isl_map.c

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/*
 * Copyright 2008-2009 Katholieke Universiteit Leuven
 * Copyright 2010      INRIA Saclay
 * Copyright 2012-2014 Ecole Normale Superieure
 * Copyright 2014      INRIA Rocquencourt
 * Copyright 2016      INRIA Paris
 * Copyright 2016      Sven Verdoolaege
 * Copyright 2018-2019 Cerebras Systems
 * Copyright 2021-2022 Cerebras Systems
 *
 * Use of this software is governed by the MIT license
 *
 * Written by Sven Verdoolaege, K.U.Leuven, Departement
 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
 * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
 * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France 
 * and Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
 * and Inria Paris - Rocquencourt, Domaine de Voluceau - Rocquencourt,
 * B.P. 105 - 78153 Le Chesnay, France
 * and Centre de Recherche Inria de Paris, 2 rue Simone Iff - Voie DQ12,
 * CS 42112, 75589 Paris Cedex 12, France
 * and Cerebras Systems, 175 S San Antonio Rd, Los Altos, CA, USA
 * and Cerebras Systems, 1237 E Arques Ave, Sunnyvale, CA, USA
 */
 
#include <string.h>
#include <isl_ctx_private.h>
#include <isl_map_private.h>
#include <isl_blk.h>
#include <isl_id_private.h>
#include <isl/constraint.h>
#include "isl_space_private.h"
#include "isl_equalities.h"
#include <isl_lp_private.h>
#include <isl_seq.h>
#include <isl/set.h>
#include <isl/map.h>
#include <isl_reordering.h>
#include "isl_sample.h"
#include <isl_sort.h>
#include "isl_tab.h"
#include <isl/vec.h>
#include <isl_mat_private.h>
#include <isl_vec_private.h>
#include <isl_dim_map.h>
#include <isl_local_space_private.h>
#include <isl_aff_private.h>
#include <isl_options_private.h>
#include <isl_morph.h>
#include <isl_val_private.h>
#include <isl_printer_private.h>
#include <isl_maybe_aff.h>
 
#include <bset_to_bmap.c>
#include <bset_from_bmap.c>
#include <set_to_map.c>
#include <set_from_map.c>
 
/* Treat "bset" as a basic map.
 * Internally, isl_basic_set is defined to isl_basic_map, so in practice,
 * this function performs a redundant cast.
 */
static __isl_keep const isl_basic_map *const_bset_to_bmap(
  __isl_keep const isl_basic_set *bset)
{
  return (const isl_basic_map *) bset;
}
 
#undef TYPE
#define TYPE  isl_basic_map
#include "has_single_reference_templ.c"
 
static unsigned pos(__isl_keep isl_space *space, enum isl_dim_type type)
{
  switch (type) {
  case isl_dim_param:  return 1;
  case isl_dim_in:  return 1 + space->nparam;
  case isl_dim_out:  return 1 + space->nparam + space->n_in;
  default:    return 0;
  }
}
 
isl_size isl_basic_map_dim(__isl_keep isl_basic_map *bmap,
        enum isl_dim_type type)
{
  if (!bmap)
    return isl_size_error;
  switch (type) {
  case isl_dim_cst:  return 1;
  case isl_dim_param:
  case isl_dim_in:
  case isl_dim_out:  return isl_space_dim(bmap->dim, type);
  case isl_dim_div:  return bmap->n_div;
  case isl_dim_all:  return isl_basic_map_total_dim(bmap);
  default:    return 0;
  }
}
 
/* Return the space of "map".
 */
__isl_keep isl_space *isl_map_peek_space(__isl_keep const isl_map *map)
{
  return map ? map->dim : NULL;
}
 
/* Return the space of "set".
 */
__isl_keep isl_space *isl_set_peek_space(__isl_keep isl_set *set)
{
  return isl_map_peek_space(set_to_map(set));
}
 
isl_size isl_map_dim(__isl_keep isl_map *map, enum isl_dim_type type)
{
  return isl_space_dim(isl_map_peek_space(map), type);
}
 
/* Return the dimensionality of the domain (tuple) of the map.
 */
isl_size isl_map_domain_tuple_dim(__isl_keep isl_map *map)
{
  return isl_map_dim(map, isl_dim_in);
}
 
/* Return the dimensionality of the range (tuple) of the map.
 */
isl_size isl_map_range_tuple_dim(__isl_keep isl_map *map)
{
  return isl_map_dim(map, isl_dim_out);
}
 
isl_size isl_set_dim(__isl_keep isl_set *set, enum isl_dim_type type)
{
  return isl_map_dim(set_to_map(set), type);
}
 
/* Return the dimensionality of the (tuple of the) set.
 */
isl_size isl_set_tuple_dim(__isl_keep isl_set *set)
{
  return isl_set_dim(set, isl_dim_set);
}
 
/* Return the position of the variables of the given type
 * within the sequence of variables of "bmap".
 */
isl_size isl_basic_map_var_offset(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type)
{
  isl_space *space;
 
  space = isl_basic_map_peek_space(bmap);
 
  switch (type) {
  case isl_dim_param:
  case isl_dim_in:
  case isl_dim_out:  return isl_space_offset(space, type);
  case isl_dim_div:  return isl_space_dim(space, isl_dim_all);
  case isl_dim_cst:
  default:
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "invalid dimension type", return isl_size_error);
  }
}
 
/* Return the position of the variables of the given type
 * within the sequence of variables of "bset".
 */
isl_size isl_basic_set_var_offset(__isl_keep isl_basic_set *bset,
  enum isl_dim_type type)
{
  return isl_basic_map_var_offset(bset_to_bmap(bset), type);
}
 
/* Return the position of the coefficients of the variables of the given type
 * within the sequence of coefficients of "bmap".
 */
unsigned isl_basic_map_offset(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type)
{
  switch (type) {
  case isl_dim_cst:  return 0;
  case isl_dim_param:
  case isl_dim_in:
  case isl_dim_out:
  case isl_dim_div:  return 1 + isl_basic_map_var_offset(bmap, type);
  default:    return 0;
  }
}
 
unsigned isl_basic_set_offset(__isl_keep isl_basic_set *bset,
          enum isl_dim_type type)
{
  return isl_basic_map_offset(bset, type);
}
 
static unsigned map_offset(__isl_keep isl_map *map, enum isl_dim_type type)
{
  return pos(map->dim, type);
}
 
isl_size isl_basic_set_dim(__isl_keep isl_basic_set *bset,
        enum isl_dim_type type)
{
  return isl_basic_map_dim(bset, type);
}
 
isl_size isl_basic_set_n_dim(__isl_keep isl_basic_set *bset)
{
  return isl_basic_set_dim(bset, isl_dim_set);
}
 
isl_size isl_basic_set_n_param(__isl_keep isl_basic_set *bset)
{
  return isl_basic_set_dim(bset, isl_dim_param);
}
 
isl_size isl_basic_set_total_dim(__isl_keep const isl_basic_set *bset)
{
  return isl_basic_map_total_dim(const_bset_to_bmap(bset));
}
 
isl_size isl_set_n_dim(__isl_keep isl_set *set)
{
  return isl_set_dim(set, isl_dim_set);
}
 
isl_size isl_set_n_param(__isl_keep isl_set *set)
{
  return isl_set_dim(set, isl_dim_param);
}
 
isl_size isl_basic_map_total_dim(__isl_keep const isl_basic_map *bmap)
{
  isl_size dim;
 
  if (!bmap)
    return isl_size_error;
  dim = isl_space_dim(bmap->dim, isl_dim_all);
  if (dim < 0)
    return isl_size_error;
  return dim + bmap->n_div;
}
 
/* Return the number of equality constraints in the description of "bmap".
 * Return isl_size_error on error.
 */
isl_size isl_basic_map_n_equality(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_size_error;
  return bmap->n_eq;
}
 
/* Return the number of equality constraints in the description of "bset".
 * Return isl_size_error on error.
 */
isl_size isl_basic_set_n_equality(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_n_equality(bset_to_bmap(bset));
}
 
/* Return the number of inequality constraints in the description of "bmap".
 * Return isl_size_error on error.
 */
isl_size isl_basic_map_n_inequality(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_size_error;
  return bmap->n_ineq;
}
 
/* Return the number of inequality constraints in the description of "bset".
 * Return isl_size_error on error.
 */
isl_size isl_basic_set_n_inequality(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_n_inequality(bset_to_bmap(bset));
}
 
/* Do "bmap1" and "bmap2" have the same parameters?
 */
static isl_bool isl_basic_map_has_equal_params(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  isl_space *space1, *space2;
 
  space1 = isl_basic_map_peek_space(bmap1);
  space2 = isl_basic_map_peek_space(bmap2);
  return isl_space_has_equal_params(space1, space2);
}
 
/* Do "map1" and "map2" have the same parameters?
 */
isl_bool isl_map_has_equal_params(__isl_keep isl_map *map1,
  __isl_keep isl_map *map2)
{
  isl_space *space1, *space2;
 
  space1 = isl_map_peek_space(map1);
  space2 = isl_map_peek_space(map2);
  return isl_space_has_equal_params(space1, space2);
}
 
/* Do "map" and "set" have the same parameters?
 */
static isl_bool isl_map_set_has_equal_params(__isl_keep isl_map *map,
  __isl_keep isl_set *set)
{
  return isl_map_has_equal_params(map, set_to_map(set));
}
 
/* Is the tuple of type "type" of "bmap" the same as the single tuple of "bset"?
 */
static isl_bool isl_basic_map_set_tuple_is_equal(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, __isl_keep isl_basic_set *bset)
{
  isl_space *bmap_space, *bset_space;
 
  bmap_space = isl_basic_map_peek_space(bmap);
  bset_space = isl_basic_set_peek_space(bset);
  return isl_space_tuple_is_equal(bmap_space, type,
          bset_space, isl_dim_set);
}
 
/* Is the tuple of type "type" of "map" the same as the single tuple of "set"?
 */
static isl_bool isl_map_set_tuple_is_equal(__isl_keep isl_map *map,
  enum isl_dim_type type, __isl_keep isl_set *set)
{
  return isl_map_tuple_is_equal(map, type, set_to_map(set), isl_dim_set);
}
 
isl_bool isl_map_compatible_domain(__isl_keep isl_map *map,
  __isl_keep isl_set *set)
{
  isl_bool m;
  if (!map || !set)
    return isl_bool_error;
  m = isl_map_has_equal_params(map, set_to_map(set));
  if (m < 0 || !m)
    return m;
  return isl_map_set_tuple_is_equal(map, isl_dim_in, set);
}
 
isl_bool isl_basic_map_compatible_domain(__isl_keep isl_basic_map *bmap,
  __isl_keep isl_basic_set *bset)
{
  isl_bool m;
  if (!bmap || !bset)
    return isl_bool_error;
  m = isl_basic_map_has_equal_params(bmap, bset_to_bmap(bset));
  if (m < 0 || !m)
    return m;
  return isl_basic_map_set_tuple_is_equal(bmap, isl_dim_in, bset);
}
 
isl_bool isl_map_compatible_range(__isl_keep isl_map *map,
  __isl_keep isl_set *set)
{
  isl_bool m;
  if (!map || !set)
    return isl_bool_error;
  m = isl_map_has_equal_params(map, set_to_map(set));
  if (m < 0 || !m)
    return m;
  return isl_map_set_tuple_is_equal(map, isl_dim_out, set);
}
 
isl_bool isl_basic_map_compatible_range(__isl_keep isl_basic_map *bmap,
  __isl_keep isl_basic_set *bset)
{
  isl_bool m;
  if (!bmap || !bset)
    return isl_bool_error;
  m = isl_basic_map_has_equal_params(bmap, bset_to_bmap(bset));
  if (m < 0 || !m)
    return m;
  return isl_basic_map_set_tuple_is_equal(bmap, isl_dim_out, bset);
}
 
isl_ctx *isl_basic_map_get_ctx(__isl_keep isl_basic_map *bmap)
{
  return bmap ? bmap->ctx : NULL;
}
 
isl_ctx *isl_basic_set_get_ctx(__isl_keep isl_basic_set *bset)
{
  return bset ? bset->ctx : NULL;
}
 
isl_ctx *isl_map_get_ctx(__isl_keep isl_map *map)
{
  return map ? map->ctx : NULL;
}
 
isl_ctx *isl_set_get_ctx(__isl_keep isl_set *set)
{
  return set ? set->ctx : NULL;
}
 
/* Return the space of "bmap".
 */
__isl_keep isl_space *isl_basic_map_peek_space(
  __isl_keep const isl_basic_map *bmap)
{
  return bmap ? bmap->dim : NULL;
}
 
/* Return the space of "bset".
 */
__isl_keep isl_space *isl_basic_set_peek_space(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_peek_space(bset_to_bmap(bset));
}
 
__isl_give isl_space *isl_basic_map_get_space(__isl_keep isl_basic_map *bmap)
{
  return isl_space_copy(isl_basic_map_peek_space(bmap));
}
 
__isl_give isl_space *isl_basic_set_get_space(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_get_space(bset_to_bmap(bset));
}
 
/* Return the space of "bmap".
 * This may be either a copy or the space itself
 * if there is only one reference to "bmap".
 * This allows the space to be modified inplace
 * if both the basic map and its space have only a single reference.
 * The caller is not allowed to modify "bmap" between this call and
 * a subsequent call to isl_basic_map_restore_space.
 * The only exception is that isl_basic_map_free can be called instead.
 */
static __isl_give isl_space *isl_basic_map_take_space(
  __isl_keep isl_basic_map *bmap)
{
  isl_space *space;
 
  if (!bmap)
    return NULL;
  if (bmap->ref != 1)
    return isl_basic_map_get_space(bmap);
  space = bmap->dim;
  bmap->dim = NULL;
  return space;
}
 
/* Set the space of "bmap" to "space", where the space of "bmap" may be missing
 * due to a preceding call to isl_basic_map_take_space.
 * However, in this case, "bmap" only has a single reference and
 * then the call to isl_basic_map_cow has no effect.
 */
static __isl_give isl_basic_map *isl_basic_map_restore_space(
  __isl_take isl_basic_map *bmap, __isl_take isl_space *space)
{
  if (!bmap || !space)
    goto error;
 
  if (bmap->dim == space) {
    isl_space_free(space);
    return bmap;
  }
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    goto error;
  isl_space_free(bmap->dim);
  bmap->dim = space;
 
  return bmap;
error:
  isl_basic_map_free(bmap);
  isl_space_free(space);
  return NULL;
}
 
/* Extract the divs in "bmap" as a matrix.
 */
__isl_give isl_mat *isl_basic_map_get_divs(__isl_keep isl_basic_map *bmap)
{
  int i;
  isl_ctx *ctx;
  isl_mat *div;
  isl_size v_div;
  unsigned cols;
 
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  if (v_div < 0)
    return NULL;
 
  ctx = isl_basic_map_get_ctx(bmap);
  cols = 1 + 1 + v_div + bmap->n_div;
  div = isl_mat_alloc(ctx, bmap->n_div, cols);
  if (!div)
    return NULL;
 
  for (i = 0; i < bmap->n_div; ++i)
    isl_seq_cpy(div->row[i], bmap->div[i], cols);
 
  return div;
}
 
/* Extract the divs in "bset" as a matrix.
 */
__isl_give isl_mat *isl_basic_set_get_divs(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_get_divs(bset);
}
 
__isl_give isl_local_space *isl_basic_map_get_local_space(
  __isl_keep isl_basic_map *bmap)
{
  isl_mat *div;
 
  if (!bmap)
    return NULL;
 
  div = isl_basic_map_get_divs(bmap);
  return isl_local_space_alloc_div(isl_space_copy(bmap->dim), div);
}
 
__isl_give isl_local_space *isl_basic_set_get_local_space(
  __isl_keep isl_basic_set *bset)
{
  return isl_basic_map_get_local_space(bset);
}
 
/* For each known div d = floor(f/m), add the constraints
 *
 *    f - m d >= 0
 *    -(f-(m-1)) + m d >= 0
 *
 * Do not finalize the result.
 */
static __isl_give isl_basic_map *add_known_div_constraints(
  __isl_take isl_basic_map *bmap)
{
  int i;
  isl_size n_div;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_div < 0)
    return isl_basic_map_free(bmap);
  if (n_div == 0)
    return bmap;
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 0, 2 * n_div);
  if (!bmap)
    return NULL;
  for (i = 0; i < n_div; ++i) {
    if (isl_int_is_zero(bmap->div[i][0]))
      continue;
    bmap = isl_basic_map_add_div_constraints(bmap, i);
  }
 
  return bmap;
}
 
__isl_give isl_basic_map *isl_basic_map_from_local_space(
  __isl_take isl_local_space *ls)
{
  int i;
  isl_size n_div;
  isl_basic_map *bmap;
 
  n_div = isl_local_space_dim(ls, isl_dim_div);
  if (n_div < 0)
    ls = isl_local_space_free(ls);
  if (!ls)
    return NULL;
 
  bmap = isl_basic_map_alloc_space(isl_local_space_get_space(ls),
          n_div, 0, 2 * n_div);
 
  for (i = 0; i < n_div; ++i)
    if (isl_basic_map_alloc_div(bmap) < 0)
      goto error;
 
  for (i = 0; i < n_div; ++i)
    isl_seq_cpy(bmap->div[i], ls->div->row[i], ls->div->n_col);
  bmap = add_known_div_constraints(bmap);
          
  isl_local_space_free(ls);
  return bmap;
error:
  isl_local_space_free(ls);
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_from_local_space(
  __isl_take isl_local_space *ls)
{
  return isl_basic_map_from_local_space(ls);
}
 
__isl_give isl_space *isl_map_get_space(__isl_keep isl_map *map)
{
  return isl_space_copy(isl_map_peek_space(map));
}
 
__isl_give isl_space *isl_set_get_space(__isl_keep isl_set *set)
{
  if (!set)
    return NULL;
  return isl_space_copy(set->dim);
}
 
/* Return the space of "map".
 * This may be either a copy or the space itself
 * if there is only one reference to "map".
 * This allows the space to be modified inplace
 * if both the map and its space have only a single reference.
 * The caller is not allowed to modify "map" between this call and
 * a subsequent call to isl_map_restore_space.
 * The only exception is that isl_map_free can be called instead.
 */
static __isl_give isl_space *isl_map_take_space(__isl_keep isl_map *map)
{
  isl_space *space;
 
  if (!map)
    return NULL;
  if (map->ref != 1)
    return isl_map_get_space(map);
  space = map->dim;
  map->dim = NULL;
  return space;
}
 
/* Set the space of "map" to "space", where the space of "map" may be missing
 * due to a preceding call to isl_map_take_space.
 * However, in this case, "map" only has a single reference and
 * then the call to isl_map_cow has no effect.
 */
static __isl_give isl_map *isl_map_restore_space(__isl_take isl_map *map,
  __isl_take isl_space *space)
{
  if (!map || !space)
    goto error;
 
  if (map->dim == space) {
    isl_space_free(space);
    return map;
  }
 
  map = isl_map_cow(map);
  if (!map)
    goto error;
  isl_space_free(map->dim);
  map->dim = space;
 
  return map;
error:
  isl_map_free(map);
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_set_tuple_name(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type, const char *s)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_set_tuple_name(space, type, s);
  bmap = isl_basic_map_restore_space(bmap, space);
  bmap = isl_basic_map_finalize(bmap);
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_set_tuple_name(
  __isl_take isl_basic_set *bset, const char *s)
{
  return isl_basic_map_set_tuple_name(bset, isl_dim_set, s);
}
 
const char *isl_basic_map_get_tuple_name(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type)
{
  return bmap ? isl_space_get_tuple_name(bmap->dim, type) : NULL;
}
 
__isl_give isl_map *isl_map_set_tuple_name(__isl_take isl_map *map,
  enum isl_dim_type type, const char *s)
{
  int i;
  isl_space *space;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_set_tuple_name(map->p[i], type, s);
    if (!map->p[i])
      goto error;
  }
 
  space = isl_map_take_space(map);
  space = isl_space_set_tuple_name(space, type, s);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
/* Replace the identifier of the tuple of type "type" by "id".
 */
__isl_give isl_basic_map *isl_basic_map_set_tuple_id(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, __isl_take isl_id *id)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_set_tuple_id(space, type, id);
  bmap = isl_basic_map_restore_space(bmap, space);
  bmap = isl_basic_map_finalize(bmap);
  return bmap;
}
 
/* Replace the identifier of the tuple by "id".
 */
__isl_give isl_basic_set *isl_basic_set_set_tuple_id(
  __isl_take isl_basic_set *bset, __isl_take isl_id *id)
{
  return isl_basic_map_set_tuple_id(bset, isl_dim_set, id);
}
 
/* Does the input or output tuple have a name?
 */
isl_bool isl_map_has_tuple_name(__isl_keep isl_map *map, enum isl_dim_type type)
{
  return map ? isl_space_has_tuple_name(map->dim, type) : isl_bool_error;
}
 
const char *isl_map_get_tuple_name(__isl_keep isl_map *map,
  enum isl_dim_type type)
{
  return map ? isl_space_get_tuple_name(map->dim, type) : NULL;
}
 
__isl_give isl_set *isl_set_set_tuple_name(__isl_take isl_set *set,
  const char *s)
{
  return set_from_map(isl_map_set_tuple_name(set_to_map(set),
            isl_dim_set, s));
}
 
__isl_give isl_map *isl_map_set_tuple_id(__isl_take isl_map *map,
  enum isl_dim_type type, __isl_take isl_id *id)
{
  isl_space *space;
 
  space = isl_map_take_space(map);
  space = isl_space_set_tuple_id(space, type, id);
  map = isl_map_restore_space(map, space);
 
  return isl_map_reset_space(map, isl_map_get_space(map));
}
 
/* Replace the identifier of the domain tuple of "map" by "id".
 */
__isl_give isl_map *isl_map_set_domain_tuple_id(__isl_take isl_map *map,
  __isl_take isl_id *id)
{
  return isl_map_set_tuple_id(map, isl_dim_in, id);
}
 
/* Replace the identifier of the range tuple of "map" by "id".
 */
__isl_give isl_map *isl_map_set_range_tuple_id(__isl_take isl_map *map,
  __isl_take isl_id *id)
{
  return isl_map_set_tuple_id(map, isl_dim_out, id);
}
 
__isl_give isl_set *isl_set_set_tuple_id(__isl_take isl_set *set,
  __isl_take isl_id *id)
{
  return isl_map_set_tuple_id(set, isl_dim_set, id);
}
 
__isl_give isl_map *isl_map_reset_tuple_id(__isl_take isl_map *map,
  enum isl_dim_type type)
{
  isl_space *space;
 
  space = isl_map_take_space(map);
  space = isl_space_reset_tuple_id(space, type);
  map = isl_map_restore_space(map, space);
 
  return isl_map_reset_space(map, isl_map_get_space(map));
}
 
__isl_give isl_set *isl_set_reset_tuple_id(__isl_take isl_set *set)
{
  return isl_map_reset_tuple_id(set, isl_dim_set);
}
 
isl_bool isl_map_has_tuple_id(__isl_keep isl_map *map, enum isl_dim_type type)
{
  return map ? isl_space_has_tuple_id(map->dim, type) : isl_bool_error;
}
 
/* Does the domain tuple of "map" have an identifier?
 */
isl_bool isl_map_has_domain_tuple_id(__isl_keep isl_map *map)
{
  return isl_map_has_tuple_id(map, isl_dim_in);
}
 
/* Does the range tuple of "map" have an identifier?
 */
isl_bool isl_map_has_range_tuple_id(__isl_keep isl_map *map)
{
  return isl_map_has_tuple_id(map, isl_dim_out);
}
 
__isl_give isl_id *isl_map_get_tuple_id(__isl_keep isl_map *map,
  enum isl_dim_type type)
{
  return map ? isl_space_get_tuple_id(map->dim, type) : NULL;
}
 
/* Return the identifier of the domain tuple of "map", assuming it has one.
 */
__isl_give isl_id *isl_map_get_domain_tuple_id(__isl_keep isl_map *map)
{
  return isl_map_get_tuple_id(map, isl_dim_in);
}
 
/* Return the identifier of the range tuple of "map", assuming it has one.
 */
__isl_give isl_id *isl_map_get_range_tuple_id(__isl_keep isl_map *map)
{
  return isl_map_get_tuple_id(map, isl_dim_out);
}
 
isl_bool isl_set_has_tuple_id(__isl_keep isl_set *set)
{
  return isl_map_has_tuple_id(set, isl_dim_set);
}
 
__isl_give isl_id *isl_set_get_tuple_id(__isl_keep isl_set *set)
{
  return isl_map_get_tuple_id(set, isl_dim_set);
}
 
/* Does the set tuple have a name?
 */
isl_bool isl_set_has_tuple_name(__isl_keep isl_set *set)
{
  if (!set)
    return isl_bool_error;
  return isl_space_has_tuple_name(set->dim, isl_dim_set);
}
 
 
const char *isl_basic_set_get_tuple_name(__isl_keep isl_basic_set *bset)
{
  return bset ? isl_space_get_tuple_name(bset->dim, isl_dim_set) : NULL;
}
 
const char *isl_set_get_tuple_name(__isl_keep isl_set *set)
{
  return set ? isl_space_get_tuple_name(set->dim, isl_dim_set) : NULL;
}
 
const char *isl_basic_map_get_dim_name(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos)
{
  return bmap ? isl_space_get_dim_name(bmap->dim, type, pos) : NULL;
}
 
const char *isl_basic_set_get_dim_name(__isl_keep isl_basic_set *bset,
  enum isl_dim_type type, unsigned pos)
{
  return bset ? isl_space_get_dim_name(bset->dim, type, pos) : NULL;
}
 
/* Does the given dimension have a name?
 */
isl_bool isl_map_has_dim_name(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos)
{
  if (!map)
    return isl_bool_error;
  return isl_space_has_dim_name(map->dim, type, pos);
}
 
const char *isl_map_get_dim_name(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos)
{
  return map ? isl_space_get_dim_name(map->dim, type, pos) : NULL;
}
 
const char *isl_set_get_dim_name(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return set ? isl_space_get_dim_name(set->dim, type, pos) : NULL;
}
 
/* Does the given dimension have a name?
 */
isl_bool isl_set_has_dim_name(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  if (!set)
    return isl_bool_error;
  return isl_space_has_dim_name(set->dim, type, pos);
}
 
__isl_give isl_basic_map *isl_basic_map_set_dim_name(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, const char *s)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_set_dim_name(space, type, pos, s);
  bmap = isl_basic_map_restore_space(bmap, space);
  return isl_basic_map_finalize(bmap);
}
 
__isl_give isl_map *isl_map_set_dim_name(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, const char *s)
{
  int i;
  isl_space *space;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_set_dim_name(map->p[i], type, pos, s);
    if (!map->p[i])
      goto error;
  }
 
  space = isl_map_take_space(map);
  space = isl_space_set_dim_name(space, type, pos, s);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_set_dim_name(
  __isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned pos, const char *s)
{
  return bset_from_bmap(isl_basic_map_set_dim_name(bset_to_bmap(bset),
              type, pos, s));
}
 
__isl_give isl_set *isl_set_set_dim_name(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, const char *s)
{
  return set_from_map(isl_map_set_dim_name(set_to_map(set),
              type, pos, s));
}
 
isl_bool isl_basic_map_has_dim_id(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos)
{
  if (!bmap)
    return isl_bool_error;
  return isl_space_has_dim_id(bmap->dim, type, pos);
}
 
__isl_give isl_id *isl_basic_set_get_dim_id(__isl_keep isl_basic_set *bset,
  enum isl_dim_type type, unsigned pos)
{
  return bset ? isl_space_get_dim_id(bset->dim, type, pos) : NULL;
}
 
isl_bool isl_map_has_dim_id(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos)
{
  return map ? isl_space_has_dim_id(map->dim, type, pos) : isl_bool_error;
}
 
__isl_give isl_id *isl_map_get_dim_id(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos)
{
  return map ? isl_space_get_dim_id(map->dim, type, pos) : NULL;
}
 
isl_bool isl_set_has_dim_id(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return isl_map_has_dim_id(set, type, pos);
}
 
__isl_give isl_id *isl_set_get_dim_id(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return isl_map_get_dim_id(set, type, pos);
}
 
__isl_give isl_map *isl_map_set_dim_id(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, __isl_take isl_id *id)
{
  isl_space *space;
 
  space = isl_map_take_space(map);
  space = isl_space_set_dim_id(space, type, pos, id);
  map = isl_map_restore_space(map, space);
 
  return isl_map_reset_space(map, isl_map_get_space(map));
}
 
__isl_give isl_set *isl_set_set_dim_id(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, __isl_take isl_id *id)
{
  return isl_map_set_dim_id(set, type, pos, id);
}
 
int isl_map_find_dim_by_id(__isl_keep isl_map *map, enum isl_dim_type type,
  __isl_keep isl_id *id)
{
  if (!map)
    return -1;
  return isl_space_find_dim_by_id(map->dim, type, id);
}
 
int isl_set_find_dim_by_id(__isl_keep isl_set *set, enum isl_dim_type type,
  __isl_keep isl_id *id)
{
  return isl_map_find_dim_by_id(set, type, id);
}
 
/* Return the position of the dimension of the given type and name
 * in "bmap".
 * Return -1 if no such dimension can be found.
 */
int isl_basic_map_find_dim_by_name(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, const char *name)
{
  if (!bmap)
    return -1;
  return isl_space_find_dim_by_name(bmap->dim, type, name);
}
 
int isl_map_find_dim_by_name(__isl_keep isl_map *map, enum isl_dim_type type,
  const char *name)
{
  if (!map)
    return -1;
  return isl_space_find_dim_by_name(map->dim, type, name);
}
 
int isl_set_find_dim_by_name(__isl_keep isl_set *set, enum isl_dim_type type,
  const char *name)
{
  return isl_map_find_dim_by_name(set, type, name);
}
 
/* Check whether equality i of bset is a pure stride constraint
 * on a single dimension, i.e., of the form
 *
 *  v = k e
 *
 * with k a constant and e an existentially quantified variable.
 */
isl_bool isl_basic_set_eq_is_stride(__isl_keep isl_basic_set *bset, int i)
{
  isl_size nparam;
  isl_size d;
  isl_size n_div;
  int pos1;
  int pos2;
 
  nparam = isl_basic_set_dim(bset, isl_dim_param);
  d = isl_basic_set_dim(bset, isl_dim_set);
  n_div = isl_basic_set_dim(bset, isl_dim_div);
  if (nparam < 0 || d < 0 || n_div < 0)
    return isl_bool_error;
 
  if (!isl_int_is_zero(bset->eq[i][0]))
    return isl_bool_false;
 
  if (isl_seq_any_non_zero(bset->eq[i] + 1, nparam))
    return isl_bool_false;
  pos1 = isl_seq_first_non_zero(bset->eq[i] + 1 + nparam, d);
  if (pos1 == -1)
    return isl_bool_false;
  if (isl_seq_any_non_zero(bset->eq[i] + 1 + nparam + pos1 + 1,
          d - pos1 - 1))
    return isl_bool_false;
 
  pos2 = isl_seq_first_non_zero(bset->eq[i] + 1 + nparam + d, n_div);
  if (pos2 == -1)
    return isl_bool_false;
  if (isl_seq_any_non_zero(bset->eq[i] + 1 + nparam + d  + pos2 + 1,
           n_div - pos2 - 1))
    return isl_bool_false;
  if (!isl_int_is_one(bset->eq[i][1 + nparam + pos1]) &&
      !isl_int_is_negone(bset->eq[i][1 + nparam + pos1]))
    return isl_bool_false;
 
  return isl_bool_true;
}
 
/* Reset the user pointer on all identifiers of parameters and tuples
 * of the space of "map".
 */
__isl_give isl_map *isl_map_reset_user(__isl_take isl_map *map)
{
  isl_space *space;
 
  space = isl_map_get_space(map);
  space = isl_space_reset_user(space);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Reset the user pointer on all identifiers of parameters and tuples
 * of the space of "set".
 */
__isl_give isl_set *isl_set_reset_user(__isl_take isl_set *set)
{
  return isl_map_reset_user(set);
}
 
isl_bool isl_basic_map_is_rational(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
  return ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL);
}
 
/* Has "map" been marked as a rational map?
 * In particular, have all basic maps in "map" been marked this way?
 * An empty map is not considered to be rational.
 * Maps where only some of the basic maps are marked rational
 * are not allowed.
 */
isl_bool isl_map_is_rational(__isl_keep isl_map *map)
{
  int i;
  isl_bool rational;
 
  if (!map)
    return isl_bool_error;
  if (map->n == 0)
    return isl_bool_false;
  rational = isl_basic_map_is_rational(map->p[0]);
  if (rational < 0)
    return rational;
  for (i = 1; i < map->n; ++i) {
    isl_bool rational_i;
 
    rational_i = isl_basic_map_is_rational(map->p[i]);
    if (rational_i < 0)
      return rational_i;
    if (rational != rational_i)
      isl_die(isl_map_get_ctx(map), isl_error_unsupported,
        "mixed rational and integer basic maps "
        "not supported", return isl_bool_error);
  }
 
  return rational;
}
 
/* Has "set" been marked as a rational set?
 * In particular, have all basic set in "set" been marked this way?
 * An empty set is not considered to be rational.
 * Sets where only some of the basic sets are marked rational
 * are not allowed.
 */
isl_bool isl_set_is_rational(__isl_keep isl_set *set)
{
  return isl_map_is_rational(set);
}
 
int isl_basic_set_is_rational(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_is_rational(bset);
}
 
/* Does "bmap" contain any rational points?
 *
 * If "bmap" has an equality for each dimension, equating the dimension
 * to an integer constant, then it has no rational points, even if it
 * is marked as rational.
 */
isl_bool isl_basic_map_has_rational(__isl_keep isl_basic_map *bmap)
{
  isl_bool has_rational = isl_bool_true;
  isl_size total;
 
  if (!bmap)
    return isl_bool_error;
  if (isl_basic_map_plain_is_empty(bmap))
    return isl_bool_false;
  if (!isl_basic_map_is_rational(bmap))
    return isl_bool_false;
  bmap = isl_basic_map_copy(bmap);
  bmap = isl_basic_map_implicit_equalities(bmap);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_bool_error;
  if (bmap->n_eq == total) {
    int i, j;
    for (i = 0; i < bmap->n_eq; ++i) {
      j = isl_seq_first_non_zero(bmap->eq[i] + 1, total);
      if (j < 0)
        break;
      if (!isl_int_is_one(bmap->eq[i][1 + j]) &&
          !isl_int_is_negone(bmap->eq[i][1 + j]))
        break;
      if (isl_seq_any_non_zero(bmap->eq[i] + 1 + j + 1,
                total - j - 1))
        break;
    }
    if (i == bmap->n_eq)
      has_rational = isl_bool_false;
  }
  isl_basic_map_free(bmap);
 
  return has_rational;
}
 
/* Does "map" contain any rational points?
 */
isl_bool isl_map_has_rational(__isl_keep isl_map *map)
{
  int i;
  isl_bool has_rational;
 
  if (!map)
    return isl_bool_error;
  for (i = 0; i < map->n; ++i) {
    has_rational = isl_basic_map_has_rational(map->p[i]);
    if (has_rational < 0 || has_rational)
      return has_rational;
  }
  return isl_bool_false;
}
 
/* Does "set" contain any rational points?
 */
isl_bool isl_set_has_rational(__isl_keep isl_set *set)
{
  return isl_map_has_rational(set);
}
 
/* Is this basic set a parameter domain?
 */
isl_bool isl_basic_set_is_params(__isl_keep isl_basic_set *bset)
{
  if (!bset)
    return isl_bool_error;
  return isl_space_is_params(bset->dim);
}
 
/* Is this set a parameter domain?
 */
isl_bool isl_set_is_params(__isl_keep isl_set *set)
{
  if (!set)
    return isl_bool_error;
  return isl_space_is_params(set->dim);
}
 
/* Is this map actually a parameter domain?
 * Users should never call this function.  Outside of isl,
 * a map can never be a parameter domain.
 */
isl_bool isl_map_is_params(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
  return isl_space_is_params(map->dim);
}
 
static __isl_give isl_basic_map *basic_map_init(isl_ctx *ctx,
  __isl_take isl_basic_map *bmap, unsigned extra,
  unsigned n_eq, unsigned n_ineq)
{
  int i;
  isl_space *space = isl_basic_map_peek_space(bmap);
  isl_size n_var = isl_space_dim(space, isl_dim_all);
  size_t row_size = 1 + n_var + extra;
 
  bmap->ctx = ctx;
  isl_ctx_ref(ctx);
 
  if (n_var < 0)
    return isl_basic_map_free(bmap);
 
  bmap->block = isl_blk_alloc(ctx, (n_ineq + n_eq) * row_size);
  if (isl_blk_is_error(bmap->block))
    goto error;
 
  bmap->ineq = isl_alloc_array(ctx, isl_int *, n_ineq + n_eq);
  if ((n_ineq + n_eq) && !bmap->ineq)
    goto error;
 
  if (extra == 0) {
    bmap->block2 = isl_blk_empty();
    bmap->div = NULL;
  } else {
    bmap->block2 = isl_blk_alloc(ctx, extra * (1 + row_size));
    if (isl_blk_is_error(bmap->block2))
      goto error;
 
    bmap->div = isl_alloc_array(ctx, isl_int *, extra);
    if (!bmap->div)
      goto error;
  }
 
  for (i = 0; i < n_ineq + n_eq; ++i)
    bmap->ineq[i] = bmap->block.data + i * row_size;
 
  for (i = 0; i < extra; ++i)
    bmap->div[i] = bmap->block2.data + i * (1 + row_size);
 
  bmap->ref = 1;
  bmap->flags = 0;
  bmap->c_size = n_eq + n_ineq;
  bmap->eq = bmap->ineq + n_ineq;
  bmap->extra = extra;
  bmap->n_eq = 0;
  bmap->n_ineq = 0;
  bmap->n_div = 0;
  bmap->sample = NULL;
 
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_alloc(isl_ctx *ctx,
    unsigned nparam, unsigned dim, unsigned extra,
    unsigned n_eq, unsigned n_ineq)
{
  struct isl_basic_map *bmap;
  isl_space *space;
 
  space = isl_space_set_alloc(ctx, nparam, dim);
  if (!space)
    return NULL;
 
  bmap = isl_basic_map_alloc_space(space, extra, n_eq, n_ineq);
  return bset_from_bmap(bmap);
}
 
__isl_give isl_basic_set *isl_basic_set_alloc_space(__isl_take isl_space *space,
    unsigned extra, unsigned n_eq, unsigned n_ineq)
{
  struct isl_basic_map *bmap;
  if (!space)
    return NULL;
  isl_assert(space->ctx, space->n_in == 0, goto error);
  bmap = isl_basic_map_alloc_space(space, extra, n_eq, n_ineq);
  return bset_from_bmap(bmap);
error:
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_alloc_space(__isl_take isl_space *space,
    unsigned extra, unsigned n_eq, unsigned n_ineq)
{
  struct isl_basic_map *bmap;
 
  if (!space)
    return NULL;
  bmap = isl_calloc_type(space->ctx, struct isl_basic_map);
  if (!bmap)
    goto error;
  bmap->dim = space;
 
  return basic_map_init(space->ctx, bmap, extra, n_eq, n_ineq);
error:
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_alloc(isl_ctx *ctx,
    unsigned nparam, unsigned in, unsigned out, unsigned extra,
    unsigned n_eq, unsigned n_ineq)
{
  struct isl_basic_map *bmap;
  isl_space *space;
 
  space = isl_space_alloc(ctx, nparam, in, out);
  if (!space)
    return NULL;
 
  bmap = isl_basic_map_alloc_space(space, extra, n_eq, n_ineq);
  return bmap;
}
 
static __isl_give isl_basic_map *dup_constraints(__isl_take isl_basic_map *dst,
  __isl_keep isl_basic_map *src)
{
  int i;
  isl_size total = isl_basic_map_dim(src, isl_dim_all);
 
  if (!dst || total < 0)
    return isl_basic_map_free(dst);
 
  for (i = 0; i < src->n_eq; ++i) {
    int j = isl_basic_map_alloc_equality(dst);
    if (j < 0)
      return isl_basic_map_free(dst);
    isl_seq_cpy(dst->eq[j], src->eq[i], 1+total);
  }
 
  for (i = 0; i < src->n_ineq; ++i) {
    int j = isl_basic_map_alloc_inequality(dst);
    if (j < 0)
      return isl_basic_map_free(dst);
    isl_seq_cpy(dst->ineq[j], src->ineq[i], 1+total);
  }
 
  for (i = 0; i < src->n_div; ++i) {
    int j = isl_basic_map_alloc_div(dst);
    if (j < 0)
      return isl_basic_map_free(dst);
    isl_seq_cpy(dst->div[j], src->div[i], 1+1+total);
  }
  ISL_F_SET(dst, ISL_BASIC_SET_FINAL);
  return dst;
}
 
__isl_give isl_basic_map *isl_basic_map_dup(__isl_keep isl_basic_map *bmap)
{
  struct isl_basic_map *dup;
 
  if (!bmap)
    return NULL;
  dup = isl_basic_map_alloc_space(isl_space_copy(bmap->dim),
      bmap->n_div, bmap->n_eq, bmap->n_ineq);
  dup = dup_constraints(dup, bmap);
  if (!dup)
    return NULL;
  dup->flags = bmap->flags;
  dup->sample = isl_vec_copy(bmap->sample);
  return dup;
}
 
__isl_give isl_basic_set *isl_basic_set_dup(__isl_keep isl_basic_set *bset)
{
  struct isl_basic_map *dup;
 
  dup = isl_basic_map_dup(bset_to_bmap(bset));
  return bset_from_bmap(dup);
}
 
__isl_give isl_basic_set *isl_basic_set_copy(__isl_keep isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_copy(bset_to_bmap(bset)));
}
 
__isl_give isl_set *isl_set_copy(__isl_keep isl_set *set)
{
  if (!set)
    return NULL;
 
  set->ref++;
  return set;
}
 
__isl_give isl_basic_map *isl_basic_map_copy(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return NULL;
 
  if (ISL_F_ISSET(bmap, ISL_BASIC_SET_FINAL)) {
    bmap->ref++;
    return bmap;
  }
  bmap = isl_basic_map_dup(bmap);
  if (bmap)
    ISL_F_SET(bmap, ISL_BASIC_SET_FINAL);
  return bmap;
}
 
__isl_give isl_map *isl_map_copy(__isl_keep isl_map *map)
{
  if (!map)
    return NULL;
 
  map->ref++;
  return map;
}
 
__isl_null isl_basic_map *isl_basic_map_free(__isl_take isl_basic_map *bmap)
{
  if (!bmap)
    return NULL;
 
  if (--bmap->ref > 0)
    return NULL;
 
  isl_ctx_deref(bmap->ctx);
  free(bmap->div);
  isl_blk_free(bmap->ctx, bmap->block2);
  free(bmap->ineq);
  isl_blk_free(bmap->ctx, bmap->block);
  isl_vec_free(bmap->sample);
  isl_space_free(bmap->dim);
  free(bmap);
 
  return NULL;
}
 
__isl_null isl_basic_set *isl_basic_set_free(__isl_take isl_basic_set *bset)
{
  return isl_basic_map_free(bset_to_bmap(bset));
}
 
static int room_for_con(__isl_keep isl_basic_map *bmap, unsigned n)
{
  return bmap->n_eq + bmap->n_ineq + n <= bmap->c_size;
}
 
/* Check that "bset" does not involve any parameters.
 */
isl_stat isl_basic_set_check_no_params(__isl_keep isl_basic_set *bset)
{
  isl_size nparam;
 
  nparam = isl_basic_set_dim(bset, isl_dim_param);
  if (nparam < 0)
    return isl_stat_error;
  if (nparam != 0)
    isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
      "basic set should not have any parameters",
      return isl_stat_error);
  return isl_stat_ok;
}
 
/* Check that "bset" does not involve any local variables.
 */
isl_stat isl_basic_set_check_no_locals(__isl_keep isl_basic_set *bset)
{
  isl_size n_div;
 
  n_div = isl_basic_set_dim(bset, isl_dim_div);
  if (n_div < 0)
    return isl_stat_error;
  if (n_div != 0)
    isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
      "basic set should not have any local variables",
      return isl_stat_error);
  return isl_stat_ok;
}
 
#undef TYPE
#define TYPE isl_map
 
#include "isl_check_named_params_templ.c"
 
#undef TYPE
#define TYPE isl_basic_map
 
static
#include "isl_check_named_params_templ.c"
 
/* Check that "bmap1" and "bmap2" have the same parameters,
 * reporting an error if they do not.
 */
static isl_stat isl_basic_map_check_equal_params(
  __isl_keep isl_basic_map *bmap1, __isl_keep isl_basic_map *bmap2)
{
  isl_bool match;
 
  match = isl_basic_map_has_equal_params(bmap1, bmap2);
  if (match < 0)
    return isl_stat_error;
  if (!match)
    isl_die(isl_basic_map_get_ctx(bmap1), isl_error_invalid,
      "parameters don't match", return isl_stat_error);
  return isl_stat_ok;
}
 
#undef TYPE
#define TYPE  isl_map
 
#include "isl_align_params_bin_templ.c"
 
#undef SUFFIX
#define SUFFIX  set
#undef ARG1
#define ARG1  isl_map
#undef ARG2
#define ARG2  isl_set
 
#include "isl_align_params_templ.c"
 
isl_bool isl_map_align_params_map_map_and_test(__isl_keep isl_map *map1,
  __isl_keep isl_map *map2,
  isl_bool (*fn)(__isl_keep isl_map *map1, __isl_keep isl_map *map2))
{
  isl_bool r;
 
  if (!map1 || !map2)
    return isl_bool_error;
  if (isl_map_has_equal_params(map1, map2))
    return fn(map1, map2);
  if (isl_map_check_named_params(map1) < 0)
    return isl_bool_error;
  if (isl_map_check_named_params(map2) < 0)
    return isl_bool_error;
  map1 = isl_map_copy(map1);
  map2 = isl_map_copy(map2);
  map1 = isl_map_align_params(map1, isl_map_get_space(map2));
  map2 = isl_map_align_params(map2, isl_map_get_space(map1));
  r = fn(map1, map2);
  isl_map_free(map1);
  isl_map_free(map2);
  return r;
}
 
int isl_basic_map_alloc_equality(__isl_keep isl_basic_map *bmap)
{
  isl_size total;
  struct isl_ctx *ctx;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return -1;
  ctx = bmap->ctx;
  isl_assert(ctx, room_for_con(bmap, 1), return -1);
  isl_assert(ctx, (bmap->eq - bmap->ineq) + bmap->n_eq <= bmap->c_size,
      return -1);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_REDUNDANT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_IMPLICIT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_ALL_EQUALITIES);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED_DIVS);
  if ((bmap->eq - bmap->ineq) + bmap->n_eq == bmap->c_size) {
    isl_int *t;
    int j = isl_basic_map_alloc_inequality(bmap);
    if (j < 0)
      return -1;
    t = bmap->ineq[j];
    bmap->ineq[j] = bmap->ineq[bmap->n_ineq - 1];
    bmap->ineq[bmap->n_ineq - 1] = bmap->eq[-1];
    bmap->eq[-1] = t;
    bmap->n_eq++;
    bmap->n_ineq--;
    bmap->eq--;
    return 0;
  }
  isl_seq_clr(bmap->eq[bmap->n_eq] + 1 + total,
          bmap->extra - bmap->n_div);
  return bmap->n_eq++;
}
 
int isl_basic_set_alloc_equality(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_alloc_equality(bset_to_bmap(bset));
}
 
__isl_give isl_basic_map *isl_basic_map_free_equality(
  __isl_take isl_basic_map *bmap, unsigned n)
{
  if (!bmap)
    return NULL;
  if (n > bmap->n_eq)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "invalid number of equalities",
      isl_basic_map_free(bmap));
  bmap->n_eq -= n;
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_free_equality(
  __isl_take isl_basic_set *bset, unsigned n)
{
  return bset_from_bmap(isl_basic_map_free_equality(bset_to_bmap(bset),
                  n));
}
 
/* Drop the equality constraint at position "pos",
 * preserving the order of the other equality constraints.
 */
int isl_basic_map_drop_equality(__isl_keep isl_basic_map *bmap, unsigned pos)
{
  isl_int *t;
  int r;
 
  if (!bmap)
    return -1;
  isl_assert(bmap->ctx, pos < bmap->n_eq, return -1);
 
  t = bmap->eq[pos];
  bmap->n_eq--;
  for (r = pos; r < bmap->n_eq; ++r)
    bmap->eq[r] = bmap->eq[r + 1];
  bmap->eq[bmap->n_eq] = t;
 
  return 0;
}
 
/* Turn inequality "pos" of "bmap" into an equality.
 *
 * In particular, we move the inequality in front of the equalities
 * and move the last inequality in the position of the moved inequality.
 * Note that isl_tab_make_equalities_explicit depends on this particular
 * change in the ordering of the constraints.
 */
void isl_basic_map_inequality_to_equality(
    __isl_keep isl_basic_map *bmap, unsigned pos)
{
  isl_int *t;
 
  t = bmap->ineq[pos];
  bmap->ineq[pos] = bmap->ineq[bmap->n_ineq - 1];
  bmap->ineq[bmap->n_ineq - 1] = bmap->eq[-1];
  bmap->eq[-1] = t;
  bmap->n_eq++;
  bmap->n_ineq--;
  bmap->eq--;
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_REDUNDANT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED_DIVS);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_ALL_EQUALITIES);
}
 
static int room_for_ineq(__isl_keep isl_basic_map *bmap, unsigned n)
{
  return bmap->n_ineq + n <= bmap->eq - bmap->ineq;
}
 
int isl_basic_map_alloc_inequality(__isl_keep isl_basic_map *bmap)
{
  isl_size total;
  struct isl_ctx *ctx;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return -1;
  ctx = bmap->ctx;
  isl_assert(ctx, room_for_ineq(bmap, 1), return -1);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_IMPLICIT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_REDUNDANT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_ALL_EQUALITIES);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_REDUCED_COEFFICIENTS);
  isl_seq_clr(bmap->ineq[bmap->n_ineq] + 1 + total,
          bmap->extra - bmap->n_div);
  return bmap->n_ineq++;
}
 
int isl_basic_set_alloc_inequality(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_alloc_inequality(bset_to_bmap(bset));
}
 
__isl_give isl_basic_map *isl_basic_map_free_inequality(
  __isl_take isl_basic_map *bmap, unsigned n)
{
  if (!bmap)
    return NULL;
  if (n > bmap->n_ineq)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "invalid number of inequalities",
      return isl_basic_map_free(bmap));
  bmap->n_ineq -= n;
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_free_inequality(
  __isl_take isl_basic_set *bset, unsigned n)
{
  return bset_from_bmap(isl_basic_map_free_inequality(bset_to_bmap(bset),
                  n));
}
 
int isl_basic_map_drop_inequality(__isl_keep isl_basic_map *bmap, unsigned pos)
{
  isl_int *t;
  if (!bmap)
    return -1;
  isl_assert(bmap->ctx, pos < bmap->n_ineq, return -1);
 
  if (pos != bmap->n_ineq - 1) {
    t = bmap->ineq[pos];
    bmap->ineq[pos] = bmap->ineq[bmap->n_ineq - 1];
    bmap->ineq[bmap->n_ineq - 1] = t;
    ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  }
  bmap->n_ineq--;
  return 0;
}
 
int isl_basic_set_drop_inequality(__isl_keep isl_basic_set *bset, unsigned pos)
{
  return isl_basic_map_drop_inequality(bset_to_bmap(bset), pos);
}
 
__isl_give isl_basic_map *isl_basic_map_add_eq(__isl_take isl_basic_map *bmap,
  isl_int *eq)
{
  isl_bool empty;
  isl_size total;
  int k;
 
  empty = isl_basic_map_plain_is_empty(bmap);
  if (empty < 0)
    return isl_basic_map_free(bmap);
  if (empty)
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 1, 0);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  k = isl_basic_map_alloc_equality(bmap);
  if (k < 0)
    goto error;
  isl_seq_cpy(bmap->eq[k], eq, 1 + total);
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_add_eq(__isl_take isl_basic_set *bset,
  isl_int *eq)
{
  return bset_from_bmap(isl_basic_map_add_eq(bset_to_bmap(bset), eq));
}
 
__isl_give isl_basic_map *isl_basic_map_add_ineq(__isl_take isl_basic_map *bmap,
  isl_int *ineq)
{
  isl_size total;
  int k;
 
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 0, 1);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  k = isl_basic_map_alloc_inequality(bmap);
  if (k < 0)
    goto error;
  isl_seq_cpy(bmap->ineq[k], ineq, 1 + total);
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_add_ineq(__isl_take isl_basic_set *bset,
  isl_int *ineq)
{
  return bset_from_bmap(isl_basic_map_add_ineq(bset_to_bmap(bset), ineq));
}
 
int isl_basic_map_alloc_div(__isl_keep isl_basic_map *bmap)
{
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return -1;
  isl_assert(bmap->ctx, bmap->n_div < bmap->extra, return -1);
  isl_seq_clr(bmap->div[bmap->n_div] + 1 + 1 + total,
          bmap->extra - bmap->n_div);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED_DIVS);
  return bmap->n_div++;
}
 
int isl_basic_set_alloc_div(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_alloc_div(bset_to_bmap(bset));
}
 
#undef TYPE
#define TYPE  isl_basic_map
#include "check_type_range_templ.c"
 
/* Check that there are "n" dimensions of type "type" starting at "first"
 * in "bset".
 */
isl_stat isl_basic_set_check_range(__isl_keep isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_basic_map_check_range(bset_to_bmap(bset),
          type, first, n);
}
 
/* Insert an extra integer division, prescribed by "div", to "bmap"
 * at (integer division) position "pos".
 *
 * The integer division is first added at the end and then moved
 * into the right position.
 */
__isl_give isl_basic_map *isl_basic_map_insert_div(
  __isl_take isl_basic_map *bmap, int pos, __isl_keep isl_vec *div)
{
  int i, k;
  isl_size total;
 
  bmap = isl_basic_map_cow(bmap);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0 || !div)
    return isl_basic_map_free(bmap);
 
  if (div->size != 1 + 1 + total)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "unexpected size", return isl_basic_map_free(bmap));
  if (isl_basic_map_check_range(bmap, isl_dim_div, pos, 0) < 0)
    return isl_basic_map_free(bmap);
 
  bmap = isl_basic_map_extend(bmap, 1, 0, 2);
  k = isl_basic_map_alloc_div(bmap);
  if (k < 0)
    return isl_basic_map_free(bmap);
  isl_seq_cpy(bmap->div[k], div->el, div->size);
  isl_int_set_si(bmap->div[k][div->size], 0);
 
  for (i = k; i > pos; --i)
    bmap = isl_basic_map_swap_div(bmap, i, i - 1);
 
  return bmap;
}
 
/* Insert an extra integer division, prescribed by "div", to "bset"
 * at (integer division) position "pos".
 */
__isl_give isl_basic_set *isl_basic_set_insert_div(
  __isl_take isl_basic_set *bset, int pos, __isl_keep isl_vec *div)
{
  isl_basic_map *bmap = bset_to_bmap(bset);
  bmap = isl_basic_map_insert_div(bmap, pos, div);
  return bset_from_bmap(bmap);
}
 
isl_stat isl_basic_map_free_div(__isl_keep isl_basic_map *bmap, unsigned n)
{
  if (!bmap)
    return isl_stat_error;
  isl_assert(bmap->ctx, n <= bmap->n_div, return isl_stat_error);
  bmap->n_div -= n;
  return isl_stat_ok;
}
 
static __isl_give isl_basic_map *add_constraints(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2,
  unsigned i_pos, unsigned o_pos)
{
  isl_size total, n_param, n_in, n_out, n_div;
  unsigned o_in, o_out;
  isl_ctx *ctx;
  isl_space *space;
  struct isl_dim_map *dim_map;
 
  space = isl_basic_map_peek_space(bmap2);
  if (!bmap1 || !space)
    goto error;
 
  total = isl_basic_map_dim(bmap1, isl_dim_all);
  n_param = isl_basic_map_dim(bmap2, isl_dim_param);
  n_in = isl_basic_map_dim(bmap2, isl_dim_in);
  o_in = isl_basic_map_offset(bmap1, isl_dim_in) - 1 + i_pos;
  n_out = isl_basic_map_dim(bmap2, isl_dim_out);
  o_out = isl_basic_map_offset(bmap1, isl_dim_out) - 1 + o_pos;
  n_div = isl_basic_map_dim(bmap2, isl_dim_div);
  if (total < 0 || n_param < 0 || n_in < 0 || n_out < 0 || n_div < 0)
    goto error;
  ctx = isl_basic_map_get_ctx(bmap1);
  dim_map = isl_dim_map_alloc(ctx, total + n_div);
  isl_dim_map_dim_range(dim_map, space, isl_dim_param, 0, n_param, 0);
  isl_dim_map_dim_range(dim_map, space, isl_dim_in, 0, n_in, o_in);
  isl_dim_map_dim_range(dim_map, space, isl_dim_out, 0, n_out, o_out);
  isl_dim_map_div(dim_map, bmap2, total);
 
  return isl_basic_map_add_constraints_dim_map(bmap1, bmap2, dim_map);
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_extend(__isl_take isl_basic_map *base,
  unsigned extra, unsigned n_eq, unsigned n_ineq)
{
  isl_space *space;
  struct isl_basic_map *ext;
  unsigned flags;
  int dims_ok;
 
  if (!base)
    goto error;
 
  dims_ok = base->extra >= base->n_div + extra;
 
  if (dims_ok && room_for_con(base, n_eq + n_ineq) &&
           room_for_ineq(base, n_ineq))
    return base;
 
  extra += base->extra;
  n_eq += base->n_eq;
  n_ineq += base->n_ineq;
 
  space = isl_basic_map_get_space(base);
  ext = isl_basic_map_alloc_space(space, extra, n_eq, n_ineq);
  if (!ext)
    goto error;
 
  if (dims_ok)
    ext->sample = isl_vec_copy(base->sample);
  flags = base->flags;
  ext = add_constraints(ext, base, 0, 0);
  if (ext) {
    ext->flags = flags;
    ISL_F_CLR(ext, ISL_BASIC_SET_FINAL);
  }
 
  return ext;
 
error:
  isl_basic_map_free(base);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_extend(__isl_take isl_basic_set *base,
  unsigned extra, unsigned n_eq, unsigned n_ineq)
{
  return bset_from_bmap(isl_basic_map_extend(bset_to_bmap(base),
                extra, n_eq, n_ineq));
}
 
__isl_give isl_basic_map *isl_basic_map_extend_constraints(
  __isl_take isl_basic_map *base, unsigned n_eq, unsigned n_ineq)
{
  return isl_basic_map_extend(base, 0, n_eq, n_ineq);
}
 
__isl_give isl_basic_set *isl_basic_set_extend_constraints(
  __isl_take isl_basic_set *base, unsigned n_eq, unsigned n_ineq)
{
  isl_basic_map *bmap = bset_to_bmap(base);
  bmap = isl_basic_map_extend_constraints(bmap, n_eq, n_ineq);
  return bset_from_bmap(bmap);
}
 
__isl_give isl_basic_set *isl_basic_set_cow(__isl_take isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_cow(bset_to_bmap(bset)));
}
 
__isl_give isl_basic_map *isl_basic_map_cow(__isl_take isl_basic_map *bmap)
{
  if (!bmap)
    return NULL;
 
  if (bmap->ref > 1) {
    bmap->ref--;
    bmap = isl_basic_map_dup(bmap);
  }
  if (bmap)
    ISL_F_CLR(bmap, ISL_BASIC_SET_FINAL);
  return bmap;
}
 
/* Clear all cached information in "map", either because it is about
 * to be modified or because it is being freed.
 * Always return the same pointer that is passed in.
 * This is needed for the use in isl_map_free.
 */
static __isl_give isl_map *clear_caches(__isl_take isl_map *map)
{
  isl_basic_map_free(map->cached_simple_hull[0]);
  isl_basic_map_free(map->cached_simple_hull[1]);
  map->cached_simple_hull[0] = NULL;
  map->cached_simple_hull[1] = NULL;
  return map;
}
 
