llvm/polly/lib/External/isl/isl_ilp.c

/*
 * Copyright 2008-2009 Katholieke Universiteit Leuven
 *
 * 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
 */

#include <isl_ctx_private.h>
#include <isl_map_private.h>
#include <isl/ilp.h>
#include <isl/union_set.h>
#include "isl_sample.h"
#include <isl_seq.h>
#include "isl_equalities.h"
#include <isl_aff_private.h>
#include <isl_local_space_private.h>
#include <isl_mat_private.h>
#include <isl_val_private.h>
#include <isl_vec_private.h>
#include <isl_lp_private.h>
#include <isl_ilp_private.h>

/* Given a basic set "bset", construct a basic set U such that for
 * each element x in U, the whole unit box positioned at x is inside
 * the given basic set.
 * Note that U may not contain all points that satisfy this property.
 *
 * We simply add the sum of all negative coefficients to the constant
 * term.  This ensures that if x satisfies the resulting constraints,
 * then x plus any sum of unit vectors satisfies the original constraints.
 */
static __isl_give isl_basic_set *unit_box_base_points(
	__isl_take isl_basic_set *bset)
{}

/* Find an integer point in "bset", preferably one that is
 * close to minimizing "f".
 *
 * We first check if we can easily put unit boxes inside bset.
 * If so, we take the best base point of any of the unit boxes we can find
 * and round it up to the nearest integer.
 * If not, we simply pick any integer point in "bset".
 */
static __isl_give isl_vec *initial_solution(__isl_keep isl_basic_set *bset,
	isl_int *f)
{}

/* Restrict "bset" to those points with values for f in the interval [l, u].
 */
static __isl_give isl_basic_set *add_bounds(__isl_take isl_basic_set *bset,
	isl_int *f, isl_int l, isl_int u)
{}

/* Find an integer point in "bset" that minimizes f (in any) such that
 * the value of f lies inside the interval [l, u].
 * Return this integer point if it can be found.
 * Otherwise, return sol.
 *
 * We perform a number of steps until l > u.
 * In each step, we look for an integer point with value in either
 * the whole interval [l, u] or half of the interval [l, l+floor(u-l-1/2)].
 * The choice depends on whether we have found an integer point in the
 * previous step.  If so, we look for the next point in half of the remaining
 * interval.
 * If we find a point, the current solution is updated and u is set
 * to its value minus 1.
 * If no point can be found, we update l to the upper bound of the interval
 * we checked (u or l+floor(u-l-1/2)) plus 1.
 */
static __isl_give isl_vec *solve_ilp_search(__isl_keep isl_basic_set *bset,
	isl_int *f, isl_int *opt, __isl_take isl_vec *sol, isl_int l, isl_int u)
{}

/* Find an integer point in "bset" that minimizes f (if any).
 * If sol_p is not NULL then the integer point is returned in *sol_p.
 * The optimal value of f is returned in *opt.
 *
 * The algorithm maintains a currently best solution and an interval [l, u]
 * of values of f for which integer solutions could potentially still be found.
 * The initial value of the best solution so far is any solution.
 * The initial value of l is minimal value of f over the rationals
 * (rounded up to the nearest integer).
 * The initial value of u is the value of f at the initial solution minus 1.
 *
 * We then call solve_ilp_search to perform a binary search on the interval.
 */
static enum isl_lp_result solve_ilp(__isl_keep isl_basic_set *bset,
	isl_int *f, isl_int *opt, __isl_give isl_vec **sol_p)
{}

static enum isl_lp_result solve_ilp_with_eq(__isl_keep isl_basic_set *bset,
	int max, isl_int *f, isl_int *opt, __isl_give isl_vec **sol_p)
{}

/* Find an integer point in "bset" that minimizes (or maximizes if max is set)
 * f (if any).
 * If sol_p is not NULL then the integer point is returned in *sol_p.
 * The optimal value of f is returned in *opt.
 *
 * If there is any equality among the points in "bset", then we first
 * project it out.  Otherwise, we continue with solve_ilp above.
 */
enum isl_lp_result isl_basic_set_solve_ilp(__isl_keep isl_basic_set *bset,
	int max, isl_int *f, isl_int *opt, __isl_give isl_vec **sol_p)
{}

static enum isl_lp_result basic_set_opt(__isl_keep isl_basic_set *bset, int max,
	__isl_keep isl_aff *obj, isl_int *opt)
{}

enum isl_lp_result isl_basic_set_opt(__isl_keep isl_basic_set *bset, int max,
	__isl_keep isl_aff *obj, isl_int *opt)
{}

