+/*
+ * Copyright 2008-2009 Katholieke Universiteit Leuven
+ *
+ * Use of this software is governed by the GNU LGPLv2.1 license
+ *
+ * Written by Sven Verdoolaege, K.U.Leuven, Departement
+ * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
+ */
+
#include "isl_map_private.h"
#include "isl_seq.h"
#include "isl_tab.h"
+#include "isl_sample.h"
/*
* The implementation of parametric integer linear programming in this file
* Taking as initial smaple value x' = 0 corresponds to x = -M,
* which is always smaller than any possible value of x.
*
- * We use the big parameter trick both in the main tableau and
- * the context tableau, each of course having its own big parameter.
+ * The big parameter trick is used in the main tableau and
+ * also in the context tableau if isl_context_lex is used.
+ * In this case, each tableaus has its own big parameter.
* Before doing any real work, we check if all the parameters
* happen to be non-negative. If so, we drop the column corresponding
* to M from the initial context tableau.
+ * If isl_context_gbr is used, then the big parameter trick is only
+ * used in the main tableau.
*/
+struct isl_context;
+struct isl_context_op {
+ /* detect nonnegative parameters in context and mark them in tab */
+ struct isl_tab *(*detect_nonnegative_parameters)(
+ struct isl_context *context, struct isl_tab *tab);
+ /* return temporary reference to basic set representation of context */
+ struct isl_basic_set *(*peek_basic_set)(struct isl_context *context);
+ /* return temporary reference to tableau representation of context */
+ struct isl_tab *(*peek_tab)(struct isl_context *context);
+ /* add equality; check is 1 if eq may not be valid;
+ * update is 1 if we may want to call ineq_sign on context later.
+ */
+ void (*add_eq)(struct isl_context *context, isl_int *eq,
+ int check, int update);
+ /* add inequality; check is 1 if ineq may not be valid;
+ * update is 1 if we may want to call ineq_sign on context later.
+ */
+ void (*add_ineq)(struct isl_context *context, isl_int *ineq,
+ int check, int update);
+ /* check sign of ineq based on previous information.
+ * strict is 1 if saturation should be treated as a positive sign.
+ */
+ enum isl_tab_row_sign (*ineq_sign)(struct isl_context *context,
+ isl_int *ineq, int strict);
+ /* check if inequality maintains feasibility */
+ int (*test_ineq)(struct isl_context *context, isl_int *ineq);
+ /* return index of a div that corresponds to "div" */
+ int (*get_div)(struct isl_context *context, struct isl_tab *tab,
+ struct isl_vec *div);
+ /* add div "div" to context and return non-negativity */
+ int (*add_div)(struct isl_context *context, struct isl_vec *div);
+ int (*detect_equalities)(struct isl_context *context,
+ struct isl_tab *tab);
+ /* return row index of "best" split */
+ int (*best_split)(struct isl_context *context, struct isl_tab *tab);
+ /* check if context has already been determined to be empty */
+ int (*is_empty)(struct isl_context *context);
+ /* check if context is still usable */
+ int (*is_ok)(struct isl_context *context);
+ /* save a copy/snapshot of context */
+ void *(*save)(struct isl_context *context);
+ /* restore saved context */
+ void (*restore)(struct isl_context *context, void *);
+ /* invalidate context */
+ void (*invalidate)(struct isl_context *context);
+ /* free context */
+ void (*free)(struct isl_context *context);
+};
+
+struct isl_context {
+ struct isl_context_op *op;
+};
+
+struct isl_context_lex {
+ struct isl_context context;
+ struct isl_tab *tab;
+};
+
+struct isl_partial_sol {
+ int level;
+ struct isl_basic_set *dom;
+ struct isl_mat *M;
+
+ struct isl_partial_sol *next;
+};
+
+struct isl_sol;
+struct isl_sol_callback {
+ struct isl_tab_callback callback;
+ struct isl_sol *sol;
+};
+
/* isl_sol is an interface for constructing a solution to
* a parametric integer linear programming problem.
* Every time the algorithm reaches a state where a solution
* the solution.
*/
struct isl_sol {
- struct isl_tab *context_tab;
- struct isl_sol *(*add)(struct isl_sol *sol, struct isl_tab *tab);
+ int error;
+ int rational;
+ int level;
+ int max;
+ int n_out;
+ struct isl_context *context;
+ struct isl_partial_sol *partial;
+ void (*add)(struct isl_sol *sol,
+ struct isl_basic_set *dom, struct isl_mat *M);
+ void (*add_empty)(struct isl_sol *sol, struct isl_basic_set *bset);
void (*free)(struct isl_sol *sol);
+ struct isl_sol_callback dec_level;
};
static void sol_free(struct isl_sol *sol)
{
+ struct isl_partial_sol *partial, *next;
if (!sol)
return;
+ for (partial = sol->partial; partial; partial = next) {
+ next = partial->next;
+ isl_basic_set_free(partial->dom);
+ isl_mat_free(partial->M);
+ free(partial);
+ }
sol->free(sol);
}
-struct isl_sol_map {
- struct isl_sol sol;
- struct isl_map *map;
- struct isl_set *empty;
- int max;
-};
-
-static void sol_map_free(struct isl_sol_map *sol_map)
+/* Push a partial solution represented by a domain and mapping M
+ * onto the stack of partial solutions.
+ */
+static void sol_push_sol(struct isl_sol *sol,
+ struct isl_basic_set *dom, struct isl_mat *M)
{
- isl_tab_free(sol_map->sol.context_tab);
- isl_map_free(sol_map->map);
- isl_set_free(sol_map->empty);
- free(sol_map);
+ struct isl_partial_sol *partial;
+
+ if (sol->error || !dom)
+ goto error;
+
+ partial = isl_alloc_type(dom->ctx, struct isl_partial_sol);
+ if (!partial)
+ goto error;
+
+ partial->level = sol->level;
+ partial->dom = dom;
+ partial->M = M;
+ partial->next = sol->partial;
+
+ sol->partial = partial;
+
+ return;
+error:
+ isl_basic_set_free(dom);
+ sol->error = 1;
}
-static void sol_map_free_wrap(struct isl_sol *sol)
+/* Pop one partial solution from the partial solution stack and
+ * pass it on to sol->add or sol->add_empty.
+ */
+static void sol_pop_one(struct isl_sol *sol)
{
- sol_map_free((struct isl_sol_map *)sol);
+ struct isl_partial_sol *partial;
+
+ partial = sol->partial;
+ sol->partial = partial->next;
+
+ if (partial->M)
+ sol->add(sol, partial->dom, partial->M);
+ else
+ sol->add_empty(sol, partial->dom);
+ free(partial);
}
-static struct isl_sol_map *add_empty(struct isl_sol_map *sol)
+/* Return a fresh copy of the domain represented by the context tableau.
+ */
+static struct isl_basic_set *sol_domain(struct isl_sol *sol)
{
struct isl_basic_set *bset;
- if (!sol->empty)
- return sol;
- sol->empty = isl_set_grow(sol->empty, 1);
- bset = isl_basic_set_copy(sol->sol.context_tab->bset);
- bset = isl_basic_set_simplify(bset);
- bset = isl_basic_set_finalize(bset);
- sol->empty = isl_set_add(sol->empty, bset);
- if (!sol->empty)
- goto error;
- return sol;
-error:
- sol_map_free(sol);
- return NULL;
+ if (sol->error)
+ return NULL;
+
+ bset = isl_basic_set_dup(sol->context->op->peek_basic_set(sol->context));
+ bset = isl_basic_set_update_from_tab(bset,
+ sol->context->op->peek_tab(sol->context));
+
+ return bset;
+}
+
+/* Check whether two partial solutions have the same mapping, where n_div
+ * is the number of divs that the two partial solutions have in common.
+ */
+static int same_solution(struct isl_partial_sol *s1, struct isl_partial_sol *s2,
+ unsigned n_div)
+{
+ int i;
+ unsigned dim;
+
+ if (!s1->M != !s2->M)
+ return 0;
+ if (!s1->M)
+ return 1;
+
+ dim = isl_basic_set_total_dim(s1->dom) - s1->dom->n_div;
+
+ for (i = 0; i < s1->M->n_row; ++i) {
+ if (isl_seq_first_non_zero(s1->M->row[i]+1+dim+n_div,
+ s1->M->n_col-1-dim-n_div) != -1)
+ return 0;
+ if (isl_seq_first_non_zero(s2->M->row[i]+1+dim+n_div,
+ s2->M->n_col-1-dim-n_div) != -1)
+ return 0;
+ if (!isl_seq_eq(s1->M->row[i], s2->M->row[i], 1+dim+n_div))
+ return 0;
+ }
+ return 1;
+}
+
+/* Pop all solutions from the partial solution stack that were pushed onto
+ * the stack at levels that are deeper than the current level.
+ * If the two topmost elements on the stack have the same level
+ * and represent the same solution, then their domains are combined.
+ * This combined domain is the same as the current context domain
+ * as sol_pop is called each time we move back to a higher level.
+ */
+static void sol_pop(struct isl_sol *sol)
+{
+ struct isl_partial_sol *partial;
+ unsigned n_div;
+
+ if (sol->error)
+ return;
+
+ if (sol->level == 0) {
+ for (partial = sol->partial; partial; partial = sol->partial)
+ sol_pop_one(sol);
+ return;
+ }
+
+ partial = sol->partial;
+ if (!partial)
+ return;
+
+ if (partial->level <= sol->level)
+ return;
+
+ if (partial->next && partial->next->level == partial->level) {
+ n_div = isl_basic_set_dim(
+ sol->context->op->peek_basic_set(sol->context),
+ isl_dim_div);
+
+ if (!same_solution(partial, partial->next, n_div)) {
+ sol_pop_one(sol);
+ sol_pop_one(sol);
+ } else {
+ struct isl_basic_set *bset;
+
+ bset = sol_domain(sol);
+
+ isl_basic_set_free(partial->next->dom);
+ partial->next->dom = bset;
+ partial->next->level = sol->level;
+
+ sol->partial = partial->next;
+ isl_basic_set_free(partial->dom);
+ isl_mat_free(partial->M);
+ free(partial);
+ }
+ } else
+ sol_pop_one(sol);
+}
+
+static void sol_dec_level(struct isl_sol *sol)
+{
+ if (sol->error)
+ return;
+
+ sol->level--;
+
+ sol_pop(sol);
+}
+
+static int sol_dec_level_wrap(struct isl_tab_callback *cb)
+{
+ struct isl_sol_callback *callback = (struct isl_sol_callback *)cb;
+
+ sol_dec_level(callback->sol);
+
+ return callback->sol->error ? -1 : 0;
+}
+
+/* Move down to next level and push callback onto context tableau
+ * to decrease the level again when it gets rolled back across
+ * the current state. That is, dec_level will be called with
+ * the context tableau in the same state as it is when inc_level
+ * is called.
+ */
+static void sol_inc_level(struct isl_sol *sol)
+{
+ struct isl_tab *tab;
+
+ if (sol->error)
+ return;
+
+ sol->level++;
+ tab = sol->context->op->peek_tab(sol->context);
+ if (isl_tab_push_callback(tab, &sol->dec_level.callback) < 0)
+ sol->error = 1;
+}
+
+static void scale_rows(struct isl_mat *mat, isl_int m, int n_row)
+{
+ int i;
+
+ if (isl_int_is_one(m))
+ return;
+
+ for (i = 0; i < n_row; ++i)
+ isl_seq_scale(mat->row[i], mat->row[i], m, mat->n_col);
}
/* Add the solution identified by the tableau and the context tableau.
* dimensions in the input map
* tab->n_div is equal to the number of divs in the context
*
- * If there is no solution, then the basic set corresponding to the
- * context tableau is added to the set "empty".
+ * If there is no solution, then call add_empty with a basic set
+ * that corresponds to the context tableau. (If add_empty is NULL,
+ * then do nothing).
*
- * Otherwise, a basic map is constructed with the same parameters
- * and divs as the context, the dimensions of the context as input
- * dimensions and a number of output dimensions that is equal to
- * the number of output dimensions in the input map.
+ * If there is a solution, then first construct a matrix that maps
+ * all dimensions of the context to the output variables, i.e.,
+ * the output dimensions in the input map.
* The divs in the input map (if any) that do not correspond to any
* div in the context do not appear in the solution.
* The algorithm will make sure that they have an integer value,
* but these values themselves are of no interest.
+ * We have to be careful not to drop or rearrange any divs in the
+ * context because that would change the meaning of the matrix.
*
- * The constraints and divs of the context are simply copied
- * fron context_tab->bset.
* To extract the value of the output variables, it should be noted
- * that we always use a big parameter M and so the variable stored
- * in the tableau is not an output variable x itself, but
+ * that we always use a big parameter M in the main tableau and so
+ * the variable stored in this tableau is not an output variable x itself, but
* x' = M + x (in case of minimization)
* or
* x' = M - x (in case of maximization)
* are bounded, so this cannot occur.
* Similarly, when x' appears in a row, then the coefficient of M in that
* row is necessarily 1.
- * If the row represents
+ * If the row in the tableau represents
* d x' = c + d M + e(y)
- * then, in case of minimization, an equality
- * c + e(y) - d x' = 0
- * is added, and in case of maximization,
- * c + e(y) + d x' = 0
+ * then, in case of minimization, the corresponding row in the matrix
+ * will be
+ * a c + a e(y)
+ * with a d = m, the (updated) common denominator of the matrix.
