1 /*
2 * Copyright 2010-2011 INRIA Saclay
3 * Copyright 2014 Ecole Normale Superieure
4 *
5 * Use of this software is governed by the MIT license
6 *
7 * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
8 * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
9 * 91893 Orsay, France
10 * and Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
11 */
12
13 #include <isl_map_private.h>
14 #include <isl_aff_private.h>
15 #include <isl_morph.h>
16 #include <isl_seq.h>
17 #include <isl_mat_private.h>
18 #include <isl_space_private.h>
19 #include <isl_equalities.h>
20 #include <isl_id_private.h>
21 #include <isl_aff_private.h>
22 #include <isl_vec_private.h>
23
isl_morph_get_ctx(__isl_keep isl_morph * morph)24 isl_ctx *isl_morph_get_ctx(__isl_keep isl_morph *morph)
25 {
26 if (!morph)
27 return NULL;
28 return isl_basic_set_get_ctx(morph->dom);
29 }
30
isl_morph_alloc(__isl_take isl_basic_set * dom,__isl_take isl_basic_set * ran,__isl_take isl_mat * map,__isl_take isl_mat * inv)31 __isl_give isl_morph *isl_morph_alloc(
32 __isl_take isl_basic_set *dom, __isl_take isl_basic_set *ran,
33 __isl_take isl_mat *map, __isl_take isl_mat *inv)
34 {
35 isl_morph *morph;
36
37 if (!dom || !ran || !map || !inv)
38 goto error;
39
40 morph = isl_alloc_type(dom->ctx, struct isl_morph);
41 if (!morph)
42 goto error;
43
44 morph->ref = 1;
45 morph->dom = dom;
46 morph->ran = ran;
47 morph->map = map;
48 morph->inv = inv;
49
50 return morph;
51 error:
52 isl_basic_set_free(dom);
53 isl_basic_set_free(ran);
54 isl_mat_free(map);
55 isl_mat_free(inv);
56 return NULL;
57 }
58
isl_morph_copy(__isl_keep isl_morph * morph)59 __isl_give isl_morph *isl_morph_copy(__isl_keep isl_morph *morph)
60 {
61 if (!morph)
62 return NULL;
63
64 morph->ref++;
65 return morph;
66 }
67
isl_morph_dup(__isl_keep isl_morph * morph)68 __isl_give isl_morph *isl_morph_dup(__isl_keep isl_morph *morph)
69 {
70 if (!morph)
71 return NULL;
72
73 return isl_morph_alloc(isl_basic_set_copy(morph->dom),
74 isl_basic_set_copy(morph->ran),
75 isl_mat_copy(morph->map), isl_mat_copy(morph->inv));
76 }
77
isl_morph_cow(__isl_take isl_morph * morph)78 __isl_give isl_morph *isl_morph_cow(__isl_take isl_morph *morph)
79 {
80 if (!morph)
81 return NULL;
82
83 if (morph->ref == 1)
84 return morph;
85 morph->ref--;
86 return isl_morph_dup(morph);
87 }
88
isl_morph_free(__isl_take isl_morph * morph)89 __isl_null isl_morph *isl_morph_free(__isl_take isl_morph *morph)
90 {
91 if (!morph)
92 return NULL;
93
94 if (--morph->ref > 0)
95 return NULL;
96
97 isl_basic_set_free(morph->dom);
98 isl_basic_set_free(morph->ran);
99 isl_mat_free(morph->map);
100 isl_mat_free(morph->inv);
101 free(morph);
102
103 return NULL;
104 }
105
106 /* Is "morph" an identity on the parameters?
