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#include "isl_ctx.h"
#include "isl_lp.h"
#include "isl_lp_piplib.h"
#include "isl_seq.h"
#include "isl_tab.h"
#include "isl_map_private.h"
enum isl_lp_result isl_tab_solve_lp(struct isl_basic_map *bmap, int maximize,
isl_int *f, isl_int denom, isl_int *opt,
isl_int *opt_denom,
struct isl_vec **sol)
{
struct isl_tab *tab;
enum isl_lp_result res;
unsigned dim = isl_basic_map_total_dim(bmap);
if (maximize)
isl_seq_neg(f, f, 1 + dim);
bmap = isl_basic_map_gauss(bmap, NULL);
tab = isl_tab_from_basic_map(bmap);
res = isl_tab_min(tab, f, bmap->ctx->one, opt, opt_denom, 0);
if (res == isl_lp_ok && sol) {
*sol = isl_tab_get_sample_value(tab);
if (!*sol)
res = isl_lp_error;
}
isl_tab_free(tab);
if (maximize)
isl_seq_neg(f, f, 1 + dim);
return res;
}
/* Given a basic map "bmap" and an affine combination of the variables "f"
* with denominator "denom", set *opt/*opt_denom to the minimal
* (or maximal if "maximize" is true) value attained by f/d over "bmap",
* assuming the basic map is not empty and the expression cannot attain
* arbitrarily small (or large) values.
* If opt_denom is NULL, then *opt is rounded up (or down)
* to the nearest integer.
* The return value reflects the nature of the result (empty, unbounded,
* minmimal or maximal value returned in *opt).
*/
enum isl_lp_result isl_basic_map_solve_lp(struct isl_basic_map *bmap, int max,
isl_int *f, isl_int d, isl_int *opt,
isl_int *opt_denom,
struct isl_vec **sol)
{
if (sol)
*sol = NULL;
if (!bmap)
return isl_lp_error;
switch (bmap->ctx->lp_solver) {
case ISL_LP_PIP:
return isl_pip_solve_lp(bmap, max, f, d, opt, opt_denom, sol);
case ISL_LP_TAB:
return isl_tab_solve_lp(bmap, max, f, d, opt, opt_denom, sol);
default:
return isl_lp_error;
}
}
enum isl_lp_result isl_basic_set_solve_lp(struct isl_basic_set *bset, int max,
isl_int *f, isl_int d, isl_int *opt,
isl_int *opt_denom,
struct isl_vec **sol)
{
return isl_basic_map_solve_lp((struct isl_basic_map *)bset, max,
f, d, opt, opt_denom, sol);
}
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