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56cf8686 | 1 | /* Data references and dependences detectors. |
d1e082c2 | 2 | Copyright (C) 2003-2013 Free Software Foundation, Inc. |
0ff4040e | 3 | Contributed by Sebastian Pop <pop@cri.ensmp.fr> |
56cf8686 SP |
4 | |
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 9 | Software Foundation; either version 3, or (at your option) any later |
56cf8686 SP |
10 | version. |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
56cf8686 SP |
20 | |
21 | /* This pass walks a given loop structure searching for array | |
22 | references. The information about the array accesses is recorded | |
b8698a0f L |
23 | in DATA_REFERENCE structures. |
24 | ||
25 | The basic test for determining the dependences is: | |
26 | given two access functions chrec1 and chrec2 to a same array, and | |
27 | x and y two vectors from the iteration domain, the same element of | |
56cf8686 SP |
28 | the array is accessed twice at iterations x and y if and only if: |
29 | | chrec1 (x) == chrec2 (y). | |
b8698a0f | 30 | |
56cf8686 | 31 | The goals of this analysis are: |
b8698a0f | 32 | |
56cf8686 SP |
33 | - to determine the independence: the relation between two |
34 | independent accesses is qualified with the chrec_known (this | |
35 | information allows a loop parallelization), | |
b8698a0f | 36 | |
56cf8686 SP |
37 | - when two data references access the same data, to qualify the |
38 | dependence relation with classic dependence representations: | |
b8698a0f | 39 | |
56cf8686 SP |
40 | - distance vectors |
41 | - direction vectors | |
42 | - loop carried level dependence | |
43 | - polyhedron dependence | |
44 | or with the chains of recurrences based representation, | |
b8698a0f L |
45 | |
46 | - to define a knowledge base for storing the data dependence | |
56cf8686 | 47 | information, |
b8698a0f | 48 | |
56cf8686 | 49 | - to define an interface to access this data. |
b8698a0f L |
50 | |
51 | ||
56cf8686 | 52 | Definitions: |
b8698a0f | 53 | |
56cf8686 SP |
54 | - subscript: given two array accesses a subscript is the tuple |
55 | composed of the access functions for a given dimension. Example: | |
56 | Given A[f1][f2][f3] and B[g1][g2][g3], there are three subscripts: | |
57 | (f1, g1), (f2, g2), (f3, g3). | |
58 | ||
59 | - Diophantine equation: an equation whose coefficients and | |
b8698a0f | 60 | solutions are integer constants, for example the equation |
56cf8686 SP |
61 | | 3*x + 2*y = 1 |
62 | has an integer solution x = 1 and y = -1. | |
b8698a0f | 63 | |
56cf8686 | 64 | References: |
b8698a0f | 65 | |
56cf8686 SP |
66 | - "Advanced Compilation for High Performance Computing" by Randy |
67 | Allen and Ken Kennedy. | |
b8698a0f L |
68 | http://citeseer.ist.psu.edu/goff91practical.html |
69 | ||
70 | - "Loop Transformations for Restructuring Compilers - The Foundations" | |
56cf8686 SP |
71 | by Utpal Banerjee. |
72 | ||
b8698a0f | 73 | |
56cf8686 SP |
74 | */ |
75 | ||
76 | #include "config.h" | |
77 | #include "system.h" | |
78 | #include "coretypes.h" | |
cf2d1b38 | 79 | #include "tree.h" |
cf835838 | 80 | #include "gimple-pretty-print.h" |
442b4905 | 81 | #include "gimple.h" |
5be5c238 | 82 | #include "gimple-iterator.h" |
e28030cf | 83 | #include "tree-ssa-loop-niter.h" |
442b4905 | 84 | #include "tree-ssa-loop.h" |
7a300452 | 85 | #include "tree-ssa.h" |
56cf8686 | 86 | #include "cfgloop.h" |
56cf8686 SP |
87 | #include "tree-data-ref.h" |
88 | #include "tree-scalar-evolution.h" | |
7ee2468b | 89 | #include "dumpfile.h" |
946e1bc7 | 90 | #include "langhooks.h" |
02f5d6c5 | 91 | #include "tree-affine.h" |
3881dee9 | 92 | #include "params.h" |
56cf8686 | 93 | |
0ff4040e SP |
94 | static struct datadep_stats |
95 | { | |
96 | int num_dependence_tests; | |
97 | int num_dependence_dependent; | |
98 | int num_dependence_independent; | |
99 | int num_dependence_undetermined; | |
100 | ||
101 | int num_subscript_tests; | |
102 | int num_subscript_undetermined; | |
103 | int num_same_subscript_function; | |
104 | ||
105 | int num_ziv; | |
106 | int num_ziv_independent; | |
107 | int num_ziv_dependent; | |
108 | int num_ziv_unimplemented; | |
109 | ||
110 | int num_siv; | |
111 | int num_siv_independent; | |
112 | int num_siv_dependent; | |
113 | int num_siv_unimplemented; | |
114 | ||
115 | int num_miv; | |
116 | int num_miv_independent; | |
117 | int num_miv_dependent; | |
118 | int num_miv_unimplemented; | |
119 | } dependence_stats; | |
120 | ||
ba42e045 SP |
121 | static bool subscript_dependence_tester_1 (struct data_dependence_relation *, |
122 | struct data_reference *, | |
da9a21f4 SP |
123 | struct data_reference *, |
124 | struct loop *); | |
56cf8686 SP |
125 | /* Returns true iff A divides B. */ |
126 | ||
b8698a0f | 127 | static inline bool |
ed7a4b4b | 128 | tree_fold_divides_p (const_tree a, const_tree b) |
56cf8686 | 129 | { |
b73a6056 RS |
130 | gcc_assert (TREE_CODE (a) == INTEGER_CST); |
131 | gcc_assert (TREE_CODE (b) == INTEGER_CST); | |
d35936ab | 132 | return integer_zerop (int_const_binop (TRUNC_MOD_EXPR, b, a)); |
56cf8686 SP |
133 | } |
134 | ||
86df10e3 SP |
135 | /* Returns true iff A divides B. */ |
136 | ||
b8698a0f | 137 | static inline bool |
86df10e3 SP |
138 | int_divides_p (int a, int b) |
139 | { | |
140 | return ((b % a) == 0); | |
56cf8686 SP |
141 | } |
142 | ||
143 | \f | |
144 | ||
b8698a0f | 145 | /* Dump into FILE all the data references from DATAREFS. */ |
56cf8686 | 146 | |
aeb83f09 | 147 | static void |
9771b263 | 148 | dump_data_references (FILE *file, vec<data_reference_p> datarefs) |
56cf8686 SP |
149 | { |
150 | unsigned int i; | |
ebf78a47 SP |
151 | struct data_reference *dr; |
152 | ||
9771b263 | 153 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
ebf78a47 | 154 | dump_data_reference (file, dr); |
56cf8686 SP |
155 | } |
156 | ||
7b3b6ae4 LC |
157 | /* Unified dump into FILE all the data references from DATAREFS. */ |
158 | ||
159 | DEBUG_FUNCTION void | |
160 | debug (vec<data_reference_p> &ref) | |
161 | { | |
162 | dump_data_references (stderr, ref); | |
163 | } | |
164 | ||
165 | DEBUG_FUNCTION void | |
166 | debug (vec<data_reference_p> *ptr) | |
167 | { | |
168 | if (ptr) | |
169 | debug (*ptr); | |
170 | else | |
171 | fprintf (stderr, "<nil>\n"); | |
172 | } | |
173 | ||
174 | ||
b8698a0f | 175 | /* Dump into STDERR all the data references from DATAREFS. */ |
a37d995a | 176 | |
24e47c76 | 177 | DEBUG_FUNCTION void |
9771b263 | 178 | debug_data_references (vec<data_reference_p> datarefs) |
a37d995a SP |
179 | { |
180 | dump_data_references (stderr, datarefs); | |
181 | } | |
182 | ||
a37d995a SP |
183 | /* Print to STDERR the data_reference DR. */ |
184 | ||
24e47c76 | 185 | DEBUG_FUNCTION void |
a37d995a SP |
186 | debug_data_reference (struct data_reference *dr) |
187 | { | |
188 | dump_data_reference (stderr, dr); | |
189 | } | |
190 | ||
56cf8686 SP |
191 | /* Dump function for a DATA_REFERENCE structure. */ |
192 | ||
b8698a0f L |
193 | void |
194 | dump_data_reference (FILE *outf, | |
56cf8686 SP |
195 | struct data_reference *dr) |
196 | { | |
197 | unsigned int i; | |
b8698a0f | 198 | |
28c5db57 SP |
199 | fprintf (outf, "#(Data Ref: \n"); |
200 | fprintf (outf, "# bb: %d \n", gimple_bb (DR_STMT (dr))->index); | |
201 | fprintf (outf, "# stmt: "); | |
726a989a | 202 | print_gimple_stmt (outf, DR_STMT (dr), 0, 0); |
03922af3 | 203 | fprintf (outf, "# ref: "); |
56cf8686 | 204 | print_generic_stmt (outf, DR_REF (dr), 0); |
03922af3 | 205 | fprintf (outf, "# base_object: "); |
86a07404 | 206 | print_generic_stmt (outf, DR_BASE_OBJECT (dr), 0); |
b8698a0f | 207 | |
56cf8686 SP |
208 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
209 | { | |
03922af3 | 210 | fprintf (outf, "# Access function %d: ", i); |
56cf8686 SP |
211 | print_generic_stmt (outf, DR_ACCESS_FN (dr, i), 0); |
212 | } | |
03922af3 | 213 | fprintf (outf, "#)\n"); |
56cf8686 SP |
214 | } |
215 | ||
7b3b6ae4 LC |
216 | /* Unified dump function for a DATA_REFERENCE structure. */ |
217 | ||
218 | DEBUG_FUNCTION void | |
219 | debug (data_reference &ref) | |
220 | { | |
221 | dump_data_reference (stderr, &ref); | |
222 | } | |
223 | ||
224 | DEBUG_FUNCTION void | |
225 | debug (data_reference *ptr) | |
226 | { | |
227 | if (ptr) | |
228 | debug (*ptr); | |
229 | else | |
230 | fprintf (stderr, "<nil>\n"); | |
231 | } | |
232 | ||
233 | ||
d93817c4 ZD |
234 | /* Dumps the affine function described by FN to the file OUTF. */ |
235 | ||
236 | static void | |
237 | dump_affine_function (FILE *outf, affine_fn fn) | |
238 | { | |
239 | unsigned i; | |
240 | tree coef; | |
241 | ||
9771b263 DN |
242 | print_generic_expr (outf, fn[0], TDF_SLIM); |
243 | for (i = 1; fn.iterate (i, &coef); i++) | |
d93817c4 ZD |
244 | { |
245 | fprintf (outf, " + "); | |
246 | print_generic_expr (outf, coef, TDF_SLIM); | |
247 | fprintf (outf, " * x_%u", i); | |
248 | } | |
249 | } | |
250 | ||
251 | /* Dumps the conflict function CF to the file OUTF. */ | |
252 | ||
253 | static void | |
254 | dump_conflict_function (FILE *outf, conflict_function *cf) | |
255 | { | |
256 | unsigned i; | |
257 | ||
258 | if (cf->n == NO_DEPENDENCE) | |
bcf1ef00 | 259 | fprintf (outf, "no dependence"); |
d93817c4 | 260 | else if (cf->n == NOT_KNOWN) |
bcf1ef00 | 261 | fprintf (outf, "not known"); |
d93817c4 ZD |
262 | else |
263 | { | |
264 | for (i = 0; i < cf->n; i++) | |
265 | { | |
bcf1ef00 RB |
266 | if (i != 0) |
267 | fprintf (outf, " "); | |
d93817c4 ZD |
268 | fprintf (outf, "["); |
269 | dump_affine_function (outf, cf->fns[i]); | |
bcf1ef00 | 270 | fprintf (outf, "]"); |
d93817c4 ZD |
271 | } |
272 | } | |
273 | } | |
274 | ||
86df10e3 SP |
275 | /* Dump function for a SUBSCRIPT structure. */ |
276 | ||
aeb83f09 | 277 | static void |
86df10e3 SP |
278 | dump_subscript (FILE *outf, struct subscript *subscript) |
279 | { | |
d93817c4 | 280 | conflict_function *cf = SUB_CONFLICTS_IN_A (subscript); |
86df10e3 SP |
281 | |
282 | fprintf (outf, "\n (subscript \n"); | |
283 | fprintf (outf, " iterations_that_access_an_element_twice_in_A: "); | |
d93817c4 ZD |
284 | dump_conflict_function (outf, cf); |
285 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
286 | { |
287 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
bcf1ef00 RB |
288 | fprintf (outf, "\n last_conflict: "); |
289 | print_generic_expr (outf, last_iteration, 0); | |
86df10e3 | 290 | } |
b8698a0f | 291 | |
d93817c4 | 292 | cf = SUB_CONFLICTS_IN_B (subscript); |
bcf1ef00 | 293 | fprintf (outf, "\n iterations_that_access_an_element_twice_in_B: "); |
d93817c4 ZD |
294 | dump_conflict_function (outf, cf); |
295 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
296 | { |
297 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
bcf1ef00 RB |
298 | fprintf (outf, "\n last_conflict: "); |
299 | print_generic_expr (outf, last_iteration, 0); | |
86df10e3 SP |
300 | } |
301 | ||
bcf1ef00 RB |
302 | fprintf (outf, "\n (Subscript distance: "); |
303 | print_generic_expr (outf, SUB_DISTANCE (subscript), 0); | |
304 | fprintf (outf, " ))\n"); | |
86df10e3 SP |
305 | } |
306 | ||
0ff4040e SP |
307 | /* Print the classic direction vector DIRV to OUTF. */ |
308 | ||
aeb83f09 | 309 | static void |
0ff4040e SP |
310 | print_direction_vector (FILE *outf, |
311 | lambda_vector dirv, | |
312 | int length) | |
313 | { | |
314 | int eq; | |
315 | ||
316 | for (eq = 0; eq < length; eq++) | |
317 | { | |
81f40b79 ILT |
318 | enum data_dependence_direction dir = ((enum data_dependence_direction) |
319 | dirv[eq]); | |
0ff4040e SP |
320 | |
321 | switch (dir) | |
322 | { | |
323 | case dir_positive: | |
324 | fprintf (outf, " +"); | |
325 | break; | |
326 | case dir_negative: | |
327 | fprintf (outf, " -"); | |
328 | break; | |
329 | case dir_equal: | |
330 | fprintf (outf, " ="); | |
331 | break; | |
332 | case dir_positive_or_equal: | |
333 | fprintf (outf, " +="); | |
334 | break; | |
335 | case dir_positive_or_negative: | |
336 | fprintf (outf, " +-"); | |
337 | break; | |
338 | case dir_negative_or_equal: | |
339 | fprintf (outf, " -="); | |
340 | break; | |
341 | case dir_star: | |
342 | fprintf (outf, " *"); | |
343 | break; | |
344 | default: | |
345 | fprintf (outf, "indep"); | |
346 | break; | |
347 | } | |
348 | } | |
349 | fprintf (outf, "\n"); | |
350 | } | |
351 | ||
ba42e045 SP |
352 | /* Print a vector of direction vectors. */ |
353 | ||
aeb83f09 | 354 | static void |
9771b263 | 355 | print_dir_vectors (FILE *outf, vec<lambda_vector> dir_vects, |
ba42e045 SP |
356 | int length) |
357 | { | |
358 | unsigned j; | |
359 | lambda_vector v; | |
360 | ||
9771b263 | 361 | FOR_EACH_VEC_ELT (dir_vects, j, v) |
ba42e045 SP |
362 | print_direction_vector (outf, v, length); |
363 | } | |
364 | ||
b305e3da SP |
365 | /* Print out a vector VEC of length N to OUTFILE. */ |
366 | ||
367 | static inline void | |
368 | print_lambda_vector (FILE * outfile, lambda_vector vector, int n) | |
369 | { | |
370 | int i; | |
371 | ||
372 | for (i = 0; i < n; i++) | |
373 | fprintf (outfile, "%3d ", vector[i]); | |
374 | fprintf (outfile, "\n"); | |
375 | } | |
376 | ||
ba42e045 SP |
377 | /* Print a vector of distance vectors. */ |
378 | ||
aeb83f09 | 379 | static void |
9771b263 | 380 | print_dist_vectors (FILE *outf, vec<lambda_vector> dist_vects, |
aeb83f09 | 381 | int length) |
ba42e045 SP |
382 | { |
383 | unsigned j; | |
384 | lambda_vector v; | |
385 | ||
9771b263 | 386 | FOR_EACH_VEC_ELT (dist_vects, j, v) |
ba42e045 SP |
387 | print_lambda_vector (outf, v, length); |
388 | } | |
389 | ||
56cf8686 SP |
390 | /* Dump function for a DATA_DEPENDENCE_RELATION structure. */ |
391 | ||
aeb83f09 | 392 | static void |
b8698a0f | 393 | dump_data_dependence_relation (FILE *outf, |
56cf8686 SP |
394 | struct data_dependence_relation *ddr) |
395 | { | |
56cf8686 | 396 | struct data_reference *dra, *drb; |
86df10e3 | 397 | |
86df10e3 | 398 | fprintf (outf, "(Data Dep: \n"); |
dea61d92 | 399 | |
ed2024ba MJ |
400 | if (!ddr || DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) |
401 | { | |
b61b1f17 MM |
402 | if (ddr) |
403 | { | |
404 | dra = DDR_A (ddr); | |
405 | drb = DDR_B (ddr); | |
406 | if (dra) | |
407 | dump_data_reference (outf, dra); | |
408 | else | |
409 | fprintf (outf, " (nil)\n"); | |
410 | if (drb) | |
411 | dump_data_reference (outf, drb); | |
412 | else | |
413 | fprintf (outf, " (nil)\n"); | |
414 | } | |
ed2024ba MJ |
415 | fprintf (outf, " (don't know)\n)\n"); |
416 | return; | |
417 | } | |
418 | ||
419 | dra = DDR_A (ddr); | |
420 | drb = DDR_B (ddr); | |
dea61d92 SP |
421 | dump_data_reference (outf, dra); |
422 | dump_data_reference (outf, drb); | |
423 | ||
ed2024ba | 424 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
56cf8686 | 425 | fprintf (outf, " (no dependence)\n"); |
b8698a0f | 426 | |
86df10e3 | 427 | else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
56cf8686 | 428 | { |
86df10e3 | 429 | unsigned int i; |
ba42e045 | 430 | struct loop *loopi; |
304afda6 | 431 | |
56cf8686 SP |
432 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
433 | { | |
56cf8686 SP |
434 | fprintf (outf, " access_fn_A: "); |
435 | print_generic_stmt (outf, DR_ACCESS_FN (dra, i), 0); | |
436 | fprintf (outf, " access_fn_B: "); | |
437 | print_generic_stmt (outf, DR_ACCESS_FN (drb, i), 0); | |
86df10e3 | 438 | dump_subscript (outf, DDR_SUBSCRIPT (ddr, i)); |
56cf8686 | 439 | } |
304afda6 | 440 | |
3d8864c0 | 441 | fprintf (outf, " inner loop index: %d\n", DDR_INNER_LOOP (ddr)); |
ba42e045 | 442 | fprintf (outf, " loop nest: ("); |
9771b263 | 443 | FOR_EACH_VEC_ELT (DDR_LOOP_NEST (ddr), i, loopi) |
ba42e045 SP |
444 | fprintf (outf, "%d ", loopi->num); |
445 | fprintf (outf, ")\n"); | |
446 | ||
304afda6 | 447 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) |
56cf8686 | 448 | { |
304afda6 SP |
449 | fprintf (outf, " distance_vector: "); |
450 | print_lambda_vector (outf, DDR_DIST_VECT (ddr, i), | |
ba42e045 | 451 | DDR_NB_LOOPS (ddr)); |
86df10e3 | 452 | } |
304afda6 SP |
453 | |
454 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
86df10e3 | 455 | { |
304afda6 | 456 | fprintf (outf, " direction_vector: "); |
0ff4040e | 457 | print_direction_vector (outf, DDR_DIR_VECT (ddr, i), |
ba42e045 | 458 | DDR_NB_LOOPS (ddr)); |
56cf8686 | 459 | } |
56cf8686 SP |
460 | } |
461 | ||
462 | fprintf (outf, ")\n"); | |
463 | } | |
464 | ||
aeb83f09 | 465 | /* Debug version. */ |
56cf8686 | 466 | |
aeb83f09 RG |
467 | DEBUG_FUNCTION void |
468 | debug_data_dependence_relation (struct data_dependence_relation *ddr) | |
56cf8686 | 469 | { |
aeb83f09 RG |
470 | dump_data_dependence_relation (stderr, ddr); |
471 | } | |
b8698a0f | 472 | |
aeb83f09 | 473 | /* Dump into FILE all the dependence relations from DDRS. */ |
b8698a0f | 474 | |
aeb83f09 RG |
475 | void |
476 | dump_data_dependence_relations (FILE *file, | |
9771b263 | 477 | vec<ddr_p> ddrs) |
aeb83f09 RG |
478 | { |
479 | unsigned int i; | |
480 | struct data_dependence_relation *ddr; | |
b8698a0f | 481 | |
9771b263 | 482 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
aeb83f09 RG |
483 | dump_data_dependence_relation (file, ddr); |
484 | } | |
b8698a0f | 485 | |
7b3b6ae4 LC |
486 | DEBUG_FUNCTION void |
487 | debug (vec<ddr_p> &ref) | |
488 | { | |
489 | dump_data_dependence_relations (stderr, ref); | |
490 | } | |
491 | ||
492 | DEBUG_FUNCTION void | |
493 | debug (vec<ddr_p> *ptr) | |
494 | { | |
495 | if (ptr) | |
496 | debug (*ptr); | |
497 | else | |
498 | fprintf (stderr, "<nil>\n"); | |
499 | } | |
500 | ||
501 | ||
aeb83f09 | 502 | /* Dump to STDERR all the dependence relations from DDRS. */ |
b8698a0f | 503 | |
aeb83f09 | 504 | DEBUG_FUNCTION void |
9771b263 | 505 | debug_data_dependence_relations (vec<ddr_p> ddrs) |
aeb83f09 RG |
506 | { |
507 | dump_data_dependence_relations (stderr, ddrs); | |
56cf8686 SP |
508 | } |
509 | ||
86df10e3 SP |
510 | /* Dumps the distance and direction vectors in FILE. DDRS contains |
511 | the dependence relations, and VECT_SIZE is the size of the | |
512 | dependence vectors, or in other words the number of loops in the | |
513 | considered nest. */ | |
514 | ||
aeb83f09 | 515 | static void |
9771b263 | 516 | dump_dist_dir_vectors (FILE *file, vec<ddr_p> ddrs) |
86df10e3 | 517 | { |
304afda6 | 518 | unsigned int i, j; |
ebf78a47 SP |
519 | struct data_dependence_relation *ddr; |
520 | lambda_vector v; | |
86df10e3 | 521 | |
9771b263 | 522 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
ebf78a47 SP |
523 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_AFFINE_P (ddr)) |
524 | { | |
9771b263 | 525 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), j, v) |
ebf78a47 SP |
526 | { |
527 | fprintf (file, "DISTANCE_V ("); | |
528 | print_lambda_vector (file, v, DDR_NB_LOOPS (ddr)); | |
529 | fprintf (file, ")\n"); | |
530 | } | |
531 | ||
9771b263 | 532 | FOR_EACH_VEC_ELT (DDR_DIR_VECTS (ddr), j, v) |
ebf78a47 SP |
533 | { |
534 | fprintf (file, "DIRECTION_V ("); | |
535 | print_direction_vector (file, v, DDR_NB_LOOPS (ddr)); | |
536 | fprintf (file, ")\n"); | |
537 | } | |
538 | } | |
304afda6 | 539 | |
86df10e3 SP |
540 | fprintf (file, "\n\n"); |
541 | } | |
542 | ||
543 | /* Dumps the data dependence relations DDRS in FILE. */ | |