107 */
identity_on_parameters(__isl_keep isl_morph * morph)108 static isl_bool identity_on_parameters(__isl_keep isl_morph *morph)
109 {
110 isl_bool is_identity;
111 isl_size nparam, nparam_ran;
112 isl_mat *sub;
113
114 nparam = isl_morph_dom_dim(morph, isl_dim_param);
115 nparam_ran = isl_morph_ran_dim(morph, isl_dim_param);
116 if (nparam < 0 || nparam_ran < 0)
117 return isl_bool_error;
118 if (nparam != nparam_ran)
119 return isl_bool_false;
120 if (nparam == 0)
121 return isl_bool_true;
122 sub = isl_mat_sub_alloc(morph->map, 0, 1 + nparam, 0, 1 + nparam);
123 is_identity = isl_mat_is_scaled_identity(sub);
124 isl_mat_free(sub);
125
126 return is_identity;
127 }
128
129 /* Return an affine expression of the variables of the range of "morph"
130 * in terms of the parameters and the variables of the domain on "morph".
131 *
132 * In order for the space manipulations to make sense, we require
133 * that the parameters are not modified by "morph".
134 */
isl_morph_get_var_multi_aff(__isl_keep isl_morph * morph)135 __isl_give isl_multi_aff *isl_morph_get_var_multi_aff(
136 __isl_keep isl_morph *morph)
137 {
138 isl_space *dom, *ran, *space;
139 isl_local_space *ls;
140 isl_multi_aff *ma;
141 isl_size nparam, nvar;
142 int i;
143 isl_bool is_identity;
144
145 if (!morph)
146 return NULL;
147
148 is_identity = identity_on_parameters(morph);
149 if (is_identity < 0)
150 return NULL;
151 if (!is_identity)
152 isl_die(isl_morph_get_ctx(morph), isl_error_invalid,
153 "cannot handle parameter compression", return NULL);
154
155 dom = isl_morph_get_dom_space(morph);
156 ls = isl_local_space_from_space(isl_space_copy(dom));
157 ran = isl_morph_get_ran_space(morph);
158 space = isl_space_map_from_domain_and_range(dom, ran);
159 ma = isl_multi_aff_zero(space);
160
161 nparam = isl_multi_aff_dim(ma, isl_dim_param);
162 nvar = isl_multi_aff_dim(ma, isl_dim_out);
163 if (nparam < 0 || nvar < 0)
164 ma = isl_multi_aff_free(ma);
165 for (i = 0; i < nvar; ++i) {
166 isl_val *val;
167 isl_vec *v;
168 isl_aff *aff;
169
170 v = isl_mat_get_row(morph->map, 1 + nparam + i);
171 v = isl_vec_insert_els(v, 0, 1);
172 val = isl_mat_get_element_val(morph->map, 0, 0);
173 v = isl_vec_set_element_val(v, 0, val);
174 aff = isl_aff_alloc_vec(isl_local_space_copy(ls), v);
175 ma = isl_multi_aff_set_aff(ma, i, aff);
176 }
177
178 isl_local_space_free(ls);
179 return ma;
180 }
181
182 /* Return the domain space of "morph".
183 */
isl_morph_peek_dom_space(__isl_keep isl_morph * morph)184 static __isl_keep isl_space *isl_morph_peek_dom_space(
185 __isl_keep isl_morph *morph)
186 {
187 if (!morph)
188 return NULL;
189
190 return isl_basic_set_peek_space(morph->dom);
191 }
192
193 /* Return a copy of the domain space of "morph".
194 */
isl_morph_get_dom_space(__isl_keep isl_morph * morph)195 __isl_give isl_space *isl_morph_get_dom_space(__isl_keep isl_morph *morph)
196 {
197 return isl_space_copy(isl_morph_peek_dom_space(morph));
198 }
199
200 /* Check that the match against "space" with result "match" was successful.
201 */
check_space_match(__isl_keep isl_space * space,isl_bool match)202 static isl_stat check_space_match(__isl_keep isl_space *space, isl_bool match)
203 {
204 if (match < 0)
205 return isl_stat_error;
206 if (!match)
207 isl_die(isl_space_get_ctx(space), isl_error_invalid,
208 "spaces don't match", return isl_stat_error);
209
210 return isl_stat_ok;
211 }
212
213 /* Check that "morph" can be applied to the "space".
