+#include "isl_mat.h"
#include "isl_map_private.h"
#include "isl_tab.h"
tab->max_con = n_row;
tab->n_col = n_var;
tab->n_var = n_var;
+ tab->n_param = 0;
+ tab->n_div = 0;
tab->n_dead = 0;
tab->n_redundant = 0;
tab->need_undo = 0;
tab->top = &tab->bottom;
return tab;
error:
- isl_tab_free(ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
-static int extend_cons(struct isl_ctx *ctx, struct isl_tab *tab, unsigned n_new)
+int isl_tab_extend_cons(struct isl_tab *tab, unsigned n_new)
{
if (tab->max_con < tab->n_con + n_new) {
struct isl_tab_var *con;
- con = isl_realloc_array(ctx, tab->con,
+ con = isl_realloc_array(tab->mat->ctx, tab->con,
struct isl_tab_var, tab->max_con + n_new);
if (!con)
return -1;
if (tab->mat->n_row < tab->n_row + n_new) {
int *row_var;
- tab->mat = isl_mat_extend(ctx, tab->mat,
+ tab->mat = isl_mat_extend(tab->mat,
tab->n_row + n_new, tab->n_col);
if (!tab->mat)
return -1;
- row_var = isl_realloc_array(ctx, tab->row_var,
+ row_var = isl_realloc_array(tab->mat->ctx, tab->row_var,
int, tab->mat->n_row);
if (!row_var)
return -1;
return 0;
}
-struct isl_tab *isl_tab_extend(struct isl_ctx *ctx, struct isl_tab *tab,
- unsigned n_new)
+struct isl_tab *isl_tab_extend(struct isl_tab *tab, unsigned n_new)
{
- if (extend_cons(ctx, tab, n_new) >= 0)
+ if (isl_tab_extend_cons(tab, n_new) >= 0)
return tab;
- isl_tab_free(ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
-static void free_undo(struct isl_ctx *ctx, struct isl_tab *tab)
+static void free_undo(struct isl_tab *tab)
{
struct isl_tab_undo *undo, *next;
tab->top = undo;
}
-void isl_tab_free(struct isl_ctx *ctx, struct isl_tab *tab)
+void isl_tab_free(struct isl_tab *tab)
{
if (!tab)
return;
- free_undo(ctx, tab);
- isl_mat_free(ctx, tab->mat);
+ free_undo(tab);
+ isl_mat_free(tab->mat);
isl_vec_free(tab->dual);
free(tab->var);
free(tab->con);
free(tab);
}
-static struct isl_tab_var *var_from_index(struct isl_ctx *ctx,
- struct isl_tab *tab, int i)
+struct isl_tab *isl_tab_dup(struct isl_tab *tab)
+{
+ int i;
+ struct isl_tab *dup;
+
+ if (!tab)
+ return NULL;
+
+ dup = isl_calloc_type(tab->ctx, struct isl_tab);
+ if (!dup)
+ return NULL;
+ dup->mat = isl_mat_dup(tab->mat);
+ if (!dup->mat)
+ goto error;
+ dup->var = isl_alloc_array(tab->ctx, struct isl_tab_var, tab->n_var);
+ if (!dup->var)
+ goto error;
+ for (i = 0; i < tab->n_var; ++i)
+ dup->var[i] = tab->var[i];
+ dup->con = isl_alloc_array(tab->ctx, struct isl_tab_var, tab->max_con);
+ if (!dup->con)
+ goto error;
+ for (i = 0; i < tab->n_con; ++i)
+ dup->con[i] = tab->con[i];
+ dup->col_var = isl_alloc_array(tab->ctx, int, tab->mat->n_col);
+ if (!dup->col_var)
+ goto error;
+ for (i = 0; i < tab->n_var; ++i)
+ dup->col_var[i] = tab->col_var[i];
+ dup->row_var = isl_alloc_array(tab->ctx, int, tab->mat->n_row);
+ if (!dup->row_var)
+ goto error;
+ for (i = 0; i < tab->n_row; ++i)
+ dup->row_var[i] = tab->row_var[i];
+ dup->n_row = tab->n_row;
+ dup->n_con = tab->n_con;
+ dup->n_eq = tab->n_eq;
+ dup->max_con = tab->max_con;
+ dup->n_col = tab->n_col;
+ dup->n_var = tab->n_var;
+ dup->n_param = tab->n_param;
+ dup->n_div = tab->n_div;
+ dup->n_dead = tab->n_dead;
+ dup->n_redundant = tab->n_redundant;
+ dup->rational = tab->rational;
+ dup->empty = tab->empty;
+ dup->need_undo = 0;
+ dup->in_undo = 0;
+ dup->bottom.type = isl_tab_undo_bottom;
+ dup->bottom.next = NULL;
+ dup->top = &dup->bottom;
+ return dup;
+error:
+ isl_tab_free(dup);
+ return NULL;
+}
+
+static struct isl_tab_var *var_from_index(struct isl_tab *tab, int i)
{
if (i >= 0)
return &tab->var[i];
return &tab->con[~i];
}
-static struct isl_tab_var *var_from_row(struct isl_ctx *ctx,
- struct isl_tab *tab, int i)
+struct isl_tab_var *isl_tab_var_from_row(struct isl_tab *tab, int i)
{
- return var_from_index(ctx, tab, tab->row_var[i]);
+ return var_from_index(tab, tab->row_var[i]);
}
-static struct isl_tab_var *var_from_col(struct isl_ctx *ctx,
- struct isl_tab *tab, int i)
+static struct isl_tab_var *var_from_col(struct isl_tab *tab, int i)
{
- return var_from_index(ctx, tab, tab->col_var[i]);
+ return var_from_index(tab, tab->col_var[i]);
}
/* Check if there are any upper bounds on column variable "var",
* i.e., non-negative rows where var appears with a negative coefficient.
* Return 1 if there are no such bounds.
*/
-static int max_is_manifestly_unbounded(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int max_is_manifestly_unbounded(struct isl_tab *tab,
+ struct isl_tab_var *var)
{
int i;
for (i = tab->n_redundant; i < tab->n_row; ++i) {
if (!isl_int_is_neg(tab->mat->row[i][2 + var->index]))
continue;
- if (var_from_row(ctx, tab, i)->is_nonneg)
+ if (isl_tab_var_from_row(tab, i)->is_nonneg)
return 0;
}
return 1;
* i.e., non-negative rows where var appears with a positive coefficient.
* Return 1 if there are no such bounds.
*/
-static int min_is_manifestly_unbounded(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int min_is_manifestly_unbounded(struct isl_tab *tab,
+ struct isl_tab_var *var)
{
int i;
for (i = tab->n_redundant; i < tab->n_row; ++i) {
if (!isl_int_is_pos(tab->mat->row[i][2 + var->index]))
continue;
- if (var_from_row(ctx, tab, i)->is_nonneg)
+ if (isl_tab_var_from_row(tab, i)->is_nonneg)
return 0;
}
return 1;
* we check if -sign(a_jc) (a_j0 a_rc - a_r0 a_jc) < 0,
* where -sign(a_jc) is equal to "sgn".
*/
-static int pivot_row(struct isl_ctx *ctx, struct isl_tab *tab,
+static int pivot_row(struct isl_tab *tab,
struct isl_tab_var *var, int sgn, int c)
{
int j, r, tsgn;
for (j = tab->n_redundant; j < tab->n_row; ++j) {
if (var && j == var->index)
continue;
- if (!var_from_row(ctx, tab, j)->is_nonneg)
+ if (!isl_tab_var_from_row(tab, j)->is_nonneg)
continue;
if (sgn * isl_int_sgn(tab->mat->row[j][2 + c]) >= 0)
continue;
* to obtain the desired effect. Otherwise, x_i has to move in the
* opposite direction.