__isl_give isl_set *isl_set_cow(__isl_take isl_set *set)
{
  return isl_map_cow(set);
}
 
/* Return an isl_map that is equal to "map" and that has only
 * a single reference.
 *
 * If the original input already has only one reference, then
 * simply return it, but clear all cached information, since
 * it may be rendered invalid by the operations that will be
 * performed on the result.
 *
 * Otherwise, create a duplicate (without any cached information).
 */
__isl_give isl_map *isl_map_cow(__isl_take isl_map *map)
{
  if (!map)
    return NULL;
 
  if (map->ref == 1)
    return clear_caches(map);
  map->ref--;
  return isl_map_dup(map);
}
 
static void swap_vars(struct isl_blk blk, isl_int *a,
      unsigned a_len, unsigned b_len)
{
  isl_seq_cpy(blk.data, a+a_len, b_len);
  isl_seq_cpy(blk.data+b_len, a, a_len);
  isl_seq_cpy(a, blk.data, b_len+a_len);
}
 
static __isl_give isl_basic_map *isl_basic_map_swap_vars(
  __isl_take isl_basic_map *bmap, unsigned pos, unsigned n1, unsigned n2)
{
  int i;
  struct isl_blk blk;
 
  if (isl_basic_map_check_range(bmap, isl_dim_all, pos - 1, n1 + n2) < 0)
    goto error;
 
  if (n1 == 0 || n2 == 0)
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
 
  blk = isl_blk_alloc(bmap->ctx, n1 + n2);
  if (isl_blk_is_error(blk))
    goto error;
 
  for (i = 0; i < bmap->n_eq; ++i)
    swap_vars(blk,
        bmap->eq[i] + pos, n1, n2);
 
  for (i = 0; i < bmap->n_ineq; ++i)
    swap_vars(blk,
        bmap->ineq[i] + pos, n1, n2);
 
  for (i = 0; i < bmap->n_div; ++i)
    swap_vars(blk,
        bmap->div[i]+1 + pos, n1, n2);
 
  isl_blk_free(bmap->ctx, blk);
 
  ISL_F_CLR(bmap, ISL_BASIC_SET_SORTED);
  bmap = isl_basic_map_gauss(bmap, NULL);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* The given basic map has turned out to be empty.
 * Explicitly mark it as such and change the representation
 * to a canonical representation of the empty basic map.
 * Since the basic map has conflicting constraints,
 * it must have at least one constraint, except perhaps
 * if it was already explicitly marked as being empty.
 * Do nothing in the latter case, i.e., if it has been marked empty and
 * has no constraints.
 */
__isl_give isl_basic_map *isl_basic_map_set_to_empty(
  __isl_take isl_basic_map *bmap)
{
  int i = 0;
  isl_bool empty;
  isl_size n;
  isl_size total;
 
  n = isl_basic_map_n_constraint(bmap);
  empty = isl_basic_map_plain_is_empty(bmap);
  if (n < 0 || empty < 0)
    return isl_basic_map_free(bmap);
  if (n == 0 && empty)
    return bmap;
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  if (isl_basic_map_free_div(bmap, bmap->n_div) < 0)
    return isl_basic_map_free(bmap);
  bmap = isl_basic_map_free_inequality(bmap, bmap->n_ineq);
  if (!bmap)
    return NULL;
  if (bmap->n_eq > 0) {
    bmap = isl_basic_map_free_equality(bmap, bmap->n_eq - 1);
    if (!bmap)
      return NULL;
  } else {
    i = isl_basic_map_alloc_equality(bmap);
    if (i < 0)
      goto error;
  }
  isl_int_set_si(bmap->eq[i][0], 1);
  isl_seq_clr(bmap->eq[i]+1, total);
  ISL_F_SET(bmap, ISL_BASIC_MAP_EMPTY);
  isl_vec_free(bmap->sample);
  bmap->sample = NULL;
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_set_to_empty(
  __isl_take isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_set_to_empty(bset_to_bmap(bset)));
}
 
__isl_give isl_basic_map *isl_basic_map_set_rational(
  __isl_take isl_basic_map *bmap)
{
  if (!bmap)
    return NULL;
 
  if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
 
  ISL_F_SET(bmap, ISL_BASIC_MAP_RATIONAL);
 
  return isl_basic_map_finalize(bmap);
}
 
__isl_give isl_basic_set *isl_basic_set_set_rational(
  __isl_take isl_basic_set *bset)
{
  return isl_basic_map_set_rational(bset);
}
 
__isl_give isl_basic_set *isl_basic_set_set_integral(
  __isl_take isl_basic_set *bset)
{
  if (!bset)
    return NULL;
 
  if (!ISL_F_ISSET(bset, ISL_BASIC_MAP_RATIONAL))
    return bset;
 
  bset = isl_basic_set_cow(bset);
  if (!bset)
    return NULL;
 
  ISL_F_CLR(bset, ISL_BASIC_MAP_RATIONAL);
 
  return isl_basic_set_finalize(bset);
}
 
__isl_give isl_map *isl_map_set_rational(__isl_take isl_map *map)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_set_rational(map->p[i]);
    if (!map->p[i])
      goto error;
  }
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_set_rational(__isl_take isl_set *set)
{
  return isl_map_set_rational(set);
}
 
/* Given a constraint "c" that expresses a bound
 * on the variable at position "pos" in terms of the first "len" variables
 * (other than the variable itself if pos < len), extract this bound
 * as a function of those first "len" variables.
 *
 * That is, the constraint is of one of the following forms
 *
 *  -e(...) + m x >= 0
 *  e(...) - m x >= 0
 *  -e(...) + m x = 0
 *  e(...) - m x = 0
 *
 * Return (e(...)) / m, with the denominator m in the first position.
 */
static __isl_give isl_vec *extract_bound_from_constraint(isl_ctx *ctx,
  isl_int *c, int len, int pos)
{
  isl_vec *v;
 
  v = isl_vec_alloc(ctx, 1 + 1 + len);
  if (!v)
    return NULL;
  if (isl_int_is_pos(c[1 + pos])) {
    isl_int_set(v->el[0], c[1 + pos]);
    isl_seq_neg(v->el + 1, c, 1 + len);
  } else {
    isl_int_neg(v->el[0], c[1 + pos]);
    isl_seq_cpy(v->el + 1, c, 1 + len);
  }
  if (pos < len)
    isl_int_set_si(v->el[1 + 1 + pos], 0);
 
  return v;
}
 
/* Return the position of the last non-zero coefficient of
 * inequality constraint "ineq" of "bmap" or length "len",
 * given that the coefficient at position "first" is non-zero,
 * or that it is known that there is at least one coefficient
 * after "first" that is non-zero.
 */
static int extend_last_non_zero(__isl_keep isl_basic_map *bmap, int ineq,
  int first, unsigned len)
{
  int last;
 
  last = isl_seq_last_non_zero(bmap->ineq[ineq] + 1 + first + 1,
          len - (first + 1));
  if (last < 0)
    return first;
  else
    return first + 1 + last;
}
 
/* Do the inequality constraints "i" and "j" of "bmap"
 * form a pair of opposite constraints, in the (first) "len" coefficients?
 */
static int is_constraint_pair(__isl_keep isl_basic_map *bmap, int i, int j,
  unsigned len)
{
  return isl_seq_is_neg(bmap->ineq[i] + 1, bmap->ineq[j] + 1, len);
}
 
/* Given that inequality constraints "i" and "j" of "bmap"
 * form a pair of opposite constraints
 *
 *  f(x) + c1 >= 0
 *  -f(x) + c2 >= 0
 *
 * or
 *
 *  -c1 <= f(x) <= c2
 *
 * do they allow for at most "bound" values in that direction?
 * That is, is the sum of their constant terms smaller than "bound"?
 *
 * "tmp" is a temporary location that can be used to store the sum.
 */
static int constraint_pair_has_bound(__isl_keep isl_basic_map *bmap,
  int i, int j, isl_int bound, isl_int *tmp)
{
  isl_int_add(*tmp, bmap->ineq[i][0], bmap->ineq[j][0]);
  return isl_int_abs_lt(*tmp, bound);
}
 
/* Return the position of an inequality constraint in "bmap"
 * that together with inequality constraint "ineq" forms
 * a pair of opposite constraints that allow at most "bound" values
 * in their shared direction and that appears before "ineq".
 * Return a position beyond the number of inequality constraints
 * if no such constraint can be found.
 *
 * The constraints of "bmap" are assumed to have been sorted.
 * This means that as soon as a constraint is found where the value
 * of the last coefficient (in absolute value) is different from that of "ineq",
 * no opposite constraint can be found.
 * It also means that only the coefficients up to this last coefficient
 * need to be compared.
 *
 * "pos" is the position of a coefficient that is known to be non-zero.
 * If no such position is known a priori, then the value 0 can be passed in.
 * "len" is the number of (relevant) coefficients in the constraints.
 * "tmp" is a temporary location that can be used to store the sum.
 */
static isl_size find_earlier_constraint_in_pair(__isl_keep isl_basic_map *bmap,
  int ineq, int pos, int len, isl_int bound, isl_int *tmp)
{
  int j;
  int last;
  isl_size n_ineq;
 
  n_ineq = isl_basic_map_n_inequality(bmap);
  if (n_ineq < 0)
    return isl_size_error;
 
  last = extend_last_non_zero(bmap, ineq, pos, len);
 
  for (j = ineq - 1; j >= 0; --j) {
    if (!isl_int_abs_eq(bmap->ineq[ineq][1 + last],
            bmap->ineq[j][1 + last]))
      return n_ineq;
    if (!is_constraint_pair(bmap, ineq, j, last + 1))
      continue;
    if (constraint_pair_has_bound(bmap, ineq, j, bound, tmp))
      return j;
    return n_ineq;
  }
 
  return n_ineq;
}
 
/* Return the position of an inequality constraint in "bmap"
 * that together with inequality constraint "ineq" forms
 * a pair of opposite constraints that allow at most "bound" values
 * in their shared direction and that appears after "ineq".
 * Return a position beyond the number of inequality constraints
 * if no such constraint can be found.
 *
 * The constraints of "bmap" are assumed to have been sorted.
 * This means that as soon as a constraint is found where the value
 * of the last coefficient (in absolute value) is different from that of "ineq",
 * no opposite constraint can be found.
 * It also means that only the coefficients up to this last coefficient
 * need to be compared.
 *
 * "pos" is the position of a coefficient that is known to be non-zero.
 * If no such position is known a priori, then the value 0 can be passed in.
 * "len" is the number of (relevant) coefficients in the constraints.
 * "tmp" is a temporary location that can be used to store the sum.
 */
static isl_size find_later_constraint_in_pair(__isl_keep isl_basic_map *bmap,
  int ineq, int pos, int len, isl_int bound, isl_int *tmp)
{
  int j;
  int last;
  isl_size n_ineq;
 
  n_ineq = isl_basic_map_n_inequality(bmap);
  if (n_ineq < 0)
    return isl_size_error;
 
  last = extend_last_non_zero(bmap, ineq, pos, len);
 
  for (j = ineq + 1; j < n_ineq; ++j) {
    if (!isl_int_abs_eq(bmap->ineq[ineq][1 + last],
            bmap->ineq[j][1 + last]))
      return n_ineq;
    if (isl_seq_any_non_zero(bmap->ineq[j] + 1 + last + 1,
          len - (last + 1)))
      return n_ineq;
    if (!is_constraint_pair(bmap, ineq, j, last + 1))
      continue;
    if (constraint_pair_has_bound(bmap, ineq, j, bound, tmp))
      return j;
    return n_ineq;
  }
 
  return n_ineq;
}
 
/* Swap divs "a" and "b" in "bmap" (without modifying any of the constraints
 * of "bmap").
 */
static void swap_div(__isl_keep isl_basic_map *bmap, int a, int b)
{
  isl_int *t = bmap->div[a];
  bmap->div[a] = bmap->div[b];
  bmap->div[b] = t;
}
 
/* Swap divs "a" and "b" in "bmap" and adjust the constraints and
 * div definitions accordingly.
 */
__isl_give isl_basic_map *isl_basic_map_swap_div(__isl_take isl_basic_map *bmap,
  int a, int b)
{
  int i;
  isl_size off;
 
  off = isl_basic_map_var_offset(bmap, isl_dim_div);
  if (off < 0)
    return isl_basic_map_free(bmap);
 
  swap_div(bmap, a, b);
 
  for (i = 0; i < bmap->n_eq; ++i)
    isl_int_swap(bmap->eq[i][1+off+a], bmap->eq[i][1+off+b]);
 
  for (i = 0; i < bmap->n_ineq; ++i)
    isl_int_swap(bmap->ineq[i][1+off+a], bmap->ineq[i][1+off+b]);
 
  for (i = 0; i < bmap->n_div; ++i)
    isl_int_swap(bmap->div[i][1+1+off+a], bmap->div[i][1+1+off+b]);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
 
  return bmap;
}
 
static void constraint_drop_vars(isl_int *c, unsigned n, unsigned rem)
{
  isl_seq_cpy(c, c + n, rem);
  isl_seq_clr(c + rem, n);
}
 
/* Drop n dimensions starting at first.
 *
 * In principle, this frees up some extra variables as the number
 * of columns remains constant, but we would have to extend
 * the div array too as the number of rows in this array is assumed
 * to be equal to extra.
 */
__isl_give isl_basic_set *isl_basic_set_drop_dims(
  __isl_take isl_basic_set *bset, unsigned first, unsigned n)
{
  return isl_basic_map_drop(bset_to_bmap(bset), isl_dim_set, first, n);
}
 
/* Move "n" divs starting at "first" to the end of the list of divs.
 */
static __isl_give isl_basic_map *move_divs_last(__isl_take isl_basic_map *bmap,
  unsigned first, unsigned n)
{
  isl_int **div;
  int i;
 
  if (first + n == bmap->n_div)
    return bmap;
 
  div = isl_alloc_array(bmap->ctx, isl_int *, n);
  if (!div)
    goto error;
  for (i = 0; i < n; ++i)
    div[i] = bmap->div[first + i];
  for (i = 0; i < bmap->n_div - first - n; ++i)
    bmap->div[first + i] = bmap->div[first + n + i];
  for (i = 0; i < n; ++i)
    bmap->div[bmap->n_div - n + i] = div[i];
  free(div);
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
#undef TYPE
#define TYPE  isl_map
static
#include "check_type_range_templ.c"
 
/* Check that there are "n" dimensions of type "type" starting at "first"
 * in "set".
 */
isl_stat isl_set_check_range(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_map_check_range(set_to_map(set), type, first, n);
}
 
/* Drop "n" dimensions of type "type" starting at "first".
 * Perform the core computation, without cowing or
 * simplifying and finalizing the result.
 *
 * In principle, this frees up some extra variables as the number
 * of columns remains constant, but we would have to extend
 * the div array too as the number of rows in this array is assumed
 * to be equal to extra.
 */
__isl_give isl_basic_map *isl_basic_map_drop_core(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type,
  unsigned first, unsigned n)
{
  int i;
  unsigned offset;
  unsigned left;
  isl_size total;
 
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_basic_map_free(bmap);
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
 
  offset = isl_basic_map_offset(bmap, type) + first;
  left = total - (offset - 1) - n;
  for (i = 0; i < bmap->n_eq; ++i)
    constraint_drop_vars(bmap->eq[i]+offset, n, left);
 
  for (i = 0; i < bmap->n_ineq; ++i)
    constraint_drop_vars(bmap->ineq[i]+offset, n, left);
 
  for (i = 0; i < bmap->n_div; ++i)
    constraint_drop_vars(bmap->div[i]+1+offset, n, left);
 
  if (type == isl_dim_div) {
    bmap = move_divs_last(bmap, first, n);
    if (!bmap)
      return NULL;
    if (isl_basic_map_free_div(bmap, n) < 0)
      return isl_basic_map_free(bmap);
  } else
    bmap->dim = isl_space_drop_dims(bmap->dim, type, first, n);
  if (!bmap->dim)
    return isl_basic_map_free(bmap);
 
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_REDUNDANT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_REDUCED_COEFFICIENTS);
  return bmap;
}
 
/* Drop "n" dimensions of type "type" starting at "first".
 *
 * In principle, this frees up some extra variables as the number
 * of columns remains constant, but we would have to extend
 * the div array too as the number of rows in this array is assumed
 * to be equal to extra.
 */
__isl_give isl_basic_map *isl_basic_map_drop(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  if (!bmap)
    return NULL;
  if (n == 0 && !isl_space_is_named_or_nested(bmap->dim, type))
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
 
  bmap = isl_basic_map_drop_core(bmap, type, first, n);
 
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
}
 
__isl_give isl_basic_set *isl_basic_set_drop(__isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return bset_from_bmap(isl_basic_map_drop(bset_to_bmap(bset),
              type, first, n));
}
 
/* No longer consider "map" to be normalized.
 */
static __isl_give isl_map *isl_map_unmark_normalized(__isl_take isl_map *map)
{
  if (!map)
    return NULL;
  ISL_F_CLR(map, ISL_MAP_NORMALIZED);
  return map;
}
 
__isl_give isl_map *isl_map_drop(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
  isl_space *space;
 
  if (isl_map_check_range(map, type, first, n) < 0)
    return isl_map_free(map);
 
  if (n == 0 && !isl_space_is_named_or_nested(map->dim, type))
    return map;
  map = isl_map_cow(map);
  if (!map)
    goto error;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_drop(map->p[i], type, first, n);
    if (!map->p[i])
      goto error;
  }
  map = isl_map_unmark_normalized(map);
 
  space = isl_map_take_space(map);
  space = isl_space_drop_dims(space, type, first, n);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_drop(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return set_from_map(isl_map_drop(set_to_map(set), type, first, n));
}
 
/* Drop the integer division at position "div", which is assumed
 * not to appear in any of the constraints or
 * in any of the other integer divisions.
 *
 * Since the integer division is redundant, there is no need to cow.
 */
__isl_give isl_basic_map *isl_basic_map_drop_div(
  __isl_take isl_basic_map *bmap, unsigned div)
{
  return isl_basic_map_drop_core(bmap, isl_dim_div, div, 1);
}
 
/* Eliminate the specified n dimensions starting at first from the
 * constraints, without removing the dimensions from the space.
 * If the set is rational, the dimensions are eliminated using Fourier-Motzkin.
 */
__isl_give isl_map *isl_map_eliminate(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
 
  if (n == 0)
    return map;
 
  if (isl_map_check_range(map, type, first, n) < 0)
    return isl_map_free(map);
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_eliminate(map->p[i], type, first, n);
    if (!map->p[i])
      goto error;
  }
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
/* Eliminate the specified n dimensions starting at first from the
 * constraints, without removing the dimensions from the space.
 * If the set is rational, the dimensions are eliminated using Fourier-Motzkin.
 */
__isl_give isl_set *isl_set_eliminate(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return set_from_map(isl_map_eliminate(set_to_map(set), type, first, n));
}
 
/* Eliminate the specified n dimensions starting at first from the
 * constraints, without removing the dimensions from the space.
 * If the set is rational, the dimensions are eliminated using Fourier-Motzkin.
 */
__isl_give isl_set *isl_set_eliminate_dims(__isl_take isl_set *set,
  unsigned first, unsigned n)
{
  return isl_set_eliminate(set, isl_dim_set, first, n);
}
 
__isl_give isl_basic_map *isl_basic_map_remove_divs(
  __isl_take isl_basic_map *bmap)
{
  isl_size v_div;
 
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  if (v_div < 0)
    return isl_basic_map_free(bmap);
  bmap = isl_basic_map_eliminate_vars(bmap, v_div, bmap->n_div);
  if (!bmap)
    return NULL;
  bmap->n_div = 0;
  return isl_basic_map_finalize(bmap);
}
 
__isl_give isl_basic_set *isl_basic_set_remove_divs(
  __isl_take isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_remove_divs(bset_to_bmap(bset)));
}
 
__isl_give isl_map *isl_map_remove_divs(__isl_take isl_map *map)
{
  int i;
 
  if (!map)
    return NULL;
  if (map->n == 0)
    return map;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
  
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_remove_divs(map->p[i]);
    if (!map->p[i])
      goto error;
  }
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_remove_divs(__isl_take isl_set *set)
{
  return isl_map_remove_divs(set);
}
 
__isl_give isl_basic_map *isl_basic_map_remove_dims(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type,
  unsigned first, unsigned n)
{
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_basic_map_free(bmap);
  if (n == 0 && !isl_space_is_named_or_nested(bmap->dim, type))
    return bmap;
  bmap = isl_basic_map_eliminate_vars(bmap,
      isl_basic_map_offset(bmap, type) - 1 + first, n);
  if (!bmap)
    return bmap;
  if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY) && type == isl_dim_div)
    return bmap;
  bmap = isl_basic_map_drop(bmap, type, first, n);
  return bmap;
}
 
/* Does the local variable "div" of "bmap" have a known expression
 * that involves the "n" variables starting at "first"?
 */
isl_bool isl_basic_map_div_expr_involves_vars(__isl_keep isl_basic_map *bmap,
  int div, unsigned first, unsigned n)
{
  isl_bool unknown;
 
  unknown = isl_basic_map_div_is_marked_unknown(bmap, div);
  if (unknown < 0 || unknown)
    return isl_bool_not(unknown);
  if (isl_seq_any_non_zero(bmap->div[div] + 1 + 1 + first, n))
    return isl_bool_true;
 
  return isl_bool_false;
}
 
/* Return true if the definition of the given div (recursively) involves
 * any of the given variables.
 */
static isl_bool div_involves_vars(__isl_keep isl_basic_map *bmap, int div,
  unsigned first, unsigned n)
{
  int i;
  isl_bool involves;
  isl_size n_div, v_div;
 
  involves = isl_basic_map_div_expr_involves_vars(bmap, div, first, n);
  if (involves < 0 || involves)
    return involves;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  if (n_div < 0 || v_div < 0)
    return isl_bool_error;
  for (i = n_div - 1; i >= 0; --i) {
    isl_bool involves;
 
    if (isl_int_is_zero(bmap->div[div][1 + 1 + v_div + i]))
      continue;
    involves = div_involves_vars(bmap, i, first, n);
    if (involves < 0 || involves)
      return involves;
  }
 
  return isl_bool_false;
}
 
/* Does the definition of any integer division involve
 * any of the given variables?
 */
isl_bool isl_basic_map_any_div_involves_vars(__isl_keep isl_basic_map *bmap,
  unsigned first, unsigned n)
{
  int i;
  isl_size n_div;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_div < 0)
    return isl_bool_error;
 
  for (i = 0; i < n_div; ++i) {
    isl_bool has;
 
    has = isl_basic_map_div_expr_involves_vars(bmap, i, first, n);
    if (has < 0 || has)
      return has;
  }
 
  return isl_bool_false;
}
 
/* Try and add a lower and/or upper bound on "div" to "bmap"
 * based on inequality "i".
 * "total" is the total number of variables (excluding the divs).
 * "v" is a temporary object that can be used during the calculations.
 * If "lb" is set, then a lower bound should be constructed.
 * If "ub" is set, then an upper bound should be constructed.
 *
 * The calling function has already checked that the inequality does not
 * reference "div", but we still need to check that the inequality is
 * of the right form.  We'll consider the case where we want to construct
 * a lower bound.  The construction of upper bounds is similar.
 *
 * Let "div" be of the form
 *
 *  q = floor((a + f(x))/d)
 *
 * We essentially check if constraint "i" is of the form
 *
 *  b + f(x) >= 0
 *
 * so that we can use it to derive a lower bound on "div".
 * However, we allow a slightly more general form
 *
 *  b + g(x) >= 0
 *
 * with the condition that the coefficients of g(x) - f(x) are all
 * divisible by d.
 * Rewriting this constraint as
 *
 *  0 >= -b - g(x)
 *
 * adding a + f(x) to both sides and dividing by d, we obtain
 *
 *  (a + f(x))/d >= (a-b)/d + (f(x)-g(x))/d
 *
 * Taking the floor on both sides, we obtain
 *
 *  q >= floor((a-b)/d) + (f(x)-g(x))/d
 *
 * or
 *
 *  (g(x)-f(x))/d + ceil((b-a)/d) + q >= 0
 *
 * In the case of an upper bound, we construct the constraint
 *
 *  (g(x)+f(x))/d + floor((b+a)/d) - q >= 0
 *
 */
static __isl_give isl_basic_map *insert_bounds_on_div_from_ineq(
  __isl_take isl_basic_map *bmap, int div, int i,
  unsigned total, isl_int v, int lb, int ub)
{
  int j;
 
  for (j = 0; (lb || ub) && j < total + bmap->n_div; ++j) {
    if (lb) {
      isl_int_sub(v, bmap->ineq[i][1 + j],
          bmap->div[div][1 + 1 + j]);
      lb = isl_int_is_divisible_by(v, bmap->div[div][0]);
    }
    if (ub) {
      isl_int_add(v, bmap->ineq[i][1 + j],
          bmap->div[div][1 + 1 + j]);
      ub = isl_int_is_divisible_by(v, bmap->div[div][0]);
    }
  }
  if (!lb && !ub)
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 0, lb + ub);
  if (lb) {
    int k = isl_basic_map_alloc_inequality(bmap);
    if (k < 0)
      goto error;
    for (j = 0; j < 1 + total + bmap->n_div; ++j) {
      isl_int_sub(bmap->ineq[k][j], bmap->ineq[i][j],
          bmap->div[div][1 + j]);
      isl_int_cdiv_q(bmap->ineq[k][j],
          bmap->ineq[k][j], bmap->div[div][0]);
    }
    isl_int_set_si(bmap->ineq[k][1 + total + div], 1);
  }
  if (ub) {
    int k = isl_basic_map_alloc_inequality(bmap);
    if (k < 0)
      goto error;
    for (j = 0; j < 1 + total + bmap->n_div; ++j) {
      isl_int_add(bmap->ineq[k][j], bmap->ineq[i][j],
          bmap->div[div][1 + j]);
      isl_int_fdiv_q(bmap->ineq[k][j],
          bmap->ineq[k][j], bmap->div[div][0]);
    }
    isl_int_set_si(bmap->ineq[k][1 + total + div], -1);
  }
 
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* This function is called right before "div" is eliminated from "bmap"
 * using Fourier-Motzkin.
 * Look through the constraints of "bmap" for constraints on the argument
 * of the integer division and use them to construct constraints on the
 * integer division itself.  These constraints can then be combined
 * during the Fourier-Motzkin elimination.
 * Note that it is only useful to introduce lower bounds on "div"
 * if "bmap" already contains upper bounds on "div" as the newly
 * introduce lower bounds can then be combined with the pre-existing
 * upper bounds.  Similarly for upper bounds.
 * We therefore first check if "bmap" contains any lower and/or upper bounds
 * on "div".
 *
 * It is interesting to note that the introduction of these constraints
 * can indeed lead to more accurate results, even when compared to
 * deriving constraints on the argument of "div" from constraints on "div".
 * Consider, for example, the set
 *
 *  { [i,j,k] : 3 + i + 2j >= 0 and 2 * [(i+2j)/4] <= k }
 *
 * The second constraint can be rewritten as
 *
 *  2 * [(-i-2j+3)/4] + k >= 0
 *
 * from which we can derive
 *
 *  -i - 2j + 3 >= -2k
 *
 * or
 *
 *  i + 2j <= 3 + 2k
 *
 * Combined with the first constraint, we obtain
 *
 *  -3 <= 3 + 2k  or  k >= -3
 *
 * If, on the other hand we derive a constraint on [(i+2j)/4] from
 * the first constraint, we obtain
 *
 *  [(i + 2j)/4] >= [-3/4] = -1
 *
 * Combining this constraint with the second constraint, we obtain
 *
 *  k >= -2
 */
static __isl_give isl_basic_map *insert_bounds_on_div(
  __isl_take isl_basic_map *bmap, int div)
{
  int i;
  int check_lb, check_ub;
  isl_int v;
  isl_size v_div;
 
  if (!bmap)
    return NULL;
 
  if (isl_int_is_zero(bmap->div[div][0]))
    return bmap;
 
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  if (v_div < 0)
    return isl_basic_map_free(bmap);
 
  check_lb = 0;
  check_ub = 0;
  for (i = 0; (!check_lb || !check_ub) && i < bmap->n_ineq; ++i) {
    int s = isl_int_sgn(bmap->ineq[i][1 + v_div + div]);
    if (s > 0)
      check_ub = 1;
    if (s < 0)
      check_lb = 1;
  }
 
  if (!check_lb && !check_ub)
    return bmap;
 
  isl_int_init(v);
 
  for (i = 0; bmap && i < bmap->n_ineq; ++i) {
    if (!isl_int_is_zero(bmap->ineq[i][1 + v_div + div]))
      continue;
 
    bmap = insert_bounds_on_div_from_ineq(bmap, div, i, v_div, v,
              check_lb, check_ub);
  }
 
  isl_int_clear(v);
 
  return bmap;
}
 
/* Remove all divs (recursively) involving any of the given variables
 * in their definitions.
 */
static __isl_give isl_basic_map *remove_divs_involving_vars(
  __isl_take isl_basic_map *bmap, unsigned first, unsigned n)
{
  int i;
 
  for (i = bmap->n_div - 1; i >= 0; --i) {
    isl_bool involves;
 
    involves = div_involves_vars(bmap, i, first, n);
    if (involves < 0)
      return isl_basic_map_free(bmap);
    if (!involves)
      continue;
    bmap = insert_bounds_on_div(bmap, i);
    bmap = isl_basic_map_remove_dims(bmap, isl_dim_div, i, 1);
    if (!bmap)
      return NULL;
    i = bmap->n_div;
  }
 
  return bmap;
}
 
/* Data structure for communicating data between detect_mod and
 * substitute_div_mod.
 *
 * "pos" is the position of the variable that is being examined.
 *
 * "lower_f" is the index of the constraint
 *  -f(x) + m i + t m n h(alpha) >= 0
 * "lower_g" is the index of the constraint
 *  -g(x) + i >= 0
 * "m" and "n" correspond to the values in the first constraint.
 * "sum" is a temporary variable that is used internally inside detect_mod.
 */
struct isl_detect_mod_data {
  unsigned pos;
 
  int lower_f;
  int lower_g;
 
  isl_int m;
  isl_int n;
 
  isl_int sum;
};
 
/* Initialize "data".
 */
static void isl_detect_mod_data_init(struct isl_detect_mod_data *data)
{
  isl_int_init(data->m);
  isl_int_init(data->n);
  isl_int_init(data->sum);
}
 
/* Free any memory allocated by "data".
 */
static void isl_detect_mod_data_clear(struct isl_detect_mod_data *data)
{
  isl_int_clear(data->sum);
  isl_int_clear(data->n);
  isl_int_clear(data->m);
}
 
/* Is the variable at position data->pos
 * equal to a specific case of a nested modulo?
 *
 * In particular, look for two pairs of constraints
 *
 *  -f(x) + m i + t m n h(alpha) >= 0
 *   f(x) - m i - t m n h(alpha) + c >= 0
 *
 * and
 *
 *  -g(x) + i >= 0
 *   g(x) - i + d >= 0
 *
 * where f(x) and g(x) are expressions in the other variables,
 * excluding local variables,
 * h(alpha) is a non-zero expression in the local variable,
 * t is +1 or -1,
 * c < m, and
 * d < n.
 *
 * If these pairs of constraints are found,
 * then store the constraint index of the first f-constraint in data->lower_f,
 * the index of the first g-constraint in data->lower_g and
 * the values m and n in data->m and data->n.
 *
 * The constraints are assumed to have been sorted,
 * which means that the constraints in a pair are close to each other.
 * The sorting also means that the f-constraints appear
 * after the g-constraints.
 */
static isl_bool detect_mod(__isl_keep isl_basic_map *bmap,
  struct isl_detect_mod_data *data)
{
  int i;
  isl_size j;
  isl_size n_ineq;
  isl_size v_div, n_div, total;
 
  n_ineq = isl_basic_map_n_inequality(bmap);
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (n_ineq < 0 || v_div < 0 || n_div < 0 || total < 0)
    return isl_bool_error;
  if (n_ineq < 4)
    return isl_bool_false;
 
  for (i = n_ineq - 1; i >= 1; --i) {
    isl_seq_gcd(bmap->ineq[i] + 1 + v_div, n_div, &data->n);
    if (isl_int_is_zero(data->n))
      return isl_bool_false;
    isl_int_abs(data->m, bmap->ineq[i][1 + data->pos]);
    j = find_earlier_constraint_in_pair(bmap, i, data->pos, total,
              data->m, &data->sum);
    if (j < 0)
      return isl_bool_error;
    if (j >= n_ineq)
      continue;
    if (!isl_int_is_divisible_by(data->n, data->m))
      continue;
    if (isl_int_is_pos(bmap->ineq[i][1 + data->pos]))
      data->lower_f = i;
    else
      data->lower_f = j;
    isl_int_divexact(data->n, data->n, data->m);
    isl_int_abs(data->n, data->n);
    break;
  }
  if (i < 1)
    return isl_bool_false;
  for (i = j - 1; i >= 1; --i) {
    if (isl_seq_any_non_zero(bmap->ineq[i] + 1 + v_div, n_div))
      continue;
    if (!isl_int_is_one(bmap->ineq[i][1 + data->pos]) &&
        !isl_int_is_negone(bmap->ineq[i][1 + data->pos]))
      continue;
    j = find_earlier_constraint_in_pair(bmap, i, data->pos, v_div,
              data->m, &data->sum);
    if (j < 0)
      return isl_bool_error;
    if (j >= n_ineq)
      continue;
    if (isl_int_is_pos(bmap->ineq[i][1 + data->pos]))
      data->lower_g = i;
    else
      data->lower_g = j;
    break;
  }
  if (i < 1)
    return isl_bool_false;
  return isl_bool_true;
}
 
/* Given an affine expression "aff" in the variables of "bset" that expresses
 * a bound on the variable at position "pos" in terms of the other variables,
 * extract this expression as a function of those other variables,
 * excluding any local variables.
 */
static __isl_give isl_aff *extract_aff(
  __isl_keep isl_basic_set *bset, isl_int *aff, int pos)
{
  isl_size dim;
  isl_ctx *ctx;
  isl_vec *v;
  isl_space *space;
  isl_local_space *ls;
 
  space = isl_basic_set_peek_space(bset);
  dim = isl_space_dim(space, isl_dim_all);
  if (dim < 0)
    return NULL;
  ls = isl_local_space_from_space(isl_space_copy(space));
  ctx = isl_basic_set_get_ctx(bset);
  v = extract_bound_from_constraint(ctx, aff, dim, pos);
  return isl_aff_alloc_vec(ls, v);
}
 
/* Given that inequality "ineq" of "bset" expresses a lower bound
 * on the variable at position "pos" in terms of the other variables,
 * extract this lower bound as a function of those other variables,
 * excluding any local variables.
 */
static __isl_give isl_aff *extract_lower_bound_aff(
  __isl_keep isl_basic_set *bset, int ineq, int pos)
{
  if (!bset)
    return NULL;
  return extract_aff(bset, bset->ineq[ineq], pos);
}
 
/* Given that there are two pairs of constraints
 *
 *  -f(x) + m i + t m n h(alpha) >= 0
 *   f(x) - m i - t m n h(alpha) + c >= 0
 *
 * and
 *
 *  -g(x) + i >= 0
 *   g(x) - i + d >= 0
 *
 * where f(x) and g(x) are expressions in the other variables,
 * excluding local variables,
 * h(alpha) is a non-zero expression in the local variable,
 * t is +1 or -1,
 * c < m, and
 * d < n,
 * derive an expression for i and plug that into "bmap".
 *
 * In particular, the first pair of constraints implies
 *
 *  0 <= (-f(x) + m i) % (m n) <= c
 *  0 <= (m floor(-f(x)/m) + (-f(x)) mod m + m i) % (m n) <= c
 *  0 <= (m floor(-f(x)/m) + m i) % (m n) + (-f(x)) mod m <= c
 *  0 <= m ((floor(-f(x)/m) + i) % n) + (-f(x)) mod m <= c
 *
 * or
 *
 *  (floor(-f(x)/m) + i) % n = 0
 *
 * because c < m, which can be rewritten to
 *
 *  (floor(-f(x)/m) + g(x) - g(x) + i) % n = 0
 *
 * or
 *
 *  (-g(x) + i) % n = (-floor(-f(x)/m) - g(x)) % n
 *
 * Since 0 <= -g(x) + i <= d < n,
 *
 *  -g(x) + i = (-floor(-f(x)/m) - g(x)) % n
 *
 * or
 *
 *  i = (-floor(-f(x)/m) - g(x)) % n + g(x)
 *
 * Note that the lower bounds on i derived from the original constraints are
 *
 *  i >= f(x)/m
 *  i >= g(x)
 *
 * (ignoring local variables).
 *
 * The expression for i is plugged into "bmap", which results
 * in a basic map equivalent to "bmap" given i is equal to the expression,
 * so an equality constraint is added to ensure the meaning is preserved.
 */
static __isl_give isl_basic_map *substitute_div_mod(
  __isl_take isl_basic_map *bmap, unsigned pos,
  struct isl_detect_mod_data *data)
{
  isl_ctx *ctx;
  isl_basic_set *bset, *eq;
  isl_space *space;
  isl_aff *g, *f, *aff, *it;
  isl_val *v;
  isl_size v_in;
  isl_multi_aff *ma;
 
  v_in = isl_basic_map_var_offset(bmap, isl_dim_in);
  if (v_in < 0)
    return isl_basic_map_free(bmap);
 
  ctx = isl_basic_map_get_ctx(bmap);
  bset = isl_basic_map_wrap(bmap);
  space = isl_basic_set_get_space(bset);
  g = extract_lower_bound_aff(bset, data->lower_g, pos);
  f = extract_lower_bound_aff(bset, data->lower_f, pos);
  ma = isl_space_identity_multi_aff_on_domain(space);
  aff = isl_aff_neg(isl_aff_floor(isl_aff_neg(f)));
  aff = isl_aff_sub(aff, isl_aff_copy(g));
  v = isl_val_int_from_isl_int(ctx, data->n);
  aff = isl_aff_mod_val(aff, v);
  aff = isl_aff_add(aff, g);
  it = isl_multi_aff_get_at(ma, pos - v_in);
  eq = isl_aff_eq_basic_set(it, isl_aff_copy(aff));
  ma = isl_multi_aff_set_at(ma, pos - v_in, aff);
  bset = isl_basic_set_preimage_multi_aff(bset, ma);
  bset = isl_basic_set_intersect(bset, eq);
  return isl_basic_set_unwrap(bset);
}
 
/* Remove all divs (recursively) involving any of the given dimensions
 * in their definitions.
 *
 * If it is a single input or output dimension that
 * should not appear in any integer division expression and
 * if there is indeed an integer division expression
 * involving that dimension, then check if there are any constraints
 * that imply that the given dimension is equal to some expression
 * in the other dimensions.
 * If so, plug in that expression for the given dimension
 * so that the integer division expressions no longer
 * involve that dimension.
 */
__isl_give isl_basic_map *isl_basic_map_remove_divs_involving_dims(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  isl_size off;
  isl_bool used;
  isl_bool found;
  struct isl_detect_mod_data data;
 
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_basic_map_free(bmap);
  off = isl_basic_map_var_offset(bmap, type);
  if (off < 0)
    return isl_basic_map_free(bmap);
  first += off;
 
  if (type == isl_dim_param || type == isl_dim_div || n != 1)
    return remove_divs_involving_vars(bmap, first, n);
  used = isl_basic_map_any_div_involves_vars(bmap, first, n);
  if (used < 0)
    return isl_basic_map_free(bmap);
  if (!used)
    return bmap;
  bmap = isl_basic_map_sort_constraints(bmap);
  isl_detect_mod_data_init(&data);
  data.pos = first;
  found = detect_mod(bmap, &data);
  if (!found)
    bmap = remove_divs_involving_vars(bmap, first, n);
  else
    bmap = substitute_div_mod(bmap, first, &data);
  isl_detect_mod_data_clear(&data);
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_remove_divs_involving_dims(
  __isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_basic_map_remove_divs_involving_dims(bset, type, first, n);
}
 
__isl_give isl_map *isl_map_remove_divs_involving_dims(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
 
  if (!map)
    return NULL;
  if (map->n == 0)
    return map;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_remove_divs_involving_dims(map->p[i],
                type, first, n);
    if (!map->p[i])
      goto error;
  }
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_remove_divs_involving_dims(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return set_from_map(isl_map_remove_divs_involving_dims(set_to_map(set),
                    type, first, n));
}
 
/* Does the description of "bmap" depend on the specified dimensions?
 * We also check whether the dimensions appear in any of the div definitions.
 * In principle there is no need for this check.  If the dimensions appear
 * in a div definition, they also appear in the defining constraints of that
 * div.
 */
isl_bool isl_basic_map_involves_dims(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
 
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_bool_error;
 
  first += isl_basic_map_offset(bmap, type);
  for (i = 0; i < bmap->n_eq; ++i)
    if (isl_seq_any_non_zero(bmap->eq[i] + first, n))
      return isl_bool_true;
  for (i = 0; i < bmap->n_ineq; ++i)
    if (isl_seq_any_non_zero(bmap->ineq[i] + first, n))
      return isl_bool_true;
  for (i = 0; i < bmap->n_div; ++i) {
    if (isl_int_is_zero(bmap->div[i][0]))
      continue;
    if (isl_seq_any_non_zero(bmap->div[i] + 1 + first, n))
      return isl_bool_true;
  }
 
  return isl_bool_false;
}
 
isl_bool isl_map_involves_dims(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
 
  if (isl_map_check_range(map, type, first, n) < 0)
    return isl_bool_error;
 
  for (i = 0; i < map->n; ++i) {
    isl_bool involves = isl_basic_map_involves_dims(map->p[i],
                  type, first, n);
    if (involves < 0 || involves)
      return involves;
  }
 
  return isl_bool_false;
}
 
isl_bool isl_basic_set_involves_dims(__isl_keep isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_basic_map_involves_dims(bset, type, first, n);
}
 
isl_bool isl_set_involves_dims(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_map_involves_dims(set, type, first, n);
}
 
/* Does "bset" involve any local variables, i.e., integer divisions?
 */
static isl_bool isl_basic_set_involves_locals(__isl_keep isl_basic_set *bset)
{
  isl_size n;
 
  n = isl_basic_set_dim(bset, isl_dim_div);
  if (n < 0)
    return isl_bool_error;
  return isl_bool_ok(n > 0);
}
 
/* isl_set_every_basic_set callback that checks whether "bset"
 * is free of local variables.
 */
static isl_bool basic_set_no_locals(__isl_keep isl_basic_set *bset, void *user)
{
  return isl_bool_not(isl_basic_set_involves_locals(bset));
}
 
/* Does "set" involve any local variables, i.e., integer divisions?
 */
isl_bool isl_set_involves_locals(__isl_keep isl_set *set)
{
  isl_bool no_locals;
 
  no_locals = isl_set_every_basic_set(set, &basic_set_no_locals, NULL);
  return isl_bool_not(no_locals);
}
 
/* Drop all constraints in bmap that involve any of the dimensions
 * first to first+n-1.
 * This function only performs the actual removal of constraints.
 *
 * This function should not call finalize since it is used by
 * remove_redundant_divs, which in turn is called by isl_basic_map_finalize.
 */
__isl_give isl_basic_map *isl_basic_map_drop_constraints_involving(
  __isl_take isl_basic_map *bmap, unsigned first, unsigned n)
{
  int i;
 
  if (n == 0)
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
 
  if (!bmap)
    return NULL;
 
  for (i = bmap->n_eq - 1; i >= 0; --i) {
    if (!isl_seq_any_non_zero(bmap->eq[i] + 1 + first, n))
      continue;
    if (isl_basic_map_drop_equality(bmap, i) < 0)
      return isl_basic_map_free(bmap);
  }
 
  for (i = bmap->n_ineq - 1; i >= 0; --i) {
    if (!isl_seq_any_non_zero(bmap->ineq[i] + 1 + first, n))
      continue;
    if (isl_basic_map_drop_inequality(bmap, i) < 0)
      return isl_basic_map_free(bmap);
  }
 
  return bmap;
}
 
/* Drop all constraints in bset that involve any of the dimensions
 * first to first+n-1.
 * This function only performs the actual removal of constraints.
 */
__isl_give isl_basic_set *isl_basic_set_drop_constraints_involving(
  __isl_take isl_basic_set *bset, unsigned first, unsigned n)
{
  return isl_basic_map_drop_constraints_involving(bset, first, n);
}
 
/* Drop all constraints in bmap that do not involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_basic_map *isl_basic_map_drop_constraints_not_involving_dims(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
 
  if (n == 0) {
    isl_space *space = isl_basic_map_get_space(bmap);
    isl_basic_map_free(bmap);
    return isl_basic_map_universe(space);
  }
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
 
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_basic_map_free(bmap);
 
  first += isl_basic_map_offset(bmap, type) - 1;
 
  for (i = bmap->n_eq - 1; i >= 0; --i) {
    if (isl_seq_any_non_zero(bmap->eq[i] + 1 + first, n))
      continue;
    if (isl_basic_map_drop_equality(bmap, i) < 0)
      return isl_basic_map_free(bmap);
  }
 
  for (i = bmap->n_ineq - 1; i >= 0; --i) {
    if (isl_seq_any_non_zero(bmap->ineq[i] + 1 + first, n))
      continue;
    if (isl_basic_map_drop_inequality(bmap, i) < 0)
      return isl_basic_map_free(bmap);
  }
 
  bmap = isl_basic_map_add_known_div_constraints(bmap);
  return bmap;
}
 
/* Drop all constraints in bset that do not involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_basic_set *isl_basic_set_drop_constraints_not_involving_dims(
  __isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_basic_map_drop_constraints_not_involving_dims(bset,
                  type, first, n);
}
 
/* Drop all constraints in bmap that involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_basic_map *isl_basic_map_drop_constraints_involving_dims(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  if (!bmap)
    return NULL;
  if (n == 0)
    return bmap;
 
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_basic_map_free(bmap);
 
  bmap = isl_basic_map_remove_divs_involving_dims(bmap, type, first, n);
  first += isl_basic_map_offset(bmap, type) - 1;
  bmap = isl_basic_map_drop_constraints_involving(bmap, first, n);
  bmap = isl_basic_map_add_known_div_constraints(bmap);
  return bmap;
}
 
/* Drop all constraints in bset that involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_basic_set *isl_basic_set_drop_constraints_involving_dims(
  __isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_basic_map_drop_constraints_involving_dims(bset,
                  type, first, n);
}
 
/* Drop constraints from "map" by applying "drop" to each basic map.
 */
static __isl_give isl_map *drop_constraints(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n,
  __isl_give isl_basic_map *(*drop)(__isl_take isl_basic_map *bmap,
    enum isl_dim_type type, unsigned first, unsigned n))
{
  int i;
 
  if (isl_map_check_range(map, type, first, n) < 0)
    return isl_map_free(map);
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = drop(map->p[i], type, first, n);
    if (!map->p[i])
      return isl_map_free(map);
  }
 
  if (map->n > 1)
    ISL_F_CLR(map, ISL_MAP_DISJOINT);
 
  return map;
}
 
/* Drop all constraints in map that involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_map *isl_map_drop_constraints_involving_dims(
  __isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  if (n == 0)
    return map;
  return drop_constraints(map, type, first, n,
        &isl_basic_map_drop_constraints_involving_dims);
}
 
/* Drop all constraints in "map" that do not involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_map *isl_map_drop_constraints_not_involving_dims(
  __isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  if (n == 0) {
    isl_space *space = isl_map_get_space(map);
    isl_map_free(map);
    return isl_map_universe(space);
  }
  return drop_constraints(map, type, first, n,
          &isl_basic_map_drop_constraints_not_involving_dims);
}
 
/* Drop all constraints in set that involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_set *isl_set_drop_constraints_involving_dims(
  __isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_map_drop_constraints_involving_dims(set, type, first, n);
}
 
/* Drop all constraints in "set" that do not involve any of the dimensions
 * first to first + n - 1 of the given type.
 */
__isl_give isl_set *isl_set_drop_constraints_not_involving_dims(
  __isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return isl_map_drop_constraints_not_involving_dims(set, type, first, n);
}
 
/* Does local variable "div" of "bmap" have a complete explicit representation?
 * Having a complete explicit representation requires not only
 * an explicit representation, but also that all local variables
 * that appear in this explicit representation in turn have
 * a complete explicit representation.
 */
isl_bool isl_basic_map_div_is_known(__isl_keep isl_basic_map *bmap, int div)
{
  int i;
  unsigned div_offset = isl_basic_map_offset(bmap, isl_dim_div);
  isl_bool marked;
 
  marked = isl_basic_map_div_is_marked_unknown(bmap, div);
  if (marked < 0 || marked)
    return isl_bool_not(marked);
 
  for (i = bmap->n_div - 1; i >= 0; --i) {
    isl_bool known;
 
    if (isl_int_is_zero(bmap->div[div][1 + div_offset + i]))
      continue;
    known = isl_basic_map_div_is_known(bmap, i);
    if (known < 0 || !known)
      return known;
  }
 
  return isl_bool_true;
}
 
/* Remove all divs that are unknown or defined in terms of unknown divs.
 */
__isl_give isl_basic_map *isl_basic_map_remove_unknown_divs(
  __isl_take isl_basic_map *bmap)
{
  int i;
 
  if (!bmap)
    return NULL;
 
  for (i = bmap->n_div - 1; i >= 0; --i) {
    if (isl_basic_map_div_is_known(bmap, i))
      continue;
    bmap = isl_basic_map_remove_dims(bmap, isl_dim_div, i, 1);
    if (!bmap)
      return NULL;
    i = bmap->n_div;
  }
 
  return bmap;
}
 
/* Remove all divs that are unknown or defined in terms of unknown divs.
 */
__isl_give isl_basic_set *isl_basic_set_remove_unknown_divs(
  __isl_take isl_basic_set *bset)
{
  return isl_basic_map_remove_unknown_divs(bset);
}
 
__isl_give isl_map *isl_map_remove_unknown_divs(__isl_take isl_map *map)
{
  int i;
 
  if (!map)
    return NULL;
  if (map->n == 0)
    return map;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_remove_unknown_divs(map->p[i]);
    if (!map->p[i])
      goto error;
  }
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_remove_unknown_divs(__isl_take isl_set *set)
{
  return set_from_map(isl_map_remove_unknown_divs(set_to_map(set)));
}
 
__isl_give isl_basic_set *isl_basic_set_remove_dims(
  __isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  isl_basic_map *bmap = bset_to_bmap(bset);
  bmap = isl_basic_map_remove_dims(bmap, type, first, n);
  return bset_from_bmap(bmap);
}
 
__isl_give isl_map *isl_map_remove_dims(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
 
  if (n == 0)
    return map;
 
  map = isl_map_cow(map);
  if (isl_map_check_range(map, type, first, n) < 0)
    return isl_map_free(map);
  
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_eliminate_vars(map->p[i],
      isl_basic_map_offset(map->p[i], type) - 1 + first, n);
    if (!map->p[i])
      goto error;
  }
  map = isl_map_drop(map, type, first, n);
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_remove_dims(__isl_take isl_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  return set_from_map(isl_map_remove_dims(set_to_map(bset),
            type, first, n));
}
 
/* Project out n inputs starting at first using Fourier-Motzkin */
__isl_give isl_map *isl_map_remove_inputs(__isl_take isl_map *map,
  unsigned first, unsigned n)
{
  return isl_map_remove_dims(map, isl_dim_in, first, n);
}
 
void isl_basic_set_print_internal(__isl_keep isl_basic_set *bset,
  FILE *out, int indent)
{
  isl_printer *p;
 
  if (!bset) {
    fprintf(out, "null basic set\n");
    return;
  }
 
  fprintf(out, "%*s", indent, "");
  fprintf(out, "ref: %d, nparam: %d, dim: %d, extra: %d, flags: %x\n",
      bset->ref, bset->dim->nparam, bset->dim->n_out,
      bset->extra, bset->flags);
 
  p = isl_printer_to_file(isl_basic_set_get_ctx(bset), out);
  p = isl_printer_set_dump(p, 1);
  p = isl_printer_set_indent(p, indent);
  p = isl_printer_start_line(p);
  p = isl_printer_print_basic_set(p, bset);
  p = isl_printer_end_line(p);
  isl_printer_free(p);
}
 
void isl_basic_map_print_internal(__isl_keep isl_basic_map *bmap,
  FILE *out, int indent)
{
  isl_printer *p;
 
  if (!bmap) {
    fprintf(out, "null basic map\n");
    return;
  }
 
  fprintf(out, "%*s", indent, "");
  fprintf(out, "ref: %d, nparam: %d, in: %d, out: %d, extra: %d, "
      "flags: %x, n_name: %d\n",
    bmap->ref,
    bmap->dim->nparam, bmap->dim->n_in, bmap->dim->n_out,
    bmap->extra, bmap->flags, bmap->dim->n_id);
 
  p = isl_printer_to_file(isl_basic_map_get_ctx(bmap), out);
  p = isl_printer_set_dump(p, 1);
  p = isl_printer_set_indent(p, indent);
  p = isl_printer_start_line(p);
  p = isl_printer_print_basic_map(p, bmap);
  p = isl_printer_end_line(p);
  isl_printer_free(p);
}
 
__isl_give isl_basic_map *isl_inequality_negate(__isl_take isl_basic_map *bmap,
  unsigned pos)
{
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  if (pos >= bmap->n_ineq)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "invalid position", return isl_basic_map_free(bmap));
  isl_seq_neg(bmap->ineq[pos], bmap->ineq[pos], 1 + total);
  isl_int_sub_ui(bmap->ineq[pos][0], bmap->ineq[pos][0], 1);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NO_REDUNDANT);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  return bmap;
}
 
__isl_give isl_set *isl_set_alloc_space(__isl_take isl_space *space, int n,
  unsigned flags)
{
  if (isl_space_check_is_set(space) < 0)
    goto error;
  return isl_map_alloc_space(space, n, flags);
error:
  isl_space_free(space);
  return NULL;
}
 
/* Make sure "map" has room for at least "n" more basic maps.
 */
__isl_give isl_map *isl_map_grow(__isl_take isl_map *map, int n)
{
  int i;
  struct isl_map *grown = NULL;
 
  if (!map)
    return NULL;
  isl_assert(map->ctx, n >= 0, goto error);
  if (map->n + n <= map->size)
    return map;
  grown = isl_map_alloc_space(isl_map_get_space(map), map->n + n, map->flags);
  if (!grown)
    goto error;
  for (i = 0; i < map->n; ++i) {
    grown->p[i] = isl_basic_map_copy(map->p[i]);
    if (!grown->p[i])
      goto error;
    grown->n++;
  }
  isl_map_free(map);
  return grown;
error:
  isl_map_free(grown);
  isl_map_free(map);
  return NULL;
}
 
/* Make sure "set" has room for at least "n" more basic sets.
 */
__isl_give isl_set *isl_set_grow(__isl_take isl_set *set, int n)
{
  return set_from_map(isl_map_grow(set_to_map(set), n));
}
 
__isl_give isl_set *isl_set_from_basic_set(__isl_take isl_basic_set *bset)
{
  return isl_map_from_basic_map(bset);
}
 
/* This function performs the same operation as isl_set_from_basic_set,
 * but is considered as a function on an isl_basic_set when exported.
 */
__isl_give isl_set *isl_basic_set_to_set(__isl_take isl_basic_set *bset)
{
  return isl_set_from_basic_set(bset);
}
 
__isl_give isl_map *isl_map_from_basic_map(__isl_take isl_basic_map *bmap)
{
  struct isl_map *map;
 
  if (!bmap)
    return NULL;
 
  map = isl_map_alloc_space(isl_space_copy(bmap->dim), 1, ISL_MAP_DISJOINT);
  return isl_map_add_basic_map(map, bmap);
}
 
__isl_give isl_set *isl_set_add_basic_set(__isl_take isl_set *set,
            __isl_take isl_basic_set *bset)
{
  return set_from_map(isl_map_add_basic_map(set_to_map(set),
            bset_to_bmap(bset)));
}
 
__isl_null isl_set *isl_set_free(__isl_take isl_set *set)
{
  return isl_map_free(set);
}
 
void isl_set_print_internal(__isl_keep isl_set *set, FILE *out, int indent)
{
  int i;
 
  if (!set) {
    fprintf(out, "null set\n");
    return;
  }
 
  fprintf(out, "%*s", indent, "");
  fprintf(out, "ref: %d, n: %d, nparam: %d, dim: %d, flags: %x\n",
      set->ref, set->n, set->dim->nparam, set->dim->n_out,
      set->flags);
  for (i = 0; i < set->n; ++i) {
    fprintf(out, "%*s", indent, "");
    fprintf(out, "basic set %d:\n", i);
    isl_basic_set_print_internal(set->p[i], out, indent+4);
  }
}
 
void isl_map_print_internal(__isl_keep isl_map *map, FILE *out, int indent)
{
  int i;
 
  if (!map) {
    fprintf(out, "null map\n");
    return;
  }
 
  fprintf(out, "%*s", indent, "");
  fprintf(out, "ref: %d, n: %d, nparam: %d, in: %d, out: %d, "
         "flags: %x, n_name: %d\n",
      map->ref, map->n, map->dim->nparam, map->dim->n_in,
      map->dim->n_out, map->flags, map->dim->n_id);
  for (i = 0; i < map->n; ++i) {
    fprintf(out, "%*s", indent, "");
    fprintf(out, "basic map %d:\n", i);
    isl_basic_map_print_internal(map->p[i], out, indent+4);
  }
}
 
/* Check that the space of "bset" is the same as that of the domain of "bmap".
 */
static isl_stat isl_basic_map_check_compatible_domain(
  __isl_keep isl_basic_map *bmap, __isl_keep isl_basic_set *bset)
{
  isl_bool ok;
 
  ok = isl_basic_map_compatible_domain(bmap, bset);
  if (ok < 0)
    return isl_stat_error;
  if (!ok)
    isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
      "incompatible spaces", return isl_stat_error);
 
  return isl_stat_ok;
}
 
__isl_give isl_basic_map *isl_basic_map_intersect_domain(
  __isl_take isl_basic_map *bmap, __isl_take isl_basic_set *bset)
{
  struct isl_basic_map *bmap_domain;
  isl_size dim;
 
  if (isl_basic_map_check_equal_params(bmap, bset_to_bmap(bset)) < 0)
    goto error;
 
  dim = isl_basic_set_dim(bset, isl_dim_set);
  if (dim < 0)
    goto error;
  if (dim != 0 &&
      isl_basic_map_check_compatible_domain(bmap, bset) < 0)
    goto error;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    goto error;
  bmap = isl_basic_map_extend(bmap,
      bset->n_div, bset->n_eq, bset->n_ineq);
  bmap_domain = isl_basic_map_from_domain(bset);
  bmap = add_constraints(bmap, bmap_domain, 0, 0);
 
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  isl_basic_set_free(bset);
  return NULL;
}
 
/* Check that the space of "bset" is the same as that of the range of "bmap".
 */
static isl_stat isl_basic_map_check_compatible_range(
  __isl_keep isl_basic_map *bmap, __isl_keep isl_basic_set *bset)
{
  isl_bool ok;
 
  ok = isl_basic_map_compatible_range(bmap, bset);
  if (ok < 0)
    return isl_stat_error;
  if (!ok)
    isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
      "incompatible spaces", return isl_stat_error);
 
  return isl_stat_ok;
}
 
__isl_give isl_basic_map *isl_basic_map_intersect_range(
  __isl_take isl_basic_map *bmap, __isl_take isl_basic_set *bset)
{
  struct isl_basic_map *bmap_range;
  isl_size dim;
 
  if (isl_basic_map_check_equal_params(bmap, bset_to_bmap(bset)) < 0)
    goto error;
 
  dim = isl_basic_set_dim(bset, isl_dim_set);
  if (dim < 0)
    goto error;
  if (dim != 0 && isl_basic_map_check_compatible_range(bmap, bset) < 0)
    goto error;
 
  if (isl_basic_set_plain_is_universe(bset)) {
    isl_basic_set_free(bset);
    return bmap;
  }
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    goto error;
  bmap = isl_basic_map_extend(bmap,
      bset->n_div, bset->n_eq, bset->n_ineq);
  bmap_range = bset_to_bmap(bset);
  bmap = add_constraints(bmap, bmap_range, 0, 0);
 
