Bug Summary

File:tools/polly/lib/External/isl/isl_affine_hull.c
Warning:line 491, column 6
Access to field 'sample' results in a dereference of a null pointer (loaded from variable 'bset')

Annotated Source Code

1/*
2 * Copyright 2008-2009 Katholieke Universiteit Leuven
3 * Copyright 2010 INRIA Saclay
4 * Copyright 2012 Ecole Normale Superieure
5 *
6 * Use of this software is governed by the MIT license
7 *
8 * Written by Sven Verdoolaege, K.U.Leuven, Departement
9 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
10 * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
11 * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France
12 * and Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
13 */
14
15#include <isl_ctx_private.h>
16#include <isl_map_private.h>
17#include <isl_seq.h>
18#include <isl/set.h>
19#include <isl/lp.h>
20#include <isl/map.h>
21#include "isl_equalities.h"
22#include "isl_sample.h"
23#include "isl_tab.h"
24#include <isl_mat_private.h>
25#include <isl_vec_private.h>
26
27#include <bset_to_bmap.c>
28#include <bset_from_bmap.c>
29#include <set_to_map.c>
30#include <set_from_map.c>
31
32__isl_give isl_basic_map *isl_basic_map_implicit_equalities(
33 __isl_take isl_basic_map *bmap)
34{
35 struct isl_tab *tab;
36
37 if (!bmap)
38 return bmap;
39
40 bmap = isl_basic_map_gauss(bmap, NULL((void*)0));
41 if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY)(!!(((bmap)->flags) & ((1 << 1)))))
42 return bmap;
43 if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_NO_IMPLICIT)(!!(((bmap)->flags) & ((1 << 2)))))
44 return bmap;
45 if (bmap->n_ineq <= 1)
46 return bmap;
47
48 tab = isl_tab_from_basic_map(bmap, 0);
49 if (isl_tab_detect_implicit_equalities(tab) < 0)
50 goto error;
51 bmap = isl_basic_map_update_from_tab(bmap, tab);
52 isl_tab_free(tab);
53 bmap = isl_basic_map_gauss(bmap, NULL((void*)0));
54 ISL_F_SET(bmap, ISL_BASIC_MAP_NO_IMPLICIT)(((bmap)->flags) |= ((1 << 2)));
55 return bmap;
56error:
57 isl_tab_free(tab);
58 isl_basic_map_free(bmap);
59 return NULL((void*)0);
60}
61
62struct isl_basic_setisl_basic_map *isl_basic_set_implicit_equalities(
63 struct isl_basic_setisl_basic_map *bset)
64{
65 return bset_from_bmap(
66 isl_basic_map_implicit_equalities(bset_to_bmap(bset)));
67}
68
69/* Make eq[row][col] of both bmaps equal so we can add the row
70 * add the column to the common matrix.
71 * Note that because of the echelon form, the columns of row row
72 * after column col are zero.
73 */
74static void set_common_multiple(
75 struct isl_basic_setisl_basic_map *bset1, struct isl_basic_setisl_basic_map *bset2,
76 unsigned row, unsigned col)
77{
78 isl_int m, c;
79
80 if (isl_int_eq(bset1->eq[row][col], bset2->eq[row][col])(isl_sioimath_cmp(*(bset1->eq[row][col]), *(bset2->eq[row
][col])) == 0)
)
81 return;
82
83 isl_int_init(c)isl_sioimath_init((c));
84 isl_int_init(m)isl_sioimath_init((m));
85 isl_int_lcm(m, bset1->eq[row][col], bset2->eq[row][col])isl_sioimath_lcm((m), *(bset1->eq[row][col]), *(bset2->
eq[row][col]))
;
86 isl_int_divexact(c, m, bset1->eq[row][col])isl_sioimath_tdiv_q((c), *(m), *(bset1->eq[row][col]));
87 isl_seq_scale(bset1->eq[row], bset1->eq[row], c, col+1);
88 isl_int_divexact(c, m, bset2->eq[row][col])isl_sioimath_tdiv_q((c), *(m), *(bset2->eq[row][col]));
89 isl_seq_scale(bset2->eq[row], bset2->eq[row], c, col+1);
90 isl_int_clear(c)isl_sioimath_clear((c));
91 isl_int_clear(m)isl_sioimath_clear((m));
92}
93
94/* Delete a given equality, moving all the following equalities one up.
95 */
96static void delete_row(struct isl_basic_setisl_basic_map *bset, unsigned row)
97{
98 isl_int *t;
99 int r;
100
101 t = bset->eq[row];
102 bset->n_eq--;
103 for (r = row; r < bset->n_eq; ++r)
104 bset->eq[r] = bset->eq[r+1];
105 bset->eq[bset->n_eq] = t;
106}
107
108/* Make first row entries in column col of bset1 identical to
109 * those of bset2, using the fact that entry bset1->eq[row][col]=a
110 * is non-zero. Initially, these elements of bset1 are all zero.
111 * For each row i < row, we set
112 * A[i] = a * A[i] + B[i][col] * A[row]
113 * B[i] = a * B[i]
114 * so that
115 * A[i][col] = B[i][col] = a * old(B[i][col])
116 */
117static void construct_column(
118 struct isl_basic_setisl_basic_map *bset1, struct isl_basic_setisl_basic_map *bset2,
119 unsigned row, unsigned col)
120{
121 int r;
122 isl_int a;
123 isl_int b;
124 unsigned total;
125
126 isl_int_init(a)isl_sioimath_init((a));
127 isl_int_init(b)isl_sioimath_init((b));
128 total = 1 + isl_basic_set_n_dim(bset1);
129 for (r = 0; r < row; ++r) {
130 if (isl_int_is_zero(bset2->eq[r][col])(isl_sioimath_sgn(*(bset2->eq[r][col])) == 0))
131 continue;
132 isl_int_gcd(b, bset2->eq[r][col], bset1->eq[row][col])isl_sioimath_gcd((b), *(bset2->eq[r][col]), *(bset1->eq
[row][col]))
;
133 isl_int_divexact(a, bset1->eq[row][col], b)isl_sioimath_tdiv_q((a), *(bset1->eq[row][col]), *(b));
134 isl_int_divexact(b, bset2->eq[r][col], b)isl_sioimath_tdiv_q((b), *(bset2->eq[r][col]), *(b));
135 isl_seq_combine(bset1->eq[r], a, bset1->eq[r],
136 b, bset1->eq[row], total);
137 isl_seq_scale(bset2->eq[r], bset2->eq[r], a, total);
138 }
139 isl_int_clear(a)isl_sioimath_clear((a));
140 isl_int_clear(b)isl_sioimath_clear((b));
141 delete_row(bset1, row);
142}
143
144/* Make first row entries in column col of bset1 identical to
145 * those of bset2, using only these entries of the two matrices.
