isl_basic_map: put inequalities before equalities
[platform/upstream/isl.git] / isl_constraint.c
1 #include <isl_constraint.h>
2 #include "isl_map_private.h"
3
4 static unsigned n(struct isl_constraint *c, enum isl_dim_type type)
5 {
6         return isl_basic_map_dim(c->bmap, type);
7 }
8
9 static unsigned offset(struct isl_constraint *c, enum isl_dim_type type)
10 {
11         struct isl_dim *dim = c->bmap->dim;
12         switch (type) {
13         case isl_dim_param:     return 1;
14         case isl_dim_in:        return 1 + dim->nparam;
15         case isl_dim_out:       return 1 + dim->nparam + dim->n_in;
16         case isl_dim_div:       return 1 + dim->nparam + dim->n_in + dim->n_out;
17         }
18 }
19
20 static unsigned basic_set_offset(struct isl_basic_set *bset,
21                                                         enum isl_dim_type type)
22 {
23         struct isl_dim *dim = bset->dim;
24         switch (type) {
25         case isl_dim_param:     return 1;
26         case isl_dim_in:        return 1 + dim->nparam;
27         case isl_dim_out:       return 1 + dim->nparam + dim->n_in;
28         case isl_dim_div:       return 1 + dim->nparam + dim->n_in + dim->n_out;
29         }
30 }
31
32 struct isl_constraint *isl_basic_map_constraint(struct isl_basic_map *bmap,
33         isl_int **line)
34 {
35         struct isl_constraint *constraint;
36
37         if (!bmap || !line)
38                 goto error;
39         
40         constraint = isl_alloc_type(bmap->ctx, struct isl_constraint);
41         if (!constraint)
42                 goto error;
43
44         constraint->ctx = bmap->ctx;
45         isl_ctx_ref(constraint->ctx);
46         constraint->ref = 1;
47         constraint->bmap = bmap;
48         constraint->line = line;
49
50         return constraint;
51 error:
52         isl_basic_map_free(bmap);
53         return NULL;
54 }
55
56 struct isl_constraint *isl_basic_set_constraint(struct isl_basic_set *bset,
57         isl_int **line)
58 {
59         return isl_basic_map_constraint((struct isl_basic_map *)bset, line);
60 }
61
62 struct isl_constraint *isl_equality_alloc(struct isl_dim *dim)
63 {
64         struct isl_basic_map *bmap;
65
66         if (!dim)
67                 return NULL;
68
69         bmap = isl_basic_map_alloc_dim(dim, 0, 1, 0);
70         if (!bmap)
71                 return NULL;
72
73         isl_basic_map_alloc_equality(bmap);
74         isl_seq_clr(bmap->eq[0], 1 + isl_basic_map_total_dim(bmap));
75         return isl_basic_map_constraint(bmap, &bmap->eq[0]);
76 }
77
78 struct isl_constraint *isl_inequality_alloc(struct isl_dim *dim)
79 {
80         struct isl_basic_map *bmap;
81
82         if (!dim)
83                 return NULL;
84
85         bmap = isl_basic_map_alloc_dim(dim, 0, 0, 1);
86         if (!bmap)
87                 return NULL;
88
89         isl_basic_map_alloc_inequality(bmap);
90         isl_seq_clr(bmap->ineq[0], 1 + isl_basic_map_total_dim(bmap));
91         return isl_basic_map_constraint(bmap, &bmap->ineq[0]);
92 }
93
94 struct isl_constraint *isl_constraint_dup(struct isl_constraint *c)
95 {
96         if (!c)
97                 return NULL;
98
99         return isl_basic_map_constraint(isl_basic_map_copy(c->bmap), c->line);
100 }
101
102 struct isl_constraint *isl_constraint_cow(struct isl_constraint *c)
103 {
104         if (!c)
105                 return NULL;
106
107         if (c->ref == 1)
108                 return c;
109         c->ref--;
110         return isl_constraint_dup(c);
111 }
112
113 struct isl_constraint *isl_constraint_copy(struct isl_constraint *constraint)
114 {
115         if (!constraint)
116                 return NULL;
117
118         constraint->ref++;
119         return constraint;
120 }
121
122 struct isl_constraint *isl_constraint_free(struct isl_constraint *c)
123 {
124         if (!c)
125                 return;
126
127         if (--c->ref > 0)
128                 return;
129