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  isl_basic_set_free(bset);
  return NULL;
}
 
isl_bool isl_basic_map_contains(__isl_keep isl_basic_map *bmap,
  __isl_keep isl_vec *vec)
{
  int i;
  isl_size total;
  isl_int s;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0 || !vec)
    return isl_bool_error;
 
  if (1 + total != vec->size)
    return isl_bool_false;
 
  isl_int_init(s);
 
  for (i = 0; i < bmap->n_eq; ++i) {
    isl_seq_inner_product(vec->el, bmap->eq[i], 1 + total, &s);
    if (!isl_int_is_zero(s)) {
      isl_int_clear(s);
      return isl_bool_false;
    }
  }
 
  for (i = 0; i < bmap->n_ineq; ++i) {
    isl_seq_inner_product(vec->el, bmap->ineq[i], 1 + total, &s);
    if (isl_int_is_neg(s)) {
      isl_int_clear(s);
      return isl_bool_false;
    }
  }
 
  isl_int_clear(s);
 
  return isl_bool_true;
}
 
isl_bool isl_basic_set_contains(__isl_keep isl_basic_set *bset,
  __isl_keep isl_vec *vec)
{
  return isl_basic_map_contains(bset_to_bmap(bset), vec);
}
 
__isl_give isl_basic_map *isl_basic_map_intersect(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  struct isl_vec *sample = NULL;
  isl_space *space1, *space2;
  isl_size dim1, dim2, nparam1, nparam2;
 
  if (isl_basic_map_check_equal_params(bmap1, bmap2) < 0)
    goto error;
  space1 = isl_basic_map_peek_space(bmap1);
  space2 = isl_basic_map_peek_space(bmap2);
  dim1 = isl_space_dim(space1, isl_dim_all);
  dim2 = isl_space_dim(space2, isl_dim_all);
  nparam1 = isl_space_dim(space1, isl_dim_param);
  nparam2 = isl_space_dim(space2, isl_dim_param);
  if (dim1 < 0 || dim2 < 0 || nparam1 < 0 || nparam2 < 0)
    goto error;
  if (dim1 == nparam1 && dim2 != nparam2)
    return isl_basic_map_intersect(bmap2, bmap1);
 
  if (dim2 != nparam2 &&
      isl_basic_map_check_equal_space(bmap1, bmap2) < 0)
    goto error;
 
  if (isl_basic_map_plain_is_empty(bmap1)) {
    isl_basic_map_free(bmap2);
    return bmap1;
  }
  if (isl_basic_map_plain_is_empty(bmap2)) {
    isl_basic_map_free(bmap1);
    return bmap2;
  }
 
  if (bmap1->sample &&
      isl_basic_map_contains(bmap1, bmap1->sample) > 0 &&
      isl_basic_map_contains(bmap2, bmap1->sample) > 0)
    sample = isl_vec_copy(bmap1->sample);
  else if (bmap2->sample &&
      isl_basic_map_contains(bmap1, bmap2->sample) > 0 &&
      isl_basic_map_contains(bmap2, bmap2->sample) > 0)
    sample = isl_vec_copy(bmap2->sample);
 
  bmap1 = isl_basic_map_cow(bmap1);
  if (!bmap1)
    goto error;
  bmap1 = isl_basic_map_extend(bmap1,
      bmap2->n_div, bmap2->n_eq, bmap2->n_ineq);
  bmap1 = add_constraints(bmap1, bmap2, 0, 0);
 
  if (!bmap1)
    isl_vec_free(sample);
  else if (sample) {
    isl_vec_free(bmap1->sample);
    bmap1->sample = sample;
  }
 
  bmap1 = isl_basic_map_simplify(bmap1);
  return isl_basic_map_finalize(bmap1);
error:
  if (sample)
    isl_vec_free(sample);
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_intersect(
  __isl_take isl_basic_set *bset1, __isl_take isl_basic_set *bset2)
{
  return bset_from_bmap(isl_basic_map_intersect(bset_to_bmap(bset1),
              bset_to_bmap(bset2)));
}
 
/* Intersect the parameter domain of "bmap" with "bset".
 *
 * isl_basic_map_intersect handles this as a special case.
 */
__isl_give isl_basic_map *isl_basic_map_intersect_params(
  __isl_take isl_basic_map *bmap, __isl_take isl_basic_set *bset)
{
  return isl_basic_map_intersect(bmap, bset);
}
 
__isl_give isl_basic_set *isl_basic_set_intersect_params(
  __isl_take isl_basic_set *bset1, __isl_take isl_basic_set *bset2)
{
  isl_basic_map *bmap;
 
  bmap = bset_to_bmap(bset1);
  bmap = isl_basic_map_intersect_params(bmap, bset2);
  return bset_from_bmap(bmap);
}
 
/* Does "map" consist of a single disjunct, without any local variables?
 */
static isl_bool is_convex_no_locals(__isl_keep isl_map *map)
{
  isl_size n_div;
 
  if (!map)
    return isl_bool_error;
  if (map->n != 1)
    return isl_bool_false;
  n_div = isl_basic_map_dim(map->p[0], isl_dim_div);
  if (n_div < 0)
    return isl_bool_error;
  if (n_div != 0)
    return isl_bool_false;
  return isl_bool_true;
}
 
/* Check that "map" consists of a single disjunct, without any local variables.
 */
static isl_stat check_convex_no_locals(__isl_keep isl_map *map)
{
  isl_bool ok;
 
  ok = is_convex_no_locals(map);
  if (ok < 0)
    return isl_stat_error;
  if (ok)
    return isl_stat_ok;
 
  isl_die(isl_map_get_ctx(map), isl_error_internal,
    "unexpectedly not convex or involving local variables",
    return isl_stat_error);
}
 
/* Special case of isl_map_intersect, where both map1 and map2
 * are convex, without any divs and such that either map1 or map2
 * contains a single constraint.  This constraint is then simply
 * added to the other map.
 */
static __isl_give isl_map *map_intersect_add_constraint(
  __isl_take isl_map *map1, __isl_take isl_map *map2)
{
  if (check_convex_no_locals(map1) < 0 ||
      check_convex_no_locals(map2) < 0)
    goto error;
 
  if (map2->p[0]->n_eq + map2->p[0]->n_ineq != 1)
    return isl_map_intersect(map2, map1);
 
  map1 = isl_map_cow(map1);
  if (!map1)
    goto error;
  if (isl_map_plain_is_empty(map1)) {
    isl_map_free(map2);
    return map1;
  }
  if (map2->p[0]->n_eq == 1)
    map1->p[0] = isl_basic_map_add_eq(map1->p[0], map2->p[0]->eq[0]);
  else
    map1->p[0] = isl_basic_map_add_ineq(map1->p[0],
              map2->p[0]->ineq[0]);
 
  map1->p[0] = isl_basic_map_simplify(map1->p[0]);
  map1->p[0] = isl_basic_map_finalize(map1->p[0]);
  if (!map1->p[0])
    goto error;
 
  if (isl_basic_map_plain_is_empty(map1->p[0])) {
    isl_basic_map_free(map1->p[0]);
    map1->n = 0;
  }
 
  isl_map_free(map2);
 
  map1 = isl_map_unmark_normalized(map1);
  return map1;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
/* map2 may be either a parameter domain or a map living in the same
 * space as map1.
 */
static __isl_give isl_map *map_intersect_internal(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  unsigned flags = 0;
  isl_bool equal;
  isl_map *result;
  int i, j;
  isl_size dim2, nparam2;
 
  if (!map1 || !map2)
    goto error;
 
  if ((isl_map_plain_is_empty(map1) ||
       isl_map_plain_is_universe(map2)) &&
      isl_space_is_equal(map1->dim, map2->dim)) {
    isl_map_free(map2);
    return map1;
  }
  if ((isl_map_plain_is_empty(map2) ||
       isl_map_plain_is_universe(map1)) &&
      isl_space_is_equal(map1->dim, map2->dim)) {
    isl_map_free(map1);
    return map2;
  }
 
  if (is_convex_no_locals(map1) == isl_bool_true &&
      is_convex_no_locals(map2) == isl_bool_true &&
      isl_space_is_equal(map1->dim, map2->dim) &&
      (map1->p[0]->n_eq + map1->p[0]->n_ineq == 1 ||
       map2->p[0]->n_eq + map2->p[0]->n_ineq == 1))
    return map_intersect_add_constraint(map1, map2);
 
  equal = isl_map_plain_is_equal(map1, map2);
  if (equal < 0)
    goto error;
  if (equal) {
    isl_map_free(map2);
    return map1;
  }
 
  dim2 = isl_map_dim(map2, isl_dim_all);
  nparam2 = isl_map_dim(map2, isl_dim_param);
  if (dim2 < 0 || nparam2 < 0)
    goto error;
  if (dim2 != nparam2)
    isl_assert(map1->ctx,
          isl_space_is_equal(map1->dim, map2->dim), goto error);
 
  if (ISL_F_ISSET(map1, ISL_MAP_DISJOINT) &&
      ISL_F_ISSET(map2, ISL_MAP_DISJOINT))
    ISL_FL_SET(flags, ISL_MAP_DISJOINT);
 
  result = isl_map_alloc_space(isl_space_copy(map1->dim),
        map1->n * map2->n, flags);
  if (!result)
    goto error;
  for (i = 0; i < map1->n; ++i)
    for (j = 0; j < map2->n; ++j) {
      struct isl_basic_map *part;
      part = isl_basic_map_intersect(
            isl_basic_map_copy(map1->p[i]),
            isl_basic_map_copy(map2->p[j]));
      if (isl_basic_map_is_empty(part) < 0)
        part = isl_basic_map_free(part);
      result = isl_map_add_basic_map(result, part);
      if (!result)
        goto error;
    }
  isl_map_free(map1);
  isl_map_free(map2);
  return result;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
static __isl_give isl_map *map_intersect(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  if (isl_map_check_equal_space(map1, map2) < 0)
    goto error;
  return map_intersect_internal(map1, map2);
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
__isl_give isl_map *isl_map_intersect(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map_align_params_bin(&map1, &map2);
  return map_intersect(map1, map2);
}
 
__isl_give isl_set *isl_set_intersect(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  return set_from_map(isl_map_intersect(set_to_map(set1),
                set_to_map(set2)));
}
 
/* map_intersect_internal accepts intersections
 * with parameter domains, so we can just call that function.
 */
__isl_give isl_map *isl_map_intersect_params(__isl_take isl_map *map,
  __isl_take isl_set *params)
{
  isl_map_align_params_set(&map, &params);
  return map_intersect_internal(map, params);
}
 
__isl_give isl_set *isl_set_intersect_params(__isl_take isl_set *set,
    __isl_take isl_set *params)
{
  return isl_map_intersect_params(set, params);
}
 
__isl_give isl_basic_map *isl_basic_map_reverse(__isl_take isl_basic_map *bmap)
{
  isl_space *space;
  unsigned pos;
  isl_size n1, n2;
 
  if (!bmap)
    return NULL;
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
  space = isl_space_reverse(isl_space_copy(bmap->dim));
  pos = isl_basic_map_offset(bmap, isl_dim_in);
  n1 = isl_basic_map_dim(bmap, isl_dim_in);
  n2 = isl_basic_map_dim(bmap, isl_dim_out);
  if (n1 < 0 || n2 < 0)
    bmap = isl_basic_map_free(bmap);
  bmap = isl_basic_map_swap_vars(bmap, pos, n1, n2);
  return isl_basic_map_reset_space(bmap, space);
}
 
/* Given a basic map where the tuple of type "type" is a wrapped map,
 * swap domain and range of that wrapped map.
 */
static __isl_give isl_basic_map *isl_basic_map_reverse_wrapped(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type)
{
  isl_space *space;
  isl_size offset, n1, n2;
 
  space = isl_basic_map_peek_space(bmap);
  offset = isl_basic_map_var_offset(bmap, type);
  n1 = isl_space_wrapped_dim(space, type, isl_dim_in);
  n2 = isl_space_wrapped_dim(space, type, isl_dim_out);
  if (offset < 0 || n1 < 0 || n2 < 0)
    return isl_basic_map_free(bmap);
 
  bmap = isl_basic_map_swap_vars(bmap, 1 + offset, n1, n2);
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_reverse_wrapped(space, type);
  bmap = isl_basic_map_restore_space(bmap, space);
 
  return bmap;
}
 
/* Given a basic map (A -> B) -> C, return the corresponding basic map
 * (B -> A) -> C.
 */
static __isl_give isl_basic_map *isl_basic_map_domain_reverse(
  __isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_peek_space(bmap);
  if (isl_space_check_domain_is_wrapping(space) < 0)
    return isl_basic_map_free(bmap);
  bmap = isl_basic_map_reverse_wrapped(bmap, isl_dim_in);
 
  return bmap;
}
 
/* Given a basic map A -> (B -> C), return the corresponding basic map
 * A -> (C -> B).
 */
static __isl_give isl_basic_map *isl_basic_map_range_reverse(
  __isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_peek_space(bmap);
  if (isl_space_check_range_is_wrapping(space) < 0)
    return isl_basic_map_free(bmap);
  bmap = isl_basic_map_reverse_wrapped(bmap, isl_dim_out);
 
  return bmap;
}
 
/* Given a basic map that is actually a basic set (A -> B),
 * return the corresponding basic set (B -> A) as a basic map.
 */
static __isl_give isl_basic_map *isl_basic_map_set_reverse(
  __isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_peek_space(bmap);
  if (isl_space_check_is_wrapping(space) < 0)
    return isl_basic_map_free(bmap);
  bmap = isl_basic_map_reverse_wrapped(bmap, isl_dim_set);
 
  return bmap;
}
 
static __isl_give isl_basic_map *basic_map_space_reset(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type)
{
  isl_space *space;
 
  if (!bmap)
    return NULL;
  if (!isl_space_is_named_or_nested(bmap->dim, type))
    return bmap;
 
  space = isl_basic_map_get_space(bmap);
  space = isl_space_reset(space, type);
  bmap = isl_basic_map_reset_space(bmap, space);
  return bmap;
}
 
__isl_give isl_basic_map *isl_basic_map_insert_dims(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type,
  unsigned pos, unsigned n)
{
  isl_bool rational, is_empty;
  isl_space *res_space;
  struct isl_basic_map *res;
  struct isl_dim_map *dim_map;
  isl_size total;
  unsigned off;
  enum isl_dim_type t;
 
  if (n == 0)
    return basic_map_space_reset(bmap, type);
 
  is_empty = isl_basic_map_plain_is_empty(bmap);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (is_empty < 0 || total < 0)
    return isl_basic_map_free(bmap);
  res_space = isl_space_insert_dims(isl_basic_map_get_space(bmap),
          type, pos, n);
  if (!res_space)
    return isl_basic_map_free(bmap);
  if (is_empty) {
    isl_basic_map_free(bmap);
    return isl_basic_map_empty(res_space);
  }
 
  dim_map = isl_dim_map_alloc(bmap->ctx, total + n);
  off = 0;
  for (t = isl_dim_param; t <= isl_dim_out; ++t) {
    isl_size dim;
 
    if (t != type) {
      isl_dim_map_dim(dim_map, bmap->dim, t, off);
    } else {
      isl_size size = isl_basic_map_dim(bmap, t);
      if (size < 0)
        dim_map = isl_dim_map_free(dim_map);
      isl_dim_map_dim_range(dim_map, bmap->dim, t,
            0, pos, off);
      isl_dim_map_dim_range(dim_map, bmap->dim, t,
            pos, size - pos, off + pos + n);
    }
    dim = isl_space_dim(res_space, t);
    if (dim < 0)
      dim_map = isl_dim_map_free(dim_map);
    off += dim;
  }
  isl_dim_map_div(dim_map, bmap, off);
 
  res = isl_basic_map_alloc_space(res_space,
      bmap->n_div, bmap->n_eq, bmap->n_ineq);
  rational = isl_basic_map_is_rational(bmap);
  if (rational < 0)
    res = isl_basic_map_free(res);
  if (rational)
    res = isl_basic_map_set_rational(res);
  res = isl_basic_map_add_constraints_dim_map(res, bmap, dim_map);
  return isl_basic_map_finalize(res);
}
 
__isl_give isl_basic_set *isl_basic_set_insert_dims(
  __isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned pos, unsigned n)
{
  return isl_basic_map_insert_dims(bset, type, pos, n);
}
 
__isl_give isl_basic_map *isl_basic_map_add_dims(__isl_take isl_basic_map *bmap,
    enum isl_dim_type type, unsigned n)
{
  isl_size dim;
 
  dim = isl_basic_map_dim(bmap, type);
  if (dim < 0)
    return isl_basic_map_free(bmap);
  return isl_basic_map_insert_dims(bmap, type, dim, n);
}
 
__isl_give isl_basic_set *isl_basic_set_add_dims(__isl_take isl_basic_set *bset,
    enum isl_dim_type type, unsigned n)
{
  if (!bset)
    return NULL;
  isl_assert(bset->ctx, type != isl_dim_in, goto error);
  return isl_basic_map_add_dims(bset, type, n);
error:
  isl_basic_set_free(bset);
  return NULL;
}
 
static __isl_give isl_map *map_space_reset(__isl_take isl_map *map,
  enum isl_dim_type type)
{
  isl_space *space;
 
  if (!map || !isl_space_is_named_or_nested(map->dim, type))
    return map;
 
  space = isl_map_get_space(map);
  space = isl_space_reset(space, type);
  map = isl_map_reset_space(map, space);
  return map;
}
 
__isl_give isl_map *isl_map_insert_dims(__isl_take isl_map *map,
    enum isl_dim_type type, unsigned pos, unsigned n)
{
  int i;
  isl_space *space;
 
  if (n == 0)
    return map_space_reset(map, type);
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_insert_dims(map->p[i], type, pos, n);
    if (!map->p[i])
      goto error;
  }
 
  space = isl_map_take_space(map);
  space = isl_space_insert_dims(space, type, pos, n);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_insert_dims(__isl_take isl_set *set,
    enum isl_dim_type type, unsigned pos, unsigned n)
{
  return isl_map_insert_dims(set, type, pos, n);
}
 
__isl_give isl_map *isl_map_add_dims(__isl_take isl_map *map,
    enum isl_dim_type type, unsigned n)
{
  isl_size dim;
 
  dim = isl_map_dim(map, type);
  if (dim < 0)
    return isl_map_free(map);
  return isl_map_insert_dims(map, type, dim, n);
}
 
__isl_give isl_set *isl_set_add_dims(__isl_take isl_set *set,
    enum isl_dim_type type, unsigned n)
{
  if (!set)
    return NULL;
  isl_assert(set->ctx, type != isl_dim_in, goto error);
  return set_from_map(isl_map_add_dims(set_to_map(set), type, n));
error:
  isl_set_free(set);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_move_dims(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type dst_type, unsigned dst_pos,
  enum isl_dim_type src_type, unsigned src_pos, unsigned n)
{
  isl_space *space;
  struct isl_dim_map *dim_map;
  struct isl_basic_map *res;
  enum isl_dim_type t;
  isl_size total;
  unsigned off;
 
  if (!bmap)
    return NULL;
  if (n == 0) {
    bmap = isl_basic_map_reset(bmap, src_type);
    bmap = isl_basic_map_reset(bmap, dst_type);
    return bmap;
  }
 
  if (isl_basic_map_check_range(bmap, src_type, src_pos, n) < 0)
    return isl_basic_map_free(bmap);
 
  if (dst_type == src_type && dst_pos == src_pos)
    return bmap;
 
  isl_assert(bmap->ctx, dst_type != src_type, goto error);
 
  if (pos(bmap->dim, dst_type) + dst_pos ==
      pos(bmap->dim, src_type) + src_pos +
              ((src_type < dst_type) ? n : 0)) {
    space = isl_basic_map_take_space(bmap);
    space = isl_space_move_dims(space, dst_type, dst_pos,
            src_type, src_pos, n);
    bmap = isl_basic_map_restore_space(bmap, space);
    bmap = isl_basic_map_finalize(bmap);
 
    return bmap;
  }
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  dim_map = isl_dim_map_alloc(bmap->ctx, total);
 
  off = 0;
  space = isl_basic_map_peek_space(bmap);
  for (t = isl_dim_param; t <= isl_dim_out; ++t) {
    isl_size size = isl_space_dim(space, t);
    if (size < 0)
      dim_map = isl_dim_map_free(dim_map);
    if (t == dst_type) {
      isl_dim_map_dim_range(dim_map, space, t,
              0, dst_pos, off);
      off += dst_pos;
      isl_dim_map_dim_range(dim_map, space, src_type,
              src_pos, n, off);
      off += n;
      isl_dim_map_dim_range(dim_map, space, t,
              dst_pos, size - dst_pos, off);
      off += size - dst_pos;
    } else if (t == src_type) {
      isl_dim_map_dim_range(dim_map, space, t,
              0, src_pos, off);
      off += src_pos;
      isl_dim_map_dim_range(dim_map, space, t,
          src_pos + n, size - src_pos - n, off);
      off += size - src_pos - n;
    } else {
      isl_dim_map_dim(dim_map, space, t, off);
      off += size;
    }
  }
  isl_dim_map_div(dim_map, bmap, off);
 
  res = isl_basic_map_alloc_space(isl_basic_map_get_space(bmap),
      bmap->n_div, bmap->n_eq, bmap->n_ineq);
  bmap = isl_basic_map_add_constraints_dim_map(res, bmap, dim_map);
  space = isl_basic_map_take_space(bmap);
  space = isl_space_move_dims(space, dst_type, dst_pos,
          src_type, src_pos, n);
  bmap = isl_basic_map_restore_space(bmap, space);
  if (!bmap)
    goto error;
 
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  bmap = isl_basic_map_gauss(bmap, NULL);
  bmap = isl_basic_map_finalize(bmap);
 
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_move_dims(__isl_take isl_basic_set *bset,
  enum isl_dim_type dst_type, unsigned dst_pos,
  enum isl_dim_type src_type, unsigned src_pos, unsigned n)
{
  isl_basic_map *bmap = bset_to_bmap(bset);
  bmap = isl_basic_map_move_dims(bmap, dst_type, dst_pos,
          src_type, src_pos, n);
  return bset_from_bmap(bmap);
}
 
__isl_give isl_set *isl_set_move_dims(__isl_take isl_set *set,
  enum isl_dim_type dst_type, unsigned dst_pos,
  enum isl_dim_type src_type, unsigned src_pos, unsigned n)
{
  if (!set)
    return NULL;
  isl_assert(set->ctx, dst_type != isl_dim_in, goto error);
  return set_from_map(isl_map_move_dims(set_to_map(set),
            dst_type, dst_pos, src_type, src_pos, n));
error:
  isl_set_free(set);
  return NULL;
}
 
__isl_give isl_map *isl_map_move_dims(__isl_take isl_map *map,
  enum isl_dim_type dst_type, unsigned dst_pos,
  enum isl_dim_type src_type, unsigned src_pos, unsigned n)
{
  int i;
  isl_space *space;
 
  if (n == 0) {
    map = isl_map_reset(map, src_type);
    map = isl_map_reset(map, dst_type);
    return map;
  }
 
  if (isl_map_check_range(map, src_type, src_pos, n))
    return isl_map_free(map);
 
  if (dst_type == src_type && dst_pos == src_pos)
    return map;
 
  isl_assert(map->ctx, dst_type != src_type, goto error);
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_move_dims(map->p[i],
            dst_type, dst_pos,
            src_type, src_pos, n);
    if (!map->p[i])
      goto error;
  }
 
  space = isl_map_take_space(map);
  space = isl_space_move_dims(space, dst_type, dst_pos,
              src_type, src_pos, n);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
/* Move the specified dimensions to the last columns right before
 * the divs.  Don't change the dimension specification of bmap.
 * That's the responsibility of the caller.
 */
static __isl_give isl_basic_map *move_last(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  isl_space *space;
  struct isl_dim_map *dim_map;
  struct isl_basic_map *res;
  enum isl_dim_type t;
  isl_size total;
  unsigned off;
 
  if (!bmap)
    return NULL;
  if (isl_basic_map_offset(bmap, type) + first + n ==
        isl_basic_map_offset(bmap, isl_dim_div))
    return bmap;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  dim_map = isl_dim_map_alloc(bmap->ctx, total);
 
  off = 0;
  space = isl_basic_map_peek_space(bmap);
  for (t = isl_dim_param; t <= isl_dim_out; ++t) {
    isl_size size = isl_space_dim(space, t);
    if (size < 0)
      dim_map = isl_dim_map_free(dim_map);
    if (t == type) {
      isl_dim_map_dim_range(dim_map, space, t,
              0, first, off);
      off += first;
      isl_dim_map_dim_range(dim_map, space, t,
              first, n, total - bmap->n_div - n);
      isl_dim_map_dim_range(dim_map, space, t,
              first + n, size - (first + n), off);
      off += size - (first + n);
    } else {
      isl_dim_map_dim(dim_map, space, t, off);
      off += size;
    }
  }
  isl_dim_map_div(dim_map, bmap, off + n);
 
  res = isl_basic_map_alloc_space(isl_basic_map_get_space(bmap),
      bmap->n_div, bmap->n_eq, bmap->n_ineq);
  res = isl_basic_map_add_constraints_dim_map(res, bmap, dim_map);
  return res;
}
 
/* Insert "n" rows in the divs of "bmap".
 *
 * The number of columns is not changed, which means that the last
 * dimensions of "bmap" are being reintepreted as the new divs.
 * The space of "bmap" is not adjusted, however, which means
 * that "bmap" is left in an inconsistent state.  Removing "n" dimensions
 * from the space of "bmap" is the responsibility of the caller.
 */
static __isl_give isl_basic_map *insert_div_rows(__isl_take isl_basic_map *bmap,
  int n)
{
  int i;
  size_t row_size;
  isl_int **new_div;
  isl_int *old;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
 
  row_size = isl_basic_map_offset(bmap, isl_dim_div) + bmap->extra;
  old = bmap->block2.data;
  bmap->block2 = isl_blk_extend(bmap->ctx, bmap->block2,
          (bmap->extra + n) * (1 + row_size));
  if (!bmap->block2.data)
    return isl_basic_map_free(bmap);
  new_div = isl_alloc_array(bmap->ctx, isl_int *, bmap->extra + n);
  if (!new_div)
    return isl_basic_map_free(bmap);
  for (i = 0; i < n; ++i) {
    new_div[i] = bmap->block2.data +
        (bmap->extra + i) * (1 + row_size);
    isl_seq_clr(new_div[i], 1 + row_size);
  }
  for (i = 0; i < bmap->extra; ++i)
    new_div[n + i] = bmap->block2.data + (bmap->div[i] - old);
  free(bmap->div);
  bmap->div = new_div;
  bmap->n_div += n;
  bmap->extra += n;
 
  return bmap;
}
 
/* Drop constraints from "bmap" that only involve the variables
 * of "type" in the range [first, first + n] that are not related
 * to any of the variables outside that interval.
 * These constraints cannot influence the values for the variables
 * outside the interval, except in case they cause "bmap" to be empty.
 * Only drop the constraints if "bmap" is known to be non-empty.
 */
static __isl_give isl_basic_map *drop_irrelevant_constraints(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type,
  unsigned first, unsigned n)
{
  int i;
  int *groups;
  isl_size dim, n_div;
  isl_bool non_empty;
 
  non_empty = isl_basic_map_plain_is_non_empty(bmap);
  if (non_empty < 0)
    return isl_basic_map_free(bmap);
  if (!non_empty)
    return bmap;
 
  dim = isl_basic_map_dim(bmap, isl_dim_all);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (dim < 0 || n_div < 0)
    return isl_basic_map_free(bmap);
  groups = isl_calloc_array(isl_basic_map_get_ctx(bmap), int, dim);
  if (!groups)
    return isl_basic_map_free(bmap);
  first += isl_basic_map_offset(bmap, type) - 1;
  for (i = 0; i < first; ++i)
    groups[i] = -1;
  for (i = first + n; i < dim - n_div; ++i)
    groups[i] = -1;
 
  bmap = isl_basic_map_drop_unrelated_constraints(bmap, groups);
 
  return bmap;
}
 
/* Turn the n dimensions of type type, starting at first
 * into existentially quantified variables.
 *
 * If a subset of the projected out variables are unrelated
 * to any of the variables that remain, then the constraints
 * involving this subset are simply dropped first.
 */
__isl_give isl_basic_map *isl_basic_map_project_out(
    __isl_take isl_basic_map *bmap,
    enum isl_dim_type type, unsigned first, unsigned n)
{
  isl_bool empty;
  isl_space *space;
 
  if (n == 0)
    return basic_map_space_reset(bmap, type);
  if (type == isl_dim_div)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "cannot project out existentially quantified variables",
      return isl_basic_map_free(bmap));
 
  empty = isl_basic_map_plain_is_empty(bmap);
  if (empty < 0)
    return isl_basic_map_free(bmap);
  if (empty)
    bmap = isl_basic_map_set_to_empty(bmap);
 
  bmap = drop_irrelevant_constraints(bmap, type, first, n);
  if (!bmap)
    return NULL;
 
  if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
    return isl_basic_map_remove_dims(bmap, type, first, n);
 
  if (isl_basic_map_check_range(bmap, type, first, n) < 0)
    return isl_basic_map_free(bmap);
 
  bmap = move_last(bmap, type, first, n);
  bmap = isl_basic_map_cow(bmap);
  bmap = insert_div_rows(bmap, n);
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_drop_dims(space, type, first, n);
  bmap = isl_basic_map_restore_space(bmap, space);
  bmap = isl_basic_map_simplify(bmap);
  bmap = isl_basic_map_drop_redundant_divs(bmap);
  return isl_basic_map_finalize(bmap);
}
 
/* Turn the n dimensions of type type, starting at first
 * into existentially quantified variables.
 */
__isl_give isl_basic_set *isl_basic_set_project_out(
  __isl_take isl_basic_set *bset, enum isl_dim_type type,
  unsigned first, unsigned n)
{
  return bset_from_bmap(isl_basic_map_project_out(bset_to_bmap(bset),
              type, first, n));
}
 
/* Turn the n dimensions of type type, starting at first
 * into existentially quantified variables.
 */
__isl_give isl_map *isl_map_project_out(__isl_take isl_map *map,
    enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
  isl_space *space;
 
  if (n == 0)
    return map_space_reset(map, type);
 
  if (isl_map_check_range(map, type, first, n) < 0)
    return isl_map_free(map);
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_project_out(map->p[i], type, first, n);
    if (!map->p[i])
      goto error;
  }
 
  if (map->n > 1)
    ISL_F_CLR(map, ISL_MAP_DISJOINT);
  map = isl_map_unmark_normalized(map);
 
  space = isl_map_take_space(map);
  space = isl_space_drop_dims(space, type, first, n);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
#undef TYPE
#define TYPE  isl_map
#include "isl_project_out_all_params_templ.c"
#include "isl_project_out_param_templ.c"
 
/* Turn all the dimensions of type "type", except the "n" starting at "first"
 * into existentially quantified variables.
 */
__isl_give isl_map *isl_map_project_onto(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  isl_size dim;
 
  dim = isl_map_dim(map, type);
  if (isl_map_check_range(map, type, first, n) < 0 || dim < 0)
    return isl_map_free(map);
  map = isl_map_project_out(map, type, first + n, dim - (first + n));
  map = isl_map_project_out(map, type, 0, first);
  return map;
}
 
/* Turn the n dimensions of type type, starting at first
 * into existentially quantified variables.
 */
__isl_give isl_set *isl_set_project_out(__isl_take isl_set *set,
    enum isl_dim_type type, unsigned first, unsigned n)
{
  return set_from_map(isl_map_project_out(set_to_map(set),
            type, first, n));
}
 
/* If "set" involves a parameter with identifier "id",
 * then turn it into an existentially quantified variable.
 */
__isl_give isl_set *isl_set_project_out_param_id(__isl_take isl_set *set,
  __isl_take isl_id *id)
{
  return set_from_map(isl_map_project_out_param_id(set_to_map(set), id));
}
 
/* If "set" involves any of the parameters with identifiers in "list",
 * then turn them into existentially quantified variables.
 */
__isl_give isl_set *isl_set_project_out_param_id_list(__isl_take isl_set *set,
  __isl_take isl_id_list *list)
{
  isl_map *map;
 
  map = set_to_map(set);
  map = isl_map_project_out_param_id_list(map, list);
  return set_from_map(map);
}
 
/* Project out all parameters from "set" by existentially quantifying
 * over them.
 */
__isl_give isl_set *isl_set_project_out_all_params(__isl_take isl_set *set)
{
  return set_from_map(isl_map_project_out_all_params(set_to_map(set)));
}
 
/* Return a map that projects the elements in "set" onto their
 * "n" set dimensions starting at "first".
 * "type" should be equal to isl_dim_set.
 */
__isl_give isl_map *isl_set_project_onto_map(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
  isl_map *map;
 
  if (type != isl_dim_set)
    isl_die(isl_set_get_ctx(set), isl_error_invalid,
      "only set dimensions can be projected out", goto error);
  if (isl_set_check_range(set, type, first, n) < 0)
    return isl_set_free(set);
 
  map = isl_map_from_domain(set);
  map = isl_map_add_dims(map, isl_dim_out, n);
  for (i = 0; i < n; ++i)
    map = isl_map_equate(map, isl_dim_in, first + i,
          isl_dim_out, i);
  return map;
error:
  isl_set_free(set);
  return NULL;
}
 
static __isl_give isl_basic_map *add_divs(__isl_take isl_basic_map *bmap,
  unsigned n)
{
  int i, j;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  for (i = 0; i < n; ++i) {
    j = isl_basic_map_alloc_div(bmap);
    if (j < 0)
      goto error;
    isl_seq_clr(bmap->div[j], 1 + 1 + total);
  }
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Does "bmap2" apply to the range of "bmap1" (ignoring parameters)?
 */
isl_bool isl_basic_map_applies_range(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  isl_space *space1, *space2;
 
  space1 = isl_basic_map_peek_space(bmap1);
  space2 = isl_basic_map_peek_space(bmap2);
  return isl_space_tuple_is_equal(space1, isl_dim_out,
          space2, isl_dim_in);
}
 
/* Check that "bmap2" applies to the range of "bmap1" (ignoring parameters).
 */
static isl_stat isl_basic_map_check_applies_range(
  __isl_keep isl_basic_map *bmap1, __isl_keep isl_basic_map *bmap2)
{
  isl_bool equal;
 
  equal = isl_basic_map_applies_range(bmap1, bmap2);
  if (equal < 0)
    return isl_stat_error;
  if (!equal)
    isl_die(isl_basic_map_get_ctx(bmap1), isl_error_invalid,
      "spaces don't match", return isl_stat_error);
  return isl_stat_ok;
}
 
__isl_give isl_basic_map *isl_basic_map_apply_range(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  isl_space *space_result = NULL;
  struct isl_basic_map *bmap;
  isl_size n_in, n_out, n, nparam;
  unsigned total, pos;
  struct isl_dim_map *dim_map1, *dim_map2;
 
  if (isl_basic_map_check_equal_params(bmap1, bmap2) < 0)
    goto error;
  if (isl_basic_map_check_applies_range(bmap1, bmap2) < 0)
    goto error;
 
  n_in = isl_basic_map_dim(bmap1, isl_dim_in);
  n_out = isl_basic_map_dim(bmap2, isl_dim_out);
  n = isl_basic_map_dim(bmap1, isl_dim_out);
  nparam = isl_basic_map_dim(bmap1, isl_dim_param);
  if (n_in < 0 || n_out < 0 || n < 0 || nparam < 0)
    goto error;
 
  space_result = isl_space_join(isl_basic_map_get_space(bmap1),
          isl_basic_map_get_space(bmap2));
 
  total = nparam + n_in + n_out + bmap1->n_div + bmap2->n_div + n;
  dim_map1 = isl_dim_map_alloc(bmap1->ctx, total);
  dim_map2 = isl_dim_map_alloc(bmap1->ctx, total);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_in, pos += nparam);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_out, pos += n_in);
  isl_dim_map_div(dim_map1, bmap1, pos += n_out);
  isl_dim_map_div(dim_map2, bmap2, pos += bmap1->n_div);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_out, pos += bmap2->n_div);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_in, pos);
 
  bmap = isl_basic_map_alloc_space(space_result,
      bmap1->n_div + bmap2->n_div + n,
      bmap1->n_eq + bmap2->n_eq,
      bmap1->n_ineq + bmap2->n_ineq);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap1, dim_map1);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap2, dim_map2);
  bmap = add_divs(bmap, n);
  bmap = isl_basic_map_simplify(bmap);
  bmap = isl_basic_map_drop_redundant_divs(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_apply(__isl_take isl_basic_set *bset,
  __isl_take isl_basic_map *bmap)
{
  if (isl_basic_map_check_compatible_domain(bmap, bset) < 0)
    goto error;
 
  return bset_from_bmap(isl_basic_map_apply_range(bset_to_bmap(bset),
              bmap));
error:
  isl_basic_set_free(bset);
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_apply_domain(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  if (isl_basic_map_check_equal_params(bmap1, bmap2) < 0)
    goto error;
  if (!isl_space_tuple_is_equal(bmap1->dim, isl_dim_in,
          bmap2->dim, isl_dim_in))
    isl_die(isl_basic_map_get_ctx(bmap1), isl_error_invalid,
      "spaces don't match", goto error);
 
  bmap1 = isl_basic_map_reverse(bmap1);
  bmap1 = isl_basic_map_apply_range(bmap1, bmap2);
  return isl_basic_map_reverse(bmap1);
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
/* Given two basic maps A -> f(A) and B -> g(B), construct a basic map
 * A \cap B -> f(A) + f(B)
 */
__isl_give isl_basic_map *isl_basic_map_sum(__isl_take isl_basic_map *bmap1,
  __isl_take isl_basic_map *bmap2)
{
  isl_size n_in, n_out, nparam;
  unsigned total, pos;
  struct isl_basic_map *bmap = NULL;
  struct isl_dim_map *dim_map1, *dim_map2;
  int i;
 
  if (isl_basic_map_check_equal_space(bmap1, bmap2) < 0)
    goto error;
 
  nparam = isl_basic_map_dim(bmap1, isl_dim_param);
  n_in = isl_basic_map_dim(bmap1, isl_dim_in);
  n_out = isl_basic_map_dim(bmap1, isl_dim_out);
  if (nparam < 0 || n_in < 0 || n_out < 0)
    goto error;
 
  total = nparam + n_in + n_out + bmap1->n_div + bmap2->n_div + 2 * n_out;
  dim_map1 = isl_dim_map_alloc(bmap1->ctx, total);
  dim_map2 = isl_dim_map_alloc(bmap2->ctx, total);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_param, pos);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_in, pos += nparam);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_in, pos);
  isl_dim_map_div(dim_map1, bmap1, pos += n_in + n_out);
  isl_dim_map_div(dim_map2, bmap2, pos += bmap1->n_div);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_out, pos += bmap2->n_div);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_out, pos += n_out);
 
  bmap = isl_basic_map_alloc_space(isl_space_copy(bmap1->dim),
      bmap1->n_div + bmap2->n_div + 2 * n_out,
      bmap1->n_eq + bmap2->n_eq + n_out,
      bmap1->n_ineq + bmap2->n_ineq);
  for (i = 0; i < n_out; ++i) {
    int j = isl_basic_map_alloc_equality(bmap);
    if (j < 0)
      goto error;
    isl_seq_clr(bmap->eq[j], 1+total);
    isl_int_set_si(bmap->eq[j][1+nparam+n_in+i], -1);
    isl_int_set_si(bmap->eq[j][1+pos+i], 1);
    isl_int_set_si(bmap->eq[j][1+pos-n_out+i], 1);
  }
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap1, dim_map1);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap2, dim_map2);
  bmap = add_divs(bmap, 2 * n_out);
 
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
/* Given two maps A -> f(A) and B -> g(B), construct a map
 * A \cap B -> f(A) + f(B)
 */
__isl_give isl_map *isl_map_sum(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  struct isl_map *result;
  int i, j;
 
  if (isl_map_check_equal_space(map1, map2) < 0)
    goto error;
 
  result = isl_map_alloc_space(isl_space_copy(map1->dim),
        map1->n * map2->n, 0);
  if (!result)
    goto error;
  for (i = 0; i < map1->n; ++i)
    for (j = 0; j < map2->n; ++j) {
      struct isl_basic_map *part;
      part = isl_basic_map_sum(
            isl_basic_map_copy(map1->p[i]),
            isl_basic_map_copy(map2->p[j]));
      if (isl_basic_map_is_empty(part))
        isl_basic_map_free(part);
      else
        result = isl_map_add_basic_map(result, part);
      if (!result)
        goto error;
    }
  isl_map_free(map1);
  isl_map_free(map2);
  return result;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
__isl_give isl_set *isl_set_sum(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  return set_from_map(isl_map_sum(set_to_map(set1), set_to_map(set2)));
}
 
/* Given a basic map A -> f(A), construct A -> -f(A).
 */
__isl_give isl_basic_map *isl_basic_map_neg(__isl_take isl_basic_map *bmap)
{
  int i, j;
  unsigned off;
  isl_size n;
 
  bmap = isl_basic_map_cow(bmap);
  n = isl_basic_map_dim(bmap, isl_dim_out);
  if (n < 0)
    return isl_basic_map_free(bmap);
 
  off = isl_basic_map_offset(bmap, isl_dim_out);
  for (i = 0; i < bmap->n_eq; ++i)
    for (j = 0; j < n; ++j)
      isl_int_neg(bmap->eq[i][off+j], bmap->eq[i][off+j]);
  for (i = 0; i < bmap->n_ineq; ++i)
    for (j = 0; j < n; ++j)
      isl_int_neg(bmap->ineq[i][off+j], bmap->ineq[i][off+j]);
  for (i = 0; i < bmap->n_div; ++i)
    for (j = 0; j < n; ++j)
      isl_int_neg(bmap->div[i][1+off+j], bmap->div[i][1+off+j]);
  bmap = isl_basic_map_gauss(bmap, NULL);
  return isl_basic_map_finalize(bmap);
}
 
__isl_give isl_basic_set *isl_basic_set_neg(__isl_take isl_basic_set *bset)
{
  return isl_basic_map_neg(bset);
}
 
/* Given a map A -> f(A), construct A -> -f(A).
 */
__isl_give isl_map *isl_map_neg(__isl_take isl_map *map)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_neg(map->p[i]);
    if (!map->p[i])
      goto error;
  }
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_neg(__isl_take isl_set *set)
{
  return set_from_map(isl_map_neg(set_to_map(set)));
}
 
/* Given a basic map A -> f(A) and an integer d, construct a basic map
 * A -> floor(f(A)/d).
 */
__isl_give isl_basic_map *isl_basic_map_floordiv(__isl_take isl_basic_map *bmap,
    isl_int d)
{
  isl_size n_in, n_out, nparam;
  unsigned total, pos;
  struct isl_basic_map *result = NULL;
  struct isl_dim_map *dim_map;
  int i;
 
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (nparam < 0 || n_in < 0 || n_out < 0)
    return isl_basic_map_free(bmap);
 
  total = nparam + n_in + n_out + bmap->n_div + n_out;
  dim_map = isl_dim_map_alloc(bmap->ctx, total);
  isl_dim_map_dim(dim_map, bmap->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map, bmap->dim, isl_dim_in, pos += nparam);
  isl_dim_map_div(dim_map, bmap, pos += n_in + n_out);
  isl_dim_map_dim(dim_map, bmap->dim, isl_dim_out, pos += bmap->n_div);
 
  result = isl_basic_map_alloc_space(isl_space_copy(bmap->dim),
      bmap->n_div + n_out,
      bmap->n_eq, bmap->n_ineq + 2 * n_out);
  result = isl_basic_map_add_constraints_dim_map(result, bmap, dim_map);
  result = add_divs(result, n_out);
  for (i = 0; i < n_out; ++i) {
    int j;
    j = isl_basic_map_alloc_inequality(result);
    if (j < 0)
      goto error;
    isl_seq_clr(result->ineq[j], 1+total);
    isl_int_neg(result->ineq[j][1+nparam+n_in+i], d);
    isl_int_set_si(result->ineq[j][1+pos+i], 1);
    j = isl_basic_map_alloc_inequality(result);
    if (j < 0)
      goto error;
    isl_seq_clr(result->ineq[j], 1+total);
    isl_int_set(result->ineq[j][1+nparam+n_in+i], d);
    isl_int_set_si(result->ineq[j][1+pos+i], -1);
    isl_int_sub_ui(result->ineq[j][0], d, 1);
  }
 
  result = isl_basic_map_simplify(result);
  return isl_basic_map_finalize(result);
error:
  isl_basic_map_free(result);
  return NULL;
}
 
/* Given a map A -> f(A) and an integer d, construct a map
 * A -> floor(f(A)/d).
 */
__isl_give isl_map *isl_map_floordiv(__isl_take isl_map *map, isl_int d)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  ISL_F_CLR(map, ISL_MAP_DISJOINT);
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_floordiv(map->p[i], d);
    if (!map->p[i])
      goto error;
  }
  map = isl_map_unmark_normalized(map);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
/* Given a map A -> f(A) and an integer d, construct a map
 * A -> floor(f(A)/d).
 */
__isl_give isl_map *isl_map_floordiv_val(__isl_take isl_map *map,
  __isl_take isl_val *d)
{
  if (!map || !d)
    goto error;
  if (!isl_val_is_int(d))
    isl_die(isl_val_get_ctx(d), isl_error_invalid,
      "expecting integer denominator", goto error);
  map = isl_map_floordiv(map, d->n);
  isl_val_free(d);
  return map;
error:
  isl_map_free(map);
  isl_val_free(d);
  return NULL;
}
 
static __isl_give isl_basic_map *var_equal(__isl_take isl_basic_map *bmap,
  unsigned pos)
{
  int i;
  isl_size nparam;
  isl_size n_in;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  if (total < 0 || nparam < 0 || n_in < 0)
    return isl_basic_map_free(bmap);
  i = isl_basic_map_alloc_equality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->eq[i], 1 + total);
  isl_int_set_si(bmap->eq[i][1+nparam+pos], -1);
  isl_int_set_si(bmap->eq[i][1+nparam+n_in+pos], 1);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Add a constraint to "bmap" expressing i_pos < o_pos
 */
static __isl_give isl_basic_map *var_less(__isl_take isl_basic_map *bmap,
  unsigned pos)
{
  int i;
  isl_size nparam;
  isl_size n_in;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  if (total < 0 || nparam < 0 || n_in < 0)
    return isl_basic_map_free(bmap);
  i = isl_basic_map_alloc_inequality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->ineq[i], 1 + total);
  isl_int_set_si(bmap->ineq[i][0], -1);
  isl_int_set_si(bmap->ineq[i][1+nparam+pos], -1);
  isl_int_set_si(bmap->ineq[i][1+nparam+n_in+pos], 1);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Add a constraint to "bmap" expressing i_pos <= o_pos
 */
static __isl_give isl_basic_map *var_less_or_equal(
  __isl_take isl_basic_map *bmap, unsigned pos)
{
  int i;
  isl_size nparam;
  isl_size n_in;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  if (total < 0 || nparam < 0 || n_in < 0)
    return isl_basic_map_free(bmap);
  i = isl_basic_map_alloc_inequality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->ineq[i], 1 + total);
  isl_int_set_si(bmap->ineq[i][1+nparam+pos], -1);
  isl_int_set_si(bmap->ineq[i][1+nparam+n_in+pos], 1);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Add a constraint to "bmap" expressing i_pos > o_pos
 */
static __isl_give isl_basic_map *var_more(__isl_take isl_basic_map *bmap,
  unsigned pos)
{
  int i;
  isl_size nparam;
  isl_size n_in;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  if (total < 0 || nparam < 0 || n_in < 0)
    return isl_basic_map_free(bmap);
  i = isl_basic_map_alloc_inequality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->ineq[i], 1 + total);
  isl_int_set_si(bmap->ineq[i][0], -1);
  isl_int_set_si(bmap->ineq[i][1+nparam+pos], 1);
  isl_int_set_si(bmap->ineq[i][1+nparam+n_in+pos], -1);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Add a constraint to "bmap" expressing i_pos >= o_pos
 */
static __isl_give isl_basic_map *var_more_or_equal(
  __isl_take isl_basic_map *bmap, unsigned pos)
{
  int i;
  isl_size nparam;
  isl_size n_in;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  if (total < 0 || nparam < 0 || n_in < 0)
    return isl_basic_map_free(bmap);
  i = isl_basic_map_alloc_inequality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->ineq[i], 1 + total);
  isl_int_set_si(bmap->ineq[i][1+nparam+pos], 1);
  isl_int_set_si(bmap->ineq[i][1+nparam+n_in+pos], -1);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_equal(
  __isl_take isl_space *space, unsigned n_equal)
{
  int i;
  struct isl_basic_map *bmap;
  bmap = isl_basic_map_alloc_space(space, 0, n_equal, 0);
  if (!bmap)
    return NULL;
  for (i = 0; i < n_equal && bmap; ++i)
    bmap = var_equal(bmap, i);
  return isl_basic_map_finalize(bmap);
}
 
/* Return a relation on of dimension "space" expressing i_[0..pos] << o_[0..pos]
 */
__isl_give isl_basic_map *isl_basic_map_less_at(__isl_take isl_space *space,
  unsigned pos)
{
  int i;
  struct isl_basic_map *bmap;
  bmap = isl_basic_map_alloc_space(space, 0, pos, 1);
  if (!bmap)
    return NULL;
  for (i = 0; i < pos && bmap; ++i)
    bmap = var_equal(bmap, i);
  if (bmap)
    bmap = var_less(bmap, pos);
  return isl_basic_map_finalize(bmap);
}
 
/* Return a relation on "space" expressing i_[0..pos] <<= o_[0..pos]
 */
__isl_give isl_basic_map *isl_basic_map_less_or_equal_at(
  __isl_take isl_space *space, unsigned pos)
{
  int i;
  isl_basic_map *bmap;
 
  bmap = isl_basic_map_alloc_space(space, 0, pos, 1);
  for (i = 0; i < pos; ++i)
    bmap = var_equal(bmap, i);
  bmap = var_less_or_equal(bmap, pos);
  return isl_basic_map_finalize(bmap);
}
 
/* Return a relation on "space" expressing i_pos > o_pos
 */
__isl_give isl_basic_map *isl_basic_map_more_at(__isl_take isl_space *space,
  unsigned pos)
{
  int i;
  struct isl_basic_map *bmap;
  bmap = isl_basic_map_alloc_space(space, 0, pos, 1);
  if (!bmap)
    return NULL;
  for (i = 0; i < pos && bmap; ++i)
    bmap = var_equal(bmap, i);
  if (bmap)
    bmap = var_more(bmap, pos);
  return isl_basic_map_finalize(bmap);
}
 
/* Return a relation on "space" expressing i_[0..pos] >>= o_[0..pos]
 */
__isl_give isl_basic_map *isl_basic_map_more_or_equal_at(
  __isl_take isl_space *space, unsigned pos)
{
  int i;
  isl_basic_map *bmap;
 
  bmap = isl_basic_map_alloc_space(space, 0, pos, 1);
  for (i = 0; i < pos; ++i)
    bmap = var_equal(bmap, i);
  bmap = var_more_or_equal(bmap, pos);
  return isl_basic_map_finalize(bmap);
}
 
static __isl_give isl_map *map_lex_lte_first(__isl_take isl_space *space,
  unsigned n, int equal)
{
  struct isl_map *map;
  int i;
 
  if (n == 0 && equal)
    return isl_map_universe(space);
 
  map = isl_map_alloc_space(isl_space_copy(space), n, ISL_MAP_DISJOINT);
 
  for (i = 0; i + 1 < n; ++i)
    map = isl_map_add_basic_map(map,
          isl_basic_map_less_at(isl_space_copy(space), i));
  if (n > 0) {
    if (equal)
      map = isl_map_add_basic_map(map,
            isl_basic_map_less_or_equal_at(space, n - 1));
    else
      map = isl_map_add_basic_map(map,
            isl_basic_map_less_at(space, n - 1));
  } else
    isl_space_free(space);
 
  return map;
}
 
static __isl_give isl_map *map_lex_lte(__isl_take isl_space *space, int equal)
{
  if (!space)
    return NULL;
  return map_lex_lte_first(space, space->n_out, equal);
}
 
__isl_give isl_map *isl_map_lex_lt_first(__isl_take isl_space *space,
  unsigned n)
{
  return map_lex_lte_first(space, n, 0);
}
 
__isl_give isl_map *isl_map_lex_le_first(__isl_take isl_space *space,
  unsigned n)
{
  return map_lex_lte_first(space, n, 1);
}
 
__isl_give isl_map *isl_map_lex_lt(__isl_take isl_space *set_space)
{
  return map_lex_lte(isl_space_map_from_set(set_space), 0);
}
 
__isl_give isl_map *isl_map_lex_le(__isl_take isl_space *set_space)
{
  return map_lex_lte(isl_space_map_from_set(set_space), 1);
}
 
static __isl_give isl_map *map_lex_gte_first(__isl_take isl_space *space,
  unsigned n, int equal)
{
  struct isl_map *map;
  int i;
 
  if (n == 0 && equal)
    return isl_map_universe(space);
 
  map = isl_map_alloc_space(isl_space_copy(space), n, ISL_MAP_DISJOINT);
 
  for (i = 0; i + 1 < n; ++i)
    map = isl_map_add_basic_map(map,
          isl_basic_map_more_at(isl_space_copy(space), i));
  if (n > 0) {
    if (equal)
      map = isl_map_add_basic_map(map,
            isl_basic_map_more_or_equal_at(space, n - 1));
    else
      map = isl_map_add_basic_map(map,
            isl_basic_map_more_at(space, n - 1));
  } else
    isl_space_free(space);
 
  return map;
}
 
static __isl_give isl_map *map_lex_gte(__isl_take isl_space *space, int equal)
{
  if (!space)
    return NULL;
  return map_lex_gte_first(space, space->n_out, equal);
}
 
__isl_give isl_map *isl_map_lex_gt_first(__isl_take isl_space *space,
  unsigned n)
{
  return map_lex_gte_first(space, n, 0);
}
 
__isl_give isl_map *isl_map_lex_ge_first(__isl_take isl_space *space,
  unsigned n)
{
  return map_lex_gte_first(space, n, 1);
}
 
__isl_give isl_map *isl_map_lex_gt(__isl_take isl_space *set_space)
{
  return map_lex_gte(isl_space_map_from_set(set_space), 0);
}
 
__isl_give isl_map *isl_map_lex_ge(__isl_take isl_space *set_space)
{
  return map_lex_gte(isl_space_map_from_set(set_space), 1);
}
 
__isl_give isl_map *isl_set_lex_le_set(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  isl_map *map;
  map = isl_map_lex_le(isl_set_get_space(set1));
  map = isl_map_intersect_domain(map, set1);
  map = isl_map_intersect_range(map, set2);
  return map;
}
 
__isl_give isl_map *isl_set_lex_lt_set(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  isl_map *map;
  map = isl_map_lex_lt(isl_set_get_space(set1));
  map = isl_map_intersect_domain(map, set1);
  map = isl_map_intersect_range(map, set2);
  return map;
}
 
__isl_give isl_map *isl_set_lex_ge_set(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  isl_map *map;
  map = isl_map_lex_ge(isl_set_get_space(set1));
  map = isl_map_intersect_domain(map, set1);
  map = isl_map_intersect_range(map, set2);
  return map;
}
 
__isl_give isl_map *isl_set_lex_gt_set(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  isl_map *map;
  map = isl_map_lex_gt(isl_set_get_space(set1));
  map = isl_map_intersect_domain(map, set1);
  map = isl_map_intersect_range(map, set2);
  return map;
}
 
__isl_give isl_map *isl_map_lex_le_map(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *map;
  map = isl_map_lex_le(isl_space_range(isl_map_get_space(map1)));
  map = isl_map_apply_domain(map, isl_map_reverse(map1));
  map = isl_map_apply_range(map, isl_map_reverse(map2));
  return map;
}
 
__isl_give isl_map *isl_map_lex_lt_map(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *map;
  map = isl_map_lex_lt(isl_space_range(isl_map_get_space(map1)));
  map = isl_map_apply_domain(map, isl_map_reverse(map1));
  map = isl_map_apply_range(map, isl_map_reverse(map2));
  return map;
}
 
__isl_give isl_map *isl_map_lex_ge_map(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *map;
  map = isl_map_lex_ge(isl_space_range(isl_map_get_space(map1)));
  map = isl_map_apply_domain(map, isl_map_reverse(map1));
  map = isl_map_apply_range(map, isl_map_reverse(map2));
  return map;
}
 
__isl_give isl_map *isl_map_lex_gt_map(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *map;
  map = isl_map_lex_gt(isl_space_range(isl_map_get_space(map1)));
  map = isl_map_apply_domain(map, isl_map_reverse(map1));
  map = isl_map_apply_range(map, isl_map_reverse(map2));
  return map;
}
 
/* For the div d = floor(f/m) at position "div", add the constraint
 *
 *    f - m d >= 0
 */
static __isl_give isl_basic_map *add_upper_div_constraint(
  __isl_take isl_basic_map *bmap, unsigned div)
{
  int i;
  isl_size v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  isl_size n_div;
  unsigned pos;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (v_div < 0 || n_div < 0)
    return isl_basic_map_free(bmap);
  pos = v_div + div;
  i = isl_basic_map_alloc_inequality(bmap);
  if (i < 0)
    return isl_basic_map_free(bmap);
  isl_seq_cpy(bmap->ineq[i], bmap->div[div] + 1, 1 + v_div + n_div);
  isl_int_neg(bmap->ineq[i][1 + pos], bmap->div[div][0]);
 
  return bmap;
}
 
/* For the div d = floor(f/m) at position "div", add the constraint
 *
 *    -(f-(m-1)) + m d >= 0
 */
static __isl_give isl_basic_map *add_lower_div_constraint(
  __isl_take isl_basic_map *bmap, unsigned div)
{
  int i;
  isl_size v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  isl_size n_div;
  unsigned pos;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (v_div < 0 || n_div < 0)
    return isl_basic_map_free(bmap);
  pos = v_div + div;
  i = isl_basic_map_alloc_inequality(bmap);
  if (i < 0)
    return isl_basic_map_free(bmap);
  isl_seq_neg(bmap->ineq[i], bmap->div[div] + 1, 1 + v_div + n_div);
  isl_int_set(bmap->ineq[i][1 + pos], bmap->div[div][0]);
  isl_int_add(bmap->ineq[i][0], bmap->ineq[i][0], bmap->ineq[i][1 + pos]);
  isl_int_sub_ui(bmap->ineq[i][0], bmap->ineq[i][0], 1);
 
  return bmap;
}
 
/* For the div d = floor(f/m) at position "pos", add the constraints
 *
 *    f - m d >= 0
 *    -(f-(m-1)) + m d >= 0
 *
 * Note that the second constraint is the negation of
 *
 *    f - m d >= m
 */
__isl_give isl_basic_map *isl_basic_map_add_div_constraints(
  __isl_take isl_basic_map *bmap, unsigned pos)
{
  bmap = add_upper_div_constraint(bmap, pos);
  bmap = add_lower_div_constraint(bmap, pos);
  return bmap;
}
 
/* For the div d = floor(f/m) at position "pos", add the constraints
 *
 *    f - m d >= 0
 *    -(f-(m-1)) + m d >= 0
 *
 * Note that the second constraint is the negation of
 *
 *    f - m d >= m
 */
__isl_give isl_basic_set *isl_basic_set_add_div_constraints(
  __isl_take isl_basic_set *bset, unsigned pos)
{
  isl_basic_map *bmap = bset_to_bmap(bset);
  bmap = isl_basic_map_add_div_constraints(bmap, pos);
  return bset_from_bmap(bmap);
}
 
/* For each known div d = floor(f/m), add the constraints
 *
 *    f - m d >= 0
 *    -(f-(m-1)) + m d >= 0
 *
 * Remove duplicate constraints in case of some these div constraints
 * already appear in "bmap".
 */
__isl_give isl_basic_map *isl_basic_map_add_known_div_constraints(
  __isl_take isl_basic_map *bmap)
{
  isl_size n_div;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_div < 0)
    return isl_basic_map_free(bmap);
  if (n_div == 0)
    return bmap;
 
  bmap = add_known_div_constraints(bmap);
  bmap = isl_basic_map_remove_duplicate_constraints(bmap, NULL, 0);
  bmap = isl_basic_map_finalize(bmap);
  return bmap;
}
 