/* Compute the minimum (maximum if max is set) of the integer affine
 * expression obj over the points in set and put the result in *opt.
 *
 * The parameters are assumed to have been aligned.
 */
static enum isl_lp_result isl_set_opt_aligned(__isl_keep isl_set *set, int max,
	__isl_keep isl_aff *obj, isl_int *opt)
{}

/* Compute the minimum (maximum if max is set) of the integer affine
 * expression obj over the points in set and put the result in *opt.
 */
enum isl_lp_result isl_set_opt(__isl_keep isl_set *set, int max,
	__isl_keep isl_aff *obj, isl_int *opt)
{}

/* Convert the result of a function that returns an isl_lp_result
 * to an isl_val.  The numerator of "v" is set to the optimal value
 * if lp_res is isl_lp_ok.  "max" is set if a maximum was computed.
 *
 * Return "v" with denominator set to 1 if lp_res is isl_lp_ok.
 * Return NULL on error.
 * Return a NaN if lp_res is isl_lp_empty.
 * Return infinity or negative infinity if lp_res is isl_lp_unbounded,
 * depending on "max".
 */
static __isl_give isl_val *convert_lp_result(enum isl_lp_result lp_res,
	__isl_take isl_val *v, int max)
{}

/* Return the minimum (maximum if max is set) of the integer affine
 * expression "obj" over the points in "bset".
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if "bset" is empty.
 *
 * Call isl_basic_set_opt and translate the results.
 */
__isl_give isl_val *isl_basic_set_opt_val(__isl_keep isl_basic_set *bset,
	int max, __isl_keep isl_aff *obj)
{}

/* Return the maximum of the integer affine
 * expression "obj" over the points in "bset".
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if "bset" is empty.
 */
__isl_give isl_val *isl_basic_set_max_val(__isl_keep isl_basic_set *bset,
	__isl_keep isl_aff *obj)
{}

/* Return the minimum (maximum if max is set) of the integer affine
 * expression "obj" over the points in "set".
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if "set" is empty.
 *
 * Call isl_set_opt and translate the results.
 */
__isl_give isl_val *isl_set_opt_val(__isl_keep isl_set *set, int max,
	__isl_keep isl_aff *obj)
{}

/* Return the minimum of the integer affine
 * expression "obj" over the points in "set".
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if "set" is empty.
 */
__isl_give isl_val *isl_set_min_val(__isl_keep isl_set *set,
	__isl_keep isl_aff *obj)
{}

/* Return the maximum of the integer affine
 * expression "obj" over the points in "set".
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if "set" is empty.
 */
__isl_give isl_val *isl_set_max_val(__isl_keep isl_set *set,
	__isl_keep isl_aff *obj)
{}

/* Return the optimum (min or max depending on "max") of "v1" and "v2",
 * where either may be NaN, signifying an uninitialized value.
 * That is, if either is NaN, then return the other one.
 */
static __isl_give isl_val *val_opt(__isl_take isl_val *v1,
	__isl_take isl_val *v2, int max)
{}

/* Internal data structure for isl_pw_aff_opt_val.
 *
 * "max" is set if the maximum should be computed.
 * "res" contains the current optimum and is initialized to NaN.
 */
struct isl_pw_aff_opt_data {};

/* Update the optimum in data->res with respect to the affine function
 * "aff" defined over "set".
 */
static isl_stat piece_opt(__isl_take isl_set *set, __isl_take isl_aff *aff,
	void *user)
{}

/* Return the minimum (maximum if "max" is set) of the integer piecewise affine
 * expression "pa" over its definition domain.
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if the domain of "pa" is empty.
 *
 * Initialize the result to NaN and then update it for each of the pieces
 * in "pa".
 */
static __isl_give isl_val *isl_pw_aff_opt_val(__isl_take isl_pw_aff *pa,
	int max)
{}

#undef TYPE
#define TYPE
#include "isl_ilp_opt_fn_val_templ.c"

#undef TYPE
#define TYPE
#include "isl_ilp_opt_multi_val_templ.c"

#undef TYPE
#define TYPE
#include "isl_ilp_opt_multi_val_templ.c"