544 | ||
aeb83f09 | 545 | static void |
9771b263 | 546 | dump_ddrs (FILE *file, vec<ddr_p> ddrs) |
86df10e3 SP |
547 | { |
548 | unsigned int i; | |
ebf78a47 SP |
549 | struct data_dependence_relation *ddr; |
550 | ||
9771b263 | 551 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
ebf78a47 | 552 | dump_data_dependence_relation (file, ddr); |
86df10e3 | 553 | |
86df10e3 SP |
554 | fprintf (file, "\n\n"); |
555 | } | |
556 | ||
aeb83f09 | 557 | DEBUG_FUNCTION void |
9771b263 | 558 | debug_ddrs (vec<ddr_p> ddrs) |
aeb83f09 RG |
559 | { |
560 | dump_ddrs (stderr, ddrs); | |
561 | } | |
562 | ||
726a989a RB |
563 | /* Helper function for split_constant_offset. Expresses OP0 CODE OP1 |
564 | (the type of the result is TYPE) as VAR + OFF, where OFF is a nonzero | |
565 | constant of type ssizetype, and returns true. If we cannot do this | |
566 | with OFF nonzero, OFF and VAR are set to NULL_TREE instead and false | |
567 | is returned. */ | |
86a07404 | 568 | |
726a989a RB |
569 | static bool |
570 | split_constant_offset_1 (tree type, tree op0, enum tree_code code, tree op1, | |
571 | tree *var, tree *off) | |
86a07404 | 572 | { |
3cb960c7 ZD |
573 | tree var0, var1; |
574 | tree off0, off1; | |
726a989a | 575 | enum tree_code ocode = code; |
86a07404 | 576 | |
726a989a RB |
577 | *var = NULL_TREE; |
578 | *off = NULL_TREE; | |
86a07404 | 579 | |
5be014d5 | 580 | switch (code) |
86a07404 | 581 | { |
3cb960c7 ZD |
582 | case INTEGER_CST: |
583 | *var = build_int_cst (type, 0); | |
726a989a RB |
584 | *off = fold_convert (ssizetype, op0); |
585 | return true; | |
86a07404 | 586 | |
5be014d5 | 587 | case POINTER_PLUS_EXPR: |
726a989a | 588 | ocode = PLUS_EXPR; |
5be014d5 | 589 | /* FALLTHROUGH */ |
3cb960c7 ZD |
590 | case PLUS_EXPR: |
591 | case MINUS_EXPR: | |
726a989a RB |
592 | split_constant_offset (op0, &var0, &off0); |
593 | split_constant_offset (op1, &var1, &off1); | |
594 | *var = fold_build2 (code, type, var0, var1); | |
595 | *off = size_binop (ocode, off0, off1); | |
596 | return true; | |
86a07404 | 597 | |
86a07404 | 598 | case MULT_EXPR: |
726a989a RB |
599 | if (TREE_CODE (op1) != INTEGER_CST) |
600 | return false; | |
3cb960c7 | 601 | |
726a989a RB |
602 | split_constant_offset (op0, &var0, &off0); |
603 | *var = fold_build2 (MULT_EXPR, type, var0, op1); | |
604 | *off = size_binop (MULT_EXPR, off0, fold_convert (ssizetype, op1)); | |
605 | return true; | |
86a07404 | 606 | |
3cb960c7 ZD |
607 | case ADDR_EXPR: |
608 | { | |
726a989a | 609 | tree base, poffset; |
3cb960c7 ZD |
610 | HOST_WIDE_INT pbitsize, pbitpos; |
611 | enum machine_mode pmode; | |
612 | int punsignedp, pvolatilep; | |
86a07404 | 613 | |
da4b6efc | 614 | op0 = TREE_OPERAND (op0, 0); |
726a989a | 615 | base = get_inner_reference (op0, &pbitsize, &pbitpos, &poffset, |
3cb960c7 | 616 | &pmode, &punsignedp, &pvolatilep, false); |
86a07404 | 617 | |
3cb960c7 | 618 | if (pbitpos % BITS_PER_UNIT != 0) |
726a989a | 619 | return false; |
3cb960c7 ZD |
620 | base = build_fold_addr_expr (base); |
621 | off0 = ssize_int (pbitpos / BITS_PER_UNIT); | |
86a07404 | 622 | |
3cb960c7 ZD |
623 | if (poffset) |
624 | { | |
625 | split_constant_offset (poffset, &poffset, &off1); | |
626 | off0 = size_binop (PLUS_EXPR, off0, off1); | |
36ad7922 | 627 | if (POINTER_TYPE_P (TREE_TYPE (base))) |
5d49b6a7 | 628 | base = fold_build_pointer_plus (base, poffset); |
36ad7922 JJ |
629 | else |
630 | base = fold_build2 (PLUS_EXPR, TREE_TYPE (base), base, | |
631 | fold_convert (TREE_TYPE (base), poffset)); | |
3cb960c7 ZD |
632 | } |
633 | ||
6481b879 JJ |
634 | var0 = fold_convert (type, base); |
635 | ||
636 | /* If variable length types are involved, punt, otherwise casts | |
637 | might be converted into ARRAY_REFs in gimplify_conversion. | |
638 | To compute that ARRAY_REF's element size TYPE_SIZE_UNIT, which | |
639 | possibly no longer appears in current GIMPLE, might resurface. | |
640 | This perhaps could run | |
1a87cf0c | 641 | if (CONVERT_EXPR_P (var0)) |
6481b879 JJ |
642 | { |
643 | gimplify_conversion (&var0); | |
644 | // Attempt to fill in any within var0 found ARRAY_REF's | |
645 | // element size from corresponding op embedded ARRAY_REF, | |
646 | // if unsuccessful, just punt. | |
647 | } */ | |
648 | while (POINTER_TYPE_P (type)) | |
649 | type = TREE_TYPE (type); | |
650 | if (int_size_in_bytes (type) < 0) | |
726a989a | 651 | return false; |
6481b879 JJ |
652 | |
653 | *var = var0; | |
3cb960c7 | 654 | *off = off0; |
726a989a | 655 | return true; |
3cb960c7 | 656 | } |
86a07404 | 657 | |
06cb4f79 JS |
658 | case SSA_NAME: |
659 | { | |
726a989a RB |
660 | gimple def_stmt = SSA_NAME_DEF_STMT (op0); |
661 | enum tree_code subcode; | |
06cb4f79 | 662 | |
726a989a RB |
663 | if (gimple_code (def_stmt) != GIMPLE_ASSIGN) |
664 | return false; | |
665 | ||
666 | var0 = gimple_assign_rhs1 (def_stmt); | |
667 | subcode = gimple_assign_rhs_code (def_stmt); | |
668 | var1 = gimple_assign_rhs2 (def_stmt); | |
669 | ||
670 | return split_constant_offset_1 (type, var0, subcode, var1, var, off); | |
06cb4f79 | 671 | } |
b61b1f17 MM |
672 | CASE_CONVERT: |
673 | { | |
674 | /* We must not introduce undefined overflow, and we must not change the value. | |
675 | Hence we're okay if the inner type doesn't overflow to start with | |
676 | (pointer or signed), the outer type also is an integer or pointer | |
677 | and the outer precision is at least as large as the inner. */ | |
678 | tree itype = TREE_TYPE (op0); | |
679 | if ((POINTER_TYPE_P (itype) | |
680 | || (INTEGRAL_TYPE_P (itype) && TYPE_OVERFLOW_UNDEFINED (itype))) | |
681 | && TYPE_PRECISION (type) >= TYPE_PRECISION (itype) | |
682 | && (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type))) | |
683 | { | |
684 | split_constant_offset (op0, &var0, off); | |
685 | *var = fold_convert (type, var0); | |
686 | return true; | |
687 | } | |
688 | return false; | |
689 | } | |
06cb4f79 | 690 | |
86a07404 | 691 | default: |
726a989a | 692 | return false; |
86a07404 | 693 | } |
726a989a RB |
694 | } |
695 | ||
696 | /* Expresses EXP as VAR + OFF, where off is a constant. The type of OFF | |
697 | will be ssizetype. */ | |
698 | ||
699 | void | |
700 | split_constant_offset (tree exp, tree *var, tree *off) | |
701 | { | |
702 | tree type = TREE_TYPE (exp), otype, op0, op1, e, o; | |
703 | enum tree_code code; | |
86a07404 | 704 | |
726a989a | 705 | *var = exp; |
3cb960c7 | 706 | *off = ssize_int (0); |
726a989a RB |
707 | STRIP_NOPS (exp); |
708 | ||
ffd78b30 RG |
709 | if (tree_is_chrec (exp) |
710 | || get_gimple_rhs_class (TREE_CODE (exp)) == GIMPLE_TERNARY_RHS) | |
726a989a RB |
711 | return; |
712 | ||
713 | otype = TREE_TYPE (exp); | |
714 | code = TREE_CODE (exp); | |
715 | extract_ops_from_tree (exp, &code, &op0, &op1); | |
716 | if (split_constant_offset_1 (otype, op0, code, op1, &e, &o)) | |
717 | { | |
718 | *var = fold_convert (type, e); | |
719 | *off = o; | |
720 | } | |
86a07404 IR |
721 | } |
722 | ||
3cb960c7 ZD |
723 | /* Returns the address ADDR of an object in a canonical shape (without nop |
724 | casts, and with type of pointer to the object). */ | |
86a07404 IR |
725 | |
726 | static tree | |
3cb960c7 | 727 | canonicalize_base_object_address (tree addr) |
86a07404 | 728 | { |
bbc8a8dc ZD |
729 | tree orig = addr; |
730 | ||
3cb960c7 | 731 | STRIP_NOPS (addr); |
86a07404 | 732 | |
bbc8a8dc ZD |
733 | /* The base address may be obtained by casting from integer, in that case |
734 | keep the cast. */ | |
735 | if (!POINTER_TYPE_P (TREE_TYPE (addr))) | |
736 | return orig; | |
737 | ||
3cb960c7 ZD |
738 | if (TREE_CODE (addr) != ADDR_EXPR) |
739 | return addr; | |
86a07404 | 740 | |
3cb960c7 | 741 | return build_fold_addr_expr (TREE_OPERAND (addr, 0)); |
86a07404 IR |
742 | } |
743 | ||
b8698a0f | 744 | /* Analyzes the behavior of the memory reference DR in the innermost loop or |
4e4452b6 | 745 | basic block that contains it. Returns true if analysis succeed or false |
a70d6342 | 746 | otherwise. */ |
86a07404 | 747 | |
3661e899 | 748 | bool |
4e4452b6 | 749 | dr_analyze_innermost (struct data_reference *dr, struct loop *nest) |
86a07404 | 750 | { |
726a989a | 751 | gimple stmt = DR_STMT (dr); |
3cb960c7 ZD |
752 | struct loop *loop = loop_containing_stmt (stmt); |
753 | tree ref = DR_REF (dr); | |
86a07404 | 754 | HOST_WIDE_INT pbitsize, pbitpos; |
3cb960c7 | 755 | tree base, poffset; |
86a07404 IR |
756 | enum machine_mode pmode; |
757 | int punsignedp, pvolatilep; | |
3cb960c7 ZD |
758 | affine_iv base_iv, offset_iv; |
759 | tree init, dinit, step; | |
a70d6342 | 760 | bool in_loop = (loop && loop->num); |
3cb960c7 ZD |
761 | |
762 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
763 | fprintf (dump_file, "analyze_innermost: "); | |
86a07404 | 764 | |
3cb960c7 ZD |
765 | base = get_inner_reference (ref, &pbitsize, &pbitpos, &poffset, |
766 | &pmode, &punsignedp, &pvolatilep, false); | |
767 | gcc_assert (base != NULL_TREE); | |
86a07404 | 768 | |
3cb960c7 | 769 | if (pbitpos % BITS_PER_UNIT != 0) |
86a07404 | 770 | { |
3cb960c7 ZD |
771 | if (dump_file && (dump_flags & TDF_DETAILS)) |
772 | fprintf (dump_file, "failed: bit offset alignment.\n"); | |
3661e899 | 773 | return false; |
3cb960c7 | 774 | } |
86a07404 | 775 | |
70f34814 RG |
776 | if (TREE_CODE (base) == MEM_REF) |
777 | { | |
778 | if (!integer_zerop (TREE_OPERAND (base, 1))) | |
779 | { | |
673910d7 RG |
780 | double_int moff = mem_ref_offset (base); |
781 | tree mofft = double_int_to_tree (sizetype, moff); | |
70f34814 | 782 | if (!poffset) |
673910d7 | 783 | poffset = mofft; |
70f34814 | 784 | else |
673910d7 | 785 | poffset = size_binop (PLUS_EXPR, poffset, mofft); |
70f34814 RG |
786 | } |
787 | base = TREE_OPERAND (base, 0); | |
788 | } | |
789 | else | |
790 | base = build_fold_addr_expr (base); | |
4e4452b6 | 791 | |
a70d6342 | 792 | if (in_loop) |
3cb960c7 | 793 | { |
b8698a0f | 794 | if (!simple_iv (loop, loop_containing_stmt (stmt), base, &base_iv, |
319e6439 | 795 | nest ? true : false)) |
a70d6342 | 796 | { |
4e4452b6 IR |
797 | if (nest) |
798 | { | |
799 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
800 | fprintf (dump_file, "failed: evolution of base is not" | |
801 | " affine.\n"); | |
802 | return false; | |
803 | } | |
804 | else | |
805 | { | |
806 | base_iv.base = base; | |
807 | base_iv.step = ssize_int (0); | |
808 | base_iv.no_overflow = true; | |
809 | } | |
a70d6342 IR |
810 | } |
811 | } | |
812 | else | |
813 | { | |
814 | base_iv.base = base; | |
815 | base_iv.step = ssize_int (0); | |
816 | base_iv.no_overflow = true; | |
3cb960c7 | 817 | } |
a70d6342 | 818 | |
24adb18f | 819 | if (!poffset) |
3cb960c7 ZD |
820 | { |
821 | offset_iv.base = ssize_int (0); | |
822 | offset_iv.step = ssize_int (0); | |
823 | } | |
24adb18f | 824 | else |
3cb960c7 | 825 | { |
24adb18f IR |
826 | if (!in_loop) |
827 | { | |
828 | offset_iv.base = poffset; | |
829 | offset_iv.step = ssize_int (0); | |
830 | } | |
831 | else if (!simple_iv (loop, loop_containing_stmt (stmt), | |
319e6439 RG |
832 | poffset, &offset_iv, |
833 | nest ? true : false)) | |
24adb18f | 834 | { |
4e4452b6 IR |
835 | if (nest) |
836 | { | |
837 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
838 | fprintf (dump_file, "failed: evolution of offset is not" | |
839 | " affine.\n"); | |
840 | return false; | |
841 | } | |
842 | else | |
843 | { | |
844 | offset_iv.base = poffset; | |
845 | offset_iv.step = ssize_int (0); | |
846 | } | |
24adb18f | 847 | } |
3cb960c7 | 848 | } |
86a07404 | 849 | |
3cb960c7 ZD |
850 | init = ssize_int (pbitpos / BITS_PER_UNIT); |
851 | split_constant_offset (base_iv.base, &base_iv.base, &dinit); | |
852 | init = size_binop (PLUS_EXPR, init, dinit); | |
853 | split_constant_offset (offset_iv.base, &offset_iv.base, &dinit); | |
854 | init = size_binop (PLUS_EXPR, init, dinit); | |
86a07404 | 855 | |
3cb960c7 ZD |
856 | step = size_binop (PLUS_EXPR, |
857 | fold_convert (ssizetype, base_iv.step), | |
858 | fold_convert (ssizetype, offset_iv.step)); | |
86a07404 | 859 | |
3cb960c7 | 860 | DR_BASE_ADDRESS (dr) = canonicalize_base_object_address (base_iv.base); |
86a07404 | 861 | |
3cb960c7 ZD |
862 | DR_OFFSET (dr) = fold_convert (ssizetype, offset_iv.base); |
863 | DR_INIT (dr) = init; | |
864 | DR_STEP (dr) = step; | |
86a07404 | 865 | |
3cb960c7 | 866 | DR_ALIGNED_TO (dr) = size_int (highest_pow2_factor (offset_iv.base)); |
86a07404 | 867 | |
3cb960c7 ZD |
868 | if (dump_file && (dump_flags & TDF_DETAILS)) |
869 | fprintf (dump_file, "success.\n"); | |
3661e899 TB |
870 | |
871 | return true; | |
3cb960c7 | 872 | } |
86a07404 | 873 | |
3cb960c7 | 874 | /* Determines the base object and the list of indices of memory reference |
5c640e29 | 875 | DR, analyzed in LOOP and instantiated in loop nest NEST. */ |
86a07404 | 876 | |
3cb960c7 | 877 | static void |
5c640e29 | 878 | dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop) |
3cb960c7 | 879 | { |
6e1aa848 | 880 | vec<tree> access_fns = vNULL; |
c4ddde1b | 881 | tree ref, op; |
9fcb758b RG |
882 | tree base, off, access_fn; |
883 | basic_block before_loop; | |
b8698a0f | 884 | |
9fcb758b RG |
885 | /* If analyzing a basic-block there are no indices to analyze |
886 | and thus no access functions. */ | |
02f5d6c5 RG |
887 | if (!nest) |
888 | { | |
9fcb758b | 889 | DR_BASE_OBJECT (dr) = DR_REF (dr); |
9771b263 | 890 | DR_ACCESS_FNS (dr).create (0); |
02f5d6c5 RG |
891 | return; |
892 | } | |
893 | ||
c4ddde1b | 894 | ref = DR_REF (dr); |
02f5d6c5 | 895 | before_loop = block_before_loop (nest); |
b8698a0f | 896 | |
9fcb758b RG |
897 | /* REALPART_EXPR and IMAGPART_EXPR can be handled like accesses |
898 | into a two element array with a constant index. The base is | |
899 | then just the immediate underlying object. */ | |
900 | if (TREE_CODE (ref) == REALPART_EXPR) | |
901 | { | |
902 | ref = TREE_OPERAND (ref, 0); | |
9771b263 | 903 | access_fns.safe_push (integer_zero_node); |
9fcb758b RG |
904 | } |
905 | else if (TREE_CODE (ref) == IMAGPART_EXPR) | |
906 | { | |
907 | ref = TREE_OPERAND (ref, 0); | |
9771b263 | 908 | access_fns.safe_push (integer_one_node); |
9fcb758b RG |
909 | } |
910 | ||
b8324815 | 911 | /* Analyze access functions of dimensions we know to be independent. */ |
c4ddde1b | 912 | while (handled_component_p (ref)) |
86a07404 | 913 | { |
c4ddde1b | 914 | if (TREE_CODE (ref) == ARRAY_REF) |
86a07404 | 915 | { |
c4ddde1b | 916 | op = TREE_OPERAND (ref, 1); |
02f5d6c5 RG |
917 | access_fn = analyze_scalar_evolution (loop, op); |
918 | access_fn = instantiate_scev (before_loop, loop, access_fn); | |
9771b263 | 919 | access_fns.safe_push (access_fn); |
b8324815 | 920 | } |
c4ddde1b RG |
921 | else if (TREE_CODE (ref) == COMPONENT_REF |
922 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (ref, 0))) == RECORD_TYPE) | |
923 | { | |
924 | /* For COMPONENT_REFs of records (but not unions!) use the | |
925 | FIELD_DECL offset as constant access function so we can | |
926 | disambiguate a[i].f1 and a[i].f2. */ | |
927 | tree off = component_ref_field_offset (ref); | |
928 | off = size_binop (PLUS_EXPR, | |
929 | size_binop (MULT_EXPR, | |
930 | fold_convert (bitsizetype, off), | |
931 | bitsize_int (BITS_PER_UNIT)), | |
932 | DECL_FIELD_BIT_OFFSET (TREE_OPERAND (ref, 1))); | |
9771b263 | 933 | access_fns.safe_push (off); |
c4ddde1b RG |
934 | } |
935 | else | |
936 | /* If we have an unhandled component we could not translate | |
937 | to an access function stop analyzing. We have determined | |
938 | our base object in this case. */ | |
939 | break; | |
b8698a0f | 940 | |
c4ddde1b | 941 | ref = TREE_OPERAND (ref, 0); |
86a07404 IR |
942 | } |
943 | ||
8c330caa RG |
944 | /* If the address operand of a MEM_REF base has an evolution in the |
945 | analyzed nest, add it as an additional independent access-function. */ | |
c4ddde1b | 946 | if (TREE_CODE (ref) == MEM_REF) |
86a07404 | 947 | { |
c4ddde1b | 948 | op = TREE_OPERAND (ref, 0); |
3cb960c7 | 949 | access_fn = analyze_scalar_evolution (loop, op); |
a213b219 | 950 | access_fn = instantiate_scev (before_loop, loop, access_fn); |
8c330caa | 951 | if (TREE_CODE (access_fn) == POLYNOMIAL_CHREC) |
2946bd34 | 952 | { |
0a500dd3 | 953 | tree orig_type; |
c4ddde1b | 954 | tree memoff = TREE_OPERAND (ref, 1); |
8c330caa | 955 | base = initial_condition (access_fn); |
0a500dd3 RG |
956 | orig_type = TREE_TYPE (base); |
957 | STRIP_USELESS_TYPE_CONVERSION (base); | |
8c330caa RG |
958 | split_constant_offset (base, &base, &off); |
959 | /* Fold the MEM_REF offset into the evolutions initial | |
960 | value to make more bases comparable. */ | |
c4ddde1b | 961 | if (!integer_zerop (memoff)) |
8c330caa RG |
962 | { |
963 | off = size_binop (PLUS_EXPR, off, | |
c4ddde1b RG |
964 | fold_convert (ssizetype, memoff)); |
965 | memoff = build_int_cst (TREE_TYPE (memoff), 0); | |
8c330caa RG |
966 | } |
967 | access_fn = chrec_replace_initial_condition | |
0a500dd3 | 968 | (access_fn, fold_convert (orig_type, off)); |
c4ddde1b RG |
969 | /* ??? This is still not a suitable base object for |
970 | dr_may_alias_p - the base object needs to be an | |
971 | access that covers the object as whole. With | |
972 | an evolution in the pointer this cannot be | |
973 | guaranteed. | |
974 | As a band-aid, mark the access so we can special-case | |
975 | it in dr_may_alias_p. */ | |
976 | ref = fold_build2_loc (EXPR_LOCATION (ref), | |
977 | MEM_REF, TREE_TYPE (ref), | |
978 | base, memoff); | |
979 | DR_UNCONSTRAINED_BASE (dr) = true; | |
9771b263 | 980 | access_fns.safe_push (access_fn); |
2946bd34 | 981 | } |
86a07404 | 982 | } |
c4ddde1b RG |
983 | else if (DECL_P (ref)) |
984 | { | |
985 | /* Canonicalize DR_BASE_OBJECT to MEM_REF form. */ | |
986 | ref = build2 (MEM_REF, TREE_TYPE (ref), | |
987 | build_fold_addr_expr (ref), | |
988 | build_int_cst (reference_alias_ptr_type (ref), 0)); | |
989 | } | |
86a07404 | 990 | |
3cb960c7 ZD |
991 | DR_BASE_OBJECT (dr) = ref; |
992 | DR_ACCESS_FNS (dr) = access_fns; | |
86a07404 IR |
993 | } |
994 | ||
3cb960c7 | 995 | /* Extracts the alias analysis information from the memory reference DR. */ |
86a07404 | 996 | |
3cb960c7 ZD |
997 | static void |
998 | dr_analyze_alias (struct data_reference *dr) | |
86a07404 | 999 | { |
3cb960c7 | 1000 | tree ref = DR_REF (dr); |
5006671f RG |
1001 | tree base = get_base_address (ref), addr; |
1002 | ||
70f34814 RG |
1003 | if (INDIRECT_REF_P (base) |
1004 | || TREE_CODE (base) == MEM_REF) | |
3cb960c7 ZD |
1005 | { |
1006 | addr = TREE_OPERAND (base, 0); | |
1007 | if (TREE_CODE (addr) == SSA_NAME) | |
5006671f | 1008 | DR_PTR_INFO (dr) = SSA_NAME_PTR_INFO (addr); |
3cb960c7 | 1009 | } |
3cb960c7 | 1010 | } |
86a07404 | 1011 | |
3cb960c7 | 1012 | /* Frees data reference DR. */ |
8fdbc9c6 | 1013 | |
dea61d92 | 1014 | void |
8fdbc9c6 ZD |
1015 | free_data_ref (data_reference_p dr) |
1016 | { | |
9771b263 | 1017 | DR_ACCESS_FNS (dr).release (); |
8fdbc9c6 ZD |
1018 | free (dr); |
1019 | } | |
86a07404 | 1020 | |
3cb960c7 ZD |
1021 | /* Analyzes memory reference MEMREF accessed in STMT. The reference |
1022 | is read if IS_READ is true, write otherwise. Returns the | |
5c640e29 SP |