*/
-static void find_pivot(struct isl_ctx *ctx, struct isl_tab *tab,
+static void find_pivot(struct isl_tab *tab,
struct isl_tab_var *var, struct isl_tab_var *skip_var,
int sgn, int *row, int *col)
{
*row = *col = -1;
- isl_assert(ctx, var->is_row, return);
+ isl_assert(tab->mat->ctx, var->is_row, return);
tr = tab->mat->row[var->index];
c = -1;
if (isl_int_is_zero(tr[2 + j]))
continue;
if (isl_int_sgn(tr[2 + j]) != sgn &&
- var_from_col(ctx, tab, j)->is_nonneg)
+ var_from_col(tab, j)->is_nonneg)
continue;
if (c < 0 || tab->col_var[j] < tab->col_var[c])
c = j;
return;
sgn *= isl_int_sgn(tr[2 + c]);
- r = pivot_row(ctx, tab, skip_var, sgn, c);
+ r = pivot_row(tab, skip_var, sgn, c);
*row = r < 0 ? var->index : r;
*col = c;
}
* - that is the sum of a non-negative sample value and a positive
* combination of zero or more non-negative variables.
*/
-static int is_redundant(struct isl_ctx *ctx, struct isl_tab *tab, int row)
+int isl_tab_row_is_redundant(struct isl_tab *tab, int row)
{
int i;
- if (tab->row_var[row] < 0 && !var_from_row(ctx, tab, row)->is_nonneg)
+ if (tab->row_var[row] < 0 && !isl_tab_var_from_row(tab, row)->is_nonneg)
return 0;
if (isl_int_is_neg(tab->mat->row[row][1]))
continue;
if (isl_int_is_neg(tab->mat->row[row][2 + i]))
return 0;
- if (!var_from_col(ctx, tab, i)->is_nonneg)
+ if (!var_from_col(tab, i)->is_nonneg)
return 0;
}
return 1;
}
-static void swap_rows(struct isl_ctx *ctx,
- struct isl_tab *tab, int row1, int row2)
+static void swap_rows(struct isl_tab *tab, int row1, int row2)
{
int t;
t = tab->row_var[row1];
tab->row_var[row1] = tab->row_var[row2];
tab->row_var[row2] = t;
- var_from_row(ctx, tab, row1)->index = row1;
- var_from_row(ctx, tab, row2)->index = row2;
- tab->mat = isl_mat_swap_rows(ctx, tab->mat, row1, row2);
+ isl_tab_var_from_row(tab, row1)->index = row1;
+ isl_tab_var_from_row(tab, row2)->index = row2;
+ tab->mat = isl_mat_swap_rows(tab->mat, row1, row2);
}
-static void push(struct isl_ctx *ctx, struct isl_tab *tab,
- enum isl_tab_undo_type type, struct isl_tab_var *var)
+static void push_union(struct isl_tab *tab,
+ enum isl_tab_undo_type type, union isl_tab_undo_val u)
{
struct isl_tab_undo *undo;
if (!tab->need_undo)
return;
- undo = isl_alloc_type(ctx, struct isl_tab_undo);
+ undo = isl_alloc_type(tab->mat->ctx, struct isl_tab_undo);
if (!undo) {
- free_undo(ctx, tab);
+ free_undo(tab);
tab->top = NULL;
return;
}
undo->type = type;
- undo->var = var;
+ undo->u = u;
undo->next = tab->top;
tab->top = undo;
}
+void isl_tab_push_var(struct isl_tab *tab,
+ enum isl_tab_undo_type type, struct isl_tab_var *var)
+{
+ union isl_tab_undo_val u;
+ if (var->is_row)
+ u.var_index = tab->row_var[var->index];
+ else
+ u.var_index = tab->col_var[var->index];
+ push_union(tab, type, u);
+}
+
+void isl_tab_push(struct isl_tab *tab, enum isl_tab_undo_type type)
+{
+ union isl_tab_undo_val u = { 0 };
+ push_union(tab, type, u);
+}
+
+/* Push a record on the undo stack describing the current basic
+ * variables, so that the this state can be restored during rollback.
+ */
+void isl_tab_push_basis(struct isl_tab *tab)
+{
+ int i;
+ union isl_tab_undo_val u;
+
+ u.col_var = isl_alloc_array(tab->mat->ctx, int, tab->n_col);
+ if (!u.col_var) {
+ free_undo(tab);
+ tab->top = NULL;
+ return;
+ }
+ for (i = 0; i < tab->n_col; ++i)
+ u.col_var[i] = tab->col_var[i];
+ push_union(tab, isl_tab_undo_saved_basis, u);
+}
+
/* Mark row with index "row" as being redundant.
* If we may need to undo the operation or if the row represents
* a variable of the original problem, the row is kept,
* then a return value of 1 means that the row with the given
* row number may now contain a different row that hasn't been checked yet.
*/
-static int mark_redundant(struct isl_ctx *ctx,
- struct isl_tab *tab, int row)
+int isl_tab_mark_redundant(struct isl_tab *tab, int row)
{
- struct isl_tab_var *var = var_from_row(ctx, tab, row);
+ struct isl_tab_var *var = isl_tab_var_from_row(tab, row);
var->is_redundant = 1;
- isl_assert(ctx, row >= tab->n_redundant, return);
+ isl_assert(tab->mat->ctx, row >= tab->n_redundant, return);
if (tab->need_undo || tab->row_var[row] >= 0) {
- if (tab->row_var[row] >= 0) {
+ if (tab->row_var[row] >= 0 && !var->is_nonneg) {
var->is_nonneg = 1;
- push(ctx, tab, isl_tab_undo_nonneg, var);
+ isl_tab_push_var(tab, isl_tab_undo_nonneg, var);
}
if (row != tab->n_redundant)
- swap_rows(ctx, tab, row, tab->n_redundant);
- push(ctx, tab, isl_tab_undo_redundant, var);
+ swap_rows(tab, row, tab->n_redundant);
+ isl_tab_push_var(tab, isl_tab_undo_redundant, var);
tab->n_redundant++;
return 0;
} else {
if (row != tab->n_row - 1)
- swap_rows(ctx, tab, row, tab->n_row - 1);
- var_from_row(ctx, tab, tab->n_row - 1)->index = -1;
+ swap_rows(tab, row, tab->n_row - 1);
+ isl_tab_var_from_row(tab, tab->n_row - 1)->index = -1;
tab->n_row--;
return 1;
}
}
-static void mark_empty(struct isl_ctx *ctx, struct isl_tab *tab)
+struct isl_tab *isl_tab_mark_empty(struct isl_tab *tab)
{
if (!tab->empty && tab->need_undo)
- push(ctx, tab, isl_tab_undo_empty, NULL);
+ isl_tab_push(tab, isl_tab_undo_empty);
tab->empty = 1;
+ return tab;
}
/* Given a row number "row" and a column number "col", pivot the tableau
- * such that the associated variable are interchanged.
+ * such that the associated variables are interchanged.