146 * Let t be the last row with different entries.
147 * For each row i < t, we set
148 * A[i] = (A[t][col]-B[t][col]) * A[i] + (B[i][col]-A[i][col) * A[t]
149 * B[i] = (A[t][col]-B[t][col]) * B[i] + (B[i][col]-A[i][col) * B[t]
150 * so that
151 * A[i][col] = B[i][col] = old(A[t][col]*B[i][col]-A[i][col]*B[t][col])
152 */
153static int transform_column(
154 struct isl_basic_setisl_basic_map *bset1, struct isl_basic_setisl_basic_map *bset2,
155 unsigned row, unsigned col)
156{
157 int i, t;
158 isl_int a, b, g;
159 unsigned total;
160
161 for (t = row-1; t >= 0; --t)
162 if (isl_int_ne(bset1->eq[t][col], bset2->eq[t][col])(isl_sioimath_cmp(*(bset1->eq[t][col]), *(bset2->eq[t][
col])) != 0)
)
163 break;
164 if (t < 0)
165 return 0;
166
167 total = 1 + isl_basic_set_n_dim(bset1);
168 isl_int_init(a)isl_sioimath_init((a));
169 isl_int_init(b)isl_sioimath_init((b));
170 isl_int_init(g)isl_sioimath_init((g));
171 isl_int_sub(b, bset1->eq[t][col], bset2->eq[t][col])isl_sioimath_sub((b), *(bset1->eq[t][col]), *(bset2->eq
[t][col]))
;
172 for (i = 0; i < t; ++i) {
173 isl_int_sub(a, bset2->eq[i][col], bset1->eq[i][col])isl_sioimath_sub((a), *(bset2->eq[i][col]), *(bset1->eq
[i][col]))
;
174 isl_int_gcd(g, a, b)isl_sioimath_gcd((g), *(a), *(b));
175 isl_int_divexact(a, a, g)isl_sioimath_tdiv_q((a), *(a), *(g));
176 isl_int_divexact(g, b, g)isl_sioimath_tdiv_q((g), *(b), *(g));
177 isl_seq_combine(bset1->eq[i], g, bset1->eq[i], a, bset1->eq[t],
178 total);
179 isl_seq_combine(bset2->eq[i], g, bset2->eq[i], a, bset2->eq[t],
180 total);
181 }
182 isl_int_clear(a)isl_sioimath_clear((a));
183 isl_int_clear(b)isl_sioimath_clear((b));
184 isl_int_clear(g)isl_sioimath_clear((g));
185 delete_row(bset1, t);
186 delete_row(bset2, t);
187 return 1;
188}
189
190/* The implementation is based on Section 5.2 of Michael Karr,
191 * "Affine Relationships Among Variables of a Program",
192 * except that the echelon form we use starts from the last column
193 * and that we are dealing with integer coefficients.
194 */
195static struct isl_basic_setisl_basic_map *affine_hull(
196 struct isl_basic_setisl_basic_map *bset1, struct isl_basic_setisl_basic_map *bset2)
197{
198 unsigned total;
199 int col;
200 int row;
201
202 if (!bset1 || !bset2)
203 goto error;
204
205 total = 1 + isl_basic_set_n_dim(bset1);
206
207 row = 0;
208 for (col = total-1; col >= 0; --col) {
209 int is_zero1 = row >= bset1->n_eq ||
210 isl_int_is_zero(bset1->eq[row][col])(isl_sioimath_sgn(*(bset1->eq[row][col])) == 0);
211 int is_zero2 = row >= bset2->n_eq ||
212 isl_int_is_zero(bset2->eq[row][col])(isl_sioimath_sgn(*(bset2->eq[row][col])) == 0);
213 if (!is_zero1 && !is_zero2) {
214 set_common_multiple(bset1, bset2, row, col);
215 ++row;
216 } else if (!is_zero1 && is_zero2) {
217 construct_column(bset1, bset2, row, col);
218 } else if (is_zero1 && !is_zero2) {
219 construct_column(bset2, bset1, row, col);
220 } else {
221 if (transform_column(bset1, bset2, row, col))
222 --row;
223 }
224 }
225 isl_assert(bset1->ctx, row == bset1->n_eq, goto error)do { if (row == bset1->n_eq) break; do { isl_handle_error(
bset1->ctx, isl_error_unknown, "Assertion \"" "row == bset1->n_eq"
"\" failed", "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 225); goto error; } while (0); } while (0)
;
226 isl_basic_set_free(bset2);
227 bset1 = isl_basic_set_normalize_constraints(bset1);
228 return bset1;
229error:
230 isl_basic_set_free(bset1);
231 isl_basic_set_free(bset2);
232 return NULL((void*)0);
233}
234
235/* Find an integer point in the set represented by "tab"
236 * that lies outside of the equality "eq" e(x) = 0.
237 * If "up" is true, look for a point satisfying e(x) - 1 >= 0.
238 * Otherwise, look for a point satisfying -e(x) - 1 >= 0 (i.e., e(x) <= -1).
239 * The point, if found, is returned.
240 * If no point can be found, a zero-length vector is returned.
241 *
242 * Before solving an ILP problem, we first check if simply
243 * adding the normal of the constraint to one of the known
244 * integer points in the basic set represented by "tab"
245 * yields another point inside the basic set.
246 *
247 * The caller of this function ensures that the tableau is bounded or
248 * that tab->basis and tab->n_unbounded have been set appropriately.