/* Add the div constraint of sign "sign" for div "div" of "bmap".
 *
 * In particular, if this div is of the form d = floor(f/m),
 * then add the constraint
 *
 *    f - m d >= 0
 *
 * if sign < 0 or the constraint
 *
 *    -(f-(m-1)) + m d >= 0
 *
 * if sign > 0.
 */
__isl_give isl_basic_map *isl_basic_map_add_div_constraint(
  __isl_take isl_basic_map *bmap, unsigned div, int sign)
{
  if (sign < 0)
    return add_upper_div_constraint(bmap, div);
  else
    return add_lower_div_constraint(bmap, div);
}
 
__isl_give isl_basic_set *isl_basic_map_underlying_set(
  __isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  if (!bmap)
    goto error;
  if (bmap->dim->nparam == 0 && bmap->dim->n_in == 0 &&
      bmap->n_div == 0 &&
      !isl_space_is_named_or_nested(bmap->dim, isl_dim_in) &&
      !isl_space_is_named_or_nested(bmap->dim, isl_dim_out))
    return bset_from_bmap(bmap);
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
  space = isl_basic_map_take_space(bmap);
  space = isl_space_underlying(space, bmap->n_div);
  bmap = isl_basic_map_restore_space(bmap, space);
  if (!bmap)
    return NULL;
  bmap->extra -= bmap->n_div;
  bmap->n_div = 0;
  bmap = isl_basic_map_finalize(bmap);
  return bset_from_bmap(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_underlying_set(
    __isl_take isl_basic_set *bset)
{
  return isl_basic_map_underlying_set(bset_to_bmap(bset));
}
 
/* Replace each element in "list" by the result of applying
 * isl_basic_map_underlying_set to the element.
 */
__isl_give isl_basic_set_list *isl_basic_map_list_underlying_set(
  __isl_take isl_basic_map_list *list)
{
  int i;
  isl_size n;
 
  n = isl_basic_map_list_n_basic_map(list);
  if (n < 0)
    goto error;
 
  for (i = 0; i < n; ++i) {
    isl_basic_map *bmap;
    isl_basic_set *bset;
 
    bmap = isl_basic_map_list_get_basic_map(list, i);
    bset = isl_basic_set_underlying_set(bmap);
    list = isl_basic_set_list_set_basic_set(list, i, bset);
  }
 
  return list;
error:
  isl_basic_map_list_free(list);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_overlying_set(
  __isl_take isl_basic_set *bset, __isl_take isl_basic_map *like)
{
  struct isl_basic_map *bmap;
  struct isl_ctx *ctx;
  isl_size dim, bmap_total;
  unsigned total;
  int i;
 
  if (!bset || !like)
    goto error;
  ctx = bset->ctx;
  if (isl_basic_set_check_no_params(bset) < 0 ||
      isl_basic_set_check_no_locals(bset) < 0)
    goto error;
  dim = isl_basic_set_dim(bset, isl_dim_set);
  bmap_total = isl_basic_map_dim(like, isl_dim_all);
  if (dim < 0 || bmap_total < 0)
    goto error;
  isl_assert(ctx, dim == bmap_total, goto error);
  if (like->n_div == 0) {
    isl_space *space = isl_basic_map_get_space(like);
    isl_basic_map_free(like);
    return isl_basic_map_reset_space(bset, space);
  }
  bset = isl_basic_set_cow(bset);
  if (!bset)
    goto error;
  total = dim + bset->extra;
  bmap = bset_to_bmap(bset);
  isl_space_free(isl_basic_map_take_space(bmap));
  bmap = isl_basic_map_restore_space(bmap, isl_basic_map_get_space(like));
  if (!bmap)
    goto error;
  bmap->n_div = like->n_div;
  bmap->extra += like->n_div;
  if (bmap->extra) {
    unsigned ltotal;
    isl_int **div;
    ltotal = total - bmap->extra + like->extra;
    if (ltotal > total)
      ltotal = total;
    bmap->block2 = isl_blk_extend(ctx, bmap->block2,
          bmap->extra * (1 + 1 + total));
    if (isl_blk_is_error(bmap->block2))
      goto error;
    div = isl_realloc_array(ctx, bmap->div, isl_int *, bmap->extra);
    if (!div)
      goto error;
    bmap->div = div;
    for (i = 0; i < bmap->extra; ++i)
      bmap->div[i] = bmap->block2.data + i * (1 + 1 + total);
    for (i = 0; i < like->n_div; ++i) {
      isl_seq_cpy(bmap->div[i], like->div[i], 1 + 1 + ltotal);
      isl_seq_clr(bmap->div[i]+1+1+ltotal, total - ltotal);
    }
    bmap = isl_basic_map_add_known_div_constraints(bmap);
  }
  isl_basic_map_free(like);
  bmap = isl_basic_map_simplify(bmap);
  bmap = isl_basic_map_finalize(bmap);
  return bmap;
error:
  isl_basic_map_free(like);
  isl_basic_set_free(bset);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_from_underlying_set(
  __isl_take isl_basic_set *bset, __isl_take isl_basic_set *like)
{
  return bset_from_bmap(isl_basic_map_overlying_set(bset,
              bset_to_bmap(like)));
}
 
__isl_give isl_set *isl_map_underlying_set(__isl_take isl_map *map)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
  map->dim = isl_space_cow(map->dim);
  if (!map->dim)
    goto error;
 
  for (i = 1; i < map->n; ++i)
    isl_assert(map->ctx, map->p[0]->n_div == map->p[i]->n_div,
        goto error);
  for (i = 0; i < map->n; ++i) {
    map->p[i] = bset_to_bmap(
        isl_basic_map_underlying_set(map->p[i]));
    if (!map->p[i])
      goto error;
  }
  if (map->n == 0)
    map->dim = isl_space_underlying(map->dim, 0);
  else {
    isl_space_free(map->dim);
    map->dim = isl_space_copy(map->p[0]->dim);
  }
  if (!map->dim)
    goto error;
  return set_from_map(map);
error:
  isl_map_free(map);
  return NULL;
}
 
/* Replace the space of "bmap" by "space".
 *
 * If the space of "bmap" is identical to "space" (including the identifiers
 * of the input and output dimensions), then simply return the original input.
 */
__isl_give isl_basic_map *isl_basic_map_reset_space(
  __isl_take isl_basic_map *bmap, __isl_take isl_space *space)
{
  isl_bool equal;
  isl_space *bmap_space;
 
  bmap_space = isl_basic_map_peek_space(bmap);
  equal = isl_space_is_equal(bmap_space, space);
  if (equal >= 0 && equal)
    equal = isl_space_has_equal_ids(bmap_space, space);
  if (equal < 0)
    goto error;
  if (equal) {
    isl_space_free(space);
    return bmap;
  }
  isl_space_free(isl_basic_map_take_space(bmap));
  bmap = isl_basic_map_restore_space(bmap, space);
 
  bmap = isl_basic_map_finalize(bmap);
 
  return bmap;
error:
  isl_basic_map_free(bmap);
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_reset_space(
  __isl_take isl_basic_set *bset, __isl_take isl_space *space)
{
  return bset_from_bmap(isl_basic_map_reset_space(bset_to_bmap(bset),
              space));
}
 
/* Check that the total dimensions of "map" and "space" are the same.
 */
static isl_stat check_map_space_equal_total_dim(__isl_keep isl_map *map,
  __isl_keep isl_space *space)
{
  isl_size dim1, dim2;
 
  dim1 = isl_map_dim(map, isl_dim_all);
  dim2 = isl_space_dim(space, isl_dim_all);
  if (dim1 < 0 || dim2 < 0)
    return isl_stat_error;
  if (dim1 == dim2)
    return isl_stat_ok;
  isl_die(isl_map_get_ctx(map), isl_error_invalid,
    "total dimensions do not match", return isl_stat_error);
}
 
__isl_give isl_map *isl_map_reset_space(__isl_take isl_map *map,
  __isl_take isl_space *space)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map || !space)
    goto error;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_reset_space(map->p[i],
                isl_space_copy(space));
    if (!map->p[i])
      goto error;
  }
  isl_space_free(isl_map_take_space(map));
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  isl_space_free(space);
  return NULL;
}
 
/* Replace the space of "map" by "space", without modifying
 * the dimension of "map".
 *
 * If the space of "map" is identical to "space" (including the identifiers
 * of the input and output dimensions), then simply return the original input.
 */
__isl_give isl_map *isl_map_reset_equal_dim_space(__isl_take isl_map *map,
  __isl_take isl_space *space)
{
  isl_bool equal;
  isl_space *map_space;
 
  map_space = isl_map_peek_space(map);
  equal = isl_space_is_equal(map_space, space);
  if (equal >= 0 && equal)
    equal = isl_space_has_equal_ids(map_space, space);
  if (equal < 0)
    goto error;
  if (equal) {
    isl_space_free(space);
    return map;
  }
  if (check_map_space_equal_total_dim(map, space) < 0)
    goto error;
  return isl_map_reset_space(map, space);
error:
  isl_map_free(map);
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_set *isl_set_reset_space(__isl_take isl_set *set,
  __isl_take isl_space *space)
{
  return set_from_map(isl_map_reset_space(set_to_map(set), space));
}
 
/* Compute the parameter domain of the given basic set.
 */
__isl_give isl_basic_set *isl_basic_set_params(__isl_take isl_basic_set *bset)
{
  isl_bool is_params;
  isl_space *space;
  isl_size n;
 
  is_params = isl_basic_set_is_params(bset);
  if (is_params < 0)
    return isl_basic_set_free(bset);
  if (is_params)
    return bset;
 
  n = isl_basic_set_dim(bset, isl_dim_set);
  if (n < 0)
    return isl_basic_set_free(bset);
  bset = isl_basic_set_project_out(bset, isl_dim_set, 0, n);
  space = isl_basic_set_get_space(bset);
  space = isl_space_params(space);
  bset = isl_basic_set_reset_space(bset, space);
  return bset;
}
 
/* Construct a zero-dimensional basic set with the given parameter domain.
 */
__isl_give isl_basic_set *isl_basic_set_from_params(
  __isl_take isl_basic_set *bset)
{
  isl_space *space;
  space = isl_basic_set_get_space(bset);
  space = isl_space_set_from_params(space);
  bset = isl_basic_set_reset_space(bset, space);
  return bset;
}
 
/* Compute the parameter domain of the given set.
 */
__isl_give isl_set *isl_set_params(__isl_take isl_set *set)
{
  return isl_map_params(set_to_map(set));
}
 
/* Construct a zero-dimensional set with the given parameter domain.
 */
__isl_give isl_set *isl_set_from_params(__isl_take isl_set *set)
{
  isl_space *space;
  space = isl_set_get_space(set);
  space = isl_space_set_from_params(space);
  set = isl_set_reset_space(set, space);
  return set;
}
 
/* Compute the parameter domain of the given map.
 */
__isl_give isl_set *isl_map_params(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size n_in, n_out;
 
  n_in = isl_map_dim(map, isl_dim_in);
  n_out = isl_map_dim(map, isl_dim_out);
  if (n_in < 0 || n_out < 0)
    return isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_in, 0, n_in);
  map = isl_map_project_out(map, isl_dim_out, 0, n_out);
  space = isl_map_get_space(map);
  space = isl_space_params(space);
  map = isl_map_reset_space(map, space);
  return map;
}
 
__isl_give isl_basic_set *isl_basic_map_domain(__isl_take isl_basic_map *bmap)
{
  isl_space *space;
  isl_size n_out;
 
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (n_out < 0)
    return isl_basic_map_free(bmap);
  space = isl_space_domain(isl_basic_map_get_space(bmap));
 
  bmap = isl_basic_map_project_out(bmap, isl_dim_out, 0, n_out);
 
  return isl_basic_map_reset_space(bmap, space);
}
 
isl_bool isl_basic_map_may_be_set(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
  return isl_space_may_be_set(bmap->dim);
}
 
/* Is this basic map actually a set?
 * Users should never call this function.  Outside of isl,
 * the type should indicate whether something is a set or a map.
 */
isl_bool isl_basic_map_is_set(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
  return isl_space_is_set(bmap->dim);
}
 
__isl_give isl_basic_set *isl_basic_map_range(__isl_take isl_basic_map *bmap)
{
  isl_bool is_set;
 
  is_set = isl_basic_map_is_set(bmap);
  if (is_set < 0)
    goto error;
  if (is_set)
    return bmap;
  return isl_basic_map_domain(isl_basic_map_reverse(bmap));
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_domain_map(
  __isl_take isl_basic_map *bmap)
{
  int i;
  isl_space *space;
  isl_basic_map *domain;
  isl_size nparam, n_in, n_out;
 
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (nparam < 0 || n_in < 0 || n_out < 0)
    return isl_basic_map_free(bmap);
 
  space = isl_basic_map_get_space(bmap);
  space = isl_space_from_range(isl_space_domain(space));
  domain = isl_basic_map_universe(space);
 
  bmap = isl_basic_map_from_domain(isl_basic_map_wrap(bmap));
  bmap = isl_basic_map_apply_range(bmap, domain);
  bmap = isl_basic_map_extend_constraints(bmap, n_in, 0);
 
  for (i = 0; i < n_in; ++i)
    bmap = isl_basic_map_equate(bmap, isl_dim_in, i,
                isl_dim_out, i);
 
  bmap = isl_basic_map_gauss(bmap, NULL);
  return isl_basic_map_finalize(bmap);
}
 
__isl_give isl_basic_map *isl_basic_map_range_map(
  __isl_take isl_basic_map *bmap)
{
  int i;
  isl_space *space;
  isl_basic_map *range;
  isl_size nparam, n_in, n_out;
 
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (nparam < 0 || n_in < 0 || n_out < 0)
    return isl_basic_map_free(bmap);
 
  space = isl_basic_map_get_space(bmap);
  space = isl_space_from_range(isl_space_range(space));
  range = isl_basic_map_universe(space);
 
  bmap = isl_basic_map_from_domain(isl_basic_map_wrap(bmap));
  bmap = isl_basic_map_apply_range(bmap, range);
  bmap = isl_basic_map_extend_constraints(bmap, n_out, 0);
 
  for (i = 0; i < n_out; ++i)
    bmap = isl_basic_map_equate(bmap, isl_dim_in, n_in + i,
                isl_dim_out, i);
 
  bmap = isl_basic_map_gauss(bmap, NULL);
  return isl_basic_map_finalize(bmap);
}
 
int isl_map_may_be_set(__isl_keep isl_map *map)
{
  if (!map)
    return -1;
  return isl_space_may_be_set(map->dim);
}
 
/* Is this map actually a set?
 * Users should never call this function.  Outside of isl,
 * the type should indicate whether something is a set or a map.
 */
isl_bool isl_map_is_set(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
  return isl_space_is_set(map->dim);
}
 
__isl_give isl_set *isl_map_range(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size n_in;
 
  n_in = isl_map_dim(map, isl_dim_in);
  if (n_in < 0)
    return set_from_map(isl_map_free(map));
  space = isl_space_range(isl_map_get_space(map));
 
  map = isl_map_project_out(map, isl_dim_in, 0, n_in);
 
  return set_from_map(isl_map_reset_space(map, space));
}
 
/* Transform "map" by applying "fn_space" to its space and "fn_bmap"
 * to each of its basic maps.
 */
static __isl_give isl_map *isl_map_transform(__isl_take isl_map *map,
  __isl_give isl_space *(*fn_space)(__isl_take isl_space *space),
  __isl_give isl_basic_map *(*fn_bmap)(__isl_take isl_basic_map *bmap))
{
  int i;
  isl_space *space;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = fn_bmap(map->p[i]);
    if (!map->p[i])
      return isl_map_free(map);
  }
  map = isl_map_unmark_normalized(map);
 
  space = isl_map_take_space(map);
  space = fn_space(space);
  map = isl_map_restore_space(map, space);
 
  return map;
}
 
__isl_give isl_map *isl_map_domain_map(__isl_take isl_map *map)
{
  return isl_map_transform(map, &isl_space_domain_map,
          &isl_basic_map_domain_map);
}
 
__isl_give isl_map *isl_map_range_map(__isl_take isl_map *map)
{
  return isl_map_transform(map, &isl_space_range_map,
          &isl_basic_map_range_map);
}
 
/* Given a wrapped map of the form A[B -> C],
 * return the map A[B -> C] -> B.
 */
__isl_give isl_map *isl_set_wrapped_domain_map(__isl_take isl_set *set)
{
  isl_id *id;
  isl_map *map;
 
  if (!set)
    return NULL;
  if (!isl_set_has_tuple_id(set))
    return isl_map_domain_map(isl_set_unwrap(set));
 
  id = isl_set_get_tuple_id(set);
  map = isl_map_domain_map(isl_set_unwrap(set));
  map = isl_map_set_tuple_id(map, isl_dim_in, id);
 
  return map;
}
 
__isl_give isl_basic_map *isl_basic_map_from_domain(
  __isl_take isl_basic_set *bset)
{
  return isl_basic_map_reverse(isl_basic_map_from_range(bset));
}
 
__isl_give isl_basic_map *isl_basic_map_from_range(
  __isl_take isl_basic_set *bset)
{
  isl_space *space;
  space = isl_basic_set_get_space(bset);
  space = isl_space_from_range(space);
  bset = isl_basic_set_reset_space(bset, space);
  return bset_to_bmap(bset);
}
 
/* Create a relation with the given set as range.
 * The domain of the created relation is a zero-dimensional
 * flat anonymous space.
 */
__isl_give isl_map *isl_map_from_range(__isl_take isl_set *set)
{
  isl_space *space;
  space = isl_set_get_space(set);
  space = isl_space_from_range(space);
  set = isl_set_reset_space(set, space);
  return set_to_map(set);
}
 
/* Create a relation with the given set as domain.
 * The range of the created relation is a zero-dimensional
 * flat anonymous space.
 */
__isl_give isl_map *isl_map_from_domain(__isl_take isl_set *set)
{
  return isl_map_reverse(isl_map_from_range(set));
}
 
__isl_give isl_basic_map *isl_basic_map_from_domain_and_range(
  __isl_take isl_basic_set *domain, __isl_take isl_basic_set *range)
{
  return isl_basic_map_apply_range(isl_basic_map_reverse(domain), range);
}
 
__isl_give isl_map *isl_map_from_domain_and_range(__isl_take isl_set *domain,
  __isl_take isl_set *range)
{
  return isl_map_apply_range(isl_map_reverse(domain), range);
}
 
/* Return a newly allocated isl_map with given space and flags and
 * room for "n" basic maps.
 * Make sure that all cached information is cleared.
 */
__isl_give isl_map *isl_map_alloc_space(__isl_take isl_space *space, int n,
  unsigned flags)
{
  struct isl_map *map;
 
  if (!space)
    return NULL;
  if (n < 0)
    isl_die(space->ctx, isl_error_internal,
      "negative number of basic maps", goto error);
  map = isl_calloc(space->ctx, struct isl_map,
      sizeof(struct isl_map) +
      (n - 1) * sizeof(struct isl_basic_map *));
  if (!map)
    goto error;
 
  map->ctx = space->ctx;
  isl_ctx_ref(map->ctx);
  map->ref = 1;
  map->size = n;
  map->n = 0;
  map->dim = space;
  map->flags = flags;
  return map;
error:
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_empty(__isl_take isl_space *space)
{
  struct isl_basic_map *bmap;
  bmap = isl_basic_map_alloc_space(space, 0, 1, 0);
  bmap = isl_basic_map_set_to_empty(bmap);
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_empty(__isl_take isl_space *space)
{
  struct isl_basic_set *bset;
  bset = isl_basic_set_alloc_space(space, 0, 1, 0);
  bset = isl_basic_set_set_to_empty(bset);
  return bset;
}
 
__isl_give isl_basic_map *isl_basic_map_universe(__isl_take isl_space *space)
{
  struct isl_basic_map *bmap;
  bmap = isl_basic_map_alloc_space(space, 0, 0, 0);
  bmap = isl_basic_map_finalize(bmap);
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_universe(__isl_take isl_space *space)
{
  struct isl_basic_set *bset;
  bset = isl_basic_set_alloc_space(space, 0, 0, 0);
  bset = isl_basic_set_finalize(bset);
  return bset;
}
 
__isl_give isl_basic_map *isl_basic_map_nat_universe(
  __isl_take isl_space *space)
{
  int i;
  isl_size total = isl_space_dim(space, isl_dim_all);
  isl_basic_map *bmap;
 
  if (total < 0)
    space = isl_space_free(space);
  bmap = isl_basic_map_alloc_space(space, 0, 0, total);
  for (i = 0; i < total; ++i) {
    int k = isl_basic_map_alloc_inequality(bmap);
    if (k < 0)
      goto error;
    isl_seq_clr(bmap->ineq[k], 1 + total);
    isl_int_set_si(bmap->ineq[k][1 + i], 1);
  }
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_set *isl_basic_set_nat_universe(
  __isl_take isl_space *space)
{
  return isl_basic_map_nat_universe(space);
}
 
__isl_give isl_map *isl_map_nat_universe(__isl_take isl_space *space)
{
  return isl_map_from_basic_map(isl_basic_map_nat_universe(space));
}
 
__isl_give isl_set *isl_set_nat_universe(__isl_take isl_space *space)
{
  return isl_map_nat_universe(space);
}
 
__isl_give isl_map *isl_map_empty(__isl_take isl_space *space)
{
  return isl_map_alloc_space(space, 0, ISL_MAP_DISJOINT);
}
 
__isl_give isl_set *isl_set_empty(__isl_take isl_space *space)
{
  return isl_set_alloc_space(space, 0, ISL_MAP_DISJOINT);
}
 
__isl_give isl_map *isl_map_universe(__isl_take isl_space *space)
{
  struct isl_map *map;
  if (!space)
    return NULL;
  map = isl_map_alloc_space(isl_space_copy(space), 1, ISL_MAP_DISJOINT);
  map = isl_map_add_basic_map(map, isl_basic_map_universe(space));
  return map;
}
 
/* This function performs the same operation as isl_map_universe,
 * but is considered as a function on an isl_space when exported.
 */
__isl_give isl_map *isl_space_universe_map(__isl_take isl_space *space)
{
  return isl_map_universe(space);
}
 
__isl_give isl_set *isl_set_universe(__isl_take isl_space *space)
{
  struct isl_set *set;
  if (!space)
    return NULL;
  set = isl_set_alloc_space(isl_space_copy(space), 1, ISL_MAP_DISJOINT);
  set = isl_set_add_basic_set(set, isl_basic_set_universe(space));
  return set;
}
 
/* This function performs the same operation as isl_set_universe,
 * but is considered as a function on an isl_space when exported.
 */
__isl_give isl_set *isl_space_universe_set(__isl_take isl_space *space)
{
  return isl_set_universe(space);
}
 
__isl_give isl_map *isl_map_dup(__isl_keep isl_map *map)
{
  int i;
  struct isl_map *dup;
 
  if (!map)
    return NULL;
  dup = isl_map_alloc_space(isl_space_copy(map->dim), map->n, map->flags);
  for (i = 0; i < map->n; ++i)
    dup = isl_map_add_basic_map(dup, isl_basic_map_copy(map->p[i]));
  return dup;
}
 
__isl_give isl_map *isl_map_add_basic_map(__isl_take isl_map *map,
            __isl_take isl_basic_map *bmap)
{
  if (!bmap || !map)
    goto error;
  if (isl_basic_map_plain_is_empty(bmap)) {
    isl_basic_map_free(bmap);
    return map;
  }
  if (isl_map_basic_map_check_equal_space(map, bmap) < 0)
    goto error;
  isl_assert(map->ctx, map->n < map->size, goto error);
  map->p[map->n] = bmap;
  map->n++;
  map = isl_map_unmark_normalized(map);
  return map;
error:
  if (map)
    isl_map_free(map);
  if (bmap)
    isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_null isl_map *isl_map_free(__isl_take isl_map *map)
{
  int i;
 
  if (!map)
    return NULL;
 
  if (--map->ref > 0)
    return NULL;
 
  clear_caches(map);
  isl_ctx_deref(map->ctx);
  for (i = 0; i < map->n; ++i)
    isl_basic_map_free(map->p[i]);
  isl_space_free(map->dim);
  free(map);
 
  return NULL;
}
 
static __isl_give isl_basic_map *isl_basic_map_fix_pos_si(
  __isl_take isl_basic_map *bmap, unsigned pos, int value)
{
  int j;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
 
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 1, 0);
  j = isl_basic_map_alloc_equality(bmap);
  if (j < 0)
    goto error;
  isl_seq_clr(bmap->eq[j] + 1, total);
  isl_int_set_si(bmap->eq[j][pos], -1);
  isl_int_set_si(bmap->eq[j][0], value);
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
static __isl_give isl_basic_map *isl_basic_map_fix_pos(
  __isl_take isl_basic_map *bmap, unsigned pos, isl_int value)
{
  int j;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
 
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 1, 0);
  j = isl_basic_map_alloc_equality(bmap);
  if (j < 0)
    goto error;
  isl_seq_clr(bmap->eq[j] + 1, total);
  isl_int_set_si(bmap->eq[j][pos], -1);
  isl_int_set(bmap->eq[j][0], value);
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_fix_si(__isl_take isl_basic_map *bmap,
    enum isl_dim_type type, unsigned pos, int value)
{
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    return isl_basic_map_free(bmap);
  return isl_basic_map_fix_pos_si(bmap,
    isl_basic_map_offset(bmap, type) + pos, value);
}
 
__isl_give isl_basic_map *isl_basic_map_fix(__isl_take isl_basic_map *bmap,
    enum isl_dim_type type, unsigned pos, isl_int value)
{
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    return isl_basic_map_free(bmap);
  return isl_basic_map_fix_pos(bmap,
    isl_basic_map_offset(bmap, type) + pos, value);
}
 
/* Fix the value of the variable at position "pos" of type "type" of "bmap"
 * to be equal to "v".
 */
__isl_give isl_basic_map *isl_basic_map_fix_val(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *v)
{
  if (!bmap || !v)
    goto error;
  if (!isl_val_is_int(v))
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "expecting integer value", goto error);
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    goto error;
  pos += isl_basic_map_offset(bmap, type);
  bmap = isl_basic_map_fix_pos(bmap, pos, v->n);
  isl_val_free(v);
  return bmap;
error:
  isl_basic_map_free(bmap);
  isl_val_free(v);
  return NULL;
}
 
/* Fix the value of the variable at position "pos" of type "type" of "bset"
 * to be equal to "v".
 */
__isl_give isl_basic_set *isl_basic_set_fix_val(__isl_take isl_basic_set *bset,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *v)
{
  return isl_basic_map_fix_val(bset, type, pos, v);
}
 
__isl_give isl_basic_set *isl_basic_set_fix_si(__isl_take isl_basic_set *bset,
    enum isl_dim_type type, unsigned pos, int value)
{
  return bset_from_bmap(isl_basic_map_fix_si(bset_to_bmap(bset),
                type, pos, value));
}
 
__isl_give isl_basic_set *isl_basic_set_fix(__isl_take isl_basic_set *bset,
    enum isl_dim_type type, unsigned pos, isl_int value)
{
  return bset_from_bmap(isl_basic_map_fix(bset_to_bmap(bset),
                type, pos, value));
}
 
/* Remove the basic map at position "i" from "map" if this basic map
 * is (obviously) empty.
 */
static __isl_give isl_map *remove_if_empty(__isl_take isl_map *map, int i)
{
  isl_bool empty;
 
  if (!map)
    return NULL;
 
  empty = isl_basic_map_plain_is_empty(map->p[i]);
  if (empty < 0)
    return isl_map_free(map);
  if (!empty)
    return map;
 
  isl_basic_map_free(map->p[i]);
  map->n--;
  if (i != map->n) {
    map->p[i] = map->p[map->n];
    map = isl_map_unmark_normalized(map);
 
  }
 
  return map;
}
 
/* Perform "fn" on each basic map of "map", where we may not be holding
 * the only reference to "map".
 * In particular, "fn" should be a semantics preserving operation
 * that we want to apply to all copies of "map".  We therefore need
 * to be careful not to modify "map" in a way that breaks "map"
 * in case anything goes wrong.
 */
__isl_give isl_map *isl_map_inline_foreach_basic_map(__isl_take isl_map *map,
  __isl_give isl_basic_map *(*fn)(__isl_take isl_basic_map *bmap))
{
  struct isl_basic_map *bmap;
  int i;
 
  if (!map)
    return NULL;
 
  for (i = map->n - 1; i >= 0; --i) {
    bmap = isl_basic_map_copy(map->p[i]);
    bmap = fn(bmap);
    if (!bmap)
      goto error;
    isl_basic_map_free(map->p[i]);
    map->p[i] = bmap;
    map = remove_if_empty(map, i);
    if (!map)
      return NULL;
  }
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_map *isl_map_fix_si(__isl_take isl_map *map,
    enum isl_dim_type type, unsigned pos, int value)
{
  int i;
 
  map = isl_map_cow(map);
  if (isl_map_check_range(map, type, pos, 1) < 0)
    return isl_map_free(map);
  for (i = map->n - 1; i >= 0; --i) {
    map->p[i] = isl_basic_map_fix_si(map->p[i], type, pos, value);
    map = remove_if_empty(map, i);
    if (!map)
      return NULL;
  }
  map = isl_map_unmark_normalized(map);
  return map;
}
 
__isl_give isl_set *isl_set_fix_si(__isl_take isl_set *set,
    enum isl_dim_type type, unsigned pos, int value)
{
  return set_from_map(isl_map_fix_si(set_to_map(set), type, pos, value));
}
 
__isl_give isl_map *isl_map_fix(__isl_take isl_map *map,
    enum isl_dim_type type, unsigned pos, isl_int value)
{
  int i;
 
  map = isl_map_cow(map);
  if (isl_map_check_range(map, type, pos, 1) < 0)
    return isl_map_free(map);
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_fix(map->p[i], type, pos, value);
    if (!map->p[i])
      goto error;
  }
  map = isl_map_unmark_normalized(map);
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_fix(__isl_take isl_set *set,
    enum isl_dim_type type, unsigned pos, isl_int value)
{
  return set_from_map(isl_map_fix(set_to_map(set), type, pos, value));
}
 
/* Fix the value of the variable at position "pos" of type "type" of "map"
 * to be equal to "v".
 */
__isl_give isl_map *isl_map_fix_val(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *v)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map || !v)
    goto error;
 
  if (!isl_val_is_int(v))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "expecting integer value", goto error);
  if (isl_map_check_range(map, type, pos, 1) < 0)
    goto error;
  for (i = map->n - 1; i >= 0; --i) {
    map->p[i] = isl_basic_map_fix_val(map->p[i], type, pos,
              isl_val_copy(v));
    map = remove_if_empty(map, i);
    if (!map)
      goto error;
  }
  map = isl_map_unmark_normalized(map);
  isl_val_free(v);
  return map;
error:
  isl_map_free(map);
  isl_val_free(v);
  return NULL;
}
 
/* Fix the value of the variable at position "pos" of type "type" of "set"
 * to be equal to "v".
 */
__isl_give isl_set *isl_set_fix_val(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *v)
{
  return isl_map_fix_val(set, type, pos, v);
}
 
__isl_give isl_map *isl_map_fix_input_si(__isl_take isl_map *map,
    unsigned input, int value)
{
  return isl_map_fix_si(map, isl_dim_in, input, value);
}
 
__isl_give isl_set *isl_set_fix_dim_si(__isl_take isl_set *set, unsigned dim,
  int value)
{
  return set_from_map(isl_map_fix_si(set_to_map(set),
            isl_dim_set, dim, value));
}
 
static __isl_give isl_basic_map *basic_map_bound_si(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, int value, int upper)
{
  int j;
  isl_size total;
 
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    return isl_basic_map_free(bmap);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  pos += isl_basic_map_offset(bmap, type);
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 0, 1);
  j = isl_basic_map_alloc_inequality(bmap);
  if (j < 0)
    goto error;
  isl_seq_clr(bmap->ineq[j], 1 + total);
  if (upper) {
    isl_int_set_si(bmap->ineq[j][pos], -1);
    isl_int_set_si(bmap->ineq[j][0], value);
  } else {
    isl_int_set_si(bmap->ineq[j][pos], 1);
    isl_int_set_si(bmap->ineq[j][0], -value);
  }
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_lower_bound_si(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, int value)
{
  return basic_map_bound_si(bmap, type, pos, value, 0);
}
 
/* Constrain the values of the given dimension to be no greater than "value".
 */
__isl_give isl_basic_map *isl_basic_map_upper_bound_si(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, int value)
{
  return basic_map_bound_si(bmap, type, pos, value, 1);
}
 
static __isl_give isl_map *map_bound_si(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, int value, int upper)
{
  int i;
 
  map = isl_map_cow(map);
  if (isl_map_check_range(map, type, pos, 1) < 0)
    return isl_map_free(map);
  for (i = 0; i < map->n; ++i) {
    map->p[i] = basic_map_bound_si(map->p[i],
             type, pos, value, upper);
    if (!map->p[i])
      goto error;
  }
  map = isl_map_unmark_normalized(map);
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_map *isl_map_lower_bound_si(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, int value)
{
  return map_bound_si(map, type, pos, value, 0);
}
 
__isl_give isl_map *isl_map_upper_bound_si(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, int value)
{
  return map_bound_si(map, type, pos, value, 1);
}
 
__isl_give isl_set *isl_set_lower_bound_si(__isl_take isl_set *set,
    enum isl_dim_type type, unsigned pos, int value)
{
  return set_from_map(isl_map_lower_bound_si(set_to_map(set),
              type, pos, value));
}
 
__isl_give isl_set *isl_set_upper_bound_si(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, int value)
{
  return isl_map_upper_bound_si(set, type, pos, value);
}
 
/* Bound the given variable of "bmap" from below (or above is "upper"
 * is set) to "value".
 */
static __isl_give isl_basic_map *basic_map_bound(
  __isl_take isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, isl_int value, int upper)
{
  int j;
  isl_size total;
 
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    return isl_basic_map_free(bmap);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  pos += isl_basic_map_offset(bmap, type);
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, 0, 1);
  j = isl_basic_map_alloc_inequality(bmap);
  if (j < 0)
    goto error;
  isl_seq_clr(bmap->ineq[j], 1 + total);
  if (upper) {
    isl_int_set_si(bmap->ineq[j][pos], -1);
    isl_int_set(bmap->ineq[j][0], value);
  } else {
    isl_int_set_si(bmap->ineq[j][pos], 1);
    isl_int_neg(bmap->ineq[j][0], value);
  }
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Bound the given variable of "map" from below (or above is "upper"
 * is set) to "value".
 */
static __isl_give isl_map *map_bound(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, isl_int value, int upper)
{
  int i;
 
  map = isl_map_cow(map);
  if (isl_map_check_range(map, type, pos, 1) < 0)
    return isl_map_free(map);
  for (i = map->n - 1; i >= 0; --i) {
    map->p[i] = basic_map_bound(map->p[i], type, pos, value, upper);
    map = remove_if_empty(map, i);
    if (!map)
      return NULL;
  }
  map = isl_map_unmark_normalized(map);
  return map;
}
 
__isl_give isl_map *isl_map_lower_bound(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, isl_int value)
{
  return map_bound(map, type, pos, value, 0);
}
 
__isl_give isl_map *isl_map_upper_bound(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, isl_int value)
{
  return map_bound(map, type, pos, value, 1);
}
 
__isl_give isl_set *isl_set_lower_bound(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, isl_int value)
{
  return isl_map_lower_bound(set, type, pos, value);
}
 
__isl_give isl_set *isl_set_upper_bound(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, isl_int value)
{
  return isl_map_upper_bound(set, type, pos, value);
}
 
/* Force the values of the variable at position "pos" of type "type" of "map"
 * to be no smaller than "value".
 */
__isl_give isl_map *isl_map_lower_bound_val(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *value)
{
  if (!value)
    goto error;
  if (!isl_val_is_int(value))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "expecting integer value", goto error);
  map = isl_map_lower_bound(map, type, pos, value->n);
  isl_val_free(value);
  return map;
error:
  isl_val_free(value);
  isl_map_free(map);
  return NULL;
}
 
/* Force the values of the variable at position "pos" of type "type" of "set"
 * to be no smaller than "value".
 */
__isl_give isl_set *isl_set_lower_bound_val(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *value)
{
  isl_map *map;
 
  map = set_to_map(set);
  return set_from_map(isl_map_lower_bound_val(map, type, pos, value));
}
 
/* Force the values of the variable at position "pos" of type "type" of "map"
 * to be no greater than "value".
 */
__isl_give isl_map *isl_map_upper_bound_val(__isl_take isl_map *map,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *value)
{
  if (!value)
    goto error;
  if (!isl_val_is_int(value))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "expecting integer value", goto error);
  map = isl_map_upper_bound(map, type, pos, value->n);
  isl_val_free(value);
  return map;
error:
  isl_val_free(value);
  isl_map_free(map);
  return NULL;
}
 
/* Force the values of the variable at position "pos" of type "type" of "set"
 * to be no greater than "value".
 */
__isl_give isl_set *isl_set_upper_bound_val(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned pos, __isl_take isl_val *value)
{
  isl_map *map;
 
  map = set_to_map(set);
  return set_from_map(isl_map_upper_bound_val(map, type, pos, value));
}
 
/* If "mv" has an explicit domain, then intersect the domain of "map"
 * with this explicit domain.
 *
 * An isl_multi_val object never has an explicit domain,
 * so simply return "map".
 */
static __isl_give isl_map *isl_map_intersect_multi_val_explicit_domain(
  __isl_take isl_map *map, __isl_keep isl_multi_val *mv)
{
  return map;
}
 
#undef BASE
#define BASE  val
#include "isl_map_bound_templ.c"
 
/* Apply "map_bound" to "set" with the corresponding value in "bound"
 * for each set dimension, by treating the set as a map.
 */
static __isl_give isl_set *set_bound_multi_val(__isl_take isl_set *set,
  __isl_take isl_multi_val *bound,
  __isl_give isl_map *map_bound(__isl_take isl_map *map,
    unsigned pos, __isl_take isl_val *value))
{
  isl_map *map;
 
  map = set_to_map(set);
  return set_from_map(map_bound_multi_val(map, bound, map_bound));
}
 
#undef BASE
#define BASE  pw_aff
#include "isl_map_bound_templ.c"
 
/* Apply "map_bound" to "set" with the corresponding value in "bound"
 * for each set dimension, by converting the set and the bound
 * to objects living in a map space.
 */
static __isl_give isl_set *set_bound_multi_pw_aff(__isl_take isl_set *set,
  __isl_take isl_multi_pw_aff *bound,
  __isl_give isl_map *set_bound(__isl_take isl_map *map,
    unsigned pos, __isl_take TYPE *value))
{
  isl_map *map;
 
  map = isl_map_from_range(set);
  bound = isl_multi_pw_aff_from_range(bound);
  map = map_bound_multi_pw_aff(map, bound, set_bound);
  return isl_map_range(map);
}
 
/* Wrapper around isl_map_lower_bound_val for use in map_bound_multi_val,
 * setting a bound on the given output dimension.
 */
static __isl_give isl_map *map_lower_bound_val(__isl_take isl_map *map,
  unsigned pos, __isl_take isl_val *v)
{
  return isl_map_lower_bound_val(map, isl_dim_out, pos, v);
}
 
/* Force the values of the set dimensions of "set"
 * to be no smaller than the corresponding values in "lower".
 */
__isl_give isl_set *isl_set_lower_bound_multi_val(__isl_take isl_set *set,
  __isl_take isl_multi_val *lower)
{
  return set_bound_multi_val(set, lower, &map_lower_bound_val);
}
 
/* Wrapper around isl_map_upper_bound_val for use in map_bound_multi_val,
 * setting a bound on the given output dimension.
 */
static __isl_give isl_map *map_upper_bound_val(__isl_take isl_map *map,
  unsigned pos, __isl_take isl_val *v)
{
  return isl_map_upper_bound_val(map, isl_dim_out, pos, v);
}
 
/* Force the values of the set dimensions of "set"
 * to be no greater than the corresponding values in "upper".
 */
__isl_give isl_set *isl_set_upper_bound_multi_val(__isl_take isl_set *set,
  __isl_take isl_multi_val *upper)
{
  return set_bound_multi_val(set, upper, &map_upper_bound_val);
}
 
/* Force the symbolic constant expression "bound"
 * to satisfy the relation "order" with respect to
 * the output variable at position "pos" of "map".
 *
 * Create an affine expression representing the output variable
 * in terms of the range and
 * compare it using "order" to "bound" (defined on the domain).
 * The result is a relation between elements in domain and range that
 * can be intersected with "map".
 */
static __isl_give isl_map *map_bound_pw_aff(__isl_take isl_map *map,
  unsigned pos, __isl_take isl_pw_aff *bound,
  __isl_give isl_map *(*order)(__isl_take isl_pw_aff *pa1,
    __isl_take isl_pw_aff *pa2))
{
  isl_space *space;
  isl_local_space *ls;
  isl_pw_aff *var;
 
  space = isl_space_range(isl_map_get_space(map));
  ls = isl_local_space_from_space(space);
  var = isl_pw_aff_var_on_domain(ls, isl_dim_set, pos);
  map = isl_map_intersect(map, order(bound, var));
  return map;
}
 
/* Force the values of the output variable at position "pos" of "map"
 * to be no smaller than the symbolic constant expression "lower".
 */
static __isl_give isl_map *map_lower_bound_pw_aff(__isl_take isl_map *map,
  unsigned pos, __isl_take isl_pw_aff *lower)
{
  return map_bound_pw_aff(map, pos, lower, &isl_pw_aff_le_map);
}
 
/* Force the values of the output variable at position "pos" of "map"
 * to be no greater than the symbolic constant expression "upper".
 */
static __isl_give isl_map *map_upper_bound_pw_aff(__isl_take isl_map *map,
  unsigned pos, __isl_take isl_pw_aff *upper)
{
  return map_bound_pw_aff(map, pos, upper, &isl_pw_aff_ge_map);
}
 
/* Force the values of the set dimensions of "set"
 * to be no smaller than the corresponding constant symbolic expressions
 * in "lower".
 */
__isl_give isl_set *isl_set_lower_bound_multi_pw_aff(__isl_take isl_set *set,
  __isl_take isl_multi_pw_aff *lower)
{
  return set_bound_multi_pw_aff(set, lower, &map_lower_bound_pw_aff);
}
 
/* Force the values of the set dimensions of "set"
 * to be no greater than the corresponding constant symbolic expressions
 * in "upper".
 */
__isl_give isl_set *isl_set_upper_bound_multi_pw_aff(__isl_take isl_set *set,
  __isl_take isl_multi_pw_aff *upper)
{
  return set_bound_multi_pw_aff(set, upper, &map_upper_bound_pw_aff);
}
 
/* Force the values of the output dimensions of "map"
 * to be no smaller than the corresponding constant symbolic expressions
 * in "lower".
 */
__isl_give isl_map *isl_map_lower_bound_multi_pw_aff(__isl_take isl_map *map,
  __isl_take isl_multi_pw_aff *lower)
{
  return map_bound_multi_pw_aff(map, lower, &map_lower_bound_pw_aff);
}
 
/* Force the values of the output dimensions of "map"
 * to be no greater than the corresponding constant symbolic expressions
 * in "upper".
 */
__isl_give isl_map *isl_map_upper_bound_multi_pw_aff(__isl_take isl_map *map,
  __isl_take isl_multi_pw_aff *upper)
{
  return map_bound_multi_pw_aff(map, upper, &map_upper_bound_pw_aff);
}
 
/* Bound the given variable of "bset" from below (or above is "upper"
 * is set) to "value".
 */
static __isl_give isl_basic_set *isl_basic_set_bound(
  __isl_take isl_basic_set *bset, enum isl_dim_type type, unsigned pos,
  isl_int value, int upper)
{
  return bset_from_bmap(basic_map_bound(bset_to_bmap(bset),
            type, pos, value, upper));
}
 
/* Bound the given variable of "bset" from below (or above is "upper"
 * is set) to "value".
 */
static __isl_give isl_basic_set *isl_basic_set_bound_val(
  __isl_take isl_basic_set *bset, enum isl_dim_type type, unsigned pos,
  __isl_take isl_val *value, int upper)
{
  if (!value)
    goto error;
  if (!isl_val_is_int(value))
    isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
      "expecting integer value", goto error);
  bset = isl_basic_set_bound(bset, type, pos, value->n, upper);
  isl_val_free(value);
  return bset;
error:
  isl_val_free(value);
  isl_basic_set_free(bset);
  return NULL;
}
 
/* Bound the given variable of "bset" from below to "value".
 */
__isl_give isl_basic_set *isl_basic_set_lower_bound_val(
  __isl_take isl_basic_set *bset, enum isl_dim_type type, unsigned pos,
  __isl_take isl_val *value)
{
  return isl_basic_set_bound_val(bset, type, pos, value, 0);
}
 
/* Bound the given variable of "bset" from above to "value".
 */
__isl_give isl_basic_set *isl_basic_set_upper_bound_val(
  __isl_take isl_basic_set *bset, enum isl_dim_type type, unsigned pos,
  __isl_take isl_val *value)
{
  return isl_basic_set_bound_val(bset, type, pos, value, 1);
}
 
__isl_give isl_map *isl_map_reverse(__isl_take isl_map *map)
{
  return isl_map_transform(map, &isl_space_reverse,
          &isl_basic_map_reverse);
}
 
/* Given a map (A -> B) -> C, return the corresponding map (B -> A) -> C.
 */
__isl_give isl_map *isl_map_domain_reverse(__isl_take isl_map *map)
{
  return isl_map_transform(map, &isl_space_domain_reverse,
          &isl_basic_map_domain_reverse);
}
 
/* Given a map A -> (B -> C), return the corresponding map A -> (C -> B).
 */
__isl_give isl_map *isl_map_range_reverse(__isl_take isl_map *map)
{
  return isl_map_transform(map, &isl_space_range_reverse,
          &isl_basic_map_range_reverse);
}
 
/* Given a set (A -> B), return the corresponding set (B -> A).
 */
__isl_give isl_set *isl_set_wrapped_reverse(__isl_take isl_set *set)
{
  isl_map *map = set_to_map(set);
 
  map = isl_map_transform(map, &isl_space_wrapped_reverse,
          &isl_basic_map_set_reverse);
  return set_from_map(map);
}
 
#undef TYPE
#define TYPE  isl_pw_multi_aff
#undef SUFFIX
#define SUFFIX  _pw_multi_aff
#undef EMPTY
#define EMPTY isl_pw_multi_aff_empty
#undef ADD
#define ADD isl_pw_multi_aff_union_add
#include "isl_map_lexopt_templ.c"
 
/* Given a map "map", compute the lexicographically minimal
 * (or maximal) image element for each domain element in dom,
 * in the form of an isl_pw_multi_aff.
 * If "empty" is not NULL, then set *empty to those elements in dom that
 * do not have an image element.
 * If "flags" includes ISL_OPT_FULL, then "dom" is NULL and the optimum
 * should be computed over the domain of "map".  "empty" is also NULL
 * in this case.
 *
 * We first compute the lexicographically minimal or maximal element
 * in the first basic map.  This results in a partial solution "res"
 * and a subset "todo" of dom that still need to be handled.
 * We then consider each of the remaining maps in "map" and successively
 * update both "res" and "todo".
 * If "empty" is NULL, then the todo sets are not needed and therefore
 * also not computed.
 */
static __isl_give isl_pw_multi_aff *isl_map_partial_lexopt_aligned_pw_multi_aff(
  __isl_take isl_map *map, __isl_take isl_set *dom,
  __isl_give isl_set **empty, unsigned flags)
{
  int i;
  int full;
  isl_pw_multi_aff *res;
  isl_set *todo;
 
  full = ISL_FL_ISSET(flags, ISL_OPT_FULL);
  if (!map || (!full && !dom))
    goto error;
 
  if (isl_map_plain_is_empty(map)) {
    if (empty)
      *empty = dom;
    else
      isl_set_free(dom);
    return isl_pw_multi_aff_from_map(map);
  }
 
  res = basic_map_partial_lexopt_pw_multi_aff(
              isl_basic_map_copy(map->p[0]),
              isl_set_copy(dom), empty, flags);
 
  if (empty)
    todo = *empty;
  for (i = 1; i < map->n; ++i) {
    isl_pw_multi_aff *res_i;
 
    res_i = basic_map_partial_lexopt_pw_multi_aff(
              isl_basic_map_copy(map->p[i]),
              isl_set_copy(dom), empty, flags);
 
    if (ISL_FL_ISSET(flags, ISL_OPT_MAX))
      res = isl_pw_multi_aff_union_lexmax(res, res_i);
    else
      res = isl_pw_multi_aff_union_lexmin(res, res_i);
 
    if (empty)
      todo = isl_set_intersect(todo, *empty);
  }
 
  isl_set_free(dom);
  isl_map_free(map);
 
  if (empty)
    *empty = todo;
 
  return res;
error:
  if (empty)
    *empty = NULL;
  isl_set_free(dom);
  isl_map_free(map);
  return NULL;
}
 
#undef TYPE
#define TYPE  isl_map
#undef SUFFIX
#define SUFFIX
#undef EMPTY
#define EMPTY isl_map_empty
#undef ADD
#define ADD isl_map_union_disjoint
#include "isl_map_lexopt_templ.c"
 
/* Given a map "map", compute the lexicographically minimal
 * (or maximal) image element for each domain element in "dom",
 * in the form of an isl_map.
 * If "empty" is not NULL, then set *empty to those elements in "dom" that
 * do not have an image element.
 * If "flags" includes ISL_OPT_FULL, then "dom" is NULL and the optimum
 * should be computed over the domain of "map".  "empty" is also NULL
 * in this case.
 *
 * If the input consists of more than one disjunct, then first
 * compute the desired result in the form of an isl_pw_multi_aff and
 * then convert that into an isl_map.
 *
 * This function used to have an explicit implementation in terms
 * of isl_maps, but it would continually intersect the domains of
 * partial results with the complement of the domain of the next
 * partial solution, potentially leading to an explosion in the number
 * of disjuncts if there are several disjuncts in the input.
 * An even earlier implementation of this function would look for
 * better results in the domain of the partial result and for extra
 * results in the complement of this domain, which would lead to
 * even more splintering.
 */
static __isl_give isl_map *isl_map_partial_lexopt_aligned(
  __isl_take isl_map *map, __isl_take isl_set *dom,
  __isl_give isl_set **empty, unsigned flags)
{
  int full;
  struct isl_map *res;
  isl_pw_multi_aff *pma;
 
  full = ISL_FL_ISSET(flags, ISL_OPT_FULL);
  if (!map || (!full && !dom))
    goto error;
 
  if (isl_map_plain_is_empty(map)) {
    if (empty)
      *empty = dom;
    else
      isl_set_free(dom);
    return map;
  }
 
  if (map->n == 1) {
    res = basic_map_partial_lexopt(isl_basic_map_copy(map->p[0]),
            dom, empty, flags);
    isl_map_free(map);
    return res;
  }
 
  pma = isl_map_partial_lexopt_aligned_pw_multi_aff(map, dom, empty,
              flags);
  return isl_map_from_pw_multi_aff_internal(pma);
error:
  if (empty)
    *empty = NULL;
  isl_set_free(dom);
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_map *isl_map_partial_lexmax(
    __isl_take isl_map *map, __isl_take isl_set *dom,
    __isl_give isl_set **empty)
{
  return isl_map_partial_lexopt(map, dom, empty, ISL_OPT_MAX);
}
 
__isl_give isl_map *isl_map_partial_lexmin(
    __isl_take isl_map *map, __isl_take isl_set *dom,
    __isl_give isl_set **empty)
{
  return isl_map_partial_lexopt(map, dom, empty, 0);
}
 
__isl_give isl_set *isl_set_partial_lexmin(
    __isl_take isl_set *set, __isl_take isl_set *dom,
    __isl_give isl_set **empty)
{
  return set_from_map(isl_map_partial_lexmin(set_to_map(set),
                dom, empty));
}
 
__isl_give isl_set *isl_set_partial_lexmax(
    __isl_take isl_set *set, __isl_take isl_set *dom,
    __isl_give isl_set **empty)
{
  return set_from_map(isl_map_partial_lexmax(set_to_map(set),
                dom, empty));
}
 
/* Compute the lexicographic minimum (or maximum if "flags" includes
 * ISL_OPT_MAX) of "bset" over its parametric domain.
 */
__isl_give isl_set *isl_basic_set_lexopt(__isl_take isl_basic_set *bset,
  unsigned flags)
{
  return isl_basic_map_lexopt(bset, flags);
}
 
__isl_give isl_map *isl_basic_map_lexmax(__isl_take isl_basic_map *bmap)
{
  return isl_basic_map_lexopt(bmap, ISL_OPT_MAX);
}
 
__isl_give isl_set *isl_basic_set_lexmin(__isl_take isl_basic_set *bset)
{
  return set_from_map(isl_basic_map_lexmin(bset_to_bmap(bset)));
}
 
__isl_give isl_set *isl_basic_set_lexmax(__isl_take isl_basic_set *bset)
{
  return set_from_map(isl_basic_map_lexmax(bset_to_bmap(bset)));
}
 
/* Compute the lexicographic minimum of "bset" over its parametric domain
 * for the purpose of quantifier elimination.
 * That is, find an explicit representation for all the existentially
 * quantified variables in "bset" by computing their lexicographic
 * minimum.
 */
static __isl_give isl_set *isl_basic_set_lexmin_compute_divs(
  __isl_take isl_basic_set *bset)
{
  return isl_basic_set_lexopt(bset, ISL_OPT_QE);
}
 
/* Given a basic map with one output dimension, compute the minimum or
 * maximum of that dimension as an isl_pw_aff.
 *
 * Compute the optimum as a lexicographic optimum over the single
 * output dimension and extract the single isl_pw_aff from the result.
 */
static __isl_give isl_pw_aff *basic_map_dim_opt(__isl_keep isl_basic_map *bmap,
  int max)
{
  isl_pw_multi_aff *pma;
  isl_pw_aff *pwaff;
 
  bmap = isl_basic_map_copy(bmap);
  pma = isl_basic_map_lexopt_pw_multi_aff(bmap, max ? ISL_OPT_MAX : 0);
  pwaff = isl_pw_multi_aff_get_pw_aff(pma, 0);
  isl_pw_multi_aff_free(pma);
 
  return pwaff;
}
 
/* Compute the minimum or maximum of the given output dimension
 * as a function of the parameters and the input dimensions,
 * but independently of the other output dimensions.
 *
 * We first project out the other output dimension and then compute
 * the "lexicographic" maximum in each basic map, combining the results
 * using isl_pw_aff_union_max.
 */
static __isl_give isl_pw_aff *map_dim_opt(__isl_take isl_map *map, int pos,
  int max)
{
  int i;
  isl_pw_aff *pwaff;
  isl_size n_out;
 
  n_out = isl_map_dim(map, isl_dim_out);
  if (n_out < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_out, pos + 1, n_out - (pos + 1));
  map = isl_map_project_out(map, isl_dim_out, 0, pos);
  if (!map)
    return NULL;
 
  if (map->n == 0) {
    isl_space *space = isl_map_get_space(map);
    isl_map_free(map);
    return isl_pw_aff_empty(space);
  }
 
  pwaff = basic_map_dim_opt(map->p[0], max);
  for (i = 1; i < map->n; ++i) {
    isl_pw_aff *pwaff_i;
 
    pwaff_i = basic_map_dim_opt(map->p[i], max);
    pwaff = isl_pw_aff_union_opt(pwaff, pwaff_i, max);
  }
 
  isl_map_free(map);
 
  return pwaff;
}
 
/* Compute the minimum of the given output dimension as a function of the
 * parameters and input dimensions, but independently of
 * the other output dimensions.
 */
__isl_give isl_pw_aff *isl_map_dim_min(__isl_take isl_map *map, int pos)
{
  return map_dim_opt(map, pos, 0);
}
 
/* Compute the maximum of the given output dimension as a function of the
 * parameters and input dimensions, but independently of
 * the other output dimensions.
 */
__isl_give isl_pw_aff *isl_map_dim_max(__isl_take isl_map *map, int pos)
{
  return map_dim_opt(map, pos, 1);
}
 
/* Compute the minimum or maximum of the given set dimension
 * as a function of the parameters,
 * but independently of the other set dimensions.
 */
static __isl_give isl_pw_aff *set_dim_opt(__isl_take isl_set *set, int pos,
  int max)
{
  return map_dim_opt(set, pos, max);
}
 
/* Compute the maximum of the given set dimension as a function of the
 * parameters, but independently of the other set dimensions.
 */
__isl_give isl_pw_aff *isl_set_dim_max(__isl_take isl_set *set, int pos)
{
  return set_dim_opt(set, pos, 1);
}
 
/* Compute the minimum of the given set dimension as a function of the
 * parameters, but independently of the other set dimensions.
 */
__isl_give isl_pw_aff *isl_set_dim_min(__isl_take isl_set *set, int pos)
{
  return set_dim_opt(set, pos, 0);
}
 
/* Apply a preimage specified by "mat" on the parameters of "bset".
 * bset is assumed to have only parameters and divs.
 */
static __isl_give isl_basic_set *basic_set_parameter_preimage(
  __isl_take isl_basic_set *bset, __isl_take isl_mat *mat)
{
  isl_size nparam;
 
  nparam = isl_basic_set_dim(bset, isl_dim_param);
  if (nparam < 0 || !mat)
    goto error;
 
  bset->dim = isl_space_cow(bset->dim);
  if (!bset->dim)
    goto error;
 
  isl_assert(bset->ctx, mat->n_row == 1 + nparam, goto error);
 
  bset->dim->nparam = 0;
  bset->dim->n_out = nparam;
  bset = isl_basic_set_preimage(bset, mat);
  if (bset) {
    bset->dim->nparam = bset->dim->n_out;
    bset->dim->n_out = 0;
  }
  return bset;
error:
  isl_mat_free(mat);
  isl_basic_set_free(bset);
  return NULL;
}
 
/* Apply a preimage specified by "mat" on the parameters of "set".
 * set is assumed to have only parameters and divs.
 */
static __isl_give isl_set *set_parameter_preimage(__isl_take isl_set *set,
  __isl_take isl_mat *mat)
{
  isl_space *space;
  isl_size nparam;
 
  nparam = isl_set_dim(set, isl_dim_param);
  if (nparam < 0 || !mat)
    goto error;
 
  if (mat->n_row != 1 + nparam)
    isl_die(isl_set_get_ctx(set), isl_error_internal,
      "unexpected number of rows", goto error);
 
  space = isl_set_get_space(set);
  space = isl_space_move_dims(space, isl_dim_set, 0,
            isl_dim_param, 0, nparam);
  set = isl_set_reset_space(set, space);
  set = isl_set_preimage(set, mat);
  nparam = isl_set_dim(set, isl_dim_out);
  if (nparam < 0)
    set = isl_set_free(set);
  space = isl_set_get_space(set);
  space = isl_space_move_dims(space, isl_dim_param, 0,
            isl_dim_out, 0, nparam);
  set = isl_set_reset_space(set, space);
  return set;
error:
  isl_mat_free(mat);
  isl_set_free(set);
  return NULL;
}
 
/* Intersect the basic set "bset" with the affine space specified by the
 * equalities in "eq".
 */
static __isl_give isl_basic_set *basic_set_append_equalities(
  __isl_take isl_basic_set *bset, __isl_take isl_mat *eq)
{
  int i, k;
  unsigned len;
 
  if (!bset || !eq)
    goto error;
 
  bset = isl_basic_set_extend(bset, 0, eq->n_row, 0);
  if (!bset)
    goto error;
 
  len = isl_basic_set_offset(bset, isl_dim_div) + bset->extra;
  for (i = 0; i < eq->n_row; ++i) {
    k = isl_basic_set_alloc_equality(bset);
    if (k < 0)
      goto error;
    isl_seq_cpy(bset->eq[k], eq->row[i], eq->n_col);
    isl_seq_clr(bset->eq[k] + eq->n_col, len - eq->n_col);
  }
  isl_mat_free(eq);
 
  bset = isl_basic_set_gauss(bset, NULL);
  bset = isl_basic_set_finalize(bset);
 
  return bset;
error:
  isl_mat_free(eq);
  isl_basic_set_free(bset);
  return NULL;
}
 