* The given row in the tableau expresses
*
* x_r = a_r0 + \sum_i a_ri x_i
* s(n_rc)d_r n_jc/(|n_rc| d_j) (n_ji |n_rc| - s(n_rc)n_jc n_ri)/(|n_rc| d_j)
*
*/
-static void pivot(struct isl_ctx *ctx,
- struct isl_tab *tab, int row, int col)
+void isl_tab_pivot(struct isl_tab *tab, int row, int col)
{
int i, j;
int sgn;
}
isl_int_mul(mat->row[i][2 + col],
mat->row[i][2 + col], mat->row[row][2 + col]);
- if (!isl_int_is_one(mat->row[row][0]))
+ if (!isl_int_is_one(mat->row[i][0]))
isl_seq_normalize(mat->row[i], 2 + tab->n_col);
}
t = tab->row_var[row];
tab->row_var[row] = tab->col_var[col];
tab->col_var[col] = t;
- var = var_from_row(ctx, tab, row);
+ var = isl_tab_var_from_row(tab, row);
var->is_row = 1;
var->index = row;
- var = var_from_col(ctx, tab, col);
+ var = var_from_col(tab, col);
var->is_row = 0;
var->index = col;
if (tab->in_undo)
for (i = tab->n_redundant; i < tab->n_row; ++i) {
if (isl_int_is_zero(mat->row[i][2 + col]))
continue;
- if (!var_from_row(ctx, tab, i)->frozen &&
- is_redundant(ctx, tab, i))
- if (mark_redundant(ctx, tab, i))
+ if (!isl_tab_var_from_row(tab, i)->frozen &&
+ isl_tab_row_is_redundant(tab, i))
+ if (isl_tab_mark_redundant(tab, i))
--i;
}
}
/* If "var" represents a column variable, then pivot is up (sgn > 0)
* or down (sgn < 0) to a row. The variable is assumed not to be
* unbounded in the specified direction.
+ * If sgn = 0, then the variable is unbounded in both directions,
+ * and we pivot with any row we can find.
*/
-static void to_row(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var, int sign)
+static void to_row(struct isl_tab *tab, struct isl_tab_var *var, int sign)
{
int r;
if (var->is_row)
return;
- r = pivot_row(ctx, tab, NULL, sign, var->index);
- isl_assert(ctx, r >= 0, return);
- pivot(ctx, tab, r, var->index);
+ if (sign == 0) {
+ for (r = tab->n_redundant; r < tab->n_row; ++r)
+ if (!isl_int_is_zero(tab->mat->row[r][2 + var->index]))
+ break;
+ isl_assert(tab->mat->ctx, r < tab->n_row, return);
+ } else {
+ r = pivot_row(tab, NULL, sign, var->index);
+ isl_assert(tab->mat->ctx, r >= 0, return);
+ }
+
+ isl_tab_pivot(tab, r, var->index);
}
-static void check_table(struct isl_ctx *ctx, struct isl_tab *tab)
+static void check_table(struct isl_tab *tab)
{
int i;
if (tab->empty)
return;
for (i = 0; i < tab->n_row; ++i) {
- if (!var_from_row(ctx, tab, i)->is_nonneg)
+ if (!isl_tab_var_from_row(tab, i)->is_nonneg)
continue;
assert(!isl_int_is_neg(tab->mat->row[i][1]));
}
* - the sample value is positive
* - the variable is pivoted into a manifestly unbounded column
*/
-static int sign_of_max(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int sign_of_max(struct isl_tab *tab, struct isl_tab_var *var)
{
int row, col;
- if (max_is_manifestly_unbounded(ctx, tab, var))
+ if (max_is_manifestly_unbounded(tab, var))
return 1;
- to_row(ctx, tab, var, 1);
+ to_row(tab, var, 1);
while (!isl_int_is_pos(tab->mat->row[var->index][1])) {
- find_pivot(ctx, tab, var, var, 1, &row, &col);
+ find_pivot(tab, var, var, 1, &row, &col);
if (row == -1)
return isl_int_sgn(tab->mat->row[var->index][1]);
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
if (!var->is_row) /* manifestly unbounded */
return 1;
}
* Return the sign of the sample value after the pivots have been
* performed.
*/
-static int restore_row(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int restore_row(struct isl_tab *tab, struct isl_tab_var *var)
{
int row, col;
while (isl_int_is_neg(tab->mat->row[var->index][1])) {
- find_pivot(ctx, tab, var, var, 1, &row, &col);
+ find_pivot(tab, var, var, 1, &row, &col);
if (row == -1)
break;
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
if (!var->is_row) /* manifestly unbounded */
return 1;
}
* function, "var" is still a row variable, but its sample
* value may not be non-negative, even if the function returns 1.
*/
-static int at_least_zero(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int at_least_zero(struct isl_tab *tab, struct isl_tab_var *var)
{
int row, col;
while (isl_int_is_neg(tab->mat->row[var->index][1])) {
- find_pivot(ctx, tab, var, var, 1, &row, &col);
+ find_pivot(tab, var, var, 1, &row, &col);
if (row == -1)
break;
if (row == var->index) /* manifestly unbounded */
return 1;
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
}
return !isl_int_is_neg(tab->mat->row[var->index][1]);
}
* In that case we look for upward pivots until we reach a non-negative
* value again.
*/
-static int sign_of_min(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int sign_of_min(struct isl_tab *tab, struct isl_tab_var *var)
{
int row, col;
struct isl_tab_var *pivot_var;
- if (min_is_manifestly_unbounded(ctx, tab, var))
+ if (min_is_manifestly_unbounded(tab, var))
return -1;
if (!var->is_row) {
col = var->index;
- row = pivot_row(ctx, tab, NULL, -1, col);
- pivot_var = var_from_col(ctx, tab, col);
- pivot(ctx, tab, row, col);
+ row = pivot_row(tab, NULL, -1, col);
+ pivot_var = var_from_col(tab, col);
+ isl_tab_pivot(tab, row, col);
if (var->is_redundant)
return 0;
if (isl_int_is_neg(tab->mat->row[var->index][1])) {
if (var->is_nonneg) {
if (!pivot_var->is_redundant &&
pivot_var->index == row)
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
else
- restore_row(ctx, tab, var);
+ restore_row(tab, var);
}
return -1;
}
if (var->is_redundant)
return 0;
while (!isl_int_is_neg(tab->mat->row[var->index][1])) {
- find_pivot(ctx, tab, var, var, -1, &row, &col);
+ find_pivot(tab, var, var, -1, &row, &col);
if (row == var->index)
return -1;
if (row == -1)
return isl_int_sgn(tab->mat->row[var->index][1]);
- pivot_var = var_from_col(ctx, tab, col);
- pivot(ctx, tab, row, col);
+ pivot_var = var_from_col(tab, col);
+ isl_tab_pivot(tab, row, col);
if (var->is_redundant)
return 0;
}
if (var->is_nonneg) {
/* pivot back to non-negative value */
if (!pivot_var->is_redundant && pivot_var->index == row)
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
else
- restore_row(ctx, tab, var);
+ restore_row(tab, var);
}
return -1;
}
* the function is called and will be made non-negative again before
* the function returns.