+ * In case of maximization, the row will be
+ * -a c - a e(y)
*/
-static struct isl_sol_map *sol_map_add(struct isl_sol_map *sol,
- struct isl_tab *tab)
+static void sol_add(struct isl_sol *sol, struct isl_tab *tab)
+{
+ struct isl_basic_set *bset = NULL;
+ struct isl_mat *mat = NULL;
+ unsigned off;
+ int row, i;
+ isl_int m;
+
+ if (sol->error || !tab)
+ goto error;
+
+ if (tab->empty && !sol->add_empty)
+ return;
+
+ bset = sol_domain(sol);
+
+ if (tab->empty) {
+ sol_push_sol(sol, bset, NULL);
+ return;
+ }
+
+ off = 2 + tab->M;
+
+ mat = isl_mat_alloc(tab->mat->ctx, 1 + sol->n_out,
+ 1 + tab->n_param + tab->n_div);
+ if (!mat)
+ goto error;
+
+ isl_int_init(m);
+
+ isl_seq_clr(mat->row[0] + 1, mat->n_col - 1);
+ isl_int_set_si(mat->row[0][0], 1);
+ for (row = 0; row < sol->n_out; ++row) {
+ int i = tab->n_param + row;
+ int r, j;
+
+ isl_seq_clr(mat->row[1 + row], mat->n_col);
+ if (!tab->var[i].is_row) {
+ /* no unbounded */
+ isl_assert(mat->ctx, !tab->M, goto error2);
+ continue;
+ }
+
+ r = tab->var[i].index;
+ /* no unbounded */
+ if (tab->M)
+ isl_assert(mat->ctx, isl_int_eq(tab->mat->row[r][2],
+ tab->mat->row[r][0]),
+ goto error2);
+ isl_int_gcd(m, mat->row[0][0], tab->mat->row[r][0]);
+ isl_int_divexact(m, tab->mat->row[r][0], m);
+ scale_rows(mat, m, 1 + row);
+ isl_int_divexact(m, mat->row[0][0], tab->mat->row[r][0]);
+ isl_int_mul(mat->row[1 + row][0], m, tab->mat->row[r][1]);
+ for (j = 0; j < tab->n_param; ++j) {
+ int col;
+ if (tab->var[j].is_row)
+ continue;
+ col = tab->var[j].index;
+ isl_int_mul(mat->row[1 + row][1 + j], m,
+ tab->mat->row[r][off + col]);
+ }
+ for (j = 0; j < tab->n_div; ++j) {
+ int col;
+ if (tab->var[tab->n_var - tab->n_div+j].is_row)
+ continue;
+ col = tab->var[tab->n_var - tab->n_div+j].index;
+ isl_int_mul(mat->row[1 + row][1 + tab->n_param + j], m,
+ tab->mat->row[r][off + col]);
+ }
+ if (sol->max)
+ isl_seq_neg(mat->row[1 + row], mat->row[1 + row],
+ mat->n_col);
+ }
+
+ isl_int_clear(m);
+
+ sol_push_sol(sol, bset, mat);
+ return;
+error2:
+ isl_int_clear(m);
+error:
+ isl_basic_set_free(bset);
+ isl_mat_free(mat);
+ sol_free(sol);
+}
+
+struct isl_sol_map {
+ struct isl_sol sol;
+ struct isl_map *map;
+ struct isl_set *empty;
+};
+
+static void sol_map_free(struct isl_sol_map *sol_map)
+{
+ if (!sol_map)
+ return;
+ if (sol_map->sol.context)
+ sol_map->sol.context->op->free(sol_map->sol.context);
+ isl_map_free(sol_map->map);
+ isl_set_free(sol_map->empty);
+ free(sol_map);
+}
+
+static void sol_map_free_wrap(struct isl_sol *sol)
+{
+ sol_map_free((struct isl_sol_map *)sol);
+}
+
+/* This function is called for parts of the context where there is
+ * no solution, with "bset" corresponding to the context tableau.
+ * Simply add the basic set to the set "empty".
+ */
+static void sol_map_add_empty(struct isl_sol_map *sol,
+ struct isl_basic_set *bset)
+{
+ if (!bset)
+ goto error;
+ isl_assert(bset->ctx, sol->empty, goto error);
+
+ sol->empty = isl_set_grow(sol->empty, 1);
+ bset = isl_basic_set_simplify(bset);
+ bset = isl_basic_set_finalize(bset);
+ sol->empty = isl_set_add_basic_set(sol->empty, isl_basic_set_copy(bset));
+ if (!sol->empty)
+ goto error;
+ isl_basic_set_free(bset);
+ return;
+error:
+ isl_basic_set_free(bset);
+ sol->sol.error = 1;
+}
+
+static void sol_map_add_empty_wrap(struct isl_sol *sol,
+ struct isl_basic_set *bset)
+{
+ sol_map_add_empty((struct isl_sol_map *)sol, bset);
+}
+
+/* Add bset to sol's empty, but only if we are actually collecting
+ * the empty set.
+ */
+static void sol_map_add_empty_if_needed(struct isl_sol_map *sol,
+ struct isl_basic_set *bset)
+{
+ if (sol->empty)
+ sol_map_add_empty(sol, bset);
+ else
+ isl_basic_set_free(bset);
+}
+
+/* Given a basic map "dom" that represents the context and an affine
+ * matrix "M" that maps the dimensions of the context to the
+ * output variables, construct a basic map with the same parameters
+ * and divs as the context, the dimensions of the context as input
+ * dimensions and a number of output dimensions that is equal to
+ * the number of output dimensions in the input map.
+ *
+ * The constraints and divs of the context are simply copied
+ * from "dom". For each row
+ * x = c + e(y)
+ * an equality
+ * c + e(y) - d x = 0
+ * is added, with d the common denominator of M.
+ */
+static void sol_map_add(struct isl_sol_map *sol,
+ struct isl_basic_set *dom, struct isl_mat *M)
{
int i;
struct isl_basic_map *bmap = NULL;
- struct isl_tab *context_tab;
+ isl_basic_set *context_bset;
unsigned n_eq;
unsigned n_ineq;
unsigned nparam;
unsigned total;
unsigned n_div;
unsigned n_out;
- unsigned off;
- if (!sol || !tab)
+ if (sol->sol.error || !dom || !M)
goto error;
- if (tab->empty)
- return add_empty(sol);
-
- context_tab = sol->sol.context_tab;
- off = 2 + tab->M;
- n_out = isl_map_dim(sol->map, isl_dim_out);
- n_eq = context_tab->bset->n_eq + n_out;
- n_ineq = context_tab->bset->n_ineq;
- nparam = tab->n_param;
+ n_out = sol->sol.n_out;
+ n_eq = dom->n_eq + n_out;
+ n_ineq = dom->n_ineq;
+ n_div = dom->n_div;
+ nparam = isl_basic_set_total_dim(dom) - n_div;
total = isl_map_dim(sol->map, isl_dim_all);
bmap = isl_basic_map_alloc_dim(isl_map_get_dim(sol->map),
- tab->n_div, n_eq, 2 * tab->n_div + n_ineq);
+ n_div, n_eq, 2 * n_div + n_ineq);
if (!bmap)
goto error;
- n_div = tab->n_div;
- if (tab->rational)
+ if (sol->sol.rational)
ISL_F_SET(bmap, ISL_BASIC_MAP_RATIONAL);
- for (i = 0; i < context_tab->bset->n_div; ++i) {
+ for (i = 0; i < dom->n_div; ++i) {
int k = isl_basic_map_alloc_div(bmap);
if (k < 0)
goto error;
- isl_seq_cpy(bmap->div[k],
- context_tab->bset->div[i], 1 + 1 + nparam);
+ isl_seq_cpy(bmap->div[k], dom->div[i], 1 + 1 + nparam);
isl_seq_clr(bmap->div[k] + 1 + 1 + nparam, total - nparam);
isl_seq_cpy(bmap->div[k] + 1 + 1 + total,
- context_tab->bset->div[i] + 1 + 1 + nparam, i);
+ dom->div[i] + 1 + 1 + nparam, i);
}
- for (i = 0; i < context_tab->bset->n_eq; ++i) {
+ for (i = 0; i < dom->n_eq; ++i) {
int k = isl_basic_map_alloc_equality(bmap);
if (k < 0)
goto error;
- isl_seq_cpy(bmap->eq[k], context_tab->bset->eq[i], 1 + nparam);
+ isl_seq_cpy(bmap->eq[k], dom->eq[i], 1 + nparam);
isl_seq_clr(bmap->eq[k] + 1 + nparam, total - nparam);
isl_seq_cpy(bmap->eq[k] + 1 + total,
- context_tab->bset->eq[i] + 1 + nparam, n_div);
+ dom->eq[i] + 1 + nparam, n_div);
}
- for (i = 0; i < context_tab->bset->n_ineq; ++i) {
+ for (i = 0; i < dom->n_ineq; ++i) {
int k = isl_basic_map_alloc_inequality(bmap);
if (k < 0)
goto error;
- isl_seq_cpy(bmap->ineq[k],
- context_tab->bset->ineq[i], 1 + nparam);
+ isl_seq_cpy(bmap->ineq[k], dom->ineq[i], 1 + nparam);
isl_seq_clr(bmap->ineq[k] + 1 + nparam, total - nparam);
isl_seq_cpy(bmap->ineq[k] + 1 + total,
- context_tab->bset->ineq[i] + 1 + nparam, n_div);
+ dom->ineq[i] + 1 + nparam, n_div);
}
- for (i = tab->n_param; i < total; ++i) {
+ for (i = 0; i < M->n_row - 1; ++i) {
int k = isl_basic_map_alloc_equality(bmap);
if (k < 0)
goto error;
- isl_seq_clr(bmap->eq[k] + 1, isl_basic_map_total_dim(bmap));
- if (!tab->var[i].is_row) {
- /* no unbounded */
- isl_assert(bmap->ctx, !tab->M, goto error);
- isl_int_set_si(bmap->eq[k][0], 0);
- if (sol->max)
- isl_int_set_si(bmap->eq[k][1 + i], 1);
- else
- isl_int_set_si(bmap->eq[k][1 + i], -1);
- } else {
- int row, j;
- row = tab->var[i].index;
- /* no unbounded */
- if (tab->M)
- isl_assert(bmap->ctx,
- isl_int_eq(tab->mat->row[row][2],
- tab->mat->row[row][0]),
- goto error);
- isl_int_set(bmap->eq[k][0], tab->mat->row[row][1]);
- for (j = 0; j < tab->n_param; ++j) {
- int col;
- if (tab->var[j].is_row)
- continue;
- col = tab->var[j].index;
- isl_int_set(bmap->eq[k][1 + j],
- tab->mat->row[row][off + col]);
- }
- for (j = 0; j < tab->n_div; ++j) {
- int col;
- if (tab->var[tab->n_var - tab->n_div+j].is_row)
- continue;
- col = tab->var[tab->n_var - tab->n_div+j].index;
- isl_int_set(bmap->eq[k][1 + total + j],
- tab->mat->row[row][off + col]);
- }
- if (sol->max)
- isl_int_set(bmap->eq[k][1 + i],
- tab->mat->row[row][0]);
- else
- isl_int_neg(bmap->eq[k][1 + i],
- tab->mat->row[row][0]);
- }
+ isl_seq_cpy(bmap->eq[k], M->row[1 + i], 1 + nparam);
+ isl_seq_clr(bmap->eq[k] + 1 + nparam, n_out);
+ isl_int_neg(bmap->eq[k][1 + nparam + i], M->row[0][0]);
+ isl_seq_cpy(bmap->eq[k] + 1 + nparam + n_out,
+ M->row[1 + i] + 1 + nparam, n_div);
}
- bmap = isl_basic_map_gauss(bmap, NULL);
- bmap = isl_basic_map_normalize_constraints(bmap);
+ bmap = isl_basic_map_simplify(bmap);
bmap = isl_basic_map_finalize(bmap);
sol->map = isl_map_grow(sol->map, 1);
- sol->map = isl_map_add(sol->map, bmap);
+ sol->map = isl_map_add_basic_map(sol->map, bmap);
if (!sol->map)
goto error;
- return sol;
+ isl_basic_set_free(dom);
+ isl_mat_free(M);
+ return;
error:
+ isl_basic_set_free(dom);
+ isl_mat_free(M);
isl_basic_map_free(bmap);
- sol_free(&sol->sol);
- return NULL;
+ sol->sol.error = 1;
}
-static struct isl_sol *sol_map_add_wrap(struct isl_sol *sol,
- struct isl_tab *tab)
+static void sol_map_add_wrap(struct isl_sol *sol,
+ struct isl_basic_set *dom, struct isl_mat *M)
{
- return (struct isl_sol *)sol_map_add((struct isl_sol_map *)sol, tab);
-}
-
-
-static struct isl_basic_set *isl_basic_set_add_ineq(struct isl_basic_set *bset,
- isl_int *ineq)
-{
- int k;
-
- bset = isl_basic_set_extend_constraints(bset, 0, 1);
- if (!bset)
- return NULL;
- k = isl_basic_set_alloc_inequality(bset);
- if (k < 0)
- goto error;
- isl_seq_cpy(bset->ineq[k], ineq, 1 + isl_basic_set_total_dim(bset));
- return bset;
-error:
- isl_basic_set_free(bset);
- return NULL;
-}
-
-static struct isl_basic_set *isl_basic_set_add_eq(struct isl_basic_set *bset,
- isl_int *eq)
-{
- int k;
-
- bset = isl_basic_set_extend_constraints(bset, 1, 0);
- if (!bset)
- return NULL;
- k = isl_basic_set_alloc_equality(bset);
- if (k < 0)
- goto error;
- isl_seq_cpy(bset->eq[k], eq, 1 + isl_basic_set_total_dim(bset));
- return bset;
-error:
- isl_basic_set_free(bset);
- return NULL;
+ sol_map_add((struct isl_sol_map *)sol, dom, M);
}
unsigned div_pos;
struct isl_vec *ineq;
+ if (!bset)
+ return NULL;
+
total = isl_basic_set_total_dim(bset);
div_pos = 1 + total - bset->n_div + div;
*/
static struct isl_tab *set_row_cst_to_div(struct isl_tab *tab, int row, int div)
{
- int col;
- unsigned off = 2 + tab->M;
-
isl_seq_fdiv_q(tab->mat->row[row] + 1, tab->mat->row[row] + 1,
tab->mat->row[row][0], 1 + tab->M + tab->n_col);
isl_int_set_si(tab->mat->row[row][0], 1);
- isl_assert(tab->mat->ctx,
- !tab->var[tab->n_var - tab->n_div + div].is_row, goto error);
+ if (tab->var[tab->n_var - tab->n_div + div].is_row) {
+ int drow = tab->var[tab->n_var - tab->n_div + div].index;
+
+ isl_assert(tab->mat->ctx,
+ isl_int_is_one(tab->mat->row[drow][0]), goto error);
+ isl_seq_combine(tab->mat->row[row] + 1,
+ tab->mat->ctx->one, tab->mat->row[row] + 1,
+ tab->mat->ctx->one, tab->mat->row[drow] + 1,
+ 1 + tab->M + tab->n_col);
+ } else {
+ int dcol = tab->var[tab->n_var - tab->n_div + div].index;
- col = tab->var[tab->n_var - tab->n_div + div].index;
- isl_int_set_si(tab->mat->row[row][off + col], 1);
+ isl_int_set_si(tab->mat->row[row][2 + tab->M + dcol], 1);
+ }
return tab;
error:
for (row = tab->n_redundant; row < tab->n_row; ++row) {
if (!isl_tab_var_from_row(tab, row)->is_nonneg)
continue;
- if (isl_int_is_neg(tab->mat->row[row][2]))
- return row;
+ if (!isl_int_is_neg(tab->mat->row[row][2]))
+ continue;
+ if (tab->row_sign)
+ tab->row_sign[row] = isl_tab_row_neg;
+ return row;
}
for (row = tab->n_redundant; row < tab->n_row; ++row) {
if (!isl_tab_var_from_row(tab, row)->is_nonneg)
* smallest increment in the sample point. If there is no such column
* then the tableau is infeasible.