249 */
250static struct isl_vec *outside_point(struct isl_tab *tab, isl_int *eq, int up)
251{
252 struct isl_ctx *ctx;
253 struct isl_vec *sample = NULL((void*)0);
254 struct isl_tab_undo *snap;
255 unsigned dim;
256
257 if (!tab)
258 return NULL((void*)0);
259 ctx = tab->mat->ctx;
260
261 dim = tab->n_var;
262 sample = isl_vec_alloc(ctx, 1 + dim);
263 if (!sample)
264 return NULL((void*)0);
265 isl_int_set_si(sample->el[0], 1)isl_sioimath_set_si((sample->el[0]), 1);
266 isl_seq_combine(sample->el + 1,
267 ctx->one, tab->bmap->sample->el + 1,
268 up ? ctx->one : ctx->negone, eq + 1, dim);
269 if (isl_basic_map_contains(tab->bmap, sample))
270 return sample;
271 isl_vec_free(sample);
272 sample = NULL((void*)0);
273
274 snap = isl_tab_snap(tab);
275
276 if (!up)
277 isl_seq_neg(eq, eq, 1 + dim);
278 isl_int_sub_ui(eq[0], eq[0], 1)isl_sioimath_sub_ui((eq[0]), *(eq[0]), 1);
279
280 if (isl_tab_extend_cons(tab, 1) < 0)
281 goto error;
282 if (isl_tab_add_ineq(tab, eq) < 0)
283 goto error;
284
285 sample = isl_tab_sample(tab);
286
287 isl_int_add_ui(eq[0], eq[0], 1)isl_sioimath_add_ui((eq[0]), *(eq[0]), 1);
288 if (!up)
289 isl_seq_neg(eq, eq, 1 + dim);
290
291 if (sample && isl_tab_rollback(tab, snap) < 0)
292 goto error;
293
294 return sample;
295error:
296 isl_vec_free(sample);
297 return NULL((void*)0);
298}
299
300__isl_give isl_basic_setisl_basic_map *isl_basic_set_recession_cone(
301 __isl_take isl_basic_setisl_basic_map *bset)
302{
303 int i;
304
305 bset = isl_basic_set_cow(bset);
306 if (!bset)
307 return NULL((void*)0);
308 isl_assert(bset->ctx, bset->n_div == 0, goto error)do { if (bset->n_div == 0) break; do { isl_handle_error(bset
->ctx, isl_error_unknown, "Assertion \"" "bset->n_div == 0"
"\" failed", "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 308); goto error; } while (0); } while (0)
;
309
310 for (i = 0; i < bset->n_eq; ++i)
311 isl_int_set_si(bset->eq[i][0], 0)isl_sioimath_set_si((bset->eq[i][0]), 0);
312
313 for (i = 0; i < bset->n_ineq; ++i)
314 isl_int_set_si(bset->ineq[i][0], 0)isl_sioimath_set_si((bset->ineq[i][0]), 0);
315
316 ISL_F_CLR(bset, ISL_BASIC_SET_NO_IMPLICIT)(((bset)->flags) &= ~((1 << 2)));
317 return isl_basic_set_implicit_equalities(bset);
318error:
319 isl_basic_set_free(bset);
320 return NULL((void*)0);
321}
322
323/* Move "sample" to a point that is one up (or down) from the original
324 * point in dimension "pos".
325 */
326static void adjacent_point(__isl_keep isl_vec *sample, int pos, int up)
327{
328 if (up)
329 isl_int_add_ui(sample->el[1 + pos], sample->el[1 + pos], 1)isl_sioimath_add_ui((sample->el[1 + pos]), *(sample->el
[1 + pos]), 1)
;
330 else
331 isl_int_sub_ui(sample->el[1 + pos], sample->el[1 + pos], 1)isl_sioimath_sub_ui((sample->el[1 + pos]), *(sample->el
[1 + pos]), 1)
;
332}
333
334/* Check if any points that are adjacent to "sample" also belong to "bset".
335 * If so, add them to "hull" and return the updated hull.
336 *
337 * Before checking whether and adjacent point belongs to "bset", we first
338 * check whether it already belongs to "hull" as this test is typically
339 * much cheaper.
340 */
341static __isl_give isl_basic_setisl_basic_map *add_adjacent_points(
342 __isl_take isl_basic_setisl_basic_map *hull, __isl_take isl_vec *sample,
343 __isl_keep isl_basic_setisl_basic_map *bset)
344{
345 int i, up;
346 int dim;
347
348 if (!sample)
349 goto error;
350
351 dim = isl_basic_set_dim(hull, isl_dim_set);
352
353 for (i = 0; i < dim; ++i) {
354 for (up = 0; up <= 1; ++up) {
355 int contains;
356 isl_basic_setisl_basic_map *point;
357
358 adjacent_point(sample, i, up);
359 contains = isl_basic_set_contains(hull, sample);
360 if (contains < 0)
361 goto error;
362 if (contains) {
363 adjacent_point(sample, i, !up);
364 continue;
365 }
366 contains = isl_basic_set_contains(bset, sample);
367 if (contains < 0)
368 goto error;
369 if (contains) {
370 point = isl_basic_set_from_vec(
371 isl_vec_copy(sample));
372 hull = affine_hull(hull, point);
373 }
374 adjacent_point(sample, i, !up);
375 if (contains)
376 break;
377 }
378 }
379
380 isl_vec_free(sample);
381
382 return hull;
383error:
384 isl_vec_free(sample);
385 isl_basic_set_free(hull);
386 return NULL((void*)0);
387}
388
389/* Extend an initial (under-)approximation of the affine hull of basic
390 * set represented by the tableau "tab"
391 * by looking for points that do not satisfy one of the equalities
392 * in the current approximation and adding them to that approximation
393 * until no such points can be found any more.
394 *
395 * The caller of this function ensures that "tab" is bounded or
396 * that tab->basis and tab->n_unbounded have been set appropriately.
397 *
398 * "bset" may be either NULL or the basic set represented by "tab".
399 * If "bset" is not NULL, we check for any point we find if any
400 * of its adjacent points also belong to "bset".
401 */
402static __isl_give isl_basic_setisl_basic_map *extend_affine_hull(struct isl_tab *tab,
403 __isl_take isl_basic_setisl_basic_map *hull, __isl_keep isl_basic_setisl_basic_map *bset)
404{
405 int i, j;
406 unsigned dim;
407
408 if (!tab || !hull)
409 goto error;
410
411 dim = tab->n_var;
412
413 if (isl_tab_extend_cons(tab, 2 * dim + 1) < 0)
414 goto error;
415
416 for (i = 0; i < dim; ++i) {
417 struct isl_vec *sample;
418 struct isl_basic_setisl_basic_map *point;
419 for (j = 0; j < hull->n_eq; ++j) {
420 sample = outside_point(tab, hull->eq[j], 1);
421 if (!sample)
422 goto error;
423 if (sample->size > 0)
424 break;
425 isl_vec_free(sample);
426 sample = outside_point(tab, hull->eq[j], 0);
427 if (!sample)
428 goto error;
429 if (sample->size > 0)
430 break;
431 isl_vec_free(sample);
432
433 if (isl_tab_add_eq(tab, hull->eq[j]) < 0)
434 goto error;
435 }
436 if (j == hull->n_eq)
437 break;
438 if (tab->samples &&
439 isl_tab_add_sample(tab, isl_vec_copy(sample)) < 0)
440 hull = isl_basic_set_free(hull);
441 if (bset)
442 hull = add_adjacent_points(hull, isl_vec_copy(sample),
443 bset);
444 point = isl_basic_set_from_vec(sample);
445 hull = affine_hull(hull, point);
446 if (!hull)
447 return NULL((void*)0);
448 }
449
450 return hull;
451error:
452 isl_basic_set_free(hull);
453 return NULL((void*)0);
454}
455
456/* Construct an initial underapproximation of the hull of "bset"
457 * from "sample" and any of its adjacent points that also belong to "bset".