/* Intersect the set "set" with the affine space specified by the
 * equalities in "eq".
 */
static __isl_give isl_set *set_append_equalities(__isl_take isl_set *set,
  __isl_take isl_mat *eq)
{
  int i;
 
  if (!set || !eq)
    goto error;
 
  for (i = 0; i < set->n; ++i) {
    set->p[i] = basic_set_append_equalities(set->p[i],
          isl_mat_copy(eq));
    if (!set->p[i])
      goto error;
  }
  isl_mat_free(eq);
  return set;
error:
  isl_mat_free(eq);
  isl_set_free(set);
  return NULL;
}
 
/* Given a basic set "bset" that only involves parameters and existentially
 * quantified variables, return the index of the first equality
 * that only involves parameters.  If there is no such equality then
 * return bset->n_eq.
 *
 * This function assumes that isl_basic_set_gauss has been called on "bset".
 */
static int first_parameter_equality(__isl_keep isl_basic_set *bset)
{
  int i, j;
  isl_size nparam, n_div;
 
  nparam = isl_basic_set_dim(bset, isl_dim_param);
  n_div = isl_basic_set_dim(bset, isl_dim_div);
  if (nparam < 0 || n_div < 0)
    return -1;
 
  for (i = 0, j = n_div - 1; i < bset->n_eq && j >= 0; --j) {
    if (!isl_int_is_zero(bset->eq[i][1 + nparam + j]))
      ++i;
  }
 
  return i;
}
 
/* Compute an explicit representation for the existentially quantified
 * variables in "bset" by computing the "minimal value" of the set
 * variables.  Since there are no set variables, the computation of
 * the minimal value essentially computes an explicit representation
 * of the non-empty part(s) of "bset".
 *
 * The input only involves parameters and existentially quantified variables.
 * All equalities among parameters have been removed.
 *
 * Since the existentially quantified variables in the result are in general
 * going to be different from those in the input, we first replace
 * them by the minimal number of variables based on their equalities.
 * This should simplify the parametric integer programming.
 */
static __isl_give isl_set *base_compute_divs(__isl_take isl_basic_set *bset)
{
  isl_morph *morph1, *morph2;
  isl_set *set;
  isl_size n;
 
  if (!bset)
    return NULL;
  if (bset->n_eq == 0)
    return isl_basic_set_lexmin_compute_divs(bset);
 
  morph1 = isl_basic_set_parameter_compression(bset);
  bset = isl_morph_basic_set(isl_morph_copy(morph1), bset);
  bset = isl_basic_set_lift(bset);
  morph2 = isl_basic_set_variable_compression(bset, isl_dim_set);
  bset = isl_morph_basic_set(morph2, bset);
  n = isl_basic_set_dim(bset, isl_dim_set);
  if (n < 0)
    bset = isl_basic_set_free(bset);
  bset = isl_basic_set_project_out(bset, isl_dim_set, 0, n);
 
  set = isl_basic_set_lexmin_compute_divs(bset);
 
  set = isl_morph_set(isl_morph_inverse(morph1), set);
 
  return set;
}
 
/* Project the given basic set onto its parameter domain, possibly introducing
 * new, explicit, existential variables in the constraints.
 * The input has parameters and (possibly implicit) existential variables.
 * The output has the same parameters, but only
 * explicit existentially quantified variables.
 *
 * The actual projection is performed by pip, but pip doesn't seem
 * to like equalities very much, so we first remove the equalities
 * among the parameters by performing a variable compression on
 * the parameters.  Afterward, an inverse transformation is performed
 * and the equalities among the parameters are inserted back in.
 *
 * The variable compression on the parameters may uncover additional
 * equalities that were only implicit before.  We therefore check
 * if there are any new parameter equalities in the result and
 * if so recurse.  The removal of parameter equalities is required
 * for the parameter compression performed by base_compute_divs.
 */
static __isl_give isl_set *parameter_compute_divs(
  __isl_take isl_basic_set *bset)
{
  int i;
  struct isl_mat *eq;
  struct isl_mat *T, *T2;
  struct isl_set *set;
  isl_size nparam;
 
  bset = isl_basic_set_cow(bset);
  if (!bset)
    return NULL;
 
  if (bset->n_eq == 0)
    return base_compute_divs(bset);
 
  bset = isl_basic_set_gauss(bset, NULL);
  if (!bset)
    return NULL;
  if (isl_basic_set_plain_is_empty(bset))
    return isl_set_from_basic_set(bset);
 
  i = first_parameter_equality(bset);
  if (i == bset->n_eq)
    return base_compute_divs(bset);
 
  nparam = isl_basic_set_dim(bset, isl_dim_param);
  if (nparam < 0)
    return isl_set_from_basic_set(isl_basic_set_free(bset));
  eq = isl_mat_sub_alloc6(bset->ctx, bset->eq, i, bset->n_eq - i,
    0, 1 + nparam);
  eq = isl_mat_cow(eq);
  T = isl_mat_variable_compression(isl_mat_copy(eq), &T2);
  if (T && T->n_col == 0) {
    isl_mat_free(T);
    isl_mat_free(T2);
    isl_mat_free(eq);
    bset = isl_basic_set_set_to_empty(bset);
    return isl_set_from_basic_set(bset);
  }
  bset = basic_set_parameter_preimage(bset, T);
 
  i = first_parameter_equality(bset);
  if (!bset)
    set = NULL;
  else if (i == bset->n_eq)
    set = base_compute_divs(bset);
  else
    set = parameter_compute_divs(bset);
  set = set_parameter_preimage(set, T2);
  set = set_append_equalities(set, eq);
  return set;
}
 
/* Insert the divs from "ls" before those of "bmap".
 *
 * The number of columns is not changed, which means that the last
 * dimensions of "bmap" are being reintepreted as the divs from "ls".
 * The caller is responsible for removing the same number of dimensions
 * from the space of "bmap".
 */
static __isl_give isl_basic_map *insert_divs_from_local_space(
  __isl_take isl_basic_map *bmap, __isl_keep isl_local_space *ls)
{
  int i;
  isl_size n_div;
  int old_n_div;
 
  n_div = isl_local_space_dim(ls, isl_dim_div);
  if (n_div < 0)
    return isl_basic_map_free(bmap);
  if (n_div == 0)
    return bmap;
 
  old_n_div = bmap->n_div;
  bmap = insert_div_rows(bmap, n_div);
  if (!bmap)
    return NULL;
 
  for (i = 0; i < n_div; ++i) {
    isl_seq_cpy(bmap->div[i], ls->div->row[i], ls->div->n_col);
    isl_seq_clr(bmap->div[i] + ls->div->n_col, old_n_div);
  }
 
  return bmap;
}
 
/* Replace the space of "bmap" by the space and divs of "ls".
 *
 * If "ls" has any divs, then we simplify the result since we may
 * have discovered some additional equalities that could simplify
 * the div expressions.
 */
static __isl_give isl_basic_map *basic_replace_space_by_local_space(
  __isl_take isl_basic_map *bmap, __isl_take isl_local_space *ls)
{
  isl_size n_div;
 
  bmap = isl_basic_map_cow(bmap);
  n_div = isl_local_space_dim(ls, isl_dim_div);
  if (!bmap || n_div < 0)
    goto error;
 
  bmap = insert_divs_from_local_space(bmap, ls);
  if (!bmap)
    goto error;
 
  isl_space_free(bmap->dim);
  bmap->dim = isl_local_space_get_space(ls);
  if (!bmap->dim)
    goto error;
 
  isl_local_space_free(ls);
  if (n_div > 0)
    bmap = isl_basic_map_simplify(bmap);
  bmap = isl_basic_map_finalize(bmap);
  return bmap;
error:
  isl_basic_map_free(bmap);
  isl_local_space_free(ls);
  return NULL;
}
 
/* Replace the space of "map" by the space and divs of "ls".
 */
static __isl_give isl_map *replace_space_by_local_space(__isl_take isl_map *map,
  __isl_take isl_local_space *ls)
{
  int i;
 
  map = isl_map_cow(map);
  if (!map || !ls)
    goto error;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = basic_replace_space_by_local_space(map->p[i],
                isl_local_space_copy(ls));
    if (!map->p[i])
      goto error;
  }
  isl_space_free(isl_map_take_space(map));
  map = isl_map_restore_space(map, isl_local_space_get_space(ls));
 
  isl_local_space_free(ls);
  return map;
error:
  isl_local_space_free(ls);
  isl_map_free(map);
  return NULL;
}
 
/* Compute an explicit representation for the existentially
 * quantified variables for which do not know any explicit representation yet.
 *
 * We first sort the existentially quantified variables so that the
 * existentially quantified variables for which we already have an explicit
 * representation are placed before those for which we do not.
 * The input dimensions, the output dimensions and the existentially
 * quantified variables for which we already have an explicit
 * representation are then turned into parameters.
 * compute_divs returns a map with the same parameters and
 * no input or output dimensions and the dimension specification
 * is reset to that of the input, including the existentially quantified
 * variables for which we already had an explicit representation.
 */
static __isl_give isl_map *compute_divs(__isl_take isl_basic_map *bmap)
{
  struct isl_basic_set *bset;
  struct isl_set *set;
  struct isl_map *map;
  isl_space *space;
  isl_local_space *ls;
  isl_size nparam;
  isl_size n_in;
  isl_size n_out;
  int n_known;
  int i;
 
  bmap = isl_basic_map_sort_divs(bmap);
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
 
  n_known = isl_basic_map_first_unknown_div(bmap);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n_in = isl_basic_map_dim(bmap, isl_dim_in);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (n_known < 0 || nparam < 0 || n_in < 0 || n_out < 0)
    return isl_map_from_basic_map(isl_basic_map_free(bmap));
 
  space = isl_space_set_alloc(bmap->ctx,
            nparam + n_in + n_out + n_known, 0);
  if (!space)
    goto error;
 
  ls = isl_basic_map_get_local_space(bmap);
  ls = isl_local_space_drop_dims(ls, isl_dim_div,
          n_known, bmap->n_div - n_known);
  if (n_known > 0) {
    for (i = n_known; i < bmap->n_div; ++i)
      swap_div(bmap, i - n_known, i);
    bmap->n_div -= n_known;
    bmap->extra -= n_known;
  }
  bmap = isl_basic_map_reset_space(bmap, space);
  bset = bset_from_bmap(bmap);
 
  set = parameter_compute_divs(bset);
  map = set_to_map(set);
  map = replace_space_by_local_space(map, ls);
 
  return map;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Is the integer division at position "div" of "bmap" integral?
 * That is, does it have denominator 1?
 */
isl_bool isl_basic_map_div_is_integral(__isl_keep isl_basic_map *bmap, int div)
{
  if (isl_basic_map_check_range(bmap, isl_dim_div, div, 1) < 0)
    return isl_bool_error;
  return isl_int_is_one(bmap->div[div][0]);
}
 
/* Remove the explicit representation of local variable "div",
 * if there is any.
 */
__isl_give isl_basic_map *isl_basic_map_mark_div_unknown(
  __isl_take isl_basic_map *bmap, int div)
{
  isl_bool unknown;
 
  unknown = isl_basic_map_div_is_marked_unknown(bmap, div);
  if (unknown < 0)
    return isl_basic_map_free(bmap);
  if (unknown)
    return bmap;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
  isl_int_set_si(bmap->div[div][0], 0);
  return bmap;
}
 
/* Is local variable "div" of "bmap" marked as not having an explicit
 * representation?
 * Note that even if "div" is not marked in this way and therefore
 * has an explicit representation, this representation may still
 * depend (indirectly) on other local variables that do not
 * have an explicit representation.
 */
isl_bool isl_basic_map_div_is_marked_unknown(__isl_keep isl_basic_map *bmap,
  int div)
{
  if (isl_basic_map_check_range(bmap, isl_dim_div, div, 1) < 0)
    return isl_bool_error;
  return isl_int_is_zero(bmap->div[div][0]);
}
 
/* Return the position of the first local variable that does not
 * have an explicit representation.
 * Return the total number of local variables if they all have
 * an explicit representation.
 * Return -1 on error.
 */
int isl_basic_map_first_unknown_div(__isl_keep isl_basic_map *bmap)
{
  int i;
 
  if (!bmap)
    return -1;
 
  for (i = 0; i < bmap->n_div; ++i) {
    if (!isl_basic_map_div_is_known(bmap, i))
      return i;
  }
  return bmap->n_div;
}
 
/* Return the position of the first local variable that does not
 * have an explicit representation.
 * Return the total number of local variables if they all have
 * an explicit representation.
 * Return -1 on error.
 */
int isl_basic_set_first_unknown_div(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_first_unknown_div(bset);
}
 
/* Does "bmap" have an explicit representation for all local variables?
 */
isl_bool isl_basic_map_divs_known(__isl_keep isl_basic_map *bmap)
{
  int first;
  isl_size n;
 
  n = isl_basic_map_dim(bmap, isl_dim_div);
  first = isl_basic_map_first_unknown_div(bmap);
  if (n < 0 || first < 0)
    return isl_bool_error;
  return first == n;
}
 
/* Do all basic maps in "map" have an explicit representation
 * for all local variables?
 */
isl_bool isl_map_divs_known(__isl_keep isl_map *map)
{
  int i;
 
  if (!map)
    return isl_bool_error;
 
  for (i = 0; i < map->n; ++i) {
    int known = isl_basic_map_divs_known(map->p[i]);
    if (known <= 0)
      return known;
  }
 
  return isl_bool_true;
}
 
/* If bmap contains any unknown divs, then compute explicit
 * expressions for them.  However, this computation may be
 * quite expensive, so first try to remove divs that aren't
 * strictly needed.
 */
__isl_give isl_map *isl_basic_map_compute_divs(__isl_take isl_basic_map *bmap)
{
  int known;
  struct isl_map *map;
 
  known = isl_basic_map_divs_known(bmap);
  if (known < 0)
    goto error;
  if (known)
    return isl_map_from_basic_map(bmap);
 
  bmap = isl_basic_map_drop_redundant_divs(bmap);
 
  known = isl_basic_map_divs_known(bmap);
  if (known < 0)
    goto error;
  if (known)
    return isl_map_from_basic_map(bmap);
 
  map = compute_divs(bmap);
  return map;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_map *isl_map_compute_divs(__isl_take isl_map *map)
{
  int i;
  int known;
  struct isl_map *res;
 
  if (!map)
    return NULL;
  if (map->n == 0)
    return map;
 
  known = isl_map_divs_known(map);
  if (known < 0) {
    isl_map_free(map);
    return NULL;
  }
  if (known)
    return map;
 
  res = isl_basic_map_compute_divs(isl_basic_map_copy(map->p[0]));
  for (i = 1 ; i < map->n; ++i) {
    struct isl_map *r2;
    r2 = isl_basic_map_compute_divs(isl_basic_map_copy(map->p[i]));
    if (ISL_F_ISSET(map, ISL_MAP_DISJOINT))
      res = isl_map_union_disjoint(res, r2);
    else
      res = isl_map_union(res, r2);
  }
  isl_map_free(map);
 
  return res;
}
 
__isl_give isl_set *isl_basic_set_compute_divs(__isl_take isl_basic_set *bset)
{
  return set_from_map(isl_basic_map_compute_divs(bset_to_bmap(bset)));
}
 
__isl_give isl_set *isl_set_compute_divs(__isl_take isl_set *set)
{
  return set_from_map(isl_map_compute_divs(set_to_map(set)));
}
 
__isl_give isl_set *isl_map_domain(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size n_out;
 
  n_out = isl_map_dim(map, isl_dim_out);
  if (n_out < 0)
    return set_from_map(isl_map_free(map));
  space = isl_space_domain(isl_map_get_space(map));
 
  map = isl_map_project_out(map, isl_dim_out, 0, n_out);
 
  return set_from_map(isl_map_reset_space(map, space));
}
 
/* Return the union of "map1" and "map2", where we assume for now that
 * "map1" and "map2" are disjoint.  Note that the basic maps inside
 * "map1" or "map2" may not be disjoint from each other.
 * Also note that this function is also called from isl_map_union,
 * which takes care of handling the situation where "map1" and "map2"
 * may not be disjoint.
 *
 * If one of the inputs is empty, we can simply return the other input.
 * Similarly, if one of the inputs is universal, then it is equal to the union.
 */
static __isl_give isl_map *map_union_disjoint(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  int i;
  unsigned flags = 0;
  struct isl_map *map = NULL;
  int is_universe;
 
  if (isl_map_check_equal_space(map1, map2) < 0)
    goto error;
 
  if (map1->n == 0) {
    isl_map_free(map1);
    return map2;
  }
  if (map2->n == 0) {
    isl_map_free(map2);
    return map1;
  }
 
  is_universe = isl_map_plain_is_universe(map1);
  if (is_universe < 0)
    goto error;
  if (is_universe) {
    isl_map_free(map2);
    return map1;
  }
 
  is_universe = isl_map_plain_is_universe(map2);
  if (is_universe < 0)
    goto error;
  if (is_universe) {
    isl_map_free(map1);
    return map2;
  }
 
  if (ISL_F_ISSET(map1, ISL_MAP_DISJOINT) &&
      ISL_F_ISSET(map2, ISL_MAP_DISJOINT))
    ISL_FL_SET(flags, ISL_MAP_DISJOINT);
 
  map = isl_map_alloc_space(isl_space_copy(map1->dim),
        map1->n + map2->n, flags);
  if (!map)
    goto error;
  for (i = 0; i < map1->n; ++i) {
    map = isl_map_add_basic_map(map,
          isl_basic_map_copy(map1->p[i]));
    if (!map)
      goto error;
  }
  for (i = 0; i < map2->n; ++i) {
    map = isl_map_add_basic_map(map,
          isl_basic_map_copy(map2->p[i]));
    if (!map)
      goto error;
  }
  isl_map_free(map1);
  isl_map_free(map2);
  return map;
error:
  isl_map_free(map);
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
/* Return the union of "map1" and "map2", where "map1" and "map2" are
 * guaranteed to be disjoint by the caller.
 *
 * Note that this functions is called from within isl_map_make_disjoint,
 * so we have to be careful not to touch the constraints of the inputs
 * in any way.
 */
__isl_give isl_map *isl_map_union_disjoint(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map_align_params_bin(&map1, &map2);
  return map_union_disjoint(map1, map2);
}
 
/* Return the union of "map1" and "map2", where "map1" and "map2" may
 * not be disjoint.
 *
 * We currently simply call map_union_disjoint, the internal operation
 * of which does not really depend on the inputs being disjoint.
 * If the result contains more than one basic map, then we clear
 * the disjoint flag since the result may contain basic maps from
 * both inputs and these are not guaranteed to be disjoint.
 *
 * As a special case, if "map1" and "map2" are obviously equal,
 * then we simply return "map1".
 */
__isl_give isl_map *isl_map_union(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  int equal;
 
  if (isl_map_align_params_bin(&map1, &map2) < 0)
    goto error;
 
  equal = isl_map_plain_is_equal(map1, map2);
  if (equal < 0)
    goto error;
  if (equal) {
    isl_map_free(map2);
    return map1;
  }
 
  map1 = map_union_disjoint(map1, map2);
  if (!map1)
    return NULL;
  if (map1->n > 1)
    ISL_F_CLR(map1, ISL_MAP_DISJOINT);
  return map1;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
__isl_give isl_set *isl_set_union_disjoint(
  __isl_take isl_set *set1, __isl_take isl_set *set2)
{
  return set_from_map(isl_map_union_disjoint(set_to_map(set1),
                set_to_map(set2)));
}
 
__isl_give isl_set *isl_set_union(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  return set_from_map(isl_map_union(set_to_map(set1), set_to_map(set2)));
}
 
/* Apply "fn" to pairs of elements from "map" and "set" and collect
 * the results in a map living in "space".
 *
 * "map" and "set" are assumed to be compatible and non-NULL.
 */
static __isl_give isl_map *map_intersect_set(__isl_take isl_map *map,
  __isl_take isl_space *space, __isl_take isl_set *set,
  __isl_give isl_basic_map *fn(__isl_take isl_basic_map *bmap,
    __isl_take isl_basic_set *bset))
{
  unsigned flags = 0;
  struct isl_map *result;
  int i, j;
 
  if (isl_set_plain_is_universe(set)) {
    isl_set_free(set);
    return isl_map_reset_equal_dim_space(map, space);
  }
 
  if (ISL_F_ISSET(map, ISL_MAP_DISJOINT) &&
      ISL_F_ISSET(set, ISL_MAP_DISJOINT))
    ISL_FL_SET(flags, ISL_MAP_DISJOINT);
 
  result = isl_map_alloc_space(space, map->n * set->n, flags);
  for (i = 0; result && i < map->n; ++i)
    for (j = 0; j < set->n; ++j) {
      result = isl_map_add_basic_map(result,
          fn(isl_basic_map_copy(map->p[i]),
              isl_basic_set_copy(set->p[j])));
      if (!result)
        break;
    }
 
  isl_map_free(map);
  isl_set_free(set);
  return result;
}
 
__isl_give isl_map *isl_map_intersect_range(__isl_take isl_map *map,
  __isl_take isl_set *set)
{
  isl_bool ok;
  isl_space *space;
 
  isl_map_align_params_set(&map, &set);
  ok = isl_map_compatible_range(map, set);
  if (ok < 0)
    goto error;
  if (!ok)
    isl_die(set->ctx, isl_error_invalid,
      "incompatible spaces", goto error);
 
  space = isl_map_get_space(map);
  return map_intersect_set(map, space, set,
        &isl_basic_map_intersect_range);
error:
  isl_map_free(map);
  isl_set_free(set);
  return NULL;
}
 
/* Intersect the domain of "map" with "set".
 *
 * If the domain dimensions of "map" do not have any identifiers,
 * then copy them over from "set".
 */
__isl_give isl_map *isl_map_intersect_domain(__isl_take isl_map *map,
  __isl_take isl_set *set)
{
  isl_bool ok;
  isl_space *space;
 
  isl_map_align_params_set(&map, &set);
  ok = isl_map_compatible_domain(map, set);
  if (ok < 0)
    goto error;
  if (!ok)
    isl_die(set->ctx, isl_error_invalid,
      "incompatible spaces", goto error);
 
  space = isl_map_get_space(map);
  space = isl_space_copy_ids_if_unset(space, isl_dim_in,
          isl_set_peek_space(set), isl_dim_set);
  return map_intersect_set(map, space, set,
        &isl_basic_map_intersect_domain);
error:
  isl_map_free(map);
  isl_set_free(set);
  return NULL;
}
 
#undef BASE
#define BASE map
static
#include "isl_copy_tuple_id_templ.c"
 
/* Data structure that specifies how isl_map_intersect_factor
 * should operate.
 *
 * "preserve_type" is the tuple where the factor differs from
 * the input map and of which the identifiers needs
 * to be preserved explicitly.
 * "other_factor" is used to extract the space of the other factor
 * from the space of the product ("map").
 * "product" is used to combine the given factor and a universe map
 * in the space returned by "other_factor" to produce a map
 * that lives in the same space as the input map.
 */
struct isl_intersect_factor_control {
  enum isl_dim_type preserve_type;
  __isl_give isl_space *(*other_factor)(__isl_take isl_space *space);
  __isl_give isl_map *(*product)(__isl_take isl_map *factor,
    __isl_take isl_map *other);
};
 
/* Given a map "map" in some product space and a map "factor"
 * living in some factor space, return the intersection.
 *
 * After aligning the parameters,
 * the map "factor" is first extended to a map living in the same space
 * as "map" and then a regular intersection is computed.
 *
 * Note that the extension is computed as a product, which is anonymous
 * by default.  If "map" has an identifier on the corresponding tuple,
 * then this identifier needs to be set on the product
 * before the intersection is computed.
 */
static __isl_give isl_map *isl_map_intersect_factor(
  __isl_take isl_map *map, __isl_take isl_map *factor,
  struct isl_intersect_factor_control *control)
{
  isl_bool equal;
  isl_space *space;
  isl_map *other, *product;
 
  equal = isl_map_has_equal_params(map, factor);
  if (equal < 0)
    goto error;
  if (!equal) {
    map = isl_map_align_params(map, isl_map_get_space(factor));
    factor = isl_map_align_params(factor, isl_map_get_space(map));
  }
 
  space = isl_map_get_space(map);
  other = isl_map_universe(control->other_factor(space));
  product = control->product(factor, other);
 
  space = isl_map_peek_space(map);
  product = isl_map_copy_tuple_id(product, control->preserve_type,
          space, control->preserve_type);
  return map_intersect(map, product);
error:
  isl_map_free(map);
  isl_map_free(factor);
  return NULL;
}
 
/* Return the domain product of "map2" and "map1".
 */
static __isl_give isl_map *isl_map_reverse_domain_product(
  __isl_take isl_map *map1, __isl_take isl_map *map2)
{
  return isl_map_domain_product(map2, map1);
}
 
/* Return the range product of "map2" and "map1".
 */
static __isl_give isl_map *isl_map_reverse_range_product(
  __isl_take isl_map *map1, __isl_take isl_map *map2)
{
  return isl_map_range_product(map2, map1);
}
 
/* Given a map "map" in a space [A -> B] -> C and a map "factor"
 * in the space A -> C, return the intersection.
 */
__isl_give isl_map *isl_map_intersect_domain_factor_domain(
  __isl_take isl_map *map, __isl_take isl_map *factor)
{
  struct isl_intersect_factor_control control = {
    .preserve_type = isl_dim_in,
    .other_factor = isl_space_domain_factor_range,
    .product = isl_map_domain_product,
  };
 
  return isl_map_intersect_factor(map, factor, &control);
}
 
/* Given a map "map" in a space [A -> B] -> C and a map "factor"
 * in the space B -> C, return the intersection.
 */
__isl_give isl_map *isl_map_intersect_domain_factor_range(
  __isl_take isl_map *map, __isl_take isl_map *factor)
{
  struct isl_intersect_factor_control control = {
    .preserve_type = isl_dim_in,
    .other_factor = isl_space_domain_factor_domain,
    .product = isl_map_reverse_domain_product,
  };
 
  return isl_map_intersect_factor(map, factor, &control);
}
 
/* Given a map "map" in a space A -> [B -> C] and a map "factor"
 * in the space A -> B, return the intersection.
 */
__isl_give isl_map *isl_map_intersect_range_factor_domain(
  __isl_take isl_map *map, __isl_take isl_map *factor)
{
  struct isl_intersect_factor_control control = {
    .preserve_type = isl_dim_out,
    .other_factor = isl_space_range_factor_range,
    .product = isl_map_range_product,
  };
 
  return isl_map_intersect_factor(map, factor, &control);
}
 
/* Given a map "map" in a space A -> [B -> C] and a map "factor"
 * in the space A -> C, return the intersection.
 */
__isl_give isl_map *isl_map_intersect_range_factor_range(
  __isl_take isl_map *map, __isl_take isl_map *factor)
{
  struct isl_intersect_factor_control control = {
    .preserve_type = isl_dim_out,
    .other_factor = isl_space_range_factor_domain,
    .product = isl_map_reverse_range_product,
  };
 
  return isl_map_intersect_factor(map, factor, &control);
}
 
/* Given a set "set" in a space [A -> B] and a set "domain"
 * in the space A, return the intersection.
 *
 * The set "domain" is first extended to a set living in the space
 * [A -> B] and then a regular intersection is computed.
 */
__isl_give isl_set *isl_set_intersect_factor_domain(__isl_take isl_set *set,
  __isl_take isl_set *domain)
{
  struct isl_intersect_factor_control control = {
    .preserve_type = isl_dim_set,
    .other_factor = isl_space_factor_range,
    .product = isl_map_range_product,
  };
 
  return set_from_map(isl_map_intersect_factor(set_to_map(set),
            set_to_map(domain), &control));
}
 
/* Given a set "set" in a space [A -> B] and a set "range"
 * in the space B, return the intersection.
 *
 * The set "range" is first extended to a set living in the space
 * [A -> B] and then a regular intersection is computed.
 */
__isl_give isl_set *isl_set_intersect_factor_range(__isl_take isl_set *set,
  __isl_take isl_set *range)
{
  struct isl_intersect_factor_control control = {
    .preserve_type = isl_dim_set,
    .other_factor = isl_space_factor_domain,
    .product = isl_map_reverse_range_product,
  };
 
  return set_from_map(isl_map_intersect_factor(set_to_map(set),
            set_to_map(range), &control));
}
 
#undef BASE
#define BASE set
static
#include "isl_copy_tuple_id_templ.c"
 
/* Given a map "map" in a space [A -> B] -> C and a set "domain"
 * in the space A, return the intersection.
 *
 * The set "domain" is extended to a set living in the space [A -> B] and
 * the domain of "map" is intersected with this set.
 *
 * If "map" has an identifier on the domain tuple,
 * then this identifier needs to be set on this product
 * before the intersection is computed.
 */
__isl_give isl_map *isl_map_intersect_domain_wrapped_domain(
  __isl_take isl_map *map, __isl_take isl_set *domain)
{
  isl_space *space;
  isl_set *factor;
 
  isl_map_align_params_set(&map, &domain);
  space = isl_map_get_space(map);
  space = isl_space_domain_wrapped_range(space);
  factor = isl_set_universe(space);
  domain = isl_set_product(domain, factor);
  space = isl_map_peek_space(map);
  domain = isl_set_copy_tuple_id(domain, isl_dim_set, space, isl_dim_in);
  return isl_map_intersect_domain(map, domain);
}
 
/* Given a map "map" in a space A -> [B -> C] and a set "domain"
 * in the space B, return the intersection.
 *
 * The set "domain" is extended to a set living in the space [B -> C] and
 * the range of "map" is intersected with this set.
 *
 * If "map" has an identifier on the range tuple,
 * then this identifier needs to be set on this product
 * before the intersection is computed.
 */
__isl_give isl_map *isl_map_intersect_range_wrapped_domain(
  __isl_take isl_map *map, __isl_take isl_set *domain)
{
  isl_space *space;
  isl_set *factor;
 
  isl_map_align_params_set(&map, &domain);
  space = isl_map_get_space(map);
  space = isl_space_range_wrapped_range(space);
  factor = isl_set_universe(space);
  domain = isl_set_product(domain, factor);
  space = isl_map_peek_space(map);
  domain = isl_set_copy_tuple_id(domain, isl_dim_set, space, isl_dim_out);
  return isl_map_intersect_range(map, domain);
}
 
__isl_give isl_map *isl_map_apply_domain(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  if (isl_map_align_params_bin(&map1, &map2) < 0)
    goto error;
  map1 = isl_map_reverse(map1);
  map1 = isl_map_apply_range(map1, map2);
  return isl_map_reverse(map1);
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
__isl_give isl_map *isl_map_apply_range(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_space *space;
  struct isl_map *result;
  int i, j;
 
  if (isl_map_align_params_bin(&map1, &map2) < 0)
    goto error;
 
  space = isl_space_join(isl_space_copy(map1->dim),
          isl_space_copy(map2->dim));
 
  result = isl_map_alloc_space(space, map1->n * map2->n, 0);
  if (!result)
    goto error;
  for (i = 0; i < map1->n; ++i)
    for (j = 0; j < map2->n; ++j) {
      result = isl_map_add_basic_map(result,
          isl_basic_map_apply_range(
        isl_basic_map_copy(map1->p[i]),
        isl_basic_map_copy(map2->p[j])));
      if (!result)
        goto error;
    }
  isl_map_free(map1);
  isl_map_free(map2);
  if (result && result->n <= 1)
    ISL_F_SET(result, ISL_MAP_DISJOINT);
  return result;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
/* Is "bmap" a transformation, i.e.,
 * does it relate elements from the same space.
 */
isl_bool isl_basic_map_is_transformation(__isl_keep isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_peek_space(bmap);
  return isl_space_tuple_is_equal(space, isl_dim_in, space, isl_dim_out);
}
 
/* Check that "bmap" is a transformation, i.e.,
 * that it relates elements from the same space.
 */
static isl_stat isl_basic_map_check_transformation(
  __isl_keep isl_basic_map *bmap)
{
  isl_bool equal;
 
  equal = isl_basic_map_is_transformation(bmap);
  if (equal < 0)
    return isl_stat_error;
  if (!equal)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "domain and range don't match", return isl_stat_error);
  return isl_stat_ok;
}
 
/*
 * returns range - domain
 */
__isl_give isl_basic_set *isl_basic_map_deltas(__isl_take isl_basic_map *bmap)
{
  isl_space *target_space;
  struct isl_basic_set *bset;
  isl_size dim;
  isl_size nparam;
  isl_size total;
  int i;
 
  if (isl_basic_map_check_transformation(bmap) < 0)
    return isl_basic_map_free(bmap);
  dim = isl_basic_map_dim(bmap, isl_dim_in);
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  if (dim < 0 || nparam < 0)
    goto error;
  target_space = isl_space_domain(isl_basic_map_get_space(bmap));
  bmap = isl_basic_map_from_range(isl_basic_map_wrap(bmap));
  bmap = isl_basic_map_add_dims(bmap, isl_dim_in, dim);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    bmap = isl_basic_map_free(bmap);
  bmap = isl_basic_map_extend_constraints(bmap, dim, 0);
  for (i = 0; i < dim; ++i) {
    int j = isl_basic_map_alloc_equality(bmap);
    if (j < 0) {
      bmap = isl_basic_map_free(bmap);
      break;
    }
    isl_seq_clr(bmap->eq[j], 1 + total);
    isl_int_set_si(bmap->eq[j][1+nparam+i], 1);
    isl_int_set_si(bmap->eq[j][1+nparam+dim+i], 1);
    isl_int_set_si(bmap->eq[j][1+nparam+2*dim+i], -1);
  }
  bset = isl_basic_map_domain(bmap);
  bset = isl_basic_set_reset_space(bset, target_space);
  return bset;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Is the tuple of type "type1" of "map" the same as
 * the tuple of type "type2" of "space"?
 */
isl_bool isl_map_space_tuple_is_equal(__isl_keep isl_map *map,
  enum isl_dim_type type1, __isl_keep isl_space *space,
  enum isl_dim_type type2)
{
  isl_space *map_space;
 
  map_space = isl_map_peek_space(map);
  return isl_space_tuple_is_equal(map_space, type1, space, type2);
}
 
/* Is the tuple of type "type1" of "map1" the same as
 * the tuple of type "type2" of "map2"?
 */
isl_bool isl_map_tuple_is_equal(__isl_keep isl_map *map1,
  enum isl_dim_type type1, __isl_keep isl_map *map2,
  enum isl_dim_type type2)
{
  isl_space *space1, *space2;
 
  space1 = isl_map_peek_space(map1);
  space2 = isl_map_peek_space(map2);
  return isl_space_tuple_is_equal(space1, type1, space2, type2);
}
 
/* Is the space of "obj" equal to "space", ignoring parameters?
 */
isl_bool isl_map_has_space_tuples(__isl_keep isl_map *map,
  __isl_keep isl_space *space)
{
  isl_space *map_space;
 
  map_space = isl_map_peek_space(map);
  return isl_space_has_equal_tuples(map_space, space);
}
 
/* Check that "map" is a transformation, i.e.,
 * that it relates elements from the same space.
 */
isl_stat isl_map_check_transformation(__isl_keep isl_map *map)
{
  isl_bool equal;
 
  equal = isl_map_tuple_is_equal(map, isl_dim_in, map, isl_dim_out);
  if (equal < 0)
    return isl_stat_error;
  if (!equal)
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "domain and range don't match", return isl_stat_error);
  return isl_stat_ok;
}
 
/*
 * returns range - domain
 */
__isl_give isl_set *isl_map_deltas(__isl_take isl_map *map)
{
  int i;
  isl_space *space;
  struct isl_set *result;
 
  if (isl_map_check_transformation(map) < 0)
    goto error;
  space = isl_map_get_space(map);
  space = isl_space_domain(space);
  result = isl_set_alloc_space(space, map->n, 0);
  if (!result)
    goto error;
  for (i = 0; i < map->n; ++i)
    result = isl_set_add_basic_set(result,
        isl_basic_map_deltas(isl_basic_map_copy(map->p[i])));
  isl_map_free(map);
  return result;
error:
  isl_map_free(map);
  return NULL;
}
 
/*
 * returns [domain -> range] -> range - domain
 */
__isl_give isl_basic_map *isl_basic_map_deltas_map(
  __isl_take isl_basic_map *bmap)
{
  int i, k;
  isl_space *space;
  isl_basic_map *domain;
  isl_size nparam, n;
  isl_size total;
 
  if (isl_basic_map_check_transformation(bmap) < 0)
    return isl_basic_map_free(bmap);
 
  nparam = isl_basic_map_dim(bmap, isl_dim_param);
  n = isl_basic_map_dim(bmap, isl_dim_in);
  if (nparam < 0 || n < 0)
    return isl_basic_map_free(bmap);
 
  space = isl_basic_map_get_space(bmap);
  space = isl_space_from_range(isl_space_domain(space));
  domain = isl_basic_map_universe(space);
 
  bmap = isl_basic_map_from_domain(isl_basic_map_wrap(bmap));
  bmap = isl_basic_map_apply_range(bmap, domain);
  bmap = isl_basic_map_extend_constraints(bmap, n, 0);
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
 
  for (i = 0; i < n; ++i) {
    k = isl_basic_map_alloc_equality(bmap);
    if (k < 0)
      goto error;
    isl_seq_clr(bmap->eq[k], 1 + total);
    isl_int_set_si(bmap->eq[k][1 + nparam + i], 1);
    isl_int_set_si(bmap->eq[k][1 + nparam + n + i], -1);
    isl_int_set_si(bmap->eq[k][1 + nparam + n + n + i], 1);
  }
 
  bmap = isl_basic_map_gauss(bmap, NULL);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/*
 * returns [domain -> range] -> range - domain
 */
__isl_give isl_map *isl_map_deltas_map(__isl_take isl_map *map)
{
  if (isl_map_check_transformation(map) < 0)
    return isl_map_free(map);
 
  return isl_map_transform(map, &isl_space_range_map,
          &isl_basic_map_deltas_map);
}
 
/* Return pairs of elements { x -> y } such that y - x is in "deltas".
 */
__isl_give isl_map *isl_set_translation(__isl_take isl_set *deltas)
{
  isl_space *space;
  isl_map *map;
 
  space = isl_space_map_from_set(isl_set_get_space(deltas));
  map = isl_map_deltas_map(isl_map_universe(space));
  map = isl_map_intersect_range(map, deltas);
 
  return isl_set_unwrap(isl_map_domain(map));
}
 
__isl_give isl_basic_map *isl_basic_map_identity(__isl_take isl_space *space)
{
  isl_size n_in, n_out;
 
  n_in = isl_space_dim(space, isl_dim_in);
  n_out = isl_space_dim(space, isl_dim_out);
  if (n_in < 0 || n_out < 0)
    goto error;
  if (n_in != n_out)
    isl_die(space->ctx, isl_error_invalid,
      "number of input and output dimensions needs to be "
      "the same", goto error);
  return isl_basic_map_equal(space, n_in);
error:
  isl_space_free(space);
  return NULL;
}
 
__isl_give isl_map *isl_map_identity(__isl_take isl_space *space)
{
  return isl_map_from_basic_map(isl_basic_map_identity(space));
}
 
__isl_give isl_map *isl_set_identity(__isl_take isl_set *set)
{
  isl_space *space = isl_set_get_space(set);
  isl_map *id;
  id = isl_map_identity(isl_space_map_from_set(space));
  return isl_map_intersect_range(id, set);
}
 
/* Construct a basic set with all set dimensions having only non-negative
 * values.
 */
__isl_give isl_basic_set *isl_basic_set_positive_orthant(
  __isl_take isl_space *space)
{
  int i;
  isl_size nparam;
  isl_size dim;
  isl_size total;
  struct isl_basic_set *bset;
 
  nparam = isl_space_dim(space, isl_dim_param);
  dim = isl_space_dim(space, isl_dim_set);
  total = isl_space_dim(space, isl_dim_all);
  if (nparam < 0 || dim < 0 || total < 0)
    space = isl_space_free(space);
  bset = isl_basic_set_alloc_space(space, 0, 0, dim);
  if (!bset)
    return NULL;
  for (i = 0; i < dim; ++i) {
    int k = isl_basic_set_alloc_inequality(bset);
    if (k < 0)
      goto error;
    isl_seq_clr(bset->ineq[k], 1 + total);
    isl_int_set_si(bset->ineq[k][1 + nparam + i], 1);
  }
  return bset;
error:
  isl_basic_set_free(bset);
  return NULL;
}
 
/* Construct the half-space x_pos >= 0.
 */
static __isl_give isl_basic_set *nonneg_halfspace(__isl_take isl_space *space,
  int pos)
{
  int k;
  isl_size total;
  isl_basic_set *nonneg;
 
  total = isl_space_dim(space, isl_dim_all);
  if (total < 0)
    space = isl_space_free(space);
  nonneg = isl_basic_set_alloc_space(space, 0, 0, 1);
  k = isl_basic_set_alloc_inequality(nonneg);
  if (k < 0)
    goto error;
  isl_seq_clr(nonneg->ineq[k], 1 + total);
  isl_int_set_si(nonneg->ineq[k][pos], 1);
 
  return isl_basic_set_finalize(nonneg);
error:
  isl_basic_set_free(nonneg);
  return NULL;
}
 
/* Construct the half-space x_pos <= -1.
 */
static __isl_give isl_basic_set *neg_halfspace(__isl_take isl_space *space,
  int pos)
{
  int k;
  isl_size total;
  isl_basic_set *neg;
 
  total = isl_space_dim(space, isl_dim_all);
  if (total < 0)
    space = isl_space_free(space);
  neg = isl_basic_set_alloc_space(space, 0, 0, 1);
  k = isl_basic_set_alloc_inequality(neg);
  if (k < 0)
    goto error;
  isl_seq_clr(neg->ineq[k], 1 + total);
  isl_int_set_si(neg->ineq[k][0], -1);
  isl_int_set_si(neg->ineq[k][pos], -1);
 
  return isl_basic_set_finalize(neg);
error:
  isl_basic_set_free(neg);
  return NULL;
}
 
__isl_give isl_set *isl_set_split_dims(__isl_take isl_set *set,
  enum isl_dim_type type, unsigned first, unsigned n)
{
  int i;
  unsigned offset;
  isl_basic_set *nonneg;
  isl_basic_set *neg;
 
  if (n == 0)
    return set;
 
  if (isl_set_check_range(set, type, first, n) < 0)
    return isl_set_free(set);
 
  offset = pos(set->dim, type);
  for (i = 0; i < n; ++i) {
    nonneg = nonneg_halfspace(isl_set_get_space(set),
            offset + first + i);
    neg = neg_halfspace(isl_set_get_space(set), offset + first + i);
 
    set = isl_set_intersect(set, isl_basic_set_union(nonneg, neg));
  }
 
  return set;
}
 
static isl_stat foreach_orthant(__isl_take isl_set *set, int *signs, int first,
  int len,
  isl_stat (*fn)(__isl_take isl_set *orthant, int *signs, void *user),
  void *user)
{
  isl_set *half;
 
  if (!set)
    return isl_stat_error;
  if (isl_set_plain_is_empty(set)) {
    isl_set_free(set);
    return isl_stat_ok;
  }
  if (first == len)
    return fn(set, signs, user);
 
  signs[first] = 1;
  half = isl_set_from_basic_set(nonneg_halfspace(isl_set_get_space(set),
              1 + first));
  half = isl_set_intersect(half, isl_set_copy(set));
  if (foreach_orthant(half, signs, first + 1, len, fn, user) < 0)
    goto error;
 
  signs[first] = -1;
  half = isl_set_from_basic_set(neg_halfspace(isl_set_get_space(set),
              1 + first));
  half = isl_set_intersect(half, set);
  return foreach_orthant(half, signs, first + 1, len, fn, user);
error:
  isl_set_free(set);
  return isl_stat_error;
}
 
/* Call "fn" on the intersections of "set" with each of the orthants
 * (except for obviously empty intersections).  The orthant is identified
 * by the signs array, with each entry having value 1 or -1 according
 * to the sign of the corresponding variable.
 */
isl_stat isl_set_foreach_orthant(__isl_keep isl_set *set,
  isl_stat (*fn)(__isl_take isl_set *orthant, int *signs, void *user),
  void *user)
{
  isl_size nparam;
  isl_size nvar;
  int *signs;
  isl_stat r;
 
  if (!set)
    return isl_stat_error;
  if (isl_set_plain_is_empty(set))
    return isl_stat_ok;
 
  nparam = isl_set_dim(set, isl_dim_param);
  nvar = isl_set_dim(set, isl_dim_set);
  if (nparam < 0 || nvar < 0)
    return isl_stat_error;
 
  signs = isl_alloc_array(set->ctx, int, nparam + nvar);
 
  r = foreach_orthant(isl_set_copy(set), signs, 0, nparam + nvar,
          fn, user);
 
  free(signs);
 
  return r;
}
 
isl_bool isl_set_is_equal(__isl_keep isl_set *set1, __isl_keep isl_set *set2)
{
  return isl_map_is_equal(set_to_map(set1), set_to_map(set2));
}
 
isl_bool isl_basic_map_is_subset(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  isl_bool is_subset;
  struct isl_map *map1;
  struct isl_map *map2;
 
  if (!bmap1 || !bmap2)
    return isl_bool_error;
 
  map1 = isl_map_from_basic_map(isl_basic_map_copy(bmap1));
  map2 = isl_map_from_basic_map(isl_basic_map_copy(bmap2));
 
  is_subset = isl_map_is_subset(map1, map2);
 
  isl_map_free(map1);
  isl_map_free(map2);
 
  return is_subset;
}
 
isl_bool isl_basic_set_is_subset(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2)
{
  return isl_basic_map_is_subset(bset1, bset2);
}
 
isl_bool isl_basic_map_is_equal(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  isl_bool is_subset;
 
  if (!bmap1 || !bmap2)
    return isl_bool_error;
  is_subset = isl_basic_map_is_subset(bmap1, bmap2);
  if (is_subset != isl_bool_true)
    return is_subset;
  is_subset = isl_basic_map_is_subset(bmap2, bmap1);
  return is_subset;
}
 
isl_bool isl_basic_set_is_equal(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2)
{
  return isl_basic_map_is_equal(
    bset_to_bmap(bset1), bset_to_bmap(bset2));
}
 
isl_bool isl_map_is_empty(__isl_keep isl_map *map)
{
  int i;
  int is_empty;
 
  if (!map)
    return isl_bool_error;
  for (i = 0; i < map->n; ++i) {
    is_empty = isl_basic_map_is_empty(map->p[i]);
    if (is_empty < 0)
      return isl_bool_error;
    if (!is_empty)
      return isl_bool_false;
  }
  return isl_bool_true;
}
 
isl_bool isl_map_plain_is_empty(__isl_keep isl_map *map)
{
  return map ? map->n == 0 : isl_bool_error;
}
 
isl_bool isl_set_plain_is_empty(__isl_keep isl_set *set)
{
  return set ? set->n == 0 : isl_bool_error;
}
 
isl_bool isl_set_is_empty(__isl_keep isl_set *set)
{
  return isl_map_is_empty(set_to_map(set));
}
 
#undef TYPE
#define TYPE  isl_basic_map
 
static
#include "isl_type_has_equal_space_bin_templ.c"
#include "isl_type_check_equal_space_templ.c"
 
/* Check that "bset1" and "bset2" live in the same space,
 * reporting an error if they do not.
 */
isl_stat isl_basic_set_check_equal_space(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2)
{
  return isl_basic_map_check_equal_space(bset_to_bmap(bset1),
            bset_to_bmap(bset1));
}
 
#undef TYPE
#define TYPE  isl_map
 
#include "isl_type_has_equal_space_bin_templ.c"
#include "isl_type_check_equal_space_templ.c"
#include "isl_type_has_space_templ.c"
 
isl_bool isl_set_has_equal_space(__isl_keep isl_set *set1,
  __isl_keep isl_set *set2)
{
  return isl_map_has_equal_space(set_to_map(set1), set_to_map(set2));
}
 
#undef TYPE1
#define TYPE1   isl_map
#undef TYPE2
#define TYPE2   isl_basic_map
#undef TYPE_PAIR
#define TYPE_PAIR isl_map_basic_map
 
static
#include "isl_type_has_equal_space_templ.c"
#include "isl_type_check_equal_space_templ.c"
 
/* Check that "set" and "bset" live in the same space,
 * reporting an error if they do not.
 */
isl_stat isl_set_basic_set_check_equal_space(__isl_keep isl_set *set,
  __isl_keep isl_basic_set *bset)
{
  return isl_map_basic_map_check_equal_space(set_to_map(set),
                bset_to_bmap(bset));
}
 
static isl_bool map_is_equal(__isl_keep isl_map *map1, __isl_keep isl_map *map2)
{
  isl_bool is_subset;
 
  if (!map1 || !map2)
    return isl_bool_error;
  is_subset = isl_map_is_subset(map1, map2);
  if (is_subset != isl_bool_true)
    return is_subset;
  is_subset = isl_map_is_subset(map2, map1);
  return is_subset;
}
 
/* Is "map1" equal to "map2"?
 *
 * First check if they are obviously equal.
 * If not, then perform a more detailed analysis.
 */
isl_bool isl_map_is_equal(__isl_keep isl_map *map1, __isl_keep isl_map *map2)
{
  isl_bool equal;
 
  equal = isl_map_plain_is_equal(map1, map2);
  if (equal < 0 || equal)
    return equal;
  return isl_map_align_params_map_map_and_test(map1, map2, &map_is_equal);
}
 
isl_bool isl_basic_map_is_strict_subset(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  isl_bool is_subset;
 
  if (!bmap1 || !bmap2)
    return isl_bool_error;
  is_subset = isl_basic_map_is_subset(bmap1, bmap2);
  if (is_subset != isl_bool_true)
    return is_subset;
  is_subset = isl_basic_map_is_subset(bmap2, bmap1);
  return isl_bool_not(is_subset);
}
 
isl_bool isl_map_is_strict_subset(__isl_keep isl_map *map1,
  __isl_keep isl_map *map2)
{
  isl_bool is_subset;
 
  if (!map1 || !map2)
    return isl_bool_error;
  is_subset = isl_map_is_subset(map1, map2);
  if (is_subset != isl_bool_true)
    return is_subset;
  is_subset = isl_map_is_subset(map2, map1);
  return isl_bool_not(is_subset);
}
 
isl_bool isl_set_is_strict_subset(__isl_keep isl_set *set1,
  __isl_keep isl_set *set2)
{
  return isl_map_is_strict_subset(set_to_map(set1), set_to_map(set2));
}
 
/* Is "bmap" obviously equal to the universe with the same space?
 *
 * That is, does it not have any constraints?
 */
isl_bool isl_basic_map_plain_is_universe(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
  return bmap->n_eq == 0 && bmap->n_ineq == 0;
}
 
/* Is "bset" obviously equal to the universe with the same space?
 */
isl_bool isl_basic_set_plain_is_universe(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_plain_is_universe(bset);
}
 
/* If "c" does not involve any existentially quantified variables,
 * then set *univ to false and abort
 */
static isl_stat involves_divs(__isl_take isl_constraint *c, void *user)
{
  isl_bool *univ = user;
  isl_size n;
 
  n = isl_constraint_dim(c, isl_dim_div);
  if (n < 0)
    c = isl_constraint_free(c);
  *univ = isl_constraint_involves_dims(c, isl_dim_div, 0, n);
  isl_constraint_free(c);
  if (*univ < 0 || !*univ)
    return isl_stat_error;
  return isl_stat_ok;
}
 
/* Is "bmap" equal to the universe with the same space?
 *
 * First check if it is obviously equal to the universe.
 * If not and if there are any constraints not involving
 * existentially quantified variables, then it is certainly
 * not equal to the universe.
 * Otherwise, check if the universe is a subset of "bmap".
 */
isl_bool isl_basic_map_is_universe(__isl_keep isl_basic_map *bmap)
{
  isl_size n_div;
  isl_bool univ;
  isl_basic_map *test;
 
  univ = isl_basic_map_plain_is_universe(bmap);
  if (univ < 0 || univ)
    return univ;
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_div < 0)
    return isl_bool_error;
  if (n_div == 0)
    return isl_bool_false;
  univ = isl_bool_true;
  if (isl_basic_map_foreach_constraint(bmap, &involves_divs, &univ) < 0 &&
      univ)
    return isl_bool_error;
  if (univ < 0 || !univ)
    return univ;
  test = isl_basic_map_universe(isl_basic_map_get_space(bmap));
  univ = isl_basic_map_is_subset(test, bmap);
  isl_basic_map_free(test);
  return univ;
}
 
/* Is "bset" equal to the universe with the same space?
 */
isl_bool isl_basic_set_is_universe(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_is_universe(bset);
}
 
isl_bool isl_map_plain_is_universe(__isl_keep isl_map *map)
{
  int i;
 
  if (!map)
    return isl_bool_error;
 
  for (i = 0; i < map->n; ++i) {
    isl_bool r = isl_basic_map_plain_is_universe(map->p[i]);
    if (r < 0 || r)
      return r;
  }
 
  return isl_bool_false;
}
 
isl_bool isl_set_plain_is_universe(__isl_keep isl_set *set)
{
  return isl_map_plain_is_universe(set_to_map(set));
}
 
isl_bool isl_basic_map_is_empty(__isl_keep isl_basic_map *bmap)
{
  struct isl_basic_set *bset = NULL;
  struct isl_vec *sample = NULL;
  isl_bool empty, non_empty;
 
  if (!bmap)
    return isl_bool_error;
 
  if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
    return isl_bool_true;
 
  if (isl_basic_map_plain_is_universe(bmap))
    return isl_bool_false;
 
  if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL)) {
    struct isl_basic_map *copy = isl_basic_map_copy(bmap);
    copy = isl_basic_map_remove_redundancies(copy);
    empty = isl_basic_map_plain_is_empty(copy);
    isl_basic_map_free(copy);
    return empty;
  }
 
  non_empty = isl_basic_map_plain_is_non_empty(bmap);
  if (non_empty < 0)
    return isl_bool_error;
  if (non_empty)
    return isl_bool_false;
  isl_vec_free(bmap->sample);
  bmap->sample = NULL;
  bset = isl_basic_map_underlying_set(isl_basic_map_copy(bmap));
  if (!bset)
    return isl_bool_error;
  sample = isl_basic_set_sample_vec(bset);
  if (!sample)
    return isl_bool_error;
  empty = sample->size == 0;
  isl_vec_free(bmap->sample);
  bmap->sample = sample;
  if (empty)
    ISL_F_SET(bmap, ISL_BASIC_MAP_EMPTY);
 
  return empty;
}
 
isl_bool isl_basic_map_plain_is_empty(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
  return ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY);
}
 
isl_bool isl_basic_set_plain_is_empty(__isl_keep isl_basic_set *bset)
{
  if (!bset)
    return isl_bool_error;
  return ISL_F_ISSET(bset, ISL_BASIC_SET_EMPTY);
}
 
/* Is "bmap" known to be non-empty?
 *
 * That is, is the cached sample still valid?
 */
isl_bool isl_basic_map_plain_is_non_empty(__isl_keep isl_basic_map *bmap)
{
  isl_size total;
 
  if (!bmap)
    return isl_bool_error;
  if (!bmap->sample)
    return isl_bool_false;
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_bool_error;
  if (bmap->sample->size != 1 + total)
    return isl_bool_false;
  return isl_basic_map_contains(bmap, bmap->sample);
}
 
isl_bool isl_basic_set_is_empty(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_is_empty(bset_to_bmap(bset));
}
 
__isl_give isl_map *isl_basic_map_union(__isl_take isl_basic_map *bmap1,
  __isl_take isl_basic_map *bmap2)
{
  struct isl_map *map;
 
  if (isl_basic_map_check_equal_space(bmap1, bmap2) < 0)
    goto error;
 
  map = isl_map_alloc_space(isl_space_copy(bmap1->dim), 2, 0);
  if (!map)
    goto error;
  map = isl_map_add_basic_map(map, bmap1);
  map = isl_map_add_basic_map(map, bmap2);
  return map;
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_set *isl_basic_set_union(__isl_take isl_basic_set *bset1,
  __isl_take isl_basic_set *bset2)
{
  return set_from_map(isl_basic_map_union(bset_to_bmap(bset1),
            bset_to_bmap(bset2)));
}
 
/* Order divs such that any div only depends on previous divs */
__isl_give isl_basic_map *isl_basic_map_order_divs(
  __isl_take isl_basic_map *bmap)
{
  int i;
  isl_size off;
 
  off = isl_basic_map_var_offset(bmap, isl_dim_div);
  if (off < 0)
    return isl_basic_map_free(bmap);
 
  for (i = 0; i < bmap->n_div; ++i) {
    int pos;
    if (isl_int_is_zero(bmap->div[i][0]))
      continue;
    pos = isl_seq_first_non_zero(bmap->div[i]+1+1+off+i,
                  bmap->n_div-i);
    if (pos == -1)
      continue;
    if (pos == 0)
      isl_die(isl_basic_map_get_ctx(bmap), isl_error_internal,
        "integer division depends on itself",
        return isl_basic_map_free(bmap));
    bmap = isl_basic_map_swap_div(bmap, i, i + pos);
    if (!bmap)
      return NULL;
    --i;
  }
  return bmap;
}
 
__isl_give isl_map *isl_map_order_divs(__isl_take isl_map *map)
{
  int i;
 
  if (!map)
    return 0;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_order_divs(map->p[i]);
    if (!map->p[i])
      goto error;
  }
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
/* Sort the local variables of "bset".
 */
__isl_give isl_basic_set *isl_basic_set_sort_divs(
  __isl_take isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_sort_divs(bset_to_bmap(bset)));
}
 
/* Apply the expansion computed by isl_merge_divs.
 * The expansion itself is given by "exp" while the resulting
 * list of divs is given by "div".
 *
 * Move the integer divisions of "bmap" into the right position
 * according to "exp" and then introduce the additional integer
 * divisions, adding div constraints.
 * The moving should be done first to avoid moving coefficients
 * in the definitions of the extra integer divisions.
 */
__isl_give isl_basic_map *isl_basic_map_expand_divs(
  __isl_take isl_basic_map *bmap, __isl_take isl_mat *div, int *exp)
{
  int i, j;
  int n_div;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap || !div)
    goto error;
 
  if (div->n_row < bmap->n_div)
    isl_die(isl_mat_get_ctx(div), isl_error_invalid,
      "not an expansion", goto error);
 
  n_div = bmap->n_div;
  bmap = isl_basic_map_extend(bmap, div->n_row - n_div, 0,
              2 * (div->n_row - n_div));
 
  for (i = n_div; i < div->n_row; ++i)
    if (isl_basic_map_alloc_div(bmap) < 0)
      goto error;
 
  for (j = n_div - 1; j >= 0; --j) {
    if (exp[j] == j)
      break;
    bmap = isl_basic_map_swap_div(bmap, j, exp[j]);
    if (!bmap)
      goto error;
  }
  j = 0;
  for (i = 0; i < div->n_row; ++i) {
    if (j < n_div && exp[j] == i) {
      j++;
    } else {
      isl_seq_cpy(bmap->div[i], div->row[i], div->n_col);
      if (isl_basic_map_div_is_marked_unknown(bmap, i))
        continue;
      bmap = isl_basic_map_add_div_constraints(bmap, i);
      if (!bmap)
        goto error;
    }
  }
 
  isl_mat_free(div);
  return bmap;
error:
  isl_basic_map_free(bmap);
  isl_mat_free(div);
  return NULL;
}
 
/* Apply the expansion computed by isl_merge_divs.
 * The expansion itself is given by "exp" while the resulting
 * list of divs is given by "div".
 */
__isl_give isl_basic_set *isl_basic_set_expand_divs(
  __isl_take isl_basic_set *bset, __isl_take isl_mat *div, int *exp)
{
  return isl_basic_map_expand_divs(bset, div, exp);
}
 