*/
+static struct isl_tab *restore_lexmin(struct isl_tab *tab) WARN_UNUSED;
static struct isl_tab *restore_lexmin(struct isl_tab *tab)
{
int row, col;
return tab;
while ((row = first_neg(tab)) != -1) {
col = lexmin_pivot_col(tab, row);
- if (col >= tab->n_col)
- return isl_tab_mark_empty(tab);
+ if (col >= tab->n_col) {
+ if (isl_tab_mark_empty(tab) < 0)
+ goto error;
+ return tab;
+ }
if (col < 0)
goto error;
- isl_tab_pivot(tab, row, col);
+ if (isl_tab_pivot(tab, row, col) < 0)
+ goto error;
}
return tab;
error:
i = last_var_col_or_int_par_col(tab, r);
if (i < 0) {
tab->con[r].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]) < 0)
+ goto error;
isl_seq_neg(eq, eq, 1 + tab->n_var);
r = isl_tab_add_row(tab, eq);
if (r < 0)
goto error;
tab->con[r].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]) < 0)
+ goto error;
} else {
- isl_tab_pivot(tab, r, i);
- isl_tab_kill_col(tab, i);
+ if (isl_tab_pivot(tab, r, i) < 0)
+ goto error;
+ if (isl_tab_kill_col(tab, i) < 0)
+ goto error;
tab->n_eq++;
tab = restore_lexmin(tab);
* In the end we try to use one of the two constraints to eliminate
* a column.
*/
+static struct isl_tab *add_lexmin_eq(struct isl_tab *tab, isl_int *eq) WARN_UNUSED;
static struct isl_tab *add_lexmin_eq(struct isl_tab *tab, isl_int *eq)
{
int r1, r2;
int row;
+ struct isl_tab_undo *snap;
if (!tab)
return NULL;
- if (tab->bset) {
- tab->bset = isl_basic_set_add_eq(tab->bset, eq);
- isl_tab_push(tab, isl_tab_undo_bset_eq);
- if (!tab->bset)
- goto error;
- }
+ snap = isl_tab_snap(tab);
r1 = isl_tab_add_row(tab, eq);
if (r1 < 0)
goto error;
tab->con[r1].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r1]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r1]) < 0)
+ goto error;
row = tab->con[r1].index;
if (is_constant(tab, row)) {
if (!isl_int_is_zero(tab->mat->row[row][1]) ||
- (tab->M && !isl_int_is_zero(tab->mat->row[row][2])))
- return isl_tab_mark_empty(tab);
+ (tab->M && !isl_int_is_zero(tab->mat->row[row][2]))) {
+ if (isl_tab_mark_empty(tab) < 0)
+ goto error;
+ return tab;
+ }
+ if (isl_tab_rollback(tab, snap) < 0)
+ goto error;
return tab;
}
if (r2 < 0)
goto error;
tab->con[r2].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r2]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r2]) < 0)
+ goto error;
tab = restore_lexmin(tab);
if (!tab || tab->empty)
return tab;
- if (!tab->con[r1].is_row)
- isl_tab_kill_col(tab, tab->con[r1].index);
- else if (!tab->con[r2].is_row)
- isl_tab_kill_col(tab, tab->con[r2].index);
- else if (isl_int_is_zero(tab->mat->row[tab->con[r1].index][1])) {
+ if (!tab->con[r1].is_row) {
+ if (isl_tab_kill_col(tab, tab->con[r1].index) < 0)
+ goto error;
+ } else if (!tab->con[r2].is_row) {
+ if (isl_tab_kill_col(tab, tab->con[r2].index) < 0)
+ goto error;
+ } else if (isl_int_is_zero(tab->mat->row[tab->con[r1].index][1])) {
unsigned off = 2 + tab->M;
int i;
int row = tab->con[r1].index;
i = isl_seq_first_non_zero(tab->mat->row[row]+off+tab->n_dead,
tab->n_col - tab->n_dead);
if (i != -1) {
- isl_tab_pivot(tab, row, tab->n_dead + i);
- isl_tab_kill_col(tab, tab->n_dead + i);
+ if (isl_tab_pivot(tab, row, tab->n_dead + i) < 0)
+ goto error;
+ if (isl_tab_kill_col(tab, tab->n_dead + i) < 0)
+ goto error;
}
}
+ if (tab->bmap) {
+ tab->bmap = isl_basic_map_add_ineq(tab->bmap, eq);
+ if (isl_tab_push(tab, isl_tab_undo_bmap_ineq) < 0)
+ goto error;
+ isl_seq_neg(eq, eq, 1 + tab->n_var);
+ tab->bmap = isl_basic_map_add_ineq(tab->bmap, eq);
+ isl_seq_neg(eq, eq, 1 + tab->n_var);
+ if (isl_tab_push(tab, isl_tab_undo_bmap_ineq) < 0)
+ goto error;
+ if (!tab->bmap)
+ goto error;
+ }
+
return tab;
error:
isl_tab_free(tab);
if (!tab)
return NULL;
- if (tab->bset) {
- tab->bset = isl_basic_set_add_ineq(tab->bset, ineq);
- isl_tab_push(tab, isl_tab_undo_bset_ineq);
- if (!tab->bset)
+ if (tab->bmap) {
+ tab->bmap = isl_basic_map_add_ineq(tab->bmap, ineq);
+ if (isl_tab_push(tab, isl_tab_undo_bmap_ineq) < 0)
+ goto error;
+ if (!tab->bmap)
goto error;
}
r = isl_tab_add_row(tab, ineq);
if (r < 0)
goto error;
tab->con[r].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]) < 0)
+ goto error;
if (isl_tab_row_is_redundant(tab, tab->con[r].index)) {
- isl_tab_mark_redundant(tab, tab->con[r].index);
+ if (isl_tab_mark_redundant(tab, tab->con[r].index) < 0)
+ goto error;
return tab;
}
tab = restore_lexmin(tab);
if (tab && !tab->empty && tab->con[r].is_row &&
isl_tab_row_is_redundant(tab, tab->con[r].index))
- isl_tab_mark_redundant(tab, tab->con[r].index);
+ if (isl_tab_mark_redundant(tab, tab->con[r].index) < 0)
+ goto error;
return tab;
error:
isl_tab_free(tab);
int i;
unsigned off = 2 + tab->M;
- for (i = 0; i < tab->n_col; ++i) {
+ for (i = tab->n_dead; i < tab->n_col; ++i) {
if (tab->col_var[i] >= 0 &&
(tab->col_var[i] < tab->n_param ||
tab->col_var[i] >= tab->n_var - tab->n_div))
#define I_PAR 1 << 1
#define I_VAR 1 << 2
-/* Check for first (non-parameter) variable that is non-integer and
- * therefore requires a cut.
+/* Check for next (non-parameter) variable after "var" (first if var == -1)
+ * that is non-integer and therefore requires a cut and return
+ * the index of the variable.
* For parametric tableaus, there are three parts in a row,
* the constant, the coefficients of the parameters and the rest.
* For each part, we check whether the coefficients in that part
* current sample value is integral and no cut is required
* (irrespective of whether the variable part is integral).
*/
-static int first_non_integer(struct isl_tab *tab, int *f)
+static int next_non_integer_var(struct isl_tab *tab, int var, int *f)
{
- int i;
+ var = var < 0 ? tab->n_param : var + 1;
- for (i = tab->n_param; i < tab->n_var - tab->n_div; ++i) {
+ for (; var < tab->n_var - tab->n_div; ++var) {
int flags = 0;
int row;
- if (!tab->var[i].is_row)
+ if (!tab->var[var].is_row)
continue;
- row = tab->var[i].index;
+ row = tab->var[var].index;
if (integer_constant(tab, row))
ISL_FL_SET(flags, I_CST);
if (integer_parameter(tab, row))
if (integer_variable(tab, row))
ISL_FL_SET(flags, I_VAR);
*f = flags;
- return row;
+ return var;
}
return -1;
}
+/* Check for first (non-parameter) variable that is non-integer and
+ * therefore requires a cut and return the corresponding row.
+ * For parametric tableaus, there are three parts in a row,
+ * the constant, the coefficients of the parameters and the rest.
+ * For each part, we check whether the coefficients in that part
+ * are all integral and if so, set the corresponding flag in *f.
+ * If the constant and the parameter part are integral, then the
+ * current sample value is integral and no cut is required
+ * (irrespective of whether the variable part is integral).
+ */
+static int first_non_integer_row(struct isl_tab *tab, int *f)
+{
+ int var = next_non_integer_var(tab, -1, f);
+
+ return var < 0 ? -1 : tab->var[var].index;
+}
+
/* Add a (non-parametric) cut to cut away the non-integral sample
* value of the given row.
*
tab->mat->row[row][off + i], tab->mat->row[row][0]);
tab->con[r].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]) < 0)
+ return -1;
if (tab->row_sign)
tab->row_sign[tab->con[r].index] = isl_tab_row_neg;
* sample point is obtained or until the tableau is determined
* to be integer infeasible.
* As long as there is any non-integer value in the sample point,
- * we add an appropriate cut, if possible and resolve the violated
- * cut constraint using restore_lexmin.
+ * we add appropriate cuts, if possible, for each of these
+ * non-integer values and then resolve the violated
+ * cut constraints using restore_lexmin.
* If one of the corresponding rows is equal to an integral
* combination of variables/constraints plus a non-integral constant,
- * then there is no way to obtain an integer point an we return
+ * then there is no way to obtain an integer point and we return
* a tableau that is marked empty.
*/
static struct isl_tab *cut_to_integer_lexmin(struct isl_tab *tab)
{
+ int var;
int row;
int flags;
if (tab->empty)
return tab;
- while ((row = first_non_integer(tab, &flags)) != -1) {
- if (ISL_FL_ISSET(flags, I_VAR))
- return isl_tab_mark_empty(tab);
- row = add_cut(tab, row);
- if (row < 0)
- goto error;
+ while ((var = next_non_integer_var(tab, -1, &flags)) != -1) {
+ do {
+ if (ISL_FL_ISSET(flags, I_VAR)) {
+ if (isl_tab_mark_empty(tab) < 0)
+ goto error;
+ return tab;
+ }
+ row = tab->var[var].index;
+ row = add_cut(tab, row);
+ if (row < 0)
+ goto error;
+ } while ((var = next_non_integer_var(tab, var, &flags)) != -1);
tab = restore_lexmin(tab);
if (!tab || tab->empty)
break;
return NULL;
}
-static struct isl_tab *drop_sample(struct isl_tab *tab, int s)
-{
- if (s != tab->n_outside)
- isl_mat_swap_rows(tab->samples, tab->n_outside, s);
- tab->n_outside++;
- isl_tab_push(tab, isl_tab_undo_drop_sample);
-
- return tab;
-}
-
/* Check whether all the currently active samples also satisfy the inequality
* "ineq" (treated as an equality if eq is set).
* Remove those samples that do not.
if (!tab)
return NULL;
- isl_assert(tab->mat->ctx, tab->bset, goto error);
+ isl_assert(tab->mat->ctx, tab->bmap, goto error);
isl_assert(tab->mat->ctx, tab->samples, goto error);
isl_assert(tab->mat->ctx, tab->samples->n_col == 1 + tab->n_var, goto error);
sgn = isl_int_sgn(v);
if (eq ? (sgn == 0) : (sgn >= 0))
continue;
- tab = drop_sample(tab, i);
+ tab = isl_tab_drop_sample(tab, i);
if (!tab)
break;
}
}
/* Check if the context tableau of sol has any integer points.
- * Returns -1 if an error occurred.
+ * Leave tab in empty state if no integer point can be found.
* If an integer point can be found and if moreover it is finite,
* then it is added to the list of sample values.
*
* This function is only called when none of the currently active sample
* values satisfies the most recently added constraint.
*/
-static int context_is_feasible(struct isl_sol *sol)
+static struct isl_tab *check_integer_feasible(struct isl_tab *tab)
{
struct isl_tab_undo *snap;
- struct isl_tab *tab;
int feasible;
- if (!sol || !sol->context_tab)
- return -1;
+ if (!tab)
+ return NULL;
- snap = isl_tab_snap(sol->context_tab);
- isl_tab_push_basis(sol->context_tab);
+ snap = isl_tab_snap(tab);
+ if (isl_tab_push_basis(tab) < 0)
+ goto error;
- sol->context_tab = cut_to_integer_lexmin(sol->context_tab);
- if (!sol->context_tab)
+ tab = cut_to_integer_lexmin(tab);
+ if (!tab)
goto error;
- tab = sol->context_tab;
if (!tab->empty && sample_is_finite(tab)) {
struct isl_vec *sample;
- tab->samples = isl_mat_extend(tab->samples,
- tab->n_sample + 1, tab->samples->n_col);
- if (!tab->samples)
- goto error;
-
sample = isl_tab_get_sample_value(tab);
- if (!sample)
- goto error;
- isl_seq_cpy(tab->samples->row[tab->n_sample],
- sample->el, sample->size);
- isl_vec_free(sample);
- tab->n_sample++;
+
+ tab = isl_tab_add_sample(tab, sample);
}
- feasible = !sol->context_tab->empty;
- if (isl_tab_rollback(sol->context_tab, snap) < 0)
+ if (!tab->empty && isl_tab_rollback(tab, snap) < 0)
goto error;
- return feasible;
+ return tab;
error:
- isl_tab_free(sol->context_tab);
- sol->context_tab = NULL;
- return -1;
+ isl_tab_free(tab);
+ return NULL;
}
-/* First check if any of the currently active sample values satisfies
+/* Check if any of the currently active sample values satisfies
* the inequality "ineq" (an equality if eq is set).
- * If not, continue with check_integer_feasible.
*/
-static int context_valid_sample_or_feasible(struct isl_sol *sol,
- isl_int *ineq, int eq)
+static int tab_has_valid_sample(struct isl_tab *tab, isl_int *ineq, int eq)
{
int i;
isl_int v;
- struct isl_tab *tab;
- if (!sol || !sol->context_tab)
+ if (!tab)
return -1;
- tab = sol->context_tab;
- isl_assert(tab->mat->ctx, tab->bset, return -1);
+ isl_assert(tab->mat->ctx, tab->bmap, return -1);
isl_assert(tab->mat->ctx, tab->samples, return -1);
isl_assert(tab->mat->ctx, tab->samples->n_col == 1 + tab->n_var, return -1);
}
isl_int_clear(v);
- if (i < tab->n_sample)
- return 1;
-
- return context_is_feasible(sol);
+ return i < tab->n_sample;
}
-/* For a div d = floor(f/m), 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
+/* Add a div specifed by "div" to the tableau "tab" and return
+ * 1 if the div is obviously non-negative.