458 */
459static __isl_give isl_basic_setisl_basic_map *initialize_hull(__isl_keep isl_basic_setisl_basic_map *bset,
460 __isl_take isl_vec *sample)
461{
462 isl_basic_setisl_basic_map *hull;
463
464 hull = isl_basic_set_from_vec(isl_vec_copy(sample));
465 hull = add_adjacent_points(hull, sample, bset);
466
467 return hull;
468}
469
470/* Look for all equalities satisfied by the integer points in bset,
471 * which is assumed to be bounded.
472 *
473 * The equalities are obtained by successively looking for
474 * a point that is affinely independent of the points found so far.
475 * In particular, for each equality satisfied by the points so far,
476 * we check if there is any point on a hyperplane parallel to the
477 * corresponding hyperplane shifted by at least one (in either direction).
478 */
479static struct isl_basic_setisl_basic_map *uset_affine_hull_bounded(struct isl_basic_setisl_basic_map *bset)
480{
481 struct isl_vec *sample = NULL((void*)0);
482 struct isl_basic_setisl_basic_map *hull;
483 struct isl_tab *tab = NULL((void*)0);
484 unsigned dim;
485
486 if (isl_basic_set_plain_is_empty(bset))
33
Assuming the condition is false
34
Taking false branch
487 return bset;
488
489 dim = isl_basic_set_n_dim(bset);
490
491 if (bset->sample && bset->sample->size == 1 + dim) {
35
Access to field 'sample' results in a dereference of a null pointer (loaded from variable 'bset')
492 int contains = isl_basic_set_contains(bset, bset->sample);
493 if (contains < 0)
494 goto error;
495 if (contains) {
496 if (dim == 0)
497 return bset;
498 sample = isl_vec_copy(bset->sample);
499 } else {
500 isl_vec_free(bset->sample);
501 bset->sample = NULL((void*)0);
502 }
503 }
504
505 tab = isl_tab_from_basic_set(bset, 1);
506 if (!tab)
507 goto error;
508 if (tab->empty) {
509 isl_tab_free(tab);
510 isl_vec_free(sample);
511 return isl_basic_set_set_to_empty(bset);
512 }
513
514 if (!sample) {
515 struct isl_tab_undo *snap;
516 snap = isl_tab_snap(tab);
517 sample = isl_tab_sample(tab);
518 if (isl_tab_rollback(tab, snap) < 0)
519 goto error;
520 isl_vec_free(tab->bmap->sample);
521 tab->bmap->sample = isl_vec_copy(sample);
522 }
523
524 if (!sample)
525 goto error;
526 if (sample->size == 0) {
527 isl_tab_free(tab);
528 isl_vec_free(sample);
529 return isl_basic_set_set_to_empty(bset);
530 }
531
532 hull = initialize_hull(bset, sample);
533
534 hull = extend_affine_hull(tab, hull, bset);
535 isl_basic_set_free(bset);
536 isl_tab_free(tab);
537
538 return hull;
539error:
540 isl_vec_free(sample);
541 isl_tab_free(tab);
542 isl_basic_set_free(bset);
543 return NULL((void*)0);
544}
545
546/* Given an unbounded tableau and an integer point satisfying the tableau,
547 * construct an initial affine hull containing the recession cone
548 * shifted to the given point.
549 *
550 * The unbounded directions are taken from the last rows of the basis,
551 * which is assumed to have been initialized appropriately.
552 */
553static __isl_give isl_basic_setisl_basic_map *initial_hull(struct isl_tab *tab,
554 __isl_take isl_vec *vec)
555{
556 int i;
557 int k;
558 struct isl_basic_setisl_basic_map *bset = NULL((void*)0);
559 struct isl_ctx *ctx;
560 unsigned dim;
561
562 if (!vec || !tab)
563 return NULL((void*)0);
564 ctx = vec->ctx;
565 isl_assert(ctx, vec->size != 0, goto error)do { if (vec->size != 0) break; do { isl_handle_error(ctx,
isl_error_unknown, "Assertion \"" "vec->size != 0" "\" failed"
, "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 565); goto error; } while (0); } while (0)
;
566
567 bset = isl_basic_set_alloc(ctx, 0, vec->size - 1, 0, vec->size - 1, 0);
568 if (!bset)
569 goto error;
570 dim = isl_basic_set_n_dim(bset) - tab->n_unbounded;
571 for (i = 0; i < dim; ++i) {
572 k = isl_basic_set_alloc_equality(bset);
573 if (k < 0)
574 goto error;
575 isl_seq_cpy(bset->eq[k] + 1, tab->basis->row[1 + i] + 1,
576 vec->size - 1);
577 isl_seq_inner_product(bset->eq[k] + 1, vec->el +1,
578 vec->size - 1, &bset->eq[k][0]);
579 isl_int_neg(bset->eq[k][0], bset->eq[k][0])isl_sioimath_neg((bset->eq[k][0]), *(bset->eq[k][0]));
580 }
581 bset->sample = vec;
582 bset = isl_basic_set_gauss(bset, NULL((void*)0));
583
584 return bset;
585error:
586 isl_basic_set_free(bset);
587 isl_vec_free(vec);
588 return NULL((void*)0);
589}
590
591/* Given a tableau of a set and a tableau of the corresponding
592 * recession cone, detect and add all equalities to the tableau.
593 * If the tableau is bounded, then we can simply keep the
594 * tableau in its state after the return from extend_affine_hull.
595 * However, if the tableau is unbounded, then
596 * isl_tab_set_initial_basis_with_cone will add some additional
597 * constraints to the tableau that have to be removed again.
598 * In this case, we therefore rollback to the state before
599 * any constraints were added and then add the equalities back in.