1023 | data_reference description of MEMREF. NEST is the outermost loop |
1024 | in which the reference should be instantiated, LOOP is the loop in | |
1025 | which the data reference should be analyzed. */ | |
86a07404 | 1026 | |
5417e022 | 1027 | struct data_reference * |
5c640e29 SP |
1028 | create_data_ref (loop_p nest, loop_p loop, tree memref, gimple stmt, |
1029 | bool is_read) | |
86a07404 | 1030 | { |
3cb960c7 | 1031 | struct data_reference *dr; |
0ff4040e | 1032 | |
3cb960c7 | 1033 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e | 1034 | { |
3cb960c7 ZD |
1035 | fprintf (dump_file, "Creating dr for "); |
1036 | print_generic_expr (dump_file, memref, TDF_SLIM); | |
1037 | fprintf (dump_file, "\n"); | |
0ff4040e | 1038 | } |
e2157b49 | 1039 | |
3cb960c7 ZD |
1040 | dr = XCNEW (struct data_reference); |
1041 | DR_STMT (dr) = stmt; | |
1042 | DR_REF (dr) = memref; | |
1043 | DR_IS_READ (dr) = is_read; | |
86a07404 | 1044 | |
4e4452b6 | 1045 | dr_analyze_innermost (dr, nest); |
5c640e29 | 1046 | dr_analyze_indices (dr, nest, loop); |
3cb960c7 | 1047 | dr_analyze_alias (dr); |
86a07404 IR |
1048 | |
1049 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1050 | { | |
b8324815 | 1051 | unsigned i; |
3cb960c7 | 1052 | fprintf (dump_file, "\tbase_address: "); |
86a07404 IR |
1053 | print_generic_expr (dump_file, DR_BASE_ADDRESS (dr), TDF_SLIM); |
1054 | fprintf (dump_file, "\n\toffset from base address: "); | |
1055 | print_generic_expr (dump_file, DR_OFFSET (dr), TDF_SLIM); | |
1056 | fprintf (dump_file, "\n\tconstant offset from base address: "); | |
1057 | print_generic_expr (dump_file, DR_INIT (dr), TDF_SLIM); | |
86a07404 IR |
1058 | fprintf (dump_file, "\n\tstep: "); |
1059 | print_generic_expr (dump_file, DR_STEP (dr), TDF_SLIM); | |
3cb960c7 ZD |
1060 | fprintf (dump_file, "\n\taligned to: "); |
1061 | print_generic_expr (dump_file, DR_ALIGNED_TO (dr), TDF_SLIM); | |
1062 | fprintf (dump_file, "\n\tbase_object: "); | |
1063 | print_generic_expr (dump_file, DR_BASE_OBJECT (dr), TDF_SLIM); | |
86a07404 | 1064 | fprintf (dump_file, "\n"); |
b8324815 RG |
1065 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
1066 | { | |
1067 | fprintf (dump_file, "\tAccess function %d: ", i); | |
1068 | print_generic_stmt (dump_file, DR_ACCESS_FN (dr, i), TDF_SLIM); | |
1069 | } | |
3cb960c7 ZD |
1070 | } |
1071 | ||
b8698a0f | 1072 | return dr; |
86a07404 IR |
1073 | } |
1074 | ||
bfe068c3 IR |
1075 | /* Check if OFFSET1 and OFFSET2 (DR_OFFSETs of some data-refs) are identical |
1076 | expressions. */ | |
1077 | static bool | |
1078 | dr_equal_offsets_p1 (tree offset1, tree offset2) | |
1079 | { | |
1080 | bool res; | |
1081 | ||
1082 | STRIP_NOPS (offset1); | |
1083 | STRIP_NOPS (offset2); | |
1084 | ||
1085 | if (offset1 == offset2) | |
1086 | return true; | |
1087 | ||
1088 | if (TREE_CODE (offset1) != TREE_CODE (offset2) | |
1089 | || (!BINARY_CLASS_P (offset1) && !UNARY_CLASS_P (offset1))) | |
1090 | return false; | |
1091 | ||
1092 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 0), | |
1093 | TREE_OPERAND (offset2, 0)); | |
1094 | ||
1095 | if (!res || !BINARY_CLASS_P (offset1)) | |
1096 | return res; | |
1097 | ||
1098 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 1), | |
1099 | TREE_OPERAND (offset2, 1)); | |
1100 | ||
1101 | return res; | |
1102 | } | |
1103 | ||
1104 | /* Check if DRA and DRB have equal offsets. */ | |
1105 | bool | |
1106 | dr_equal_offsets_p (struct data_reference *dra, | |
1107 | struct data_reference *drb) | |
1108 | { | |
1109 | tree offset1, offset2; | |
1110 | ||
1111 | offset1 = DR_OFFSET (dra); | |
1112 | offset2 = DR_OFFSET (drb); | |
1113 | ||
1114 | return dr_equal_offsets_p1 (offset1, offset2); | |
1115 | } | |
1116 | ||
d93817c4 ZD |
1117 | /* Returns true if FNA == FNB. */ |
1118 | ||
1119 | static bool | |
1120 | affine_function_equal_p (affine_fn fna, affine_fn fnb) | |
1121 | { | |
9771b263 | 1122 | unsigned i, n = fna.length (); |
86a07404 | 1123 | |
9771b263 | 1124 | if (n != fnb.length ()) |
f86289d5 | 1125 | return false; |
86df10e3 | 1126 | |
d93817c4 | 1127 | for (i = 0; i < n; i++) |
9771b263 | 1128 | if (!operand_equal_p (fna[i], fnb[i], 0)) |
d93817c4 ZD |
1129 | return false; |
1130 | ||
1131 | return true; | |
1132 | } | |
1133 | ||
1134 | /* If all the functions in CF are the same, returns one of them, | |
1135 | otherwise returns NULL. */ | |
1136 | ||
1137 | static affine_fn | |
1138 | common_affine_function (conflict_function *cf) | |
86df10e3 | 1139 | { |
d93817c4 ZD |
1140 | unsigned i; |
1141 | affine_fn comm; | |
1142 | ||
1143 | if (!CF_NONTRIVIAL_P (cf)) | |
c3284718 | 1144 | return affine_fn (); |
d93817c4 ZD |
1145 | |
1146 | comm = cf->fns[0]; | |
1147 | ||
1148 | for (i = 1; i < cf->n; i++) | |
1149 | if (!affine_function_equal_p (comm, cf->fns[i])) | |
c3284718 | 1150 | return affine_fn (); |
d93817c4 ZD |
1151 | |
1152 | return comm; | |
1153 | } | |
86df10e3 | 1154 | |
d93817c4 ZD |
1155 | /* Returns the base of the affine function FN. */ |
1156 | ||
1157 | static tree | |
1158 | affine_function_base (affine_fn fn) | |
1159 | { | |
9771b263 | 1160 | return fn[0]; |
d93817c4 ZD |
1161 | } |
1162 | ||
1163 | /* Returns true if FN is a constant. */ | |
1164 | ||
1165 | static bool | |
1166 | affine_function_constant_p (affine_fn fn) | |
1167 | { | |
1168 | unsigned i; | |
1169 | tree coef; | |
1170 | ||
9771b263 | 1171 | for (i = 1; fn.iterate (i, &coef); i++) |
d93817c4 | 1172 | if (!integer_zerop (coef)) |
e2157b49 SP |
1173 | return false; |
1174 | ||
86df10e3 SP |
1175 | return true; |
1176 | } | |
1177 | ||
1baf2906 SP |
1178 | /* Returns true if FN is the zero constant function. */ |
1179 | ||
1180 | static bool | |
1181 | affine_function_zero_p (affine_fn fn) | |
1182 | { | |
1183 | return (integer_zerop (affine_function_base (fn)) | |
1184 | && affine_function_constant_p (fn)); | |
1185 | } | |
1186 | ||
33b30201 SP |
1187 | /* Returns a signed integer type with the largest precision from TA |
1188 | and TB. */ | |
1189 | ||
1190 | static tree | |
1191 | signed_type_for_types (tree ta, tree tb) | |
1192 | { | |
1193 | if (TYPE_PRECISION (ta) > TYPE_PRECISION (tb)) | |
1194 | return signed_type_for (ta); | |
1195 | else | |
1196 | return signed_type_for (tb); | |
1197 | } | |
1198 | ||
d93817c4 ZD |
1199 | /* Applies operation OP on affine functions FNA and FNB, and returns the |
1200 | result. */ | |
1201 | ||
1202 | static affine_fn | |
1203 | affine_fn_op (enum tree_code op, affine_fn fna, affine_fn fnb) | |
1204 | { | |
1205 | unsigned i, n, m; | |
1206 | affine_fn ret; | |
1207 | tree coef; | |
1208 | ||
9771b263 | 1209 | if (fnb.length () > fna.length ()) |
d93817c4 | 1210 | { |
9771b263 DN |
1211 | n = fna.length (); |
1212 | m = fnb.length (); | |
d93817c4 ZD |
1213 | } |
1214 | else | |
1215 | { | |
9771b263 DN |
1216 | n = fnb.length (); |
1217 | m = fna.length (); | |
d93817c4 ZD |
1218 | } |
1219 | ||
9771b263 | 1220 | ret.create (m); |
d93817c4 | 1221 | for (i = 0; i < n; i++) |
33b30201 | 1222 | { |
9771b263 DN |
1223 | tree type = signed_type_for_types (TREE_TYPE (fna[i]), |
1224 | TREE_TYPE (fnb[i])); | |
1225 | ret.quick_push (fold_build2 (op, type, fna[i], fnb[i])); | |
33b30201 | 1226 | } |
d93817c4 | 1227 | |
9771b263 DN |
1228 | for (; fna.iterate (i, &coef); i++) |
1229 | ret.quick_push (fold_build2 (op, signed_type_for (TREE_TYPE (coef)), | |
d93817c4 | 1230 | coef, integer_zero_node)); |
9771b263 DN |
1231 | for (; fnb.iterate (i, &coef); i++) |
1232 | ret.quick_push (fold_build2 (op, signed_type_for (TREE_TYPE (coef)), | |
d93817c4 ZD |
1233 | integer_zero_node, coef)); |
1234 | ||
1235 | return ret; | |
1236 | } | |
1237 | ||
1238 | /* Returns the sum of affine functions FNA and FNB. */ | |
1239 | ||
1240 | static affine_fn | |
1241 | affine_fn_plus (affine_fn fna, affine_fn fnb) | |
1242 | { | |
1243 | return affine_fn_op (PLUS_EXPR, fna, fnb); | |
1244 | } | |
1245 | ||
1246 | /* Returns the difference of affine functions FNA and FNB. */ | |
1247 | ||
1248 | static affine_fn | |
1249 | affine_fn_minus (affine_fn fna, affine_fn fnb) | |
1250 | { | |
1251 | return affine_fn_op (MINUS_EXPR, fna, fnb); | |
1252 | } | |
1253 | ||
1254 | /* Frees affine function FN. */ | |
1255 | ||
1256 | static void | |
1257 | affine_fn_free (affine_fn fn) | |
1258 | { | |
9771b263 | 1259 | fn.release (); |
d93817c4 ZD |
1260 | } |
1261 | ||
86df10e3 SP |
1262 | /* Determine for each subscript in the data dependence relation DDR |
1263 | the distance. */ | |
56cf8686 | 1264 | |
0ff4040e | 1265 | static void |
86df10e3 | 1266 | compute_subscript_distance (struct data_dependence_relation *ddr) |
56cf8686 | 1267 | { |
d93817c4 ZD |
1268 | conflict_function *cf_a, *cf_b; |
1269 | affine_fn fn_a, fn_b, diff; | |
1270 | ||
56cf8686 SP |
1271 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
1272 | { | |
1273 | unsigned int i; | |
b8698a0f | 1274 | |
56cf8686 SP |
1275 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
1276 | { | |
56cf8686 | 1277 | struct subscript *subscript; |
b8698a0f | 1278 | |
56cf8686 | 1279 | subscript = DDR_SUBSCRIPT (ddr, i); |
d93817c4 ZD |
1280 | cf_a = SUB_CONFLICTS_IN_A (subscript); |
1281 | cf_b = SUB_CONFLICTS_IN_B (subscript); | |
86df10e3 | 1282 | |
d93817c4 ZD |
1283 | fn_a = common_affine_function (cf_a); |
1284 | fn_b = common_affine_function (cf_b); | |
9771b263 | 1285 | if (!fn_a.exists () || !fn_b.exists ()) |
86df10e3 | 1286 | { |
d93817c4 ZD |
1287 | SUB_DISTANCE (subscript) = chrec_dont_know; |
1288 | return; | |
86df10e3 | 1289 | } |
d93817c4 | 1290 | diff = affine_fn_minus (fn_a, fn_b); |
b8698a0f | 1291 | |
d93817c4 ZD |
1292 | if (affine_function_constant_p (diff)) |
1293 | SUB_DISTANCE (subscript) = affine_function_base (diff); | |
56cf8686 SP |
1294 | else |
1295 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
d93817c4 ZD |
1296 | |
1297 | affine_fn_free (diff); | |
56cf8686 SP |
1298 | } |
1299 | } | |
1300 | } | |
1301 | ||
d93817c4 ZD |
1302 | /* Returns the conflict function for "unknown". */ |
1303 | ||
1304 | static conflict_function * | |
1305 | conflict_fn_not_known (void) | |
1306 | { | |
1307 | conflict_function *fn = XCNEW (conflict_function); | |
1308 | fn->n = NOT_KNOWN; | |
1309 | ||
1310 | return fn; | |
1311 | } | |
1312 | ||
1313 | /* Returns the conflict function for "independent". */ | |
1314 | ||
1315 | static conflict_function * | |
1316 | conflict_fn_no_dependence (void) | |
1317 | { | |
1318 | conflict_function *fn = XCNEW (conflict_function); | |
1319 | fn->n = NO_DEPENDENCE; | |
1320 | ||
1321 | return fn; | |
1322 | } | |
1323 | ||
3cb960c7 ZD |
1324 | /* Returns true if the address of OBJ is invariant in LOOP. */ |
1325 | ||
1326 | static bool | |
ed7a4b4b | 1327 | object_address_invariant_in_loop_p (const struct loop *loop, const_tree obj) |
3cb960c7 ZD |
1328 | { |
1329 | while (handled_component_p (obj)) | |
1330 | { | |
1331 | if (TREE_CODE (obj) == ARRAY_REF) | |
1332 | { | |
1333 | /* Index of the ARRAY_REF was zeroed in analyze_indices, thus we only | |
1334 | need to check the stride and the lower bound of the reference. */ | |
1335 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1336 | loop->num) | |
1337 | || chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 3), | |
1338 | loop->num)) | |
1339 | return false; | |
1340 | } | |
1341 | else if (TREE_CODE (obj) == COMPONENT_REF) | |
1342 | { | |
1343 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1344 | loop->num)) | |
1345 | return false; | |
1346 | } | |
1347 | obj = TREE_OPERAND (obj, 0); | |
1348 | } | |
1349 | ||
70f34814 RG |
1350 | if (!INDIRECT_REF_P (obj) |
1351 | && TREE_CODE (obj) != MEM_REF) | |
3cb960c7 ZD |
1352 | return true; |
1353 | ||
1354 | return !chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 0), | |
1355 | loop->num); | |
1356 | } | |
1357 | ||
3cb960c7 | 1358 | /* Returns false if we can prove that data references A and B do not alias, |
02f5d6c5 RG |
1359 | true otherwise. If LOOP_NEST is false no cross-iteration aliases are |
1360 | considered. */ | |
3cb960c7 | 1361 | |
f8bf9252 | 1362 | bool |
02f5d6c5 RG |
1363 | dr_may_alias_p (const struct data_reference *a, const struct data_reference *b, |
1364 | bool loop_nest) | |
3cb960c7 | 1365 | { |
7d36e538 RG |
1366 | tree addr_a = DR_BASE_OBJECT (a); |
1367 | tree addr_b = DR_BASE_OBJECT (b); | |
3cb960c7 | 1368 | |
02f5d6c5 RG |
1369 | /* If we are not processing a loop nest but scalar code we |
1370 | do not need to care about possible cross-iteration dependences | |
1371 | and thus can process the full original reference. Do so, | |
1372 | similar to how loop invariant motion applies extra offset-based | |
1373 | disambiguation. */ | |
1374 | if (!loop_nest) | |
1375 | { | |
1376 | aff_tree off1, off2; | |
1377 | double_int size1, size2; | |
1378 | get_inner_reference_aff (DR_REF (a), &off1, &size1); | |
1379 | get_inner_reference_aff (DR_REF (b), &off2, &size2); | |
1380 | aff_combination_scale (&off1, double_int_minus_one); | |
1381 | aff_combination_add (&off2, &off1); | |
1382 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) | |
1383 | return false; | |
1384 | } | |
1385 | ||
c4ddde1b RG |
1386 | /* If we had an evolution in a MEM_REF BASE_OBJECT we do not know |
1387 | the size of the base-object. So we cannot do any offset/overlap | |
1388 | based analysis but have to rely on points-to information only. */ | |
1389 | if (TREE_CODE (addr_a) == MEM_REF | |
1390 | && DR_UNCONSTRAINED_BASE (a)) | |
1391 | { | |
1392 | if (TREE_CODE (addr_b) == MEM_REF | |
1393 | && DR_UNCONSTRAINED_BASE (b)) | |
1394 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), | |
1395 | TREE_OPERAND (addr_b, 0)); | |
1396 | else | |
1397 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), | |
1398 | build_fold_addr_expr (addr_b)); | |
1399 | } | |
1400 | else if (TREE_CODE (addr_b) == MEM_REF | |
1401 | && DR_UNCONSTRAINED_BASE (b)) | |
1402 | return ptr_derefs_may_alias_p (build_fold_addr_expr (addr_a), | |
1403 | TREE_OPERAND (addr_b, 0)); | |
1404 | ||
1405 | /* Otherwise DR_BASE_OBJECT is an access that covers the whole object | |
1406 | that is being subsetted in the loop nest. */ | |
b0af49c4 | 1407 | if (DR_IS_WRITE (a) && DR_IS_WRITE (b)) |
7d36e538 | 1408 | return refs_output_dependent_p (addr_a, addr_b); |
b0af49c4 | 1409 | else if (DR_IS_READ (a) && DR_IS_WRITE (b)) |
7d36e538 RG |
1410 | return refs_anti_dependent_p (addr_a, addr_b); |
1411 | return refs_may_alias_p (addr_a, addr_b); | |
3cb960c7 ZD |
1412 | } |
1413 | ||
0ff4040e SP |
1414 | /* Initialize a data dependence relation between data accesses A and |
1415 | B. NB_LOOPS is the number of loops surrounding the references: the | |
1416 | size of the classic distance/direction vectors. */ | |
56cf8686 | 1417 | |
aec7ae7d | 1418 | struct data_dependence_relation * |
b8698a0f | 1419 | initialize_data_dependence_relation (struct data_reference *a, |
0ff4040e | 1420 | struct data_reference *b, |
9771b263 | 1421 | vec<loop_p> loop_nest) |
56cf8686 SP |
1422 | { |
1423 | struct data_dependence_relation *res; | |
0ff4040e | 1424 | unsigned int i; |
b8698a0f | 1425 | |
5ed6ace5 | 1426 | res = XNEW (struct data_dependence_relation); |
56cf8686 SP |
1427 | DDR_A (res) = a; |
1428 | DDR_B (res) = b; | |
9771b263 | 1429 | DDR_LOOP_NEST (res).create (0); |
71d5b5e1 | 1430 | DDR_REVERSED_P (res) = false; |
9771b263 DN |
1431 | DDR_SUBSCRIPTS (res).create (0); |
1432 | DDR_DIR_VECTS (res).create (0); | |
1433 | DDR_DIST_VECTS (res).create (0); | |
56cf8686 | 1434 | |
86a07404 IR |
1435 | if (a == NULL || b == NULL) |
1436 | { | |
b8698a0f | 1437 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 | 1438 | return res; |
b8698a0f | 1439 | } |
86a07404 | 1440 | |
3cb960c7 | 1441 | /* If the data references do not alias, then they are independent. */ |
9771b263 | 1442 | if (!dr_may_alias_p (a, b, loop_nest.exists ())) |
86a07404 | 1443 | { |
b8698a0f | 1444 | DDR_ARE_DEPENDENT (res) = chrec_known; |
86a07404 IR |
1445 | return res; |
1446 | } | |
56cf8686 | 1447 | |
fea99a37 | 1448 | /* The case where the references are exactly the same. */ |
b3924be9 SP |
1449 | if (operand_equal_p (DR_REF (a), DR_REF (b), 0)) |
1450 | { | |
9771b263 DN |
1451 | if (loop_nest.exists () |
1452 | && !object_address_invariant_in_loop_p (loop_nest[0], | |
1a4571cb RL |
1453 | DR_BASE_OBJECT (a))) |
1454 | { | |
1455 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1456 | return res; | |
1457 | } | |
b3924be9 SP |
1458 | DDR_AFFINE_P (res) = true; |
1459 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
9771b263 | 1460 | DDR_SUBSCRIPTS (res).create (DR_NUM_DIMENSIONS (a)); |
b3924be9 SP |
1461 | DDR_LOOP_NEST (res) = loop_nest; |
1462 | DDR_INNER_LOOP (res) = 0; | |
1463 | DDR_SELF_REFERENCE (res) = true; | |
1a4571cb RL |
1464 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1465 | { | |
1466 | struct subscript *subscript; | |
1467 | ||
1468 | subscript = XNEW (struct subscript); | |
1469 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); | |
1470 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
1471 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; | |
1472 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
9771b263 | 1473 | DDR_SUBSCRIPTS (res).safe_push (subscript); |
1a4571cb | 1474 | } |
b3924be9 SP |
1475 | return res; |
1476 | } | |
1477 | ||
3cb960c7 ZD |
1478 | /* If the references do not access the same object, we do not know |
1479 | whether they alias or not. */ | |
1480 | if (!operand_equal_p (DR_BASE_OBJECT (a), DR_BASE_OBJECT (b), 0)) | |
56cf8686 | 1481 | { |
b8698a0f | 1482 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1483 | return res; |
1484 | } | |
0ff4040e | 1485 | |
3cb960c7 | 1486 | /* If the base of the object is not invariant in the loop nest, we cannot |
0d52bcc1 | 1487 | analyze it. TODO -- in fact, it would suffice to record that there may |
c80b4100 | 1488 | be arbitrary dependences in the loops where the base object varies. */ |
9771b263 DN |
1489 | if (loop_nest.exists () |
1490 | && !object_address_invariant_in_loop_p (loop_nest[0], | |
a70d6342 | 1491 | DR_BASE_OBJECT (a))) |
86a07404 | 1492 | { |
b8698a0f | 1493 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1494 | return res; |
1495 | } | |
3cb960c7 | 1496 | |
19368333 RG |
1497 | /* If the number of dimensions of the access to not agree we can have |
1498 | a pointer access to a component of the array element type and an | |
1499 | array access while the base-objects are still the same. Punt. */ | |
1500 | if (DR_NUM_DIMENSIONS (a) != DR_NUM_DIMENSIONS (b)) | |
1501 | { | |
1502 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1503 | return res; | |
1504 | } | |
3cb960c7 | 1505 | |
86a07404 IR |
1506 | DDR_AFFINE_P (res) = true; |
1507 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
9771b263 | 1508 | DDR_SUBSCRIPTS (res).create (DR_NUM_DIMENSIONS (a)); |
ba42e045 | 1509 | DDR_LOOP_NEST (res) = loop_nest; |
3d8864c0 | 1510 | DDR_INNER_LOOP (res) = 0; |
b3924be9 | 1511 | DDR_SELF_REFERENCE (res) = false; |
304afda6 | 1512 | |
86a07404 IR |
1513 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1514 | { | |