130         isl_basic_map_free(c->bmap);
131         isl_ctx_deref(c->ctx);
132         free(c);
133 }
134
135 struct isl_constraint *isl_basic_set_first_constraint(
136         struct isl_basic_set *bset)
137 {
138         struct isl_constraint *c;
139
140         if (!bset)
141                 return NULL;
142
143         if (bset->n_eq > 0)
144                 return isl_basic_set_constraint(bset, &bset->eq[0]);
145
146         if (bset->n_ineq > 0)
147                 return isl_basic_set_constraint(bset, &bset->ineq[0]);
148
149         isl_basic_set_free(bset);
150         return NULL;
151 }
152
153 struct isl_constraint *isl_constraint_next(struct isl_constraint *c)
154 {
155         c = isl_constraint_cow(c);
156         if (c->line >= c->bmap->eq) {
157                 c->line++;
158                 if (c->line < c->bmap->eq + c->bmap->n_eq)
159                         return c;
160                 c->line = c->bmap->ineq;
161         } else
162                 c->line++;
163         if (c->line < c->bmap->ineq + c->bmap->n_ineq)
164                 return c;
165         isl_constraint_free(c);
166         return NULL;
167 }
168
169 int isl_constraint_is_equal(struct isl_constraint *constraint1,
170         struct isl_constraint *constraint2)
171 {
172         if (!constraint1 || !constraint2)
173                 return 0;
174         return constraint1->bmap == constraint2->bmap &&
175                constraint1->line == constraint2->line;
176 }
177
178 struct isl_basic_map *isl_basic_map_add_constraint(
179         struct isl_basic_map *bmap, struct isl_constraint *constraint)
180 {
181         if (!bmap || !constraint)
182                 goto error;
183
184         isl_assert(constraint->ctx,
185                 isl_dim_equal(bmap->dim, constraint->bmap->dim), goto error);
186
187         bmap = isl_basic_map_intersect(bmap,
188                                     isl_basic_map_copy(constraint->bmap));
189         isl_constraint_free(constraint);
190         return bmap;
191 error:
192         isl_basic_map_free(bmap);
193         isl_constraint_free(constraint);
194         return NULL;
195 }
196
197 struct isl_basic_set *isl_basic_set_add_constraint(
198         struct isl_basic_set *bset, struct isl_constraint *constraint)
199 {
200         return (struct isl_basic_set *)
201                 isl_basic_map_add_constraint((struct isl_basic_map *)bset,
202                                                 constraint);
203 }
204
205 struct isl_constraint *isl_constraint_add_div(struct isl_constraint *constraint,
206         struct isl_div *div, int *pos)
207 {
208         if (!constraint || !div)
209                 goto error;
210
211         isl_assert(constraint->ctx,
212             isl_dim_equal(div->bmap->dim, constraint->bmap->dim), goto error);
213         isl_assert(constraint->ctx,
214             constraint->bmap->n_eq + constraint->bmap->n_ineq == 1, goto error);
215
216         constraint->bmap = isl_basic_map_extend_dim(constraint->bmap,
217                                 isl_dim_copy(constraint->bmap->dim), 1, 0, 0);
218         if (!constraint->bmap)
219                 goto error;
220         constraint->line = &constraint->bmap->eq[0];
221         *pos = isl_basic_map_alloc_div(constraint->bmap);
222         if (*pos < 0)
223                 goto error;
224         isl_seq_cpy(constraint->bmap->div[*pos], div->line[0],
225                         1 + 1 + isl_basic_map_total_dim(constraint->bmap));
226         isl_div_free(div);
227         return constraint;
228 error:
229         isl_constraint_free(constraint);
230         isl_div_free(div);
231         return NULL;
232 }
233
234 int isl_constraint_dim(struct isl_constraint *constraint,
235         enum isl_dim_type type)
236 {
237         if (!constraint)
238                 return -1;
239         return n(constraint, type);
240 }
241
242 void isl_constraint_get_constant(struct isl_constraint *constraint, isl_int *v)
