isl_tab_cone_is_bounded: start over after computing sign_of_max
[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_cow(constraint->bmap);
217         constraint->bmap = isl_basic_map_extend_dim(constraint->bmap,
218                                 isl_dim_copy(constraint->bmap->dim), 1, 0, 0);
219         if (!constraint->bmap)
220                 goto error;
221         constraint->line = &constraint->bmap->eq[0];
222         *pos = isl_basic_map_alloc_div(constraint->bmap);
223         if (*pos < 0)
224                 goto error;
225         isl_seq_cpy(constraint->bmap->div[*pos], div->line[0],
226                         1 + 1 + isl_basic_map_total_dim(constraint->bmap));
227         isl_div_free(div);
228         return constraint;
229 error:
230         isl_constraint_free(constraint);
231         isl_div_free(div);
232         return NULL;
233 }
234
235 int isl_constraint_dim(struct isl_constraint *constraint,
236         enum isl_dim_type type)
237 {
238         if (!constraint)
239                 return -1;
240         return n(constraint, type);
241 }
242
243 void isl_constraint_get_constant(struct isl_constraint *constraint, isl_int *v)
244 {
245         if (!constraint)
246                 return;
247         isl_int_set(*v, constraint->line[0][0]);
248 }
249
250 void isl_constraint_get_coefficient(struct isl_constraint *constraint,
251         enum isl_dim_type type, int pos, isl_int *v)
252 {
253         if (!constraint)
254                 return;
255
256         isl_assert(constraint->ctx, pos < n(constraint, type), return);
257         isl_int_set(*v, constraint->line[0][offset(constraint, type) + pos]);
258 }
259
260 struct isl_div *isl_constraint_div(struct isl_constraint *constraint, int pos)
261 {
262         if (!constraint)
263                 return NULL;
264
265         isl_assert(constraint->ctx, pos < n(constraint, isl_dim_div),
266                         return NULL);
267         return isl_basic_map_div(isl_basic_map_copy(constraint->bmap), pos);
268 }
269
270 void isl_constraint_set_constant(struct isl_constraint *constraint, isl_int v)
271 {
272         if (!constraint)
273                 return;
274         isl_int_set(constraint->line[0][0], v);
275 }
276
277 void isl_constraint_set_coefficient(struct isl_constraint *constraint,
278         enum isl_dim_type type, int pos, isl_int v)
279 {
280         if (!constraint)
281                 return;
282
283         isl_assert(constraint->ctx, pos < n(constraint, type), return);
284         isl_int_set(constraint->line[0][offset(constraint, type) + pos], v);
285 }
286
287 void isl_constraint_clear(struct isl_constraint *constraint)
288 {
289         struct isl_basic_set *bset;
290         unsigned total;
291
292         if (!constraint)
293                 return;
294         total = isl_basic_map_total_dim(constraint->bmap);
295         isl_seq_clr(constraint->line[0], 1 + total);
296 }
297
298 struct isl_constraint *isl_constraint_negate(struct isl_constraint *constraint)
299 {
300         unsigned total;
301
302         if (!constraint)
303                 return NULL;
304
305         isl_assert(constraint->ctx, !isl_constraint_is_equality(constraint),
306                         goto error);
307         isl_assert(constraint->ctx, constraint->bmap->ref == 1, goto error);
308         total = isl_basic_map_total_dim(constraint->bmap);
309         isl_seq_neg(constraint->line[0], constraint->line[0], 1 + total);
310         isl_int_sub_ui(constraint->line[0][0], constraint->line[0][0], 1);
311         ISL_F_CLR(constraint->bmap, ISL_BASIC_MAP_NORMALIZED);
312         return constraint;
313 error:
314         isl_constraint_free(constraint);
315         return NULL;
316 }
317
318 int isl_constraint_is_equality(struct isl_constraint *constraint)
319 {
320         if (!constraint)
321                 return -1;
322         return constraint->line >= constraint->bmap->eq;
323 }
324
325
326 struct isl_basic_set *isl_basic_set_from_constraint(
327         struct isl_constraint *constraint)
328 {
329         int k;
330         struct isl_basic_set *constraint_bset, *bset;
331         isl_int *c;
332         unsigned dim;
333         unsigned nparam;
334         unsigned total;
335
336         if (!constraint)
337                 return NULL;
338
339         isl_assert(constraint->ctx,n(constraint, isl_dim_in) == 0, goto error);
340
341         constraint_bset = (struct isl_basic_set *)constraint->bmap;
342         bset = isl_basic_set_universe_like(constraint_bset);