1515 | struct subscript *subscript; | |
b8698a0f | 1516 | |
5ed6ace5 | 1517 | subscript = XNEW (struct subscript); |
d93817c4 ZD |
1518 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); |
1519 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
86a07404 IR |
1520 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
1521 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
9771b263 | 1522 | DDR_SUBSCRIPTS (res).safe_push (subscript); |
56cf8686 | 1523 | } |
ebf78a47 | 1524 | |
56cf8686 SP |
1525 | return res; |
1526 | } | |
1527 | ||
d93817c4 ZD |
1528 | /* Frees memory used by the conflict function F. */ |
1529 | ||
1530 | static void | |
1531 | free_conflict_function (conflict_function *f) | |
1532 | { | |
1533 | unsigned i; | |
1534 | ||
1535 | if (CF_NONTRIVIAL_P (f)) | |
1536 | { | |
1537 | for (i = 0; i < f->n; i++) | |
1538 | affine_fn_free (f->fns[i]); | |
1539 | } | |
1540 | free (f); | |
1541 | } | |
1542 | ||
1543 | /* Frees memory used by SUBSCRIPTS. */ | |
1544 | ||
1545 | static void | |
9771b263 | 1546 | free_subscripts (vec<subscript_p> subscripts) |
d93817c4 ZD |
1547 | { |
1548 | unsigned i; | |
1549 | subscript_p s; | |
1550 | ||
9771b263 | 1551 | FOR_EACH_VEC_ELT (subscripts, i, s) |
d93817c4 ZD |
1552 | { |
1553 | free_conflict_function (s->conflicting_iterations_in_a); | |
1554 | free_conflict_function (s->conflicting_iterations_in_b); | |
a0044be5 | 1555 | free (s); |
d93817c4 | 1556 | } |
9771b263 | 1557 | subscripts.release (); |
d93817c4 ZD |
1558 | } |
1559 | ||
56cf8686 SP |
1560 | /* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap |
1561 | description. */ | |
1562 | ||
1563 | static inline void | |
b8698a0f | 1564 | finalize_ddr_dependent (struct data_dependence_relation *ddr, |
56cf8686 SP |
1565 | tree chrec) |
1566 | { | |
b8698a0f | 1567 | DDR_ARE_DEPENDENT (ddr) = chrec; |
d93817c4 | 1568 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
9771b263 | 1569 | DDR_SUBSCRIPTS (ddr).create (0); |
56cf8686 SP |
1570 | } |
1571 | ||
86df10e3 SP |
1572 | /* The dependence relation DDR cannot be represented by a distance |
1573 | vector. */ | |
1574 | ||
1575 | static inline void | |
1576 | non_affine_dependence_relation (struct data_dependence_relation *ddr) | |
1577 | { | |
1578 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1579 | fprintf (dump_file, "(Dependence relation cannot be represented by distance vector.) \n"); | |
1580 | ||
1581 | DDR_AFFINE_P (ddr) = false; | |
1582 | } | |
1583 | ||
56cf8686 SP |
1584 | \f |
1585 | ||
1586 | /* This section contains the classic Banerjee tests. */ | |
1587 | ||
1588 | /* Returns true iff CHREC_A and CHREC_B are not dependent on any index | |
1589 | variables, i.e., if the ZIV (Zero Index Variable) test is true. */ | |
1590 | ||
1591 | static inline bool | |
ed7a4b4b | 1592 | ziv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1593 | { |
1594 | return (evolution_function_is_constant_p (chrec_a) | |
1595 | && evolution_function_is_constant_p (chrec_b)); | |
1596 | } | |
1597 | ||
1598 | /* Returns true iff CHREC_A and CHREC_B are dependent on an index | |
1599 | variable, i.e., if the SIV (Single Index Variable) test is true. */ | |
1600 | ||
1601 | static bool | |
ed7a4b4b | 1602 | siv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1603 | { |
1604 | if ((evolution_function_is_constant_p (chrec_a) | |
1605 | && evolution_function_is_univariate_p (chrec_b)) | |
1606 | || (evolution_function_is_constant_p (chrec_b) | |
1607 | && evolution_function_is_univariate_p (chrec_a))) | |
1608 | return true; | |
b8698a0f | 1609 | |
56cf8686 SP |
1610 | if (evolution_function_is_univariate_p (chrec_a) |
1611 | && evolution_function_is_univariate_p (chrec_b)) | |
1612 | { | |
1613 | switch (TREE_CODE (chrec_a)) | |
1614 | { | |
1615 | case POLYNOMIAL_CHREC: | |
1616 | switch (TREE_CODE (chrec_b)) | |
1617 | { | |
1618 | case POLYNOMIAL_CHREC: | |
1619 | if (CHREC_VARIABLE (chrec_a) != CHREC_VARIABLE (chrec_b)) | |
1620 | return false; | |
b8698a0f | 1621 | |
56cf8686 SP |
1622 | default: |
1623 | return true; | |
1624 | } | |
b8698a0f | 1625 | |
56cf8686 SP |
1626 | default: |
1627 | return true; | |
1628 | } | |
1629 | } | |
b8698a0f | 1630 | |
56cf8686 SP |
1631 | return false; |
1632 | } | |
1633 | ||
d93817c4 ZD |
1634 | /* Creates a conflict function with N dimensions. The affine functions |
1635 | in each dimension follow. */ | |
1636 | ||
1637 | static conflict_function * | |
1638 | conflict_fn (unsigned n, ...) | |
1639 | { | |
1640 | unsigned i; | |
1641 | conflict_function *ret = XCNEW (conflict_function); | |
1642 | va_list ap; | |
1643 | ||
b39c6706 | 1644 | gcc_assert (0 < n && n <= MAX_DIM); |
c3284718 | 1645 | va_start (ap, n); |
b8698a0f | 1646 | |
d93817c4 ZD |
1647 | ret->n = n; |
1648 | for (i = 0; i < n; i++) | |
1649 | ret->fns[i] = va_arg (ap, affine_fn); | |
c3284718 | 1650 | va_end (ap); |
d93817c4 ZD |
1651 | |
1652 | return ret; | |
1653 | } | |
1654 | ||
1655 | /* Returns constant affine function with value CST. */ | |
1656 | ||
1657 | static affine_fn | |
1658 | affine_fn_cst (tree cst) | |
1659 | { | |
9771b263 DN |
1660 | affine_fn fn; |
1661 | fn.create (1); | |
1662 | fn.quick_push (cst); | |
d93817c4 ZD |
1663 | return fn; |
1664 | } | |
1665 | ||
1666 | /* Returns affine function with single variable, CST + COEF * x_DIM. */ | |
1667 | ||
1668 | static affine_fn | |
1669 | affine_fn_univar (tree cst, unsigned dim, tree coef) | |
1670 | { | |
9771b263 DN |
1671 | affine_fn fn; |
1672 | fn.create (dim + 1); | |
d93817c4 ZD |
1673 | unsigned i; |
1674 | ||
1675 | gcc_assert (dim > 0); | |
9771b263 | 1676 | fn.quick_push (cst); |
d93817c4 | 1677 | for (i = 1; i < dim; i++) |
9771b263 DN |
1678 | fn.quick_push (integer_zero_node); |
1679 | fn.quick_push (coef); | |
d93817c4 ZD |
1680 | return fn; |
1681 | } | |
1682 | ||
56cf8686 SP |
1683 | /* Analyze a ZIV (Zero Index Variable) subscript. *OVERLAPS_A and |
1684 | *OVERLAPS_B are initialized to the functions that describe the | |
1685 | relation between the elements accessed twice by CHREC_A and | |
1686 | CHREC_B. For k >= 0, the following property is verified: | |
1687 | ||
1688 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1689 | ||
b8698a0f L |
1690 | static void |
1691 | analyze_ziv_subscript (tree chrec_a, | |
1692 | tree chrec_b, | |
d93817c4 | 1693 | conflict_function **overlaps_a, |
b8698a0f | 1694 | conflict_function **overlaps_b, |
86df10e3 | 1695 | tree *last_conflicts) |
56cf8686 | 1696 | { |
33b30201 | 1697 | tree type, difference; |
0ff4040e | 1698 | dependence_stats.num_ziv++; |
b8698a0f | 1699 | |
56cf8686 SP |
1700 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1701 | fprintf (dump_file, "(analyze_ziv_subscript \n"); | |
33b30201 SP |
1702 | |
1703 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); | |
726a989a RB |
1704 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1705 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1706 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
b8698a0f | 1707 | |
56cf8686 SP |
1708 | switch (TREE_CODE (difference)) |
1709 | { | |
1710 | case INTEGER_CST: | |
1711 | if (integer_zerop (difference)) | |
1712 | { | |
1713 | /* The difference is equal to zero: the accessed index | |
1714 | overlaps for each iteration in the loop. */ | |
d93817c4 ZD |
1715 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
1716 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 | 1717 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1718 | dependence_stats.num_ziv_dependent++; |
56cf8686 SP |
1719 | } |
1720 | else | |
1721 | { | |
1722 | /* The accesses do not overlap. */ | |
d93817c4 ZD |
1723 | *overlaps_a = conflict_fn_no_dependence (); |
1724 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1725 | *last_conflicts = integer_zero_node; |
0ff4040e | 1726 | dependence_stats.num_ziv_independent++; |
56cf8686 SP |
1727 | } |
1728 | break; | |
b8698a0f | 1729 | |
56cf8686 | 1730 | default: |
b8698a0f | 1731 | /* We're not sure whether the indexes overlap. For the moment, |
56cf8686 | 1732 | conservatively answer "don't know". */ |
0ff4040e SP |
1733 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1734 | fprintf (dump_file, "ziv test failed: difference is non-integer.\n"); | |
1735 | ||
d93817c4 ZD |
1736 | *overlaps_a = conflict_fn_not_known (); |
1737 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1738 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1739 | dependence_stats.num_ziv_unimplemented++; |
56cf8686 SP |
1740 | break; |
1741 | } | |
b8698a0f | 1742 | |
56cf8686 SP |
1743 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1744 | fprintf (dump_file, ")\n"); | |
1745 | } | |
1746 | ||
b4a9343c | 1747 | /* Similar to max_stmt_executions_int, but returns the bound as a tree, |
4839cb59 | 1748 | and only if it fits to the int type. If this is not the case, or the |
b4a9343c | 1749 | bound on the number of iterations of LOOP could not be derived, returns |
4839cb59 ZD |
1750 | chrec_dont_know. */ |
1751 | ||
1752 | static tree | |
b4a9343c | 1753 | max_stmt_executions_tree (struct loop *loop) |
4839cb59 ZD |
1754 | { |
1755 | double_int nit; | |
4839cb59 | 1756 | |
652c4c71 | 1757 | if (!max_stmt_executions (loop, &nit)) |
4839cb59 ZD |
1758 | return chrec_dont_know; |
1759 | ||
5f72e02d | 1760 | if (!double_int_fits_to_tree_p (unsigned_type_node, nit)) |
4839cb59 ZD |
1761 | return chrec_dont_know; |
1762 | ||
5f72e02d | 1763 | return double_int_to_tree (unsigned_type_node, nit); |
4839cb59 ZD |
1764 | } |
1765 | ||
5f1fab58 RG |
1766 | /* Determine whether the CHREC is always positive/negative. If the expression |
1767 | cannot be statically analyzed, return false, otherwise set the answer into | |
1768 | VALUE. */ | |
1769 | ||
1770 | static bool | |
1771 | chrec_is_positive (tree chrec, bool *value) | |
1772 | { | |
1773 | bool value0, value1, value2; | |
1774 | tree end_value, nb_iter; | |
1775 | ||
1776 | switch (TREE_CODE (chrec)) | |
1777 | { | |
1778 | case POLYNOMIAL_CHREC: | |
1779 | if (!chrec_is_positive (CHREC_LEFT (chrec), &value0) | |
1780 | || !chrec_is_positive (CHREC_RIGHT (chrec), &value1)) | |
1781 | return false; | |
1782 | ||
1783 | /* FIXME -- overflows. */ | |
1784 | if (value0 == value1) | |
1785 | { | |
1786 | *value = value0; | |
1787 | return true; | |
1788 | } | |
1789 | ||
1790 | /* Otherwise the chrec is under the form: "{-197, +, 2}_1", | |
1791 | and the proof consists in showing that the sign never | |
1792 | changes during the execution of the loop, from 0 to | |
1793 | loop->nb_iterations. */ | |
1794 | if (!evolution_function_is_affine_p (chrec)) | |
1795 | return false; | |
1796 | ||
1797 | nb_iter = number_of_latch_executions (get_chrec_loop (chrec)); | |
1798 | if (chrec_contains_undetermined (nb_iter)) | |
1799 | return false; | |
1800 | ||
1801 | #if 0 | |
1802 | /* TODO -- If the test is after the exit, we may decrease the number of | |
1803 | iterations by one. */ | |
1804 | if (after_exit) | |
1805 | nb_iter = chrec_fold_minus (type, nb_iter, build_int_cst (type, 1)); | |
1806 | #endif | |
1807 | ||
1808 | end_value = chrec_apply (CHREC_VARIABLE (chrec), chrec, nb_iter); | |
1809 | ||
1810 | if (!chrec_is_positive (end_value, &value2)) | |
1811 | return false; | |
1812 | ||
1813 | *value = value0; | |
1814 | return value0 == value1; | |
1815 | ||
1816 | case INTEGER_CST: | |
1817 | switch (tree_int_cst_sgn (chrec)) | |
1818 | { | |
1819 | case -1: | |
1820 | *value = false; | |
1821 | break; | |
1822 | case 1: | |
1823 | *value = true; | |
1824 | break; | |
1825 | default: | |
1826 | return false; | |
1827 | } | |
1828 | return true; | |
1829 | ||
1830 | default: | |
1831 | return false; | |
1832 | } | |
1833 | } | |
1834 | ||
1835 | ||
56cf8686 SP |
1836 | /* Analyze a SIV (Single Index Variable) subscript where CHREC_A is a |
1837 | constant, and CHREC_B is an affine function. *OVERLAPS_A and | |
1838 | *OVERLAPS_B are initialized to the functions that describe the | |
1839 | relation between the elements accessed twice by CHREC_A and | |
1840 | CHREC_B. For k >= 0, the following property is verified: | |
1841 | ||
1842 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1843 | ||
1844 | static void | |
b8698a0f | 1845 | analyze_siv_subscript_cst_affine (tree chrec_a, |
56cf8686 | 1846 | tree chrec_b, |
b8698a0f L |
1847 | conflict_function **overlaps_a, |
1848 | conflict_function **overlaps_b, | |
86df10e3 | 1849 | tree *last_conflicts) |
56cf8686 SP |
1850 | { |
1851 | bool value0, value1, value2; | |
33b30201 | 1852 | tree type, difference, tmp; |
e2157b49 | 1853 | |
33b30201 | 1854 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
1855 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1856 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1857 | difference = chrec_fold_minus (type, initial_condition (chrec_b), chrec_a); |
b8698a0f | 1858 | |
5f1fab58 RG |
1859 | /* Special case overlap in the first iteration. */ |
1860 | if (integer_zerop (difference)) | |
1861 | { | |
1862 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
1863 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
1864 | *last_conflicts = integer_one_node; | |
1865 | return; | |
1866 | } | |
1867 | ||
56cf8686 SP |
1868 | if (!chrec_is_positive (initial_condition (difference), &value0)) |
1869 | { | |
0ff4040e | 1870 | if (dump_file && (dump_flags & TDF_DETAILS)) |
b8698a0f | 1871 | fprintf (dump_file, "siv test failed: chrec is not positive.\n"); |
0ff4040e SP |
1872 | |
1873 | dependence_stats.num_siv_unimplemented++; | |
d93817c4 ZD |
1874 | *overlaps_a = conflict_fn_not_known (); |
1875 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1876 | *last_conflicts = chrec_dont_know; |
56cf8686 SP |
1877 | return; |
1878 | } | |
1879 | else | |
1880 | { | |
1881 | if (value0 == false) | |
1882 | { | |
1883 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value1)) | |
1884 | { | |
0ff4040e SP |
1885 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1886 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1887 | ||
d93817c4 | 1888 | *overlaps_a = conflict_fn_not_known (); |
b8698a0f | 1889 | *overlaps_b = conflict_fn_not_known (); |
86df10e3 | 1890 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1891 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1892 | return; |
1893 | } | |
1894 | else | |
1895 | { | |
1896 | if (value1 == true) | |
1897 | { | |
b8698a0f | 1898 | /* Example: |
56cf8686 SP |
1899 | chrec_a = 12 |
1900 | chrec_b = {10, +, 1} | |
1901 | */ | |
b8698a0f | 1902 | |
f457cf40 | 1903 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1904 | { |
4839cb59 ZD |
1905 | HOST_WIDE_INT numiter; |
1906 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1907 | |
d93817c4 | 1908 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 SP |
1909 | tmp = fold_build2 (EXACT_DIV_EXPR, type, |
1910 | fold_build1 (ABS_EXPR, type, difference), | |
d93817c4 ZD |
1911 | CHREC_RIGHT (chrec_b)); |
1912 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1913 | *last_conflicts = integer_one_node; |
b8698a0f | 1914 | |
416f403e DB |
1915 | |
1916 | /* Perform weak-zero siv test to see if overlap is | |
1917 | outside the loop bounds. */ | |
652c4c71 | 1918 | numiter = max_stmt_executions_int (loop); |
416f403e | 1919 | |
4839cb59 ZD |
1920 | if (numiter >= 0 |
1921 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 1922 | { |
d93817c4 ZD |
1923 | free_conflict_function (*overlaps_a); |
1924 | free_conflict_function (*overlaps_b); | |
1925 | *overlaps_a = conflict_fn_no_dependence (); | |
1926 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 1927 | *last_conflicts = integer_zero_node; |
0ff4040e | 1928 | dependence_stats.num_siv_independent++; |
416f403e | 1929 | return; |
b8698a0f | 1930 | } |
0ff4040e | 1931 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
1932 | return; |
1933 | } | |
b8698a0f | 1934 | |
f457cf40 | 1935 | /* When the step does not divide the difference, there are |
56cf8686 SP |
1936 | no overlaps. */ |
1937 | else | |
1938 | { | |
d93817c4 | 1939 | *overlaps_a = conflict_fn_no_dependence (); |
b8698a0f | 1940 | *overlaps_b = conflict_fn_no_dependence (); |
86df10e3 | 1941 | *last_conflicts = integer_zero_node; |
0ff4040e | 1942 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1943 | return; |
1944 | } | |
1945 | } | |
b8698a0f | 1946 | |
56cf8686 SP |
1947 | else |
1948 | { | |
b8698a0f | 1949 | /* Example: |
56cf8686 SP |
1950 | chrec_a = 12 |
1951 | chrec_b = {10, +, -1} | |
b8698a0f | 1952 | |
56cf8686 | 1953 | In this case, chrec_a will not overlap with chrec_b. */ |
d93817c4 ZD |
1954 | *overlaps_a = conflict_fn_no_dependence (); |
1955 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1956 | *last_conflicts = integer_zero_node; |
0ff4040e | 1957 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1958 | return; |
1959 | } | |
1960 | } | |
1961 | } | |
b8698a0f | 1962 | else |
56cf8686 SP |
1963 | { |
1964 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value2)) | |
1965 | { | |
0ff4040e SP |
1966 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1967 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1968 | ||
d93817c4 | 1969 | *overlaps_a = conflict_fn_not_known (); |
b8698a0f | 1970 | *overlaps_b = conflict_fn_not_known (); |
86df10e3 | 1971 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1972 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1973 | return; |
1974 | } | |
1975 | else | |
1976 | { | |
1977 | if (value2 == false) | |
1978 | { | |
b8698a0f | 1979 | /* Example: |
56cf8686 SP |
1980 | chrec_a = 3 |
1981 | chrec_b = {10, +, -1} | |
1982 | */ | |
f457cf40 | 1983 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1984 | { |
4839cb59 ZD |
1985 | HOST_WIDE_INT numiter; |
1986 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1987 | |
d93817c4 | 1988 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 | 1989 | tmp = fold_build2 (EXACT_DIV_EXPR, type, difference, |
d93817c4 ZD |
1990 | CHREC_RIGHT (chrec_b)); |
1991 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1992 | *last_conflicts = integer_one_node; |
416f403e DB |
1993 | |
1994 | /* Perform weak-zero siv test to see if overlap is | |
1995 | outside the loop bounds. */ | |
652c4c71 | 1996 | numiter = max_stmt_executions_int (loop); |
416f403e | 1997 | |
4839cb59 ZD |
1998 | if (numiter >= 0 |
1999 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 2000 | { |
d93817c4 ZD |
2001 | free_conflict_function (*overlaps_a); |
2002 | free_conflict_function (*overlaps_b); | |
2003 | *overlaps_a = conflict_fn_no_dependence (); | |
2004 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 2005 | *last_conflicts = integer_zero_node; |
0ff4040e | 2006 | dependence_stats.num_siv_independent++; |
416f403e | 2007 | return; |
b8698a0f | 2008 | } |
0ff4040e | 2009 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
2010 | return; |
2011 | } | |
b8698a0f | 2012 | |
4286d8ce | 2013 | /* When the step does not divide the difference, there |
56cf8686 SP |
2014 | are no overlaps. */ |
2015 | else | |
2016 | { | |
d93817c4 | 2017 | *overlaps_a = conflict_fn_no_dependence (); |