214 */
isl_morph_check_applies(__isl_keep isl_morph * morph,__isl_keep isl_space * space)215 isl_stat isl_morph_check_applies(__isl_keep isl_morph *morph,
216 __isl_keep isl_space *space)
217 {
218 isl_space *dom_space;
219 isl_bool applies;
220
221 dom_space = isl_morph_peek_dom_space(morph);
222 applies = isl_space_is_equal(dom_space, space);
223 return check_space_match(space, applies);
224 }
225
isl_morph_get_ran_space(__isl_keep isl_morph * morph)226 __isl_give isl_space *isl_morph_get_ran_space(__isl_keep isl_morph *morph)
227 {
228 if (!morph)
229 return NULL;
230
231 return isl_space_copy(morph->ran->dim);
232 }
233
isl_morph_dom_dim(__isl_keep isl_morph * morph,enum isl_dim_type type)234 isl_size isl_morph_dom_dim(__isl_keep isl_morph *morph, enum isl_dim_type type)
235 {
236 if (!morph)
237 return isl_size_error;
238
239 return isl_basic_set_dim(morph->dom, type);
240 }
241
isl_morph_ran_dim(__isl_keep isl_morph * morph,enum isl_dim_type type)242 isl_size isl_morph_ran_dim(__isl_keep isl_morph *morph, enum isl_dim_type type)
243 {
244 if (!morph)
245 return isl_size_error;
246
247 return isl_basic_set_dim(morph->ran, type);
248 }
249
isl_morph_remove_dom_dims(__isl_take isl_morph * morph,enum isl_dim_type type,unsigned first,unsigned n)250 __isl_give isl_morph *isl_morph_remove_dom_dims(__isl_take isl_morph *morph,
251 enum isl_dim_type type, unsigned first, unsigned n)
252 {
253 isl_size dom_offset;
254
255 if (n == 0)
256 return morph;
257
258 morph = isl_morph_cow(morph);
259 if (!morph)
260 return NULL;
261
262 dom_offset = isl_space_offset(morph->dom->dim, type);
263 if (dom_offset < 0)
264 return isl_morph_free(morph);
265
266 morph->dom = isl_basic_set_remove_dims(morph->dom, type, first, n);
267
268 morph->map = isl_mat_drop_cols(morph->map, 1 + dom_offset + first, n);
269
270 morph->inv = isl_mat_drop_rows(morph->inv, 1 + dom_offset + first, n);
271
272 if (morph->dom && morph->ran && morph->map && morph->inv)
273 return morph;
274
275 isl_morph_free(morph);
276 return NULL;
277 }
278
isl_morph_remove_ran_dims(__isl_take isl_morph * morph,enum isl_dim_type type,unsigned first,unsigned n)279 __isl_give isl_morph *isl_morph_remove_ran_dims(__isl_take isl_morph *morph,
280 enum isl_dim_type type, unsigned first, unsigned n)
281 {
282 isl_size ran_offset;
283
284 if (n == 0)
285 return morph;
286
287 morph = isl_morph_cow(morph);
288 if (!morph)
289 return NULL;
290
291 ran_offset = isl_space_offset(morph->ran->dim, type);
292 if (ran_offset < 0)
293 return isl_morph_free(morph);
294
295 morph->ran = isl_basic_set_remove_dims(morph->ran, type, first, n);
296
297 morph->map = isl_mat_drop_rows(morph->map, 1 + ran_offset + first, n);
298
299 morph->inv = isl_mat_drop_cols(morph->inv, 1 + ran_offset + first, n);
300
301 if (morph->dom && morph->ran && morph->map && morph->inv)
302 return morph;
303
304 isl_morph_free(morph);
305 return NULL;
306 }
307
308 /* Project domain of morph onto its parameter domain.
