File: isl_tab.h

package info (click to toggle)
isl 0.20-2
  • links: PTS
  • area: main
  • in suites: buster, sid
  • size: 12,708 kB
  • sloc: ansic: 125,702; python: 5,770; sh: 4,291; cpp: 1,057; makefile: 497; lisp: 54; perl: 9
file content (337 lines) | stat: -rw-r--r-- 12,327 bytes parent folder | download | duplicates (11)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
/*
 * Copyright 2008-2009 Katholieke Universiteit Leuven
 *
 * Use of this software is governed by the MIT license
 *
 * Written by Sven Verdoolaege, K.U.Leuven, Departement
 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
 */

#ifndef ISL_TAB_H
#define ISL_TAB_H

#include <isl/lp.h>
#include <isl/map.h>
#include <isl/mat.h>
#include <isl/set.h>
#include <isl_config.h>

struct isl_tab_var {
	int index;
	unsigned is_row : 1;
	unsigned is_nonneg : 1;
	unsigned is_zero : 1;
	unsigned is_redundant : 1;
	unsigned marked : 1;
	unsigned frozen : 1;
	unsigned negated : 1;
};

enum isl_tab_undo_type {
	isl_tab_undo_bottom,
	isl_tab_undo_rational,
	isl_tab_undo_empty,
	isl_tab_undo_nonneg,
	isl_tab_undo_redundant,
	isl_tab_undo_freeze,
	isl_tab_undo_zero,
	isl_tab_undo_allocate,
	isl_tab_undo_relax,
	isl_tab_undo_unrestrict,
	isl_tab_undo_bmap_ineq,
	isl_tab_undo_bmap_eq,
	isl_tab_undo_bmap_div,
	isl_tab_undo_saved_basis,
	isl_tab_undo_drop_sample,
	isl_tab_undo_saved_samples,
	isl_tab_undo_callback,
};

struct isl_tab_callback {
	isl_stat (*run)(struct isl_tab_callback *cb);
};

union isl_tab_undo_val {
	int		var_index;
	int		*col_var;
	int		n;
	struct isl_tab_callback	*callback;
};

struct isl_tab_undo {
	enum isl_tab_undo_type	type;
	union isl_tab_undo_val	u;
	struct isl_tab_undo	*next;
};

/* The tableau maintains equality relations.
 * Each column and each row is associated to a variable or a constraint.
 * The "value" of an inequality constraint is the value of the corresponding
 * slack variable.
 * The "row_var" and "col_var" arrays map column and row indices
 * to indices in the "var" and "con" arrays.  The elements of these
 * arrays maintain extra information about the variables and the constraints.
 * 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.
 * 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
 * expression to the corresponding row variable.
 * The operations on the tableau maintain the property that the sample
 * 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
 * the dead columns are also flagged "is_zero".
 *
 * The first n_redundant rows correspond to inequality constraints
 * that are always satisfied for any value satisfying the non-redundant
 * rows.  The corresponding tab_vars are flagged "is_redundant".
 * A row variable that is flagged "is_zero" is also flagged "is_redundant"
 * since the constraint has been reduced to 0 = 0 and is therefore always
 * satisfied.
 *
 * 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.  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_implicit_equalities and isl_tab_detect_redundant can be used
 * to perform an 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.
 *
 * If "preserve" is set, then we want to keep all constraints in the
 * tableau, even if they turn out to be redundant.
 */
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_row;
	unsigned n_col;
	unsigned n_dead;
	unsigned n_redundant;

	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 *var;
	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_map *bmap;

	unsigned n_sample;
	unsigned n_outside;
	int *sample_index;
	struct isl_mat *samples;

	int n_zero;
	int n_unbounded;
	struct isl_mat *basis;

	int (*conflict)(int con, void *user);
	void *conflict_user;

	unsigned strict_redundant : 1;
	unsigned need_undo : 1;
	unsigned preserve : 1;
	unsigned rational : 1;
	unsigned empty : 1;
	unsigned in_undo : 1;
	unsigned M : 1;
	unsigned cone : 1;
};

struct isl_tab *isl_tab_alloc(struct isl_ctx *ctx,
	unsigned n_row, unsigned n_var, unsigned M);
void isl_tab_free(struct isl_tab *tab);

isl_ctx *isl_tab_get_ctx(struct isl_tab *tab);