*/
-static struct isl_tab *add_div_constraints(struct isl_tab *tab, unsigned div)
+static int context_tab_add_div(struct isl_tab *tab, struct isl_vec *div,
+ int (*add_ineq)(void *user, isl_int *), void *user)
{
- unsigned total;
- unsigned div_pos;
- struct isl_vec *ineq;
-
- if (!tab)
- return NULL;
-
- total = isl_basic_set_total_dim(tab->bset);
- div_pos = 1 + total - tab->bset->n_div + div;
-
- ineq = ineq_for_div(tab->bset, div);
- if (!ineq)
- goto error;
-
- tab = add_lexmin_ineq(tab, ineq->el);
+ int i;
+ int r;
+ struct isl_mat *samples;
+ int nonneg;
- isl_seq_neg(ineq->el, tab->bset->div[div] + 1, 1 + total);
- isl_int_set(ineq->el[div_pos], tab->bset->div[div][0]);
- isl_int_add(ineq->el[0], ineq->el[0], ineq->el[div_pos]);
- isl_int_sub_ui(ineq->el[0], ineq->el[0], 1);
- tab = add_lexmin_ineq(tab, ineq->el);
+ r = isl_tab_add_div(tab, div, add_ineq, user);
+ if (r < 0)
+ return -1;
+ nonneg = tab->var[r].is_nonneg;
+ tab->var[r].frozen = 1;
- isl_vec_free(ineq);
+ samples = isl_mat_extend(tab->samples,
+ tab->n_sample, 1 + tab->n_var);
+ tab->samples = samples;
+ if (!samples)
+ return -1;
+ for (i = tab->n_outside; i < samples->n_row; ++i) {
+ isl_seq_inner_product(div->el + 1, samples->row[i],
+ div->size - 1, &samples->row[i][samples->n_col - 1]);
+ isl_int_fdiv_q(samples->row[i][samples->n_col - 1],
+ samples->row[i][samples->n_col - 1], div->el[0]);
+ }
- return tab;
-error:
- isl_tab_free(tab);
- return NULL;
+ return nonneg;
}
/* Add a div specified by "div" to both the main tableau and
* need to express the meaning of the div.
* Return the index of the div or -1 if anything went wrong.
*/
-static int add_div(struct isl_tab *tab, struct isl_tab **context_tab,
+static int add_div(struct isl_tab *tab, struct isl_context *context,
struct isl_vec *div)
{
- int i;
int r;
- int k;
- struct isl_mat *samples;
-
- if (isl_tab_extend_vars(*context_tab, 1) < 0)
- goto error;
- r = isl_tab_allocate_var(*context_tab);
- if (r < 0)
- goto error;
- (*context_tab)->var[r].is_nonneg = 1;
- (*context_tab)->var[r].frozen = 1;
+ int nonneg;
- samples = isl_mat_extend((*context_tab)->samples,
- (*context_tab)->n_sample, 1 + (*context_tab)->n_var);
- (*context_tab)->samples = samples;
- if (!samples)
+ if ((nonneg = context->op->add_div(context, div)) < 0)
goto error;
- for (i = (*context_tab)->n_outside; i < samples->n_row; ++i) {
- isl_seq_inner_product(div->el + 1, samples->row[i],
- div->size - 1, &samples->row[i][samples->n_col - 1]);
- isl_int_fdiv_q(samples->row[i][samples->n_col - 1],
- samples->row[i][samples->n_col - 1], div->el[0]);
- }
- (*context_tab)->bset = isl_basic_set_extend_dim((*context_tab)->bset,
- isl_basic_set_get_dim((*context_tab)->bset), 1, 0, 2);
- k = isl_basic_set_alloc_div((*context_tab)->bset);
- if (k < 0)
- goto error;
- isl_seq_cpy((*context_tab)->bset->div[k], div->el, div->size);
- isl_tab_push((*context_tab), isl_tab_undo_bset_div);
- *context_tab = add_div_constraints(*context_tab, k);
- if (!*context_tab)
+ if (!context->op->is_ok(context))
goto error;
if (isl_tab_extend_vars(tab, 1) < 0)
r = isl_tab_allocate_var(tab);
if (r < 0)
goto error;
- if (!(*context_tab)->M)
+ if (nonneg)
tab->var[r].is_nonneg = 1;
tab->var[r].frozen = 1;
tab->n_div++;
return tab->n_div - 1;
error:
- isl_tab_free(*context_tab);
- *context_tab = NULL;
+ context->op->invalidate(context);
return -1;
}
static int find_div(struct isl_tab *tab, isl_int *div, isl_int denom)
{
int i;
- unsigned total = isl_basic_set_total_dim(tab->bset);
+ unsigned total = isl_basic_map_total_dim(tab->bmap);
- for (i = 0; i < tab->bset->n_div; ++i) {
- if (isl_int_ne(tab->bset->div[i][0], denom))
+ for (i = 0; i < tab->bmap->n_div; ++i) {
+ if (isl_int_ne(tab->bmap->div[i][0], denom))
continue;
- if (!isl_seq_eq(tab->bset->div[i] + 1, div, total))
+ if (!isl_seq_eq(tab->bmap->div[i] + 1, div, 1 + total))
continue;
return i;
}
/* Return the index of a div that corresponds to "div".
* We first check if we already have such a div and if not, we create one.
*/
-static int get_div(struct isl_tab *tab, struct isl_tab **context_tab,
+static int get_div(struct isl_tab *tab, struct isl_context *context,
struct isl_vec *div)
{
int d;
+ struct isl_tab *context_tab = context->op->peek_tab(context);
+
+ if (!context_tab)
+ return -1;
- d = find_div(*context_tab, div->el + 1, div->el[0]);
+ d = find_div(context_tab, div->el + 1, div->el[0]);
if (d != -1)
return d;
- return add_div(tab, context_tab, div);
+ return add_div(tab, context, div);
}
/* Add a parametric cut to cut away the non-integral sample value
* Return the row of the cut or -1.
*/
static int add_parametric_cut(struct isl_tab *tab, int row,
- struct isl_tab **context_tab)
+ struct isl_context *context)
{
struct isl_vec *div;
int d;
int r;
isl_int *r_row;
int col;
+ int n;
unsigned off = 2 + tab->M;
- if (!*context_tab)
- goto error;
-
- if (isl_tab_extend_cons(*context_tab, 3) < 0)
- goto error;
+ if (!context)
+ return -1;
div = get_row_parameter_div(tab, row);
if (!div)
return -1;
- d = get_div(tab, context_tab, div);
+ n = tab->n_div;
+ d = context->op->get_div(context, tab, div);
if (d < 0)
- goto error;
+ return -1;
if (isl_tab_extend_cons(tab, 1) < 0)
return -1;
}
tab->con[r].is_nonneg = 1;
- isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ if (isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]) < 0)
+ return -1;
if (tab->row_sign)
tab->row_sign[tab->con[r].index] = isl_tab_row_neg;
isl_vec_free(div);
- return tab->con[r].index;
-error:
- isl_tab_free(*context_tab);
- *context_tab = NULL;
- return -1;
+ row = tab->con[r].index;
+
+ if (d >= n && context->op->detect_equalities(context, tab) < 0)
+ return -1;
+
+ return row;
}
/* Construct a tableau for bmap that can be used for computing
if (!tab->row_sign)
goto error;
}
- if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
- return isl_tab_mark_empty(tab);
+ if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY)) {
+ if (isl_tab_mark_empty(tab) < 0)
+ goto error;
+ return tab;
+ }
for (i = tab->n_param; i < tab->n_var - tab->n_div; ++i) {
tab->var[i].is_nonneg = 1;
return NULL;
}
-static struct isl_tab *context_tab_for_lexmin(struct isl_basic_set *bset)
+/* Given a main tableau where more than one row requires a split,
+ * determine and return the "best" row to split on.
+ *
+ * Given two rows in the main tableau, if the inequality corresponding
+ * to the first row is redundant with respect to that of the second row
+ * in the current tableau, then it is better to split on the second row,
+ * since in the positive part, both row will be positive.
+ * (In the negative part a pivot will have to be performed and just about
+ * anything can happen to the sign of the other row.)
+ *
+ * As a simple heuristic, we therefore select the row that makes the most
+ * of the other rows redundant.
+ *
+ * Perhaps it would also be useful to look at the number of constraints
+ * that conflict with any given constraint.
+ */
+static int best_split(struct isl_tab *tab, struct isl_tab *context_tab)
{
- struct isl_tab *tab;
+ struct isl_tab_undo *snap;
+ int split;
+ int row;
+ int best = -1;
+ int best_r;
- bset = isl_basic_set_cow(bset);
- if (!bset)
- return NULL;
- tab = tab_for_lexmin((struct isl_basic_map *)bset, NULL, 1, 0);
- if (!tab)
- goto error;
- tab->bset = bset;
- tab->n_sample = 0;
- tab->n_outside = 0;
- tab->samples = isl_mat_alloc(bset->ctx, 1, 1 + tab->n_var);
- if (!tab->samples)
- goto error;
- return tab;
+ if (isl_tab_extend_cons(context_tab, 2) < 0)
+ return -1;
+
+ snap = isl_tab_snap(context_tab);
+
+ for (split = tab->n_redundant; split < tab->n_row; ++split) {
+ struct isl_tab_undo *snap2;
+ struct isl_vec *ineq = NULL;
+ int r = 0;
+ int ok;
+
+ if (!isl_tab_var_from_row(tab, split)->is_nonneg)
+ continue;
+ if (tab->row_sign[split] != isl_tab_row_any)
+ continue;
+
+ ineq = get_row_parameter_ineq(tab, split);
+ if (!ineq)
+ return -1;
+ ok = isl_tab_add_ineq(context_tab, ineq->el) >= 0;
+ isl_vec_free(ineq);
+ if (!ok)
+ return -1;
+
+ snap2 = isl_tab_snap(context_tab);
+
+ for (row = tab->n_redundant; row < tab->n_row; ++row) {
+ struct isl_tab_var *var;
+
+ if (row == split)
+ continue;
+ if (!isl_tab_var_from_row(tab, row)->is_nonneg)
+ continue;
+ if (tab->row_sign[row] != isl_tab_row_any)
+ continue;
+
+ ineq = get_row_parameter_ineq(tab, row);
+ if (!ineq)
+ return -1;
+ ok = isl_tab_add_ineq(context_tab, ineq->el) >= 0;
+ isl_vec_free(ineq);
+ if (!ok)
+ return -1;
+ var = &context_tab->con[context_tab->n_con - 1];
+ if (!context_tab->empty &&
+ !isl_tab_min_at_most_neg_one(context_tab, var))
+ r++;
+ if (isl_tab_rollback(context_tab, snap2) < 0)
+ return -1;
+ }
+ if (best == -1 || r > best_r) {
+ best = split;
+ best_r = r;
+ }
+ if (isl_tab_rollback(context_tab, snap) < 0)
+ return -1;
+ }
+
+ return best;
+}
+
+static struct isl_basic_set *context_lex_peek_basic_set(
+ struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ if (!clex->tab)
+ return NULL;
+ return isl_tab_peek_bset(clex->tab);
+}
+
+static struct isl_tab *context_lex_peek_tab(struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ return clex->tab;
+}
+
+static void context_lex_extend(struct isl_context *context, int n)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ if (!clex->tab)
+ return;
+ if (isl_tab_extend_cons(clex->tab, n) >= 0)
+ return;
+ isl_tab_free(clex->tab);
+ clex->tab = NULL;
+}
+
+static void context_lex_add_eq(struct isl_context *context, isl_int *eq,
+ int check, int update)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ if (isl_tab_extend_cons(clex->tab, 2) < 0)
+ goto error;
+ clex->tab = add_lexmin_eq(clex->tab, eq);
+ if (check) {
+ int v = tab_has_valid_sample(clex->tab, eq, 1);
+ if (v < 0)
+ goto error;
+ if (!v)
+ clex->tab = check_integer_feasible(clex->tab);
+ }
+ if (update)
+ clex->tab = check_samples(clex->tab, eq, 1);
+ return;
+error:
+ isl_tab_free(clex->tab);
+ clex->tab = NULL;
+}
+
+static void context_lex_add_ineq(struct isl_context *context, isl_int *ineq,
+ int check, int update)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ if (isl_tab_extend_cons(clex->tab, 1) < 0)
+ goto error;
+ clex->tab = add_lexmin_ineq(clex->tab, ineq);
+ if (check) {
+ int v = tab_has_valid_sample(clex->tab, ineq, 0);
+ if (v < 0)
+ goto error;
+ if (!v)
+ clex->tab = check_integer_feasible(clex->tab);
+ }
+ if (update)
+ clex->tab = check_samples(clex->tab, ineq, 0);
+ return;
+error:
+ isl_tab_free(clex->tab);
+ clex->tab = NULL;
+}
+
+static int context_lex_add_ineq_wrap(void *user, isl_int *ineq)
+{
+ struct isl_context *context = (struct isl_context *)user;
+ context_lex_add_ineq(context, ineq, 0, 0);
+ return context->op->is_ok(context) ? 0 : -1;
+}
+
+/* Check which signs can be obtained by "ineq" on all the currently
+ * active sample values. See row_sign for more information.
+ */
+static enum isl_tab_row_sign tab_ineq_sign(struct isl_tab *tab, isl_int *ineq,
+ int strict)
+{
+ int i;
+ int sgn;
+ isl_int tmp;
+ enum isl_tab_row_sign res = isl_tab_row_unknown;
+
+ isl_assert(tab->mat->ctx, tab->samples, return isl_tab_row_unknown);
+ isl_assert(tab->mat->ctx, tab->samples->n_col == 1 + tab->n_var,
+ return isl_tab_row_unknown);
+
+ isl_int_init(tmp);
+ for (i = tab->n_outside; i < tab->n_sample; ++i) {
+ isl_seq_inner_product(tab->samples->row[i], ineq,
+ 1 + tab->n_var, &tmp);
+ sgn = isl_int_sgn(tmp);
+ if (sgn > 0 || (sgn == 0 && strict)) {
+ if (res == isl_tab_row_unknown)
+ res = isl_tab_row_pos;
+ if (res == isl_tab_row_neg)
+ res = isl_tab_row_any;
+ }
+ if (sgn < 0) {
+ if (res == isl_tab_row_unknown)
+ res = isl_tab_row_neg;
+ if (res == isl_tab_row_pos)
+ res = isl_tab_row_any;
+ }
+ if (res == isl_tab_row_any)
+ break;
+ }
+ isl_int_clear(tmp);
+
+ return res;
+}
+
+static enum isl_tab_row_sign context_lex_ineq_sign(struct isl_context *context,
+ isl_int *ineq, int strict)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ return tab_ineq_sign(clex->tab, ineq, strict);
+}
+
+/* Check whether "ineq" can be added to the tableau without rendering
+ * it infeasible.