309 */
isl_morph_dom_params(__isl_take isl_morph * morph)310 __isl_give isl_morph *isl_morph_dom_params(__isl_take isl_morph *morph)
311 {
312 isl_size n;
313
314 morph = isl_morph_cow(morph);
315 if (!morph)
316 return NULL;
317 n = isl_basic_set_dim(morph->dom, isl_dim_set);
318 if (n < 0)
319 return isl_morph_free(morph);
320 morph = isl_morph_remove_dom_dims(morph, isl_dim_set, 0, n);
321 if (!morph)
322 return NULL;
323 morph->dom = isl_basic_set_params(morph->dom);
324 if (morph->dom)
325 return morph;
326
327 isl_morph_free(morph);
328 return NULL;
329 }
330
331 /* Project range of morph onto its parameter domain.
332 */
isl_morph_ran_params(__isl_take isl_morph * morph)333 __isl_give isl_morph *isl_morph_ran_params(__isl_take isl_morph *morph)
334 {
335 isl_size n;
336
337 morph = isl_morph_cow(morph);
338 if (!morph)
339 return NULL;
340 n = isl_basic_set_dim(morph->ran, isl_dim_set);
341 if (n < 0)
342 return isl_morph_free(morph);
343 morph = isl_morph_remove_ran_dims(morph, isl_dim_set, 0, n);
344 if (!morph)
345 return NULL;
346 morph->ran = isl_basic_set_params(morph->ran);
347 if (morph->ran)
348 return morph;
349
350 isl_morph_free(morph);
351 return NULL;
352 }
353
354 /* Replace the identifier of the tuple of the range of the morph by "id".
355 */
isl_morph_set_ran_tuple_id(__isl_take isl_morph * morph,__isl_keep isl_id * id)356 static __isl_give isl_morph *isl_morph_set_ran_tuple_id(
357 __isl_take isl_morph *morph, __isl_keep isl_id *id)
358 {
359 morph = isl_morph_cow(morph);
360 if (!morph)
361 return NULL;
362 morph->ran = isl_basic_set_set_tuple_id(morph->ran, isl_id_copy(id));
363 if (!morph->ran)
364 return isl_morph_free(morph);
365 return morph;
366 }
367
isl_morph_print_internal(__isl_take isl_morph * morph,FILE * out)368 void isl_morph_print_internal(__isl_take isl_morph *morph, FILE *out)
369 {
370 if (!morph)
371 return;
372
373 isl_basic_set_dump(morph->dom);
374 isl_basic_set_dump(morph->ran);
375 isl_mat_print_internal(morph->map, out, 4);
376 isl_mat_print_internal(morph->inv, out, 4);
377 }
378
isl_morph_dump(__isl_take isl_morph * morph)379 void isl_morph_dump(__isl_take isl_morph *morph)
380 {
381 isl_morph_print_internal(morph, stderr);
382 }
383
isl_morph_identity(__isl_keep isl_basic_set * bset)384 __isl_give isl_morph *isl_morph_identity(__isl_keep isl_basic_set *bset)
385 {
386 isl_mat *id;
387 isl_basic_set *universe;
388 isl_size total;
389
390 total = isl_basic_set_dim(bset, isl_dim_all);
391 if (total < 0)
392 return NULL;
393
394 id = isl_mat_identity(bset->ctx, 1 + total);
395 universe = isl_basic_set_universe(isl_space_copy(bset->dim));
396
397 return isl_morph_alloc(universe, isl_basic_set_copy(universe),
398 id, isl_mat_copy(id));
399 }
400
401 /* Create a(n identity) morphism between empty sets of the same dimension
402 * a "bset".
403 */
isl_morph_empty(__isl_keep isl_basic_set * bset)404 __isl_give isl_morph *isl_morph_empty(__isl_keep isl_basic_set *bset)
405 {
406 isl_mat *id;
407 isl_basic_set *empty;
408 isl_size total;
409
410 total = isl_basic_set_dim(bset, isl_dim_all);
411 if (total < 0)
412 return NULL;
413
414 id = isl_mat_identity(bset->ctx, 1 + total);
415 empty = isl_basic_set_empty(isl_space_copy(bset->dim));
416
417 return isl_morph_alloc(empty, isl_basic_set_copy(empty),
418 id, isl_mat_copy(id));
419 }
420
421 /* Construct a basic set described by the "n" equalities of "bset" starting
422 * at "first".