__isl_give struct isl_tab *isl_tab_from_basic_map(
	__isl_keep isl_basic_map *bmap, int track);
__isl_give struct isl_tab *isl_tab_from_basic_set(
	__isl_keep isl_basic_set *bset, int track);
struct isl_tab *isl_tab_from_recession_cone(struct isl_basic_set *bset,
	int parametric);
isl_bool isl_tab_cone_is_bounded(struct isl_tab *tab);
struct isl_basic_map *isl_basic_map_update_from_tab(struct isl_basic_map *bmap,
	struct isl_tab *tab);
struct isl_basic_set *isl_basic_set_update_from_tab(struct isl_basic_set *bset,
	struct isl_tab *tab);
int isl_tab_detect_implicit_equalities(struct isl_tab *tab) WARN_UNUSED;
__isl_give isl_basic_map *isl_tab_make_equalities_explicit(struct isl_tab *tab,
	__isl_take isl_basic_map *bmap);
int isl_tab_detect_redundant(struct isl_tab *tab) WARN_UNUSED;
isl_stat isl_tab_restore_redundant(struct isl_tab *tab);
#define ISL_TAB_SAVE_DUAL	(1 << 0)
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) WARN_UNUSED;

isl_stat isl_tab_add_ineq(struct isl_tab *tab, isl_int *ineq) WARN_UNUSED;
int isl_tab_add_eq(struct isl_tab *tab, isl_int *eq) WARN_UNUSED;
int isl_tab_add_valid_eq(struct isl_tab *tab, isl_int *eq) WARN_UNUSED;

int isl_tab_freeze_constraint(struct isl_tab *tab, int con) WARN_UNUSED;

isl_stat isl_tab_track_bmap(struct isl_tab *tab, __isl_take isl_basic_map *bmap)
	WARN_UNUSED;
isl_stat isl_tab_track_bset(struct isl_tab *tab, __isl_take isl_basic_set *bset)
	WARN_UNUSED;
__isl_keep isl_basic_set *isl_tab_peek_bset(struct isl_tab *tab);

int isl_tab_is_equality(struct isl_tab *tab, int con);
int isl_tab_is_redundant(struct isl_tab *tab, int con);

int isl_tab_sample_is_integer(struct isl_tab *tab);
struct isl_vec *isl_tab_get_sample_value(struct isl_tab *tab);

enum isl_ineq_type {
	isl_ineq_error = -1,
	isl_ineq_redundant,
	isl_ineq_separate,
	isl_ineq_cut,
	isl_ineq_adj_eq,
	isl_ineq_adj_ineq,
};

enum isl_ineq_type isl_tab_ineq_type(struct isl_tab *tab, isl_int *ineq);

struct isl_tab_undo *isl_tab_snap(struct isl_tab *tab);
int isl_tab_rollback(struct isl_tab *tab, struct isl_tab_undo *snap) WARN_UNUSED;
isl_bool isl_tab_need_undo(struct isl_tab *tab);
void isl_tab_clear_undo(struct isl_tab *tab);

int isl_tab_relax(struct isl_tab *tab, int con) WARN_UNUSED;
int isl_tab_select_facet(struct isl_tab *tab, int con) WARN_UNUSED;
int isl_tab_unrestrict(struct isl_tab *tab, int con) WARN_UNUSED;

void isl_tab_dump(__isl_keep struct isl_tab *tab);

/* Compute maximum instead of minimum. */
#define ISL_OPT_MAX		(1 << 0)
/* Compute full instead of partial optimum; also, domain argument is NULL. */
#define ISL_OPT_FULL		(1 << 1)
/* Result should be free of (unknown) quantified variables. */
#define ISL_OPT_QE		(1 << 2)
__isl_give isl_map *isl_tab_basic_map_partial_lexopt(
	__isl_take isl_basic_map *bmap, __isl_take isl_basic_set *dom,
	__isl_give isl_set **empty, unsigned flags);
__isl_give isl_pw_multi_aff *isl_tab_basic_map_partial_lexopt_pw_multi_aff(
	__isl_take isl_basic_map *bmap, __isl_take isl_basic_set *dom,
	__isl_give isl_set **empty, unsigned flags);

/* An isl_trivial_region represents a non-triviality region.
 * The region is trivial if applying "trivial" to a given sequence
 * of variables results in a zero vector.
 * pos is the location (starting at 0) of the first variable in the sequence.
 */
struct isl_trivial_region {
	int pos;
	isl_mat *trivial;
};