*/
-static int min_at_most_neg_one(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+int isl_tab_min_at_most_neg_one(struct isl_tab *tab, struct isl_tab_var *var)
{
int row, col;
struct isl_tab_var *pivot_var;
- if (min_is_manifestly_unbounded(ctx, tab, var))
+ if (min_is_manifestly_unbounded(tab, var))
return 1;
if (!var->is_row) {
col = var->index;
- row = pivot_row(ctx, tab, NULL, -1, col);
- pivot_var = var_from_col(ctx, tab, col);
- pivot(ctx, tab, row, col);
+ row = pivot_row(tab, NULL, -1, col);
+ pivot_var = var_from_col(tab, col);
+ isl_tab_pivot(tab, row, col);
if (var->is_redundant)
return 0;
if (isl_int_is_neg(tab->mat->row[var->index][1]) &&
if (var->is_nonneg) {
if (!pivot_var->is_redundant &&
pivot_var->index == row)
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
else
- restore_row(ctx, tab, var);
+ restore_row(tab, var);
}
return 1;
}
if (var->is_redundant)
return 0;
do {
- find_pivot(ctx, tab, var, var, -1, &row, &col);
+ find_pivot(tab, var, var, -1, &row, &col);
if (row == var->index)
return 1;
if (row == -1)
return 0;
- pivot_var = var_from_col(ctx, tab, col);
- pivot(ctx, tab, row, col);
+ pivot_var = var_from_col(tab, col);
+ isl_tab_pivot(tab, row, col);
if (var->is_redundant)
return 0;
} while (!isl_int_is_neg(tab->mat->row[var->index][1]) ||
if (var->is_nonneg) {
/* pivot back to non-negative value */
if (!pivot_var->is_redundant && pivot_var->index == row)
- pivot(ctx, tab, row, col);
- restore_row(ctx, tab, var);
+ isl_tab_pivot(tab, row, col);
+ restore_row(tab, var);
}
return 1;
}
/* Return 1 if "var" can attain values >= 1.
* Return 0 otherwise.
*/
-static int at_least_one(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static int at_least_one(struct isl_tab *tab, struct isl_tab_var *var)
{
int row, col;
isl_int *r;
- if (max_is_manifestly_unbounded(ctx, tab, var))
+ if (max_is_manifestly_unbounded(tab, var))
return 1;
- to_row(ctx, tab, var, 1);
+ to_row(tab, var, 1);
r = tab->mat->row[var->index];
while (isl_int_lt(r[1], r[0])) {
- find_pivot(ctx, tab, var, var, 1, &row, &col);
+ find_pivot(tab, var, var, 1, &row, &col);
if (row == -1)
return isl_int_ge(r[1], r[0]);
if (row == var->index) /* manifestly unbounded */
return 1;
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
}
return 1;
}
-static void swap_cols(struct isl_ctx *ctx,
- struct isl_tab *tab, int col1, int col2)
+static void swap_cols(struct isl_tab *tab, int col1, int col2)
{
int t;
t = tab->col_var[col1];
tab->col_var[col1] = tab->col_var[col2];
tab->col_var[col2] = t;
- var_from_col(ctx, tab, col1)->index = col1;
- var_from_col(ctx, tab, col2)->index = col2;
- tab->mat = isl_mat_swap_cols(ctx, tab->mat, 2 + col1, 2 + col2);
+ var_from_col(tab, col1)->index = col1;
+ var_from_col(tab, col2)->index = col2;
+ tab->mat = isl_mat_swap_cols(tab->mat, 2 + col1, 2 + col2);
}
/* Mark column with index "col" as representing a zero variable.
* column number may now contain a different column that
* hasn't been checked yet.
*/
-static int kill_col(struct isl_ctx *ctx,
- struct isl_tab *tab, int col)
+int isl_tab_kill_col(struct isl_tab *tab, int col)
{
- var_from_col(ctx, tab, col)->is_zero = 1;
+ var_from_col(tab, col)->is_zero = 1;
if (tab->need_undo) {
- push(ctx, tab, isl_tab_undo_zero, var_from_col(ctx, tab, col));
+ isl_tab_push_var(tab, isl_tab_undo_zero, var_from_col(tab, col));
if (col != tab->n_dead)
- swap_cols(ctx, tab, col, tab->n_dead);
+ swap_cols(tab, col, tab->n_dead);
tab->n_dead++;
return 0;
} else {
if (col != tab->n_col - 1)
- swap_cols(ctx, tab, col, tab->n_col - 1);
- var_from_col(ctx, tab, tab->n_col - 1)->index = -1;
+ swap_cols(tab, col, tab->n_col - 1);
+ var_from_col(tab, tab->n_col - 1)->index = -1;
tab->n_col--;
return 1;
}
* then also be written as the negative sum of non-negative variables
* and must therefore also be zero.
*/
-static void close_row(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static void close_row(struct isl_tab *tab, struct isl_tab_var *var)
{
int j;
struct isl_mat *mat = tab->mat;
- isl_assert(ctx, var->is_nonneg, return);
+ isl_assert(tab->mat->ctx, var->is_nonneg, return);
var->is_zero = 1;
for (j = tab->n_dead; j < tab->n_col; ++j) {
if (isl_int_is_zero(mat->row[var->index][2 + j]))
continue;
- isl_assert(ctx, isl_int_is_neg(mat->row[var->index][2 + j]),
- return);
- if (kill_col(ctx, tab, j))
+ isl_assert(tab->mat->ctx,
+ isl_int_is_neg(mat->row[var->index][2 + j]), return);
+ if (isl_tab_kill_col(tab, j))
--j;
}
- mark_redundant(ctx, tab, var->index);
+ isl_tab_mark_redundant(tab, var->index);
+}
+
+/* Add a constraint to the tableau and allocate a row for it.
+ * Return the index into the constraint array "con".
+ */
+int isl_tab_allocate_con(struct isl_tab *tab)
+{
+ int r;
+
+ isl_assert(tab->mat->ctx, tab->n_row < tab->mat->n_row, return -1);
+
+ r = tab->n_con;
+ tab->con[r].index = tab->n_row;
+ tab->con[r].is_row = 1;
+ tab->con[r].is_nonneg = 0;
+ tab->con[r].is_zero = 0;
+ tab->con[r].is_redundant = 0;
+ tab->con[r].frozen = 0;
+ tab->row_var[tab->n_row] = ~r;
+
+ tab->n_row++;
+ tab->n_con++;
+ isl_tab_push_var(tab, isl_tab_undo_allocate, &tab->con[r]);
+
+ return r;
}
/* Add a row to the tableau. The row is given as an affine combination
*
* with g the gcd of d_r and d_x and m the lcm of d_r and d_x.
*/
-static int add_row(struct isl_ctx *ctx, struct isl_tab *tab, isl_int *line)
+int isl_tab_add_row(struct isl_tab *tab, isl_int *line)
{
int i;
- unsigned r;
+ int r;
isl_int *row;
isl_int a, b;
- isl_assert(ctx, tab->n_row < tab->mat->n_row, return -1);
+ r = isl_tab_allocate_con(tab);
+ if (r < 0)
+ return -1;
isl_int_init(a);
isl_int_init(b);
- r = tab->n_con;
- tab->con[r].index = tab->n_row;
- tab->con[r].is_row = 1;
- tab->con[r].is_nonneg = 0;
- tab->con[r].is_zero = 0;
- tab->con[r].is_redundant = 0;
- tab->con[r].frozen = 0;
- tab->row_var[tab->n_row] = ~r;
- row = tab->mat->row[tab->n_row];
+ row = tab->mat->row[tab->con[r].index];
isl_int_set_si(row[0], 1);
isl_int_set(row[1], line[0]);
isl_seq_clr(row + 2, tab->n_col);
line[1 + i], row[0]);
}
isl_seq_normalize(row, 2 + tab->n_col);
- tab->n_row++;
- tab->n_con++;
- push(ctx, tab, isl_tab_undo_allocate, &tab->con[r]);
isl_int_clear(a);
isl_int_clear(b);
return r;
}
-static int drop_row(struct isl_ctx *ctx, struct isl_tab *tab, int row)
+static int drop_row(struct isl_tab *tab, int row)
{
- isl_assert(ctx, ~tab->row_var[row] == tab->n_con - 1, return -1);
+ isl_assert(tab->mat->ctx, ~tab->row_var[row] == tab->n_con - 1, return -1);
if (row != tab->n_row - 1)
- swap_rows(ctx, tab, row, tab->n_row - 1);
+ swap_rows(tab, row, tab->n_row - 1);
tab->n_row--;
tab->n_con--;
return 0;
/* Add inequality "ineq" and check if it conflicts with the
* previously added constraints or if it is obviously redundant.