+ */
+static int context_lex_test_ineq(struct isl_context *context, isl_int *ineq)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ struct isl_tab_undo *snap;
+ int feasible;
+
+ if (!clex->tab)
+ return -1;
+
+ if (isl_tab_extend_cons(clex->tab, 1) < 0)
+ return -1;
+
+ snap = isl_tab_snap(clex->tab);
+ if (isl_tab_push_basis(clex->tab) < 0)
+ return -1;
+ clex->tab = add_lexmin_ineq(clex->tab, ineq);
+ clex->tab = check_integer_feasible(clex->tab);
+ if (!clex->tab)
+ return -1;
+ feasible = !clex->tab->empty;
+ if (isl_tab_rollback(clex->tab, snap) < 0)
+ return -1;
+
+ return feasible;
+}
+
+static int context_lex_get_div(struct isl_context *context, struct isl_tab *tab,
+ struct isl_vec *div)
+{
+ return get_div(tab, context, div);
+}
+
+static int context_lex_add_div(struct isl_context *context, struct isl_vec *div)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ return context_tab_add_div(clex->tab, div,
+ context_lex_add_ineq_wrap, context);
+}
+
+static int context_lex_detect_equalities(struct isl_context *context,
+ struct isl_tab *tab)
+{
+ return 0;
+}
+
+static int context_lex_best_split(struct isl_context *context,
+ struct isl_tab *tab)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ struct isl_tab_undo *snap;
+ int r;
+
+ snap = isl_tab_snap(clex->tab);
+ if (isl_tab_push_basis(clex->tab) < 0)
+ return -1;
+ r = best_split(tab, clex->tab);
+
+ if (isl_tab_rollback(clex->tab, snap) < 0)
+ return -1;
+
+ return r;
+}
+
+static int context_lex_is_empty(struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ if (!clex->tab)
+ return -1;
+ return clex->tab->empty;
+}
+
+static void *context_lex_save(struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ struct isl_tab_undo *snap;
+
+ snap = isl_tab_snap(clex->tab);
+ if (isl_tab_push_basis(clex->tab) < 0)
+ return NULL;
+ if (isl_tab_save_samples(clex->tab) < 0)
+ return NULL;
+
+ return snap;
+}
+
+static void context_lex_restore(struct isl_context *context, void *save)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ if (isl_tab_rollback(clex->tab, (struct isl_tab_undo *)save) < 0) {
+ isl_tab_free(clex->tab);
+ clex->tab = NULL;
+ }
+}
+
+static int context_lex_is_ok(struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ return !!clex->tab;
+}
+
+/* For each variable in the context tableau, check if the variable can
+ * only attain non-negative values. If so, mark the parameter as non-negative
+ * in the main tableau. This allows for a more direct identification of some
+ * cases of violated constraints.
+ */
+static struct isl_tab *tab_detect_nonnegative_parameters(struct isl_tab *tab,
+ struct isl_tab *context_tab)
+{
+ int i;
+ struct isl_tab_undo *snap;
+ struct isl_vec *ineq = NULL;
+ struct isl_tab_var *var;
+ int n;
+
+ if (context_tab->n_var == 0)
+ return tab;
+
+ ineq = isl_vec_alloc(tab->mat->ctx, 1 + context_tab->n_var);
+ if (!ineq)
+ goto error;
+
+ if (isl_tab_extend_cons(context_tab, 1) < 0)
+ goto error;
+
+ snap = isl_tab_snap(context_tab);
+
+ n = 0;
+ isl_seq_clr(ineq->el, ineq->size);
+ for (i = 0; i < context_tab->n_var; ++i) {
+ isl_int_set_si(ineq->el[1 + i], 1);
+ if (isl_tab_add_ineq(context_tab, ineq->el) < 0)
+ goto error;
+ var = &context_tab->con[context_tab->n_con - 1];
+ if (!context_tab->empty &&
+ !isl_tab_min_at_most_neg_one(context_tab, var)) {
+ int j = i;
+ if (i >= tab->n_param)
+ j = i - tab->n_param + tab->n_var - tab->n_div;
+ tab->var[j].is_nonneg = 1;
+ n++;
+ }
+ isl_int_set_si(ineq->el[1 + i], 0);
+ if (isl_tab_rollback(context_tab, snap) < 0)
+ goto error;
+ }
+
+ if (context_tab->M && n == context_tab->n_var) {
+ context_tab->mat = isl_mat_drop_cols(context_tab->mat, 2, 1);
+ context_tab->M = 0;
+ }
+
+ isl_vec_free(ineq);
+ return tab;
+error:
+ isl_vec_free(ineq);
+ isl_tab_free(tab);
+ return NULL;
+}
+
+static struct isl_tab *context_lex_detect_nonnegative_parameters(
+ struct isl_context *context, struct isl_tab *tab)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ struct isl_tab_undo *snap;
+
+ snap = isl_tab_snap(clex->tab);
+ if (isl_tab_push_basis(clex->tab) < 0)
+ goto error;
+
+ tab = tab_detect_nonnegative_parameters(tab, clex->tab);
+
+ if (isl_tab_rollback(clex->tab, snap) < 0)
+ goto error;
+
+ return tab;
+error:
+ isl_tab_free(tab);
+ return NULL;
+}
+
+static void context_lex_invalidate(struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ isl_tab_free(clex->tab);
+ clex->tab = NULL;
+}
+
+static void context_lex_free(struct isl_context *context)
+{
+ struct isl_context_lex *clex = (struct isl_context_lex *)context;
+ isl_tab_free(clex->tab);
+ free(clex);
+}
+
+struct isl_context_op isl_context_lex_op = {
+ context_lex_detect_nonnegative_parameters,
+ context_lex_peek_basic_set,
+ context_lex_peek_tab,
+ context_lex_add_eq,
+ context_lex_add_ineq,
+ context_lex_ineq_sign,
+ context_lex_test_ineq,
+ context_lex_get_div,
+ context_lex_add_div,
+ context_lex_detect_equalities,
+ context_lex_best_split,
+ context_lex_is_empty,
+ context_lex_is_ok,
+ context_lex_save,
+ context_lex_restore,
+ context_lex_invalidate,
+ context_lex_free,
+};
+
+static struct isl_tab *context_tab_for_lexmin(struct isl_basic_set *bset)
+{
+ struct isl_tab *tab;
+
+ bset = isl_basic_set_cow(bset);
+ if (!bset)
+ return NULL;
+ tab = tab_for_lexmin((struct isl_basic_map *)bset, NULL, 1, 0);
+ if (!tab)
+ goto error;
+ if (isl_tab_track_bset(tab, bset) < 0)
+ goto error;
+ tab = isl_tab_init_samples(tab);
+ return tab;
+error:
+ isl_basic_set_free(bset);
+ return NULL;
+}
+
+static struct isl_context *isl_context_lex_alloc(struct isl_basic_set *dom)
+{
+ struct isl_context_lex *clex;
+
+ if (!dom)
+ return NULL;
+
+ clex = isl_alloc_type(dom->ctx, struct isl_context_lex);
+ if (!clex)
+ return NULL;
+
+ clex->context.op = &isl_context_lex_op;
+
+ clex->tab = context_tab_for_lexmin(isl_basic_set_copy(dom));
+ clex->tab = restore_lexmin(clex->tab);
+ clex->tab = check_integer_feasible(clex->tab);
+ if (!clex->tab)
+ goto error;
+
+ return &clex->context;
+error:
+ clex->context.op->free(&clex->context);
+ return NULL;
+}
+
+struct isl_context_gbr {
+ struct isl_context context;
+ struct isl_tab *tab;
+ struct isl_tab *shifted;
+ struct isl_tab *cone;
+};
+
+static struct isl_tab *context_gbr_detect_nonnegative_parameters(
+ struct isl_context *context, struct isl_tab *tab)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ return tab_detect_nonnegative_parameters(tab, cgbr->tab);
+}
+
+static struct isl_basic_set *context_gbr_peek_basic_set(
+ struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ if (!cgbr->tab)
+ return NULL;
+ return isl_tab_peek_bset(cgbr->tab);
+}
+
+static struct isl_tab *context_gbr_peek_tab(struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ return cgbr->tab;
+}
+
+/* Initialize the "shifted" tableau of the context, which
+ * contains the constraints of the original tableau shifted
+ * by the sum of all negative coefficients. This ensures
+ * that any rational point in the shifted tableau can
+ * be rounded up to yield an integer point in the original tableau.
+ */
+static void gbr_init_shifted(struct isl_context_gbr *cgbr)
+{
+ int i, j;
+ struct isl_vec *cst;
+ struct isl_basic_set *bset = isl_tab_peek_bset(cgbr->tab);
+ unsigned dim = isl_basic_set_total_dim(bset);
+
+ cst = isl_vec_alloc(cgbr->tab->mat->ctx, bset->n_ineq);
+ if (!cst)
+ return;
+
+ for (i = 0; i < bset->n_ineq; ++i) {
+ isl_int_set(cst->el[i], bset->ineq[i][0]);
+ for (j = 0; j < dim; ++j) {
+ if (!isl_int_is_neg(bset->ineq[i][1 + j]))
+ continue;
+ isl_int_add(bset->ineq[i][0], bset->ineq[i][0],
+ bset->ineq[i][1 + j]);
+ }
+ }
+
+ cgbr->shifted = isl_tab_from_basic_set(bset);
+
+ for (i = 0; i < bset->n_ineq; ++i)
+ isl_int_set(bset->ineq[i][0], cst->el[i]);
+
+ isl_vec_free(cst);
+}
+
+/* Check if the shifted tableau is non-empty, and if so
+ * use the sample point to construct an integer point
+ * of the context tableau.
+ */
+static struct isl_vec *gbr_get_shifted_sample(struct isl_context_gbr *cgbr)
+{
+ struct isl_vec *sample;
+
+ if (!cgbr->shifted)
+ gbr_init_shifted(cgbr);
+ if (!cgbr->shifted)
+ return NULL;
+ if (cgbr->shifted->empty)
+ return isl_vec_alloc(cgbr->tab->mat->ctx, 0);
+
+ sample = isl_tab_get_sample_value(cgbr->shifted);
+ sample = isl_vec_ceil(sample);
+
+ return sample;
+}
+
+static struct isl_basic_set *drop_constant_terms(struct isl_basic_set *bset)
+{
+ int i;
+
+ if (!bset)
+ return NULL;
+
+ for (i = 0; i < bset->n_eq; ++i)
+ isl_int_set_si(bset->eq[i][0], 0);
+
+ for (i = 0; i < bset->n_ineq; ++i)
+ isl_int_set_si(bset->ineq[i][0], 0);
+
+ return bset;
+}
+
+static int use_shifted(struct isl_context_gbr *cgbr)
+{
+ return cgbr->tab->bmap->n_eq == 0 && cgbr->tab->bmap->n_div == 0;
+}
+
+static struct isl_vec *gbr_get_sample(struct isl_context_gbr *cgbr)
+{
+ struct isl_basic_set *bset;
+ struct isl_basic_set *cone;
+
+ if (isl_tab_sample_is_integer(cgbr->tab))
+ return isl_tab_get_sample_value(cgbr->tab);
+
+ if (use_shifted(cgbr)) {
+ struct isl_vec *sample;
+
+ sample = gbr_get_shifted_sample(cgbr);
+ if (!sample || sample->size > 0)
+ return sample;
+
+ isl_vec_free(sample);
+ }
+
+ if (!cgbr->cone) {
+ bset = isl_tab_peek_bset(cgbr->tab);
+ cgbr->cone = isl_tab_from_recession_cone(bset, 0);
+ if (!cgbr->cone)
+ return NULL;
+ if (isl_tab_track_bset(cgbr->cone, isl_basic_set_dup(bset)) < 0)
+ return NULL;
+ }
+ if (isl_tab_detect_implicit_equalities(cgbr->cone) < 0)
+ return NULL;
+
+ if (cgbr->cone->n_dead == cgbr->cone->n_col) {
+ struct isl_vec *sample;
+ struct isl_tab_undo *snap;
+
+ if (cgbr->tab->basis) {
+ if (cgbr->tab->basis->n_col != 1 + cgbr->tab->n_var) {
+ isl_mat_free(cgbr->tab->basis);
+ cgbr->tab->basis = NULL;
+ }
+ cgbr->tab->n_zero = 0;
+ cgbr->tab->n_unbounded = 0;
+ }
+
+ snap = isl_tab_snap(cgbr->tab);
+
+ sample = isl_tab_sample(cgbr->tab);
+
+ if (isl_tab_rollback(cgbr->tab, snap) < 0) {
+ isl_vec_free(sample);
+ return NULL;
+ }
+
+ return sample;
+ }
+
+ cone = isl_basic_set_dup(isl_tab_peek_bset(cgbr->cone));
+ cone = drop_constant_terms(cone);
+ cone = isl_basic_set_update_from_tab(cone, cgbr->cone);
+ cone = isl_basic_set_underlying_set(cone);
+ cone = isl_basic_set_gauss(cone, NULL);
+
+ bset = isl_basic_set_dup(isl_tab_peek_bset(cgbr->tab));
+ bset = isl_basic_set_update_from_tab(bset, cgbr->tab);
+ bset = isl_basic_set_underlying_set(bset);
+ bset = isl_basic_set_gauss(bset, NULL);
+
+ return isl_basic_set_sample_with_cone(bset, cone);
+}
+
+static void check_gbr_integer_feasible(struct isl_context_gbr *cgbr)
+{
+ struct isl_vec *sample;
+
+ if (!cgbr->tab)
+ return;
+
+ if (cgbr->tab->empty)
+ return;
+
+ sample = gbr_get_sample(cgbr);
+ if (!sample)
+ goto error;
+
+ if (sample->size == 0) {
+ isl_vec_free(sample);
+ if (isl_tab_mark_empty(cgbr->tab) < 0)
+ goto error;
+ return;
+ }
+
+ cgbr->tab = isl_tab_add_sample(cgbr->tab, sample);
+
+ return;
+error:
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static struct isl_tab *add_gbr_eq(struct isl_tab *tab, isl_int *eq)
+{
+ int r;
+
+ if (!tab)
+ return NULL;
+
+ if (isl_tab_extend_cons(tab, 2) < 0)
+ goto error;
+
+ if (isl_tab_add_eq(tab, eq) < 0)
+ goto error;
+
+ return tab;
+error:
+ isl_tab_free(tab);
+ return NULL;
+}
+
+static void context_gbr_add_eq(struct isl_context *context, isl_int *eq,
+ int check, int update)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+
+ cgbr->tab = add_gbr_eq(cgbr->tab, eq);
+
+ if (cgbr->cone && cgbr->cone->n_col != cgbr->cone->n_dead) {
+ if (isl_tab_extend_cons(cgbr->cone, 2) < 0)
+ goto error;
+ if (isl_tab_add_eq(cgbr->cone, eq) < 0)
+ goto error;
+ }
+
+ if (check) {
+ int v = tab_has_valid_sample(cgbr->tab, eq, 1);
+ if (v < 0)
+ goto error;
+ if (!v)
+ check_gbr_integer_feasible(cgbr);
+ }
+ if (update)
+ cgbr->tab = check_samples(cgbr->tab, eq, 1);
+ return;
+error:
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static void add_gbr_ineq(struct isl_context_gbr *cgbr, isl_int *ineq)
+{
+ if (!cgbr->tab)
+ return;
+
+ if (isl_tab_extend_cons(cgbr->tab, 1) < 0)
+ goto error;
+
+ if (isl_tab_add_ineq(cgbr->tab, ineq) < 0)
+ goto error;
+
+ if (cgbr->shifted && !cgbr->shifted->empty && use_shifted(cgbr)) {
+ int i;
+ unsigned dim;
+ dim = isl_basic_map_total_dim(cgbr->tab->bmap);
+
+ if (isl_tab_extend_cons(cgbr->shifted, 1) < 0)
+ goto error;
+
+ for (i = 0; i < dim; ++i) {
+ if (!isl_int_is_neg(ineq[1 + i]))
+ continue;
+ isl_int_add(ineq[0], ineq[0], ineq[1 + i]);
+ }
+
+ if (isl_tab_add_ineq(cgbr->shifted, ineq) < 0)
+ goto error;
+
+ for (i = 0; i < dim; ++i) {
+ if (!isl_int_is_neg(ineq[1 + i]))
+ continue;
+ isl_int_sub(ineq[0], ineq[0], ineq[1 + i]);
+ }
+ }
+
+ if (cgbr->cone && cgbr->cone->n_col != cgbr->cone->n_dead) {
+ if (isl_tab_extend_cons(cgbr->cone, 1) < 0)
+ goto error;
+ if (isl_tab_add_ineq(cgbr->cone, ineq) < 0)
+ goto error;
+ }
+
+ return;
+error:
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static void context_gbr_add_ineq(struct isl_context *context, isl_int *ineq,
+ int check, int update)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+
+ add_gbr_ineq(cgbr, ineq);
+ if (!cgbr->tab)
+ return;
+
+ if (check) {
+ int v = tab_has_valid_sample(cgbr->tab, ineq, 0);
+ if (v < 0)
+ goto error;
+ if (!v)
+ check_gbr_integer_feasible(cgbr);
+ }
+ if (update)
+ cgbr->tab = check_samples(cgbr->tab, ineq, 0);
+ return;
+error:
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static int context_gbr_add_ineq_wrap(void *user, isl_int *ineq)
+{
+ struct isl_context *context = (struct isl_context *)user;
+ context_gbr_add_ineq(context, ineq, 0, 0);
+ return context->op->is_ok(context) ? 0 : -1;
+}
+
+static enum isl_tab_row_sign context_gbr_ineq_sign(struct isl_context *context,
+ isl_int *ineq, int strict)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ return tab_ineq_sign(cgbr->tab, ineq, strict);
+}
+
+/* Check whether "ineq" can be added to the tableau without rendering
+ * it infeasible.