b8698a0f | 2018 | *overlaps_b = conflict_fn_no_dependence (); |
86df10e3 | 2019 | *last_conflicts = integer_zero_node; |
0ff4040e | 2020 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
2021 | return; |
2022 | } | |
2023 | } | |
2024 | else | |
2025 | { | |
b8698a0f L |
2026 | /* Example: |
2027 | chrec_a = 3 | |
56cf8686 | 2028 | chrec_b = {4, +, 1} |
b8698a0f | 2029 | |
56cf8686 | 2030 | In this case, chrec_a will not overlap with chrec_b. */ |
d93817c4 ZD |
2031 | *overlaps_a = conflict_fn_no_dependence (); |
2032 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2033 | *last_conflicts = integer_zero_node; |
0ff4040e | 2034 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
2035 | return; |
2036 | } | |
2037 | } | |
2038 | } | |
2039 | } | |
2040 | } | |
2041 | ||
50300b4c | 2042 | /* Helper recursive function for initializing the matrix A. Returns |
86df10e3 | 2043 | the initial value of CHREC. */ |
56cf8686 | 2044 | |
5b78fc3e | 2045 | static tree |
86df10e3 SP |
2046 | initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) |
2047 | { | |
2048 | gcc_assert (chrec); | |
2049 | ||
5b78fc3e JS |
2050 | switch (TREE_CODE (chrec)) |
2051 | { | |
2052 | case POLYNOMIAL_CHREC: | |
2053 | gcc_assert (TREE_CODE (CHREC_RIGHT (chrec)) == INTEGER_CST); | |
2054 | ||
2055 | A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); | |
2056 | return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); | |
2057 | ||
2058 | case PLUS_EXPR: | |
2059 | case MULT_EXPR: | |
2060 | case MINUS_EXPR: | |
2061 | { | |
2062 | tree op0 = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
2063 | tree op1 = initialize_matrix_A (A, TREE_OPERAND (chrec, 1), index, mult); | |
2064 | ||
2065 | return chrec_fold_op (TREE_CODE (chrec), chrec_type (chrec), op0, op1); | |
2066 | } | |
2067 | ||
2068 | case NOP_EXPR: | |
2069 | { | |
2070 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
726a989a | 2071 | return chrec_convert (chrec_type (chrec), op, NULL); |
5b78fc3e JS |
2072 | } |
2073 | ||
418df9d7 JJ |
2074 | case BIT_NOT_EXPR: |
2075 | { | |
2076 | /* Handle ~X as -1 - X. */ | |
2077 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
2078 | return chrec_fold_op (MINUS_EXPR, chrec_type (chrec), | |
2079 | build_int_cst (TREE_TYPE (chrec), -1), op); | |
2080 | } | |
2081 | ||
5b78fc3e JS |
2082 | case INTEGER_CST: |
2083 | return chrec; | |
a1a5996d | 2084 | |
5b78fc3e JS |
2085 | default: |
2086 | gcc_unreachable (); | |
2087 | return NULL_TREE; | |
2088 | } | |
86df10e3 SP |
2089 | } |
2090 | ||
2091 | #define FLOOR_DIV(x,y) ((x) / (y)) | |
2092 | ||
b8698a0f | 2093 | /* Solves the special case of the Diophantine equation: |
86df10e3 SP |
2094 | | {0, +, STEP_A}_x (OVERLAPS_A) = {0, +, STEP_B}_y (OVERLAPS_B) |
2095 | ||
2096 | Computes the descriptions OVERLAPS_A and OVERLAPS_B. NITER is the | |
2097 | number of iterations that loops X and Y run. The overlaps will be | |
2098 | constructed as evolutions in dimension DIM. */ | |
56cf8686 SP |
2099 | |
2100 | static void | |
b8698a0f | 2101 | compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b, |
d93817c4 | 2102 | affine_fn *overlaps_a, |
b8698a0f | 2103 | affine_fn *overlaps_b, |
86df10e3 SP |
2104 | tree *last_conflicts, int dim) |
2105 | { | |
2106 | if (((step_a > 0 && step_b > 0) | |
2107 | || (step_a < 0 && step_b < 0))) | |
2108 | { | |
2109 | int step_overlaps_a, step_overlaps_b; | |
2110 | int gcd_steps_a_b, last_conflict, tau2; | |
2111 | ||
2112 | gcd_steps_a_b = gcd (step_a, step_b); | |
2113 | step_overlaps_a = step_b / gcd_steps_a_b; | |
2114 | step_overlaps_b = step_a / gcd_steps_a_b; | |
2115 | ||
2c26cbfd SP |
2116 | if (niter > 0) |
2117 | { | |
2118 | tau2 = FLOOR_DIV (niter, step_overlaps_a); | |
2119 | tau2 = MIN (tau2, FLOOR_DIV (niter, step_overlaps_b)); | |
2120 | last_conflict = tau2; | |
2121 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); | |
2122 | } | |
2123 | else | |
2124 | *last_conflicts = chrec_dont_know; | |
86df10e3 | 2125 | |
b8698a0f | 2126 | *overlaps_a = affine_fn_univar (integer_zero_node, dim, |
d93817c4 ZD |
2127 | build_int_cst (NULL_TREE, |
2128 | step_overlaps_a)); | |
b8698a0f L |
2129 | *overlaps_b = affine_fn_univar (integer_zero_node, dim, |
2130 | build_int_cst (NULL_TREE, | |
d93817c4 | 2131 | step_overlaps_b)); |
86df10e3 SP |
2132 | } |
2133 | ||
2134 | else | |
2135 | { | |
d93817c4 ZD |
2136 | *overlaps_a = affine_fn_cst (integer_zero_node); |
2137 | *overlaps_b = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
2138 | *last_conflicts = integer_zero_node; |
2139 | } | |
2140 | } | |
2141 | ||
86df10e3 SP |
2142 | /* Solves the special case of a Diophantine equation where CHREC_A is |
2143 | an affine bivariate function, and CHREC_B is an affine univariate | |
b8698a0f | 2144 | function. For example, |
86df10e3 SP |
2145 | |
2146 | | {{0, +, 1}_x, +, 1335}_y = {0, +, 1336}_z | |
b8698a0f L |
2147 | |
2148 | has the following overlapping functions: | |
86df10e3 SP |
2149 | |
2150 | | x (t, u, v) = {{0, +, 1336}_t, +, 1}_v | |
2151 | | y (t, u, v) = {{0, +, 1336}_u, +, 1}_v | |
2152 | | z (t, u, v) = {{{0, +, 1}_t, +, 1335}_u, +, 1}_v | |
2153 | ||
35fd3193 | 2154 | FORNOW: This is a specialized implementation for a case occurring in |
86df10e3 SP |
2155 | a common benchmark. Implement the general algorithm. */ |
2156 | ||
2157 | static void | |
b8698a0f | 2158 | compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b, |
d93817c4 | 2159 | conflict_function **overlaps_a, |
b8698a0f | 2160 | conflict_function **overlaps_b, |
86df10e3 | 2161 | tree *last_conflicts) |
56cf8686 | 2162 | { |
86df10e3 SP |
2163 | bool xz_p, yz_p, xyz_p; |
2164 | int step_x, step_y, step_z; | |
4839cb59 | 2165 | HOST_WIDE_INT niter_x, niter_y, niter_z, niter; |
d93817c4 ZD |
2166 | affine_fn overlaps_a_xz, overlaps_b_xz; |
2167 | affine_fn overlaps_a_yz, overlaps_b_yz; | |
2168 | affine_fn overlaps_a_xyz, overlaps_b_xyz; | |
2169 | affine_fn ova1, ova2, ovb; | |
2170 | tree last_conflicts_xz, last_conflicts_yz, last_conflicts_xyz; | |
86df10e3 | 2171 | |
6b6fa4e9 SP |
2172 | step_x = int_cst_value (CHREC_RIGHT (CHREC_LEFT (chrec_a))); |
2173 | step_y = int_cst_value (CHREC_RIGHT (chrec_a)); | |
2174 | step_z = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2175 | |
652c4c71 RG |
2176 | niter_x = max_stmt_executions_int (get_chrec_loop (CHREC_LEFT (chrec_a))); |
2177 | niter_y = max_stmt_executions_int (get_chrec_loop (chrec_a)); | |
2178 | niter_z = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
b8698a0f | 2179 | |
4839cb59 | 2180 | if (niter_x < 0 || niter_y < 0 || niter_z < 0) |
86df10e3 | 2181 | { |
0ff4040e SP |
2182 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2183 | fprintf (dump_file, "overlap steps test failed: no iteration counts.\n"); | |
b8698a0f | 2184 | |
d93817c4 ZD |
2185 | *overlaps_a = conflict_fn_not_known (); |
2186 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2187 | *last_conflicts = chrec_dont_know; |
2188 | return; | |
2189 | } | |
2190 | ||
86df10e3 SP |
2191 | niter = MIN (niter_x, niter_z); |
2192 | compute_overlap_steps_for_affine_univar (niter, step_x, step_z, | |
2193 | &overlaps_a_xz, | |
2194 | &overlaps_b_xz, | |
2195 | &last_conflicts_xz, 1); | |
2196 | niter = MIN (niter_y, niter_z); | |
2197 | compute_overlap_steps_for_affine_univar (niter, step_y, step_z, | |
2198 | &overlaps_a_yz, | |
2199 | &overlaps_b_yz, | |
2200 | &last_conflicts_yz, 2); | |
2201 | niter = MIN (niter_x, niter_z); | |
2202 | niter = MIN (niter_y, niter); | |
2203 | compute_overlap_steps_for_affine_univar (niter, step_x + step_y, step_z, | |
2204 | &overlaps_a_xyz, | |
2205 | &overlaps_b_xyz, | |
2206 | &last_conflicts_xyz, 3); | |
2207 | ||
2208 | xz_p = !integer_zerop (last_conflicts_xz); | |
2209 | yz_p = !integer_zerop (last_conflicts_yz); | |
2210 | xyz_p = !integer_zerop (last_conflicts_xyz); | |
2211 | ||
2212 | if (xz_p || yz_p || xyz_p) | |
2213 | { | |
d93817c4 ZD |
2214 | ova1 = affine_fn_cst (integer_zero_node); |
2215 | ova2 = affine_fn_cst (integer_zero_node); | |
2216 | ovb = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
2217 | if (xz_p) |
2218 | { | |
d93817c4 ZD |
2219 | affine_fn t0 = ova1; |
2220 | affine_fn t2 = ovb; | |
2221 | ||
2222 | ova1 = affine_fn_plus (ova1, overlaps_a_xz); | |
2223 | ovb = affine_fn_plus (ovb, overlaps_b_xz); | |
2224 | affine_fn_free (t0); | |
2225 | affine_fn_free (t2); | |
86df10e3 SP |
2226 | *last_conflicts = last_conflicts_xz; |
2227 | } | |
2228 | if (yz_p) | |
2229 | { | |
d93817c4 ZD |
2230 | affine_fn t0 = ova2; |
2231 | affine_fn t2 = ovb; | |
2232 | ||
2233 | ova2 = affine_fn_plus (ova2, overlaps_a_yz); | |
2234 | ovb = affine_fn_plus (ovb, overlaps_b_yz); | |
2235 | affine_fn_free (t0); | |
2236 | affine_fn_free (t2); | |
86df10e3 SP |
2237 | *last_conflicts = last_conflicts_yz; |
2238 | } | |
2239 | if (xyz_p) | |
2240 | { | |
d93817c4 ZD |
2241 | affine_fn t0 = ova1; |
2242 | affine_fn t2 = ova2; | |
2243 | affine_fn t4 = ovb; | |
2244 | ||
2245 | ova1 = affine_fn_plus (ova1, overlaps_a_xyz); | |
2246 | ova2 = affine_fn_plus (ova2, overlaps_a_xyz); | |
2247 | ovb = affine_fn_plus (ovb, overlaps_b_xyz); | |
2248 | affine_fn_free (t0); | |
2249 | affine_fn_free (t2); | |
2250 | affine_fn_free (t4); | |
86df10e3 SP |
2251 | *last_conflicts = last_conflicts_xyz; |
2252 | } | |
d93817c4 ZD |
2253 | *overlaps_a = conflict_fn (2, ova1, ova2); |
2254 | *overlaps_b = conflict_fn (1, ovb); | |
86df10e3 SP |
2255 | } |
2256 | else | |
2257 | { | |
d93817c4 ZD |
2258 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2259 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 SP |
2260 | *last_conflicts = integer_zero_node; |
2261 | } | |
d93817c4 ZD |
2262 | |
2263 | affine_fn_free (overlaps_a_xz); | |
2264 | affine_fn_free (overlaps_b_xz); | |
2265 | affine_fn_free (overlaps_a_yz); | |
2266 | affine_fn_free (overlaps_b_yz); | |
2267 | affine_fn_free (overlaps_a_xyz); | |
2268 | affine_fn_free (overlaps_b_xyz); | |
56cf8686 SP |
2269 | } |
2270 | ||
b305e3da SP |
2271 | /* Copy the elements of vector VEC1 with length SIZE to VEC2. */ |
2272 | ||
2273 | static void | |
2274 | lambda_vector_copy (lambda_vector vec1, lambda_vector vec2, | |
2275 | int size) | |
2276 | { | |
2277 | memcpy (vec2, vec1, size * sizeof (*vec1)); | |
2278 | } | |
2279 | ||
2280 | /* Copy the elements of M x N matrix MAT1 to MAT2. */ | |
2281 | ||
2282 | static void | |
2283 | lambda_matrix_copy (lambda_matrix mat1, lambda_matrix mat2, | |
2284 | int m, int n) | |
2285 | { | |
2286 | int i; | |
2287 | ||
2288 | for (i = 0; i < m; i++) | |
2289 | lambda_vector_copy (mat1[i], mat2[i], n); | |
2290 | } | |
2291 | ||
2292 | /* Store the N x N identity matrix in MAT. */ | |
2293 | ||
2294 | static void | |
2295 | lambda_matrix_id (lambda_matrix mat, int size) | |
2296 | { | |
2297 | int i, j; | |
2298 | ||
2299 | for (i = 0; i < size; i++) | |
2300 | for (j = 0; j < size; j++) | |
2301 | mat[i][j] = (i == j) ? 1 : 0; | |
2302 | } | |
2303 | ||
2304 | /* Return the first nonzero element of vector VEC1 between START and N. | |
2305 | We must have START <= N. Returns N if VEC1 is the zero vector. */ | |
2306 | ||
2307 | static int | |
2308 | lambda_vector_first_nz (lambda_vector vec1, int n, int start) | |
2309 | { | |
2310 | int j = start; | |
2311 | while (j < n && vec1[j] == 0) | |
2312 | j++; | |
2313 | return j; | |
2314 | } | |
2315 | ||
2316 | /* Add a multiple of row R1 of matrix MAT with N columns to row R2: | |
2317 | R2 = R2 + CONST1 * R1. */ | |
2318 | ||
2319 | static void | |
2320 | lambda_matrix_row_add (lambda_matrix mat, int n, int r1, int r2, int const1) | |
2321 | { | |
2322 | int i; | |
2323 | ||
2324 | if (const1 == 0) | |
2325 | return; | |
2326 | ||
2327 | for (i = 0; i < n; i++) | |
2328 | mat[r2][i] += const1 * mat[r1][i]; | |
2329 | } | |
2330 | ||
2331 | /* Swap rows R1 and R2 in matrix MAT. */ | |
2332 | ||
2333 | static void | |
2334 | lambda_matrix_row_exchange (lambda_matrix mat, int r1, int r2) | |
2335 | { | |
2336 | lambda_vector row; | |
2337 | ||
2338 | row = mat[r1]; | |
2339 | mat[r1] = mat[r2]; | |
2340 | mat[r2] = row; | |
2341 | } | |
2342 | ||
2343 | /* Multiply vector VEC1 of length SIZE by a constant CONST1, | |
2344 | and store the result in VEC2. */ | |
2345 | ||
2346 | static void | |
2347 | lambda_vector_mult_const (lambda_vector vec1, lambda_vector vec2, | |
2348 | int size, int const1) | |
2349 | { | |
2350 | int i; | |
2351 | ||
2352 | if (const1 == 0) | |
2353 | lambda_vector_clear (vec2, size); | |
2354 | else | |
2355 | for (i = 0; i < size; i++) | |
2356 | vec2[i] = const1 * vec1[i]; | |
2357 | } | |
2358 | ||
2359 | /* Negate vector VEC1 with length SIZE and store it in VEC2. */ | |
2360 | ||
2361 | static void | |
2362 | lambda_vector_negate (lambda_vector vec1, lambda_vector vec2, | |
2363 | int size) | |
2364 | { | |
2365 | lambda_vector_mult_const (vec1, vec2, size, -1); | |
2366 | } | |
2367 | ||
2368 | /* Negate row R1 of matrix MAT which has N columns. */ | |
2369 | ||
2370 | static void | |
2371 | lambda_matrix_row_negate (lambda_matrix mat, int n, int r1) | |
2372 | { | |
2373 | lambda_vector_negate (mat[r1], mat[r1], n); | |
2374 | } | |
2375 | ||
2376 | /* Return true if two vectors are equal. */ | |
2377 | ||
2378 | static bool | |
2379 | lambda_vector_equal (lambda_vector vec1, lambda_vector vec2, int size) | |
2380 | { | |
2381 | int i; | |
2382 | for (i = 0; i < size; i++) | |
2383 | if (vec1[i] != vec2[i]) | |
2384 | return false; | |
2385 | return true; | |
2386 | } | |
2387 | ||
2388 | /* Given an M x N integer matrix A, this function determines an M x | |
2389 | M unimodular matrix U, and an M x N echelon matrix S such that | |
2390 | "U.A = S". This decomposition is also known as "right Hermite". | |
2391 | ||
2392 | Ref: Algorithm 2.1 page 33 in "Loop Transformations for | |
2393 | Restructuring Compilers" Utpal Banerjee. */ | |
2394 | ||
2395 | static void | |
2396 | lambda_matrix_right_hermite (lambda_matrix A, int m, int n, | |
2397 | lambda_matrix S, lambda_matrix U) | |
2398 | { | |
2399 | int i, j, i0 = 0; | |
2400 | ||
2401 | lambda_matrix_copy (A, S, m, n); | |
2402 | lambda_matrix_id (U, m); | |
2403 | ||
2404 | for (j = 0; j < n; j++) | |
2405 | { | |
2406 | if (lambda_vector_first_nz (S[j], m, i0) < m) | |
2407 | { | |
2408 | ++i0; | |
2409 | for (i = m - 1; i >= i0; i--) | |
2410 | { | |
2411 | while (S[i][j] != 0) | |
2412 | { | |
2413 | int sigma, factor, a, b; | |
2414 | ||
2415 | a = S[i-1][j]; | |
2416 | b = S[i][j]; | |
2417 | sigma = (a * b < 0) ? -1: 1; | |
2418 | a = abs (a); | |
2419 | b = abs (b); | |
2420 | factor = sigma * (a / b); | |
2421 | ||
2422 | lambda_matrix_row_add (S, n, i, i-1, -factor); | |
2423 | lambda_matrix_row_exchange (S, i, i-1); | |
2424 | ||
2425 | lambda_matrix_row_add (U, m, i, i-1, -factor); | |
2426 | lambda_matrix_row_exchange (U, i, i-1); | |
2427 | } | |
2428 | } | |
2429 | } | |
2430 | } | |
2431 | } | |
2432 | ||
56cf8686 | 2433 | /* Determines the overlapping elements due to accesses CHREC_A and |
0ff4040e SP |
2434 | CHREC_B, that are affine functions. This function cannot handle |
2435 | symbolic evolution functions, ie. when initial conditions are | |
2436 | parameters, because it uses lambda matrices of integers. */ | |
56cf8686 SP |
2437 | |
2438 | static void | |
b8698a0f | 2439 | analyze_subscript_affine_affine (tree chrec_a, |
56cf8686 | 2440 | tree chrec_b, |
b8698a0f L |
2441 | conflict_function **overlaps_a, |
2442 | conflict_function **overlaps_b, | |
86df10e3 | 2443 | tree *last_conflicts) |
56cf8686 | 2444 | { |
86df10e3 | 2445 | unsigned nb_vars_a, nb_vars_b, dim; |
fd727b34 | 2446 | HOST_WIDE_INT init_a, init_b, gamma, gcd_alpha_beta; |
86df10e3 | 2447 | lambda_matrix A, U, S; |
f873b205 | 2448 | struct obstack scratch_obstack; |
86df10e3 | 2449 | |
e2157b49 | 2450 | if (eq_evolutions_p (chrec_a, chrec_b)) |
416f403e | 2451 | { |
e2157b49 SP |
2452 | /* The accessed index overlaps for each iteration in the |
2453 | loop. */ | |
d93817c4 ZD |
2454 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2455 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
416f403e DB |
2456 | *last_conflicts = chrec_dont_know; |
2457 | return; | |
2458 | } | |
56cf8686 SP |
2459 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2460 | fprintf (dump_file, "(analyze_subscript_affine_affine \n"); | |
b8698a0f | 2461 | |
56cf8686 SP |
2462 | /* For determining the initial intersection, we have to solve a |
2463 | Diophantine equation. This is the most time consuming part. | |
b8698a0f | 2464 | |
56cf8686 SP |
2465 | For answering to the question: "Is there a dependence?" we have |
2466 | to prove that there exists a solution to the Diophantine | |
2467 | equation, and that the solution is in the iteration domain, | |
89dbed81 | 2468 | i.e. the solution is positive or zero, and that the solution |
56cf8686 SP |
2469 | happens before the upper bound loop.nb_iterations. Otherwise |
2470 | there is no dependence. This function outputs a description of | |
2471 | the iterations that hold the intersections. */ | |
2472 | ||
86df10e3 SP |
2473 | nb_vars_a = nb_vars_in_chrec (chrec_a); |
2474 | nb_vars_b = nb_vars_in_chrec (chrec_b); | |
2475 | ||
f873b205 LB |
2476 | gcc_obstack_init (&scratch_obstack); |
2477 | ||
86df10e3 | 2478 | dim = nb_vars_a + nb_vars_b; |
f873b205 LB |
2479 | U = lambda_matrix_new (dim, dim, &scratch_obstack); |
2480 | A = lambda_matrix_new (dim, 1, &scratch_obstack); | |
2481 | S = lambda_matrix_new (dim, 1, &scratch_obstack); | |
86df10e3 | 2482 | |
5b78fc3e JS |
2483 | init_a = int_cst_value (initialize_matrix_A (A, chrec_a, 0, 1)); |
2484 | init_b = int_cst_value (initialize_matrix_A (A, chrec_b, nb_vars_a, -1)); | |
86df10e3 SP |
2485 | gamma = init_b - init_a; |
2486 | ||
2487 | /* Don't do all the hard work of solving the Diophantine equation | |
b8698a0f | 2488 | when we already know the solution: for example, |
86df10e3 SP |
2489 | | {3, +, 1}_1 |
2490 | | {3, +, 4}_2 | |
2491 | | gamma = 3 - 3 = 0. | |
b8698a0f | 2492 | Then the first overlap occurs during the first iterations: |
86df10e3 SP |
2493 | | {3, +, 1}_1 ({0, +, 4}_x) = {3, +, 4}_2 ({0, +, 1}_x) |
2494 | */ | |
2495 | if (gamma == 0) | |
56cf8686 | 2496 | { |
86df10e3 | 2497 | if (nb_vars_a == 1 && nb_vars_b == 1) |
56cf8686 | 2498 | { |
fd727b34 | 2499 | HOST_WIDE_INT step_a, step_b; |
4839cb59 | 2500 | HOST_WIDE_INT niter, niter_a, niter_b; |
d93817c4 | 2501 | affine_fn ova, ovb; |
86df10e3 | 2502 | |
652c4c71 RG |
2503 | niter_a = max_stmt_executions_int (get_chrec_loop (chrec_a)); |
2504 | niter_b = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
86df10e3 | 2505 | niter = MIN (niter_a, niter_b); |
6b6fa4e9 SP |
2506 | step_a = int_cst_value (CHREC_RIGHT (chrec_a)); |
2507 | step_b = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2508 | |
b8698a0f L |
2509 | compute_overlap_steps_for_affine_univar (niter, step_a, step_b, |
2510 | &ova, &ovb, | |
86df10e3 | 2511 | last_conflicts, 1); |
d93817c4 ZD |
2512 | *overlaps_a = conflict_fn (1, ova); |
2513 | *overlaps_b = conflict_fn (1, ovb); | |
56cf8686 | 2514 | } |
86df10e3 SP |
2515 | |