/* Look for a div in dst that corresponds to the div "div" in src.
 * The divs before "div" in src and dst are assumed to be the same.
 * 
 * Return the position of the corresponding div in dst
 * if there is one.  Otherwise, return a position beyond the integer divisions.
 * Return isl_size_error on error.
 */
static isl_size find_div(__isl_keep isl_basic_map *dst,
  __isl_keep isl_basic_map *src, unsigned div)
{
  int i;
  isl_size n_div;
  isl_size v_div;
 
  v_div = isl_basic_map_var_offset(src, isl_dim_div);
  n_div = isl_basic_map_dim(dst, isl_dim_div);
  if (n_div < 0 || v_div < 0)
    return isl_size_error;
  isl_assert(dst->ctx, div <= n_div, return isl_size_error);
  for (i = div; i < n_div; ++i)
    if (isl_seq_eq(dst->div[i], src->div[div], 1+1+v_div+div) &&
        !isl_seq_any_non_zero(dst->div[i] + 1 + 1 + v_div + div,
            n_div - div))
      return i;
  return n_div;
}
 
/* Align the local variables of "dst" to those of "src",
 * adding local variables from "src" if needed.
 * That is, make sure that the first src->n_div local variables
 * of the result correspond to those of src.
 * For any integer division that is copied to "dst",
 * the defining constraints are also introduced to "dst".
 * For an existentially quantified variable (without an explicit definition)
 * only an unconstrained existentially quantified variable
 * in the same positions is introduced.
 * The integer division of "src" are assumed to be ordered.
 *
 * The integer divisions are swapped into the right position
 * (possibly after adding them first).  This may result
 * in the remaining integer divisions appearing in the wrong order,
 * i.e., with some integer division appearing before
 * some other integer division on which it depends.
 * The integer divisions therefore need to be ordered.
 * This will not affect the integer divisions aligned to those of "src",
 * since "src" is assumed to have ordered integer divisions.
 *
 * The result is not finalized as by design it will have redundant
 * divs if any divs from "src" were copied.
 */
__isl_give isl_basic_map *isl_basic_map_align_divs(
  __isl_take isl_basic_map *dst, __isl_keep isl_basic_map *src)
{
  int i;
  int extended;
  isl_size v_div;
  isl_size dst_n_div, src_n_div;
 
  src_n_div = isl_basic_map_dim(src, isl_dim_div);
  if (!dst || src_n_div < 0)
    return isl_basic_map_free(dst);
 
  if (src_n_div == 0)
    return dst;
 
  v_div = isl_basic_map_var_offset(src, isl_dim_div);
  if (v_div < 0)
    return isl_basic_map_free(dst);
 
  extended = 0;
  dst_n_div = isl_basic_map_dim(dst, isl_dim_div);
  if (dst_n_div < 0)
    dst = isl_basic_map_free(dst);
  for (i = 0; i < src_n_div; ++i) {
    isl_bool known;
    isl_size j;
 
    known = isl_basic_map_div_is_known(src, i);
    if (known < 0)
      return isl_basic_map_free(dst);
    j = known ? find_div(dst, src, i) : dst_n_div;
    if (j < 0)
      dst = isl_basic_map_free(dst);
    if (j == dst_n_div) {
      if (!extended) {
        int extra = src_n_div - i;
        dst = isl_basic_map_cow(dst);
        if (!dst)
          return isl_basic_map_free(dst);
        dst = isl_basic_map_extend(dst,
            extra, 0, 2 * extra);
        extended = 1;
      }
      j = isl_basic_map_alloc_div(dst);
      if (j < 0)
        return isl_basic_map_free(dst);
      dst_n_div++;
      if (!known)
        continue;
      isl_seq_cpy(dst->div[j], src->div[i], 1+1+v_div+i);
      isl_seq_clr(dst->div[j]+1+1+v_div+i, dst_n_div - i);
      dst = isl_basic_map_add_div_constraints(dst, j);
      if (!dst)
        return isl_basic_map_free(dst);
    }
    if (j != i)
      dst = isl_basic_map_swap_div(dst, i, j);
    if (!dst)
      return isl_basic_map_free(dst);
  }
  return isl_basic_map_order_divs(dst);
}
 
__isl_give isl_map *isl_map_align_divs_internal(__isl_take isl_map *map)
{
  int i;
 
  if (!map)
    return NULL;
  if (map->n == 0)
    return map;
  map = isl_map_compute_divs(map);
  map = isl_map_order_divs(map);
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 1; i < map->n; ++i)
    map->p[0] = isl_basic_map_align_divs(map->p[0], map->p[i]);
  for (i = 1; i < map->n; ++i) {
    map->p[i] = isl_basic_map_align_divs(map->p[i], map->p[0]);
    if (!map->p[i])
      return isl_map_free(map);
  }
 
  map = isl_map_unmark_normalized(map);
  return map;
}
 
__isl_give isl_map *isl_map_align_divs(__isl_take isl_map *map)
{
  return isl_map_align_divs_internal(map);
}
 
__isl_give isl_set *isl_set_align_divs(__isl_take isl_set *set)
{
  return set_from_map(isl_map_align_divs_internal(set_to_map(set)));
}
 
/* Align the divs of the basic maps in "map" to those
 * of the basic maps in "list", as well as to the other basic maps in "map".
 * The elements in "list" are assumed to have known divs.
 */
__isl_give isl_map *isl_map_align_divs_to_basic_map_list(
  __isl_take isl_map *map, __isl_keep isl_basic_map_list *list)
{
  int i;
  isl_size n;
 
  n = isl_basic_map_list_n_basic_map(list);
  map = isl_map_compute_divs(map);
  map = isl_map_cow(map);
  if (!map || n < 0)
    return isl_map_free(map);
  if (map->n == 0)
    return map;
 
  for (i = 0; i < n; ++i) {
    isl_basic_map *bmap;
 
    bmap = isl_basic_map_list_get_basic_map(list, i);
    bmap = isl_basic_map_order_divs(bmap);
    map->p[0] = isl_basic_map_align_divs(map->p[0], bmap);
    isl_basic_map_free(bmap);
  }
  if (!map->p[0])
    return isl_map_free(map);
 
  return isl_map_align_divs_internal(map);
}
 
/* Align the divs of each element of "list" to those of "bmap".
 * Both "bmap" and the elements of "list" are assumed to have known divs.
 */
__isl_give isl_basic_map_list *isl_basic_map_list_align_divs_to_basic_map(
  __isl_take isl_basic_map_list *list, __isl_keep isl_basic_map *bmap)
{
  int i;
  isl_size n;
 
  n = isl_basic_map_list_n_basic_map(list);
  if (n < 0 || !bmap)
    return isl_basic_map_list_free(list);
 
  for (i = 0; i < n; ++i) {
    isl_basic_map *bmap_i;
 
    bmap_i = isl_basic_map_list_get_basic_map(list, i);
    bmap_i = isl_basic_map_align_divs(bmap_i, bmap);
    list = isl_basic_map_list_set_basic_map(list, i, bmap_i);
  }
 
  return list;
}
 
__isl_give isl_set *isl_set_apply( __isl_take isl_set *set,
  __isl_take isl_map *map)
{
  isl_bool ok;
 
  isl_map_align_params_set(&map, &set);
  ok = isl_map_compatible_domain(map, set);
  if (ok < 0)
    goto error;
  if (!ok)
    isl_die(isl_set_get_ctx(set), isl_error_invalid,
      "incompatible spaces", goto error);
  map = isl_map_intersect_domain(map, set);
  set = isl_map_range(map);
  return set;
error:
  isl_set_free(set);
  isl_map_free(map);
  return NULL;
}
 
/* There is no need to cow as removing empty parts doesn't change
 * the meaning of the set.
 */
__isl_give isl_map *isl_map_remove_empty_parts(__isl_take isl_map *map)
{
  int i;
 
  if (!map)
    return NULL;
 
  for (i = map->n - 1; i >= 0; --i)
    map = remove_if_empty(map, i);
 
  return map;
}
 
__isl_give isl_set *isl_set_remove_empty_parts(__isl_take isl_set *set)
{
  return set_from_map(isl_map_remove_empty_parts(set_to_map(set)));
}
 
/* Create a binary relation that maps the shared initial "pos" dimensions
 * of "bset1" and "bset2" to the remaining dimensions of "bset1" and "bset2".
 */
static __isl_give isl_basic_map *join_initial(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2, int pos)
{
  isl_basic_map *bmap1;
  isl_basic_map *bmap2;
 
  bmap1 = isl_basic_map_from_range(isl_basic_set_copy(bset1));
  bmap2 = isl_basic_map_from_range(isl_basic_set_copy(bset2));
  bmap1 = isl_basic_map_move_dims(bmap1, isl_dim_in, 0,
          isl_dim_out, 0, pos);
  bmap2 = isl_basic_map_move_dims(bmap2, isl_dim_in, 0,
          isl_dim_out, 0, pos);
  return isl_basic_map_range_product(bmap1, bmap2);
}
 
/* Given two basic sets bset1 and bset2, compute the maximal difference
 * between the values of dimension pos in bset1 and those in bset2
 * for any common value of the parameters and dimensions preceding pos.
 */
static enum isl_lp_result basic_set_maximal_difference_at(
  __isl_keep isl_basic_set *bset1, __isl_keep isl_basic_set *bset2,
  int pos, isl_int *opt)
{
  isl_basic_map *bmap1;
  struct isl_ctx *ctx;
  struct isl_vec *obj;
  isl_size total;
  isl_size nparam;
  isl_size dim1;
  enum isl_lp_result res;
 
  nparam = isl_basic_set_dim(bset1, isl_dim_param);
  dim1 = isl_basic_set_dim(bset1, isl_dim_set);
  if (nparam < 0 || dim1 < 0 || !bset2)
    return isl_lp_error;
 
  bmap1 = join_initial(bset1, bset2, pos);
  total = isl_basic_map_dim(bmap1, isl_dim_all);
  if (total < 0)
    return isl_lp_error;
 
  ctx = bmap1->ctx;
  obj = isl_vec_alloc(ctx, 1 + total);
  if (!obj)
    goto error;
  isl_seq_clr(obj->block.data, 1 + total);
  isl_int_set_si(obj->block.data[1+nparam+pos], 1);
  isl_int_set_si(obj->block.data[1+nparam+pos+(dim1-pos)], -1);
  res = isl_basic_map_solve_lp(bmap1, 1, obj->block.data, ctx->one,
          opt, NULL, NULL);
  isl_basic_map_free(bmap1);
  isl_vec_free(obj);
  return res;
error:
  isl_basic_map_free(bmap1);
  return isl_lp_error;
}
 
/* Given two _disjoint_ basic sets bset1 and bset2, check whether
 * for any common value of the parameters and dimensions preceding pos
 * in both basic sets, the values of dimension pos in bset1 are
 * smaller or larger than those in bset2.
 *
 * Returns
 *   1 if bset1 follows bset2
 *  -1 if bset1 precedes bset2
 *   0 if bset1 and bset2 are incomparable
 *  -2 if some error occurred.
 */
int isl_basic_set_compare_at(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2, int pos)
{
  isl_int opt;
  enum isl_lp_result res;
  int cmp;
 
  isl_int_init(opt);
 
  res = basic_set_maximal_difference_at(bset1, bset2, pos, &opt);
 
  if (res == isl_lp_empty)
    cmp = 0;
  else if ((res == isl_lp_ok && isl_int_is_pos(opt)) ||
      res == isl_lp_unbounded)
    cmp = 1;
  else if (res == isl_lp_ok && isl_int_is_neg(opt))
    cmp = -1;
  else
    cmp = -2;
 
  isl_int_clear(opt);
  return cmp;
}
 
/* Given two basic sets bset1 and bset2, check whether
 * for any common value of the parameters and dimensions preceding pos
 * there is a value of dimension pos in bset1 that is larger
 * than a value of the same dimension in bset2.
 *
 * Return
 *   1 if there exists such a pair
 *   0 if there is no such pair, but there is a pair of equal values
 *  -1 otherwise
 *  -2 if some error occurred.
 */
int isl_basic_set_follows_at(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2, int pos)
{
  isl_bool empty;
  isl_basic_map *bmap;
  isl_size dim1;
 
  dim1 = isl_basic_set_dim(bset1, isl_dim_set);
  if (dim1 < 0)
    return -2;
  bmap = join_initial(bset1, bset2, pos);
  bmap = isl_basic_map_order_ge(bmap, isl_dim_out, 0,
              isl_dim_out, dim1 - pos);
  empty = isl_basic_map_is_empty(bmap);
  if (empty < 0)
    goto error;
  if (empty) {
    isl_basic_map_free(bmap);
    return -1;
  }
  bmap = isl_basic_map_order_gt(bmap, isl_dim_out, 0,
              isl_dim_out, dim1 - pos);
  empty = isl_basic_map_is_empty(bmap);
  if (empty < 0)
    goto error;
  isl_basic_map_free(bmap);
  if (empty)
    return 0;
  return 1;
error:
  isl_basic_map_free(bmap);
  return -2;
}
 
/* Given two sets set1 and set2, check whether
 * for any common value of the parameters and dimensions preceding pos
 * there is a value of dimension pos in set1 that is larger
 * than a value of the same dimension in set2.
 *
 * Return
 *   1 if there exists such a pair
 *   0 if there is no such pair, but there is a pair of equal values
 *  -1 otherwise
 *  -2 if some error occurred.
 */
int isl_set_follows_at(__isl_keep isl_set *set1,
  __isl_keep isl_set *set2, int pos)
{
  int i, j;
  int follows = -1;
 
  if (!set1 || !set2)
    return -2;
 
  for (i = 0; i < set1->n; ++i)
    for (j = 0; j < set2->n; ++j) {
      int f;
      f = isl_basic_set_follows_at(set1->p[i], set2->p[j], pos);
      if (f == 1 || f == -2)
        return f;
      if (f > follows)
        follows = f;
    }
 
  return follows;
}
 
static isl_bool isl_basic_map_plain_has_fixed_var(
  __isl_keep isl_basic_map *bmap, unsigned pos, isl_int *val)
{
  int i;
  int d;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_bool_error;
  for (i = 0, d = total-1; i < bmap->n_eq && d+1 > pos; ++i) {
    for (; d+1 > pos; --d)
      if (!isl_int_is_zero(bmap->eq[i][1+d]))
        break;
    if (d != pos)
      continue;
    if (isl_seq_any_non_zero(bmap->eq[i]+1, d))
      return isl_bool_false;
    if (isl_seq_any_non_zero(bmap->eq[i]+1+d+1, total-d-1))
      return isl_bool_false;
    if (!isl_int_is_one(bmap->eq[i][1+d]))
      return isl_bool_false;
    if (val)
      isl_int_neg(*val, bmap->eq[i][0]);
    return isl_bool_true;
  }
  return isl_bool_false;
}
 
static isl_bool isl_map_plain_has_fixed_var(__isl_keep isl_map *map,
  unsigned pos, isl_int *val)
{
  int i;
  isl_int v;
  isl_int tmp;
  isl_bool fixed;
 
  if (!map)
    return isl_bool_error;
  if (map->n == 0)
    return isl_bool_false;
  if (map->n == 1)
    return isl_basic_map_plain_has_fixed_var(map->p[0], pos, val); 
  isl_int_init(v);
  isl_int_init(tmp);
  fixed = isl_basic_map_plain_has_fixed_var(map->p[0], pos, &v); 
  for (i = 1; fixed == isl_bool_true && i < map->n; ++i) {
    fixed = isl_basic_map_plain_has_fixed_var(map->p[i], pos, &tmp); 
    if (fixed == isl_bool_true && isl_int_ne(tmp, v))
      fixed = isl_bool_false;
  }
  if (val)
    isl_int_set(*val, v);
  isl_int_clear(tmp);
  isl_int_clear(v);
  return fixed;
}
 
static isl_bool isl_basic_set_plain_has_fixed_var(
  __isl_keep isl_basic_set *bset, unsigned pos, isl_int *val)
{
  return isl_basic_map_plain_has_fixed_var(bset_to_bmap(bset),
            pos, val);
}
 
isl_bool isl_basic_map_plain_is_fixed(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, isl_int *val)
{
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    return isl_bool_error;
  return isl_basic_map_plain_has_fixed_var(bmap,
    isl_basic_map_offset(bmap, type) - 1 + pos, val);
}
 
/* If "bmap" obviously lies on a hyperplane where the given dimension
 * has a fixed value, then return that value.
 * Otherwise return NaN.
 */
__isl_give isl_val *isl_basic_map_plain_get_val_if_fixed(
  __isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos)
{
  isl_ctx *ctx;
  isl_val *v;
  isl_bool fixed;
 
  if (!bmap)
    return NULL;
  ctx = isl_basic_map_get_ctx(bmap);
  v = isl_val_alloc(ctx);
  if (!v)
    return NULL;
  fixed = isl_basic_map_plain_is_fixed(bmap, type, pos, &v->n);
  if (fixed < 0)
    return isl_val_free(v);
  if (fixed) {
    isl_int_set_si(v->d, 1);
    return v;
  }
  isl_val_free(v);
  return isl_val_nan(ctx);
}
 
isl_bool isl_map_plain_is_fixed(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos, isl_int *val)
{
  if (isl_map_check_range(map, type, pos, 1) < 0)
    return isl_bool_error;
  return isl_map_plain_has_fixed_var(map,
    map_offset(map, type) - 1 + pos, val);
}
 
/* If "map" obviously lies on a hyperplane where the given dimension
 * has a fixed value, then return that value.
 * Otherwise return NaN.
 */
__isl_give isl_val *isl_map_plain_get_val_if_fixed(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos)
{
  isl_ctx *ctx;
  isl_val *v;
  isl_bool fixed;
 
  if (!map)
    return NULL;
  ctx = isl_map_get_ctx(map);
  v = isl_val_alloc(ctx);
  if (!v)
    return NULL;
  fixed = isl_map_plain_is_fixed(map, type, pos, &v->n);
  if (fixed < 0)
    return isl_val_free(v);
  if (fixed) {
    isl_int_set_si(v->d, 1);
    return v;
  }
  isl_val_free(v);
  return isl_val_nan(ctx);
}
 
/* If "set" obviously lies on a hyperplane where the given dimension
 * has a fixed value, then return that value.
 * Otherwise return NaN.
 */
__isl_give isl_val *isl_set_plain_get_val_if_fixed(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return isl_map_plain_get_val_if_fixed(set, type, pos);
}
 
/* Return a sequence of values in the same space as "set"
 * that are equal to the corresponding set dimensions of "set"
 * for those set dimensions that obviously lie on a hyperplane
 * where the dimension has a fixed value.
 * The other elements are set to NaN.
 */
__isl_give isl_multi_val *isl_set_get_plain_multi_val_if_fixed(
  __isl_keep isl_set *set)
{
  int i;
  isl_size n;
  isl_space *space;
  isl_multi_val *mv;
 
  space = isl_space_drop_all_params(isl_set_get_space(set));
  mv = isl_multi_val_alloc(space);
  n = isl_multi_val_size(mv);
  if (n < 0)
    return isl_multi_val_free(mv);
 
  for (i = 0; i < n; ++i) {
    isl_val *v;
 
    v = isl_set_plain_get_val_if_fixed(set, isl_dim_set, i);
    mv = isl_multi_val_set_val(mv, i, v);
  }
 
  return mv;
}
 
/* Check if dimension dim has fixed value and if so and if val is not NULL,
 * then return this fixed value in *val.
 */
isl_bool isl_basic_set_plain_dim_is_fixed(__isl_keep isl_basic_set *bset,
  unsigned dim, isl_int *val)
{
  isl_size nparam;
 
  nparam = isl_basic_set_dim(bset, isl_dim_param);
  if (nparam < 0)
    return isl_bool_error;
  return isl_basic_set_plain_has_fixed_var(bset, nparam + dim, val);
}
 
/* Return -1 if the constraint "c1" should be sorted before "c2"
 * and 1 if it should be sorted after "c2".
 * Return 0 if the two constraints are the same (up to the constant term).
 *
 * In particular, if a constraint involves later variables than another
 * then it is sorted after this other constraint.
 * uset_gist depends on constraints without existentially quantified
 * variables sorting first.
 *
 * For constraints that have the same latest variable, those
 * with the same coefficient for this latest variable (first in absolute value
 * and then in actual value) are grouped together.
 * This is useful for detecting pairs of constraints that can
 * be chained in their printed representation.
 *
 * Finally, within a group, constraints are sorted according to
 * their coefficients (excluding the constant term).
 */
static int sort_constraint_cmp(const void *p1, const void *p2, void *arg)
{
  isl_int **c1 = (isl_int **) p1;
  isl_int **c2 = (isl_int **) p2;
  int l1, l2;
  unsigned size = *(unsigned *) arg;
  int cmp;
 
  l1 = isl_seq_last_non_zero(*c1 + 1, size);
  l2 = isl_seq_last_non_zero(*c2 + 1, size);
 
  if (l1 != l2)
    return l1 - l2;
 
  cmp = isl_int_abs_cmp((*c1)[1 + l1], (*c2)[1 + l1]);
  if (cmp != 0)
    return cmp;
  cmp = isl_int_cmp((*c1)[1 + l1], (*c2)[1 + l1]);
  if (cmp != 0)
    return -cmp;
 
  return isl_seq_cmp(*c1 + 1, *c2 + 1, size);
}
 
/* Return -1 if the constraint "c1" of "bmap" is sorted before "c2"
 * by isl_basic_map_sort_constraints, 1 if it is sorted after "c2"
 * and 0 if the two constraints are the same (up to the constant term).
 */
int isl_basic_map_constraint_cmp(__isl_keep isl_basic_map *bmap,
  isl_int *c1, isl_int *c2)
{
  isl_size total;
  unsigned size;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return -2;
  size = total;
  return sort_constraint_cmp(&c1, &c2, &size);
}
 
__isl_give isl_basic_map *isl_basic_map_sort_constraints(
  __isl_take isl_basic_map *bmap)
{
  isl_size total;
  unsigned size;
 
  if (!bmap)
    return NULL;
  if (bmap->n_ineq == 0)
    return bmap;
  if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_SORTED))
    return bmap;
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return isl_basic_map_free(bmap);
  size = total;
  if (isl_sort(bmap->ineq, bmap->n_ineq, sizeof(isl_int *),
        &sort_constraint_cmp, &size) < 0)
    return isl_basic_map_free(bmap);
  ISL_F_SET(bmap, ISL_BASIC_MAP_SORTED);
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_sort_constraints(
  __isl_take isl_basic_set *bset)
{
  isl_basic_map *bmap = bset_to_bmap(bset);
  return bset_from_bmap(isl_basic_map_sort_constraints(bmap));
}
 
__isl_give isl_basic_map *isl_basic_map_normalize(
  __isl_take isl_basic_map *bmap)
{
  bmap = isl_basic_map_remove_redundancies(bmap);
  bmap = isl_basic_map_sort_constraints(bmap);
  return bmap;
}
int isl_basic_map_plain_cmp(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  int i, cmp;
  isl_size total;
  isl_space *space1, *space2;
 
  if (!bmap1 || !bmap2)
    return -1;
 
  if (bmap1 == bmap2)
    return 0;
  space1 = isl_basic_map_peek_space(bmap1);
  space2 = isl_basic_map_peek_space(bmap2);
  cmp = isl_space_cmp(space1, space2);
  if (cmp)
    return cmp;
  if (ISL_F_ISSET(bmap1, ISL_BASIC_MAP_RATIONAL) !=
      ISL_F_ISSET(bmap2, ISL_BASIC_MAP_RATIONAL))
    return ISL_F_ISSET(bmap1, ISL_BASIC_MAP_RATIONAL) ? -1 : 1;
  if (ISL_F_ISSET(bmap1, ISL_BASIC_MAP_EMPTY) &&
      ISL_F_ISSET(bmap2, ISL_BASIC_MAP_EMPTY))
    return 0;
  if (ISL_F_ISSET(bmap1, ISL_BASIC_MAP_EMPTY))
    return 1;
  if (ISL_F_ISSET(bmap2, ISL_BASIC_MAP_EMPTY))
    return -1;
  if (bmap1->n_eq != bmap2->n_eq)
    return bmap1->n_eq - bmap2->n_eq;
  if (bmap1->n_ineq != bmap2->n_ineq)
    return bmap1->n_ineq - bmap2->n_ineq;
  if (bmap1->n_div != bmap2->n_div)
    return bmap1->n_div - bmap2->n_div;
  total = isl_basic_map_dim(bmap1, isl_dim_all);
  if (total < 0)
    return -1;
  for (i = 0; i < bmap1->n_eq; ++i) {
    cmp = isl_seq_cmp(bmap1->eq[i], bmap2->eq[i], 1+total);
    if (cmp)
      return cmp;
  }
  for (i = 0; i < bmap1->n_ineq; ++i) {
    cmp = isl_seq_cmp(bmap1->ineq[i], bmap2->ineq[i], 1+total);
    if (cmp)
      return cmp;
  }
  for (i = 0; i < bmap1->n_div; ++i) {
    isl_bool unknown1, unknown2;
 
    unknown1 = isl_basic_map_div_is_marked_unknown(bmap1, i);
    unknown2 = isl_basic_map_div_is_marked_unknown(bmap2, i);
    if (unknown1 < 0 || unknown2 < 0)
      return -1;
    if (unknown1 && unknown2)
      continue;
    if (unknown1)
      return 1;
    if (unknown2)
      return -1;
    cmp = isl_seq_cmp(bmap1->div[i], bmap2->div[i], 1+1+total);
    if (cmp)
      return cmp;
  }
  return 0;
}
 
int isl_basic_set_plain_cmp(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2)
{
  return isl_basic_map_plain_cmp(bset1, bset2);
}
 
int isl_set_plain_cmp(__isl_keep isl_set *set1, __isl_keep isl_set *set2)
{
  int i, cmp;
 
  if (set1 == set2)
    return 0;
  if (set1->n != set2->n)
    return set1->n - set2->n;
 
  for (i = 0; i < set1->n; ++i) {
    cmp = isl_basic_set_plain_cmp(set1->p[i], set2->p[i]);
    if (cmp)
      return cmp;
  }
 
  return 0;
}
 
isl_bool isl_basic_map_plain_is_equal(__isl_keep isl_basic_map *bmap1,
  __isl_keep isl_basic_map *bmap2)
{
  if (!bmap1 || !bmap2)
    return isl_bool_error;
  return isl_basic_map_plain_cmp(bmap1, bmap2) == 0;
}
 
isl_bool isl_basic_set_plain_is_equal(__isl_keep isl_basic_set *bset1,
  __isl_keep isl_basic_set *bset2)
{
  return isl_basic_map_plain_is_equal(bset_to_bmap(bset1),
              bset_to_bmap(bset2));
}
 
static int qsort_bmap_cmp(const void *p1, const void *p2)
{
  isl_basic_map *bmap1 = *(isl_basic_map **) p1;
  isl_basic_map *bmap2 = *(isl_basic_map **) p2;
 
  return isl_basic_map_plain_cmp(bmap1, bmap2);
}
 
/* Sort the basic maps of "map" and remove duplicate basic maps.
 *
 * While removing basic maps, we make sure that the basic maps remain
 * sorted because isl_map_normalize expects the basic maps of the result
 * to be sorted.
 */
static __isl_give isl_map *sort_and_remove_duplicates(__isl_take isl_map *map)
{
  int i, j;
 
  map = isl_map_remove_empty_parts(map);
  if (!map)
    return NULL;
  qsort(map->p, map->n, sizeof(struct isl_basic_map *), qsort_bmap_cmp);
  for (i = map->n - 1; i >= 1; --i) {
    if (!isl_basic_map_plain_is_equal(map->p[i - 1], map->p[i]))
      continue;
    isl_basic_map_free(map->p[i-1]);
    for (j = i; j < map->n; ++j)
      map->p[j - 1] = map->p[j];
    map->n--;
  }
 
  return map;
}
 
/* Remove obvious duplicates among the basic maps of "map".
 *
 * Unlike isl_map_normalize, this function does not remove redundant
 * constraints and only removes duplicates that have exactly the same
 * constraints in the input.  It does sort the constraints and
 * the basic maps to ease the detection of duplicates.
 *
 * If "map" has already been normalized or if the basic maps are
 * disjoint, then there can be no duplicates.
 */
__isl_give isl_map *isl_map_remove_obvious_duplicates(__isl_take isl_map *map)
{
  int i;
  isl_basic_map *bmap;
 
  if (!map)
    return NULL;
  if (map->n <= 1)
    return map;
  if (ISL_F_ISSET(map, ISL_MAP_NORMALIZED | ISL_MAP_DISJOINT))
    return map;
  for (i = 0; i < map->n; ++i) {
    bmap = isl_basic_map_copy(map->p[i]);
    bmap = isl_basic_map_sort_constraints(bmap);
    if (!bmap)
      return isl_map_free(map);
    isl_basic_map_free(map->p[i]);
    map->p[i] = bmap;
  }
 
  map = sort_and_remove_duplicates(map);
  return map;
}
 
/* We normalize in place, but if anything goes wrong we need
 * to return NULL, so we need to make sure we don't change the
 * meaning of any possible other copies of map.
 */
__isl_give isl_map *isl_map_normalize(__isl_take isl_map *map)
{
  int i;
  struct isl_basic_map *bmap;
 
  if (!map)
    return NULL;
  if (ISL_F_ISSET(map, ISL_MAP_NORMALIZED))
    return map;
  for (i = 0; i < map->n; ++i) {
    bmap = isl_basic_map_normalize(isl_basic_map_copy(map->p[i]));
    if (!bmap)
      goto error;
    isl_basic_map_free(map->p[i]);
    map->p[i] = bmap;
  }
 
  map = sort_and_remove_duplicates(map);
  if (map)
    ISL_F_SET(map, ISL_MAP_NORMALIZED);
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_normalize(__isl_take isl_set *set)
{
  return set_from_map(isl_map_normalize(set_to_map(set)));
}
 
isl_bool isl_map_plain_is_equal(__isl_keep isl_map *map1,
  __isl_keep isl_map *map2)
{
  int i;
  isl_bool equal;
 
  if (!map1 || !map2)
    return isl_bool_error;
 
  if (map1 == map2)
    return isl_bool_true;
  equal = isl_map_has_equal_space(map1, map2);
  if (equal < 0 || !equal)
    return equal;
 
  map1 = isl_map_copy(map1);
  map2 = isl_map_copy(map2);
  map1 = isl_map_normalize(map1);
  map2 = isl_map_normalize(map2);
  if (!map1 || !map2)
    goto error;
  equal = map1->n == map2->n;
  for (i = 0; equal && i < map1->n; ++i) {
    equal = isl_basic_map_plain_is_equal(map1->p[i], map2->p[i]);
    if (equal < 0)
      goto error;
  }
  isl_map_free(map1);
  isl_map_free(map2);
  return equal;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return isl_bool_error;
}
 
isl_bool isl_set_plain_is_equal(__isl_keep isl_set *set1,
  __isl_keep isl_set *set2)
{
  return isl_map_plain_is_equal(set_to_map(set1), set_to_map(set2));
}
 
/* Return the basic maps in "map" as a list.
 */
__isl_give isl_basic_map_list *isl_map_get_basic_map_list(
  __isl_keep isl_map *map)
{
  int i;
  isl_ctx *ctx;
  isl_basic_map_list *list;
 
  if (!map)
    return NULL;
  ctx = isl_map_get_ctx(map);
  list = isl_basic_map_list_alloc(ctx, map->n);
 
  for (i = 0; i < map->n; ++i) {
    isl_basic_map *bmap;
 
    bmap = isl_basic_map_copy(map->p[i]);
    list = isl_basic_map_list_add(list, bmap);
  }
 
  return list;
}
 
/* Return the intersection of the elements in the non-empty list "list".
 * All elements are assumed to live in the same space.
 */
__isl_give isl_basic_map *isl_basic_map_list_intersect(
  __isl_take isl_basic_map_list *list)
{
  int i;
  isl_size n;
  isl_basic_map *bmap;
 
  n = isl_basic_map_list_n_basic_map(list);
  if (n < 0)
    goto error;
  if (n < 1)
    isl_die(isl_basic_map_list_get_ctx(list), isl_error_invalid,
      "expecting non-empty list", goto error);
 
  bmap = isl_basic_map_list_get_basic_map(list, 0);
  for (i = 1; i < n; ++i) {
    isl_basic_map *bmap_i;
 
    bmap_i = isl_basic_map_list_get_basic_map(list, i);
    bmap = isl_basic_map_intersect(bmap, bmap_i);
  }
 
  isl_basic_map_list_free(list);
  return bmap;
error:
  isl_basic_map_list_free(list);
  return NULL;
}
 
/* Return the intersection of the elements in the non-empty list "list".
 * All elements are assumed to live in the same space.
 */
__isl_give isl_basic_set *isl_basic_set_list_intersect(
  __isl_take isl_basic_set_list *list)
{
  return isl_basic_map_list_intersect(list);
}
 
/* Return the union of the elements of "list".
 * The list is required to have at least one element.
 */
__isl_give isl_set *isl_basic_set_list_union(
  __isl_take isl_basic_set_list *list)
{
  int i;
  isl_size n;
  isl_space *space;
  isl_basic_set *bset;
  isl_set *set;
 
  n = isl_basic_set_list_n_basic_set(list);
  if (n < 0)
    goto error;
  if (n < 1)
    isl_die(isl_basic_set_list_get_ctx(list), isl_error_invalid,
      "expecting non-empty list", goto error);
 
  bset = isl_basic_set_list_get_basic_set(list, 0);
  space = isl_basic_set_get_space(bset);
  isl_basic_set_free(bset);
 
  set = isl_set_alloc_space(space, n, 0);
  for (i = 0; i < n; ++i) {
    bset = isl_basic_set_list_get_basic_set(list, i);
    set = isl_set_add_basic_set(set, bset);
  }
 
  isl_basic_set_list_free(list);
  return set;
error:
  isl_basic_set_list_free(list);
  return NULL;
}
 
/* Return the union of the elements in the non-empty list "list".
 * All elements are assumed to live in the same space.
 */
__isl_give isl_set *isl_set_list_union(__isl_take isl_set_list *list)
{
  int i;
  isl_size n;
  isl_set *set;
 
  n = isl_set_list_n_set(list);
  if (n < 0)
    goto error;
  if (n < 1)
    isl_die(isl_set_list_get_ctx(list), isl_error_invalid,
      "expecting non-empty list", goto error);
 
  set = isl_set_list_get_set(list, 0);
  for (i = 1; i < n; ++i) {
    isl_set *set_i;
 
    set_i = isl_set_list_get_set(list, i);
    set = isl_set_union(set, set_i);
  }
 
  isl_set_list_free(list);
  return set;
error:
  isl_set_list_free(list);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_product(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  isl_space *space_result = NULL;
  struct isl_basic_map *bmap;
  unsigned in1, in2, out1, out2, nparam, total, pos;
  struct isl_dim_map *dim_map1, *dim_map2;
 
  if (isl_basic_map_check_equal_params(bmap1, bmap2) < 0)
    goto error;
  space_result = isl_space_product(isl_space_copy(bmap1->dim),
               isl_space_copy(bmap2->dim));
 
  in1 = isl_basic_map_dim(bmap1, isl_dim_in);
  in2 = isl_basic_map_dim(bmap2, isl_dim_in);
  out1 = isl_basic_map_dim(bmap1, isl_dim_out);
  out2 = isl_basic_map_dim(bmap2, isl_dim_out);
  nparam = isl_basic_map_dim(bmap1, isl_dim_param);
 
  total = nparam + in1 + in2 + out1 + out2 + bmap1->n_div + bmap2->n_div;
  dim_map1 = isl_dim_map_alloc(bmap1->ctx, total);
  dim_map2 = isl_dim_map_alloc(bmap1->ctx, total);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_in, pos += nparam);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_in, pos += in1);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_out, pos += in2);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_out, pos += out1);
  isl_dim_map_div(dim_map1, bmap1, pos += out2);
  isl_dim_map_div(dim_map2, bmap2, pos += bmap1->n_div);
 
  bmap = isl_basic_map_alloc_space(space_result,
      bmap1->n_div + bmap2->n_div,
      bmap1->n_eq + bmap2->n_eq,
      bmap1->n_ineq + bmap2->n_ineq);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap1, dim_map1);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap2, dim_map2);
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_flat_product(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  isl_basic_map *prod;
 
  prod = isl_basic_map_product(bmap1, bmap2);
  prod = isl_basic_map_flatten(prod);
  return prod;
}
 
__isl_give isl_basic_set *isl_basic_set_flat_product(
  __isl_take isl_basic_set *bset1, __isl_take isl_basic_set *bset2)
{
  return isl_basic_map_flat_range_product(bset1, bset2);
}
 
__isl_give isl_basic_map *isl_basic_map_domain_product(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  isl_space *space1, *space2;
  isl_space *space_result = NULL;
  isl_basic_map *bmap;
  isl_size in1, in2, out, nparam;
  unsigned total, pos;
  struct isl_dim_map *dim_map1, *dim_map2;
 
  in1 = isl_basic_map_dim(bmap1, isl_dim_in);
  in2 = isl_basic_map_dim(bmap2, isl_dim_in);
  out = isl_basic_map_dim(bmap1, isl_dim_out);
  nparam = isl_basic_map_dim(bmap1, isl_dim_param);
  if (in1 < 0 || in2 < 0 || out < 0 || nparam < 0)
    goto error;
 
  space1 = isl_basic_map_get_space(bmap1);
  space2 = isl_basic_map_get_space(bmap2);
  space_result = isl_space_domain_product(space1, space2);
 
  total = nparam + in1 + in2 + out + bmap1->n_div + bmap2->n_div;
  dim_map1 = isl_dim_map_alloc(bmap1->ctx, total);
  dim_map2 = isl_dim_map_alloc(bmap1->ctx, total);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_in, pos += nparam);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_in, pos += in1);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_out, pos += in2);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_out, pos);
  isl_dim_map_div(dim_map1, bmap1, pos += out);
  isl_dim_map_div(dim_map2, bmap2, pos += bmap1->n_div);
 
  bmap = isl_basic_map_alloc_space(space_result,
      bmap1->n_div + bmap2->n_div,
      bmap1->n_eq + bmap2->n_eq,
      bmap1->n_ineq + bmap2->n_ineq);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap1, dim_map1);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap2, dim_map2);
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_range_product(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  isl_bool rational;
  isl_space *space_result = NULL;
  isl_basic_map *bmap;
  isl_size in, out1, out2, nparam;
  unsigned total, pos;
  struct isl_dim_map *dim_map1, *dim_map2;
 
  rational = isl_basic_map_is_rational(bmap1);
  if (rational >= 0 && rational)
    rational = isl_basic_map_is_rational(bmap2);
  in = isl_basic_map_dim(bmap1, isl_dim_in);
  out1 = isl_basic_map_dim(bmap1, isl_dim_out);
  out2 = isl_basic_map_dim(bmap2, isl_dim_out);
  nparam = isl_basic_map_dim(bmap1, isl_dim_param);
  if (in < 0 || out1 < 0 || out2 < 0 || nparam < 0 || rational < 0)
    goto error;
 
  if (isl_basic_map_check_equal_params(bmap1, bmap2) < 0)
    goto error;
 
  space_result = isl_space_range_product(isl_space_copy(bmap1->dim),
             isl_space_copy(bmap2->dim));
 
  total = nparam + in + out1 + out2 + bmap1->n_div + bmap2->n_div;
  dim_map1 = isl_dim_map_alloc(bmap1->ctx, total);
  dim_map2 = isl_dim_map_alloc(bmap1->ctx, total);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_param, pos = 0);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_in, pos += nparam);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_in, pos);
  isl_dim_map_dim(dim_map1, bmap1->dim, isl_dim_out, pos += in);
  isl_dim_map_dim(dim_map2, bmap2->dim, isl_dim_out, pos += out1);
  isl_dim_map_div(dim_map1, bmap1, pos += out2);
  isl_dim_map_div(dim_map2, bmap2, pos += bmap1->n_div);
 
  bmap = isl_basic_map_alloc_space(space_result,
      bmap1->n_div + bmap2->n_div,
      bmap1->n_eq + bmap2->n_eq,
      bmap1->n_ineq + bmap2->n_ineq);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap1, dim_map1);
  bmap = isl_basic_map_add_constraints_dim_map(bmap, bmap2, dim_map2);
  if (rational)
    bmap = isl_basic_map_set_rational(bmap);
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_basic_map_free(bmap1);
  isl_basic_map_free(bmap2);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_flat_range_product(
  __isl_take isl_basic_map *bmap1, __isl_take isl_basic_map *bmap2)
{
  isl_basic_map *prod;
 
  prod = isl_basic_map_range_product(bmap1, bmap2);
  prod = isl_basic_map_flatten_range(prod);
  return prod;
}
 
/* Apply "basic_map_product" to each pair of basic maps in "map1" and "map2"
 * and collect the results.
 * The result live in the space obtained by calling "space_product"
 * on the spaces of "map1" and "map2".
 * If "remove_duplicates" is set then the result may contain duplicates
 * (even if the inputs do not) and so we try and remove the obvious
 * duplicates.
 */
static __isl_give isl_map *map_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2,
  __isl_give isl_space *(*space_product)(__isl_take isl_space *left,
             __isl_take isl_space *right),
  __isl_give isl_basic_map *(*basic_map_product)(
    __isl_take isl_basic_map *left,
    __isl_take isl_basic_map *right),
  int remove_duplicates)
{
  unsigned flags = 0;
  struct isl_map *result;
  int i, j;
  isl_bool m;
 
  m = isl_map_has_equal_params(map1, map2);
  if (m < 0)
    goto error;
  if (!m)
    isl_die(isl_map_get_ctx(map1), isl_error_invalid,
      "parameters don't match", goto error);
 
  if (ISL_F_ISSET(map1, ISL_MAP_DISJOINT) &&
      ISL_F_ISSET(map2, ISL_MAP_DISJOINT))
    ISL_FL_SET(flags, ISL_MAP_DISJOINT);
 
  result = isl_map_alloc_space(space_product(isl_space_copy(map1->dim),
                 isl_space_copy(map2->dim)),
        map1->n * map2->n, flags);
  if (!result)
    goto error;
  for (i = 0; i < map1->n; ++i)
    for (j = 0; j < map2->n; ++j) {
      struct isl_basic_map *part;
      part = basic_map_product(isl_basic_map_copy(map1->p[i]),
             isl_basic_map_copy(map2->p[j]));
      if (isl_basic_map_is_empty(part))
        isl_basic_map_free(part);
      else
        result = isl_map_add_basic_map(result, part);
      if (!result)
        goto error;
    }
  if (remove_duplicates)
    result = isl_map_remove_obvious_duplicates(result);
  isl_map_free(map1);
  isl_map_free(map2);
  return result;
error:
  isl_map_free(map1);
  isl_map_free(map2);
  return NULL;
}
 
/* Given two maps A -> B and C -> D, construct a map [A -> C] -> [B -> D]
 */
__isl_give isl_map *isl_map_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map_align_params_bin(&map1, &map2);
  return map_product(map1, map2, &isl_space_product,
      &isl_basic_map_product, 0);
}
 
/* Given two maps A -> B and C -> D, construct a map (A, C) -> (B, D)
 */
__isl_give isl_map *isl_map_flat_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *prod;
 
  prod = isl_map_product(map1, map2);
  prod = isl_map_flatten(prod);
  return prod;
}
 
/* Given two set A and B, construct its Cartesian product A x B.
 */
__isl_give isl_set *isl_set_product(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  return isl_map_range_product(set1, set2);
}
 
__isl_give isl_set *isl_set_flat_product(__isl_take isl_set *set1,
  __isl_take isl_set *set2)
{
  return isl_map_flat_range_product(set1, set2);
}
 
/* Given two maps A -> B and C -> D, construct a map [A -> C] -> (B * D)
 */
__isl_give isl_map *isl_map_domain_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map_align_params_bin(&map1, &map2);
  return map_product(map1, map2, &isl_space_domain_product,
        &isl_basic_map_domain_product, 1);
}
 
/* Given two maps A -> B and C -> D, construct a map (A * C) -> [B -> D]
 */
__isl_give isl_map *isl_map_range_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map_align_params_bin(&map1, &map2);
  return map_product(map1, map2, &isl_space_range_product,
        &isl_basic_map_range_product, 1);
}
 
/* Given a map of the form [A -> B] -> [C -> D], return the map A -> C.
 */
__isl_give isl_map *isl_map_factor_domain(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size total1, keep1, total2, keep2;
 
  total1 = isl_map_dim(map, isl_dim_in);
  total2 = isl_map_dim(map, isl_dim_out);
  if (total1 < 0 || total2 < 0)
    return isl_map_free(map);
  if (!isl_space_domain_is_wrapping(map->dim) ||
      !isl_space_range_is_wrapping(map->dim))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "not a product", return isl_map_free(map));
 
  space = isl_map_get_space(map);
  space = isl_space_factor_domain(space);
  keep1 = isl_space_dim(space, isl_dim_in);
  keep2 = isl_space_dim(space, isl_dim_out);
  if (keep1 < 0 || keep2 < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_in, keep1, total1 - keep1);
  map = isl_map_project_out(map, isl_dim_out, keep2, total2 - keep2);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Given a map of the form [A -> B] -> [C -> D], return the map B -> D.
 */
__isl_give isl_map *isl_map_factor_range(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size total1, keep1, total2, keep2;
 
  total1 = isl_map_dim(map, isl_dim_in);
  total2 = isl_map_dim(map, isl_dim_out);
  if (total1 < 0 || total2 < 0)
    return isl_map_free(map);
  if (!isl_space_domain_is_wrapping(map->dim) ||
      !isl_space_range_is_wrapping(map->dim))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "not a product", return isl_map_free(map));
 
  space = isl_map_get_space(map);
  space = isl_space_factor_range(space);
  keep1 = isl_space_dim(space, isl_dim_in);
  keep2 = isl_space_dim(space, isl_dim_out);
  if (keep1 < 0 || keep2 < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_in, 0, total1 - keep1);
  map = isl_map_project_out(map, isl_dim_out, 0, total2 - keep2);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Given a map of the form [A -> B] -> C, return the map A -> C.
 */
__isl_give isl_map *isl_map_domain_factor_domain(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size total, keep;
 
  total = isl_map_dim(map, isl_dim_in);
  if (total < 0)
    return isl_map_free(map);
  if (!isl_space_domain_is_wrapping(map->dim))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "domain is not a product", return isl_map_free(map));
 
  space = isl_map_get_space(map);
  space = isl_space_domain_factor_domain(space);
  keep = isl_space_dim(space, isl_dim_in);
  if (keep < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_in, keep, total - keep);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Given a map of the form [A -> B] -> C, return the map B -> C.
 */
__isl_give isl_map *isl_map_domain_factor_range(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size total, keep;
 
  total = isl_map_dim(map, isl_dim_in);
  if (total < 0)
    return isl_map_free(map);
  if (!isl_space_domain_is_wrapping(map->dim))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "domain is not a product", return isl_map_free(map));
 
  space = isl_map_get_space(map);
  space = isl_space_domain_factor_range(space);
  keep = isl_space_dim(space, isl_dim_in);
  if (keep < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_in, 0, total - keep);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Given a map A -> [B -> C], extract the map A -> B.
 */
__isl_give isl_map *isl_map_range_factor_domain(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size total, keep;
 
  total = isl_map_dim(map, isl_dim_out);
  if (total < 0)
    return isl_map_free(map);
  if (!isl_space_range_is_wrapping(map->dim))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "range is not a product", return isl_map_free(map));
 
  space = isl_map_get_space(map);
  space = isl_space_range_factor_domain(space);
  keep = isl_space_dim(space, isl_dim_out);
  if (keep < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_out, keep, total - keep);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Given a map A -> [B -> C], extract the map A -> C.
 */
__isl_give isl_map *isl_map_range_factor_range(__isl_take isl_map *map)
{
  isl_space *space;
  isl_size total, keep;
 
  total = isl_map_dim(map, isl_dim_out);
  if (total < 0)
    return isl_map_free(map);
  if (!isl_space_range_is_wrapping(map->dim))
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "range is not a product", return isl_map_free(map));
 
  space = isl_map_get_space(map);
  space = isl_space_range_factor_range(space);
  keep = isl_space_dim(space, isl_dim_out);
  if (keep < 0)
    map = isl_map_free(map);
  map = isl_map_project_out(map, isl_dim_out, 0, total - keep);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Given two maps A -> B and C -> D, construct a map (A, C) -> (B * D)
 */
__isl_give isl_map *isl_map_flat_domain_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *prod;
 
  prod = isl_map_domain_product(map1, map2);
  prod = isl_map_flatten_domain(prod);
  return prod;
}
 
/* Given two maps A -> B and C -> D, construct a map (A * C) -> (B, D)
 */
__isl_give isl_map *isl_map_flat_range_product(__isl_take isl_map *map1,
  __isl_take isl_map *map2)
{
  isl_map *prod;
 
  prod = isl_map_range_product(map1, map2);
  prod = isl_map_flatten_range(prod);
  return prod;
}
 
uint32_t isl_basic_map_get_hash(__isl_keep isl_basic_map *bmap)
{
  int i;
  uint32_t hash = isl_hash_init();
  isl_size total;
 
  if (!bmap)
    return 0;
  bmap = isl_basic_map_copy(bmap);
  bmap = isl_basic_map_normalize(bmap);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return 0;
  isl_hash_byte(hash, bmap->n_eq & 0xFF);
  for (i = 0; i < bmap->n_eq; ++i) {
    uint32_t c_hash;
    c_hash = isl_seq_get_hash(bmap->eq[i], 1 + total);
    isl_hash_hash(hash, c_hash);
  }
  isl_hash_byte(hash, bmap->n_ineq & 0xFF);
  for (i = 0; i < bmap->n_ineq; ++i) {
    uint32_t c_hash;
    c_hash = isl_seq_get_hash(bmap->ineq[i], 1 + total);
    isl_hash_hash(hash, c_hash);
  }
  isl_hash_byte(hash, bmap->n_div & 0xFF);
  for (i = 0; i < bmap->n_div; ++i) {
    uint32_t c_hash;
    if (isl_int_is_zero(bmap->div[i][0]))
      continue;
    isl_hash_byte(hash, i & 0xFF);
    c_hash = isl_seq_get_hash(bmap->div[i], 1 + 1 + total);
    isl_hash_hash(hash, c_hash);
  }
  isl_basic_map_free(bmap);
  return hash;
}
 
uint32_t isl_basic_set_get_hash(__isl_keep isl_basic_set *bset)
{
  return isl_basic_map_get_hash(bset_to_bmap(bset));
}
 
uint32_t isl_map_get_hash(__isl_keep isl_map *map)
{
  int i;
  uint32_t hash;
 
  if (!map)
    return 0;
  map = isl_map_copy(map);
  map = isl_map_normalize(map);
  if (!map)
    return 0;
 
  hash = isl_hash_init();
  for (i = 0; i < map->n; ++i) {
    uint32_t bmap_hash;
    bmap_hash = isl_basic_map_get_hash(map->p[i]);
    isl_hash_hash(hash, bmap_hash);
  }
    
  isl_map_free(map);
 
  return hash;
}
 
uint32_t isl_set_get_hash(__isl_keep isl_set *set)
{
  return isl_map_get_hash(set_to_map(set));
}
 
/* Return the number of basic maps in the (current) representation of "map".
 */
isl_size isl_map_n_basic_map(__isl_keep isl_map *map)
{
  return map ? map->n : isl_size_error;
}
 
isl_size isl_set_n_basic_set(__isl_keep isl_set *set)
{
  return set ? set->n : isl_size_error;
}
 
isl_stat isl_map_foreach_basic_map(__isl_keep isl_map *map,
  isl_stat (*fn)(__isl_take isl_basic_map *bmap, void *user), void *user)
{
  int i;
 
  if (!map)
    return isl_stat_error;
 
  for (i = 0; i < map->n; ++i)
    if (fn(isl_basic_map_copy(map->p[i]), user) < 0)
      return isl_stat_error;
 
  return isl_stat_ok;
}
 
isl_stat isl_set_foreach_basic_set(__isl_keep isl_set *set,
  isl_stat (*fn)(__isl_take isl_basic_set *bset, void *user), void *user)
{
  int i;
 
  if (!set)
    return isl_stat_error;
 
  for (i = 0; i < set->n; ++i)
    if (fn(isl_basic_set_copy(set->p[i]), user) < 0)
      return isl_stat_error;
 
  return isl_stat_ok;
}
 
/* Does "test" succeed on every basic set in "set"?
 */
isl_bool isl_set_every_basic_set(__isl_keep isl_set *set,
  isl_bool (*test)(__isl_keep isl_basic_set *bset, void *user),
  void *user)
{
  int i;
 
  if (!set)
    return isl_bool_error;
 
  for (i = 0; i < set->n; ++i) {
    isl_bool r;
 
    r = test(set->p[i], user);
    if (r < 0 || !r)
      return r;
  }
 
  return isl_bool_true;
}
 
/* Return a list of basic sets, the union of which is equal to "set".
 */
__isl_give isl_basic_set_list *isl_set_get_basic_set_list(
  __isl_keep isl_set *set)
{
  int i;
  isl_basic_set_list *list;
 
  if (!set)
    return NULL;
 
  list = isl_basic_set_list_alloc(isl_set_get_ctx(set), set->n);
  for (i = 0; i < set->n; ++i) {
    isl_basic_set *bset;
 
    bset = isl_basic_set_copy(set->p[i]);
    list = isl_basic_set_list_add(list, bset);
  }
 
  return list;
}
 
__isl_give isl_basic_set *isl_basic_set_lift(__isl_take isl_basic_set *bset)
{
  isl_space *space;
 
  if (!bset)
    return NULL;
 
  bset = isl_basic_set_cow(bset);
  if (!bset)
    return NULL;
 
  space = isl_basic_set_get_space(bset);
  space = isl_space_lift(space, bset->n_div);
  if (!space)
    goto error;
  isl_space_free(bset->dim);
  bset->dim = space;
  bset->extra -= bset->n_div;
  bset->n_div = 0;
 
  bset = isl_basic_set_finalize(bset);
 
  return bset;
error:
  isl_basic_set_free(bset);
  return NULL;
}
 
__isl_give isl_set *isl_set_lift(__isl_take isl_set *set)
{
  int i;
  isl_space *space;
  unsigned n_div;
 
  set = set_from_map(isl_map_align_divs_internal(set_to_map(set)));
 
  if (!set)
    return NULL;
 
  set = isl_set_cow(set);
  if (!set)
    return NULL;
 
  n_div = set->p[0]->n_div;
  space = isl_set_get_space(set);
  space = isl_space_lift(space, n_div);
  if (!space)
    goto error;
  isl_space_free(set->dim);
  set->dim = space;
 
  for (i = 0; i < set->n; ++i) {
    set->p[i] = isl_basic_set_lift(set->p[i]);
    if (!set->p[i])
      goto error;
  }
 
  return set;
error:
  isl_set_free(set);
  return NULL;
}
 
int isl_basic_set_size(__isl_keep isl_basic_set *bset)
{
  isl_size dim;
  int size = 0;
 
  dim = isl_basic_set_dim(bset, isl_dim_all);
  if (dim < 0)
    return -1;
  size += bset->n_eq * (1 + dim);
  size += bset->n_ineq * (1 + dim);
  size += bset->n_div * (2 + dim);
 
  return size;
}
 
int isl_set_size(__isl_keep isl_set *set)
{
  int i;
  int size = 0;
 
  if (!set)
    return -1;
 
  for (i = 0; i < set->n; ++i)
    size += isl_basic_set_size(set->p[i]);
 
  return size;
}
 
/* Check if there is any lower bound (if lower == 0) and/or upper
 * bound (if upper == 0) on the specified dim.
 */
static isl_bool basic_map_dim_is_bounded(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos, int lower, int upper)
{
  int i;
  isl_bool involves;
  isl_size off;
 
  if (isl_basic_map_check_range(bmap, type, pos, 1) < 0)
    return isl_bool_error;
 
  off = isl_basic_map_var_offset(bmap, type);
  if (off < 0)
    return isl_bool_error;
  involves = isl_basic_map_any_div_involves_vars(bmap, off + pos, 1);
  if (involves < 0 || involves)
    return involves;
 
  for (i = 0; i < bmap->n_eq; ++i)
    if (!isl_int_is_zero(bmap->eq[i][1 + off + pos]))
      return isl_bool_true;
 
  for (i = 0; i < bmap->n_ineq; ++i) {
    int sgn = isl_int_sgn(bmap->ineq[i][1 + off + pos]);
    if (sgn > 0)
      lower = 1;
    if (sgn < 0)
      upper = 1;
  }
 
  return lower && upper;
}
 
isl_bool isl_basic_map_dim_is_bounded(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos)
{
  return basic_map_dim_is_bounded(bmap, type, pos, 0, 0);
}
 
isl_bool isl_basic_map_dim_has_lower_bound(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos)
{
  return basic_map_dim_is_bounded(bmap, type, pos, 0, 1);
}
 
isl_bool isl_basic_map_dim_has_upper_bound(__isl_keep isl_basic_map *bmap,
  enum isl_dim_type type, unsigned pos)
{
  return basic_map_dim_is_bounded(bmap, type, pos, 1, 0);
}
 
isl_bool isl_map_dim_is_bounded(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos)
{
  int i;
 
  if (!map)
    return isl_bool_error;
 
  for (i = 0; i < map->n; ++i) {
    isl_bool bounded;
    bounded = isl_basic_map_dim_is_bounded(map->p[i], type, pos);
    if (bounded < 0 || !bounded)
      return bounded;
  }
 
  return isl_bool_true;
}
 
/* Return true if the specified dim is involved in both an upper bound
 * and a lower bound.
 */
isl_bool isl_set_dim_is_bounded(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return isl_map_dim_is_bounded(set_to_map(set), type, pos);
}
 
/* Does "map" have a bound (according to "fn") for any of its basic maps?
 */
static isl_bool has_any_bound(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos,
  isl_bool (*fn)(__isl_keep isl_basic_map *bmap,
      enum isl_dim_type type, unsigned pos))
{
  int i;
 
  if (!map)
    return isl_bool_error;
 
  for (i = 0; i < map->n; ++i) {
    isl_bool bounded;
    bounded = fn(map->p[i], type, pos);
    if (bounded < 0 || bounded)
      return bounded;
  }
 
  return isl_bool_false;
}
 
/* Return 1 if the specified dim is involved in any lower bound.
 */
isl_bool isl_set_dim_has_any_lower_bound(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return has_any_bound(set, type, pos,
        &isl_basic_map_dim_has_lower_bound);
}
 
/* Return 1 if the specified dim is involved in any upper bound.
 */
isl_bool isl_set_dim_has_any_upper_bound(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return has_any_bound(set, type, pos,
        &isl_basic_map_dim_has_upper_bound);
}
 
/* Does "map" have a bound (according to "fn") for all of its basic maps?
 */
static isl_bool has_bound(__isl_keep isl_map *map,
  enum isl_dim_type type, unsigned pos,
  isl_bool (*fn)(__isl_keep isl_basic_map *bmap,
      enum isl_dim_type type, unsigned pos))
{
  int i;
 
  if (!map)
    return isl_bool_error;
 
  for (i = 0; i < map->n; ++i) {
    isl_bool bounded;
    bounded = fn(map->p[i], type, pos);
    if (bounded < 0 || !bounded)
      return bounded;
  }
 
  return isl_bool_true;
}
 
/* Return 1 if the specified dim has a lower bound (in each of its basic sets).
 */
isl_bool isl_set_dim_has_lower_bound(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return has_bound(set, type, pos, &isl_basic_map_dim_has_lower_bound);
}
 
/* Return 1 if the specified dim has an upper bound (in each of its basic sets).
 */
isl_bool isl_set_dim_has_upper_bound(__isl_keep isl_set *set,
  enum isl_dim_type type, unsigned pos)
{
  return has_bound(set, type, pos, &isl_basic_map_dim_has_upper_bound);
}
 