+ */
+static int context_gbr_test_ineq(struct isl_context *context, isl_int *ineq)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ struct isl_tab_undo *snap;
+ struct isl_tab_undo *shifted_snap = NULL;
+ struct isl_tab_undo *cone_snap = NULL;
+ int feasible;
+
+ if (!cgbr->tab)
+ return -1;
+
+ if (isl_tab_extend_cons(cgbr->tab, 1) < 0)
+ return -1;
+
+ snap = isl_tab_snap(cgbr->tab);
+ if (cgbr->shifted)
+ shifted_snap = isl_tab_snap(cgbr->shifted);
+ if (cgbr->cone)
+ cone_snap = isl_tab_snap(cgbr->cone);
+ add_gbr_ineq(cgbr, ineq);
+ check_gbr_integer_feasible(cgbr);
+ if (!cgbr->tab)
+ return -1;
+ feasible = !cgbr->tab->empty;
+ if (isl_tab_rollback(cgbr->tab, snap) < 0)
+ return -1;
+ if (shifted_snap) {
+ if (isl_tab_rollback(cgbr->shifted, shifted_snap))
+ return -1;
+ } else if (cgbr->shifted) {
+ isl_tab_free(cgbr->shifted);
+ cgbr->shifted = NULL;
+ }
+ if (cone_snap) {
+ if (isl_tab_rollback(cgbr->cone, cone_snap))
+ return -1;
+ } else if (cgbr->cone) {
+ isl_tab_free(cgbr->cone);
+ cgbr->cone = NULL;
+ }
+
+ return feasible;
+}
+
+/* Return the column of the last of the variables associated to
+ * a column that has a non-zero coefficient.
+ * This function is called in a context where only coefficients
+ * of parameters or divs can be non-zero.
+ */
+static int last_non_zero_var_col(struct isl_tab *tab, isl_int *p)
+{
+ int i;
+ int col;
+ unsigned dim = tab->n_var - tab->n_param - tab->n_div;
+
+ if (tab->n_var == 0)
+ return -1;
+
+ for (i = tab->n_var - 1; i >= 0; --i) {
+ if (i >= tab->n_param && i < tab->n_var - tab->n_div)
+ continue;
+ if (tab->var[i].is_row)
+ continue;
+ col = tab->var[i].index;
+ if (!isl_int_is_zero(p[col]))
+ return col;
+ }
+
+ return -1;
+}
+
+/* Look through all the recently added equalities in the context
+ * to see if we can propagate any of them to the main tableau.
+ *
+ * The newly added equalities in the context are encoded as pairs
+ * of inequalities starting at inequality "first".
+ *
+ * We tentatively add each of these equalities to the main tableau
+ * and if this happens to result in a row with a final coefficient
+ * that is one or negative one, we use it to kill a column
+ * in the main tableau. Otherwise, we discard the tentatively
+ * added row.
+ */
+static void propagate_equalities(struct isl_context_gbr *cgbr,
+ struct isl_tab *tab, unsigned first)
+{
+ int i;
+ struct isl_vec *eq = NULL;
+
+ eq = isl_vec_alloc(tab->mat->ctx, 1 + tab->n_var);
+ if (!eq)
+ goto error;
+
+ if (isl_tab_extend_cons(tab, (cgbr->tab->bmap->n_ineq - first)/2) < 0)
+ goto error;
+
+ isl_seq_clr(eq->el + 1 + tab->n_param,
+ tab->n_var - tab->n_param - tab->n_div);
+ for (i = first; i < cgbr->tab->bmap->n_ineq; i += 2) {
+ int j;
+ int r;
+ struct isl_tab_undo *snap;
+ snap = isl_tab_snap(tab);
+
+ isl_seq_cpy(eq->el, cgbr->tab->bmap->ineq[i], 1 + tab->n_param);
+ isl_seq_cpy(eq->el + 1 + tab->n_var - tab->n_div,
+ cgbr->tab->bmap->ineq[i] + 1 + tab->n_param,
+ tab->n_div);
+
+ r = isl_tab_add_row(tab, eq->el);
+ if (r < 0)
+ goto error;
+ r = tab->con[r].index;
+ j = last_non_zero_var_col(tab, tab->mat->row[r] + 2 + tab->M);
+ if (j < 0 || j < tab->n_dead ||
+ !isl_int_is_one(tab->mat->row[r][0]) ||
+ (!isl_int_is_one(tab->mat->row[r][2 + tab->M + j]) &&
+ !isl_int_is_negone(tab->mat->row[r][2 + tab->M + j]))) {
+ if (isl_tab_rollback(tab, snap) < 0)
+ goto error;
+ continue;
+ }
+ if (isl_tab_pivot(tab, r, j) < 0)
+ goto error;
+ if (isl_tab_kill_col(tab, j) < 0)
+ goto error;
+
+ tab = restore_lexmin(tab);
+ }
+
+ isl_vec_free(eq);
+
+ return;
+error:
+ isl_vec_free(eq);
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static int context_gbr_detect_equalities(struct isl_context *context,
+ struct isl_tab *tab)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ struct isl_ctx *ctx;
+ int i;
+ enum isl_lp_result res;
+ unsigned n_ineq;
+
+ ctx = cgbr->tab->mat->ctx;
+
+ if (!cgbr->cone) {
+ struct isl_basic_set *bset = isl_tab_peek_bset(cgbr->tab);
+ cgbr->cone = isl_tab_from_recession_cone(bset, 0);
+ if (!cgbr->cone)
+ goto error;
+ if (isl_tab_track_bset(cgbr->cone, isl_basic_set_dup(bset)) < 0)
+ goto error;
+ }
+ if (isl_tab_detect_implicit_equalities(cgbr->cone) < 0)
+ goto error;
+
+ n_ineq = cgbr->tab->bmap->n_ineq;
+ cgbr->tab = isl_tab_detect_equalities(cgbr->tab, cgbr->cone);
+ if (cgbr->tab && cgbr->tab->bmap->n_ineq > n_ineq)
+ propagate_equalities(cgbr, tab, n_ineq);
+
+ return 0;
+error:
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+ return -1;
+}
+
+static int context_gbr_get_div(struct isl_context *context, struct isl_tab *tab,
+ struct isl_vec *div)
+{
+ return get_div(tab, context, div);
+}
+
+static int context_gbr_add_div(struct isl_context *context, struct isl_vec *div)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ if (cgbr->cone) {
+ int k;
+
+ if (isl_tab_extend_cons(cgbr->cone, 3) < 0)
+ return -1;
+ if (isl_tab_extend_vars(cgbr->cone, 1) < 0)
+ return -1;
+ if (isl_tab_allocate_var(cgbr->cone) <0)
+ return -1;
+
+ cgbr->cone->bmap = isl_basic_map_extend_dim(cgbr->cone->bmap,
+ isl_basic_map_get_dim(cgbr->cone->bmap), 1, 0, 2);
+ k = isl_basic_map_alloc_div(cgbr->cone->bmap);
+ if (k < 0)
+ return -1;
+ isl_seq_cpy(cgbr->cone->bmap->div[k], div->el, div->size);
+ if (isl_tab_push(cgbr->cone, isl_tab_undo_bmap_div) < 0)
+ return -1;
+ }
+ return context_tab_add_div(cgbr->tab, div,
+ context_gbr_add_ineq_wrap, context);
+}
+
+static int context_gbr_best_split(struct isl_context *context,
+ struct isl_tab *tab)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ struct isl_tab_undo *snap;
+ int r;
+
+ snap = isl_tab_snap(cgbr->tab);
+ r = best_split(tab, cgbr->tab);
+
+ if (isl_tab_rollback(cgbr->tab, snap) < 0)
+ return -1;
+
+ return r;
+}
+
+static int context_gbr_is_empty(struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ if (!cgbr->tab)
+ return -1;
+ return cgbr->tab->empty;
+}
+
+struct isl_gbr_tab_undo {
+ struct isl_tab_undo *tab_snap;
+ struct isl_tab_undo *shifted_snap;
+ struct isl_tab_undo *cone_snap;
+};
+
+static void *context_gbr_save(struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ struct isl_gbr_tab_undo *snap;
+
+ snap = isl_alloc_type(cgbr->tab->mat->ctx, struct isl_gbr_tab_undo);
+ if (!snap)
+ return NULL;
+
+ snap->tab_snap = isl_tab_snap(cgbr->tab);
+ if (isl_tab_save_samples(cgbr->tab) < 0)
+ goto error;
+
+ if (cgbr->shifted)
+ snap->shifted_snap = isl_tab_snap(cgbr->shifted);
+ else
+ snap->shifted_snap = NULL;
+
+ if (cgbr->cone)
+ snap->cone_snap = isl_tab_snap(cgbr->cone);
+ else
+ snap->cone_snap = NULL;
+
+ return snap;
+error:
+ free(snap);
+ return NULL;
+}
+
+static void context_gbr_restore(struct isl_context *context, void *save)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ struct isl_gbr_tab_undo *snap = (struct isl_gbr_tab_undo *)save;
+ if (!snap)
+ goto error;
+ if (isl_tab_rollback(cgbr->tab, snap->tab_snap) < 0) {
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+ }
+
+ if (snap->shifted_snap) {
+ if (isl_tab_rollback(cgbr->shifted, snap->shifted_snap) < 0)
+ goto error;
+ } else if (cgbr->shifted) {
+ isl_tab_free(cgbr->shifted);
+ cgbr->shifted = NULL;
+ }
+
+ if (snap->cone_snap) {
+ if (isl_tab_rollback(cgbr->cone, snap->cone_snap) < 0)
+ goto error;
+ } else if (cgbr->cone) {
+ isl_tab_free(cgbr->cone);
+ cgbr->cone = NULL;
+ }
+
+ free(snap);
+
+ return;
+error:
+ free(snap);
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static int context_gbr_is_ok(struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ return !!cgbr->tab;
+}
+
+static void context_gbr_invalidate(struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ isl_tab_free(cgbr->tab);
+ cgbr->tab = NULL;
+}
+
+static void context_gbr_free(struct isl_context *context)
+{
+ struct isl_context_gbr *cgbr = (struct isl_context_gbr *)context;
+ isl_tab_free(cgbr->tab);
+ isl_tab_free(cgbr->shifted);
+ isl_tab_free(cgbr->cone);
+ free(cgbr);
+}
+
+struct isl_context_op isl_context_gbr_op = {
+ context_gbr_detect_nonnegative_parameters,
+ context_gbr_peek_basic_set,
+ context_gbr_peek_tab,
+ context_gbr_add_eq,
+ context_gbr_add_ineq,
+ context_gbr_ineq_sign,
+ context_gbr_test_ineq,
+ context_gbr_get_div,
+ context_gbr_add_div,
+ context_gbr_detect_equalities,
+ context_gbr_best_split,
+ context_gbr_is_empty,
+ context_gbr_is_ok,
+ context_gbr_save,
+ context_gbr_restore,
+ context_gbr_invalidate,
+ context_gbr_free,
+};
+
+static struct isl_context *isl_context_gbr_alloc(struct isl_basic_set *dom)
+{
+ struct isl_context_gbr *cgbr;
+
+ if (!dom)
+ return NULL;
+
+ cgbr = isl_calloc_type(dom->ctx, struct isl_context_gbr);
+ if (!cgbr)
+ return NULL;
+
+ cgbr->context.op = &isl_context_gbr_op;
+
+ cgbr->shifted = NULL;
+ cgbr->cone = NULL;
+ cgbr->tab = isl_tab_from_basic_set(dom);
+ cgbr->tab = isl_tab_init_samples(cgbr->tab);
+ if (!cgbr->tab)
+ goto error;
+ if (isl_tab_track_bset(cgbr->tab,
+ isl_basic_set_cow(isl_basic_set_copy(dom))) < 0)
+ goto error;
+ check_gbr_integer_feasible(cgbr);
+
+ return &cgbr->context;
error:
- isl_basic_set_free(bset);
+ cgbr->context.op->free(&cgbr->context);
return NULL;
}
+static struct isl_context *isl_context_alloc(struct isl_basic_set *dom)
+{
+ if (!dom)
+ return NULL;
+
+ if (dom->ctx->opt->context == ISL_CONTEXT_LEXMIN)
+ return isl_context_lex_alloc(dom);
+ else
+ return isl_context_gbr_alloc(dom);
+}
+
/* Construct an isl_sol_map structure for accumulating the solution.