423 */
copy_equalities(__isl_keep isl_basic_set * bset,unsigned first,unsigned n)424 static __isl_give isl_basic_set *copy_equalities(__isl_keep isl_basic_set *bset,
425 unsigned first, unsigned n)
426 {
427 int i, k;
428 isl_basic_set *eq;
429 isl_size total;
430
431 total = isl_basic_set_dim(bset, isl_dim_all);
432 if (total < 0 || isl_basic_set_check_no_locals(bset) < 0)
433 return NULL;
434
435 eq = isl_basic_set_alloc_space(isl_basic_set_get_space(bset), 0, n, 0);
436 if (!eq)
437 return NULL;
438 for (i = 0; i < n; ++i) {
439 k = isl_basic_set_alloc_equality(eq);
440 if (k < 0)
441 goto error;
442 isl_seq_cpy(eq->eq[k], bset->eq[first + i], 1 + total);
443 }
444
445 return eq;
446 error:
447 isl_basic_set_free(eq);
448 return NULL;
449 }
450
451 /* Given a basic set, exploit the equalities in the basic set to construct
452 * a morphism that maps the basic set to a lower-dimensional space.
453 * Specifically, the morphism reduces the number of dimensions of type "type".
454 *
455 * We first select the equalities of interest, that is those that involve
456 * variables of type "type" and no later variables.
457 * Denote those equalities as
458 *
459 * -C(p) + M x = 0
460 *
461 * where C(p) depends on the parameters if type == isl_dim_set and
462 * is a constant if type == isl_dim_param.
463 *
464 * Use isl_mat_final_variable_compression to construct a compression
465 *
466 * x = T x'
467 *
468 * x' = Q x
469 *
470 * If T is a zero-column matrix, then the set of equality constraints
471 * do not admit a solution. In this case, an empty morphism is returned.
472 *
473 * Both matrices are extended to map the full original space to the full
474 * compressed space.
475 */
isl_basic_set_variable_compression(__isl_keep isl_basic_set * bset,enum isl_dim_type type)476 __isl_give isl_morph *isl_basic_set_variable_compression(
477 __isl_keep isl_basic_set *bset, enum isl_dim_type type)
478 {
479 unsigned otype;
480 isl_size ntype;
481 unsigned orest;
482 unsigned nrest;
483 isl_size total;
484 int f_eq, n_eq;
485 isl_space *space;
486 isl_mat *E, *Q, *C;
487 isl_basic_set *dom, *ran;
488
489 if (!bset)
490 return NULL;
491
492 if (isl_basic_set_plain_is_empty(bset))
493 return isl_morph_empty(bset);
494
495 if (isl_basic_set_check_no_locals(bset) < 0)
496 return NULL;
497
498 ntype = isl_basic_set_dim(bset, type);
499 total = isl_basic_set_dim(bset, isl_dim_all);
500 if (ntype < 0 || total < 0)
501 return NULL;
502 otype = isl_basic_set_offset(bset, type);
503 orest = otype + ntype;
504 nrest = total - (orest - 1);
505
506 for (f_eq = 0; f_eq < bset->n_eq; ++f_eq)
507 if (isl_seq_first_non_zero(bset->eq[f_eq] + orest, nrest) == -1)
508 break;
509 for (n_eq = 0; f_eq + n_eq < bset->n_eq; ++n_eq)
510 if (isl_seq_first_non_zero(bset->eq[f_eq + n_eq] + otype, ntype) == -1)
511 break;
512 if (n_eq == 0)
513 return isl_morph_identity(bset);
514
515 E = isl_mat_sub_alloc6(bset->ctx, bset->eq, f_eq, n_eq, 0, orest);
516 C = isl_mat_final_variable_compression(E, otype - 1, &Q);
517 if (!Q)
518 C = isl_mat_free(C);
519 if (C && C->n_col == 0) {
520 isl_mat_free(C);
521 isl_mat_free(Q);
522 return isl_morph_empty(bset);
523 }
524
525 Q = isl_mat_diagonal(Q, isl_mat_identity(bset->ctx, nrest));
526 C = isl_mat_diagonal(C, isl_mat_identity(bset->ctx, nrest));
527
528 space = isl_space_copy(bset->dim);
529 space = isl_space_drop_dims(space, type, 0, ntype);
530 space = isl_space_add_dims(space, type, ntype - n_eq);
531 ran = isl_basic_set_universe(space);
532 dom = copy_equalities(bset, f_eq, n_eq);
533
534 return isl_morph_alloc(dom, ran, Q, C);
535 }
536
537 /* Given a basic set, exploit the equalities in the basic set to construct
538 * a morphism that maps the basic set to a lower-dimensional space
539 * with identifier "id".