2516 | else if (nb_vars_a == 2 && nb_vars_b == 1) | |
2517 | compute_overlap_steps_for_affine_1_2 | |
2518 | (chrec_a, chrec_b, overlaps_a, overlaps_b, last_conflicts); | |
2519 | ||
2520 | else if (nb_vars_a == 1 && nb_vars_b == 2) | |
2521 | compute_overlap_steps_for_affine_1_2 | |
2522 | (chrec_b, chrec_a, overlaps_b, overlaps_a, last_conflicts); | |
2523 | ||
2524 | else | |
56cf8686 | 2525 | { |
0ff4040e SP |
2526 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2527 | fprintf (dump_file, "affine-affine test failed: too many variables.\n"); | |
d93817c4 ZD |
2528 | *overlaps_a = conflict_fn_not_known (); |
2529 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2530 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2531 | } |
0ff4040e | 2532 | goto end_analyze_subs_aa; |
86df10e3 SP |
2533 | } |
2534 | ||
2535 | /* U.A = S */ | |
2536 | lambda_matrix_right_hermite (A, dim, 1, S, U); | |
2537 | ||
2538 | if (S[0][0] < 0) | |
2539 | { | |
2540 | S[0][0] *= -1; | |
2541 | lambda_matrix_row_negate (U, dim, 0); | |
2542 | } | |
2543 | gcd_alpha_beta = S[0][0]; | |
2544 | ||
ba42e045 SP |
2545 | /* Something went wrong: for example in {1, +, 0}_5 vs. {0, +, 0}_5, |
2546 | but that is a quite strange case. Instead of ICEing, answer | |
2547 | don't know. */ | |
2548 | if (gcd_alpha_beta == 0) | |
2549 | { | |
d93817c4 ZD |
2550 | *overlaps_a = conflict_fn_not_known (); |
2551 | *overlaps_b = conflict_fn_not_known (); | |
ba42e045 SP |
2552 | *last_conflicts = chrec_dont_know; |
2553 | goto end_analyze_subs_aa; | |
2554 | } | |
2555 | ||
86df10e3 SP |
2556 | /* The classic "gcd-test". */ |
2557 | if (!int_divides_p (gcd_alpha_beta, gamma)) | |
2558 | { | |
2559 | /* The "gcd-test" has determined that there is no integer | |
2560 | solution, i.e. there is no dependence. */ | |
d93817c4 ZD |
2561 | *overlaps_a = conflict_fn_no_dependence (); |
2562 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 SP |
2563 | *last_conflicts = integer_zero_node; |
2564 | } | |
2565 | ||
2566 | /* Both access functions are univariate. This includes SIV and MIV cases. */ | |
2567 | else if (nb_vars_a == 1 && nb_vars_b == 1) | |
2568 | { | |
2569 | /* Both functions should have the same evolution sign. */ | |
2570 | if (((A[0][0] > 0 && -A[1][0] > 0) | |
2571 | || (A[0][0] < 0 && -A[1][0] < 0))) | |
56cf8686 SP |
2572 | { |
2573 | /* The solutions are given by: | |
b8698a0f | 2574 | | |
86df10e3 SP |
2575 | | [GAMMA/GCD_ALPHA_BETA t].[u11 u12] = [x0] |
2576 | | [u21 u22] [y0] | |
b8698a0f | 2577 | |
56cf8686 | 2578 | For a given integer t. Using the following variables, |
b8698a0f | 2579 | |
56cf8686 SP |
2580 | | i0 = u11 * gamma / gcd_alpha_beta |
2581 | | j0 = u12 * gamma / gcd_alpha_beta | |
2582 | | i1 = u21 | |
2583 | | j1 = u22 | |
b8698a0f | 2584 | |
56cf8686 | 2585 | the solutions are: |
b8698a0f L |
2586 | |
2587 | | x0 = i0 + i1 * t, | |
86df10e3 | 2588 | | y0 = j0 + j1 * t. */ |
2c26cbfd | 2589 | HOST_WIDE_INT i0, j0, i1, j1; |
86df10e3 SP |
2590 | |
2591 | i0 = U[0][0] * gamma / gcd_alpha_beta; | |
2592 | j0 = U[0][1] * gamma / gcd_alpha_beta; | |
2593 | i1 = U[1][0]; | |
2594 | j1 = U[1][1]; | |
2595 | ||
2596 | if ((i1 == 0 && i0 < 0) | |
2597 | || (j1 == 0 && j0 < 0)) | |
56cf8686 | 2598 | { |
b8698a0f L |
2599 | /* There is no solution. |
2600 | FIXME: The case "i0 > nb_iterations, j0 > nb_iterations" | |
2601 | falls in here, but for the moment we don't look at the | |
56cf8686 | 2602 | upper bound of the iteration domain. */ |
d93817c4 ZD |
2603 | *overlaps_a = conflict_fn_no_dependence (); |
2604 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2605 | *last_conflicts = integer_zero_node; |
2c26cbfd | 2606 | goto end_analyze_subs_aa; |
86df10e3 SP |
2607 | } |
2608 | ||
2c26cbfd | 2609 | if (i1 > 0 && j1 > 0) |
56cf8686 | 2610 | { |
652c4c71 RG |
2611 | HOST_WIDE_INT niter_a |
2612 | = max_stmt_executions_int (get_chrec_loop (chrec_a)); | |
2613 | HOST_WIDE_INT niter_b | |
2614 | = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
2c26cbfd SP |
2615 | HOST_WIDE_INT niter = MIN (niter_a, niter_b); |
2616 | ||
2617 | /* (X0, Y0) is a solution of the Diophantine equation: | |
2618 | "chrec_a (X0) = chrec_b (Y0)". */ | |
2619 | HOST_WIDE_INT tau1 = MAX (CEIL (-i0, i1), | |
2620 | CEIL (-j0, j1)); | |
2621 | HOST_WIDE_INT x0 = i1 * tau1 + i0; | |
2622 | HOST_WIDE_INT y0 = j1 * tau1 + j0; | |
2623 | ||
2624 | /* (X1, Y1) is the smallest positive solution of the eq | |
2625 | "chrec_a (X1) = chrec_b (Y1)", i.e. this is where the | |
2626 | first conflict occurs. */ | |
2627 | HOST_WIDE_INT min_multiple = MIN (x0 / i1, y0 / j1); | |
2628 | HOST_WIDE_INT x1 = x0 - i1 * min_multiple; | |
2629 | HOST_WIDE_INT y1 = y0 - j1 * min_multiple; | |
2630 | ||
2631 | if (niter > 0) | |
56cf8686 | 2632 | { |
2c26cbfd SP |
2633 | HOST_WIDE_INT tau2 = MIN (FLOOR_DIV (niter - i0, i1), |
2634 | FLOOR_DIV (niter - j0, j1)); | |
2635 | HOST_WIDE_INT last_conflict = tau2 - (x1 - i0)/i1; | |
86df10e3 | 2636 | |
2c26cbfd SP |
2637 | /* If the overlap occurs outside of the bounds of the |
2638 | loop, there is no dependence. */ | |
9e517d61 | 2639 | if (x1 >= niter || y1 >= niter) |
56cf8686 | 2640 | { |
2c26cbfd SP |
2641 | *overlaps_a = conflict_fn_no_dependence (); |
2642 | *overlaps_b = conflict_fn_no_dependence (); | |
2643 | *last_conflicts = integer_zero_node; | |
2644 | goto end_analyze_subs_aa; | |
56cf8686 SP |
2645 | } |
2646 | else | |
2c26cbfd | 2647 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); |
56cf8686 | 2648 | } |
56cf8686 | 2649 | else |
2c26cbfd SP |
2650 | *last_conflicts = chrec_dont_know; |
2651 | ||
2652 | *overlaps_a | |
2653 | = conflict_fn (1, | |
2654 | affine_fn_univar (build_int_cst (NULL_TREE, x1), | |
2655 | 1, | |
2656 | build_int_cst (NULL_TREE, i1))); | |
2657 | *overlaps_b | |
2658 | = conflict_fn (1, | |
2659 | affine_fn_univar (build_int_cst (NULL_TREE, y1), | |
2660 | 1, | |
2661 | build_int_cst (NULL_TREE, j1))); | |
2662 | } | |
2663 | else | |
2664 | { | |
2665 | /* FIXME: For the moment, the upper bound of the | |
2666 | iteration domain for i and j is not checked. */ | |
2667 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2668 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
2669 | *overlaps_a = conflict_fn_not_known (); | |
2670 | *overlaps_b = conflict_fn_not_known (); | |
2671 | *last_conflicts = chrec_dont_know; | |
56cf8686 SP |
2672 | } |
2673 | } | |
86df10e3 SP |
2674 | else |
2675 | { | |
0ff4040e SP |
2676 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2677 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2678 | *overlaps_a = conflict_fn_not_known (); |
2679 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2680 | *last_conflicts = chrec_dont_know; |
2681 | } | |
56cf8686 | 2682 | } |
56cf8686 SP |
2683 | else |
2684 | { | |
0ff4040e SP |
2685 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2686 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2687 | *overlaps_a = conflict_fn_not_known (); |
2688 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2689 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2690 | } |
86df10e3 | 2691 | |
b8698a0f | 2692 | end_analyze_subs_aa: |
f873b205 | 2693 | obstack_free (&scratch_obstack, NULL); |
56cf8686 SP |
2694 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2695 | { | |
2696 | fprintf (dump_file, " (overlaps_a = "); | |
d93817c4 | 2697 | dump_conflict_function (dump_file, *overlaps_a); |
56cf8686 | 2698 | fprintf (dump_file, ")\n (overlaps_b = "); |
d93817c4 | 2699 | dump_conflict_function (dump_file, *overlaps_b); |
bcf1ef00 | 2700 | fprintf (dump_file, "))\n"); |
56cf8686 | 2701 | } |
0ff4040e SP |
2702 | } |
2703 | ||
2704 | /* Returns true when analyze_subscript_affine_affine can be used for | |
2705 | determining the dependence relation between chrec_a and chrec_b, | |
2706 | that contain symbols. This function modifies chrec_a and chrec_b | |
2707 | such that the analysis result is the same, and such that they don't | |
b8698a0f | 2708 | contain symbols, and then can safely be passed to the analyzer. |
0ff4040e SP |
2709 | |
2710 | Example: The analysis of the following tuples of evolutions produce | |
2711 | the same results: {x+1, +, 1}_1 vs. {x+3, +, 1}_1, and {-2, +, 1}_1 | |
2712 | vs. {0, +, 1}_1 | |
b8698a0f | 2713 | |
0ff4040e SP |
2714 | {x+1, +, 1}_1 ({2, +, 1}_1) = {x+3, +, 1}_1 ({0, +, 1}_1) |
2715 | {-2, +, 1}_1 ({2, +, 1}_1) = {0, +, 1}_1 ({0, +, 1}_1) | |
2716 | */ | |
2717 | ||
2718 | static bool | |
2719 | can_use_analyze_subscript_affine_affine (tree *chrec_a, tree *chrec_b) | |
2720 | { | |
16a2acea | 2721 | tree diff, type, left_a, left_b, right_b; |
0ff4040e SP |
2722 | |
2723 | if (chrec_contains_symbols (CHREC_RIGHT (*chrec_a)) | |
2724 | || chrec_contains_symbols (CHREC_RIGHT (*chrec_b))) | |
2725 | /* FIXME: For the moment not handled. Might be refined later. */ | |
2726 | return false; | |
2727 | ||
16a2acea SP |
2728 | type = chrec_type (*chrec_a); |
2729 | left_a = CHREC_LEFT (*chrec_a); | |
726a989a | 2730 | left_b = chrec_convert (type, CHREC_LEFT (*chrec_b), NULL); |
16a2acea SP |
2731 | diff = chrec_fold_minus (type, left_a, left_b); |
2732 | ||
0ff4040e SP |
2733 | if (!evolution_function_is_constant_p (diff)) |
2734 | return false; | |
2735 | ||
56cf8686 | 2736 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e SP |
2737 | fprintf (dump_file, "can_use_subscript_aff_aff_for_symbolic \n"); |
2738 | ||
b8698a0f | 2739 | *chrec_a = build_polynomial_chrec (CHREC_VARIABLE (*chrec_a), |
0ff4040e | 2740 | diff, CHREC_RIGHT (*chrec_a)); |
726a989a | 2741 | right_b = chrec_convert (type, CHREC_RIGHT (*chrec_b), NULL); |
0ff4040e | 2742 | *chrec_b = build_polynomial_chrec (CHREC_VARIABLE (*chrec_b), |
dc61cc6b | 2743 | build_int_cst (type, 0), |
16a2acea | 2744 | right_b); |
0ff4040e | 2745 | return true; |
56cf8686 SP |
2746 | } |
2747 | ||
2748 | /* Analyze a SIV (Single Index Variable) subscript. *OVERLAPS_A and | |
2749 | *OVERLAPS_B are initialized to the functions that describe the | |
2750 | relation between the elements accessed twice by CHREC_A and | |
2751 | CHREC_B. For k >= 0, the following property is verified: | |
2752 | ||
2753 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2754 | ||
2755 | static void | |
b8698a0f | 2756 | analyze_siv_subscript (tree chrec_a, |
56cf8686 | 2757 | tree chrec_b, |
b8698a0f L |
2758 | conflict_function **overlaps_a, |
2759 | conflict_function **overlaps_b, | |
5b78fc3e JS |
2760 | tree *last_conflicts, |
2761 | int loop_nest_num) | |
56cf8686 | 2762 | { |
0ff4040e | 2763 | dependence_stats.num_siv++; |
b8698a0f | 2764 | |
56cf8686 SP |
2765 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2766 | fprintf (dump_file, "(analyze_siv_subscript \n"); | |
b8698a0f | 2767 | |
56cf8686 | 2768 | if (evolution_function_is_constant_p (chrec_a) |
5b78fc3e | 2769 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) |
b8698a0f | 2770 | analyze_siv_subscript_cst_affine (chrec_a, chrec_b, |
86df10e3 | 2771 | overlaps_a, overlaps_b, last_conflicts); |
b8698a0f | 2772 | |
5b78fc3e | 2773 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
56cf8686 | 2774 | && evolution_function_is_constant_p (chrec_b)) |
b8698a0f | 2775 | analyze_siv_subscript_cst_affine (chrec_b, chrec_a, |
86df10e3 | 2776 | overlaps_b, overlaps_a, last_conflicts); |
b8698a0f | 2777 | |
5b78fc3e JS |
2778 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
2779 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) | |
0ff4040e SP |
2780 | { |
2781 | if (!chrec_contains_symbols (chrec_a) | |
2782 | && !chrec_contains_symbols (chrec_b)) | |
2783 | { | |
b8698a0f L |
2784 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2785 | overlaps_a, overlaps_b, | |
0ff4040e SP |
2786 | last_conflicts); |
2787 | ||
d93817c4 ZD |
2788 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2789 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2790 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2791 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2792 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2793 | dependence_stats.num_siv_independent++; |
2794 | else | |
2795 | dependence_stats.num_siv_dependent++; | |
2796 | } | |
b8698a0f | 2797 | else if (can_use_analyze_subscript_affine_affine (&chrec_a, |
0ff4040e SP |
2798 | &chrec_b)) |
2799 | { | |
b8698a0f L |
2800 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2801 | overlaps_a, overlaps_b, | |
0ff4040e | 2802 | last_conflicts); |
0ff4040e | 2803 | |
d93817c4 ZD |
2804 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2805 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2806 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2807 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2808 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2809 | dependence_stats.num_siv_independent++; |
2810 | else | |
2811 | dependence_stats.num_siv_dependent++; | |
2812 | } | |
2813 | else | |
2814 | goto siv_subscript_dontknow; | |
2815 | } | |
2816 | ||
56cf8686 SP |
2817 | else |
2818 | { | |
0ff4040e SP |
2819 | siv_subscript_dontknow:; |
2820 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
bcf1ef00 | 2821 | fprintf (dump_file, " siv test failed: unimplemented"); |
d93817c4 ZD |
2822 | *overlaps_a = conflict_fn_not_known (); |
2823 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2824 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2825 | dependence_stats.num_siv_unimplemented++; |
56cf8686 | 2826 | } |
b8698a0f | 2827 | |
56cf8686 SP |
2828 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2829 | fprintf (dump_file, ")\n"); | |
2830 | } | |
2831 | ||
55a700ac ZD |
2832 | /* Returns false if we can prove that the greatest common divisor of the steps |
2833 | of CHREC does not divide CST, false otherwise. */ | |
56cf8686 SP |
2834 | |
2835 | static bool | |
ed7a4b4b | 2836 | gcd_of_steps_may_divide_p (const_tree chrec, const_tree cst) |
56cf8686 | 2837 | { |
55a700ac ZD |
2838 | HOST_WIDE_INT cd = 0, val; |
2839 | tree step; | |
0ff4040e | 2840 | |
55a700ac ZD |
2841 | if (!host_integerp (cst, 0)) |
2842 | return true; | |
2843 | val = tree_low_cst (cst, 0); | |
2844 | ||
2845 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC) | |
2846 | { | |
2847 | step = CHREC_RIGHT (chrec); | |
2848 | if (!host_integerp (step, 0)) | |
2849 | return true; | |
2850 | cd = gcd (cd, tree_low_cst (step, 0)); | |
2851 | chrec = CHREC_LEFT (chrec); | |
56cf8686 | 2852 | } |
55a700ac ZD |
2853 | |
2854 | return val % cd == 0; | |
56cf8686 SP |
2855 | } |
2856 | ||
da9a21f4 SP |
2857 | /* Analyze a MIV (Multiple Index Variable) subscript with respect to |
2858 | LOOP_NEST. *OVERLAPS_A and *OVERLAPS_B are initialized to the | |
2859 | functions that describe the relation between the elements accessed | |
2860 | twice by CHREC_A and CHREC_B. For k >= 0, the following property | |
2861 | is verified: | |
56cf8686 SP |
2862 | |
2863 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2864 | ||
2865 | static void | |
b8698a0f L |
2866 | analyze_miv_subscript (tree chrec_a, |
2867 | tree chrec_b, | |
2868 | conflict_function **overlaps_a, | |
2869 | conflict_function **overlaps_b, | |
da9a21f4 SP |
2870 | tree *last_conflicts, |
2871 | struct loop *loop_nest) | |
56cf8686 | 2872 | { |
33b30201 SP |
2873 | tree type, difference; |
2874 | ||
0ff4040e | 2875 | dependence_stats.num_miv++; |
56cf8686 SP |
2876 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2877 | fprintf (dump_file, "(analyze_miv_subscript \n"); | |
e2157b49 | 2878 | |
33b30201 | 2879 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
2880 | chrec_a = chrec_convert (type, chrec_a, NULL); |
2881 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 2882 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
b8698a0f | 2883 | |
e2157b49 | 2884 | if (eq_evolutions_p (chrec_a, chrec_b)) |
56cf8686 SP |
2885 | { |
2886 | /* Access functions are the same: all the elements are accessed | |
2887 | in the same order. */ | |
d93817c4 ZD |
2888 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2889 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
b4a9343c | 2890 | *last_conflicts = max_stmt_executions_tree (get_chrec_loop (chrec_a)); |
0ff4040e | 2891 | dependence_stats.num_miv_dependent++; |
56cf8686 | 2892 | } |
b8698a0f | 2893 | |
56cf8686 SP |
2894 | else if (evolution_function_is_constant_p (difference) |
2895 | /* For the moment, the following is verified: | |
da9a21f4 SP |
2896 | evolution_function_is_affine_multivariate_p (chrec_a, |
2897 | loop_nest->num) */ | |
55a700ac | 2898 | && !gcd_of_steps_may_divide_p (chrec_a, difference)) |
56cf8686 SP |
2899 | { |
2900 | /* testsuite/.../ssa-chrec-33.c | |
b8698a0f L |
2901 | {{21, +, 2}_1, +, -2}_2 vs. {{20, +, 2}_1, +, -2}_2 |
2902 | ||
55a700ac ZD |
2903 | The difference is 1, and all the evolution steps are multiples |
2904 | of 2, consequently there are no overlapping elements. */ | |
d93817c4 ZD |
2905 | *overlaps_a = conflict_fn_no_dependence (); |
2906 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2907 | *last_conflicts = integer_zero_node; |
0ff4040e | 2908 | dependence_stats.num_miv_independent++; |
56cf8686 | 2909 | } |
b8698a0f | 2910 | |
da9a21f4 | 2911 | else if (evolution_function_is_affine_multivariate_p (chrec_a, loop_nest->num) |
0ff4040e | 2912 | && !chrec_contains_symbols (chrec_a) |
da9a21f4 | 2913 | && evolution_function_is_affine_multivariate_p (chrec_b, loop_nest->num) |
0ff4040e | 2914 | && !chrec_contains_symbols (chrec_b)) |
56cf8686 SP |
2915 | { |
2916 | /* testsuite/.../ssa-chrec-35.c | |
2917 | {0, +, 1}_2 vs. {0, +, 1}_3 | |
2918 | the overlapping elements are respectively located at iterations: | |
b8698a0f L |
2919 | {0, +, 1}_x and {0, +, 1}_x, |
2920 | in other words, we have the equality: | |
86df10e3 | 2921 | {0, +, 1}_2 ({0, +, 1}_x) = {0, +, 1}_3 ({0, +, 1}_x) |
b8698a0f L |
2922 | |
2923 | Other examples: | |
2924 | {{0, +, 1}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) = | |
86df10e3 SP |
2925 | {0, +, 1}_1 ({{0, +, 1}_x, +, 2}_y) |
2926 | ||
b8698a0f | 2927 | {{0, +, 2}_1, +, 3}_2 ({0, +, 1}_y, {0, +, 1}_x) = |
86df10e3 | 2928 | {{0, +, 3}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) |
56cf8686 | 2929 | */ |
b8698a0f | 2930 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
86df10e3 | 2931 | overlaps_a, overlaps_b, last_conflicts); |
0ff4040e | 2932 | |
d93817c4 ZD |
2933 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2934 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2935 | dependence_stats.num_miv_unimplemented++; |
d93817c4 ZD |
2936 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2937 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2938 | dependence_stats.num_miv_independent++; |
2939 | else | |
2940 | dependence_stats.num_miv_dependent++; | |
56cf8686 | 2941 | } |
b8698a0f | 2942 | |
56cf8686 SP |
2943 | else |
2944 | { | |
2945 | /* When the analysis is too difficult, answer "don't know". */ | |
0ff4040e SP |
2946 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2947 | fprintf (dump_file, "analyze_miv_subscript test failed: unimplemented.\n"); | |
2948 | ||