343         bset = isl_basic_set_align_divs(bset, constraint_bset);
344         nparam = isl_basic_set_n_param(bset);
345         dim = isl_basic_set_n_dim(bset);
346         bset = isl_basic_set_cow(bset);
347         bset = isl_basic_set_extend(bset, nparam, dim, 0, 1, 1);
348         if (isl_constraint_is_equality(constraint)) {
349                 k = isl_basic_set_alloc_equality(bset);
350                 if (k < 0)
351                         goto error;
352                 c = bset->eq[k];
353         }
354         else {
355                 k = isl_basic_set_alloc_inequality(bset);
356                 if (k < 0)
357                         goto error;
358                 c = bset->ineq[k];
359         }
360         total = isl_basic_set_total_dim(bset);
361         isl_seq_cpy(c, constraint->line[0], 1 + total);
362         isl_constraint_free(constraint);
363         return bset;
364 error:
365         isl_constraint_free(constraint);
366         isl_basic_set_free(bset);
367         return NULL;
368 }
369
370 int isl_basic_set_has_defining_equality(
371         struct isl_basic_set *bset, enum isl_dim_type type, int pos,
372         struct isl_constraint **c)
373 {
374         int i;
375         unsigned offset;
376         unsigned total;
377
378         if (!bset)
379                 return -1;
380         offset = basic_set_offset(bset, type);
381         total = isl_basic_set_total_dim(bset);
382         isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
383         for (i = 0; i < bset->n_eq; ++i)
384                 if (!isl_int_is_zero(bset->eq[i][offset + pos]) &&
385                     isl_seq_first_non_zero(bset->eq[i]+offset+pos+1,
386                                            1+total-offset-pos-1) == -1) {
387                         *c= isl_basic_set_constraint(isl_basic_set_copy(bset),
388                                                                 &bset->eq[i]);
389                         return 1;
390                 }
391         return 0;
392 }
393
394 int isl_basic_set_has_defining_inequalities(
395         struct isl_basic_set *bset, enum isl_dim_type type, int pos,
396         struct isl_constraint **lower,
397         struct isl_constraint **upper)
398 {
399         int i, j;
400         unsigned offset;
401         unsigned total;
402         isl_int m;
403         isl_int **lower_line, **upper_line;
404
405         if (!bset)
406                 return -1;
407         offset = basic_set_offset(bset, type);
408         total = isl_basic_set_total_dim(bset);
409         isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
410         isl_int_init(m);
411         for (i = 0; i < bset->n_ineq; ++i) {
412                 if (isl_int_is_zero(bset->ineq[i][offset + pos]))
413                         continue;
414                 if (isl_int_is_one(bset->ineq[i][offset + pos]))
415                         continue;
416                 if (isl_int_is_negone(bset->ineq[i][offset + pos]))
417                         continue;
418                 if (isl_seq_first_non_zero(bset->ineq[i]+offset+pos+1,
419                                                 1+total-offset-pos-1) != -1)
420                         continue;
421                 for (j = i + 1; j < bset->n_ineq; ++j) {
422                         if (!isl_seq_is_neg(bset->ineq[i]+1, bset->ineq[j]+1,
423                                             total))
424                                 continue;
425                         isl_int_add(m, bset->ineq[i][0], bset->ineq[j][0]);
426                         if (isl_int_abs_ge(m, bset->ineq[i][offset+pos]))
427                                 continue;
428
429                         if (isl_int_is_pos(bset->ineq[i][offset+pos])) {
430                                 lower_line = &bset->ineq[i];
431                                 upper_line = &bset->ineq[j];
432                         } else {
433                                 lower_line = &bset->ineq[j];
434                                 upper_line = &bset->ineq[i];
435                         }
436                         *lower = isl_basic_set_constraint(
437                                         isl_basic_set_copy(bset), lower_line);
438                         *upper = isl_basic_set_constraint(
439                                         isl_basic_set_copy(bset), upper_line);
440                         isl_int_clear(m);
441                         return 1;
442                 }
443         }
444         *lower = NULL;
445         *upper = NULL;
446         isl_int_clear(m);
447         return 0;
448 }