600 */
601struct isl_tab *isl_tab_detect_equalities(struct isl_tab *tab,
602 struct isl_tab *tab_cone)
603{
604 int j;
605 struct isl_vec *sample;
606 struct isl_basic_setisl_basic_map *hull = NULL((void*)0);
607 struct isl_tab_undo *snap;
608
609 if (!tab || !tab_cone)
610 goto error;
611
612 snap = isl_tab_snap(tab);
613
614 isl_mat_free(tab->basis);
615 tab->basis = NULL((void*)0);
616
617 isl_assert(tab->mat->ctx, tab->bmap, goto error)do { if (tab->bmap) break; do { isl_handle_error(tab->mat
->ctx, isl_error_unknown, "Assertion \"" "tab->bmap" "\" failed"
, "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 617); goto error; } while (0); } while (0)
;
618 isl_assert(tab->mat->ctx, tab->samples, goto error)do { if (tab->samples) break; do { isl_handle_error(tab->
mat->ctx, isl_error_unknown, "Assertion \"" "tab->samples"
"\" failed", "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 618); goto error; } while (0); } while (0)
;
619 isl_assert(tab->mat->ctx, tab->samples->n_col == 1 + tab->n_var, goto error)do { if (tab->samples->n_col == 1 + tab->n_var) break
; do { isl_handle_error(tab->mat->ctx, isl_error_unknown
, "Assertion \"" "tab->samples->n_col == 1 + tab->n_var"
"\" failed", "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 619); goto error; } while (0); } while (0)
;
620 isl_assert(tab->mat->ctx, tab->n_sample > tab->n_outside, goto error)do { if (tab->n_sample > tab->n_outside) break; do {
isl_handle_error(tab->mat->ctx, isl_error_unknown, "Assertion \""
"tab->n_sample > tab->n_outside" "\" failed", "/tmp/buildd/llvm-toolchain-snapshot-5.0~svn306458/tools/polly/lib/External/isl/isl_affine_hull.c"
, 620); goto error; } while (0); } while (0)
;
621
622 if (isl_tab_set_initial_basis_with_cone(tab, tab_cone) < 0)
623 goto error;
624
625 sample = isl_vec_alloc(tab->mat->ctx, 1 + tab->n_var);
626 if (!sample)
627 goto error;
628
629 isl_seq_cpy(sample->el, tab->samples->row[tab->n_outside], sample->size);
630
631 isl_vec_free(tab->bmap->sample);
632 tab->bmap->sample = isl_vec_copy(sample);
633
634 if (tab->n_unbounded == 0)
635 hull = isl_basic_set_from_vec(isl_vec_copy(sample));
636 else
637 hull = initial_hull(tab, isl_vec_copy(sample));
638
639 for (j = tab->n_outside + 1; j < tab->n_sample; ++j) {
640 isl_seq_cpy(sample->el, tab->samples->row[j], sample->size);
641 hull = affine_hull(hull,
642 isl_basic_set_from_vec(isl_vec_copy(sample)));
643 }
644
645 isl_vec_free(sample);
646
647 hull = extend_affine_hull(tab, hull, NULL((void*)0));
648 if (!hull)
649 goto error;
650
651 if (tab->n_unbounded == 0) {
652 isl_basic_set_free(hull);
653 return tab;
654 }
655
656 if (isl_tab_rollback(tab, snap) < 0)
657 goto error;
658
659 if (hull->n_eq > tab->n_zero) {
660 for (j = 0; j < hull->n_eq; ++j) {
661 isl_seq_normalize(tab->mat->ctx, hull->eq[j], 1 + tab->n_var);
662 if (isl_tab_add_eq(tab, hull->eq[j]) < 0)
663 goto error;
664 }
665 }
666
667 isl_basic_set_free(hull);
668
669 return tab;
670error:
671 isl_basic_set_free(hull);
672 isl_tab_free(tab);
673 return NULL((void*)0);
674}
675
676/* Compute the affine hull of "bset", where "cone" is the recession cone
677 * of "bset".
678 *
679 * We first compute a unimodular transformation that puts the unbounded
680 * directions in the last dimensions. In particular, we take a transformation
681 * that maps all equalities to equalities (in HNF) on the first dimensions.
682 * Let x be the original dimensions and y the transformed, with y_1 bounded
683 * and y_2 unbounded.
684 *
685 * [ y_1 ] [ y_1 ] [ Q_1 ]
686 * x = U [ y_2 ] [ y_2 ] = [ Q_2 ] x
687 *
688 * Let's call the input basic set S. We compute S' = preimage(S, U)
689 * and drop the final dimensions including any constraints involving them.
690 * This results in set S''.
691 * Then we compute the affine hull A'' of S''.
692 * Let F y_1 >= g be the constraint system of A''. In the transformed
693 * space the y_2 are unbounded, so we can add them back without any constraints,
694 * resulting in
695 *
696 * [ y_1 ]
697 * [ F 0 ] [ y_2 ] >= g
698 * or
699 * [ Q_1 ]
700 * [ F 0 ] [ Q_2 ] x >= g
701 * or
702 * F Q_1 x >= g
703 *
704 * The affine hull in the original space is then obtained as
705 * A = preimage(A'', Q_1).
706 */
707static struct isl_basic_setisl_basic_map *affine_hull_with_cone(struct isl_basic_setisl_basic_map *bset,
708 struct isl_basic_setisl_basic_map *cone)
709{
710 unsigned total;
711 unsigned cone_dim;
712 struct isl_basic_setisl_basic_map *hull;
713 struct isl_mat *M, *U, *Q;
714
715 if (!bset || !cone)
25
Taking false branch
716 goto error;
717
718 total = isl_basic_set_total_dim(cone);
719 cone_dim = total - cone->n_eq;
720
721 M = isl_mat_sub_alloc6(bset->ctx, cone->eq, 0, cone->n_eq, 1, total);
722 M = isl_mat_left_hermite(M, 0, &U, &Q);
723 if (!M)
26
Assuming 'M' is non-null
27
Taking false branch
724 goto error;
725 isl_mat_free(M);
726
727 U = isl_mat_lin_to_aff(U);
728 bset = isl_basic_set_preimage(bset, isl_mat_copy(U));
729
730 bset = isl_basic_set_drop_constraints_involving(bset, total - cone_dim,
731 cone_dim);
732 bset = isl_basic_set_drop_dims(bset, total - cone_dim, cone_dim);
28
Value assigned to 'bset'
733
734 Q = isl_mat_lin_to_aff(Q);
735 Q = isl_mat_drop_rows(Q, 1 + total - cone_dim, cone_dim);
736
737 if (bset && bset->sample && bset->sample->size == 1 + total)
29
Assuming pointer value is null
30
Assuming 'bset' is null
738 bset->sample = isl_mat_vec_product(isl_mat_copy(Q), bset->sample);
739
740 hull = uset_affine_hull_bounded(bset);
31
Passing null pointer value via 1st parameter 'bset'
32
Calling 'uset_affine_hull_bounded'
741
742 if (!hull) {
743 isl_mat_free(Q);
744 isl_mat_free(U);
745 } else {
746 struct isl_vec *sample = isl_vec_copy(hull->sample);
747 U = isl_mat_drop_cols(U, 1 + total - cone_dim, cone_dim);
748 if (sample && sample->size > 0)
749 sample = isl_mat_vec_product(U, sample);
750 else
751 isl_mat_free(U);
752 hull = isl_basic_set_preimage(hull, Q);
753 if (hull) {
754 isl_vec_free(hull->sample);
755 hull->sample = sample;
756 } else
757 isl_vec_free(sample);
758 }
759
760 isl_basic_set_free(cone);
761
762 return hull;
763error:
764 isl_basic_set_free(bset);
765 isl_basic_set_free(cone);
766 return NULL((void*)0);
767}
768
769/* Look for all equalities satisfied by the integer points in bset,
770 * which is assumed not to have any explicit equalities.