540 * Specifically, the morphism reduces the number of set dimensions.
541 */
isl_basic_set_variable_compression_with_id(__isl_keep isl_basic_set * bset,__isl_keep isl_id * id)542 __isl_give isl_morph *isl_basic_set_variable_compression_with_id(
543 __isl_keep isl_basic_set *bset, __isl_keep isl_id *id)
544 {
545 isl_morph *morph;
546
547 morph = isl_basic_set_variable_compression(bset, isl_dim_set);
548 morph = isl_morph_set_ran_tuple_id(morph, id);
549 return morph;
550 }
551
552 /* Construct a parameter compression for "bset".
553 * We basically just call isl_mat_parameter_compression with the right input
554 * and then extend the resulting matrix to include the variables.
555 *
556 * The implementation assumes that "bset" does not have any equalities
557 * that only involve the parameters and that isl_basic_set_gauss has
558 * been applied to "bset".
559 *
560 * Let the equalities be given as
561 *
562 * B(p) + A x = 0.
563 *
564 * We use isl_mat_parameter_compression_ext to compute the compression
565 *
566 * p = T p'.
567 */
isl_basic_set_parameter_compression(__isl_keep isl_basic_set * bset)568 __isl_give isl_morph *isl_basic_set_parameter_compression(
569 __isl_keep isl_basic_set *bset)
570 {
571 isl_size nparam;
572 isl_size nvar;
573 isl_size n_div;
574 int n_eq;
575 isl_mat *H, *B;
576 isl_mat *map, *inv;
577 isl_basic_set *dom, *ran;
578
579 if (!bset)
580 return NULL;
581
582 if (isl_basic_set_plain_is_empty(bset))
583 return isl_morph_empty(bset);
584 if (bset->n_eq == 0)
585 return isl_morph_identity(bset);
586
587 n_eq = bset->n_eq;
588 nparam = isl_basic_set_dim(bset, isl_dim_param);
589 nvar = isl_basic_set_dim(bset, isl_dim_set);
590 n_div = isl_basic_set_dim(bset, isl_dim_div);
591 if (nparam < 0 || nvar < 0 || n_div < 0)
592 return NULL;
593
594 if (isl_seq_first_non_zero(bset->eq[bset->n_eq - 1] + 1 + nparam,
595 nvar + n_div) == -1)
596 isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
597 "input not allowed to have parameter equalities",
598 return NULL);
599 if (n_eq > nvar + n_div)
600 isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
601 "input not gaussed", return NULL);
602
603 B = isl_mat_sub_alloc6(bset->ctx, bset->eq, 0, n_eq, 0, 1 + nparam);
604 H = isl_mat_sub_alloc6(bset->ctx, bset->eq,
605 0, n_eq, 1 + nparam, nvar + n_div);
606 inv = isl_mat_parameter_compression_ext(B, H);
607 inv = isl_mat_diagonal(inv, isl_mat_identity(bset->ctx, nvar));
608 map = isl_mat_right_inverse(isl_mat_copy(inv));
609
610 dom = isl_basic_set_universe(isl_space_copy(bset->dim));
611 ran = isl_basic_set_universe(isl_space_copy(bset->dim));
612
613 return isl_morph_alloc(dom, ran, map, inv);
614 }
615
616 /* Construct an isl_multi_aff that corresponds
617 * to the affine transformation matrix "mat" and
618 * that lives in an anonymous space.