/* For each of the "n" variables starting at "first", determine
 * the sign of the variable and put the results in the first "n"
 * elements of the array "signs".
 * Sign
 *  1 means that the variable is non-negative
 *  -1 means that the variable is non-positive
 *  0 means the variable attains both positive and negative values.
 */
isl_stat isl_basic_set_vars_get_sign(__isl_keep isl_basic_set *bset,
  unsigned first, unsigned n, int *signs)
{
  isl_vec *bound = NULL;
  struct isl_tab *tab = NULL;
  struct isl_tab_undo *snap;
  int i;
  isl_size total;
 
  total = isl_basic_set_dim(bset, isl_dim_all);
  if (total < 0 || !signs)
    return isl_stat_error;
 
  bound = isl_vec_alloc(bset->ctx, 1 + total);
  tab = isl_tab_from_basic_set(bset, 0);
  if (!bound || !tab)
    goto error;
 
  isl_seq_clr(bound->el, bound->size);
  isl_int_set_si(bound->el[0], -1);
 
  snap = isl_tab_snap(tab);
  for (i = 0; i < n; ++i) {
    int empty;
 
    isl_int_set_si(bound->el[1 + first + i], -1);
    if (isl_tab_add_ineq(tab, bound->el) < 0)
      goto error;
    empty = tab->empty;
    isl_int_set_si(bound->el[1 + first + i], 0);
    if (isl_tab_rollback(tab, snap) < 0)
      goto error;
 
    if (empty) {
      signs[i] = 1;
      continue;
    }
 
    isl_int_set_si(bound->el[1 + first + i], 1);
    if (isl_tab_add_ineq(tab, bound->el) < 0)
      goto error;
    empty = tab->empty;
    isl_int_set_si(bound->el[1 + first + i], 0);
    if (isl_tab_rollback(tab, snap) < 0)
      goto error;
 
    signs[i] = empty ? -1 : 0;
  }
 
  isl_tab_free(tab);
  isl_vec_free(bound);
  return isl_stat_ok;
error:
  isl_tab_free(tab);
  isl_vec_free(bound);
  return isl_stat_error;
}
 
isl_stat isl_basic_set_dims_get_sign(__isl_keep isl_basic_set *bset,
  enum isl_dim_type type, unsigned first, unsigned n, int *signs)
{
  if (!bset || !signs)
    return isl_stat_error;
  if (isl_basic_set_check_range(bset, type, first, n) < 0)
    return isl_stat_error;
 
  first += pos(bset->dim, type) - 1;
  return isl_basic_set_vars_get_sign(bset, first, n, signs);
}
 
/* Is it possible for the integer division "div" to depend (possibly
 * indirectly) on any output dimensions?
 *
 * If the div is undefined, then we conservatively assume that it
 * may depend on them.
 * Otherwise, we check if it actually depends on them or on any integer
 * divisions that may depend on them.
 */
static isl_bool div_may_involve_output(__isl_keep isl_basic_map *bmap, int div)
{
  int i;
  isl_size n_out, n_div;
  unsigned o_out, o_div;
 
  if (isl_int_is_zero(bmap->div[div][0]))
    return isl_bool_true;
 
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (n_out < 0)
    return isl_bool_error;
  o_out = isl_basic_map_offset(bmap, isl_dim_out);
 
  if (isl_seq_any_non_zero(bmap->div[div] + 1 + o_out, n_out))
    return isl_bool_true;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_div < 0)
    return isl_bool_error;
  o_div = isl_basic_map_offset(bmap, isl_dim_div);
 
  for (i = 0; i < n_div; ++i) {
    isl_bool may_involve;
 
    if (isl_int_is_zero(bmap->div[div][1 + o_div + i]))
      continue;
    may_involve = div_may_involve_output(bmap, i);
    if (may_involve < 0 || may_involve)
      return may_involve;
  }
 
  return isl_bool_false;
}
 
/* Return the first integer division of "bmap" in the range
 * [first, first + n[ that may depend on any output dimensions and
 * that has a non-zero coefficient in "c" (where the first coefficient
 * in "c" corresponds to integer division "first").
 */
static int first_div_may_involve_output(__isl_keep isl_basic_map *bmap,
  isl_int *c, int first, int n)
{
  int k;
 
  if (!bmap)
    return -1;
 
  for (k = first; k < first + n; ++k) {
    isl_bool may_involve;
 
    if (isl_int_is_zero(c[k]))
      continue;
    may_involve = div_may_involve_output(bmap, k);
    if (may_involve < 0)
      return -1;
    if (may_involve)
      return k;
  }
 
  return first + n;
}
 
/* Look for a pair of inequality constraints in "bmap" of the form
 *
 *  -l + i >= 0   or    i >= l
 * and
 *  n + l - i >= 0    or    i <= l + n
 *
 * with n < "m" and i the output dimension at position "pos".
 * (Note that n >= 0 as otherwise the two constraints would conflict.)
 * Furthermore, "l" is only allowed to involve parameters, input dimensions
 * and earlier output dimensions, as well as integer divisions that do
 * not involve any of the output dimensions.
 *
 * Return the index of the first inequality constraint or bmap->n_ineq
 * if no such pair can be found.
 */
static int find_modulo_constraint_pair(__isl_keep isl_basic_map *bmap,
  int pos, isl_int m)
{
  int i, j;
  isl_ctx *ctx;
  isl_size total;
  isl_size n_div, n_out;
  unsigned o_div, o_out;
  int less;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (total < 0 || n_out < 0 || n_div < 0)
    return -1;
 
  ctx = isl_basic_map_get_ctx(bmap);
  o_out = isl_basic_map_offset(bmap, isl_dim_out);
  o_div = isl_basic_map_offset(bmap, isl_dim_div);
  for (i = 0; i < bmap->n_ineq; ++i) {
    if (!isl_int_abs_eq(bmap->ineq[i][o_out + pos], ctx->one))
      continue;
    if (isl_seq_any_non_zero(bmap->ineq[i] + o_out + pos + 1,
          n_out - (pos + 1)))
      continue;
    if (first_div_may_involve_output(bmap, bmap->ineq[i] + o_div,
            0, n_div) < n_div)
      continue;
    for (j = i + 1; j < bmap->n_ineq; ++j) {
      if (!isl_int_abs_eq(bmap->ineq[j][o_out + pos],
              ctx->one))
        continue;
      if (!isl_seq_is_neg(bmap->ineq[i] + 1,
              bmap->ineq[j] + 1, total))
        continue;
      break;
    }
    if (j >= bmap->n_ineq)
      continue;
    isl_int_add(bmap->ineq[i][0],
          bmap->ineq[i][0], bmap->ineq[j][0]);
    less = isl_int_abs_lt(bmap->ineq[i][0], m);
    isl_int_sub(bmap->ineq[i][0],
          bmap->ineq[i][0], bmap->ineq[j][0]);
    if (!less)
      continue;
    if (isl_int_is_one(bmap->ineq[i][o_out + pos]))
      return i;
    else
      return j;
  }
 
  return bmap->n_ineq;
}
 
/* Return the index of the equality of "bmap" that defines
 * the output dimension "pos" in terms of earlier dimensions.
 * The equality may also involve integer divisions, as long
 * as those integer divisions are defined in terms of
 * parameters or input dimensions.
 * In this case, *div is set to the number of integer divisions and
 * *ineq is set to the number of inequality constraints (provided
 * div and ineq are not NULL).
 *
 * The equality may also involve a single integer division involving
 * the output dimensions (typically only output dimension "pos") as
 * long as the coefficient of output dimension "pos" is 1 or -1 and
 * there is a pair of constraints i >= l and i <= l + n, with i referring
 * to output dimension "pos", l an expression involving only earlier
 * dimensions and n smaller than the coefficient of the integer division
 * in the equality.  In this case, the output dimension can be defined
 * in terms of a modulo expression that does not involve the integer division.
 * *div is then set to this single integer division and
 * *ineq is set to the index of constraint i >= l.
 *
 * Return bmap->n_eq if there is no such equality.
 * Return -1 on error.
 */
int isl_basic_map_output_defining_equality(__isl_keep isl_basic_map *bmap,
  int pos, int *div, int *ineq)
{
  int j, k, l;
  isl_size n_div, n_out;
  unsigned o_div, o_out;
 
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_out < 0 || n_div < 0)
    return -1;
 
  o_out = isl_basic_map_offset(bmap, isl_dim_out);
  o_div = isl_basic_map_offset(bmap, isl_dim_div);
 
  if (ineq)
    *ineq = bmap->n_ineq;
  if (div)
    *div = n_div;
  for (j = 0; j < bmap->n_eq; ++j) {
    if (isl_int_is_zero(bmap->eq[j][o_out + pos]))
      continue;
    if (isl_seq_any_non_zero(bmap->eq[j] + o_out + pos + 1,
          n_out - (pos + 1)))
      continue;
    k = first_div_may_involve_output(bmap, bmap->eq[j] + o_div,
            0, n_div);
    if (k >= n_div)
      return j;
    if (!isl_int_is_one(bmap->eq[j][o_out + pos]) &&
        !isl_int_is_negone(bmap->eq[j][o_out + pos]))
      continue;
    if (first_div_may_involve_output(bmap, bmap->eq[j] + o_div,
            k + 1, n_div - (k+1)) < n_div)
      continue;
    l = find_modulo_constraint_pair(bmap, pos,
            bmap->eq[j][o_div + k]);
    if (l < 0)
      return -1;
    if (l >= bmap->n_ineq)
      continue;
    if (div)
      *div = k;
    if (ineq)
      *ineq = l;
    return j;
  }
 
  return bmap->n_eq;
}
 
/* Check if the given basic map is obviously single-valued.
 * In particular, for each output dimension, check that there is
 * an equality that defines the output dimension in terms of
 * earlier dimensions.
 */
isl_bool isl_basic_map_plain_is_single_valued(__isl_keep isl_basic_map *bmap)
{
  int i;
  isl_size n_out;
 
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  if (n_out < 0)
    return isl_bool_error;
 
  for (i = 0; i < n_out; ++i) {
    int eq;
 
    eq = isl_basic_map_output_defining_equality(bmap, i,
                  NULL, NULL);
    if (eq < 0)
      return isl_bool_error;
    if (eq >= bmap->n_eq)
      return isl_bool_false;
  }
 
  return isl_bool_true;
}
 
/* Check if the given basic map is single-valued.
 * We simply compute
 *
 *  M \circ M^-1
 *
 * and check if the result is a subset of the identity mapping.
 */
isl_bool isl_basic_map_is_single_valued(__isl_keep isl_basic_map *bmap)
{
  isl_space *space;
  isl_basic_map *test;
  isl_basic_map *id;
  isl_bool sv;
 
  sv = isl_basic_map_plain_is_single_valued(bmap);
  if (sv < 0 || sv)
    return sv;
 
  test = isl_basic_map_reverse(isl_basic_map_copy(bmap));
  test = isl_basic_map_apply_range(test, isl_basic_map_copy(bmap));
 
  space = isl_basic_map_get_space(bmap);
  space = isl_space_map_from_set(isl_space_range(space));
  id = isl_basic_map_identity(space);
 
  sv = isl_basic_map_is_subset(test, id);
 
  isl_basic_map_free(test);
  isl_basic_map_free(id);
 
  return sv;
}
 
/* Check if the given map is obviously single-valued.
 */
isl_bool isl_map_plain_is_single_valued(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
  if (map->n == 0)
    return isl_bool_true;
  if (map->n >= 2)
    return isl_bool_false;
 
  return isl_basic_map_plain_is_single_valued(map->p[0]);
}
 
/* Check if the given map is single-valued.
 * We simply compute
 *
 *  M \circ M^-1
 *
 * and check if the result is a subset of the identity mapping.
 */
isl_bool isl_map_is_single_valued(__isl_keep isl_map *map)
{
  isl_space *space;
  isl_map *test;
  isl_map *id;
  isl_bool sv;
 
  sv = isl_map_plain_is_single_valued(map);
  if (sv < 0 || sv)
    return sv;
 
  test = isl_map_reverse(isl_map_copy(map));
  test = isl_map_apply_range(test, isl_map_copy(map));
 
  space = isl_space_map_from_set(isl_space_range(isl_map_get_space(map)));
  id = isl_map_identity(space);
 
  sv = isl_map_is_subset(test, id);
 
  isl_map_free(test);
  isl_map_free(id);
 
  return sv;
}
 
isl_bool isl_map_is_injective(__isl_keep isl_map *map)
{
  isl_bool in;
 
  map = isl_map_copy(map);
  map = isl_map_reverse(map);
  in = isl_map_is_single_valued(map);
  isl_map_free(map);
 
  return in;
}
 
/* Check if the given map is obviously injective.
 */
isl_bool isl_map_plain_is_injective(__isl_keep isl_map *map)
{
  isl_bool in;
 
  map = isl_map_copy(map);
  map = isl_map_reverse(map);
  in = isl_map_plain_is_single_valued(map);
  isl_map_free(map);
 
  return in;
}
 
isl_bool isl_map_is_bijective(__isl_keep isl_map *map)
{
  isl_bool sv;
 
  sv = isl_map_is_single_valued(map);
  if (sv < 0 || !sv)
    return sv;
 
  return isl_map_is_injective(map);
}
 
isl_bool isl_set_is_singleton(__isl_keep isl_set *set)
{
  return isl_map_is_single_valued(set_to_map(set));
}
 
/* Does "map" only map elements to themselves?
 *
 * If the domain and range spaces are different, then "map"
 * is considered not to be an identity relation, even if it is empty.
 * Otherwise, construct the maximal identity relation and
 * check whether "map" is a subset of this relation.
 */
isl_bool isl_map_is_identity(__isl_keep isl_map *map)
{
  isl_map *id;
  isl_bool equal, is_identity;
 
  equal = isl_map_tuple_is_equal(map, isl_dim_in, map, isl_dim_out);
  if (equal < 0 || !equal)
    return equal;
 
  id = isl_map_identity(isl_map_get_space(map));
  is_identity = isl_map_is_subset(map, id);
  isl_map_free(id);
 
  return is_identity;
}
 
int isl_map_is_translation(__isl_keep isl_map *map)
{
  int ok;
  isl_set *delta;
 
  delta = isl_map_deltas(isl_map_copy(map));
  ok = isl_set_is_singleton(delta);
  isl_set_free(delta);
 
  return ok;
}
 
static int unique(isl_int *p, unsigned pos, unsigned len)
{
  if (isl_seq_any_non_zero(p, pos))
    return 0;
  if (isl_seq_any_non_zero(p + pos + 1, len - pos - 1))
    return 0;
  return 1;
}
 
isl_bool isl_basic_set_is_box(__isl_keep isl_basic_set *bset)
{
  int i, j;
  isl_size nvar, ovar, n_div;
 
  n_div = isl_basic_set_dim(bset, isl_dim_div);
  if (n_div < 0)
    return isl_bool_error;
  if (n_div != 0)
    return isl_bool_false;
 
  nvar = isl_basic_set_dim(bset, isl_dim_set);
  ovar = isl_space_offset(bset->dim, isl_dim_set);
  if (nvar < 0 || ovar < 0)
    return isl_bool_error;
  for (j = 0; j < nvar; ++j) {
    int lower = 0, upper = 0;
    for (i = 0; i < bset->n_eq; ++i) {
      if (isl_int_is_zero(bset->eq[i][1 + ovar + j]))
        continue;
      if (!unique(bset->eq[i] + 1 + ovar, j, nvar))
        return isl_bool_false;
      break;
    }
    if (i < bset->n_eq)
      continue;
    for (i = 0; i < bset->n_ineq; ++i) {
      if (isl_int_is_zero(bset->ineq[i][1 + ovar + j]))
        continue;
      if (!unique(bset->ineq[i] + 1 + ovar, j, nvar))
        return isl_bool_false;
      if (isl_int_is_pos(bset->ineq[i][1 + ovar + j]))
        lower = 1;
      else
        upper = 1;
    }
    if (!lower || !upper)
      return isl_bool_false;
  }
 
  return isl_bool_true;
}
 
isl_bool isl_set_is_box(__isl_keep isl_set *set)
{
  if (!set)
    return isl_bool_error;
  if (set->n != 1)
    return isl_bool_false;
 
  return isl_basic_set_is_box(set->p[0]);
}
 
isl_bool isl_basic_set_is_wrapping(__isl_keep isl_basic_set *bset)
{
  if (!bset)
    return isl_bool_error;
  
  return isl_space_is_wrapping(bset->dim);
}
 
isl_bool isl_set_is_wrapping(__isl_keep isl_set *set)
{
  if (!set)
    return isl_bool_error;
  
  return isl_space_is_wrapping(set->dim);
}
 
/* Modify the space of "map" through a call to "change".
 * If "can_change" is set (not NULL), then first call it to check
 * if the modification is allowed, printing the error message "cannot_change"
 * if it is not.
 */
static __isl_give isl_map *isl_map_change_space(__isl_take isl_map *map,
  isl_bool (*can_change)(__isl_keep isl_map *map),
  const char *cannot_change,
  __isl_give isl_space *(*change)(__isl_take isl_space *space))
{
  isl_bool ok;
  isl_space *space;
 
  if (!map)
    return NULL;
 
  ok = can_change ? can_change(map) : isl_bool_true;
  if (ok < 0)
    return isl_map_free(map);
  if (!ok)
    isl_die(isl_map_get_ctx(map), isl_error_invalid, cannot_change,
      return isl_map_free(map));
 
  space = change(isl_map_get_space(map));
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
/* Is the domain of "map" a wrapped relation?
 */
isl_bool isl_map_domain_is_wrapping(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
 
  return isl_space_domain_is_wrapping(map->dim);
}
 
/* Does "map" have a wrapped relation in both domain and range?
 */
isl_bool isl_map_is_product(__isl_keep isl_map *map)
{
  return isl_space_is_product(isl_map_peek_space(map));
}
 
/* Is the range of "map" a wrapped relation?
 */
isl_bool isl_map_range_is_wrapping(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
 
  return isl_space_range_is_wrapping(map->dim);
}
 
__isl_give isl_basic_set *isl_basic_map_wrap(__isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_wrap(space);
  bmap = isl_basic_map_restore_space(bmap, space);
 
  bmap = isl_basic_map_finalize(bmap);
 
  return bset_from_bmap(bmap);
}
 
/* Given a map A -> B, return the set (A -> B).
 */
__isl_give isl_set *isl_map_wrap(__isl_take isl_map *map)
{
  return isl_map_change_space(map, NULL, NULL, &isl_space_wrap);
}
 
__isl_give isl_basic_map *isl_basic_set_unwrap(__isl_take isl_basic_set *bset)
{
  bset = isl_basic_set_cow(bset);
  if (!bset)
    return NULL;
 
  bset->dim = isl_space_unwrap(bset->dim);
  if (!bset->dim)
    goto error;
 
  bset = isl_basic_set_finalize(bset);
 
  return bset_to_bmap(bset);
error:
  isl_basic_set_free(bset);
  return NULL;
}
 
/* Given a set (A -> B), return the map A -> B.
 * Error out if "set" is not of the form (A -> B).
 */
__isl_give isl_map *isl_set_unwrap(__isl_take isl_set *set)
{
  return isl_map_change_space(set, &isl_set_is_wrapping,
            "not a wrapping set", &isl_space_unwrap);
}
 
__isl_give isl_basic_map *isl_basic_map_reset(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_reset(space, type);
  bmap = isl_basic_map_restore_space(bmap, space);
 
  bmap = isl_basic_map_mark_final(bmap);
 
  return bmap;
}
 
__isl_give isl_map *isl_map_reset(__isl_take isl_map *map,
  enum isl_dim_type type)
{
  int i;
  isl_space *space;
 
  if (!map)
    return NULL;
 
  if (!isl_space_is_named_or_nested(map->dim, type))
    return map;
 
  map = isl_map_cow(map);
  if (!map)
    return NULL;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_reset(map->p[i], type);
    if (!map->p[i])
      goto error;
  }
 
  space = isl_map_take_space(map);
  space = isl_space_reset(space, type);
  map = isl_map_restore_space(map, space);
 
  return map;
error:
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_basic_map *isl_basic_map_flatten(__isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_flatten(space);
  bmap = isl_basic_map_restore_space(bmap, space);
 
  bmap = isl_basic_map_mark_final(bmap);
 
  return bmap;
}
 
__isl_give isl_basic_set *isl_basic_set_flatten(__isl_take isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_flatten(bset_to_bmap(bset)));
}
 
__isl_give isl_basic_map *isl_basic_map_flatten_domain(
  __isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_flatten_domain(space);
  bmap = isl_basic_map_restore_space(bmap, space);
 
  bmap = isl_basic_map_mark_final(bmap);
 
  return bmap;
}
 
__isl_give isl_basic_map *isl_basic_map_flatten_range(
  __isl_take isl_basic_map *bmap)
{
  isl_space *space;
 
  space = isl_basic_map_take_space(bmap);
  space = isl_space_flatten_range(space);
  bmap = isl_basic_map_restore_space(bmap, space);
 
  bmap = isl_basic_map_mark_final(bmap);
 
  return bmap;
}
 
/* Remove any internal structure from the spaces of domain and range of "map".
 */
__isl_give isl_map *isl_map_flatten(__isl_take isl_map *map)
{
  if (!map)
    return NULL;
 
  if (!map->dim->nested[0] && !map->dim->nested[1])
    return map;
 
  return isl_map_change_space(map, NULL, NULL, &isl_space_flatten);
}
 
__isl_give isl_set *isl_set_flatten(__isl_take isl_set *set)
{
  return set_from_map(isl_map_flatten(set_to_map(set)));
}
 
__isl_give isl_map *isl_set_flatten_map(__isl_take isl_set *set)
{
  isl_space *space, *flat_space;
  isl_map *map;
 
  space = isl_set_get_space(set);
  flat_space = isl_space_flatten(isl_space_copy(space));
  map = isl_map_identity(isl_space_join(isl_space_reverse(space),
            flat_space));
  map = isl_map_intersect_domain(map, set);
 
  return map;
}
 
/* Remove any internal structure from the space of the domain of "map".
 */
__isl_give isl_map *isl_map_flatten_domain(__isl_take isl_map *map)
{
  if (!map)
    return NULL;
 
  if (!map->dim->nested[0])
    return map;
 
  return isl_map_change_space(map, NULL, NULL, &isl_space_flatten_domain);
}
 
/* Remove any internal structure from the space of the range of "map".
 */
__isl_give isl_map *isl_map_flatten_range(__isl_take isl_map *map)
{
  if (!map)
    return NULL;
 
  if (!map->dim->nested[1])
    return map;
 
  return isl_map_change_space(map, NULL, NULL, &isl_space_flatten_range);
}
 
/* Reorder the dimensions of "bmap" according to the given dim_map
 * and set the dimension specification to "space" and
 * perform Gaussian elimination on the result.
 */
__isl_give isl_basic_map *isl_basic_map_realign(__isl_take isl_basic_map *bmap,
  __isl_take isl_space *space, __isl_take struct isl_dim_map *dim_map)
{
  isl_basic_map *res;
  unsigned flags;
  isl_size n_div;
 
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_div < 0 || !space || !dim_map)
    goto error;
 
  flags = bmap->flags;
  ISL_FL_CLR(flags, ISL_BASIC_MAP_FINAL);
  ISL_FL_CLR(flags, ISL_BASIC_MAP_SORTED);
  ISL_FL_CLR(flags, ISL_BASIC_MAP_NORMALIZED_DIVS);
  res = isl_basic_map_alloc_space(space, n_div, bmap->n_eq, bmap->n_ineq);
  res = isl_basic_map_add_constraints_dim_map(res, bmap, dim_map);
  if (res)
    res->flags = flags;
  res = isl_basic_map_gauss(res, NULL);
  res = isl_basic_map_finalize(res);
  return res;
error:
  isl_dim_map_free(dim_map);
  isl_basic_map_free(bmap);
  isl_space_free(space);
  return NULL;
}
 
/* Reorder the dimensions of "map" according to given reordering.
 */
__isl_give isl_map *isl_map_realign(__isl_take isl_map *map,
  __isl_take isl_reordering *r)
{
  int i;
  struct isl_dim_map *dim_map;
 
  map = isl_map_cow(map);
  dim_map = isl_dim_map_from_reordering(r);
  if (!map || !r || !dim_map)
    goto error;
 
  for (i = 0; i < map->n; ++i) {
    struct isl_dim_map *dim_map_i;
    isl_space *space;
 
    dim_map_i = isl_dim_map_extend(dim_map, map->p[i]);
 
    space = isl_reordering_get_space(r);
    map->p[i] = isl_basic_map_realign(map->p[i], space, dim_map_i);
 
    if (!map->p[i])
      goto error;
  }
 
  map = isl_map_reset_space(map, isl_reordering_get_space(r));
  map = isl_map_unmark_normalized(map);
 
  isl_reordering_free(r);
  isl_dim_map_free(dim_map);
  return map;
error:
  isl_dim_map_free(dim_map);
  isl_map_free(map);
  isl_reordering_free(r);
  return NULL;
}
 
__isl_give isl_set *isl_set_realign(__isl_take isl_set *set,
  __isl_take isl_reordering *r)
{
  return set_from_map(isl_map_realign(set_to_map(set), r));
}
 
__isl_give isl_map *isl_map_align_params(__isl_take isl_map *map,
  __isl_take isl_space *model)
{
  isl_ctx *ctx;
  isl_bool aligned;
 
  if (!map || !model)
    goto error;
 
  ctx = isl_space_get_ctx(model);
  if (!isl_space_has_named_params(model))
    isl_die(ctx, isl_error_invalid,
      "model has unnamed parameters", goto error);
  if (isl_map_check_named_params(map) < 0)
    goto error;
  aligned = isl_map_space_has_equal_params(map, model);
  if (aligned < 0)
    goto error;
  if (!aligned) {
    isl_space *space;
    isl_reordering *exp;
 
    space = isl_map_peek_space(map);
    exp = isl_parameter_alignment_reordering(space, model);
    map = isl_map_realign(map, exp);
  }
 
  isl_space_free(model);
  return map;
error:
  isl_space_free(model);
  isl_map_free(map);
  return NULL;
}
 
__isl_give isl_set *isl_set_align_params(__isl_take isl_set *set,
  __isl_take isl_space *model)
{
  return isl_map_align_params(set, model);
}
 
/* Align the parameters of "bmap" to those of "model", introducing
 * additional parameters if needed.
 */
__isl_give isl_basic_map *isl_basic_map_align_params(
  __isl_take isl_basic_map *bmap, __isl_take isl_space *model)
{
  isl_ctx *ctx;
  isl_bool equal_params;
  isl_space *bmap_space;
 
  if (!bmap || !model)
    goto error;
 
  ctx = isl_space_get_ctx(model);
  if (!isl_space_has_named_params(model))
    isl_die(ctx, isl_error_invalid,
      "model has unnamed parameters", goto error);
  if (isl_basic_map_check_named_params(bmap) < 0)
    goto error;
  bmap_space = isl_basic_map_peek_space(bmap);
  equal_params = isl_space_has_equal_params(bmap_space, model);
  if (equal_params < 0)
    goto error;
  if (!equal_params) {
    isl_reordering *exp;
    struct isl_dim_map *dim_map;
 
    exp = isl_parameter_alignment_reordering(bmap_space, model);
    dim_map = isl_dim_map_from_reordering(exp);
    bmap = isl_basic_map_realign(bmap,
            isl_reordering_get_space(exp),
            isl_dim_map_extend(dim_map, bmap));
    isl_reordering_free(exp);
    isl_dim_map_free(dim_map);
  }
 
  isl_space_free(model);
  return bmap;
error:
  isl_space_free(model);
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Do "bset" and "space" have the same parameters?
 */
isl_bool isl_basic_set_space_has_equal_params(__isl_keep isl_basic_set *bset,
  __isl_keep isl_space *space)
{
  isl_space *bset_space;
 
  bset_space = isl_basic_set_peek_space(bset);
  return isl_space_has_equal_params(bset_space, space);
}
 
/* Do "map" and "space" have the same parameters?
 */
isl_bool isl_map_space_has_equal_params(__isl_keep isl_map *map,
  __isl_keep isl_space *space)
{
  isl_space *map_space;
 
  map_space = isl_map_peek_space(map);
  return isl_space_has_equal_params(map_space, space);
}
 
/* Do "set" and "space" have the same parameters?
 */
isl_bool isl_set_space_has_equal_params(__isl_keep isl_set *set,
  __isl_keep isl_space *space)
{
  return isl_map_space_has_equal_params(set_to_map(set), space);
}
 
/* Align the parameters of "bset" to those of "model", introducing
 * additional parameters if needed.
 */
__isl_give isl_basic_set *isl_basic_set_align_params(
  __isl_take isl_basic_set *bset, __isl_take isl_space *model)
{
  return isl_basic_map_align_params(bset, model);
}
 
#undef TYPE
#define TYPE  isl_map
#define isl_map_drop_dims isl_map_drop
#include "isl_drop_unused_params_templ.c"
 
/* Drop all parameters not referenced by "set".
 */
__isl_give isl_set *isl_set_drop_unused_params(
  __isl_take isl_set *set)
{
  return set_from_map(isl_map_drop_unused_params(set_to_map(set)));
}
 
#undef TYPE
#define TYPE  isl_basic_map
#define isl_basic_map_drop_dims isl_basic_map_drop
#include "isl_drop_unused_params_templ.c"
 
/* Drop all parameters not referenced by "bset".
 */
__isl_give isl_basic_set *isl_basic_set_drop_unused_params(
  __isl_take isl_basic_set *bset)
{
  return bset_from_bmap(isl_basic_map_drop_unused_params(
              bset_to_bmap(bset)));
}
 
/* Given a tuple of identifiers "tuple" in a space that corresponds
 * to that of "set", if any of those identifiers appear as parameters
 * in "set", then equate those parameters with the corresponding
 * set dimensions and project out the parameters.
 * The result therefore has no such parameters.
 */
static __isl_give isl_set *equate_params(__isl_take isl_set *set,
  __isl_keep isl_multi_id *tuple)
{
  int i;
  isl_size n;
  isl_space *set_space, *tuple_space;
 
  set_space = isl_set_peek_space(set);
  tuple_space = isl_multi_id_peek_space(tuple);
  if (isl_space_check_equal_tuples(tuple_space, set_space) < 0)
    return isl_set_free(set);
  n = isl_multi_id_size(tuple);
  if (n < 0)
    return isl_set_free(set);
  for (i = 0; i < n; ++i) {
    isl_id *id;
    int pos;
 
    id = isl_multi_id_get_at(tuple, i);
    if (!id)
      return isl_set_free(set);
    pos = isl_set_find_dim_by_id(set, isl_dim_param, id);
    isl_id_free(id);
    if (pos < 0)
      continue;
    set = isl_set_equate(set, isl_dim_param, pos, isl_dim_set, i);
    set = isl_set_project_out(set, isl_dim_param, pos, 1);
  }
  return set;
}
 
/* Bind the set dimensions of "set" to parameters with identifiers
 * specified by "tuple", living in the same space as "set".
 *
 * If no parameters with these identifiers appear in "set" already,
 * then the set dimensions are simply reinterpreted as parameters.
 * Otherwise, the parameters are first equated to the corresponding
 * set dimensions.
 */
__isl_give isl_set *isl_set_bind(__isl_take isl_set *set,
  __isl_take isl_multi_id *tuple)
{
  isl_space *space;
 
  set = equate_params(set, tuple);
  space = isl_set_get_space(set);
  space = isl_space_bind_set(space, tuple);
  isl_multi_id_free(tuple);
  set = isl_set_reset_space(set, space);
 
  return set;
}
 
/* Given a tuple of identifiers "tuple" in a space that corresponds
 * to the domain of "map", if any of those identifiers appear as parameters
 * in "map", then equate those parameters with the corresponding
 * input dimensions and project out the parameters.
 * The result therefore has no such parameters.
 */
static __isl_give isl_map *map_equate_params(__isl_take isl_map *map,
  __isl_keep isl_multi_id *tuple)
{
  int i;
  isl_size n;
  isl_space *map_space, *tuple_space;
 
  map_space = isl_map_peek_space(map);
  tuple_space = isl_multi_id_peek_space(tuple);
  if (isl_space_check_domain_tuples(tuple_space, map_space) < 0)
    return isl_map_free(map);
  n = isl_multi_id_size(tuple);
  if (n < 0)
    return isl_map_free(map);
  for (i = 0; i < n; ++i) {
    isl_id *id;
    int pos;
 
    id = isl_multi_id_get_at(tuple, i);
    if (!id)
      return isl_map_free(map);
    pos = isl_map_find_dim_by_id(map, isl_dim_param, id);
    isl_id_free(id);
    if (pos < 0)
      continue;
    map = isl_map_equate(map, isl_dim_param, pos, isl_dim_in, i);
    map = isl_map_project_out(map, isl_dim_param, pos, 1);
  }
  return map;
}
 
/* Bind the input dimensions of "map" to parameters with identifiers
 * specified by "tuple", living in the domain space of "map".
 *
 * If no parameters with these identifiers appear in "map" already,
 * then the input dimensions are simply reinterpreted as parameters.
 * Otherwise, the parameters are first equated to the corresponding
 * input dimensions.
 */
__isl_give isl_set *isl_map_bind_domain(__isl_take isl_map *map,
  __isl_take isl_multi_id *tuple)
{
  isl_space *space;
  isl_set *set;
 
  map = map_equate_params(map, tuple);
  space = isl_map_get_space(map);
  space = isl_space_bind_map_domain(space, tuple);
  isl_multi_id_free(tuple);
  set = set_from_map(isl_map_reset_space(map, space));
 
  return set;
}
 
/* Bind the output dimensions of "map" to parameters with identifiers
 * specified by "tuple", living in the range space of "map".
 *
 * Since binding is more easily implemented on the domain,
 * bind the input dimensions of the inverse of "map".
 */
__isl_give isl_set *isl_map_bind_range(__isl_take isl_map *map,
  __isl_take isl_multi_id *tuple)
{
  return isl_map_bind_domain(isl_map_reverse(map), tuple);
}
 
/* Insert a domain corresponding to "tuple"
 * into the nullary or unary relation "set".
 * The result has an extra initial tuple and is therefore
 * either a unary or binary relation.
 * Any parameters with identifiers in "tuple" are reinterpreted
 * as the corresponding domain dimensions.
 */
static __isl_give isl_map *unbind_params_insert_domain(
  __isl_take isl_set *set, __isl_take isl_multi_id *tuple)
{
  isl_space *space;
  isl_reordering *r;
 
  space = isl_set_peek_space(set);
  r = isl_reordering_unbind_params_insert_domain(space, tuple);
  isl_multi_id_free(tuple);
 
  return isl_map_realign(set_to_map(set), r);
}
 
/* Construct a set with "tuple" as domain from the parameter domain "set".
 * Any parameters with identifiers in "tuple" are reinterpreted
 * as the corresponding set dimensions.
 */
__isl_give isl_set *isl_set_unbind_params(__isl_take isl_set *set,
  __isl_take isl_multi_id *tuple)
{
  isl_bool is_params;
 
  is_params = isl_set_is_params(set);
  if (is_params < 0)
    set = isl_set_free(set);
  else if (!is_params)
    isl_die(isl_set_get_ctx(set), isl_error_invalid,
      "expecting parameter domain", set = isl_set_free(set));
  return set_from_map(unbind_params_insert_domain(set, tuple));
}
 
/* Check that "set" is a proper set, i.e., that it is not a parameter domain.
 */
static isl_stat isl_set_check_is_set(__isl_keep isl_set *set)
{
  isl_bool is_params;
 
  is_params = isl_set_is_params(set);
  if (is_params < 0)
    return isl_stat_error;
  else if (is_params)
    isl_die(isl_set_get_ctx(set), isl_error_invalid,
      "expecting proper set", return isl_stat_error);
 
  return isl_stat_ok;
}
 
/* Construct a map with "domain" as domain and "set" as range.
 * Any parameters with identifiers in "domain" are reinterpreted
 * as the corresponding domain dimensions.
 */
__isl_give isl_map *isl_set_unbind_params_insert_domain(
  __isl_take isl_set *set, __isl_take isl_multi_id *domain)
{
  if (isl_set_check_is_set(set) < 0)
    set = isl_set_free(set);
  return unbind_params_insert_domain(set, domain);
}
 
/* Construct a map with "domain" as domain and "set" as range.
 */
__isl_give isl_map *isl_set_insert_domain(__isl_take isl_set *set,
  __isl_take isl_space *domain)
{
  isl_size dim;
  isl_space *space;
  isl_map *map;
 
  if (isl_set_check_is_set(set) < 0 || isl_space_check_is_set(domain) < 0)
    domain = isl_space_free(domain);
  dim = isl_space_dim(domain, isl_dim_set);
  if (dim < 0)
    domain = isl_space_free(domain);
  space = isl_set_get_space(set);
  domain = isl_space_replace_params(domain, space);
  space = isl_space_map_from_domain_and_range(domain, space);
 
  map = isl_map_from_range(set);
  map = isl_map_add_dims(map, isl_dim_in, dim);
  map = isl_map_reset_space(map, space);
 
  return map;
}
 
__isl_give isl_mat *isl_basic_map_equalities_matrix(
    __isl_keep isl_basic_map *bmap, enum isl_dim_type c1,
    enum isl_dim_type c2, enum isl_dim_type c3,
    enum isl_dim_type c4, enum isl_dim_type c5)
{
  enum isl_dim_type c[5] = { c1, c2, c3, c4, c5 };
  struct isl_mat *mat;
  int i, j, k;
  int pos;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return NULL;
  mat = isl_mat_alloc(bmap->ctx, bmap->n_eq, total + 1);
  if (!mat)
    return NULL;
  for (i = 0; i < bmap->n_eq; ++i)
    for (j = 0, pos = 0; j < 5; ++j) {
      int off = isl_basic_map_offset(bmap, c[j]);
      isl_size dim = isl_basic_map_dim(bmap, c[j]);
      if (dim < 0)
        return isl_mat_free(mat);
      for (k = 0; k < dim; ++k) {
        isl_int_set(mat->row[i][pos],
              bmap->eq[i][off + k]);
        ++pos;
      }
    }
 
  return mat;
}
 
__isl_give isl_mat *isl_basic_map_inequalities_matrix(
    __isl_keep isl_basic_map *bmap, enum isl_dim_type c1,
    enum isl_dim_type c2, enum isl_dim_type c3,
    enum isl_dim_type c4, enum isl_dim_type c5)
{
  enum isl_dim_type c[5] = { c1, c2, c3, c4, c5 };
  struct isl_mat *mat;
  int i, j, k;
  int pos;
  isl_size total;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (total < 0)
    return NULL;
  mat = isl_mat_alloc(bmap->ctx, bmap->n_ineq, total + 1);
  if (!mat)
    return NULL;
  for (i = 0; i < bmap->n_ineq; ++i)
    for (j = 0, pos = 0; j < 5; ++j) {
      int off = isl_basic_map_offset(bmap, c[j]);
      isl_size dim = isl_basic_map_dim(bmap, c[j]);
      if (dim < 0)
        return isl_mat_free(mat);
      for (k = 0; k < dim; ++k) {
        isl_int_set(mat->row[i][pos],
              bmap->ineq[i][off + k]);
        ++pos;
      }
    }
 
  return mat;
}
 
__isl_give isl_basic_map *isl_basic_map_from_constraint_matrices(
  __isl_take isl_space *space,
  __isl_take isl_mat *eq, __isl_take isl_mat *ineq, enum isl_dim_type c1,
  enum isl_dim_type c2, enum isl_dim_type c3,
  enum isl_dim_type c4, enum isl_dim_type c5)
{
  enum isl_dim_type c[5] = { c1, c2, c3, c4, c5 };
  isl_basic_map *bmap = NULL;
  isl_size dim;
  unsigned total;
  unsigned extra;
  int i, j, k, l;
  int pos;
 
  dim = isl_space_dim(space, isl_dim_all);
  if (dim < 0 || !eq || !ineq)
    goto error;
 
  if (eq->n_col != ineq->n_col)
    isl_die(space->ctx, isl_error_invalid,
      "equalities and inequalities matrices should have "
      "same number of columns", goto error);
 
  total = 1 + dim;
 
  if (eq->n_col < total)
    isl_die(space->ctx, isl_error_invalid,
      "number of columns too small", goto error);
 
  extra = eq->n_col - total;
 
  bmap = isl_basic_map_alloc_space(isl_space_copy(space), extra,
               eq->n_row, ineq->n_row);
  if (!bmap)
    goto error;
  for (i = 0; i < extra; ++i) {
    k = isl_basic_map_alloc_div(bmap);
    if (k < 0)
      goto error;
    isl_int_set_si(bmap->div[k][0], 0);
  }
  for (i = 0; i < eq->n_row; ++i) {
    l = isl_basic_map_alloc_equality(bmap);
    if (l < 0)
      goto error;
    for (j = 0, pos = 0; j < 5; ++j) {
      int off = isl_basic_map_offset(bmap, c[j]);
      isl_size dim = isl_basic_map_dim(bmap, c[j]);
      if (dim < 0)
        goto error;
      for (k = 0; k < dim; ++k) {
        isl_int_set(bmap->eq[l][off + k], 
              eq->row[i][pos]);
        ++pos;
      }
    }
  }
  for (i = 0; i < ineq->n_row; ++i) {
    l = isl_basic_map_alloc_inequality(bmap);
    if (l < 0)
      goto error;
    for (j = 0, pos = 0; j < 5; ++j) {
      int off = isl_basic_map_offset(bmap, c[j]);
      isl_size dim = isl_basic_map_dim(bmap, c[j]);
      if (dim < 0)
        goto error;
      for (k = 0; k < dim; ++k) {
        isl_int_set(bmap->ineq[l][off + k], 
              ineq->row[i][pos]);
        ++pos;
      }
    }
  }
 
  isl_space_free(space);
  isl_mat_free(eq);
  isl_mat_free(ineq);
 
  bmap = isl_basic_map_simplify(bmap);
  return isl_basic_map_finalize(bmap);
error:
  isl_space_free(space);
  isl_mat_free(eq);
  isl_mat_free(ineq);
  isl_basic_map_free(bmap);
  return NULL;
}
 
__isl_give isl_mat *isl_basic_set_equalities_matrix(
  __isl_keep isl_basic_set *bset, enum isl_dim_type c1,
  enum isl_dim_type c2, enum isl_dim_type c3, enum isl_dim_type c4)
{
  return isl_basic_map_equalities_matrix(bset_to_bmap(bset),
            c1, c2, c3, c4, isl_dim_in);
}
 
__isl_give isl_mat *isl_basic_set_inequalities_matrix(
  __isl_keep isl_basic_set *bset, enum isl_dim_type c1,
  enum isl_dim_type c2, enum isl_dim_type c3, enum isl_dim_type c4)
{
  return isl_basic_map_inequalities_matrix(bset_to_bmap(bset),
             c1, c2, c3, c4, isl_dim_in);
}
 
__isl_give isl_basic_set *isl_basic_set_from_constraint_matrices(
  __isl_take isl_space *space,
  __isl_take isl_mat *eq, __isl_take isl_mat *ineq, enum isl_dim_type c1,
  enum isl_dim_type c2, enum isl_dim_type c3, enum isl_dim_type c4)
{
  isl_basic_map *bmap;
  bmap = isl_basic_map_from_constraint_matrices(space, eq, ineq,
               c1, c2, c3, c4, isl_dim_in);
  return bset_from_bmap(bmap);
}
 
isl_bool isl_basic_map_can_zip(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
  
  return isl_space_can_zip(bmap->dim);
}
 
isl_bool isl_map_can_zip(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
  
  return isl_space_can_zip(map->dim);
}
 
/* Given a basic map (A -> B) -> (C -> D), return the corresponding basic map
 * (A -> C) -> (B -> D).
 */
__isl_give isl_basic_map *isl_basic_map_zip(__isl_take isl_basic_map *bmap)
{
  unsigned pos;
  isl_size n_in;
  isl_size n1;
  isl_size n2;
 
  if (!bmap)
    return NULL;
 
  if (!isl_basic_map_can_zip(bmap))
    isl_die(bmap->ctx, isl_error_invalid,
      "basic map cannot be zipped", goto error);
  n_in = isl_space_dim(bmap->dim->nested[0], isl_dim_in);
  n1 = isl_space_dim(bmap->dim->nested[0], isl_dim_out);
  n2 = isl_space_dim(bmap->dim->nested[1], isl_dim_in);
  if (n_in < 0 || n1 < 0 || n2 < 0)
    return isl_basic_map_free(bmap);
  pos = isl_basic_map_offset(bmap, isl_dim_in) + n_in;
  bmap = isl_basic_map_cow(bmap);
  bmap = isl_basic_map_swap_vars(bmap, pos, n1, n2);
  if (!bmap)
    return NULL;
  bmap->dim = isl_space_zip(bmap->dim);
  if (!bmap->dim)
    goto error;
  bmap = isl_basic_map_mark_final(bmap);
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Given a map (A -> B) -> (C -> D), return the corresponding map
 * (A -> C) -> (B -> D).
 */
__isl_give isl_map *isl_map_zip(__isl_take isl_map *map)
{
  if (!map)
    return NULL;
 
  if (!isl_map_can_zip(map))
    isl_die(map->ctx, isl_error_invalid, "map cannot be zipped",
      goto error);
 
  return isl_map_transform(map, &isl_space_zip, &isl_basic_map_zip);
error:
  isl_map_free(map);
  return NULL;
}
 
/* Can we apply isl_basic_map_curry to "bmap"?
 * That is, does it have a nested relation in its domain?
 */
isl_bool isl_basic_map_can_curry(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
 
  return isl_space_can_curry(bmap->dim);
}
 
/* Can we apply isl_map_curry to "map"?
 * That is, does it have a nested relation in its domain?
 */
isl_bool isl_map_can_curry(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
 
  return isl_space_can_curry(map->dim);
}
 
/* Given a basic map (A -> B) -> C, return the corresponding basic map
 * A -> (B -> C).
 */
__isl_give isl_basic_map *isl_basic_map_curry(__isl_take isl_basic_map *bmap)
{
 
  if (!bmap)
    return NULL;
 
  if (!isl_basic_map_can_curry(bmap))
    isl_die(bmap->ctx, isl_error_invalid,
      "basic map cannot be curried", goto error);
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
  bmap->dim = isl_space_curry(bmap->dim);
  if (!bmap->dim)
    goto error;
  bmap = isl_basic_map_mark_final(bmap);
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Given a map (A -> B) -> C, return the corresponding map
 * A -> (B -> C).
 */
__isl_give isl_map *isl_map_curry(__isl_take isl_map *map)
{
  return isl_map_change_space(map, &isl_map_can_curry,
            "map cannot be curried", &isl_space_curry);
}
 
/* Can isl_map_range_curry be applied to "map"?
 * That is, does it have a nested relation in its range,
 * the domain of which is itself a nested relation?
 */
isl_bool isl_map_can_range_curry(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
 
  return isl_space_can_range_curry(map->dim);
}
 
/* Given a map A -> ((B -> C) -> D), return the corresponding map
 * A -> (B -> (C -> D)).
 */
__isl_give isl_map *isl_map_range_curry(__isl_take isl_map *map)
{
  return isl_map_change_space(map, &isl_map_can_range_curry,
            "map range cannot be curried",
            &isl_space_range_curry);
}
 
/* Can we apply isl_basic_map_uncurry to "bmap"?
 * That is, does it have a nested relation in its domain?
 */
isl_bool isl_basic_map_can_uncurry(__isl_keep isl_basic_map *bmap)
{
  if (!bmap)
    return isl_bool_error;
 
  return isl_space_can_uncurry(bmap->dim);
}
 
/* Can we apply isl_map_uncurry to "map"?
 * That is, does it have a nested relation in its domain?
 */
isl_bool isl_map_can_uncurry(__isl_keep isl_map *map)
{
  if (!map)
    return isl_bool_error;
 
  return isl_space_can_uncurry(map->dim);
}
 
/* Given a basic map A -> (B -> C), return the corresponding basic map
 * (A -> B) -> C.
 */
__isl_give isl_basic_map *isl_basic_map_uncurry(__isl_take isl_basic_map *bmap)
{
 
  if (!bmap)
    return NULL;
 
  if (!isl_basic_map_can_uncurry(bmap))
    isl_die(bmap->ctx, isl_error_invalid,
      "basic map cannot be uncurried",
      return isl_basic_map_free(bmap));
  bmap = isl_basic_map_cow(bmap);
  if (!bmap)
    return NULL;
  bmap->dim = isl_space_uncurry(bmap->dim);
  if (!bmap->dim)
    return isl_basic_map_free(bmap);
  bmap = isl_basic_map_mark_final(bmap);
  return bmap;
}
 
/* Given a map A -> (B -> C), return the corresponding map
 * (A -> B) -> C.
 */
__isl_give isl_map *isl_map_uncurry(__isl_take isl_map *map)
{
  return isl_map_change_space(map, &isl_map_can_uncurry,
        "map cannot be uncurried", &isl_space_uncurry);
}
 
__isl_give isl_set *isl_set_equate(__isl_take isl_set *set,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  return isl_map_equate(set, type1, pos1, type2, pos2);
}
 
/* Construct a basic map where the given dimensions are equal to each other.
 */
static __isl_give isl_basic_map *equator(__isl_take isl_space *space,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *bmap = NULL;
  int i;
  isl_size total;
 
  total = isl_space_dim(space, isl_dim_all);
  if (total < 0 ||
      isl_space_check_range(space, type1, pos1, 1) < 0 ||
      isl_space_check_range(space, type2, pos2, 1) < 0)
    goto error;
 
  if (type1 == type2 && pos1 == pos2)
    return isl_basic_map_universe(space);
 
  bmap = isl_basic_map_alloc_space(isl_space_copy(space), 0, 1, 0);
  i = isl_basic_map_alloc_equality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->eq[i], 1 + total);
  pos1 += isl_basic_map_offset(bmap, type1);
  pos2 += isl_basic_map_offset(bmap, type2);
  isl_int_set_si(bmap->eq[i][pos1], -1);
  isl_int_set_si(bmap->eq[i][pos2], 1);
  bmap = isl_basic_map_finalize(bmap);
  isl_space_free(space);
  return bmap;
error:
  isl_space_free(space);
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Add a constraint imposing that the given two dimensions are equal.
 */
__isl_give isl_basic_map *isl_basic_map_equate(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *eq;
 
  eq = equator(isl_basic_map_get_space(bmap), type1, pos1, type2, pos2);
 
  bmap = isl_basic_map_intersect(bmap, eq);
 
  return bmap;
}
 
/* Add a constraint imposing that the given two dimensions are equal.
 */
__isl_give isl_map *isl_map_equate(__isl_take isl_map *map,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *bmap;
 
  bmap = equator(isl_map_get_space(map), type1, pos1, type2, pos2);
 
  map = isl_map_intersect(map, isl_map_from_basic_map(bmap));
 
  return map;
}
 
/* Add a constraint imposing that the given two dimensions have opposite values.
 */
__isl_give isl_map *isl_map_oppose(__isl_take isl_map *map,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *bmap = NULL;
  int i;
  isl_size total;
 
  if (isl_map_check_range(map, type1, pos1, 1) < 0)
    return isl_map_free(map);
  if (isl_map_check_range(map, type2, pos2, 1) < 0)
    return isl_map_free(map);
 
  total = isl_map_dim(map, isl_dim_all);
  if (total < 0)
    return isl_map_free(map);
  bmap = isl_basic_map_alloc_space(isl_map_get_space(map), 0, 1, 0);
  i = isl_basic_map_alloc_equality(bmap);
  if (i < 0)
    goto error;
  isl_seq_clr(bmap->eq[i], 1 + total);
  pos1 += isl_basic_map_offset(bmap, type1);
  pos2 += isl_basic_map_offset(bmap, type2);
  isl_int_set_si(bmap->eq[i][pos1], 1);
  isl_int_set_si(bmap->eq[i][pos2], 1);
  bmap = isl_basic_map_finalize(bmap);
 
  map = isl_map_intersect(map, isl_map_from_basic_map(bmap));
 
  return map;
error:
  isl_basic_map_free(bmap);
  isl_map_free(map);
  return NULL;
}
 
/* Construct a constraint imposing that the value of the first dimension is
 * greater than or equal to that of the second.
 */
static __isl_give isl_constraint *constraint_order_ge(
  __isl_take isl_space *space, enum isl_dim_type type1, int pos1,
  enum isl_dim_type type2, int pos2)
{
  isl_constraint *c;
 
  if (isl_space_check_range(space, type1, pos1, 1) < 0 ||
      isl_space_check_range(space, type2, pos2, 1) < 0)
    space = isl_space_free(space);
  if (!space)
    return NULL;
 
  c = isl_constraint_alloc_inequality(isl_local_space_from_space(space));
 
  if (type1 == type2 && pos1 == pos2)
    return c;
 
  c = isl_constraint_set_coefficient_si(c, type1, pos1, 1);
  c = isl_constraint_set_coefficient_si(c, type2, pos2, -1);
 
  return c;
}
 
/* Add a constraint imposing that the value of the first dimension is
 * greater than or equal to that of the second.
 */
__isl_give isl_basic_map *isl_basic_map_order_ge(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_constraint *c;
  isl_space *space;
 
  if (type1 == type2 && pos1 == pos2)
    return bmap;
  space = isl_basic_map_get_space(bmap);
  c = constraint_order_ge(space, type1, pos1, type2, pos2);
  bmap = isl_basic_map_add_constraint(bmap, c);
 
  return bmap;
}
 
/* Add a constraint imposing that the value of the first dimension is
 * greater than or equal to that of the second.
 */
__isl_give isl_map *isl_map_order_ge(__isl_take isl_map *map,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_constraint *c;
  isl_space *space;
 
  if (type1 == type2 && pos1 == pos2)
    return map;
  space = isl_map_get_space(map);
  c = constraint_order_ge(space, type1, pos1, type2, pos2);
  map = isl_map_add_constraint(map, c);
 
  return map;
}
 
/* Add a constraint imposing that the value of the first dimension is
 * less than or equal to that of the second.
 */
__isl_give isl_map *isl_map_order_le(__isl_take isl_map *map,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  return isl_map_order_ge(map, type2, pos2, type1, pos1);
}
 
/* Construct a basic map where the value of the first dimension is
 * greater than that of the second.
 */
static __isl_give isl_basic_map *greator(__isl_take isl_space *space,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *bmap = NULL;
  int i;
  isl_size total;
 
  if (isl_space_check_range(space, type1, pos1, 1) < 0 ||
      isl_space_check_range(space, type2, pos2, 1) < 0)
    goto error;
 
  if (type1 == type2 && pos1 == pos2)
    return isl_basic_map_empty(space);
 
  bmap = isl_basic_map_alloc_space(space, 0, 0, 1);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  i = isl_basic_map_alloc_inequality(bmap);
  if (total < 0 || i < 0)
    return isl_basic_map_free(bmap);
  isl_seq_clr(bmap->ineq[i], 1 + total);
  pos1 += isl_basic_map_offset(bmap, type1);
  pos2 += isl_basic_map_offset(bmap, type2);
  isl_int_set_si(bmap->ineq[i][pos1], 1);
  isl_int_set_si(bmap->ineq[i][pos2], -1);
  isl_int_set_si(bmap->ineq[i][0], -1);
  bmap = isl_basic_map_finalize(bmap);
 
  return bmap;
error:
  isl_space_free(space);
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Add a constraint imposing that the value of the first dimension is
 * greater than that of the second.
 */
__isl_give isl_basic_map *isl_basic_map_order_gt(__isl_take isl_basic_map *bmap,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *gt;
 
  gt = greator(isl_basic_map_get_space(bmap), type1, pos1, type2, pos2);
 
  bmap = isl_basic_map_intersect(bmap, gt);
 
  return bmap;
}
 
/* Add a constraint imposing that the value of the first dimension is
 * greater than that of the second.
 */
__isl_give isl_map *isl_map_order_gt(__isl_take isl_map *map,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  isl_basic_map *bmap;
 
  bmap = greator(isl_map_get_space(map), type1, pos1, type2, pos2);
 
  map = isl_map_intersect(map, isl_map_from_basic_map(bmap));
 
  return map;
}
 
/* Add a constraint imposing that the value of the first dimension is
 * smaller than that of the second.
 */
__isl_give isl_map *isl_map_order_lt(__isl_take isl_map *map,
  enum isl_dim_type type1, int pos1, enum isl_dim_type type2, int pos2)
{
  return isl_map_order_gt(map, type2, pos2, type1, pos1);
}
 
__isl_give isl_aff *isl_basic_map_get_div(__isl_keep isl_basic_map *bmap,
  int pos)
{
  isl_aff *div;
  isl_local_space *ls;
 
  if (!bmap)
    return NULL;
 
  if (!isl_basic_map_divs_known(bmap))
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "some divs are unknown", return NULL);
 
  ls = isl_basic_map_get_local_space(bmap);
  div = isl_local_space_get_div(ls, pos);
  isl_local_space_free(ls);
 
  return div;
}
 
__isl_give isl_aff *isl_basic_set_get_div(__isl_keep isl_basic_set *bset,
  int pos)
{
  return isl_basic_map_get_div(bset, pos);
}
 
/* Plug in "subs" for set dimension "pos" of "set".
 */
__isl_give isl_set *isl_set_substitute(__isl_take isl_set *set,
  unsigned pos, __isl_keep isl_aff *subs)
{
  isl_multi_aff *ma;
 
  if (set && isl_set_plain_is_empty(set))
    return set;
 
  ma = isl_multi_aff_identity_on_domain_space(isl_set_get_space(set));
  ma = isl_multi_aff_set_aff(ma, pos, isl_aff_copy(subs));
  return isl_set_preimage_multi_aff(set, ma);
}
 
/* Check if the range of "ma" is compatible with the domain or range
 * (depending on "type") of "bmap".
 */
static isl_stat check_basic_map_compatible_range_multi_aff(
  __isl_keep isl_basic_map *bmap, enum isl_dim_type type,
  __isl_keep isl_multi_aff *ma)
{
  isl_bool m;
  isl_space *ma_space;
 
  ma_space = isl_multi_aff_get_space(ma);
 
  m = isl_space_has_equal_params(bmap->dim, ma_space);
  if (m < 0)
    goto error;
  if (!m)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "parameters don't match", goto error);
  m = isl_space_tuple_is_equal(bmap->dim, type, ma_space, isl_dim_out);
  if (m < 0)
    goto error;
  if (!m)
    isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
      "spaces don't match", goto error);
 
  isl_space_free(ma_space);
  return isl_stat_ok;
error:
  isl_space_free(ma_space);
  return isl_stat_error;
}
 
/* Copy the divs from "ma" to "bmap", adding zeros for the "n_before"
 * coefficients before the transformed range of dimensions,
 * the "n_after" coefficients after the transformed range of dimensions
 * and the coefficients of the other divs in "bmap".
 */
static __isl_give isl_basic_map *set_ma_divs(__isl_take isl_basic_map *bmap,
  __isl_keep isl_multi_aff *ma, int n_before, int n_after, int n_div)
{
  int i;
  isl_size n_param;
  isl_size n_set;
  isl_local_space *ls;
 
  if (n_div == 0)
    return bmap;
 
  ls = isl_aff_get_domain_local_space(ma->u.p[0]);
  n_param = isl_local_space_dim(ls, isl_dim_param);
  n_set = isl_local_space_dim(ls, isl_dim_set);
  if (n_param < 0 || n_set < 0)
    return isl_basic_map_free(bmap);
 
  for (i = 0; i < n_div; ++i) {
    int o_bmap = 0, o_ls = 0;
 
    isl_seq_cpy(bmap->div[i], ls->div->row[i], 1 + 1 + n_param);
    o_bmap += 1 + 1 + n_param;
    o_ls += 1 + 1 + n_param;
    isl_seq_clr(bmap->div[i] + o_bmap, n_before);
    o_bmap += n_before;
    isl_seq_cpy(bmap->div[i] + o_bmap,
          ls->div->row[i] + o_ls, n_set);
    o_bmap += n_set;
    o_ls += n_set;
    isl_seq_clr(bmap->div[i] + o_bmap, n_after);
    o_bmap += n_after;
    isl_seq_cpy(bmap->div[i] + o_bmap,
          ls->div->row[i] + o_ls, n_div);
    o_bmap += n_div;
    o_ls += n_div;
    isl_seq_clr(bmap->div[i] + o_bmap, bmap->n_div - n_div);
    bmap = isl_basic_map_add_div_constraints(bmap, i);
    if (!bmap)
      goto error;
  }
 
  isl_local_space_free(ls);
  return bmap;
error:
  isl_local_space_free(ls);
  return isl_basic_map_free(bmap);
}
 