771 *
772 * The equalities are obtained by successively looking for
773 * a point that is affinely independent of the points found so far.
774 * In particular, for each equality satisfied by the points so far,
775 * we check if there is any point on a hyperplane parallel to the
776 * corresponding hyperplane shifted by at least one (in either direction).
777 *
778 * Before looking for any outside points, we first compute the recession
779 * cone. The directions of this recession cone will always be part
780 * of the affine hull, so there is no need for looking for any points
781 * in these directions.
782 * In particular, if the recession cone is full-dimensional, then
783 * the affine hull is simply the whole universe.
784 */
785static struct isl_basic_setisl_basic_map *uset_affine_hull(struct isl_basic_setisl_basic_map *bset)
786{
787 struct isl_basic_setisl_basic_map *cone;
788
789 if (isl_basic_set_plain_is_empty(bset))
17
Assuming the condition is false
18
Taking false branch
790 return bset;
791
792 cone = isl_basic_set_recession_cone(isl_basic_set_copy(bset));
793 if (!cone)
19
Assuming 'cone' is non-null
20
Taking false branch
794 goto error;
795 if (cone->n_eq == 0) {
21
Assuming the condition is false
22
Taking false branch
796 isl_space *space;
797 space = isl_basic_set_get_space(bset);
798 isl_basic_set_free(cone);
799 isl_basic_set_free(bset);
800 return isl_basic_set_universe(space);
801 }
802
803 if (cone->n_eq < isl_basic_set_total_dim(cone))
23
Taking true branch
804 return affine_hull_with_cone(bset, cone);
24
Calling 'affine_hull_with_cone'
805
806 isl_basic_set_free(cone);
807 return uset_affine_hull_bounded(bset);
808error:
809 isl_basic_set_free(bset);
810 return NULL((void*)0);
811}
812
813/* Look for all equalities satisfied by the integer points in bmap
814 * that are independent of the equalities already explicitly available
815 * in bmap.
816 *
817 * We first remove all equalities already explicitly available,
818 * then look for additional equalities in the reduced space
819 * and then transform the result to the original space.
820 * The original equalities are _not_ added to this set. This is
821 * the responsibility of the calling function.
822 * The resulting basic set has all meaning about the dimensions removed.
823 * In particular, dimensions that correspond to existential variables
824 * in bmap and that are found to be fixed are not removed.
825 */
826static struct isl_basic_setisl_basic_map *equalities_in_underlying_set(
827 struct isl_basic_map *bmap)
828{
829 struct isl_mat *T1 = NULL((void*)0);
830 struct isl_mat *T2 = NULL((void*)0);
831 struct isl_basic_setisl_basic_map *bset = NULL((void*)0);
832 struct isl_basic_setisl_basic_map *hull = NULL((void*)0);
833
834 bset = isl_basic_map_underlying_set(bmap);
835 if (!bset)
11
Assuming 'bset' is non-null
12
Taking false branch
836 return NULL((void*)0);
837 if (bset->n_eq)
13
Assuming the condition is false
14
Taking false branch
838 bset = isl_basic_set_remove_equalities(bset, &T1, &T2);
839 if (!bset)
15
Taking false branch
840 goto error;
841
842 hull = uset_affine_hull(bset);
16
Calling 'uset_affine_hull'
843 if (!T2)
844 return hull;
845
846 if (!hull) {
847 isl_mat_free(T1);
848 isl_mat_free(T2);
849 } else {
850 struct isl_vec *sample = isl_vec_copy(hull->sample);
851 if (sample && sample->size > 0)
852 sample = isl_mat_vec_product(T1, sample);
853 else
854 isl_mat_free(T1);
855 hull = isl_basic_set_preimage(hull, T2);
856 if (hull) {
857 isl_vec_free(hull->sample);
858 hull->sample = sample;
859 } else
860 isl_vec_free(sample);
861 }
862
863 return hull;
864error:
865 isl_mat_free(T1);
866 isl_mat_free(T2);
867 isl_basic_set_free(bset);
868 isl_basic_set_free(hull);
869 return NULL((void*)0);
870}
871
872/* Detect and make explicit all equalities satisfied by the (integer)
873 * points in bmap.
874 */
875__isl_give isl_basic_map *isl_basic_map_detect_equalities(
876 __isl_take isl_basic_map *bmap)
877{
878 int i, j;
879 struct isl_basic_setisl_basic_map *hull = NULL((void*)0);
880
881 if (!bmap)
3
Assuming 'bmap' is non-null
4
Taking false branch
882 return NULL((void*)0);
883 if (bmap->n_ineq == 0)
5
Assuming the condition is false
6
Taking false branch
884 return bmap;
885 if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY)(!!(((bmap)->flags) & ((1 << 1)))))
7
Taking false branch
886 return bmap;
887 if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_ALL_EQUALITIES)(!!(((bmap)->flags) & ((1 << 7)))))
8
Taking false branch
888 return bmap;
889 if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL)(!!(((bmap)->flags) & ((1 << 4)))))
9
Taking false branch
890 return isl_basic_map_implicit_equalities(bmap);
891
892 hull = equalities_in_underlying_set(isl_basic_map_copy(bmap));
10
Calling 'equalities_in_underlying_set'
893 if (!hull)
894 goto error;
895 if (ISL_F_ISSET(hull, ISL_BASIC_SET_EMPTY)(!!(((hull)->flags) & ((1 << 1))))) {
896 isl_basic_set_free(hull);
897 return isl_basic_map_set_to_empty(bmap);
898 }
899 bmap = isl_basic_map_extend_space(bmap, isl_space_copy(bmap->dim), 0,
900 hull->n_eq, 0);
901 for (i = 0; i < hull->n_eq; ++i) {
902 j = isl_basic_map_alloc_equality(bmap);
903 if (j < 0)
904 goto error;
905 isl_seq_cpy(bmap->eq[j], hull->eq[i],
906 1 + isl_basic_set_total_dim(hull));
907 }
908 isl_vec_free(bmap->sample);
909 bmap->sample = isl_vec_copy(hull->sample);
910 isl_basic_set_free(hull);
911 ISL_F_SET(bmap, ISL_BASIC_MAP_NO_IMPLICIT | ISL_BASIC_MAP_ALL_EQUALITIES)(((bmap)->flags) |= ((1 << 2) | (1 << 7)));
912 bmap = isl_basic_map_simplify(bmap);
913 return isl_basic_map_finalize(bmap);
914error:
915 isl_basic_set_free(hull);
916 isl_basic_map_free(bmap);
917 return NULL((void*)0);
918}
919
920__isl_give isl_basic_setisl_basic_map *isl_basic_set_detect_equalities(
921 __isl_take isl_basic_setisl_basic_map *bset)
922{
923 return bset_from_bmap(
924 isl_basic_map_detect_equalities(bset_to_bmap(bset)));
925}
926
927__isl_give isl_map *isl_map_detect_equalities(__isl_take isl_map *map)
928{
929 return isl_map_inline_foreach_basic_map(map,
930 &isl_basic_map_detect_equalities);
931}
932
933__isl_give isl_setisl_map *isl_set_detect_equalities(__isl_take isl_setisl_map *set)
934{
935 return set_from_map(isl_map_detect_equalities(set_to_map(set)));
936}
937
938/* Return the superset of "bmap" described by the equalities
939 * satisfied by "bmap" that are already known.