619 */
isl_multi_aff_from_aff_mat_anonymous(__isl_take isl_mat * mat)620 static __isl_give isl_multi_aff *isl_multi_aff_from_aff_mat_anonymous(
621 __isl_take isl_mat *mat)
622 {
623 isl_size n_row, n_col;
624 isl_ctx *ctx;
625 isl_space *space;
626
627 ctx = isl_mat_get_ctx(mat);
628 n_row = isl_mat_rows(mat);
629 n_col = isl_mat_cols(mat);
630 if (n_row < 0 || n_col < 0)
631 space = NULL;
632 else
633 space = isl_space_alloc(ctx, 0, n_col - 1, n_row - 1);
634
635 return isl_multi_aff_from_aff_mat(space, mat);
636 }
637
638 /* Apply the morphism to the basic set.
639 * In particular, compute the preimage of "bset" under the inverse mapping
640 * in morph and intersect with the range of the morphism.
641 * Note that the mapping in morph applies to both parameters and set dimensions,
642 * so the parameters need to be treated as set dimensions during the call
643 * to isl_basic_set_preimage_multi_aff.
644 */
isl_morph_basic_set(__isl_take isl_morph * morph,__isl_take isl_basic_set * bset)645 __isl_give isl_basic_set *isl_morph_basic_set(__isl_take isl_morph *morph,
646 __isl_take isl_basic_set *bset)
647 {
648 isl_size n_param;
649 isl_space *space;
650 isl_multi_aff *ma;
651
652 if (!morph || isl_basic_set_check_equal_space(bset, morph->dom) < 0)
653 goto error;
654 n_param = isl_basic_set_dim(morph->dom, isl_dim_param);
655 if (n_param < 0)
656 goto error;
657
658 ma = isl_multi_aff_from_aff_mat_anonymous(isl_mat_copy(morph->inv));
659
660 bset = isl_basic_set_move_dims(bset, isl_dim_set, 0,
661 isl_dim_param, 0, n_param);
662 bset = isl_basic_set_preimage_multi_aff(bset, ma);
663 space = isl_basic_set_get_space(morph->ran);
664 bset = isl_basic_set_reset_space(bset, space);
665 bset = isl_basic_set_intersect(bset, isl_basic_set_copy(morph->ran));
666
667 isl_morph_free(morph);
668 return bset;
669 error:
670 isl_morph_free(morph);
671 isl_basic_set_free(bset);
672 return NULL;
673 }
674
675 /* Apply the morphism to the set.
676 * In particular, compute the preimage of "set" under the inverse mapping
677 * in morph and intersect with the range of the morphism.
678 * Note that the mapping in morph applies to both parameters and set dimensions,
679 * so the parameters need to be treated as set dimensions during the call
680 * to isl_set_preimage_multi_aff.
681 */
isl_morph_set(__isl_take isl_morph * morph,__isl_take isl_set * set)682 __isl_give isl_set *isl_morph_set(__isl_take isl_morph *morph,
683 __isl_take isl_set *set)
684 {
685 isl_size n_param;
686 isl_space *space;
687 isl_multi_aff *ma;
688 isl_basic_set *ran;
689
690 if (!morph || isl_set_basic_set_check_equal_space(set, morph->dom) < 0)
691 goto error;
692 n_param = isl_basic_set_dim(morph->dom, isl_dim_param);
693 if (n_param < 0)
694 goto error;
695
696 ma = isl_multi_aff_from_aff_mat_anonymous(isl_mat_copy(morph->inv));
697
698 set = isl_set_move_dims(set, isl_dim_set, 0, isl_dim_param, 0, n_param);
699 set = isl_set_preimage_multi_aff(set, ma);
700 space = isl_basic_set_get_space(morph->ran);
701 set = isl_set_reset_space(set, space);
702 ran = isl_basic_set_copy(morph->ran);
703 set = isl_set_intersect(set, isl_set_from_basic_set(ran));
704
705 isl_morph_free(morph);
706 return set;
707 error:
708 isl_set_free(set);
709 isl_morph_free(morph);
710 return NULL;
711 }
712
713 /* Construct a morphism that first does morph2 and then morph1.