*/
-struct isl_tab *isl_tab_add_ineq(struct isl_ctx *ctx,
- struct isl_tab *tab, isl_int *ineq)
+struct isl_tab *isl_tab_add_ineq(struct isl_tab *tab, isl_int *ineq)
{
int r;
int sgn;
if (!tab)
return NULL;
- r = add_row(ctx, tab, ineq);
+ r = isl_tab_add_row(tab, ineq);
if (r < 0)
goto error;
tab->con[r].is_nonneg = 1;
- push(ctx, tab, isl_tab_undo_nonneg, &tab->con[r]);
- if (is_redundant(ctx, tab, tab->con[r].index)) {
- mark_redundant(ctx, tab, tab->con[r].index);
+ isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ if (isl_tab_row_is_redundant(tab, tab->con[r].index)) {
+ isl_tab_mark_redundant(tab, tab->con[r].index);
return tab;
}
- sgn = restore_row(ctx, tab, &tab->con[r]);
+ sgn = restore_row(tab, &tab->con[r]);
if (sgn < 0)
- mark_empty(ctx, tab);
- else if (tab->con[r].is_row &&
- is_redundant(ctx, tab, tab->con[r].index))
- mark_redundant(ctx, tab, tab->con[r].index);
+ return isl_tab_mark_empty(tab);
+ if (tab->con[r].is_row && isl_tab_row_is_redundant(tab, tab->con[r].index))
+ isl_tab_mark_redundant(tab, tab->con[r].index);
return tab;
error:
- isl_tab_free(ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
/* Pivot a non-negative variable down until it reaches the value zero
* and then pivot the variable into a column position.
*/
-static int to_col(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+int to_col(struct isl_tab *tab, struct isl_tab_var *var)
{
int i;
int row, col;
return;
while (isl_int_is_pos(tab->mat->row[var->index][1])) {
- find_pivot(ctx, tab, var, NULL, -1, &row, &col);
- isl_assert(ctx, row != -1, return -1);
- pivot(ctx, tab, row, col);
+ find_pivot(tab, var, NULL, -1, &row, &col);
+ isl_assert(tab->mat->ctx, row != -1, return -1);
+ isl_tab_pivot(tab, row, col);
if (!var->is_row)
return;
}
if (!isl_int_is_zero(tab->mat->row[var->index][2 + i]))
break;
- isl_assert(ctx, i < tab->n_col, return -1);
- pivot(ctx, tab, var->index, i);
+ isl_assert(tab->mat->ctx, i < tab->n_col, return -1);
+ isl_tab_pivot(tab, var->index, i);
return 0;
}
* Adding the equalities is currently only really useful for a later call
* to isl_tab_ineq_type.
*/
-static struct isl_tab *add_eq(struct isl_ctx *ctx,
- struct isl_tab *tab, isl_int *eq)
+static struct isl_tab *add_eq(struct isl_tab *tab, isl_int *eq)
{
int i;
int r;
if (!tab)
return NULL;
- r = add_row(ctx, tab, eq);
+ r = isl_tab_add_row(tab, eq);
if (r < 0)
goto error;
r = tab->con[r].index;
- for (i = tab->n_dead; i < tab->n_col; ++i) {
- if (isl_int_is_zero(tab->mat->row[r][2 + i]))
- continue;
- pivot(ctx, tab, r, i);
- kill_col(ctx, tab, i);
- break;
- }
+ i = isl_seq_first_non_zero(tab->mat->row[r] + 2 + tab->n_dead,
+ tab->n_col - tab->n_dead);
+ isl_assert(tab->mat->ctx, i >= 0, goto error);
+ i += tab->n_dead;
+ isl_tab_pivot(tab, r, i);
+ isl_tab_kill_col(tab, i);
tab->n_eq++;
return tab;
error:
- isl_tab_free(ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
/* Add an equality that is known to be valid for the given tableau.
*/
-struct isl_tab *isl_tab_add_valid_eq(struct isl_ctx *ctx,
- struct isl_tab *tab, isl_int *eq)
+struct isl_tab *isl_tab_add_valid_eq(struct isl_tab *tab, isl_int *eq)
{
struct isl_tab_var *var;
int i;
if (!tab)
return NULL;
- r = add_row(ctx, tab, eq);
+ r = isl_tab_add_row(tab, eq);
if (r < 0)
goto error;
isl_seq_neg(tab->mat->row[r] + 1, tab->mat->row[r] + 1,
1 + tab->n_col);
var->is_nonneg = 1;
- if (to_col(ctx, tab, var) < 0)
+ if (to_col(tab, var) < 0)
goto error;
var->is_nonneg = 0;
- kill_col(ctx, tab, var->index);
+ isl_tab_kill_col(tab, var->index);
return tab;
error:
- isl_tab_free(ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
if (!tab)
return NULL;
tab->rational = ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL);
- if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY)) {
- mark_empty(bmap->ctx, tab);
- return tab;
- }
+ if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
+ return isl_tab_mark_empty(tab);
for (i = 0; i < bmap->n_eq; ++i) {
- tab = add_eq(bmap->ctx, tab, bmap->eq[i]);
+ tab = add_eq(tab, bmap->eq[i]);
if (!tab)
return tab;
}
for (i = 0; i < bmap->n_ineq; ++i) {
- tab = isl_tab_add_ineq(bmap->ctx, tab, bmap->ineq[i]);
+ tab = isl_tab_add_ineq(tab, bmap->ineq[i]);
if (!tab || tab->empty)
return tab;
}
isl_int_init(cst);
for (i = 0; i < bmap->n_eq; ++i) {
isl_int_swap(bmap->eq[i][0], cst);
- tab = add_eq(bmap->ctx, tab, bmap->eq[i]);
+ tab = add_eq(tab, bmap->eq[i]);
isl_int_swap(bmap->eq[i][0], cst);
if (!tab)
goto done;
for (i = 0; i < bmap->n_ineq; ++i) {
int r;
isl_int_swap(bmap->ineq[i][0], cst);
- r = add_row(bmap->ctx, tab, bmap->ineq[i]);
+ r = isl_tab_add_row(tab, bmap->ineq[i]);
isl_int_swap(bmap->ineq[i][0], cst);
if (r < 0)
goto error;
tab->con[r].is_nonneg = 1;
- push(bmap->ctx, tab, isl_tab_undo_nonneg, &tab->con[r]);
+ isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
}
done:
isl_int_clear(cst);
return tab;
error:
isl_int_clear(cst);
- isl_tab_free(bmap->ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
/* Assuming "tab" is the tableau of a cone, check if the cone is
* bounded, i.e., if it is empty or only contains the origin.