/* Internal data structure for isl_union_pw_aff_opt_val.
 *
 * "max" is set if the maximum should be computed.
 * "res" contains the current optimum and is initialized to NaN.
 */
struct isl_union_pw_aff_opt_data {};

/* Update the optimum in data->res with the optimum of "pa".
 */
static isl_stat pw_aff_opt(__isl_take isl_pw_aff *pa, void *user)
{}

/* Return the minimum (maximum if "max" is set) of the integer piecewise affine
 * expression "upa" over its definition domain.
 *
 * Return infinity or negative infinity if the optimal value is unbounded and
 * NaN if the domain of the expression is empty.
 *
 * Initialize the result to NaN and then update it
 * for each of the piecewise affine expressions in "upa".
 */
static __isl_give isl_val *isl_union_pw_aff_opt_val(
	__isl_take isl_union_pw_aff *upa, int max)
{}

#undef TYPE
#define TYPE
#include "isl_ilp_opt_fn_val_templ.c"

/* Return a list of minima (maxima if "max" is set)
 * for each of the expressions in "mupa" over their domains.
 *
 * An element in the list is infinity or negative infinity if the optimal
 * value of the corresponding expression is unbounded and
 * NaN if the domain of the expression is empty.
 *
 * Iterate over all the expressions in "mupa" and collect the results.
 */
static __isl_give isl_multi_val *isl_multi_union_pw_aff_opt_multi_val(
	__isl_take isl_multi_union_pw_aff *mupa, int max)
{}

/* Return a list of minima (maxima if "max" is set) over the points in "uset"
 * for each of the expressions in "obj".
 *
 * An element in the list is infinity or negative infinity if the optimal
 * value of the corresponding expression is unbounded and
 * NaN if the intersection of "uset" with the domain of the expression
 * is empty.
 */
static __isl_give isl_multi_val *isl_union_set_opt_multi_union_pw_aff(
	__isl_keep isl_union_set *uset, int max,
	__isl_keep isl_multi_union_pw_aff *obj)
{}

/* Return a list of minima over the points in "uset"
 * for each of the expressions in "obj".
 *
 * An element in the list is infinity or negative infinity if the optimal
 * value of the corresponding expression is unbounded and
 * NaN if the intersection of "uset" with the domain of the expression
 * is empty.
 */
__isl_give isl_multi_val *isl_union_set_min_multi_union_pw_aff(
	__isl_keep isl_union_set *uset, __isl_keep isl_multi_union_pw_aff *obj)
{}

/* Return a list of minima
 * for each of the expressions in "mupa" over their domains.
 *
 * An element in the list is negative infinity if the optimal
 * value of the corresponding expression is unbounded and
 * NaN if the domain of the expression is empty.
 */
__isl_give isl_multi_val *isl_multi_union_pw_aff_min_multi_val(
	__isl_take isl_multi_union_pw_aff *mupa)
{}

/* Return a list of maxima
 * for each of the expressions in "mupa" over their domains.
 *
 * An element in the list is infinity if the optimal
 * value of the corresponding expression is unbounded and
 * NaN if the domain of the expression is empty.
 */
__isl_give isl_multi_val *isl_multi_union_pw_aff_max_multi_val(
	__isl_take isl_multi_union_pw_aff *mupa)
{}

#undef BASE
#define BASE
#include "isl_ilp_opt_val_templ.c"

/* Return the maximal value attained by the given set dimension,
 * independently of the parameter values and of any other dimensions.
 *
 * Return infinity if the optimal value is unbounded and
 * NaN if "bset" is empty.
 */
__isl_give isl_val *isl_basic_set_dim_max_val(__isl_take isl_basic_set *bset,
	int pos)
{}

#undef BASE
#define BASE
#include "isl_ilp_opt_val_templ.c"

/* Return the minimal value attained by the given set dimension,
 * independently of the parameter values and of any other dimensions.
 *
 * Return negative infinity if the optimal value is unbounded and
 * NaN if "set" is empty.
 */
__isl_give isl_val *isl_set_dim_min_val(__isl_take isl_set *set, int pos)
{}

/* Return the maximal value attained by the given set dimension,
 * independently of the parameter values and of any other dimensions.
 *
 * Return infinity if the optimal value is unbounded and
 * NaN if "set" is empty.
 */
__isl_give isl_val *isl_set_dim_max_val(__isl_take isl_set *set, int pos)
{}