* If track_empty is set, then we also keep track of the parts
* of the context where there is no solution.
static struct isl_sol_map *sol_map_init(struct isl_basic_map *bmap,
struct isl_basic_set *dom, int track_empty, int max)
{
- struct isl_sol_map *sol_map;
- struct isl_tab *context_tab;
- int f;
+ struct isl_sol_map *sol_map = NULL;
- sol_map = isl_calloc_type(bset->ctx, struct isl_sol_map);
+ if (!bmap)
+ goto error;
+
+ sol_map = isl_calloc_type(bmap->ctx, struct isl_sol_map);
if (!sol_map)
goto error;
- sol_map->max = max;
+ sol_map->sol.rational = ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL);
+ sol_map->sol.dec_level.callback.run = &sol_dec_level_wrap;
+ sol_map->sol.dec_level.sol = &sol_map->sol;
+ sol_map->sol.max = max;
+ sol_map->sol.n_out = isl_basic_map_dim(bmap, isl_dim_out);
sol_map->sol.add = &sol_map_add_wrap;
+ sol_map->sol.add_empty = track_empty ? &sol_map_add_empty_wrap : NULL;
sol_map->sol.free = &sol_map_free_wrap;
sol_map->map = isl_map_alloc_dim(isl_basic_map_get_dim(bmap), 1,
ISL_MAP_DISJOINT);
if (!sol_map->map)
goto error;
- context_tab = context_tab_for_lexmin(isl_basic_set_copy(dom));
- context_tab = restore_lexmin(context_tab);
- sol_map->sol.context_tab = context_tab;
- f = context_is_feasible(&sol_map->sol);
- if (f < 0)
+ sol_map->sol.context = isl_context_alloc(dom);
+ if (!sol_map->sol.context)
goto error;
if (track_empty) {
return NULL;
}
-/* For each variable in the context tableau, check if the variable can
- * only attain non-negative values. If so, mark the parameter as non-negative
- * in the main tableau. This allows for a more direct identification of some
- * cases of violated constraints.
- */
-static struct isl_tab *tab_detect_nonnegative_parameters(struct isl_tab *tab,
- struct isl_tab *context_tab)
-{
- int i;
- struct isl_tab_undo *snap, *snap2;
- struct isl_vec *ineq = NULL;
- struct isl_tab_var *var;
- int n;
-
- if (context_tab->n_var == 0)
- return tab;
-
- ineq = isl_vec_alloc(tab->mat->ctx, 1 + context_tab->n_var);
- if (!ineq)
- goto error;
-
- if (isl_tab_extend_cons(context_tab, 1) < 0)
- goto error;
-
- snap = isl_tab_snap(context_tab);
- isl_tab_push_basis(context_tab);
-
- snap2 = isl_tab_snap(context_tab);
-
- n = 0;
- isl_seq_clr(ineq->el, ineq->size);
- for (i = 0; i < context_tab->n_var; ++i) {
- isl_int_set_si(ineq->el[1 + i], 1);
- context_tab = isl_tab_add_ineq(context_tab, ineq->el);
- var = &context_tab->con[context_tab->n_con - 1];
- if (!context_tab->empty &&
- !isl_tab_min_at_most_neg_one(context_tab, var)) {
- int j = i;
- if (i >= tab->n_param)
- j = i - tab->n_param + tab->n_var - tab->n_div;
- tab->var[j].is_nonneg = 1;
- n++;
- }
- isl_int_set_si(ineq->el[1 + i], 0);
- if (isl_tab_rollback(context_tab, snap2) < 0)
- goto error;
- }
-
- if (isl_tab_rollback(context_tab, snap) < 0)
- goto error;
-
- if (n == context_tab->n_var) {
- context_tab->mat = isl_mat_drop_cols(context_tab->mat, 2, 1);
- context_tab->M = 0;
- }
-
- isl_vec_free(ineq);
- return tab;
-error:
- isl_vec_free(ineq);
- isl_tab_free(tab);
- return NULL;
-}
-
/* Check whether all coefficients of (non-parameter) variables
* are non-positive, meaning that no pivots can be performed on the row.
*/
* >=0 ? Y N
* any neg
*/
-static int row_sign(struct isl_tab *tab, struct isl_sol *sol, int row)
+static enum isl_tab_row_sign row_sign(struct isl_tab *tab,
+ struct isl_sol *sol, int row)
{
- int i;
- struct isl_tab_undo *snap = NULL;
struct isl_vec *ineq = NULL;
- int res = isl_tab_row_unknown;
+ enum isl_tab_row_sign res = isl_tab_row_unknown;
int critical;
int strict;
- int sgn;
int row2;
- isl_int tmp;
- struct isl_tab *context_tab = sol->context_tab;
if (tab->row_sign[row] != isl_tab_row_unknown)
return tab->row_sign[row];
critical = is_critical(tab, row);
- isl_assert(tab->mat->ctx, context_tab->samples, goto error);
- isl_assert(tab->mat->ctx, context_tab->samples->n_col == 1 + context_tab->n_var, goto error);
-
ineq = get_row_parameter_ineq(tab, row);
if (!ineq)
goto error;
strict = is_strict(ineq);
- isl_int_init(tmp);
- for (i = context_tab->n_outside; i < context_tab->n_sample; ++i) {
- isl_seq_inner_product(context_tab->samples->row[i], ineq->el,
- ineq->size, &tmp);
- sgn = isl_int_sgn(tmp);
- if (sgn > 0 || (sgn == 0 && (critical || strict))) {
- if (res == isl_tab_row_unknown)
- res = isl_tab_row_pos;
- if (res == isl_tab_row_neg)
- res = isl_tab_row_any;
- }
- if (sgn < 0) {
- if (res == isl_tab_row_unknown)
- res = isl_tab_row_neg;
- if (res == isl_tab_row_pos)
- res = isl_tab_row_any;
- }
- if (res == isl_tab_row_any)
- break;
- }
- isl_int_clear(tmp);
-
- if (res != isl_tab_row_any) {
- if (isl_tab_extend_cons(context_tab, 1) < 0)
- goto error;
-
- snap = isl_tab_snap(context_tab);
- isl_tab_push_basis(context_tab);
- }
+ res = sol->context->op->ineq_sign(sol->context, ineq->el,
+ critical || strict);
if (res == isl_tab_row_unknown || res == isl_tab_row_pos) {
/* test for negative values */
isl_seq_neg(ineq->el, ineq->el, ineq->size);
isl_int_sub_ui(ineq->el[0], ineq->el[0], 1);
- isl_tab_push_basis(context_tab);
- sol->context_tab = add_lexmin_ineq(sol->context_tab, ineq->el);
- feasible = context_is_feasible(sol);
+ feasible = sol->context->op->test_ineq(sol->context, ineq->el);
if (feasible < 0)
goto error;
- context_tab = sol->context_tab;
if (!feasible)
res = isl_tab_row_pos;
else
res = (res == isl_tab_row_unknown) ? isl_tab_row_neg
: isl_tab_row_any;
- if (isl_tab_rollback(context_tab, snap) < 0)
- goto error;
-
if (res == isl_tab_row_neg) {
isl_seq_neg(ineq->el, ineq->el, ineq->size);
isl_int_sub_ui(ineq->el[0], ineq->el[0], 1);
if (!critical && !strict)
isl_int_sub_ui(ineq->el[0], ineq->el[0], 1);
- isl_tab_push_basis(context_tab);
- sol->context_tab = add_lexmin_ineq(sol->context_tab, ineq->el);
- feasible = context_is_feasible(sol);
+ feasible = sol->context->op->test_ineq(sol->context, ineq->el);
if (feasible < 0)
goto error;
- context_tab = sol->context_tab;
if (feasible)
res = isl_tab_row_any;
- if (isl_tab_rollback(context_tab, snap) < 0)
- goto error;
}
isl_vec_free(ineq);
return res;
error:
isl_vec_free(ineq);
- return 0;
+ return isl_tab_row_unknown;
}
-static struct isl_sol *find_solutions(struct isl_sol *sol, struct isl_tab *tab);
+static void find_solutions(struct isl_sol *sol, struct isl_tab *tab);
/* Find solutions for values of the parameters that satisfy the given
* inequality.
* and that we need to do this before saving the current basis
* such that the basis has been restore before we restore the row signs.
*/
-static struct isl_sol *find_in_pos(struct isl_sol *sol,
- struct isl_tab *tab, isl_int *ineq)
+static void find_in_pos(struct isl_sol *sol, struct isl_tab *tab, isl_int *ineq)
{
- struct isl_tab_undo *snap;
+ void *saved;
- snap = isl_tab_snap(sol->context_tab);
- isl_tab_push_basis(sol->context_tab);
- if (isl_tab_extend_cons(sol->context_tab, 1) < 0)
+ if (!sol->context)
goto error;
+ saved = sol->context->op->save(sol->context);
tab = isl_tab_dup(tab);
if (!tab)
goto error;
- sol->context_tab = add_lexmin_ineq(sol->context_tab, ineq);
- sol->context_tab = check_samples(sol->context_tab, ineq, 0);
+ sol->context->op->add_ineq(sol->context, ineq, 0, 1);
- sol = find_solutions(sol, tab);
+ find_solutions(sol, tab);
- isl_tab_rollback(sol->context_tab, snap);
- return sol;
+ sol->context->op->restore(sol->context, saved);
+ return;
error:
- isl_tab_rollback(sol->context_tab, snap);
- sol_free(sol);
- return NULL;
+ sol->error = 1;
}
/* Record the absence of solutions for those values of the parameters
* that do not satisfy the given inequality with equality.
*/
-static struct isl_sol *no_sol_in_strict(struct isl_sol *sol,
+static void no_sol_in_strict(struct isl_sol *sol,
struct isl_tab *tab, struct isl_vec *ineq)
{
int empty;
- int f;
- struct isl_tab_undo *snap;
- snap = isl_tab_snap(sol->context_tab);
- isl_tab_push_basis(sol->context_tab);
- if (isl_tab_extend_cons(sol->context_tab, 1) < 0)
+ void *saved;
+
+ if (!sol->context)
goto error;
+ saved = sol->context->op->save(sol->context);
isl_int_sub_ui(ineq->el[0], ineq->el[0], 1);
- sol->context_tab = add_lexmin_ineq(sol->context_tab, ineq->el);
- f = context_valid_sample_or_feasible(sol, ineq->el, 0);
- if (f < 0)
+ sol->context->op->add_ineq(sol->context, ineq->el, 1, 0);
+ if (!sol->context)
goto error;
empty = tab->empty;
tab->empty = 1;
- sol = sol->add(sol, tab);
+ sol_add(sol, tab);
tab->empty = empty;
isl_int_add_ui(ineq->el[0], ineq->el[0], 1);
- if (isl_tab_rollback(sol->context_tab, snap) < 0)
- goto error;
- return sol;
+ sol->context->op->restore(sol->context, saved);
+ return;
error:
- sol_free(sol);
- return NULL;
-}
-
-/* Given a main tableau where more than one row requires a split,
- * determine and return the "best" row to split on.
- *
- * Given two rows in the main tableau, if the inequality corresponding
- * to the first row is redundant with respect to that of the second row
- * in the current tableau, then it is better to split on the second row,
- * since in the positive part, both row will be positive.
- * (In the negative part a pivot will have to be performed and just about
- * anything can happen to the sign of the other row.)
- *
- * As a simple heuristic, we therefore select the row that makes the most
- * of the other rows redundant.
- *
- * Perhaps it would also be useful to look at the number of constraints
- * that conflict with any given constraint.
- */
-static int best_split(struct isl_tab *tab, struct isl_tab *context_tab)
-{
- struct isl_tab_undo *snap, *snap2;
- int split;
- int row;
- int best = -1;
- int best_r;
-
- if (isl_tab_extend_cons(context_tab, 2) < 0)
- return -1;
-
- snap = isl_tab_snap(context_tab);
- isl_tab_push_basis(context_tab);
- snap2 = isl_tab_snap(context_tab);
-
- for (split = tab->n_redundant; split < tab->n_row; ++split) {
- struct isl_tab_undo *snap3;
- struct isl_vec *ineq = NULL;
- int r = 0;
-
- if (!isl_tab_var_from_row(tab, split)->is_nonneg)
- continue;
- if (tab->row_sign[split] != isl_tab_row_any)
- continue;
-
- ineq = get_row_parameter_ineq(tab, split);
- if (!ineq)
- return -1;
- context_tab = isl_tab_add_ineq(context_tab, ineq->el);
- isl_vec_free(ineq);
-
- snap3 = isl_tab_snap(context_tab);
-
- for (row = tab->n_redundant; row < tab->n_row; ++row) {
- struct isl_tab_var *var;
-
- if (row == split)
- continue;
- if (!isl_tab_var_from_row(tab, row)->is_nonneg)
- continue;
- if (tab->row_sign[row] != isl_tab_row_any)
- continue;
-
- ineq = get_row_parameter_ineq(tab, row);
- if (!ineq)
- return -1;
- context_tab = isl_tab_add_ineq(context_tab, ineq->el);
- isl_vec_free(ineq);
- var = &context_tab->con[context_tab->n_con - 1];
- if (!context_tab->empty &&
- !isl_tab_min_at_most_neg_one(context_tab, var))
- r++;
- if (isl_tab_rollback(context_tab, snap3) < 0)
- return -1;
- }
- if (best == -1 || r > best_r) {
- best = split;
- best_r = r;
- }
- if (isl_tab_rollback(context_tab, snap2) < 0)
- return -1;
- }
-
- if (isl_tab_rollback(context_tab, snap) < 0)
- return -1;
-
- return best;
+ sol->error = 1;
}
/* Compute the lexicographic minimum of the set represented by the main
* In the part of the context where this inequality does not hold, the
* main tableau is marked as being empty.