*/
-int isl_tab_cone_is_bounded(struct isl_ctx *ctx, struct isl_tab *tab)
+int isl_tab_cone_is_bounded(struct isl_tab *tab)
{
int i;
if (tab->n_dead == tab->n_col)
return 1;
- for (i = tab->n_redundant; i < tab->n_row; ++i) {
- struct isl_tab_var *var;
- var = var_from_row(ctx, tab, i);
- if (!var->is_nonneg)
- continue;
- if (sign_of_max(ctx, tab, var) == 0)
- close_row(ctx, tab, var);
- else
- return 0;
+ for (;;) {
+ for (i = tab->n_redundant; i < tab->n_row; ++i) {
+ struct isl_tab_var *var;
+ var = isl_tab_var_from_row(tab, i);
+ if (!var->is_nonneg)
+ continue;
+ if (sign_of_max(tab, var) != 0)
+ return 0;
+ close_row(tab, var);
+ break;
+ }
if (tab->n_dead == tab->n_col)
return 1;
+ if (i == tab->n_row)
+ return 0;
}
- return 0;
}
-static int sample_is_integer(struct isl_ctx *ctx, struct isl_tab *tab)
+int isl_tab_sample_is_integer(struct isl_tab *tab)
{
int i;
+ if (!tab)
+ return -1;
+
for (i = 0; i < tab->n_var; ++i) {
int row;
if (!tab->var[i].is_row)
return 1;
}
-static struct isl_vec *extract_integer_sample(struct isl_ctx *ctx,
- struct isl_tab *tab)
+static struct isl_vec *extract_integer_sample(struct isl_tab *tab)
{
int i;
struct isl_vec *vec;
- vec = isl_vec_alloc(ctx, 1 + tab->n_var);
+ vec = isl_vec_alloc(tab->mat->ctx, 1 + tab->n_var);
if (!vec)
return NULL;
return vec;
}
-struct isl_vec *isl_tab_get_sample_value(struct isl_ctx *ctx,
- struct isl_tab *tab)
+struct isl_vec *isl_tab_get_sample_value(struct isl_tab *tab)
{
int i;
struct isl_vec *vec;
if (!tab)
return NULL;
- vec = isl_vec_alloc(ctx, 1 + tab->n_var);
+ vec = isl_vec_alloc(tab->mat->ctx, 1 + tab->n_var);
if (!vec)
return NULL;
bmap = isl_basic_map_set_to_empty(bmap);
else
for (i = bmap->n_ineq - 1; i >= 0; --i) {
- if (isl_tab_is_equality(bmap->ctx, tab, n_eq + i))
+ if (isl_tab_is_equality(tab, n_eq + i))
isl_basic_map_inequality_to_equality(bmap, i);
- else if (isl_tab_is_redundant(bmap->ctx, tab, n_eq + i))
+ else if (isl_tab_is_redundant(tab, n_eq + i))
isl_basic_map_drop_inequality(bmap, i);
}
if (!tab->rational &&
- !bmap->sample && sample_is_integer(bmap->ctx, tab))
- bmap->sample = extract_integer_sample(bmap->ctx, tab);
+ !bmap->sample && isl_tab_sample_is_integer(tab))
+ bmap->sample = extract_integer_sample(tab);
return bmap;
}
* the resulting tableau is empty.
* Otherwise, we know the value will be zero and we close the row.
*/
-static struct isl_tab *cut_to_hyperplane(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static struct isl_tab *cut_to_hyperplane(struct isl_tab *tab,
+ struct isl_tab_var *var)
{
unsigned r;
isl_int *row;
int sgn;
- if (extend_cons(ctx, tab, 1) < 0)
+ if (isl_tab_extend_cons(tab, 1) < 0)
goto error;
r = tab->n_con;
tab->n_row++;
tab->n_con++;
- push(ctx, tab, isl_tab_undo_allocate, &tab->con[r]);
+ isl_tab_push_var(tab, isl_tab_undo_allocate, &tab->con[r]);
- sgn = sign_of_max(ctx, tab, &tab->con[r]);
+ sgn = sign_of_max(tab, &tab->con[r]);
if (sgn < 0)
- mark_empty(ctx, tab);
- else {
- tab->con[r].is_nonneg = 1;
- push(ctx, tab, isl_tab_undo_nonneg, &tab->con[r]);
- /* sgn == 0 */
- close_row(ctx, tab, &tab->con[r]);
- }
+ return isl_tab_mark_empty(tab);
+ tab->con[r].is_nonneg = 1;
+ isl_tab_push_var(tab, isl_tab_undo_nonneg, &tab->con[r]);
+ /* sgn == 0 */
+ close_row(tab, &tab->con[r]);
return tab;
error:
- isl_tab_free(ctx, tab);
+ isl_tab_free(tab);
return NULL;
}
* refers to r = r' - 1 by substituting this equality, effectively
* subtracting the coefficient of the column from the constant.
*/
-struct isl_tab *isl_tab_relax(struct isl_ctx *ctx,
- struct isl_tab *tab, int con)
+struct isl_tab *isl_tab_relax(struct isl_tab *tab, int con)
{
struct isl_tab_var *var;
if (!tab)
var = &tab->con[con];
- if (!var->is_row && !max_is_manifestly_unbounded(ctx, tab, var))
- to_row(ctx, tab, var, 1);
+ if (!var->is_row && !max_is_manifestly_unbounded(tab, var))
+ to_row(tab, var, 1);
if (var->is_row)
isl_int_add(tab->mat->row[var->index][1],
}
- push(ctx, tab, isl_tab_undo_relax, var);
+ isl_tab_push_var(tab, isl_tab_undo_relax, var);
return tab;
}
-struct isl_tab *isl_tab_select_facet(struct isl_ctx *ctx,
- struct isl_tab *tab, int con)
+struct isl_tab *isl_tab_select_facet(struct isl_tab *tab, int con)
{
if (!tab)
return NULL;
- return cut_to_hyperplane(ctx, tab, &tab->con[con]);
+ return cut_to_hyperplane(tab, &tab->con[con]);
}
static int may_be_equality(struct isl_tab *tab, int row)
* tableau is integer), then we restrict the value to being zero
* by adding an opposite non-negative variable.
*/
-struct isl_tab *isl_tab_detect_equalities(struct isl_ctx *ctx,
- struct isl_tab *tab)
+struct isl_tab *isl_tab_detect_equalities(struct isl_tab *tab)
{
int i;
unsigned n_marked;
n_marked = 0;
for (i = tab->n_redundant; i < tab->n_row; ++i) {
- struct isl_tab_var *var = var_from_row(ctx, tab, i);
+ struct isl_tab_var *var = isl_tab_var_from_row(tab, i);
var->marked = !var->frozen && var->is_nonneg &&
may_be_equality(tab, i);
if (var->marked)
n_marked++;
}
for (i = tab->n_dead; i < tab->n_col; ++i) {
- struct isl_tab_var *var = var_from_col(ctx, tab, i);
+ struct isl_tab_var *var = var_from_col(tab, i);
var->marked = !var->frozen && var->is_nonneg;
if (var->marked)
n_marked++;
while (n_marked) {
struct isl_tab_var *var;
for (i = tab->n_redundant; i < tab->n_row; ++i) {
- var = var_from_row(ctx, tab, i);
+ var = isl_tab_var_from_row(tab, i);
if (var->marked)
break;
}
if (i == tab->n_row) {
for (i = tab->n_dead; i < tab->n_col; ++i) {
- var = var_from_col(ctx, tab, i);
+ var = var_from_col(tab, i);
if (var->marked)
break;
}
}
var->marked = 0;
n_marked--;
- if (sign_of_max(ctx, tab, var) == 0)
- close_row(ctx, tab, var);
- else if (!tab->rational && !at_least_one(ctx, tab, var)) {
- tab = cut_to_hyperplane(ctx, tab, var);
- return isl_tab_detect_equalities(ctx, tab);
+ if (sign_of_max(tab, var) == 0)
+ close_row(tab, var);
+ else if (!tab->rational && !at_least_one(tab, var)) {
+ tab = cut_to_hyperplane(tab, var);
+ return isl_tab_detect_equalities(tab);
}
for (i = tab->n_redundant; i < tab->n_row; ++i) {
- var = var_from_row(ctx, tab, i);
+ var = isl_tab_var_from_row(tab, i);
if (!var->marked)
continue;
if (may_be_equality(tab, i))
* If not, we mark the row as being redundant (assuming it hasn't
* been detected as being obviously redundant in the mean time).