__isl_give isl_vec *isl_tab_basic_set_non_trivial_lexmin(
	__isl_take isl_basic_set *bset, int n_op, int n_region,
	struct isl_trivial_region *region,
	int (*conflict)(int con, void *user), void *user);

struct isl_tab_lexmin;
typedef struct isl_tab_lexmin isl_tab_lexmin;

__isl_give isl_tab_lexmin *isl_tab_lexmin_from_basic_set(
	__isl_take isl_basic_set *bset);
int isl_tab_lexmin_dim(__isl_keep isl_tab_lexmin *tl);
__isl_give isl_tab_lexmin *isl_tab_lexmin_add_eq(__isl_take isl_tab_lexmin *tl,
	isl_int *eq);
__isl_give isl_tab_lexmin *isl_tab_lexmin_cut_to_integer(
	__isl_take isl_tab_lexmin *tl);
__isl_give isl_vec *isl_tab_lexmin_get_solution(__isl_keep isl_tab_lexmin *tl);
__isl_null isl_tab_lexmin *isl_tab_lexmin_free(__isl_take isl_tab_lexmin *tl);

/* private */

struct isl_tab_var *isl_tab_var_from_row(struct isl_tab *tab, int i);
int isl_tab_mark_redundant(struct isl_tab *tab, int row) WARN_UNUSED;
int isl_tab_mark_rational(struct isl_tab *tab) WARN_UNUSED;
isl_stat isl_tab_mark_empty(struct isl_tab *tab) WARN_UNUSED;
struct isl_tab *isl_tab_dup(struct isl_tab *tab);
struct isl_tab *isl_tab_product(struct isl_tab *tab1, struct isl_tab *tab2);
int isl_tab_extend_cons(struct isl_tab *tab, unsigned n_new) WARN_UNUSED;
int isl_tab_allocate_con(struct isl_tab *tab) WARN_UNUSED;
int isl_tab_extend_vars(struct isl_tab *tab, unsigned n_new) WARN_UNUSED;
int isl_tab_allocate_var(struct isl_tab *tab) WARN_UNUSED;
int isl_tab_insert_var(struct isl_tab *tab, int pos) WARN_UNUSED;
int isl_tab_pivot(struct isl_tab *tab, int row, int col) WARN_UNUSED;
int isl_tab_add_row(struct isl_tab *tab, isl_int *line) WARN_UNUSED;
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_sign_of_max(struct isl_tab *tab, int con);
int isl_tab_kill_col(struct isl_tab *tab, int col) WARN_UNUSED;

isl_stat isl_tab_push(struct isl_tab *tab, enum isl_tab_undo_type type)
	WARN_UNUSED;
isl_stat isl_tab_push_var(struct isl_tab *tab,
	enum isl_tab_undo_type type, struct isl_tab_var *var) WARN_UNUSED;
isl_stat isl_tab_push_basis(struct isl_tab *tab) WARN_UNUSED;

struct isl_tab *isl_tab_init_samples(struct isl_tab *tab) WARN_UNUSED;
int isl_tab_add_sample(struct isl_tab *tab,
	__isl_take isl_vec *sample) WARN_UNUSED;
struct isl_tab *isl_tab_drop_sample(struct isl_tab *tab, int s);
isl_stat isl_tab_save_samples(struct isl_tab *tab) WARN_UNUSED;

struct isl_tab *isl_tab_detect_equalities(struct isl_tab *tab,
	struct isl_tab *tab_cone) WARN_UNUSED;
isl_bool isl_tab_is_constant(struct isl_tab *tab, int var, isl_int *value);
isl_stat isl_tab_detect_constants(struct isl_tab *tab);

isl_stat isl_tab_push_callback(struct isl_tab *tab,
	struct isl_tab_callback *callback) WARN_UNUSED;

int isl_tab_insert_div(struct isl_tab *tab, int pos, __isl_keep isl_vec *div,
	isl_stat (*add_ineq)(void *user, isl_int *), void *user);
int isl_tab_add_div(struct isl_tab *tab, __isl_keep isl_vec *div);

int isl_tab_shift_var(struct isl_tab *tab, int pos, isl_int shift) WARN_UNUSED;

#endif