d93817c4 ZD |
2949 | *overlaps_a = conflict_fn_not_known (); |
2950 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2951 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2952 | dependence_stats.num_miv_unimplemented++; |
56cf8686 | 2953 | } |
b8698a0f | 2954 | |
56cf8686 SP |
2955 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2956 | fprintf (dump_file, ")\n"); | |
2957 | } | |
2958 | ||
da9a21f4 SP |
2959 | /* Determines the iterations for which CHREC_A is equal to CHREC_B in |
2960 | with respect to LOOP_NEST. OVERLAP_ITERATIONS_A and | |
2961 | OVERLAP_ITERATIONS_B are initialized with two functions that | |
2962 | describe the iterations that contain conflicting elements. | |
b8698a0f | 2963 | |
56cf8686 | 2964 | Remark: For an integer k >= 0, the following equality is true: |
b8698a0f | 2965 | |
56cf8686 SP |
2966 | CHREC_A (OVERLAP_ITERATIONS_A (k)) == CHREC_B (OVERLAP_ITERATIONS_B (k)). |
2967 | */ | |
2968 | ||
b8698a0f L |
2969 | static void |
2970 | analyze_overlapping_iterations (tree chrec_a, | |
2971 | tree chrec_b, | |
2972 | conflict_function **overlap_iterations_a, | |
2973 | conflict_function **overlap_iterations_b, | |
da9a21f4 | 2974 | tree *last_conflicts, struct loop *loop_nest) |
56cf8686 | 2975 | { |
da9a21f4 SP |
2976 | unsigned int lnn = loop_nest->num; |
2977 | ||
0ff4040e | 2978 | dependence_stats.num_subscript_tests++; |
b8698a0f | 2979 | |
56cf8686 SP |
2980 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2981 | { | |
2982 | fprintf (dump_file, "(analyze_overlapping_iterations \n"); | |
2983 | fprintf (dump_file, " (chrec_a = "); | |
2984 | print_generic_expr (dump_file, chrec_a, 0); | |
0ff4040e | 2985 | fprintf (dump_file, ")\n (chrec_b = "); |
56cf8686 SP |
2986 | print_generic_expr (dump_file, chrec_b, 0); |
2987 | fprintf (dump_file, ")\n"); | |
2988 | } | |
0ff4040e | 2989 | |
56cf8686 SP |
2990 | if (chrec_a == NULL_TREE |
2991 | || chrec_b == NULL_TREE | |
2992 | || chrec_contains_undetermined (chrec_a) | |
0ff4040e | 2993 | || chrec_contains_undetermined (chrec_b)) |
56cf8686 | 2994 | { |
0ff4040e | 2995 | dependence_stats.num_subscript_undetermined++; |
b8698a0f | 2996 | |
d93817c4 ZD |
2997 | *overlap_iterations_a = conflict_fn_not_known (); |
2998 | *overlap_iterations_b = conflict_fn_not_known (); | |
56cf8686 | 2999 | } |
0ff4040e | 3000 | |
b8698a0f | 3001 | /* If they are the same chrec, and are affine, they overlap |
0ff4040e SP |
3002 | on every iteration. */ |
3003 | else if (eq_evolutions_p (chrec_a, chrec_b) | |
3e6f8b56 SP |
3004 | && (evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
3005 | || operand_equal_p (chrec_a, chrec_b, 0))) | |
0ff4040e SP |
3006 | { |
3007 | dependence_stats.num_same_subscript_function++; | |
d93817c4 ZD |
3008 | *overlap_iterations_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
3009 | *overlap_iterations_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
0ff4040e SP |
3010 | *last_conflicts = chrec_dont_know; |
3011 | } | |
3012 | ||
3013 | /* If they aren't the same, and aren't affine, we can't do anything | |
3e6f8b56 | 3014 | yet. */ |
b8698a0f | 3015 | else if ((chrec_contains_symbols (chrec_a) |
0ff4040e | 3016 | || chrec_contains_symbols (chrec_b)) |
da9a21f4 SP |
3017 | && (!evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
3018 | || !evolution_function_is_affine_multivariate_p (chrec_b, lnn))) | |
0ff4040e SP |
3019 | { |
3020 | dependence_stats.num_subscript_undetermined++; | |
d93817c4 ZD |
3021 | *overlap_iterations_a = conflict_fn_not_known (); |
3022 | *overlap_iterations_b = conflict_fn_not_known (); | |
0ff4040e SP |
3023 | } |
3024 | ||
56cf8686 | 3025 | else if (ziv_subscript_p (chrec_a, chrec_b)) |
b8698a0f | 3026 | analyze_ziv_subscript (chrec_a, chrec_b, |
86df10e3 SP |
3027 | overlap_iterations_a, overlap_iterations_b, |
3028 | last_conflicts); | |
b8698a0f | 3029 | |
56cf8686 | 3030 | else if (siv_subscript_p (chrec_a, chrec_b)) |
b8698a0f L |
3031 | analyze_siv_subscript (chrec_a, chrec_b, |
3032 | overlap_iterations_a, overlap_iterations_b, | |
5b78fc3e | 3033 | last_conflicts, lnn); |
b8698a0f | 3034 | |
56cf8686 | 3035 | else |
b8698a0f | 3036 | analyze_miv_subscript (chrec_a, chrec_b, |
86df10e3 | 3037 | overlap_iterations_a, overlap_iterations_b, |
da9a21f4 | 3038 | last_conflicts, loop_nest); |
b8698a0f | 3039 | |
56cf8686 SP |
3040 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3041 | { | |
3042 | fprintf (dump_file, " (overlap_iterations_a = "); | |
d93817c4 | 3043 | dump_conflict_function (dump_file, *overlap_iterations_a); |
56cf8686 | 3044 | fprintf (dump_file, ")\n (overlap_iterations_b = "); |
d93817c4 | 3045 | dump_conflict_function (dump_file, *overlap_iterations_b); |
bcf1ef00 | 3046 | fprintf (dump_file, "))\n"); |
56cf8686 SP |
3047 | } |
3048 | } | |
3049 | ||
ba42e045 | 3050 | /* Helper function for uniquely inserting distance vectors. */ |
56cf8686 | 3051 | |
ba42e045 SP |
3052 | static void |
3053 | save_dist_v (struct data_dependence_relation *ddr, lambda_vector dist_v) | |
3054 | { | |
3055 | unsigned i; | |
3056 | lambda_vector v; | |
56cf8686 | 3057 | |
9771b263 | 3058 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, v) |
ba42e045 SP |
3059 | if (lambda_vector_equal (v, dist_v, DDR_NB_LOOPS (ddr))) |
3060 | return; | |
56cf8686 | 3061 | |
9771b263 | 3062 | DDR_DIST_VECTS (ddr).safe_push (dist_v); |
ba42e045 | 3063 | } |
56cf8686 | 3064 | |
ba42e045 SP |
3065 | /* Helper function for uniquely inserting direction vectors. */ |
3066 | ||
3067 | static void | |
3068 | save_dir_v (struct data_dependence_relation *ddr, lambda_vector dir_v) | |
56cf8686 SP |
3069 | { |
3070 | unsigned i; | |
ba42e045 | 3071 | lambda_vector v; |
0ff4040e | 3072 | |
9771b263 | 3073 | FOR_EACH_VEC_ELT (DDR_DIR_VECTS (ddr), i, v) |
ba42e045 SP |
3074 | if (lambda_vector_equal (v, dir_v, DDR_NB_LOOPS (ddr))) |
3075 | return; | |
3076 | ||
9771b263 | 3077 | DDR_DIR_VECTS (ddr).safe_push (dir_v); |
ba42e045 SP |
3078 | } |
3079 | ||
3080 | /* Add a distance of 1 on all the loops outer than INDEX. If we | |
3081 | haven't yet determined a distance for this outer loop, push a new | |
3082 | distance vector composed of the previous distance, and a distance | |
3083 | of 1 for this outer loop. Example: | |
3084 | ||
3085 | | loop_1 | |
3086 | | loop_2 | |
3087 | | A[10] | |
3088 | | endloop_2 | |
3089 | | endloop_1 | |
3090 | ||
3091 | Saved vectors are of the form (dist_in_1, dist_in_2). First, we | |
3092 | save (0, 1), then we have to save (1, 0). */ | |
3093 | ||
3094 | static void | |
3095 | add_outer_distances (struct data_dependence_relation *ddr, | |
3096 | lambda_vector dist_v, int index) | |
3097 | { | |
3098 | /* For each outer loop where init_v is not set, the accesses are | |
3099 | in dependence of distance 1 in the loop. */ | |
3100 | while (--index >= 0) | |
3101 | { | |
3102 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3103 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
3104 | save_v[index] = 1; | |
3105 | save_dist_v (ddr, save_v); | |
3106 | } | |
3107 | } | |
3108 | ||
3109 | /* Return false when fail to represent the data dependence as a | |
3110 | distance vector. INIT_B is set to true when a component has been | |
3111 | added to the distance vector DIST_V. INDEX_CARRY is then set to | |
3112 | the index in DIST_V that carries the dependence. */ | |
3113 | ||
3114 | static bool | |
3115 | build_classic_dist_vector_1 (struct data_dependence_relation *ddr, | |
3116 | struct data_reference *ddr_a, | |
3117 | struct data_reference *ddr_b, | |
3118 | lambda_vector dist_v, bool *init_b, | |
3119 | int *index_carry) | |
3120 | { | |
3121 | unsigned i; | |
3122 | lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
0ff4040e | 3123 | |
36d59cf7 | 3124 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
56cf8686 | 3125 | { |
86df10e3 | 3126 | tree access_fn_a, access_fn_b; |
36d59cf7 | 3127 | struct subscript *subscript = DDR_SUBSCRIPT (ddr, i); |
56cf8686 SP |
3128 | |
3129 | if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
3130 | { |
3131 | non_affine_dependence_relation (ddr); | |
ba42e045 | 3132 | return false; |
86df10e3 SP |
3133 | } |
3134 | ||
ba42e045 SP |
3135 | access_fn_a = DR_ACCESS_FN (ddr_a, i); |
3136 | access_fn_b = DR_ACCESS_FN (ddr_b, i); | |
56cf8686 | 3137 | |
b8698a0f | 3138 | if (TREE_CODE (access_fn_a) == POLYNOMIAL_CHREC |
86df10e3 | 3139 | && TREE_CODE (access_fn_b) == POLYNOMIAL_CHREC) |
56cf8686 | 3140 | { |
ba42e045 | 3141 | int dist, index; |
a130584a SP |
3142 | int var_a = CHREC_VARIABLE (access_fn_a); |
3143 | int var_b = CHREC_VARIABLE (access_fn_b); | |
ba42e045 | 3144 | |
a130584a SP |
3145 | if (var_a != var_b |
3146 | || chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
3147 | { |
3148 | non_affine_dependence_relation (ddr); | |
ba42e045 | 3149 | return false; |
86df10e3 | 3150 | } |
b8698a0f | 3151 | |
6b6fa4e9 | 3152 | dist = int_cst_value (SUB_DISTANCE (subscript)); |
a130584a SP |
3153 | index = index_in_loop_nest (var_a, DDR_LOOP_NEST (ddr)); |
3154 | *index_carry = MIN (index, *index_carry); | |
56cf8686 | 3155 | |
ba42e045 SP |
3156 | /* This is the subscript coupling test. If we have already |
3157 | recorded a distance for this loop (a distance coming from | |
3158 | another subscript), it should be the same. For example, | |
3159 | in the following code, there is no dependence: | |
3160 | ||
56cf8686 SP |
3161 | | loop i = 0, N, 1 |
3162 | | T[i+1][i] = ... | |
3163 | | ... = T[i][i] | |
3164 | | endloop | |
ba42e045 SP |
3165 | */ |
3166 | if (init_v[index] != 0 && dist_v[index] != dist) | |
56cf8686 | 3167 | { |
36d59cf7 | 3168 | finalize_ddr_dependent (ddr, chrec_known); |
ba42e045 | 3169 | return false; |
56cf8686 SP |
3170 | } |
3171 | ||
ba42e045 SP |
3172 | dist_v[index] = dist; |
3173 | init_v[index] = 1; | |
3174 | *init_b = true; | |
3175 | } | |
a50411de | 3176 | else if (!operand_equal_p (access_fn_a, access_fn_b, 0)) |
ba42e045 SP |
3177 | { |
3178 | /* This can be for example an affine vs. constant dependence | |
3179 | (T[i] vs. T[3]) that is not an affine dependence and is | |
3180 | not representable as a distance vector. */ | |
3181 | non_affine_dependence_relation (ddr); | |
3182 | return false; | |
56cf8686 SP |
3183 | } |
3184 | } | |
304afda6 | 3185 | |
ba42e045 SP |
3186 | return true; |
3187 | } | |
304afda6 | 3188 | |
1baf2906 SP |
3189 | /* Return true when the DDR contains only constant access functions. */ |
3190 | ||
3191 | static bool | |
ed7a4b4b | 3192 | constant_access_functions (const struct data_dependence_relation *ddr) |
1baf2906 SP |
3193 | { |
3194 | unsigned i; | |
3195 | ||
3196 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3197 | if (!evolution_function_is_constant_p (DR_ACCESS_FN (DDR_A (ddr), i)) | |
3198 | || !evolution_function_is_constant_p (DR_ACCESS_FN (DDR_B (ddr), i))) | |
3199 | return false; | |
3200 | ||
3201 | return true; | |
3202 | } | |
3203 | ||
ba42e045 | 3204 | /* Helper function for the case where DDR_A and DDR_B are the same |
097392de SP |
3205 | multivariate access function with a constant step. For an example |
3206 | see pr34635-1.c. */ | |
86df10e3 | 3207 | |
ba42e045 SP |
3208 | static void |
3209 | add_multivariate_self_dist (struct data_dependence_relation *ddr, tree c_2) | |
3210 | { | |
3211 | int x_1, x_2; | |
3212 | tree c_1 = CHREC_LEFT (c_2); | |
3213 | tree c_0 = CHREC_LEFT (c_1); | |
3214 | lambda_vector dist_v; | |
0ca2faee | 3215 | int v1, v2, cd; |
86df10e3 | 3216 | |
b1e75954 SP |
3217 | /* Polynomials with more than 2 variables are not handled yet. When |
3218 | the evolution steps are parameters, it is not possible to | |
3219 | represent the dependence using classical distance vectors. */ | |
3220 | if (TREE_CODE (c_0) != INTEGER_CST | |
3221 | || TREE_CODE (CHREC_RIGHT (c_1)) != INTEGER_CST | |
3222 | || TREE_CODE (CHREC_RIGHT (c_2)) != INTEGER_CST) | |
3223 | { | |
3224 | DDR_AFFINE_P (ddr) = false; | |
ba42e045 SP |
3225 | return; |
3226 | } | |
304afda6 | 3227 | |
ba42e045 SP |
3228 | x_2 = index_in_loop_nest (CHREC_VARIABLE (c_2), DDR_LOOP_NEST (ddr)); |
3229 | x_1 = index_in_loop_nest (CHREC_VARIABLE (c_1), DDR_LOOP_NEST (ddr)); | |
304afda6 | 3230 | |
ba42e045 SP |
3231 | /* For "{{0, +, 2}_1, +, 3}_2" the distance vector is (3, -2). */ |
3232 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
6b6fa4e9 SP |
3233 | v1 = int_cst_value (CHREC_RIGHT (c_1)); |
3234 | v2 = int_cst_value (CHREC_RIGHT (c_2)); | |
0ca2faee ZD |
3235 | cd = gcd (v1, v2); |
3236 | v1 /= cd; | |
3237 | v2 /= cd; | |
3238 | ||
3239 | if (v2 < 0) | |
3240 | { | |
3241 | v2 = -v2; | |
3242 | v1 = -v1; | |
3243 | } | |
3244 | ||
3245 | dist_v[x_1] = v2; | |
3246 | dist_v[x_2] = -v1; | |
ba42e045 | 3247 | save_dist_v (ddr, dist_v); |
304afda6 | 3248 | |
ba42e045 SP |
3249 | add_outer_distances (ddr, dist_v, x_1); |
3250 | } | |
304afda6 | 3251 | |
ba42e045 SP |
3252 | /* Helper function for the case where DDR_A and DDR_B are the same |
3253 | access functions. */ | |
37b8a73b | 3254 | |
ba42e045 SP |
3255 | static void |
3256 | add_other_self_distances (struct data_dependence_relation *ddr) | |
3257 | { | |
3258 | lambda_vector dist_v; | |
3259 | unsigned i; | |
3260 | int index_carry = DDR_NB_LOOPS (ddr); | |
304afda6 | 3261 | |
ba42e045 | 3262 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
37b8a73b | 3263 | { |
ba42e045 | 3264 | tree access_fun = DR_ACCESS_FN (DDR_A (ddr), i); |
304afda6 | 3265 | |
ba42e045 | 3266 | if (TREE_CODE (access_fun) == POLYNOMIAL_CHREC) |
304afda6 | 3267 | { |
ba42e045 SP |
3268 | if (!evolution_function_is_univariate_p (access_fun)) |
3269 | { | |
3270 | if (DDR_NUM_SUBSCRIPTS (ddr) != 1) | |
3271 | { | |
3272 | DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; | |
3273 | return; | |
3274 | } | |
3275 | ||
097392de SP |
3276 | access_fun = DR_ACCESS_FN (DDR_A (ddr), 0); |
3277 | ||
3278 | if (TREE_CODE (CHREC_LEFT (access_fun)) == POLYNOMIAL_CHREC) | |
3279 | add_multivariate_self_dist (ddr, access_fun); | |
3280 | else | |
3281 | /* The evolution step is not constant: it varies in | |
3282 | the outer loop, so this cannot be represented by a | |
3283 | distance vector. For example in pr34635.c the | |
3284 | evolution is {0, +, {0, +, 4}_1}_2. */ | |
3285 | DDR_AFFINE_P (ddr) = false; | |
3286 | ||
ba42e045 SP |
3287 | return; |
3288 | } | |
3289 | ||
3290 | index_carry = MIN (index_carry, | |
3291 | index_in_loop_nest (CHREC_VARIABLE (access_fun), | |
3292 | DDR_LOOP_NEST (ddr))); | |
304afda6 | 3293 | } |
37b8a73b SP |
3294 | } |
3295 | ||
ba42e045 SP |
3296 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3297 | add_outer_distances (ddr, dist_v, index_carry); | |
56cf8686 SP |
3298 | } |
3299 | ||
1baf2906 SP |
3300 | static void |
3301 | insert_innermost_unit_dist_vector (struct data_dependence_relation *ddr) | |
3302 | { | |
3303 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3304 | ||
3305 | dist_v[DDR_INNER_LOOP (ddr)] = 1; | |
3306 | save_dist_v (ddr, dist_v); | |
3307 | } | |
3308 | ||
3309 | /* Adds a unit distance vector to DDR when there is a 0 overlap. This | |
3310 | is the case for example when access functions are the same and | |
3311 | equal to a constant, as in: | |
3312 | ||
3313 | | loop_1 | |
3314 | | A[3] = ... | |
3315 | | ... = A[3] | |
3316 | | endloop_1 | |
3317 | ||
3318 | in which case the distance vectors are (0) and (1). */ | |
3319 | ||
3320 | static void | |
3321 | add_distance_for_zero_overlaps (struct data_dependence_relation *ddr) | |
3322 | { | |
3323 | unsigned i, j; | |
3324 | ||
3325 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3326 | { | |
3327 | subscript_p sub = DDR_SUBSCRIPT (ddr, i); | |
3328 | conflict_function *ca = SUB_CONFLICTS_IN_A (sub); | |
3329 | conflict_function *cb = SUB_CONFLICTS_IN_B (sub); | |
3330 | ||
3331 | for (j = 0; j < ca->n; j++) | |
3332 | if (affine_function_zero_p (ca->fns[j])) | |
3333 | { | |
3334 | insert_innermost_unit_dist_vector (ddr); | |
3335 | return; | |
3336 | } | |
3337 | ||
3338 | for (j = 0; j < cb->n; j++) | |
3339 | if (affine_function_zero_p (cb->fns[j])) | |
3340 | { | |
3341 | insert_innermost_unit_dist_vector (ddr); | |
3342 | return; | |
3343 | } | |
3344 | } | |
3345 | } | |
3346 | ||
ba42e045 SP |
3347 | /* Compute the classic per loop distance vector. DDR is the data |
3348 | dependence relation to build a vector from. Return false when fail | |
3349 | to represent the data dependence as a distance vector. */ | |
56cf8686 | 3350 | |
464f49d8 | 3351 | static bool |
da9a21f4 SP |
3352 | build_classic_dist_vector (struct data_dependence_relation *ddr, |
3353 | struct loop *loop_nest) | |
56cf8686 | 3354 | { |
304afda6 | 3355 | bool init_b = false; |
ba42e045 SP |
3356 | int index_carry = DDR_NB_LOOPS (ddr); |
3357 | lambda_vector dist_v; | |
304afda6 | 3358 | |
36d59cf7 | 3359 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
2f470326 | 3360 | return false; |
ba42e045 SP |
3361 | |
3362 | if (same_access_functions (ddr)) | |
56cf8686 | 3363 | { |
ba42e045 SP |
3364 | /* Save the 0 vector. */ |
3365 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3366 | save_dist_v (ddr, dist_v); | |
56cf8686 | 3367 | |
1baf2906 SP |
3368 | if (constant_access_functions (ddr)) |
3369 | add_distance_for_zero_overlaps (ddr); | |
3370 | ||
ba42e045 SP |
3371 | if (DDR_NB_LOOPS (ddr) > 1) |
3372 | add_other_self_distances (ddr); | |
86df10e3 | 3373 | |
ba42e045 SP |
3374 | return true; |
3375 | } | |
86df10e3 | 3376 | |
ba42e045 SP |
3377 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3378 | if (!build_classic_dist_vector_1 (ddr, DDR_A (ddr), DDR_B (ddr), | |
3379 | dist_v, &init_b, &index_carry)) | |
3380 | return false; | |
86df10e3 | 3381 | |
ba42e045 SP |
3382 | /* Save the distance vector if we initialized one. */ |
3383 | if (init_b) | |
3384 | { | |
3385 | /* Verify a basic constraint: classic distance vectors should | |
3386 | always be lexicographically positive. | |
3387 | ||
3388 | Data references are collected in the order of execution of | |
3389 | the program, thus for the following loop | |
3390 | ||
3391 | | for (i = 1; i < 100; i++) | |
3392 | | for (j = 1; j < 100; j++) | |
3393 | | { | |
3394 | | t = T[j+1][i-1]; // A | |
3395 | | T[j][i] = t + 2; // B | |
3396 | | } | |
3397 | ||
3398 | references are collected following the direction of the wind: | |
3399 | A then B. The data dependence tests are performed also | |
3400 | following this order, such that we're looking at the distance | |
3401 | separating the elements accessed by A from the elements later | |
3402 | accessed by B. But in this example, the distance returned by | |
3403 | test_dep (A, B) is lexicographically negative (-1, 1), that | |
3404 | means that the access A occurs later than B with respect to | |
3405 | the outer loop, ie. we're actually looking upwind. In this | |
3406 | case we solve test_dep (B, A) looking downwind to the | |
3407 | lexicographically positive solution, that returns the | |
3408 | distance vector (1, -1). */ | |
3409 | if (!lambda_vector_lexico_pos (dist_v, DDR_NB_LOOPS (ddr))) | |
3410 | { | |
3411 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