*/
-struct isl_tab *isl_tab_detect_redundant(struct isl_ctx *ctx,
- struct isl_tab *tab)
+struct isl_tab *isl_tab_detect_redundant(struct isl_tab *tab)
{
int i;
unsigned n_marked;
n_marked = 0;
for (i = tab->n_redundant; i < tab->n_row; ++i) {
- struct isl_tab_var *var = var_from_row(ctx, tab, i);
+ struct isl_tab_var *var = isl_tab_var_from_row(tab, i);
var->marked = !var->frozen && var->is_nonneg;
if (var->marked)
n_marked++;
}
for (i = tab->n_dead; i < tab->n_col; ++i) {
- struct isl_tab_var *var = var_from_col(ctx, tab, i);
+ struct isl_tab_var *var = var_from_col(tab, i);
var->marked = !var->frozen && var->is_nonneg &&
- !min_is_manifestly_unbounded(ctx, tab, var);
+ !min_is_manifestly_unbounded(tab, var);
if (var->marked)
n_marked++;
}
while (n_marked) {
struct isl_tab_var *var;
for (i = tab->n_redundant; i < tab->n_row; ++i) {
- var = var_from_row(ctx, tab, i);
+ var = isl_tab_var_from_row(tab, i);
if (var->marked)
break;
}
if (i == tab->n_row) {
for (i = tab->n_dead; i < tab->n_col; ++i) {
- var = var_from_col(ctx, tab, i);
+ var = var_from_col(tab, i);
if (var->marked)
break;
}
}
var->marked = 0;
n_marked--;
- if ((tab->rational ? (sign_of_min(ctx, tab, var) >= 0)
- : !min_at_most_neg_one(ctx, tab, var)) &&
+ if ((tab->rational ? (sign_of_min(tab, var) >= 0)
+ : !isl_tab_min_at_most_neg_one(tab, var)) &&
!var->is_redundant)
- mark_redundant(ctx, tab, var->index);
+ isl_tab_mark_redundant(tab, var->index);
for (i = tab->n_dead; i < tab->n_col; ++i) {
- var = var_from_col(ctx, tab, i);
+ var = var_from_col(tab, i);
if (!var->marked)
continue;
- if (!min_is_manifestly_unbounded(ctx, tab, var))
+ if (!min_is_manifestly_unbounded(tab, var))
continue;
var->marked = 0;
n_marked--;
return tab;
}
-int isl_tab_is_equality(struct isl_ctx *ctx, struct isl_tab *tab, int con)
+int isl_tab_is_equality(struct isl_tab *tab, int con)
{
int row;
* The return value reflects the nature of the result (empty, unbounded,
* minmimal value returned in *opt).
*/
-enum isl_lp_result isl_tab_min(struct isl_ctx *ctx, struct isl_tab *tab,
+enum isl_lp_result isl_tab_min(struct isl_tab *tab,
isl_int *f, isl_int denom, isl_int *opt, isl_int *opt_denom,
unsigned flags)
{
if (tab->empty)
return isl_lp_empty;
- snap = isl_tab_snap(ctx, tab);
- r = add_row(ctx, tab, f);
+ snap = isl_tab_snap(tab);
+ r = isl_tab_add_row(tab, f);
if (r < 0)
return isl_lp_error;
var = &tab->con[r];
tab->mat->row[var->index][0], denom);
for (;;) {
int row, col;
- find_pivot(ctx, tab, var, var, -1, &row, &col);
+ find_pivot(tab, var, var, -1, &row, &col);
if (row == var->index) {
res = isl_lp_unbounded;
break;
}
if (row == -1)
break;
- pivot(ctx, tab, row, col);
+ isl_tab_pivot(tab, row, col);
}
- if (isl_tab_rollback(ctx, tab, snap) < 0)
+ if (isl_tab_rollback(tab, snap) < 0)
return isl_lp_error;
if (ISL_FL_ISSET(flags, ISL_TAB_SAVE_DUAL)) {
int i;
isl_vec_free(tab->dual);
- tab->dual = isl_vec_alloc(ctx, 1 + tab->n_con);
+ tab->dual = isl_vec_alloc(tab->mat->ctx, 1 + tab->n_con);
if (!tab->dual)
return isl_lp_error;
isl_int_set(tab->dual->el[0], tab->mat->row[var->index][0]);
return res;
}
-int isl_tab_is_redundant(struct isl_ctx *ctx, struct isl_tab *tab, int con)
+int isl_tab_is_redundant(struct isl_tab *tab, int con)
{
int row;
unsigned n_col;
/* Take a snapshot of the tableau that can be restored by s call to
* isl_tab_rollback.
*/
-struct isl_tab_undo *isl_tab_snap(struct isl_ctx *ctx, struct isl_tab *tab)
+struct isl_tab_undo *isl_tab_snap(struct isl_tab *tab)
{
if (!tab)
return NULL;
/* Undo the operation performed by isl_tab_relax.
*/
-static void unrelax(struct isl_ctx *ctx,
- struct isl_tab *tab, struct isl_tab_var *var)
+static void unrelax(struct isl_tab *tab, struct isl_tab_var *var)
{
- if (!var->is_row && !max_is_manifestly_unbounded(ctx, tab, var))
- to_row(ctx, tab, var, 1);
+ if (!var->is_row && !max_is_manifestly_unbounded(tab, var))
+ to_row(tab, var, 1);
if (var->is_row)
isl_int_sub(tab->mat->row[var->index][1],
}
}
-static void perform_undo(struct isl_ctx *ctx, struct isl_tab *tab,
- struct isl_tab_undo *undo)
+static void perform_undo_var(struct isl_tab *tab, struct isl_tab_undo *undo)
{
+ struct isl_tab_var *var = var_from_index(tab, undo->u.var_index);
switch(undo->type) {
- case isl_tab_undo_empty:
- tab->empty = 0;
- break;
case isl_tab_undo_nonneg:
- undo->var->is_nonneg = 0;
+ var->is_nonneg = 0;
break;
case isl_tab_undo_redundant:
- undo->var->is_redundant = 0;
+ var->is_redundant = 0;
tab->n_redundant--;
break;
case isl_tab_undo_zero:
- undo->var->is_zero = 0;
+ var->is_zero = 0;
tab->n_dead--;
break;
case isl_tab_undo_allocate:
- if (!undo->var->is_row) {
- if (max_is_manifestly_unbounded(ctx, tab, undo->var))
- to_row(ctx, tab, undo->var, -1);
+ if (!var->is_row) {
+ if (!max_is_manifestly_unbounded(tab, var))
+ to_row(tab, var, 1);
+ else if (!min_is_manifestly_unbounded(tab, var))
+ to_row(tab, var, -1);
else
- to_row(ctx, tab, undo->var, 1);
+ to_row(tab, var, 0);
}
- drop_row(ctx, tab, undo->var->index);
+ drop_row(tab, var->index);
+ break;
+ case isl_tab_undo_relax:
+ unrelax(tab, var);
+ break;
+ }
+}
+
+/* Restore the tableau to the state where the basic variables
+ * are those in "col_var".