/* How many stride constraints does "ma" enforce?
 * That is, how many of the affine expressions have a denominator
 * different from one?
 */
static int multi_aff_strides(__isl_keep isl_multi_aff *ma)
{
  int i;
  int strides = 0;
 
  for (i = 0; i < ma->n; ++i)
    if (!isl_int_is_one(ma->u.p[i]->v->el[0]))
      strides++;
 
  return strides;
}
 
/* For each affine expression in ma of the form
 *
 *  x_i = (f_i y + h_i)/m_i
 *
 * with m_i different from one, add a constraint to "bmap"
 * of the form
 *
 *  f_i y + h_i = m_i alpha_i
 *
 * with alpha_i an additional existentially quantified variable.
 *
 * The input variables of "ma" correspond to a subset of the variables
 * of "bmap".  There are "n_before" variables in "bmap" before this
 * subset and "n_after" variables after this subset.
 * The integer divisions of the affine expressions in "ma" are assumed
 * to have been aligned.  There are "n_div_ma" of them and
 * they appear first in "bmap", straight after the "n_after" variables.
 */
static __isl_give isl_basic_map *add_ma_strides(
  __isl_take isl_basic_map *bmap, __isl_keep isl_multi_aff *ma,
  int n_before, int n_after, int n_div_ma)
{
  int i, k;
  int div;
  isl_size total;
  isl_size n_param;
  isl_size n_in;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  n_param = isl_multi_aff_dim(ma, isl_dim_param);
  n_in = isl_multi_aff_dim(ma, isl_dim_in);
  if (total < 0 || n_param < 0 || n_in < 0)
    return isl_basic_map_free(bmap);
  for (i = 0; i < ma->n; ++i) {
    int o_bmap = 0, o_ma = 1;
 
    if (isl_int_is_one(ma->u.p[i]->v->el[0]))
      continue;
    div = isl_basic_map_alloc_div(bmap);
    k = isl_basic_map_alloc_equality(bmap);
    if (div < 0 || k < 0)
      goto error;
    isl_int_set_si(bmap->div[div][0], 0);
    isl_seq_cpy(bmap->eq[k] + o_bmap,
          ma->u.p[i]->v->el + o_ma, 1 + n_param);
    o_bmap += 1 + n_param;
    o_ma += 1 + n_param;
    isl_seq_clr(bmap->eq[k] + o_bmap, n_before);
    o_bmap += n_before;
    isl_seq_cpy(bmap->eq[k] + o_bmap,
          ma->u.p[i]->v->el + o_ma, n_in);
    o_bmap += n_in;
    o_ma += n_in;
    isl_seq_clr(bmap->eq[k] + o_bmap, n_after);
    o_bmap += n_after;
    isl_seq_cpy(bmap->eq[k] + o_bmap,
          ma->u.p[i]->v->el + o_ma, n_div_ma);
    o_bmap += n_div_ma;
    o_ma += n_div_ma;
    isl_seq_clr(bmap->eq[k] + o_bmap, 1 + total - o_bmap);
    isl_int_neg(bmap->eq[k][1 + total], ma->u.p[i]->v->el[0]);
    total++;
  }
 
  return bmap;
error:
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Replace the domain or range space (depending on "type) of "space" by "set".
 */
static __isl_give isl_space *isl_space_set(__isl_take isl_space *space,
  enum isl_dim_type type, __isl_take isl_space *set)
{
  if (type == isl_dim_in) {
    space = isl_space_range(space);
    space = isl_space_map_from_domain_and_range(set, space);
  } else {
    space = isl_space_domain(space);
    space = isl_space_map_from_domain_and_range(space, set);
  }
 
  return space;
}
 
/* Compute the preimage of the domain or range (depending on "type")
 * of "bmap" under the function represented by "ma".
 * In other words, plug in "ma" in the domain or range of "bmap".
 * The result is a basic map that lives in the same space as "bmap"
 * except that the domain or range has been replaced by
 * the domain space of "ma".
 *
 * If bmap is represented by
 *
 *  A(p) + S u + B x + T v + C(divs) >= 0,
 *
 * where u and x are input and output dimensions if type == isl_dim_out
 * while x and v are input and output dimensions if type == isl_dim_in,
 * and ma is represented by
 *
 *  x = D(p) + F(y) + G(divs')
 *
 * then the result is
 *
 *  A(p) + B D(p) + S u + B F(y) + T v + B G(divs') + C(divs) >= 0
 *
 * The divs in the input set are similarly adjusted.
 * In particular
 *
 *  floor((a_i(p) + s u + b_i x + t v + c_i(divs))/n_i)
 *
 * becomes
 *
 *  floor((a_i(p) + b_i D(p) + s u + b_i F(y) + t v +
 *    B_i G(divs') + c_i(divs))/n_i)
 *
 * If bmap is not a rational map and if F(y) involves any denominators
 *
 *  x_i = (f_i y + h_i)/m_i
 *
 * then additional constraints are added to ensure that we only
 * map back integer points.  That is we enforce
 *
 *  f_i y + h_i = m_i alpha_i
 *
 * with alpha_i an additional existentially quantified variable.
 *
 * We first copy over the divs from "ma".
 * Then we add the modified constraints and divs from "bmap".
 * Finally, we add the stride constraints, if needed.
 */
__isl_give isl_basic_map *isl_basic_map_preimage_multi_aff(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type,
  __isl_take isl_multi_aff *ma)
{
  int i, k;
  isl_space *space;
  isl_basic_map *res = NULL;
  isl_size n_before, n_after, n_div_bmap, n_div_ma;
  isl_int f, c1, c2, g;
  isl_bool rational;
  int strides;
 
  isl_int_init(f);
  isl_int_init(c1);
  isl_int_init(c2);
  isl_int_init(g);
 
  ma = isl_multi_aff_align_divs(ma);
  if (!bmap || !ma)
    goto error;
  if (check_basic_map_compatible_range_multi_aff(bmap, type, ma) < 0)
    goto error;
 
  if (type == isl_dim_in) {
    n_before = 0;
    n_after = isl_basic_map_dim(bmap, isl_dim_out);
  } else {
    n_before = isl_basic_map_dim(bmap, isl_dim_in);
    n_after = 0;
  }
  n_div_bmap = isl_basic_map_dim(bmap, isl_dim_div);
  n_div_ma = ma->n ? isl_aff_dim(ma->u.p[0], isl_dim_div) : 0;
  if (n_before < 0 || n_after < 0 || n_div_bmap < 0 || n_div_ma < 0)
    goto error;
 
  space = isl_multi_aff_get_domain_space(ma);
  space = isl_space_set(isl_basic_map_get_space(bmap), type, space);
  rational = isl_basic_map_is_rational(bmap);
  strides = rational ? 0 : multi_aff_strides(ma);
  res = isl_basic_map_alloc_space(space, n_div_ma + n_div_bmap + strides,
          bmap->n_eq + strides, bmap->n_ineq + 2 * n_div_ma);
  if (rational)
    res = isl_basic_map_set_rational(res);
 
  for (i = 0; i < n_div_ma + n_div_bmap; ++i)
    if (isl_basic_map_alloc_div(res) < 0)
      goto error;
 
  res = set_ma_divs(res, ma, n_before, n_after, n_div_ma);
  if (!res)
    goto error;
 
  for (i = 0; i < bmap->n_eq; ++i) {
    k = isl_basic_map_alloc_equality(res);
    if (k < 0)
      goto error;
    if (isl_seq_preimage(res->eq[k], bmap->eq[i], ma, n_before,
            n_after, n_div_ma, n_div_bmap,
            f, c1, c2, g, 0) < 0)
      goto error;
  }
 
  for (i = 0; i < bmap->n_ineq; ++i) {
    k = isl_basic_map_alloc_inequality(res);
    if (k < 0)
      goto error;
    if (isl_seq_preimage(res->ineq[k], bmap->ineq[i], ma, n_before,
            n_after, n_div_ma, n_div_bmap,
            f, c1, c2, g, 0) < 0)
      goto error;
  }
 
  for (i = 0; i < bmap->n_div; ++i) {
    if (isl_int_is_zero(bmap->div[i][0])) {
      isl_int_set_si(res->div[n_div_ma + i][0], 0);
      continue;
    }
    if (isl_seq_preimage(res->div[n_div_ma + i], bmap->div[i], ma,
            n_before, n_after, n_div_ma, n_div_bmap,
            f, c1, c2, g, 1) < 0)
      goto error;
  }
 
  if (strides)
    res = add_ma_strides(res, ma, n_before, n_after, n_div_ma);
 
  isl_int_clear(f);
  isl_int_clear(c1);
  isl_int_clear(c2);
  isl_int_clear(g);
  isl_basic_map_free(bmap);
  isl_multi_aff_free(ma);
  res = isl_basic_map_simplify(res);
  return isl_basic_map_finalize(res);
error:
  isl_int_clear(f);
  isl_int_clear(c1);
  isl_int_clear(c2);
  isl_int_clear(g);
  isl_basic_map_free(bmap);
  isl_multi_aff_free(ma);
  isl_basic_map_free(res);
  return NULL;
}
 
/* Compute the preimage of "bset" under the function represented by "ma".
 * In other words, plug in "ma" in "bset".  The result is a basic set
 * that lives in the domain space of "ma".
 */
__isl_give isl_basic_set *isl_basic_set_preimage_multi_aff(
  __isl_take isl_basic_set *bset, __isl_take isl_multi_aff *ma)
{
  return isl_basic_map_preimage_multi_aff(bset, isl_dim_set, ma);
}
 
/* Compute the preimage of the domain of "bmap" under the function
 * represented by "ma".
 * In other words, plug in "ma" in the domain of "bmap".
 * The result is a basic map that lives in the same space as "bmap"
 * except that the domain has been replaced by the domain space of "ma".
 */
__isl_give isl_basic_map *isl_basic_map_preimage_domain_multi_aff(
  __isl_take isl_basic_map *bmap, __isl_take isl_multi_aff *ma)
{
  return isl_basic_map_preimage_multi_aff(bmap, isl_dim_in, ma);
}
 
/* Compute the preimage of the range of "bmap" under the function
 * represented by "ma".
 * In other words, plug in "ma" in the range of "bmap".
 * The result is a basic map that lives in the same space as "bmap"
 * except that the range has been replaced by the domain space of "ma".
 */
__isl_give isl_basic_map *isl_basic_map_preimage_range_multi_aff(
  __isl_take isl_basic_map *bmap, __isl_take isl_multi_aff *ma)
{
  return isl_basic_map_preimage_multi_aff(bmap, isl_dim_out, ma);
}
 
/* Check if the range of "ma" is compatible with the domain or range
 * (depending on "type") of "map".
 * Return isl_stat_error if anything is wrong.
 */
static isl_stat check_map_compatible_range_multi_aff(
  __isl_keep isl_map *map, enum isl_dim_type type,
  __isl_keep isl_multi_aff *ma)
{
  isl_bool m;
  isl_space *ma_space;
 
  ma_space = isl_multi_aff_get_space(ma);
  m = isl_map_space_tuple_is_equal(map, type, ma_space, isl_dim_out);
  isl_space_free(ma_space);
  if (m < 0)
    return isl_stat_error;
  if (!m)
    isl_die(isl_map_get_ctx(map), isl_error_invalid,
      "spaces don't match", return isl_stat_error);
  return isl_stat_ok;
}
 
/* Compute the preimage of the domain or range (depending on "type")
 * of "map" under the function represented by "ma".
 * In other words, plug in "ma" in the domain or range of "map".
 * The result is a map that lives in the same space as "map"
 * except that the domain or range has been replaced by
 * the domain space of "ma".
 *
 * The parameters are assumed to have been aligned.
 */
static __isl_give isl_map *map_preimage_multi_aff(__isl_take isl_map *map,
  enum isl_dim_type type, __isl_take isl_multi_aff *ma)
{
  int i;
  isl_space *space;
 
  map = isl_map_cow(map);
  ma = isl_multi_aff_align_divs(ma);
  if (!map || !ma)
    goto error;
  if (check_map_compatible_range_multi_aff(map, type, ma) < 0)
    goto error;
 
  for (i = 0; i < map->n; ++i) {
    map->p[i] = isl_basic_map_preimage_multi_aff(map->p[i], type,
              isl_multi_aff_copy(ma));
    if (!map->p[i])
      goto error;
  }
 
  space = isl_multi_aff_get_domain_space(ma);
  space = isl_space_set(isl_map_get_space(map), type, space);
 
  isl_space_free(isl_map_take_space(map));
  map = isl_map_restore_space(map, space);
  if (!map)
    goto error;
 
  isl_multi_aff_free(ma);
  if (map->n > 1)
    ISL_F_CLR(map, ISL_MAP_DISJOINT);
  ISL_F_CLR(map, ISL_SET_NORMALIZED);
  return map;
error:
  isl_multi_aff_free(ma);
  isl_map_free(map);
  return NULL;
}
 
/* Compute the preimage of the domain or range (depending on "type")
 * of "map" under the function represented by "ma".
 * In other words, plug in "ma" in the domain or range of "map".
 * The result is a map that lives in the same space as "map"
 * except that the domain or range has been replaced by
 * the domain space of "ma".
 */
__isl_give isl_map *isl_map_preimage_multi_aff(__isl_take isl_map *map,
  enum isl_dim_type type, __isl_take isl_multi_aff *ma)
{
  isl_bool aligned;
 
  if (!map || !ma)
    goto error;
 
  aligned = isl_map_space_has_equal_params(map, ma->space);
  if (aligned < 0)
    goto error;
  if (aligned)
    return map_preimage_multi_aff(map, type, ma);
 
  if (isl_map_check_named_params(map) < 0)
    goto error;
  if (!isl_space_has_named_params(ma->space))
    isl_die(map->ctx, isl_error_invalid,
      "unaligned unnamed parameters", goto error);
  map = isl_map_align_params(map, isl_multi_aff_get_space(ma));
  ma = isl_multi_aff_align_params(ma, isl_map_get_space(map));
 
  return map_preimage_multi_aff(map, type, ma);
error:
  isl_multi_aff_free(ma);
  return isl_map_free(map);
}
 
/* Compute the preimage of "set" under the function represented by "ma".
 * In other words, plug in "ma" in "set".  The result is a set
 * that lives in the domain space of "ma".
 */
__isl_give isl_set *isl_set_preimage_multi_aff(__isl_take isl_set *set,
  __isl_take isl_multi_aff *ma)
{
  return isl_map_preimage_multi_aff(set, isl_dim_set, ma);
}
 
/* Compute the preimage of the domain of "map" under the function
 * represented by "ma".
 * In other words, plug in "ma" in the domain of "map".
 * The result is a map that lives in the same space as "map"
 * except that the domain has been replaced by the domain space of "ma".
 */
__isl_give isl_map *isl_map_preimage_domain_multi_aff(__isl_take isl_map *map,
  __isl_take isl_multi_aff *ma)
{
  return isl_map_preimage_multi_aff(map, isl_dim_in, ma);
}
 
/* Compute the preimage of the range of "map" under the function
 * represented by "ma".
 * In other words, plug in "ma" in the range of "map".
 * The result is a map that lives in the same space as "map"
 * except that the range has been replaced by the domain space of "ma".
 */
__isl_give isl_map *isl_map_preimage_range_multi_aff(__isl_take isl_map *map,
  __isl_take isl_multi_aff *ma)
{
  return isl_map_preimage_multi_aff(map, isl_dim_out, ma);
}
 
/* Compute the preimage of "map" under the function represented by "pma".
 * In other words, plug in "pma" in the domain or range of "map".
 * The result is a map that lives in the same space as "map",
 * except that the space of type "type" has been replaced by
 * the domain space of "pma".
 *
 * The parameters of "map" and "pma" are assumed to have been aligned.
 */
static __isl_give isl_map *isl_map_preimage_pw_multi_aff_aligned(
  __isl_take isl_map *map, enum isl_dim_type type,
  __isl_take isl_pw_multi_aff *pma)
{
  int i;
  isl_map *res;
 
  if (!pma)
    goto error;
 
  if (pma->n == 0) {
    isl_space *space;
 
    space = isl_pw_multi_aff_get_domain_space(pma);
    isl_pw_multi_aff_free(pma);
    space = isl_space_set(isl_map_get_space(map), type, space);
    isl_map_free(map);
    return isl_map_empty(space);
  }
 
  res = isl_map_preimage_multi_aff(isl_map_copy(map), type,
          isl_multi_aff_copy(pma->p[0].maff));
  if (type == isl_dim_in)
    res = isl_map_intersect_domain(res,
            isl_map_copy(pma->p[0].set));
  else
    res = isl_map_intersect_range(res,
            isl_map_copy(pma->p[0].set));
 
  for (i = 1; i < pma->n; ++i) {
    isl_map *res_i;
 
    res_i = isl_map_preimage_multi_aff(isl_map_copy(map), type,
          isl_multi_aff_copy(pma->p[i].maff));
    if (type == isl_dim_in)
      res_i = isl_map_intersect_domain(res_i,
            isl_map_copy(pma->p[i].set));
    else
      res_i = isl_map_intersect_range(res_i,
            isl_map_copy(pma->p[i].set));
    res = isl_map_union(res, res_i);
  }
 
  isl_pw_multi_aff_free(pma);
  isl_map_free(map);
  return res;
error:
  isl_pw_multi_aff_free(pma);
  isl_map_free(map);
  return NULL;
}
 
/* Compute the preimage of "map" under the function represented by "pma".
 * In other words, plug in "pma" in the domain or range of "map".
 * The result is a map that lives in the same space as "map",
 * except that the space of type "type" has been replaced by
 * the domain space of "pma".
 */
__isl_give isl_map *isl_map_preimage_pw_multi_aff(__isl_take isl_map *map,
  enum isl_dim_type type, __isl_take isl_pw_multi_aff *pma)
{
  isl_bool aligned;
 
  if (!map || !pma)
    goto error;
 
  aligned = isl_map_space_has_equal_params(map, pma->dim);
  if (aligned < 0)
    goto error;
  if (aligned)
    return isl_map_preimage_pw_multi_aff_aligned(map, type, pma);
 
  if (isl_map_check_named_params(map) < 0)
    goto error;
  if (isl_pw_multi_aff_check_named_params(pma) < 0)
    goto error;
  map = isl_map_align_params(map, isl_pw_multi_aff_get_space(pma));
  pma = isl_pw_multi_aff_align_params(pma, isl_map_get_space(map));
 
  return isl_map_preimage_pw_multi_aff_aligned(map, type, pma);
error:
  isl_pw_multi_aff_free(pma);
  return isl_map_free(map);
}
 
/* Compute the preimage of "set" under the function represented by "pma".
 * In other words, plug in "pma" in "set".  The result is a set
 * that lives in the domain space of "pma".
 */
__isl_give isl_set *isl_set_preimage_pw_multi_aff(__isl_take isl_set *set,
  __isl_take isl_pw_multi_aff *pma)
{
  return isl_map_preimage_pw_multi_aff(set, isl_dim_set, pma);
}
 
/* Compute the preimage of the domain of "map" under the function
 * represented by "pma".
 * In other words, plug in "pma" in the domain of "map".
 * The result is a map that lives in the same space as "map",
 * except that domain space has been replaced by the domain space of "pma".
 */
__isl_give isl_map *isl_map_preimage_domain_pw_multi_aff(
  __isl_take isl_map *map, __isl_take isl_pw_multi_aff *pma)
{
  return isl_map_preimage_pw_multi_aff(map, isl_dim_in, pma);
}
 
/* Compute the preimage of the range of "map" under the function
 * represented by "pma".
 * In other words, plug in "pma" in the range of "map".
 * The result is a map that lives in the same space as "map",
 * except that range space has been replaced by the domain space of "pma".
 */
__isl_give isl_map *isl_map_preimage_range_pw_multi_aff(
  __isl_take isl_map *map, __isl_take isl_pw_multi_aff *pma)
{
  return isl_map_preimage_pw_multi_aff(map, isl_dim_out, pma);
}
 
/* Compute the preimage of "map" under the function represented by "mpa".
 * In other words, plug in "mpa" in the domain or range of "map".
 * The result is a map that lives in the same space as "map",
 * except that the space of type "type" has been replaced by
 * the domain space of "mpa".
 *
 * If the map does not involve any constraints that refer to the
 * dimensions of the substituted space, then the only possible
 * effect of "mpa" on the map is to map the space to a different space.
 * We create a separate isl_multi_aff to effectuate this change
 * in order to avoid spurious splitting of the map along the pieces
 * of "mpa".
 * If "mpa" has a non-trivial explicit domain, however,
 * then the full substitution should be performed.
 */
__isl_give isl_map *isl_map_preimage_multi_pw_aff(__isl_take isl_map *map,
  enum isl_dim_type type, __isl_take isl_multi_pw_aff *mpa)
{
  isl_size n;
  isl_bool full;
  isl_pw_multi_aff *pma;
 
  n = isl_map_dim(map, type);
  if (n < 0 || !mpa)
    goto error;
 
  full = isl_map_involves_dims(map, type, 0, n);
  if (full >= 0 && !full)
    full = isl_multi_pw_aff_has_non_trivial_domain(mpa);
  if (full < 0)
    goto error;
  if (!full) {
    isl_space *space;
    isl_multi_aff *ma;
 
    space = isl_multi_pw_aff_get_space(mpa);
    isl_multi_pw_aff_free(mpa);
    ma = isl_multi_aff_zero(space);
    return isl_map_preimage_multi_aff(map, type, ma);
  }
 
  pma = isl_pw_multi_aff_from_multi_pw_aff(mpa);
  return isl_map_preimage_pw_multi_aff(map, type, pma);
error:
  isl_map_free(map);
  isl_multi_pw_aff_free(mpa);
  return NULL;
}
 
/* Compute the preimage of "map" under the function represented by "mpa".
 * In other words, plug in "mpa" in the domain "map".
 * The result is a map that lives in the same space as "map",
 * except that domain space has been replaced by the domain space of "mpa".
 */
__isl_give isl_map *isl_map_preimage_domain_multi_pw_aff(
  __isl_take isl_map *map, __isl_take isl_multi_pw_aff *mpa)
{
  return isl_map_preimage_multi_pw_aff(map, isl_dim_in, mpa);
}
 
/* Compute the preimage of "set" by the function represented by "mpa".
 * In other words, plug in "mpa" in "set".
 */
__isl_give isl_set *isl_set_preimage_multi_pw_aff(__isl_take isl_set *set,
  __isl_take isl_multi_pw_aff *mpa)
{
  return isl_map_preimage_multi_pw_aff(set, isl_dim_set, mpa);
}
 
/* Given that inequality "ineq" of "bmap" expresses an upper bound
 * on the output dimension "pos" in terms of the parameters,
 * the input dimensions and possibly some integer divisions,
 * but not any other output dimensions, extract this upper bound
 * as a function of all dimensions (with zero coefficients
 * for the output dimensions).
 *
 * That is, the inequality is of the form
 *
 *  e(...) + c - m x >= 0
 *
 * where e does not depend on any other output dimensions.
 * Return (e(...) + c) / m, with the denominator m in the first position.
 */
__isl_give isl_vec *isl_basic_map_inequality_extract_output_upper_bound(
  __isl_keep isl_basic_map *bmap, int ineq, int pos)
{
  isl_ctx *ctx;
  isl_size v_out, total;
 
  v_out = isl_basic_map_var_offset(bmap, isl_dim_out);
  total = isl_basic_map_dim(bmap, isl_dim_all);
  if (v_out < 0 || total < 0)
    return NULL;
  ctx = isl_basic_map_get_ctx(bmap);
  return extract_bound_from_constraint(ctx, bmap->ineq[ineq],
              total, v_out + pos);
}
 
/* Is constraint "c" of "bmap" of the form
 *
 *  e(...) + c1 - m x >= 0
 *
 * or
 *
 *  -e(...) + c2 + m x >= 0
 *
 * where m > 1 and e does not involve any other output variables?
 *
 * "v_out" is the offset to the output variables.
 * "d" is the position of x among the output variables.
 * "v_div" is the offset to the local variables.
 * "total" is the total number of variables.
 *
 * Since the purpose of this function is to use the constraint
 * to express the output variable as an integer division,
 * do not allow the constraint to involve any local variables
 * that do not have an explicit representation.
 */
static isl_bool is_potential_div_constraint(__isl_keep isl_basic_map *bmap,
  isl_int *c, int v_out, int d, int v_div, int total)
{
  int i = 0;
 
  if (isl_int_is_zero(c[1 + v_out + d]))
    return isl_bool_false;
  if (isl_int_is_one(c[1 + v_out + d]))
    return isl_bool_false;
  if (isl_int_is_negone(c[1 + v_out + d]))
    return isl_bool_false;
  if (isl_seq_any_non_zero(c + 1 + v_out, d))
    return isl_bool_false;
  if (isl_seq_any_non_zero(c + 1 + v_out + d + 1, v_div - (v_out + d + 1)))
    return isl_bool_false;
  for (i = 0; v_div + i < total; ++i) {
    isl_bool known, involves;
 
    if (isl_int_is_zero(c[1 + v_div + i]))
      continue;
    known = isl_basic_map_div_is_known(bmap, i);
    if (known < 0 || !known)
      return known;
    involves = div_involves_vars(bmap, i, v_out, v_div - v_out);
    if (involves < 0 || involves)
      return isl_bool_not(involves);
  }
  return isl_bool_true;
}
 
/* Look for a pair of constraints
 *
 *  e(...) + c1 - m x >= 0    i.e.,   m x <= e(...) + c1
 *
 * and
 *
 *  -e(...) + c2 + m x >= 0   i.e.,   m x >= e(...) - c2
 *
 * that express that the output dimension x at position "pos"
 * is some integer division of an expression in terms of the parameters,
 * input dimensions and integer divisions.
 * If such a pair can be found, then return the index
 * of the upper bound constraint, m x <= e(...) + c1.
 * Otherwise, return an index beyond the number of constraints.
 *
 * The constraints of "bmap" are assumed to have been sorted.
 *
 * In order for the constraints above to express an integer division,
 * m needs to be greater than 1 and such that
 *
 *  c1 + c2 < m     i.e.,   -c2 >= c1 - (m - 1)
 *
 * In particular, this ensures that
 *
 *  x = floor((e(...) + c1) / m)
 */
isl_size isl_basic_map_find_output_upper_div_constraint(
  __isl_keep isl_basic_map *bmap, int pos)
{
  int i;
  isl_size j;
  isl_size n_ineq;
  isl_size v_out, v_div;
  isl_size total;
  isl_int sum;
 
  total = isl_basic_map_dim(bmap, isl_dim_all);
  v_out = isl_basic_map_var_offset(bmap, isl_dim_out);
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  n_ineq = isl_basic_map_n_inequality(bmap);
  if (total < 0 || v_out < 0 || v_div < 0 || n_ineq < 0)
    return isl_size_error;
 
  isl_int_init(sum);
  for (i = 0; i < n_ineq; ++i) {
    isl_bool potential;
 
    potential = is_potential_div_constraint(bmap, bmap->ineq[i],
            v_out, pos, v_div, total);
    if (potential < 0)
      goto error;
    if (!potential)
      continue;
 
    j = find_later_constraint_in_pair(bmap, i, v_out + pos, total,
          bmap->ineq[i][1 + v_out + pos], &sum);
    if (j < 0)
      goto error;
    if (j < n_ineq)
      break;
  }
  isl_int_clear(sum);
 
  if (i >= n_ineq)
    return n_ineq;
  if (isl_int_is_pos(bmap->ineq[j][1 + v_out + pos]))
    return i;
  else
    return j;
error:
  isl_int_clear(sum);
  return isl_size_error;
}
 
/* Look for a pair of constraints
 *
 *  -g(x) + i >= 0
 *   g(x) - i + d >= 0
 *
 * in "bmap" on the output dimension at position "pos" such that
 * g(x) is an expression in the parameters and input dimensions, and
 * d < "n".
 * Return the index of the first constraint if such a pair can be found.
 * Otherwise, return an index beyond the number of inequality constraints.
 *
 * The constraints are assumed to have been sorted.
 */
static isl_size find_output_lower_mod_constraint(__isl_keep isl_basic_map *bmap,
  int pos, isl_int n)
{
  int i;
  isl_size n_ineq;
  isl_size v_out, n_out;
  isl_size v_div, n_div;
  isl_size j;
  isl_int tmp;
 
  n_ineq = isl_basic_map_n_inequality(bmap);
  v_out = isl_basic_map_var_offset(bmap, isl_dim_out);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_ineq < 0 || v_out < 0 || n_out < 0 || v_div < 0 || n_div < 0)
    return isl_size_error;
 
  isl_int_init(tmp);
  for (i = n_ineq - 1; i >= 0; --i) {
    if (!isl_int_is_one(bmap->ineq[i][1 + v_out + pos]) &&
        !isl_int_is_negone(bmap->ineq[i][1 + v_out + pos]))
      continue;
    if (isl_seq_any_non_zero(bmap->ineq[i] + 1 + v_div, n_div))
      continue;
    if (isl_seq_any_non_zero(bmap->ineq[i] + 1 + v_out, pos))
      continue;
    if (isl_seq_any_non_zero(bmap->ineq[i] + 1 + v_out + pos + 1,
              n_out - (pos + 1)))
      continue;
    j = find_earlier_constraint_in_pair(bmap, i, v_out + pos, v_div,
                n, &tmp);
    if (j >= n_ineq)
      continue;
    isl_int_clear(tmp);
    if (j < 0)
      return j;
    if (isl_int_is_one(bmap->ineq[i][1 + v_out + pos]))
      return i;
    return j;
  }
 
  isl_int_clear(tmp);
  return n_ineq;
}
 
/* Turn "bmap" into a basic set for constructing an affine expression
 * that can later be plugged into an output dimension of "bmap".
 * "is_set" is set if "bmap" is actually a basic set already.
 *
 * If "bmap" is a basic set already, then simply cast it.
 * Otherwise, wrap "bmap" into a basic set.
 */
static __isl_give isl_basic_set *wrap_for_plug_in(
  __isl_take isl_basic_map *bmap, int is_set)
{
  if (is_set)
    return bset_from_bmap(bmap);
  else
    return isl_basic_map_wrap(bmap);
}
 
/* Given an affine expression "aff" that was constructed on top of
 * the result of wrap_for_plug_in and that does not depend on the output space,
 * project out this output space.
 * "is_set" is the same as in the call to wrap_for_plug_in.
 *
 * If "is_set" is set then the output space is actually the set space
 * of the original basic set and this appears as the domain of "aff".
 * Otherwise, the output space appears as the range in the nested domain.
 */
static __isl_give isl_aff *unwrap_plug_in(__isl_take isl_aff *aff, int is_set)
{
  if (is_set)
    return isl_aff_project_domain_on_params(aff);
  else
    return isl_aff_domain_factor_domain(aff);
}
 
/* Given that equality "eq" of "bset" expresses
 * the variable at position "pos" in terms of the other variables,
 * extract this expression as a function of those other variables,
 * excluding any local variables.
 */
static __isl_give isl_aff *extract_expr_aff(
  __isl_keep isl_basic_set *bset, int eq, int pos)
{
  if (!bset)
    return NULL;
  return extract_aff(bset, bset->eq[eq], pos);
}
 
/* Given an integer division "div" of the form
 *
 *  (f(x) + a i)//m
 *
 * with i the variable at position "pos" and f not involving
 * any local variables, return the expression
 *
 *  -f(x)/a
 */
static __isl_give isl_aff *extract_div_expr_aff(
  __isl_keep isl_basic_set *bset, int div, int pos)
{
  if (!bset)
    return NULL;
  return extract_aff(bset, bset->div[div] + 1, pos);
}
 
/* Given the presence in "bmap" of an equality constraint "eq"
 *
 *  f(x) + t m i + m n h(y) = 0
 *
 * and a pair of inequality constraints
 *
 *  -g(x) + i >= 0      ("lower")
 *   g(x) - i + d >= 0
 *
 * where i is the output dimension at position "pos",
 * f(x) and g(x) are expressions in the parameters and
 * input dimensions (if any),
 * h(y) is an expression in the other output dimensions,
 * t is +1 or -1, and
 * d < "n",
 * return the expression
 *
 *  (-t f(x)/m - g(x)) mod n + g(x)
 *
 * The expression is first constructed in terms of the wrapped space of "bmap".
 * Since this expression does not depend on the original output dimensions,
 * they can be removed, resulting in an expression in terms
 * of the input dimensions.
 * If "bmap" is actually a set, then the resulting expression has no domain.
 *
 * Also note that the "f" variable contains "-t (f(x)/m + n h(y))"
 * but the "n h(y)" part is removed by taking the modulo with respect to n.
 */
static __isl_give isl_aff *construct_mod(__isl_keep isl_basic_map *bmap,
  int pos, int eq, int lower, isl_int n)
{
  isl_ctx *ctx;
  isl_basic_set *bset;
  isl_aff *f, *g, *mod;
  isl_val *v;
  isl_bool is_set;
 
  is_set = isl_basic_map_is_set(bmap);
  if (is_set < 0)
    return NULL;
  ctx = isl_basic_map_get_ctx(bmap);
 
  bset = wrap_for_plug_in(isl_basic_map_copy(bmap), is_set);
  g = extract_lower_bound_aff(bset, lower, pos);
  f = extract_expr_aff(bset, eq, pos);
  isl_basic_set_free(bset);
 
  mod = isl_aff_sub(f, isl_aff_copy(g));
  v = isl_val_int_from_isl_int(ctx, n);
  mod = isl_aff_mod_val(mod, v);
  mod = isl_aff_add(mod, g);
  mod = unwrap_plug_in(mod, is_set);
 
  return mod;
}
 
/* Look for a combination of constraints in "bmap" (including
 * an equality constraint) that ensure
 * that output dimension "pos" is equal to some modulo expression
 * in the parameters and input dimensions and
 * return this expression if found.
 *
 * The constraints are assumed to have been sorted.
 *
 * In particular look for an equality constraint
 *
 *  f(x) + t m i + m n h(y) = 0
 *
 * and a pair of inequality constraints
 *
 *  -g(x) + i >= 0
 *   g(x) - i + d >= 0
 *
 * where f(x) and g(x) are expressions in the parameters and input dimensions,
 * h(y) is an expression in local variables and other output dimensions,
 * t is +1 or -1, and
 * d < n.
 *
 * If such a combination of constraints can be found
 * then
 *
 *  i = -t f(x)/m - t n h(y)
 *  i - g(x) = -t f(x)/m - t n h(y) - g(x)
 *
 * and so, because 0 <= i - g(x) <= d < n,
 *
 *  i - g(x) = (-t f(x)/m - t n h(y) - g(x)) mod n
 *           = (-t f(x)/m - g(x)) mod n
 *
 * That is,
 *
 *  i = (-t f(x)/m - g(x)) mod n + g(x)
 */
static __isl_give isl_maybe_isl_aff isl_basic_map_try_find_output_mod_eq(
  __isl_keep isl_basic_map *bmap, int pos)
{
  int i, j;
  isl_size n_eq, n_ineq;
  isl_size v_out, n_out;
  isl_size v_div, n_div;
  isl_size lower;
  isl_int gcd;
  isl_maybe_isl_aff res = { isl_bool_false, NULL };
 
  n_eq = isl_basic_map_n_equality(bmap);
  n_ineq = isl_basic_map_n_inequality(bmap);
  v_out = isl_basic_map_var_offset(bmap, isl_dim_out);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_eq < 0 || n_ineq < 0 ||
      v_out < 0 || n_out < 0 || v_div < 0 || n_div < 0)
    goto error;
  if (n_eq == 0 || n_ineq < 2 || n_out == 1)
    return res;
 
  isl_int_init(gcd);
  for (i = 0; i < n_eq; ++i) {
    if (isl_int_is_zero(bmap->eq[i][1 + v_out + pos]))
      continue;
    isl_seq_gcd(bmap->eq[i] + 1 + v_div, n_div, &gcd);
    for (j = 0; j < n_out; ++j) {
      if (j == pos)
        continue;
      isl_int_gcd(gcd, gcd, bmap->eq[i][1 + v_out + j]);
    }
    if (!isl_int_abs_gt(gcd, bmap->eq[i][1 + v_out + pos]))
      continue;
    if (!isl_int_is_divisible_by(gcd, bmap->eq[i][1 + v_out + pos]))
      continue;
    isl_int_divexact(gcd, gcd, bmap->eq[i][1 + v_out + pos]);
    isl_int_abs(gcd, gcd);
    lower = find_output_lower_mod_constraint(bmap, pos, gcd);
    if (lower >= n_ineq)
      continue;
    res.valid = isl_bool_true;
    if (lower >= 0)
      res.value = construct_mod(bmap, v_out + pos, i,
            lower, gcd);
    if (!res.value)
      res.valid = isl_bool_error;
    isl_int_clear(gcd);
    return res;
  }
 
  isl_int_clear(gcd);
  return res;
error:
  res.valid = isl_bool_error;
  return res;
}
 
/* Given that the integer division "div" of "bmap" is of the form
 *
 *  (f(x) + t m i)//(m n)
 *
 * with t equal to 1 or -1 and n positive,
 * while the inequality constraint "lower" is of the form
 *
 *  -g(x) + i >= 0
 *
 * with neither involving any local variables or output dimensions other than i,
 * construct the expression
 *
 *  (t (n - 1) - t f(x)//m - g(x)) mod n + g(x)
 *
 * "pos" is the position of the variable i.
 * "t" and "n" are the values t and n.
 *
 * The expression is first constructed in terms of the wrapped space of "bmap".
 * Since this expression does not depend on the original output dimensions,
 * these can be removed, resulting in an expression in terms
 * of the input dimensions.
 * If "bmap" is actually a set, then the resulting expression has no domain.
 *
 * First obtain the expressions
 *
 *  -t f(x)/m
 *  g(x)
 *
 * multiply the first with -t, take the floor and multiply with -t again,
 * to obtain
 *
 *  -t f(x)//m
 *
 * Add t (n - 1) and subtract g(x) to obtain
 *
 *  t (n - 1) - t f(x)//m - g(x)
 *
 * Finally, compute the modulo with respect to m and add g(x) back.
 */
static __isl_give isl_aff *construct_mod_ineq(__isl_keep isl_basic_map *bmap,
  int pos, int div, int lower, int t, isl_int n)
{
  isl_ctx *ctx;
  isl_basic_set *bset;
  isl_aff *f, *g;
  isl_val *v;
  isl_bool is_set;
 
  is_set = isl_basic_map_is_set(bmap);
  if (is_set < 0)
    return NULL;
  ctx = isl_basic_map_get_ctx(bmap);
 
  bset = wrap_for_plug_in(isl_basic_map_copy(bmap), is_set);
  f = extract_div_expr_aff(bset, div, pos);
  g = extract_lower_bound_aff(bset, lower, pos);
  isl_basic_set_free(bset);
 
  if (t > 0)
    isl_aff_neg(f);
  f = isl_aff_floor(f);
  if (t > 0)
    isl_aff_neg(f);
 
  v = isl_val_int_from_isl_int(ctx, n);
  v = isl_val_sub_ui(v, 1);
  if (t < 0)
    v = isl_val_neg(v);
  f = isl_aff_add_constant_val(f, v);
 
  f = isl_aff_sub(f, isl_aff_copy(g));
  v = isl_val_int_from_isl_int(ctx, n);
  f = isl_aff_mod_val(f, v);
  f = isl_aff_add(f, g);
 
  f = unwrap_plug_in(f, is_set);
 
  return f;
}
 
/* Given that inequality constraint "ineq" of "bmap" is of the form
 *
 *  f(x) + t m i - m n e + c >= 0
 *
 * with integer division "e" of the form
 *
 *  e = (f(x) + t m i)//(m n)
 *
 * f(x) an expression in the parameters and input dimensions and
 * t is +1 or -1,
 * check whether c <= -(n - 1) m and then look for
 * a pair of inequality constraints
 *
 *  -g(x) + i >= 0
 *   g(x) - i + d >= 0
 *
 * where g(x) is an expression in the parameters and input dimensions and
 * d < n.
 * If successful, return the expression
 *
 *  (t (n - 1) - t f(x)//m - g(x)) mod n + g(x)
 *
 * "v_out" is the position of the output dimensions among the variables.
 * "pos" is the position of the output dimension i.
 * "n_ineq" is the number of inequality constraints.
 * "v_div" is the position of the local dimensions among the variables.
 *
 *
 * First extract the constant value "n".
 * If c' is the constant term of f(x), then the constant term
 * of the inequality constraint is c' + c.
 * Check that c' + c <= c' - (n - 1) m.
 * If so, and if the pair of inequality constraints can be found,
 * then extract the expression above.
 */
static __isl_give isl_maybe_isl_aff try_find_output_mod_ineq_at(
  __isl_keep isl_basic_map *bmap, int v_out, int pos,
  int ineq, int n_ineq, int v_div, int e)
{
  isl_int n, t;
  isl_size lower;
  isl_maybe_isl_aff res = { isl_bool_false, NULL };
 
  isl_int_init(n);
  isl_int_init(t);
 
  isl_int_divexact(n, bmap->ineq[ineq][1 + v_div + e],
        bmap->ineq[ineq][1 + v_out + pos]);
  isl_int_abs(n, n);
  isl_int_sub_ui(t, n, 1);
  isl_int_mul(t, t, bmap->ineq[ineq][1 + v_out + pos]);
  isl_int_abs(t, t);
  isl_int_neg(t, t);
  isl_int_add(t, t, bmap->div[e][1]);
  if (isl_int_le(bmap->ineq[ineq][0], t)) {
    lower = find_output_lower_mod_constraint(bmap, pos, n);
    if (lower < n_ineq) {
      int t;
 
      t = isl_int_sgn(bmap->ineq[ineq][1 + v_out + pos]);
      res.valid = isl_bool_true;
      res.value = construct_mod_ineq(bmap, v_out + pos,
              e, lower, t, n);
    }
  }
 
  isl_int_clear(t);
  isl_int_clear(n);
 
  return res;
}
 
/* In the sequence of length "len" starting at "p",
 * is the element at "pos" the only non-zero element?
 */
static int only_non_zero(isl_int *p, unsigned pos, unsigned len)
{
  if (isl_int_is_zero(p[pos]))
    return 0;
  return unique(p, pos, len);
}
 
/* Look for a combination of inequality constraints in "bmap" that ensure
 * that output dimension "pos" is equal to some modulo expression
 * in the parameters and input dimensions and
 * return this expression if found.
 *
 * The constraints are assumed to have been sorted.
 *
 * In particular, look for an integer division of the form
 *
 *  e = (f(x) + t m i)//(m n)
 *
 * with a corresponding inequality constraint
 *
 *  f(x) + t m i - m n e + c >= 0         (*)
 *
 * and a pair of inequality constraints
 *
 *  -g(x) + i >= 0
 *   g(x) - i + d >= 0
 *
 * where f(x) and g(x) are expressions in the parameters and input dimensions,
 * c <= -(n - 1) m
 * t is +1 or -1, and
 * d < n.
 *
 * Note that
 *
 *  e = (f(x) + t m i)//(m n) = (f(x)//m + t i)//n
 *
 * and so
 *
 *  f(x)//m + t i - (n - 1) <= n e <= f(x)//m + t i
 *
 * and in particular
 *
 *  f(x)//m <= - t i + n e + (n - 1)
 *
 * Constraint (*) implies
 *
 *  f(x) >= -t m i + m n e - c >= -t m i + m n e + (n - 1) m
 *
 * and so
 *
 *  f(x)//m >= - t i + n e + (n - 1)
 *
 * Together, this implies
 *
 *  f(x)//m = -t i + n e + (n - 1)
 *  t i = n e + (n - 1) - f(x)//m
 *  i = t n e + t (n - 1) - t f(x)//m
 *  i - g(x) = t n e + t (n - 1) - t f(x)//m - g(x)
 *
 * and so, because 0 <= i - g(x) <= d < n,
 *
 *  i - g(x) = (t (n - 1) - t f(x)//m - g(x)) mod n
 *
 * That is,
 *
 *  i = (t (n - 1) - t f(x)//m - g(x)) mod n + g(x)
 *
 *
 * First look for a suitable inequality constraint for (*),
 * with the corresponding integer division.
 * If any such combination is found, look for an appropriate g(x) and
 * construct the corresponding expression in try_find_output_mod_ineq_at.
 */
static __isl_give isl_maybe_isl_aff isl_basic_map_try_find_output_mod_ineq(
  __isl_keep isl_basic_map *bmap, int pos)
{
  int i;
  isl_size n_ineq;
  isl_size v_out, n_out;
  isl_size v_div, n_div;
  isl_maybe_isl_aff no = { isl_bool_false, NULL };
  isl_maybe_isl_aff error = { isl_bool_error, NULL };
 
  n_ineq = isl_basic_map_n_inequality(bmap);
  v_out = isl_basic_map_var_offset(bmap, isl_dim_out);
  n_out = isl_basic_map_dim(bmap, isl_dim_out);
  v_div = isl_basic_map_var_offset(bmap, isl_dim_div);
  n_div = isl_basic_map_dim(bmap, isl_dim_div);
  if (n_ineq < 0 || v_out < 0 || n_out < 0 || v_div < 0 || n_div < 0)
    return error;
  if (n_div < 1 || n_ineq < 4)
    return no;
 
  for (i = 0; i < n_ineq; ++i) {
    isl_bool unknown;
    int e;
 
    if (!only_non_zero(bmap->ineq[i] + 1 + v_out, pos, n_out))
      continue;
    e = isl_seq_last_non_zero(bmap->ineq[i] + 1 + v_div, n_div);
    if (e == -1)
      continue;
    unknown = isl_basic_map_div_is_marked_unknown(bmap, e);
    if (unknown < 0)
      return error;
    if (unknown)
      continue;
    if (isl_seq_any_non_zero(bmap->ineq[i] + 1 + v_div, e))
      continue;
    if (isl_int_is_pos(bmap->ineq[i][1 + v_div + e]))
      continue;
    if (!isl_int_is_divisible_by(bmap->ineq[i][1 + v_div + e],
              bmap->ineq[i][1 + v_out + pos]))
      continue;
    if (!isl_int_abs_eq(bmap->ineq[i][1 + v_div + e],
        bmap->div[e][0]))
      continue;
    if (!isl_seq_eq(bmap->ineq[i] + 1, bmap->div[e] + 2, v_div + e))
      continue;
    return try_find_output_mod_ineq_at(bmap, v_out, pos, i, n_ineq,
              v_div, e);
  }
 
  return no;
}
 
/* Look for a combination of constraints in "bmap" that ensure
 * that output dimension "pos" is equal to some modulo expression
 * in the parameters and input dimensions and
 * return this expression if found.
 *
 * The constraints are assumed to have been sorted.
 *
 * First look for a pattern involving an equality constraint and
 * then look for a pattern involving only inequality constraints.
 */
__isl_give isl_maybe_isl_aff isl_basic_map_try_find_output_mod(
  __isl_keep isl_basic_map *bmap, int pos)
{
  isl_maybe_isl_aff mod;
 
  mod = isl_basic_map_try_find_output_mod_eq(bmap, pos);
  if (mod.valid < 0 || mod.valid)
    return mod;
  return isl_basic_map_try_find_output_mod_ineq(bmap, pos);
}
 
/* Construct an isl_aff from the given domain local space "ls" and
 * coefficients "v", where the local space may involve
 * local variables without a known expression, as long as these
 * do not have a non-zero coefficient in "v".
 * These need to be pruned away first since an isl_aff cannot
 * reference any local variables without a known expression.
 * For simplicity, remove all local variables that have a zero coefficient and
 * that are not used in other local variables with a non-zero coefficient.
 */
static __isl_give isl_aff *isl_aff_alloc_vec_prune(
  __isl_take isl_local_space *ls, __isl_take isl_vec *v)
{
  int i;
  isl_size n_div, v_div;
 
  n_div = isl_local_space_dim(ls, isl_dim_div);
  v_div = isl_local_space_var_offset(ls, isl_dim_div);
  if (n_div < 0 || v_div < 0 || !v)
    goto error;
  for (i = n_div - 1; i >= 0; --i) {
    isl_bool involves;
 
    if (!isl_int_is_zero(v->el[1 + 1 + v_div + i]))
      continue;
    involves = isl_local_space_involves_dims(ls, isl_dim_div, i, 1);
    if (involves < 0)
      goto error;
    if (involves)
      continue;
    ls = isl_local_space_drop_dims(ls, isl_dim_div, i, 1);
    v = isl_vec_drop_els(v, 1 + 1 + v_div + i, 1);
    if (!v)
      goto error;
  }
 
  return isl_aff_alloc_vec(ls, v);
error:
  isl_local_space_free(ls);
  isl_vec_free(v);
  return NULL;
}
 
/* Look for a pair of constraints in "bmap" that ensure
 * that output dimension "pos" is equal to some integer division expression
 * in the parameters and input dimensions and
 * return this expression if found.
 *
 * In particular, looks for a pair of constraints
 *
 *  e(...) + c1 - m x >= 0    i.e.,   m x <= e(...) + c1
 *
 * and
 *
 *  -e(...) + c2 + m x >= 0   i.e.,   m x >= e(...) - c2
 *
 * where m > 1 and e only depends on parameters and input dimensions,
 * and such that
 *
 *  c1 + c2 < m     i.e.,   -c2 >= c1 - (m - 1)
 *
 * If such a pair of constraints can be found
 * then
 *
 *  x = floor((e(...) + c1) / m)
 *
 * with e(...) an expression that does not involve any other output dimensions.
 *
 * Note that we know that
 *
 *  c1 + c2 >= 1
 *
 * If c1 + c2 were 0, then we would have detected an equality during
 * simplification.  If c1 + c2 were negative, then we would have detected
 * a contradiction.
 *
 * The constraint defining the integer division is guaranteed not to involve
 * any local variables without a known expression, but such local variables
 * may appear in other constraints.  They therefore need to be removed
 * during the construction of the affine expression.
 */
static __isl_give isl_maybe_isl_aff isl_basic_map_try_find_output_div(
  __isl_keep isl_basic_map *bmap, int pos)
{
  isl_size i;
  isl_size n_ineq;
  isl_maybe_isl_aff res = { isl_bool_false, NULL };
  isl_local_space *ls;
  isl_aff *aff;
  isl_vec *v;
  isl_bool is_set;
 
  n_ineq = isl_basic_map_n_inequality(bmap);
  if (n_ineq < 0)
    goto error;
 
  i = isl_basic_map_find_output_upper_div_constraint(bmap, pos);
  if (i < 0)
    goto error;
  if (i >= n_ineq)
    return res;
 
  is_set = isl_basic_map_is_set(bmap);
  if (is_set < 0)
    bmap = isl_basic_map_free(bmap);
 
  ls = isl_basic_map_get_local_space(bmap);
  if (!is_set)
    ls = isl_local_space_wrap(ls);
  v = isl_basic_map_inequality_extract_output_upper_bound(bmap, i, pos);
 
  aff = isl_aff_alloc_vec_prune(ls, v);
  aff = isl_aff_floor(aff);
 
  if (is_set)
    aff = isl_aff_project_domain_on_params(aff);
  else
    aff = isl_aff_domain_factor_domain(aff);
 
  res.valid = isl_bool_true;
  res.value = aff;
  return res;
error:
  res.valid = isl_bool_error;
  return res;
}
 
/* Look for a combination of constraints in "bmap" that ensure
 * that output dimension "pos" is equal to some integer division or
 * modulo expression in the parameters and input dimensions and
 * return this expression if found.
 */
__isl_give isl_maybe_isl_aff isl_basic_map_try_find_output_div_mod(
  __isl_keep isl_basic_map *bmap, int pos)
{
  isl_maybe_isl_aff div;
 
  div = isl_basic_map_try_find_output_div(bmap, pos);
  if (div.valid < 0 || div.valid)
    return div;
  return isl_basic_map_try_find_output_mod(bmap, pos);
}
 
/* Look for a combination of constraints in "bmap" that ensure
 * that any output dimension is equal to some integer division or
 * modulo expression in the parameters and input dimensions and
 * return this expression if found.
 * The position of the output dimension (if any) is returned in "pos".
 */
__isl_give isl_maybe_isl_aff isl_basic_map_try_find_any_output_div_mod(
  __isl_keep isl_basic_map *bmap, int *pos)
{
  isl_size dim;
  isl_maybe_isl_aff res = { isl_bool_false, NULL };
 
  dim = isl_basic_map_dim(bmap, isl_dim_out);
  if (dim < 0)
    goto error;
 
  for (*pos = 0; *pos < dim; ++*pos) {
    res = isl_basic_map_try_find_output_div_mod(bmap, *pos);
    if (res.valid < 0 || res.valid)
      return res;
  }
 
  return res;
error:
  res.valid = isl_bool_error;
  return res;
}
 
/* Return a copy of the equality constraints of "bset" as a matrix.
 */
__isl_give isl_mat *isl_basic_set_extract_equalities(
  __isl_keep isl_basic_set *bset)
{
  isl_ctx *ctx;
  isl_size total;
 
  total = isl_basic_set_dim(bset, isl_dim_all);
  if (total < 0)
    return NULL;
 
  ctx = isl_basic_set_get_ctx(bset);
  return isl_mat_sub_alloc6(ctx, bset->eq, 0, bset->n_eq, 0, 1 + total);
}
 
/* Are the "n" "coefficients" starting at "first" of the integer division
 * expressions at position "pos1" in "bmap1" and "pos2" in "bmap2" equal
 * to each other?
 * The "coefficient" at position 0 is the denominator.
 * The "coefficient" at position 1 is the constant term.
 */
isl_bool isl_basic_map_equal_div_expr_part(__isl_keep isl_basic_map *bmap1,
  int pos1, __isl_keep isl_basic_map *bmap2, int pos2,
  unsigned first, unsigned n)
{
  if (isl_basic_map_check_range(bmap1, isl_dim_div, pos1, 1) < 0)
    return isl_bool_error;
  if (isl_basic_map_check_range(bmap2, isl_dim_div, pos2, 1) < 0)
    return isl_bool_error;
  return isl_seq_eq(bmap1->div[pos1] + first,
        bmap2->div[pos2] + first, n);
}
 
/* Are the integer division expressions at position "pos1" in "bmap1" and
 * "pos2" in "bmap2" equal to each other, except that the constant terms
 * are different?
 */
isl_bool isl_basic_map_equal_div_expr_except_constant(
  __isl_keep isl_basic_map *bmap1, int pos1,
  __isl_keep isl_basic_map *bmap2, int pos2)
{
  isl_bool equal;
  isl_size total, total2;
 
  total = isl_basic_map_dim(bmap1, isl_dim_all);
  total2 = isl_basic_map_dim(bmap2, isl_dim_all);
  if (total < 0 || total2 < 0)
    return isl_bool_error;
  if (total != total2)
    isl_die(isl_basic_map_get_ctx(bmap1), isl_error_invalid,
      "incomparable div expressions", return isl_bool_error);
  equal = isl_basic_map_equal_div_expr_part(bmap1, pos1, bmap2, pos2,
            0, 1);
  if (equal < 0 || !equal)
    return equal;
  equal = isl_basic_map_equal_div_expr_part(bmap1, pos1, bmap2, pos2,
            1, 1);
  if (equal < 0 || equal)
    return isl_bool_not(equal);
  return isl_basic_map_equal_div_expr_part(bmap1, pos1, bmap2, pos2,
            2, total);
}
 
/* Replace the numerator of the constant term of the integer division
 * expression at position "div" in "bmap" by "value".
 * The caller guarantees that this does not change the meaning
 * of the input.
 */
__isl_give isl_basic_map *isl_basic_map_set_div_expr_constant_num_si_inplace(
  __isl_take isl_basic_map *bmap, int div, int value)
{
  if (isl_basic_map_check_range(bmap, isl_dim_div, div, 1) < 0)
    return isl_basic_map_free(bmap);
 
  isl_int_set_si(bmap->div[div][1], value);
 
  return bmap;
}
 
/* Is the point "inner" internal to inequality constraint "ineq"
 * of "bset"?
 * The point is considered to be internal to the inequality constraint,
 * if it strictly lies on the positive side of the inequality constraint,
 * or if it lies on the constraint and the constraint is lexico-positive.
 */
static isl_bool is_internal(__isl_keep isl_vec *inner,
  __isl_keep isl_basic_set *bset, int ineq)
{
  isl_ctx *ctx;
  int pos;
  isl_size total;
 
  if (!inner || !bset)
    return isl_bool_error;
 
  ctx = isl_basic_set_get_ctx(bset);
  isl_seq_inner_product(inner->el, bset->ineq[ineq], inner->size,
        &ctx->normalize_gcd);
  if (!isl_int_is_zero(ctx->normalize_gcd))
    return isl_int_is_nonneg(ctx->normalize_gcd);
 
  total = isl_basic_set_dim(bset, isl_dim_all);
  if (total < 0)
    return isl_bool_error;
  pos = isl_seq_first_non_zero(bset->ineq[ineq] + 1, total);
  return isl_int_is_pos(bset->ineq[ineq][1 + pos]);
}
 
/* Tighten the inequality constraints of "bset" that are outward with respect
 * to the point "vec".
 * That is, tighten the constraints that are not satisfied by "vec".
 *
 * "vec" is a point internal to some superset S of "bset" that is used
 * to make the subsets of S disjoint, by tightening one half of the constraints
 * that separate two subsets.  In particular, the constraints of S
 * are all satisfied by "vec" and should not be tightened.
 * Of the internal constraints, those that have "vec" on the outside
 * are tightened.  The shared facet is included in the adjacent subset
 * with the opposite constraint.
 * For constraints that saturate "vec", this criterion cannot be used
 * to determine which of the two sides should be tightened.
 * Instead, the sign of the first non-zero coefficient is used
 * to make this choice.  Note that this second criterion is never used
 * on the constraints of S since "vec" is interior to "S".
 */
__isl_give isl_basic_set *isl_basic_set_tighten_outward(
  __isl_take isl_basic_set *bset, __isl_keep isl_vec *vec)
{
  int j;
 
  bset = isl_basic_set_cow(bset);
  if (!bset)
    return NULL;
  for (j = 0; j < bset->n_ineq; ++j) {
    isl_bool internal;
 
    internal = is_internal(vec, bset, j);
    if (internal < 0)
      return isl_basic_set_free(bset);
    if (internal)
      continue;
    isl_int_sub_ui(bset->ineq[j][0], bset->ineq[j][0], 1);
  }
 
  return bset;
}
 
/* Replace the variables x of type "type" starting at "first" in "bmap"
 * by x' with x = M x' with M the matrix trans.
 * That is, replace the corresponding coefficients c by c M.
 *
 * The transformation matrix should be a square matrix.
 */
__isl_give isl_basic_map *isl_basic_map_transform_dims(
  __isl_take isl_basic_map *bmap, enum isl_dim_type type, unsigned first,
  __isl_take isl_mat *trans)
{
  unsigned pos;
 
  bmap = isl_basic_map_cow(bmap);
  if (!bmap || !trans)
    goto error;
 
  if (trans->n_row != trans->n_col)
    isl_die(trans->ctx, isl_error_invalid,
      "expecting square transformation matrix", goto error);
  if (isl_basic_map_check_range(bmap, type, first, trans->n_row) < 0)
    goto error;
 
  pos = isl_basic_map_offset(bmap, type) + first;
 
  if (isl_mat_sub_transform(bmap->eq, bmap->n_eq, pos,
      isl_mat_copy(trans)) < 0)
    goto error;
  if (isl_mat_sub_transform(bmap->ineq, bmap->n_ineq, pos,
          isl_mat_copy(trans)) < 0)
    goto error;
  if (isl_mat_sub_transform(bmap->div, bmap->n_div, 1 + pos,
          isl_mat_copy(trans)) < 0)
    goto error;
 
  ISL_F_CLR(bmap, ISL_BASIC_MAP_SORTED);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED_DIVS);
  ISL_F_CLR(bmap, ISL_BASIC_MAP_REDUCED_COEFFICIENTS);
 
  isl_mat_free(trans);
  return bmap;
error:
  isl_mat_free(trans);
  isl_basic_map_free(bmap);
  return NULL;
}
 
/* Replace the variables x of type "type" starting at "first" in "bset"
 * by x' with x = M x' with M the matrix trans.
 * That is, replace the corresponding coefficients c by c M.
 *
 * The transformation matrix should be a square matrix.
 */
__isl_give isl_basic_set *isl_basic_set_transform_dims(
  __isl_take isl_basic_set *bset, enum isl_dim_type type, unsigned first,
  __isl_take isl_mat *trans)
{
  return isl_basic_map_transform_dims(bset, type, first, trans);
}