714 */
isl_morph_compose(__isl_take isl_morph * morph1,__isl_take isl_morph * morph2)715 __isl_give isl_morph *isl_morph_compose(__isl_take isl_morph *morph1,
716 __isl_take isl_morph *morph2)
717 {
718 isl_mat *map, *inv;
719 isl_basic_set *dom, *ran;
720
721 if (!morph1 || !morph2)
722 goto error;
723
724 map = isl_mat_product(isl_mat_copy(morph1->map), isl_mat_copy(morph2->map));
725 inv = isl_mat_product(isl_mat_copy(morph2->inv), isl_mat_copy(morph1->inv));
726 dom = isl_morph_basic_set(isl_morph_inverse(isl_morph_copy(morph2)),
727 isl_basic_set_copy(morph1->dom));
728 dom = isl_basic_set_intersect(dom, isl_basic_set_copy(morph2->dom));
729 ran = isl_morph_basic_set(isl_morph_copy(morph1),
730 isl_basic_set_copy(morph2->ran));
731 ran = isl_basic_set_intersect(ran, isl_basic_set_copy(morph1->ran));
732
733 isl_morph_free(morph1);
734 isl_morph_free(morph2);
735
736 return isl_morph_alloc(dom, ran, map, inv);
737 error:
738 isl_morph_free(morph1);
739 isl_morph_free(morph2);
740 return NULL;
741 }
742
isl_morph_inverse(__isl_take isl_morph * morph)743 __isl_give isl_morph *isl_morph_inverse(__isl_take isl_morph *morph)
744 {
745 isl_basic_set *bset;
746 isl_mat *mat;
747
748 morph = isl_morph_cow(morph);
749 if (!morph)
750 return NULL;
751
752 bset = morph->dom;
753 morph->dom = morph->ran;
754 morph->ran = bset;
755
756 mat = morph->map;
757 morph->map = morph->inv;
758 morph->inv = mat;
759
760 return morph;
761 }
762
763 /* We detect all the equalities first to avoid implicit equalities
764 * being discovered during the computations. In particular,
765 * the compression on the variables could expose additional stride
766 * constraints on the parameters. This would result in existentially
767 * quantified variables after applying the resulting morph, which
768 * in turn could break invariants of the calling functions.
769 */
isl_basic_set_full_compression(__isl_keep isl_basic_set * bset)770 __isl_give isl_morph *isl_basic_set_full_compression(
771 __isl_keep isl_basic_set *bset)
772 {
773 isl_morph *morph, *morph2;
774
775 bset = isl_basic_set_copy(bset);
776 bset = isl_basic_set_detect_equalities(bset);
777
778 morph = isl_basic_set_variable_compression(bset, isl_dim_param);
779 bset = isl_morph_basic_set(isl_morph_copy(morph), bset);
780
781 morph2 = isl_basic_set_parameter_compression(bset);
782 bset = isl_morph_basic_set(isl_morph_copy(morph2), bset);
783
784 morph = isl_morph_compose(morph2, morph);
785
786 morph2 = isl_basic_set_variable_compression(bset, isl_dim_set);
787 isl_basic_set_free(bset);
788
789 morph = isl_morph_compose(morph2, morph);
790
791 return morph;
792 }
793
isl_morph_vec(__isl_take isl_morph * morph,__isl_take isl_vec * vec)794 __isl_give isl_vec *isl_morph_vec(__isl_take isl_morph *morph,
795 __isl_take isl_vec *vec)
796 {
797 if (!morph)
798 goto error;
799
800 vec = isl_mat_vec_product(isl_mat_copy(morph->map), vec);
801
802 isl_morph_free(morph);
803 return vec;
804 error:
805 isl_morph_free(morph);
806 isl_vec_free(vec);
807 return NULL;
808 }
809