940 */
941__isl_give isl_basic_map *isl_basic_map_plain_affine_hull(
942 __isl_take isl_basic_map *bmap)
943{
944 bmap = isl_basic_map_cow(bmap);
945 if (bmap)
946 isl_basic_map_free_inequality(bmap, bmap->n_ineq);
947 bmap = isl_basic_map_finalize(bmap);
948 return bmap;
949}
950
951/* Return the superset of "bset" described by the equalities
952 * satisfied by "bset" that are already known.
953 */
954__isl_give isl_basic_setisl_basic_map *isl_basic_set_plain_affine_hull(
955 __isl_take isl_basic_setisl_basic_map *bset)
956{
957 return isl_basic_map_plain_affine_hull(bset);
958}
959
960/* After computing the rational affine hull (by detecting the implicit
961 * equalities), we compute the additional equalities satisfied by
962 * the integer points (if any) and add the original equalities back in.
963 */
964__isl_give isl_basic_map *isl_basic_map_affine_hull(
965 __isl_take isl_basic_map *bmap)
966{
967 bmap = isl_basic_map_detect_equalities(bmap);
2
Calling 'isl_basic_map_detect_equalities'
968 bmap = isl_basic_map_plain_affine_hull(bmap);
969 return bmap;
970}
971
972struct isl_basic_setisl_basic_map *isl_basic_set_affine_hull(struct isl_basic_setisl_basic_map *bset)
973{
974 return bset_from_bmap(isl_basic_map_affine_hull(bset_to_bmap(bset)));
1
Calling 'isl_basic_map_affine_hull'
975}
976
977/* Given a rational affine matrix "M", add stride constraints to "bmap"
978 * that ensure that
979 *
980 * M(x)
981 *
982 * is an integer vector. The variables x include all the variables
983 * of "bmap" except the unknown divs.
984 *
985 * If d is the common denominator of M, then we need to impose that
986 *
987 * d M(x) = 0 mod d
988 *
989 * or
990 *
991 * exists alpha : d M(x) = d alpha
992 *
993 * This function is similar to add_strides in isl_morph.c
994 */
995static __isl_give isl_basic_map *add_strides(__isl_take isl_basic_map *bmap,
996 __isl_keep isl_mat *M, int n_known)
997{
998 int i, div, k;
999 isl_int gcd;
1000
1001 if (isl_int_is_one(M->row[0][0])(isl_sioimath_cmp_si(*(M->row[0][0]), 1) == 0))
1002 return bmap;
1003
1004 bmap = isl_basic_map_extend_space(bmap, isl_space_copy(bmap->dim),
1005 M->n_row - 1, M->n_row - 1, 0);
1006
1007 isl_int_init(gcd)isl_sioimath_init((gcd));
1008 for (i = 1; i < M->n_row; ++i) {
1009 isl_seq_gcd(M->row[i], M->n_col, &gcd);
1010 if (isl_int_is_divisible_by(gcd, M->row[0][0])isl_sioimath_is_divisible_by(*(gcd), *(M->row[0][0])))
1011 continue;
1012 div = isl_basic_map_alloc_div(bmap);
1013 if (div < 0)
1014 goto error;
1015 isl_int_set_si(bmap->div[div][0], 0)isl_sioimath_set_si((bmap->div[div][0]), 0);
1016 k = isl_basic_map_alloc_equality(bmap);
1017 if (k < 0)
1018 goto error;
1019 isl_seq_cpy(bmap->eq[k], M->row[i], M->n_col);
1020 isl_seq_clr(bmap->eq[k] + M->n_col, bmap->n_div - n_known);
1021 isl_int_set(bmap->eq[k][M->n_col - n_known + div],isl_sioimath_set((bmap->eq[k][M->n_col - n_known + div]
), *(M->row[0][0]))
1022 M->row[0][0])isl_sioimath_set((bmap->eq[k][M->n_col - n_known + div]
), *(M->row[0][0]))
;
1023 }
1024 isl_int_clear(gcd)isl_sioimath_clear((gcd));
1025
1026 return bmap;
1027error:
1028 isl_int_clear(gcd)isl_sioimath_clear((gcd));
1029 isl_basic_map_free(bmap);
1030 return NULL((void*)0);
1031}
1032
1033/* If there are any equalities that involve (multiple) unknown divs,
1034 * then extract the stride information encoded by those equalities
1035 * and make it explicitly available in "bmap".
1036 *
1037 * We first sort the divs so that the unknown divs appear last and
1038 * then we count how many equalities involve these divs.
1039 *
1040 * Let these equalities be of the form
1041 *
1042 * A(x) + B y = 0
1043 *
1044 * where y represents the unknown divs and x the remaining variables.
1045 * Let [H 0] be the Hermite Normal Form of B, i.e.,
1046 *
1047 * B = [H 0] Q
1048 *
1049 * Then x is a solution of the equalities iff
1050 *
1051 * H^-1 A(x) (= - [I 0] Q y)
1052 *
1053 * is an integer vector. Let d be the common denominator of H^-1.
1054 * We impose
1055 *
1056 * d H^-1 A(x) = d alpha
1057 *
1058 * in add_strides, with alpha fresh existentially quantified variables.