243 {
244         if (!constraint)
245                 return;
246         isl_int_set(*v, constraint->line[0][0]);
247 }
248
249 void isl_constraint_get_coefficient(struct isl_constraint *constraint,
250         enum isl_dim_type type, int pos, isl_int *v)
251 {
252         if (!constraint)
253                 return;
254
255         isl_assert(constraint->ctx, pos < n(constraint, type), return);
256         isl_int_set(*v, constraint->line[0][offset(constraint, type) + pos]);
257 }
258
259 struct isl_div *isl_constraint_div(struct isl_constraint *constraint, int pos)
260 {
261         if (!constraint)
262                 return NULL;
263
264         isl_assert(constraint->ctx, pos < n(constraint, isl_dim_div),
265                         return NULL);
266         return isl_basic_map_div(constraint->bmap, constraint->bmap->div+pos);
267 }
268
269 void isl_constraint_set_constant(struct isl_constraint *constraint, isl_int v)
270 {
271         if (!constraint)
272                 return;
273         isl_int_set(constraint->line[0][0], v);
274 }
275
276 void isl_constraint_set_coefficient(struct isl_constraint *constraint,
277         enum isl_dim_type type, int pos, isl_int v)
278 {
279         if (!constraint)
280                 return;
281
282         isl_assert(constraint->ctx, pos < n(constraint, type), return);
283         isl_int_set(constraint->line[0][offset(constraint, type) + pos], v);
284 }
285
286 void isl_constraint_clear(struct isl_constraint *constraint)
287 {
288         struct isl_basic_set *bset;
289         unsigned total;
290
291         if (!constraint)
292                 return;
293         total = isl_basic_map_total_dim(constraint->bmap);
294         isl_seq_clr(constraint->line[0], 1 + total);
295 }
296
297 struct isl_constraint *isl_constraint_negate(struct isl_constraint *constraint)
298 {
299         unsigned total;
300
301         if (!constraint)
302                 return NULL;
303
304         isl_assert(constraint->ctx, !isl_constraint_is_equality(constraint),
305                         goto error);
306         isl_assert(constraint->ctx, constraint->bmap->ref == 1, goto error);
307         total = isl_basic_map_total_dim(constraint->bmap);
308         isl_seq_neg(constraint->line[0], constraint->line[0], 1 + total);
309         isl_int_sub_ui(constraint->line[0][0], constraint->line[0][0], 1);
310         ISL_F_CLR(constraint->bmap, ISL_BASIC_MAP_NORMALIZED);
311         return constraint;
312 error:
313         isl_constraint_free(constraint);
314         return NULL;
315 }
316
317 int isl_constraint_is_equality(struct isl_constraint *constraint)
318 {
319         if (!constraint)
320                 return -1;
321         return constraint->line >= constraint->bmap->eq;
322 }
323
324
325 struct isl_basic_set *isl_basic_set_from_constraint(
326         struct isl_constraint *constraint)
327 {
328         int k;
329         struct isl_basic_set *constraint_bset, *bset;
330         isl_int *c;
331         unsigned dim;
332         unsigned nparam;
333         unsigned total;
334
335         if (!constraint)
336                 return NULL;
337
338         isl_assert(constraint->ctx,n(constraint, isl_dim_in) == 0, goto error);
339
340         constraint_bset = (struct isl_basic_set *)constraint->bmap;
341         bset = isl_basic_set_universe_like(constraint_bset);
342         bset = isl_basic_set_align_divs(bset, constraint_bset);
343         nparam = isl_basic_set_n_param(bset);
344         dim = isl_basic_set_n_dim(bset);
345         bset = isl_basic_set_extend(bset, nparam, dim, 0, 1, 1);
346         if (isl_constraint_is_equality(constraint)) {
347                 k = isl_basic_set_alloc_equality(bset);
348                 if (k < 0)
349                         goto error;
350                 c = bset->eq[k];
351         }
352         else {
353                 k = isl_basic_set_alloc_inequality(bset);
354                 if (k < 0)