+ * We first construct a list of variables that are currently in
+ * the basis, but shouldn't. Then we iterate over all variables
+ * that should be in the basis and for each one that is currently
+ * not in the basis, we exchange it with one of the elements of the
+ * list constructed before.
+ * We can always find an appropriate variable to pivot with because
+ * the current basis is mapped to the old basis by a non-singular
+ * matrix and so we can never end up with a zero row.
+ */
+static int restore_basis(struct isl_tab *tab, int *col_var)
+{
+ int i, j;
+ int n_extra = 0;
+ int *extra = NULL; /* current columns that contain bad stuff */
+ unsigned off = 2;
+
+ extra = isl_alloc_array(tab->mat->ctx, int, tab->n_col);
+ if (!extra)
+ goto error;
+ for (i = 0; i < tab->n_col; ++i) {
+ for (j = 0; j < tab->n_col; ++j)
+ if (tab->col_var[i] == col_var[j])
+ break;
+ if (j < tab->n_col)
+ continue;
+ extra[n_extra++] = i;
+ }
+ for (i = 0; i < tab->n_col && n_extra > 0; ++i) {
+ struct isl_tab_var *var;
+ int row;
+
+ for (j = 0; j < tab->n_col; ++j)
+ if (col_var[i] == tab->col_var[j])
+ break;
+ if (j < tab->n_col)
+ continue;
+ var = var_from_index(tab, col_var[i]);
+ row = var->index;
+ for (j = 0; j < n_extra; ++j)
+ if (!isl_int_is_zero(tab->mat->row[row][off+extra[j]]))
+ break;
+ isl_assert(tab->mat->ctx, j < n_extra, goto error);
+ isl_tab_pivot(tab, row, extra[j]);
+ extra[j] = extra[--n_extra];
+ }
+
+ free(extra);
+ free(col_var);
+ return 0;
+error:
+ free(extra);
+ free(col_var);
+ return -1;
+}
+
+static int perform_undo(struct isl_tab *tab, struct isl_tab_undo *undo)
+{
+ switch (undo->type) {
+ case isl_tab_undo_empty:
+ tab->empty = 0;
break;
+ case isl_tab_undo_nonneg:
+ case isl_tab_undo_redundant:
+ case isl_tab_undo_zero:
+ case isl_tab_undo_allocate:
case isl_tab_undo_relax:
- unrelax(ctx, tab, undo->var);
+ perform_undo_var(tab, undo);
+ break;
+ case isl_tab_undo_saved_basis:
+ if (restore_basis(tab, undo->u.col_var) < 0)
+ return -1;
break;
+ default:
+ isl_assert(tab->mat->ctx, 0, return -1);
}
+ return 0;
}
/* Return the tableau to the state it was in when the snapshot "snap"
* was taken.
*/
-int isl_tab_rollback(struct isl_ctx *ctx, struct isl_tab *tab,
- struct isl_tab_undo *snap)
+int isl_tab_rollback(struct isl_tab *tab, struct isl_tab_undo *snap)
{
struct isl_tab_undo *undo, *next;
next = undo->next;
if (undo == snap)
break;
- perform_undo(ctx, tab, undo);
+ if (perform_undo(tab, undo) < 0) {
+ free_undo(tab);
+ tab->in_undo = 0;
+ return -1;
+ }
free(undo);
}
tab->in_undo = 0;
* of the tableau, then the inequality is adjacent (but opposite)
* to the inequality r'.
*/
-static enum isl_ineq_type separation_type(struct isl_ctx *ctx,
- struct isl_tab *tab, unsigned row)
+static enum isl_ineq_type separation_type(struct isl_tab *tab, unsigned row)
{
int pos;
* isl_ineq_adj_eq: adjacent to an equality
* isl_ineq_adj_ineq: adjacent to an inequality.
*/
-enum isl_ineq_type isl_tab_ineq_type(struct isl_ctx *ctx, struct isl_tab *tab,
- isl_int *ineq)
+enum isl_ineq_type isl_tab_ineq_type(struct isl_tab *tab, isl_int *ineq)
{
enum isl_ineq_type type = isl_ineq_error;
struct isl_tab_undo *snap = NULL;
if (!tab)
return isl_ineq_error;
- if (extend_cons(ctx, tab, 1) < 0)
+ if (isl_tab_extend_cons(tab, 1) < 0)
return isl_ineq_error;
- snap = isl_tab_snap(ctx, tab);
+ snap = isl_tab_snap(tab);
- con = add_row(ctx, tab, ineq);
+ con = isl_tab_add_row(tab, ineq);
if (con < 0)
goto error;
row = tab->con[con].index;
- if (is_redundant(ctx, tab, row))
+ if (isl_tab_row_is_redundant(tab, row))
type = isl_ineq_redundant;
else if (isl_int_is_neg(tab->mat->row[row][1]) &&
(tab->rational ||
isl_int_abs_ge(tab->mat->row[row][1],
tab->mat->row[row][0]))) {
- if (at_least_zero(ctx, tab, &tab->con[con]))
+ if (at_least_zero(tab, &tab->con[con]))
type = isl_ineq_cut;
else
- type = separation_type(ctx, tab, row);
- } else if (tab->rational ? (sign_of_min(ctx, tab, &tab->con[con]) < 0)
- : min_at_most_neg_one(ctx, tab, &tab->con[con]))
+ type = separation_type(tab, row);
+ } else if (tab->rational ? (sign_of_min(tab, &tab->con[con]) < 0)
+ : isl_tab_min_at_most_neg_one(tab, &tab->con[con]))
type = isl_ineq_cut;
else
type = isl_ineq_redundant;
- if (isl_tab_rollback(ctx, tab, snap))
+ if (isl_tab_rollback(tab, snap))
return isl_ineq_error;
return type;
error:
- isl_tab_rollback(ctx, tab, snap);
+ isl_tab_rollback(tab, snap);
return isl_ineq_error;
}
-void isl_tab_dump(struct isl_ctx *ctx, struct isl_tab *tab,
- FILE *out, int indent)
+void isl_tab_dump(struct isl_tab *tab, FILE *out, int indent)
{
unsigned r, c;
int i;
fprintf(out, "%*s[", indent, "");
for (i = 0; i < tab->n_var; ++i) {
if (i)
- fprintf(out, ", ");
+ fprintf(out, (i == tab->n_param ||
+ i == tab->n_var - tab->n_div) ? "; "
+ : ", ");
fprintf(out, "%c%d%s", tab->var[i].is_row ? 'r' : 'c',
tab->var[i].index,
tab->var[i].is_zero ? " [=0]" :
if (i)
fprintf(out, ", ");
fprintf(out, "r%d: %d%s", i, tab->row_var[i],
- var_from_row(ctx, tab, i)->is_nonneg ? " [>=0]" : "");
+ isl_tab_var_from_row(tab, i)->is_nonneg ? " [>=0]" : "");
}
fprintf(out, "]\n");
fprintf(out, "%*s[", indent, "");
if (i)
fprintf(out, ", ");
fprintf(out, "c%d: %d%s", i, tab->col_var[i],
- var_from_col(ctx, tab, i)->is_nonneg ? " [>=0]" : "");
+ var_from_col(tab, i)->is_nonneg ? " [>=0]" : "");
}
fprintf(out, "]\n");
r = tab->mat->n_row;
tab->mat->n_row = tab->n_row;
c = tab->mat->n_col;
tab->mat->n_col = 2 + tab->n_col;
- isl_mat_dump(ctx, tab->mat, out, indent);
+ isl_mat_dump(tab->mat, out, indent);
tab->mat->n_row = r;
tab->mat->n_col = c;
}
projects / platform / upstream / isl.git / blobdiff