#include "isl_lp.h"
#include "isl_map.h"
#include "isl_mat.h"
+#include "isl_set.h"
struct isl_tab_var {
int index;
unsigned is_redundant : 1;
unsigned marked : 1;
unsigned frozen : 1;
+ unsigned negated : 1;
};
enum isl_tab_undo_type {
isl_tab_undo_zero,
isl_tab_undo_allocate,
isl_tab_undo_relax,
+ isl_tab_undo_bset_ineq,
+ isl_tab_undo_bset_eq,
+ isl_tab_undo_bset_div,
isl_tab_undo_saved_basis,
+ isl_tab_undo_drop_sample,
};
union isl_tab_undo_val {
* Each row expresses the corresponding row variable as an affine expression
* of the column variables.
* The first two columns in the matrix contain the common denominator of
- * the row and the numerator of the constant term. The third column
+ * the row and the numerator of the constant term.
+ * If "M" is set, then the third column represents the "big parameter".
+ * The third (M = 0) or fourth (M = 1) column
* in the matrix is called column 0 with respect to the col_var array.
* The sample value of the tableau is the value that assigns zero
* to all the column variables and the constant term of each affine
* value satisfies the non-negativity constraints (usually on the slack
* variables).
*
+ * The big parameter represents an arbitrarily big (and divisible)
+ * positive number. If present, then the sign of a row is determined
+ * lexicographically, with the sign of the big parameter coefficient
+ * considered first. The big parameter is only used while
+ * solving PILP problems.
+ *
* The first n_dead column variables have their values fixed to zero.
* The corresponding tab_vars are flagged "is_zero".
* Some of the rows that have have zero coefficients in all but
* There are "n_var" variables in total. The first "n_param" of these
* are called parameters and the last "n_div" of these are called divs.
* The basic tableau operations makes no distinction between different
- * kinds of variables.
+ * kinds of variables. These special variables are only used while
+ * solving PILP problems.
*
* Dead columns and redundant rows are detected on the fly.
* However, the basic operations do not ensure that all dead columns
* or all redundant rows are detected.
* isl_tab_detect_equalities and isl_tab_detect_redundant can be used
* to perform and exhaustive search for dead columns and redundant rows.
+ *
+ * The samples matrix contains "n_sample" integer points that have at some
+ * point been elements satisfying the tableau. The first "n_outside"
+ * of them no longer satisfy the tableau. They are kept because they
+ * can be reinstated during rollback when the constraint that cut them
+ * out is removed. These samples are only maintained for the context
+ * tableau while solving PILP problems.
*/
+enum isl_tab_row_sign {
+ isl_tab_row_unknown = 0,
+ isl_tab_row_pos,
+ isl_tab_row_neg,
+ isl_tab_row_any,
+};
struct isl_tab {
struct isl_mat *mat;
unsigned n_var;
unsigned n_param;
unsigned n_div;
+ unsigned max_var;
unsigned n_con;
unsigned n_eq;
unsigned max_con;
struct isl_tab_var *con;
int *row_var; /* v >= 0 -> var v; v < 0 -> con ~v */
int *col_var; /* v >= 0 -> var v; v < 0 -> con ~v */
+ enum isl_tab_row_sign *row_sign;
struct isl_tab_undo bottom;
struct isl_tab_undo *top;
struct isl_vec *dual;
+ struct isl_basic_set *bset;
+
+ unsigned n_sample;
+ unsigned n_outside;
+ struct isl_mat *samples;
unsigned need_undo : 1;
unsigned rational : 1;
unsigned empty : 1;
unsigned in_undo : 1;
+ unsigned M : 1;
};
struct isl_tab *isl_tab_alloc(struct isl_ctx *ctx,
- unsigned n_row, unsigned n_var);
+ unsigned n_row, unsigned n_var, unsigned M);
void isl_tab_free(struct isl_tab *tab);
struct isl_tab *isl_tab_from_basic_map(struct isl_basic_map *bmap);
void isl_tab_dump(struct isl_tab *tab, FILE *out, int indent);
+struct isl_map *isl_tab_basic_map_partial_lexopt(
+ struct isl_basic_map *bmap, struct isl_basic_set *dom,
+ struct isl_set **empty, int max);
+
/* private */
struct isl_tab_var *isl_tab_var_from_row(struct isl_tab *tab, int i);
struct isl_tab *isl_tab_dup(struct isl_tab *tab);
int isl_tab_extend_cons(struct isl_tab *tab, unsigned n_new);
int isl_tab_allocate_con(struct isl_tab *tab);
+int isl_tab_extend_vars(struct isl_tab *tab, unsigned n_new);
+int isl_tab_allocate_var(struct isl_tab *tab);
void isl_tab_pivot(struct isl_tab *tab, int row, int col);
int isl_tab_add_row(struct isl_tab *tab, isl_int *line);
int isl_tab_row_is_redundant(struct isl_tab *tab, int row);
int isl_tab_min_at_most_neg_one(struct isl_tab *tab, struct isl_tab_var *var);
+int isl_tab_kill_col(struct isl_tab *tab, int col);
void isl_tab_push(struct isl_tab *tab, enum isl_tab_undo_type type);
void isl_tab_push_var(struct isl_tab *tab,