355                         goto error;
356                 c = bset->ineq[k];
357         }
358         total = isl_basic_set_total_dim(bset);
359         isl_seq_cpy(c, constraint->line[0], 1 + total);
360         isl_constraint_free(constraint);
361         return bset;
362 error:
363         isl_constraint_free(constraint);
364         isl_basic_set_free(bset);
365         return NULL;
366 }
367
368 int isl_basic_set_has_defining_equality(
369         struct isl_basic_set *bset, enum isl_dim_type type, int pos,
370         struct isl_constraint **c)
371 {
372         int i;
373         unsigned offset;
374         unsigned total;
375
376         if (!bset)
377                 return -1;
378         offset = basic_set_offset(bset, type);
379         total = isl_basic_set_total_dim(bset);
380         isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
381         for (i = 0; i < bset->n_eq; ++i)
382                 if (!isl_int_is_zero(bset->eq[i][offset + pos]) &&
383                     isl_seq_first_non_zero(bset->eq[i]+offset+pos+1,
384                                            1+total-offset-pos-1) == -1) {
385                         *c= isl_basic_set_constraint(isl_basic_set_copy(bset),
386                                                                 &bset->eq[i]);
387                         return 1;
388                 }
389         return 0;
390 }
391
392 int isl_basic_set_has_defining_inequalities(
393         struct isl_basic_set *bset, enum isl_dim_type type, int pos,
394         struct isl_constraint **lower,
395         struct isl_constraint **upper)
396 {
397         int i, j;
398         unsigned offset;
399         unsigned total;
400         isl_int m;
401         isl_int **lower_line, **upper_line;
402
403         if (!bset)
404                 return -1;
405         offset = basic_set_offset(bset, type);
406         total = isl_basic_set_total_dim(bset);
407         isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
408         isl_int_init(m);
409         for (i = 0; i < bset->n_ineq; ++i) {
410                 if (isl_int_is_zero(bset->ineq[i][offset + pos]))
411                         continue;
412                 if (isl_int_is_one(bset->ineq[i][offset + pos]))
413                         continue;
414                 if (isl_int_is_negone(bset->ineq[i][offset + pos]))
415                         continue;
416                 if (isl_seq_first_non_zero(bset->ineq[i]+offset+pos+1,
417                                                 1+total-offset-pos-1) != -1)
418                         continue;
419                 for (j = i + i; j < bset->n_ineq; ++j) {
420                         if (!isl_seq_is_neg(bset->ineq[i]+1, bset->ineq[j]+1,
421                                             total))
422                                 continue;
423                         isl_int_add(m, bset->ineq[i][0], bset->ineq[j][0]);
424                         if (isl_int_abs_ge(m, bset->ineq[i][offset+pos]))
425                                 continue;
426
427                         if (isl_int_is_pos(bset->ineq[i][offset+pos])) {
428                                 lower_line = &bset->ineq[i];
429                                 upper_line = &bset->ineq[j];
430                         } else {
431                                 lower_line = &bset->ineq[j];
432                                 upper_line = &bset->ineq[i];
433                         }
434                         *lower = isl_basic_set_constraint(
435                                         isl_basic_set_copy(bset), lower_line);
436                         *upper = isl_basic_set_constraint(
437                                         isl_basic_set_copy(bset), upper_line);
438                         isl_int_clear(m);
439                         return 1;
440                 }
441         }
442         *lower = NULL;
443         *upper = NULL;
444         isl_int_clear(m);
445         return 0;
446 }