*/
-static struct isl_sol *find_solutions(struct isl_sol *sol, struct isl_tab *tab)
+static void find_solutions(struct isl_sol *sol, struct isl_tab *tab)
{
- struct isl_tab **context_tab;
+ struct isl_context *context;
- if (!tab || !sol)
+ if (!tab || sol->error)
goto error;
- context_tab = &sol->context_tab;
+ context = sol->context;
if (tab->empty)
goto done;
- if ((*context_tab)->empty)
+ if (context->op->is_empty(context))
goto done;
for (; tab && !tab->empty; tab = restore_lexmin(tab)) {
int flags;
int row;
- int sgn;
+ enum isl_tab_row_sign sgn;
int split = -1;
int n_split = 0;
if (split != -1) {
struct isl_vec *ineq;
if (n_split != 1)
- split = best_split(tab, *context_tab);
+ split = context->op->best_split(context, tab);
if (split < 0)
goto error;
ineq = get_row_parameter_ineq(tab, split);
tab->row_sign[row] = isl_tab_row_unknown;
}
tab->row_sign[split] = isl_tab_row_pos;
- sol = find_in_pos(sol, tab, ineq->el);
+ sol_inc_level(sol);
+ find_in_pos(sol, tab, ineq->el);
tab->row_sign[split] = isl_tab_row_neg;
row = split;
isl_seq_neg(ineq->el, ineq->el, ineq->size);
isl_int_sub_ui(ineq->el[0], ineq->el[0], 1);
- *context_tab = add_lexmin_ineq(*context_tab, ineq->el);
- *context_tab = check_samples(*context_tab, ineq->el, 0);
+ context->op->add_ineq(context, ineq->el, 0, 1);
isl_vec_free(ineq);
- if (!sol)
+ if (sol->error)
goto error;
continue;
}
if (tab->rational)
break;
- row = first_non_integer(tab, &flags);
+ row = first_non_integer_row(tab, &flags);
if (row < 0)
break;
if (ISL_FL_ISSET(flags, I_PAR)) {
if (ISL_FL_ISSET(flags, I_VAR)) {
- tab = isl_tab_mark_empty(tab);
+ if (isl_tab_mark_empty(tab) < 0)
+ goto error;
break;
}
row = add_cut(tab, row);
struct isl_vec *div;
struct isl_vec *ineq;
int d;
- if (isl_tab_extend_cons(*context_tab, 3) < 0)
- goto error;
div = get_row_split_div(tab, row);
if (!div)
goto error;
- d = get_div(tab, context_tab, div);
+ d = context->op->get_div(context, tab, div);
isl_vec_free(div);
if (d < 0)
goto error;
- ineq = ineq_for_div((*context_tab)->bset, d);
- sol = no_sol_in_strict(sol, tab, ineq);
+ ineq = ineq_for_div(context->op->peek_basic_set(context), d);
+ sol_inc_level(sol);
+ no_sol_in_strict(sol, tab, ineq);
isl_seq_neg(ineq->el, ineq->el, ineq->size);
- *context_tab = add_lexmin_ineq(*context_tab, ineq->el);
- *context_tab = check_samples(*context_tab, ineq->el, 0);
+ context->op->add_ineq(context, ineq->el, 1, 1);
isl_vec_free(ineq);
- if (!sol)
+ if (sol->error || !context->op->is_ok(context))
goto error;
tab = set_row_cst_to_div(tab, row, d);
+ if (context->op->is_empty(context))
+ break;
} else
- row = add_parametric_cut(tab, row, context_tab);
+ row = add_parametric_cut(tab, row, context);
if (row < 0)
goto error;
}
done:
- sol = sol->add(sol, tab);
+ sol_add(sol, tab);
isl_tab_free(tab);
- return sol;
+ return;
error:
isl_tab_free(tab);
sol_free(sol);
- return NULL;
}
/* Compute the lexicographic minimum of the set represented by the main
* In parts of the context where the added equality does not hold,
* the main tableau is marked as being empty.
*/
-static struct isl_sol *find_solutions_main(struct isl_sol *sol,
- struct isl_tab *tab)
+static void find_solutions_main(struct isl_sol *sol, struct isl_tab *tab)
{
int row;
+ sol->level = 0;
+
for (row = tab->n_redundant; row < tab->n_row; ++row) {
int p;
struct isl_vec *eq;
p = tab->row_var[row]
+ tab->n_param - (tab->n_var - tab->n_div);
- if (isl_tab_extend_cons(sol->context_tab, 2) < 0)
- goto error;
-
eq = isl_vec_alloc(tab->mat->ctx, 1+tab->n_param+tab->n_div);
get_row_parameter_line(tab, row, eq->el);
isl_int_neg(eq->el[1 + p], tab->mat->row[row][0]);
eq = isl_vec_normalize(eq);
- sol = no_sol_in_strict(sol, tab, eq);
+ sol_inc_level(sol);
+ no_sol_in_strict(sol, tab, eq);
isl_seq_neg(eq->el, eq->el, eq->size);
- sol = no_sol_in_strict(sol, tab, eq);
+ sol_inc_level(sol);
+ no_sol_in_strict(sol, tab, eq);
isl_seq_neg(eq->el, eq->el, eq->size);
- sol->context_tab = add_lexmin_eq(sol->context_tab, eq->el);
- context_valid_sample_or_feasible(sol, eq->el, 1);
- sol->context_tab = check_samples(sol->context_tab, eq->el, 1);
+ sol->context->op->add_eq(sol->context, eq->el, 1, 1);
isl_vec_free(eq);
- isl_tab_mark_redundant(tab, row);
-
- if (!sol->context_tab)
+ if (isl_tab_mark_redundant(tab, row) < 0)
goto error;
- if (sol->context_tab->empty)
+
+ if (sol->context->op->is_empty(sol->context))
break;
row = tab->n_redundant - 1;
}
- return find_solutions(sol, tab);
+ find_solutions(sol, tab);
+
+ sol->level = 0;
+ sol_pop(sol);
+
+ return;
error:
isl_tab_free(tab);
sol_free(sol);
- return NULL;
}
-static struct isl_sol_map *sol_map_find_solutions(struct isl_sol_map *sol_map,
+static void sol_map_find_solutions(struct isl_sol_map *sol_map,
struct isl_tab *tab)
{
- return (struct isl_sol_map *)find_solutions_main(&sol_map->sol, tab);
+ find_solutions_main(&sol_map->sol, tab);
}
/* Check if integer division "div" of "dom" also occurs in "bmap".
struct isl_tab *tab;
struct isl_map *result = NULL;
struct isl_sol_map *sol_map = NULL;
+ struct isl_context *context;
+ struct isl_basic_map *eq;
if (empty)
*empty = NULL;
isl_assert(bmap->ctx,
isl_basic_map_compatible_domain(bmap, dom), goto error);
- bmap = isl_basic_map_detect_equalities(bmap);
+ eq = isl_basic_map_copy(bmap);
+ eq = isl_basic_map_intersect_domain(eq, isl_basic_set_copy(dom));
+ eq = isl_basic_map_affine_hull(eq);
+ bmap = isl_basic_map_intersect(bmap, eq);
if (dom->n_div) {
dom = isl_basic_set_order_divs(dom);
if (!sol_map)
goto error;
- if (isl_basic_set_fast_is_empty(sol_map->sol.context_tab->bset))
+ context = sol_map->sol.context;
+ if (isl_basic_set_fast_is_empty(context->op->peek_basic_set(context)))
/* nothing */;
else if (isl_basic_map_fast_is_empty(bmap))
- sol_map = add_empty(sol_map);
+ sol_map_add_empty_if_needed(sol_map,
+ isl_basic_set_copy(context->op->peek_basic_set(context)));
else {
tab = tab_for_lexmin(bmap,
- sol_map->sol.context_tab->bset, 1, max);
- tab = tab_detect_nonnegative_parameters(tab,
- sol_map->sol.context_tab);
- sol_map = sol_map_find_solutions(sol_map, tab);
- if (!sol_map)
- goto error;
+ context->op->peek_basic_set(context), 1, max);
+ tab = context->op->detect_nonnegative_parameters(context, tab);
+ sol_map_find_solutions(sol_map, tab);
}
+ if (sol_map->sol.error)
+ goto error;
result = isl_map_copy(sol_map->map);
if (empty)
*empty = isl_set_copy(sol_map->empty);
- sol_map_free(sol_map);
+ sol_free(&sol_map->sol);
isl_basic_map_free(bmap);
return result;
error:
- sol_map_free(sol_map);
+ sol_free(&sol_map->sol);
isl_basic_map_free(bmap);
return NULL;
}
int (*fn)(__isl_take isl_basic_set *dom,
__isl_take isl_mat *map, void *user);
void *user;
- int max;
};
static void sol_for_free(struct isl_sol_for *sol_for)
{
- isl_tab_free(sol_for->sol.context_tab);
+ if (sol_for->sol.context)
+ sol_for->sol.context->op->free(sol_for->sol.context);
free(sol_for);
}
/* Add the solution identified by the tableau and the context tableau.
*
- * See documentation of sol_map_add for more details.
+ * See documentation of sol_add for more details.
*
* Instead of constructing a basic map, this function calls a user
* defined function with the current context as a basic set and
* may refer to the divs, the basic set is not simplified.
* (Simplification may reorder or remove divs.)
*/
-static struct isl_sol_for *sol_for_add(struct isl_sol_for *sol,
- struct isl_tab *tab)
+static void sol_for_add(struct isl_sol_for *sol,
+ struct isl_basic_set *dom, struct isl_mat *M)
{
- struct isl_tab *context_tab;
- struct isl_basic_set *bset;
- struct isl_mat *mat = NULL;
- unsigned n_out;
- unsigned off;
- int row, i;
-
- if (!sol || !tab)
- goto error;
-
- if (tab->empty)
- return sol;
-
- off = 2 + tab->M;
- context_tab = sol->sol.context_tab;
-
- n_out = tab->n_var - tab->n_param - tab->n_div;
- mat = isl_mat_alloc(tab->mat->ctx, 1 + n_out, 1 + tab->n_param + tab->n_div);
- if (!mat)
+ if (sol->sol.error || !dom || !M)
goto error;
- isl_seq_clr(mat->row[0] + 1, mat->n_col - 1);
- isl_int_set_si(mat->row[0][0], 1);
- for (row = 0; row < n_out; ++row) {
- int i = tab->n_param + row;
- int r, j;
-
- isl_seq_clr(mat->row[1 + row], mat->n_col);
- if (!tab->var[i].is_row)
- continue;
-
- r = tab->var[i].index;
- /* no unbounded */
- if (tab->M)
- isl_assert(mat->ctx, isl_int_eq(tab->mat->row[r][2],
- tab->mat->row[r][0]),
- goto error);
- isl_int_set(mat->row[1 + row][0], tab->mat->row[r][1]);
- for (j = 0; j < tab->n_param; ++j) {
- int col;
- if (tab->var[j].is_row)
- continue;
- col = tab->var[j].index;
- isl_int_set(mat->row[1 + row][1 + j],
- tab->mat->row[r][off + col]);
- }
- for (j = 0; j < tab->n_div; ++j) {
- int col;
- if (tab->var[tab->n_var - tab->n_div+j].is_row)
- continue;
- col = tab->var[tab->n_var - tab->n_div+j].index;
- isl_int_set(mat->row[1 + row][1 + tab->n_param + j],
- tab->mat->row[r][off + col]);
- }
- if (!isl_int_is_one(tab->mat->row[r][0]))
- isl_seq_scale_down(mat->row[1 + row], mat->row[1 + row],
- tab->mat->row[r][0], mat->n_col);
- if (sol->max)
- isl_seq_neg(mat->row[1 + row], mat->row[1 + row],
- mat->n_col);
- }
-
- bset = isl_basic_set_dup(context_tab->bset);
- bset = isl_basic_set_finalize(bset);
+ dom = isl_basic_set_simplify(dom);
+ dom = isl_basic_set_finalize(dom);
- if (sol->fn(bset, isl_mat_copy(mat), sol->user) < 0)
+ if (sol->fn(isl_basic_set_copy(dom), isl_mat_copy(M), sol->user) < 0)
goto error;
- isl_mat_free(mat);
- return sol;
+ isl_basic_set_free(dom);
+ isl_mat_free(M);
+ return;
error:
- isl_mat_free(mat);
- sol_free(&sol->sol);
- return NULL;
+ isl_basic_set_free(dom);
+ isl_mat_free(M);
+ sol->sol.error = 1;
}
-static struct isl_sol *sol_for_add_wrap(struct isl_sol *sol,
- struct isl_tab *tab)
+static void sol_for_add_wrap(struct isl_sol *sol,
+ struct isl_basic_set *dom, struct isl_mat *M)
{
- return (struct isl_sol *)sol_for_add((struct isl_sol_for *)sol, tab);
+ sol_for_add((struct isl_sol_for *)sol, dom, M);
}
static struct isl_sol_for *sol_for_init(struct isl_basic_map *bmap, int max,
struct isl_sol_for *sol_for = NULL;
struct isl_dim *dom_dim;
struct isl_basic_set *dom = NULL;
- struct isl_tab *context_tab;
- int f;
- sol_for = isl_calloc_type(bset->ctx, struct isl_sol_for);
+ sol_for = isl_calloc_type(bmap->ctx, struct isl_sol_for);
if (!sol_for)
goto error;
dom_dim = isl_dim_domain(isl_dim_copy(bmap->dim));
dom = isl_basic_set_universe(dom_dim);
+ sol_for->sol.rational = ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL);
+ sol_for->sol.dec_level.callback.run = &sol_dec_level_wrap;
+ sol_for->sol.dec_level.sol = &sol_for->sol;
sol_for->fn = fn;
sol_for->user = user;
- sol_for->max = max;
+ sol_for->sol.max = max;
+ sol_for->sol.n_out = isl_basic_map_dim(bmap, isl_dim_out);
sol_for->sol.add = &sol_for_add_wrap;
+ sol_for->sol.add_empty = NULL;
sol_for->sol.free = &sol_for_free_wrap;
- context_tab = context_tab_for_lexmin(isl_basic_set_copy(dom));
- context_tab = restore_lexmin(context_tab);
- sol_for->sol.context_tab = context_tab;
- f = context_is_feasible(&sol_for->sol);
- if (f < 0)
+ sol_for->sol.context = isl_context_alloc(dom);
+ if (!sol_for->sol.context)
goto error;
isl_basic_set_free(dom);
return NULL;
}
-static struct isl_sol_for *sol_for_find_solutions(struct isl_sol_for *sol_for,
+static void sol_for_find_solutions(struct isl_sol_for *sol_for,
struct isl_tab *tab)
{
- return (struct isl_sol_for *)find_solutions_main(&sol_for->sol, tab);
+ find_solutions_main(&sol_for->sol, tab);
}
int isl_basic_map_foreach_lexopt(__isl_keep isl_basic_map *bmap, int max,
/* nothing */;
else {
struct isl_tab *tab;
+ struct isl_context *context = sol_for->sol.context;
tab = tab_for_lexmin(bmap,
- sol_for->sol.context_tab->bset, 1, max);
- tab = tab_detect_nonnegative_parameters(tab,
- sol_for->sol.context_tab);
- sol_for = sol_for_find_solutions(sol_for, tab);
- if (!sol_for)
+ context->op->peek_basic_set(context), 1, max);
+ tab = context->op->detect_nonnegative_parameters(context, tab);
+ sol_for_find_solutions(sol_for, tab);
+ if (sol_for->sol.error)
goto error;
}
- sol_for_free(sol_for);
+ sol_free(&sol_for->sol);
isl_basic_map_free(bmap);
return 0;
error:
- sol_for_free(sol_for);
+ sol_free(&sol_for->sol);
isl_basic_map_free(bmap);
return -1;
}
projects / platform / upstream / isl.git / blobdiff