1059 */
1060static __isl_give isl_basic_map *isl_basic_map_make_strides_explicit(
1061 __isl_take isl_basic_map *bmap)
1062{
1063 int known;
1064 int n_known;
1065 int n, n_col;
1066 int total;
1067 isl_ctx *ctx;
1068 isl_mat *A, *B, *M;
1069
1070 known = isl_basic_map_divs_known(bmap);
1071 if (known < 0)
1072 return isl_basic_map_free(bmap);
1073 if (known)
1074 return bmap;
1075 bmap = isl_basic_map_sort_divs(bmap);
1076 bmap = isl_basic_map_gauss(bmap, NULL((void*)0));
1077 if (!bmap)
1078 return NULL((void*)0);
1079
1080 for (n_known = 0; n_known < bmap->n_div; ++n_known)
1081 if (isl_int_is_zero(bmap->div[n_known][0])(isl_sioimath_sgn(*(bmap->div[n_known][0])) == 0))
1082 break;
1083 ctx = isl_basic_map_get_ctx(bmap);
1084 total = isl_space_dim(bmap->dim, isl_dim_all);
1085 for (n = 0; n < bmap->n_eq; ++n)
1086 if (isl_seq_first_non_zero(bmap->eq[n] + 1 + total + n_known,
1087 bmap->n_div - n_known) == -1)
1088 break;
1089 if (n == 0)
1090 return bmap;
1091 B = isl_mat_sub_alloc6(ctx, bmap->eq, 0, n, 0, 1 + total + n_known);
1092 n_col = bmap->n_div - n_known;
1093 A = isl_mat_sub_alloc6(ctx, bmap->eq, 0, n, 1 + total + n_known, n_col);
1094 A = isl_mat_left_hermite(A, 0, NULL((void*)0), NULL((void*)0));
1095 A = isl_mat_drop_cols(A, n, n_col - n);
1096 A = isl_mat_lin_to_aff(A);
1097 A = isl_mat_right_inverse(A);
1098 B = isl_mat_insert_zero_rows(B, 0, 1);
1099 B = isl_mat_set_element_si(B, 0, 0, 1);
1100 M = isl_mat_product(A, B);
1101 if (!M)
1102 return isl_basic_map_free(bmap);
1103 bmap = add_strides(bmap, M, n_known);
1104 bmap = isl_basic_map_gauss(bmap, NULL((void*)0));
1105 isl_mat_free(M);
1106
1107 return bmap;
1108}
1109
1110/* Compute the affine hull of each basic map in "map" separately
1111 * and make all stride information explicit so that we can remove
1112 * all unknown divs without losing this information.
1113 * The result is also guaranteed to be gaussed.
1114 *
1115 * In simple cases where a div is determined by an equality,
1116 * calling isl_basic_map_gauss is enough to make the stride information
1117 * explicit, as it will derive an explicit representation for the div
1118 * from the equality. If, however, the stride information
1119 * is encoded through multiple unknown divs then we need to make
1120 * some extra effort in isl_basic_map_make_strides_explicit.
1121 */
1122static __isl_give isl_map *isl_map_local_affine_hull(__isl_take isl_map *map)
1123{
1124 int i;
1125
1126 map = isl_map_cow(map);
1127 if (!map)
1128 return NULL((void*)0);
1129
1130 for (i = 0; i < map->n; ++i) {
1131 map->p[i] = isl_basic_map_affine_hull(map->p[i]);
1132 map->p[i] = isl_basic_map_gauss(map->p[i], NULL((void*)0));
1133 map->p[i] = isl_basic_map_make_strides_explicit(map->p[i]);
1134 if (!map->p[i])
1135 return isl_map_free(map);
1136 }
1137
1138 return map;
1139}
1140
1141static __isl_give isl_setisl_map *isl_set_local_affine_hull(__isl_take isl_setisl_map *set)
1142{
1143 return isl_map_local_affine_hull(set);
1144}
1145
1146/* Return an empty basic map living in the same space as "map".
1147 */
1148static __isl_give isl_basic_map *replace_map_by_empty_basic_map(
1149 __isl_take isl_map *map)
1150{
1151 isl_space *space;
1152
1153 space = isl_map_get_space(map);
1154 isl_map_free(map);
1155 return isl_basic_map_empty(space);
1156}
1157
1158/* Compute the affine hull of "map".
1159 *
1160 * We first compute the affine hull of each basic map separately.
1161 * Then we align the divs and recompute the affine hulls of the basic
1162 * maps since some of them may now have extra divs.
1163 * In order to avoid performing parametric integer programming to
1164 * compute explicit expressions for the divs, possible leading to
1165 * an explosion in the number of basic maps, we first drop all unknown
1166 * divs before aligning the divs. Note that isl_map_local_affine_hull tries
1167 * to make sure that all stride information is explicitly available
1168 * in terms of known divs. This involves calling isl_basic_set_gauss,
1169 * which is also needed because affine_hull assumes its input has been gaussed,
1170 * while isl_map_affine_hull may be called on input that has not been gaussed,
1171 * in particular from initial_facet_constraint.
1172 * Similarly, align_divs may reorder some divs so that we need to
1173 * gauss the result again.
1174 * Finally, we combine the individual affine hulls into a single
1175 * affine hull.
1176 */
1177__isl_give isl_basic_map *isl_map_affine_hull(__isl_take isl_map *map)
1178{
1179 struct isl_basic_map *model = NULL((void*)0);
1180 struct isl_basic_map *hull = NULL((void*)0);
1181 struct isl_setisl_map *set;
1182 isl_basic_setisl_basic_map *bset;
1183
1184 map = isl_map_detect_equalities(map);
1185 map = isl_map_local_affine_hull(map);
1186 map = isl_map_remove_empty_parts(map);
1187 map = isl_map_remove_unknown_divs(map);
1188 map = isl_map_align_divs_internal(map);
1189
1190 if (!map)
1191 return NULL((void*)0);
1192
1193 if (map->n == 0)
1194 return replace_map_by_empty_basic_map(map);
1195
1196 model = isl_basic_map_copy(map->p[0]);
1197 set = isl_map_underlying_set(map);
1198 set = isl_set_cow(set);
1199 set = isl_set_local_affine_hull(set);
1200 if (!set)
1201 goto error;
1202
1203 while (set->n > 1)
1204 set->p[0] = affine_hull(set->p[0], set->p[--set->n]);
1205
1206 bset = isl_basic_set_copy(set->p[0]);
1207 hull = isl_basic_map_overlying_set(bset, model);
1208 isl_set_free(set);
1209 hull = isl_basic_map_simplify(hull);
1210 return isl_basic_map_finalize(hull);
1211error:
1212 isl_basic_map_free(model);
1213 isl_set_free(set);
1214 return NULL((void*)0);
1215}
1216
1217struct isl_basic_setisl_basic_map *isl_set_affine_hull(struct isl_setisl_map *set)
1218{
1219 return bset_from_bmap(isl_map_affine_hull(set_to_map(set)));
1220}