2f470326 JJ |
3412 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3413 | loop_nest)) | |
3414 | return false; | |
ba42e045 | 3415 | compute_subscript_distance (ddr); |
2f470326 JJ |
3416 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3417 | save_v, &init_b, &index_carry)) | |
3418 | return false; | |
ba42e045 | 3419 | save_dist_v (ddr, save_v); |
71d5b5e1 | 3420 | DDR_REVERSED_P (ddr) = true; |
ba42e045 SP |
3421 | |
3422 | /* In this case there is a dependence forward for all the | |
3423 | outer loops: | |
3424 | ||
3425 | | for (k = 1; k < 100; k++) | |
3426 | | for (i = 1; i < 100; i++) | |
3427 | | for (j = 1; j < 100; j++) | |
3428 | | { | |
3429 | | t = T[j+1][i-1]; // A | |
3430 | | T[j][i] = t + 2; // B | |
3431 | | } | |
3432 | ||
b8698a0f | 3433 | the vectors are: |
ba42e045 SP |
3434 | (0, 1, -1) |
3435 | (1, 1, -1) | |
3436 | (1, -1, 1) | |
3437 | */ | |
3438 | if (DDR_NB_LOOPS (ddr) > 1) | |
3439 | { | |
3440 | add_outer_distances (ddr, save_v, index_carry); | |
3441 | add_outer_distances (ddr, dist_v, index_carry); | |
86df10e3 | 3442 | } |
ba42e045 SP |
3443 | } |
3444 | else | |
3445 | { | |
3446 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3447 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3448 | |
ba42e045 | 3449 | if (DDR_NB_LOOPS (ddr) > 1) |
56cf8686 | 3450 | { |
ba42e045 | 3451 | lambda_vector opposite_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
86df10e3 | 3452 | |
2f470326 JJ |
3453 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), |
3454 | DDR_A (ddr), loop_nest)) | |
3455 | return false; | |
ba42e045 | 3456 | compute_subscript_distance (ddr); |
2f470326 JJ |
3457 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3458 | opposite_v, &init_b, | |
3459 | &index_carry)) | |
3460 | return false; | |
86df10e3 | 3461 | |
2f470326 | 3462 | save_dist_v (ddr, save_v); |
ba42e045 SP |
3463 | add_outer_distances (ddr, dist_v, index_carry); |
3464 | add_outer_distances (ddr, opposite_v, index_carry); | |
56cf8686 | 3465 | } |
2f470326 JJ |
3466 | else |
3467 | save_dist_v (ddr, save_v); | |
56cf8686 SP |
3468 | } |
3469 | } | |
ba42e045 SP |
3470 | else |
3471 | { | |
3472 | /* There is a distance of 1 on all the outer loops: Example: | |
3473 | there is a dependence of distance 1 on loop_1 for the array A. | |
304afda6 | 3474 | |
ba42e045 SP |
3475 | | loop_1 |
3476 | | A[5] = ... | |
3477 | | endloop | |
3478 | */ | |
3479 | add_outer_distances (ddr, dist_v, | |
3480 | lambda_vector_first_nz (dist_v, | |
3481 | DDR_NB_LOOPS (ddr), 0)); | |
3482 | } | |
3483 | ||
3484 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
304afda6 | 3485 | { |
ba42e045 | 3486 | unsigned i; |
304afda6 | 3487 | |
ba42e045 SP |
3488 | fprintf (dump_file, "(build_classic_dist_vector\n"); |
3489 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3490 | { | |
3491 | fprintf (dump_file, " dist_vector = ("); | |
3492 | print_lambda_vector (dump_file, DDR_DIST_VECT (ddr, i), | |
3493 | DDR_NB_LOOPS (ddr)); | |
3494 | fprintf (dump_file, " )\n"); | |
3495 | } | |
3496 | fprintf (dump_file, ")\n"); | |
304afda6 SP |
3497 | } |
3498 | ||
ba42e045 SP |
3499 | return true; |
3500 | } | |
56cf8686 | 3501 | |
ba42e045 SP |
3502 | /* Return the direction for a given distance. |
3503 | FIXME: Computing dir this way is suboptimal, since dir can catch | |
3504 | cases that dist is unable to represent. */ | |
86df10e3 | 3505 | |
ba42e045 SP |
3506 | static inline enum data_dependence_direction |
3507 | dir_from_dist (int dist) | |
3508 | { | |
3509 | if (dist > 0) | |
3510 | return dir_positive; | |
3511 | else if (dist < 0) | |
3512 | return dir_negative; | |
3513 | else | |
3514 | return dir_equal; | |
3515 | } | |
304afda6 | 3516 | |
ba42e045 SP |
3517 | /* Compute the classic per loop direction vector. DDR is the data |
3518 | dependence relation to build a vector from. */ | |
304afda6 | 3519 | |
ba42e045 SP |
3520 | static void |
3521 | build_classic_dir_vector (struct data_dependence_relation *ddr) | |
3522 | { | |
3523 | unsigned i, j; | |
3524 | lambda_vector dist_v; | |
86df10e3 | 3525 | |
9771b263 | 3526 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, dist_v) |
ba42e045 SP |
3527 | { |
3528 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3529 | |
ba42e045 SP |
3530 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) |
3531 | dir_v[j] = dir_from_dist (dist_v[j]); | |
304afda6 | 3532 | |
ba42e045 SP |
3533 | save_dir_v (ddr, dir_v); |
3534 | } | |
56cf8686 SP |
3535 | } |
3536 | ||
ba42e045 SP |
3537 | /* Helper function. Returns true when there is a dependence between |
3538 | data references DRA and DRB. */ | |
0ff4040e | 3539 | |
ba42e045 SP |
3540 | static bool |
3541 | subscript_dependence_tester_1 (struct data_dependence_relation *ddr, | |
3542 | struct data_reference *dra, | |
da9a21f4 SP |
3543 | struct data_reference *drb, |
3544 | struct loop *loop_nest) | |
0ff4040e SP |
3545 | { |
3546 | unsigned int i; | |
0ff4040e | 3547 | tree last_conflicts; |
ebf78a47 | 3548 | struct subscript *subscript; |
9b00587c | 3549 | tree res = NULL_TREE; |
ba42e045 | 3550 | |
9771b263 | 3551 | for (i = 0; DDR_SUBSCRIPTS (ddr).iterate (i, &subscript); i++) |
0ff4040e | 3552 | { |
d93817c4 | 3553 | conflict_function *overlaps_a, *overlaps_b; |
ebf78a47 | 3554 | |
b8698a0f | 3555 | analyze_overlapping_iterations (DR_ACCESS_FN (dra, i), |
0ff4040e | 3556 | DR_ACCESS_FN (drb, i), |
b8698a0f | 3557 | &overlaps_a, &overlaps_b, |
da9a21f4 | 3558 | &last_conflicts, loop_nest); |
ebf78a47 | 3559 | |
9b00587c RG |
3560 | if (SUB_CONFLICTS_IN_A (subscript)) |
3561 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
3562 | if (SUB_CONFLICTS_IN_B (subscript)) | |
3563 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
3564 | ||
3565 | SUB_CONFLICTS_IN_A (subscript) = overlaps_a; | |
3566 | SUB_CONFLICTS_IN_B (subscript) = overlaps_b; | |
3567 | SUB_LAST_CONFLICT (subscript) = last_conflicts; | |
3568 | ||
3569 | /* If there is any undetermined conflict function we have to | |
3570 | give a conservative answer in case we cannot prove that | |
3571 | no dependence exists when analyzing another subscript. */ | |
d93817c4 ZD |
3572 | if (CF_NOT_KNOWN_P (overlaps_a) |
3573 | || CF_NOT_KNOWN_P (overlaps_b)) | |
0ff4040e | 3574 | { |
9b00587c RG |
3575 | res = chrec_dont_know; |
3576 | continue; | |
0ff4040e | 3577 | } |
ebf78a47 | 3578 | |
9b00587c | 3579 | /* When there is a subscript with no dependence we can stop. */ |
d93817c4 ZD |
3580 | else if (CF_NO_DEPENDENCE_P (overlaps_a) |
3581 | || CF_NO_DEPENDENCE_P (overlaps_b)) | |
0ff4040e | 3582 | { |
9b00587c RG |
3583 | res = chrec_known; |
3584 | break; | |
0ff4040e SP |
3585 | } |
3586 | } | |
3587 | ||
9b00587c RG |
3588 | if (res == NULL_TREE) |
3589 | return true; | |
3590 | ||
3591 | if (res == chrec_known) | |
3592 | dependence_stats.num_dependence_independent++; | |
3593 | else | |
3594 | dependence_stats.num_dependence_undetermined++; | |
3595 | finalize_ddr_dependent (ddr, res); | |
3596 | return false; | |
ba42e045 SP |
3597 | } |
3598 | ||
da9a21f4 | 3599 | /* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */ |
ba42e045 SP |
3600 | |
3601 | static void | |
da9a21f4 SP |
3602 | subscript_dependence_tester (struct data_dependence_relation *ddr, |
3603 | struct loop *loop_nest) | |
ba42e045 | 3604 | { |
da9a21f4 | 3605 | if (subscript_dependence_tester_1 (ddr, DDR_A (ddr), DDR_B (ddr), loop_nest)) |
ba42e045 | 3606 | dependence_stats.num_dependence_dependent++; |
0ff4040e | 3607 | |
0ff4040e | 3608 | compute_subscript_distance (ddr); |
da9a21f4 | 3609 | if (build_classic_dist_vector (ddr, loop_nest)) |
ba42e045 | 3610 | build_classic_dir_vector (ddr); |
0ff4040e SP |
3611 | } |
3612 | ||
56cf8686 | 3613 | /* Returns true when all the access functions of A are affine or |
da9a21f4 | 3614 | constant with respect to LOOP_NEST. */ |
56cf8686 | 3615 | |
b8698a0f | 3616 | static bool |
ed7a4b4b KG |
3617 | access_functions_are_affine_or_constant_p (const struct data_reference *a, |
3618 | const struct loop *loop_nest) | |
56cf8686 SP |
3619 | { |
3620 | unsigned int i; | |
9771b263 | 3621 | vec<tree> fns = DR_ACCESS_FNS (a); |
9cbb7989 | 3622 | tree t; |
3d8864c0 | 3623 | |
9771b263 | 3624 | FOR_EACH_VEC_ELT (fns, i, t) |
da9a21f4 SP |
3625 | if (!evolution_function_is_invariant_p (t, loop_nest->num) |
3626 | && !evolution_function_is_affine_multivariate_p (t, loop_nest->num)) | |
56cf8686 | 3627 | return false; |
b8698a0f | 3628 | |
56cf8686 SP |
3629 | return true; |
3630 | } | |
3631 | ||
3d8864c0 SP |
3632 | /* Initializes an equation for an OMEGA problem using the information |
3633 | contained in the ACCESS_FUN. Returns true when the operation | |
3634 | succeeded. | |
3635 | ||
3636 | PB is the omega constraint system. | |
3637 | EQ is the number of the equation to be initialized. | |
3638 | OFFSET is used for shifting the variables names in the constraints: | |
3639 | a constrain is composed of 2 * the number of variables surrounding | |
3640 | dependence accesses. OFFSET is set either to 0 for the first n variables, | |
3641 | then it is set to n. | |
3642 | ACCESS_FUN is expected to be an affine chrec. */ | |
3643 | ||
3644 | static bool | |
b8698a0f L |
3645 | init_omega_eq_with_af (omega_pb pb, unsigned eq, |
3646 | unsigned int offset, tree access_fun, | |
3d8864c0 SP |
3647 | struct data_dependence_relation *ddr) |
3648 | { | |
3649 | switch (TREE_CODE (access_fun)) | |
3650 | { | |
3651 | case POLYNOMIAL_CHREC: | |
3652 | { | |
3653 | tree left = CHREC_LEFT (access_fun); | |
3654 | tree right = CHREC_RIGHT (access_fun); | |
3655 | int var = CHREC_VARIABLE (access_fun); | |
3656 | unsigned var_idx; | |
3657 | ||
3658 | if (TREE_CODE (right) != INTEGER_CST) | |
3659 | return false; | |
3660 | ||
3661 | var_idx = index_in_loop_nest (var, DDR_LOOP_NEST (ddr)); | |
6b6fa4e9 | 3662 | pb->eqs[eq].coef[offset + var_idx + 1] = int_cst_value (right); |
3d8864c0 SP |
3663 | |
3664 | /* Compute the innermost loop index. */ | |
3665 | DDR_INNER_LOOP (ddr) = MAX (DDR_INNER_LOOP (ddr), var_idx); | |
3666 | ||
3667 | if (offset == 0) | |
b8698a0f | 3668 | pb->eqs[eq].coef[var_idx + DDR_NB_LOOPS (ddr) + 1] |
6b6fa4e9 | 3669 | += int_cst_value (right); |
3d8864c0 SP |
3670 | |
3671 | switch (TREE_CODE (left)) | |
3672 | { | |
3673 | case POLYNOMIAL_CHREC: | |
3674 | return init_omega_eq_with_af (pb, eq, offset, left, ddr); | |
3675 | ||
3676 | case INTEGER_CST: | |
6b6fa4e9 | 3677 | pb->eqs[eq].coef[0] += int_cst_value (left); |
3d8864c0 SP |
3678 | return true; |
3679 | ||
3680 | default: | |
3681 | return false; | |
3682 | } | |
3683 | } | |
3684 | ||
3685 | case INTEGER_CST: | |
6b6fa4e9 | 3686 | pb->eqs[eq].coef[0] += int_cst_value (access_fun); |
3d8864c0 SP |
3687 | return true; |
3688 | ||
3689 | default: | |
3690 | return false; | |
3691 | } | |
3692 | } | |
3693 | ||
3694 | /* As explained in the comments preceding init_omega_for_ddr, we have | |
3695 | to set up a system for each loop level, setting outer loops | |
3696 | variation to zero, and current loop variation to positive or zero. | |
3697 | Save each lexico positive distance vector. */ | |
3698 | ||
3699 | static void | |
3700 | omega_extract_distance_vectors (omega_pb pb, | |
3701 | struct data_dependence_relation *ddr) | |
3702 | { | |
3703 | int eq, geq; | |
3704 | unsigned i, j; | |
3705 | struct loop *loopi, *loopj; | |
3706 | enum omega_result res; | |
3707 | ||
3708 | /* Set a new problem for each loop in the nest. The basis is the | |
3709 | problem that we have initialized until now. On top of this we | |
3710 | add new constraints. */ | |
b8698a0f | 3711 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
9771b263 | 3712 | && DDR_LOOP_NEST (ddr).iterate (i, &loopi); i++) |
3d8864c0 SP |
3713 | { |
3714 | int dist = 0; | |
3715 | omega_pb copy = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), | |
3716 | DDR_NB_LOOPS (ddr)); | |
3717 | ||
3718 | omega_copy_problem (copy, pb); | |
3719 | ||
3720 | /* For all the outer loops "loop_j", add "dj = 0". */ | |
9771b263 | 3721 | for (j = 0; j < i && DDR_LOOP_NEST (ddr).iterate (j, &loopj); j++) |
3d8864c0 SP |
3722 | { |
3723 | eq = omega_add_zero_eq (copy, omega_black); | |
3724 | copy->eqs[eq].coef[j + 1] = 1; | |
3725 | } | |
3726 | ||
3727 | /* For "loop_i", add "0 <= di". */ | |
3728 | geq = omega_add_zero_geq (copy, omega_black); | |
3729 | copy->geqs[geq].coef[i + 1] = 1; | |
3730 | ||
3731 | /* Reduce the constraint system, and test that the current | |
3732 | problem is feasible. */ | |
3733 | res = omega_simplify_problem (copy); | |
b8698a0f | 3734 | if (res == omega_false |
3d8864c0 SP |
3735 | || res == omega_unknown |
3736 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3737 | goto next_problem; | |
3738 | ||
3739 | for (eq = 0; eq < copy->num_subs; eq++) | |
3740 | if (copy->subs[eq].key == (int) i + 1) | |
3741 | { | |
3742 | dist = copy->subs[eq].coef[0]; | |
3743 | goto found_dist; | |
3744 | } | |
3745 | ||
3746 | if (dist == 0) | |
3747 | { | |
3748 | /* Reinitialize problem... */ | |
3749 | omega_copy_problem (copy, pb); | |
9771b263 | 3750 | for (j = 0; j < i && DDR_LOOP_NEST (ddr).iterate (j, &loopj); j++) |
3d8864c0 SP |
3751 | { |
3752 | eq = omega_add_zero_eq (copy, omega_black); | |
3753 | copy->eqs[eq].coef[j + 1] = 1; | |
3754 | } | |
3755 | ||
3756 | /* ..., but this time "di = 1". */ | |
3757 | eq = omega_add_zero_eq (copy, omega_black); | |
3758 | copy->eqs[eq].coef[i + 1] = 1; | |
3759 | copy->eqs[eq].coef[0] = -1; | |
3760 | ||
3761 | res = omega_simplify_problem (copy); | |
b8698a0f | 3762 | if (res == omega_false |
3d8864c0 SP |
3763 | || res == omega_unknown |
3764 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3765 | goto next_problem; | |
3766 | ||
3767 | for (eq = 0; eq < copy->num_subs; eq++) | |
3768 | if (copy->subs[eq].key == (int) i + 1) | |
3769 | { | |
3770 | dist = copy->subs[eq].coef[0]; | |
3771 | goto found_dist; | |
3772 | } | |
3773 | } | |
3774 | ||
3775 | found_dist:; | |
3776 | /* Save the lexicographically positive distance vector. */ | |
3777 | if (dist >= 0) | |
3778 | { | |
3779 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3780 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3781 | ||
3782 | dist_v[i] = dist; | |
3783 | ||
3784 | for (eq = 0; eq < copy->num_subs; eq++) | |
3785 | if (copy->subs[eq].key > 0) | |
3786 | { | |
3787 | dist = copy->subs[eq].coef[0]; | |
3788 | dist_v[copy->subs[eq].key - 1] = dist; | |
3789 | } | |
3790 | ||
3791 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3792 | dir_v[j] = dir_from_dist (dist_v[j]); | |
3793 | ||
3794 | save_dist_v (ddr, dist_v); | |
3795 | save_dir_v (ddr, dir_v); | |
3796 | } | |
3797 | ||
3798 | next_problem:; | |
3799 | omega_free_problem (copy); | |
3800 | } | |
3801 | } | |
3802 | ||
3803 | /* This is called for each subscript of a tuple of data references: | |
3804 | insert an equality for representing the conflicts. */ | |
3805 | ||
3806 | static bool | |
3807 | omega_setup_subscript (tree access_fun_a, tree access_fun_b, | |
3808 | struct data_dependence_relation *ddr, | |
3809 | omega_pb pb, bool *maybe_dependent) | |
3810 | { | |
3811 | int eq; | |
33b30201 SP |
3812 | tree type = signed_type_for_types (TREE_TYPE (access_fun_a), |
3813 | TREE_TYPE (access_fun_b)); | |
726a989a RB |
3814 | tree fun_a = chrec_convert (type, access_fun_a, NULL); |
3815 | tree fun_b = chrec_convert (type, access_fun_b, NULL); | |
33b30201 | 3816 | tree difference = chrec_fold_minus (type, fun_a, fun_b); |
5a1f5f9a | 3817 | tree minus_one; |
3d8864c0 SP |
3818 | |
3819 | /* When the fun_a - fun_b is not constant, the dependence is not | |
3820 | captured by the classic distance vector representation. */ | |
3821 | if (TREE_CODE (difference) != INTEGER_CST) | |
3822 | return false; | |
3823 | ||
3824 | /* ZIV test. */ | |
3825 | if (ziv_subscript_p (fun_a, fun_b) && !integer_zerop (difference)) | |
3826 | { | |
3827 | /* There is no dependence. */ | |
3828 | *maybe_dependent = false; | |
3829 | return true; | |
3830 | } | |
3831 | ||
5a1f5f9a SP |
3832 | minus_one = build_int_cst (type, -1); |
3833 | fun_b = chrec_fold_multiply (type, fun_b, minus_one); | |
3d8864c0 SP |
3834 | |
3835 | eq = omega_add_zero_eq (pb, omega_black); | |
3836 | if (!init_omega_eq_with_af (pb, eq, DDR_NB_LOOPS (ddr), fun_a, ddr) | |
3837 | || !init_omega_eq_with_af (pb, eq, 0, fun_b, ddr)) | |
3838 | /* There is probably a dependence, but the system of | |
3839 | constraints cannot be built: answer "don't know". */ | |
3840 | return false; | |
3841 | ||
3842 | /* GCD test. */ | |
3843 | if (DDR_NB_LOOPS (ddr) != 0 && pb->eqs[eq].coef[0] | |
b8698a0f | 3844 | && !int_divides_p (lambda_vector_gcd |
3d8864c0 SP |
3845 | ((lambda_vector) &(pb->eqs[eq].coef[1]), |
3846 | 2 * DDR_NB_LOOPS (ddr)), | |
3847 | pb->eqs[eq].coef[0])) | |
3848 | { | |
3849 | /* There is no dependence. */ | |
3850 | *maybe_dependent = false; | |
3851 | return true; | |
3852 | } | |
3853 | ||
3854 | return true; | |
3855 | } | |
3856 | ||
3857 | /* Helper function, same as init_omega_for_ddr but specialized for | |
3858 | data references A and B. */ | |
3859 | ||
3860 | static bool | |
3861 | init_omega_for_ddr_1 (struct data_reference *dra, struct data_reference *drb, | |
3862 | struct data_dependence_relation *ddr, | |
3863 | omega_pb pb, bool *maybe_dependent) | |
3864 | { | |
3865 | unsigned i; | |
3866 | int ineq; | |
3867 | struct loop *loopi; | |
3868 | unsigned nb_loops = DDR_NB_LOOPS (ddr); | |
3869 | ||
3870 | /* Insert an equality per subscript. */ | |
3871 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3872 | { | |
3873 | if (!omega_setup_subscript (DR_ACCESS_FN (dra, i), DR_ACCESS_FN (drb, i), | |
3874 | ddr, pb, maybe_dependent)) | |
3875 | return false; | |
3876 | else if (*maybe_dependent == false) | |
3877 | { | |
3878 | /* There is no dependence. */ | |
3879 | DDR_ARE_DEPENDENT (ddr) = chrec_known; | |
3880 | return true; | |
3881 | } | |
3882 | } | |
3883 | ||
3884 | /* Insert inequalities: constraints corresponding to the iteration | |
3885 | domain, i.e. the loops surrounding the references "loop_x" and | |
3886 | the distance variables "dx". The layout of the OMEGA | |
3887 | representation is as follows: | |
3888 | - coef[0] is the constant | |
3889 | - coef[1..nb_loops] are the protected variables that will not be | |
3890 | removed by the solver: the "dx" | |
3891 | - coef[nb_loops + 1, 2*nb_loops] are the loop variables: "loop_x". | |
3892 | */ | |
b8698a0f | 3893 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
9771b263 | 3894 | && DDR_LOOP_NEST (ddr).iterate (i, &loopi); i++) |
3d8864c0 | 3895 | { |
652c4c71 | 3896 | HOST_WIDE_INT nbi = max_stmt_executions_int (loopi); |
3d8864c0 SP |
3897 | |
3898 | /* 0 <= loop_x */ | |
3899 | ineq = omega_add_zero_geq (pb, omega_black); | |
3900 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3901 | ||
3902 | /* 0 <= loop_x + dx */ | |
3903 | ineq = omega_add_zero_geq (pb, omega_black); | |
3904 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3905 | pb->geqs[ineq].coef[i + 1] = 1; | |
3906 | ||
3907 | if (nbi != -1) | |
3908 | { | |
3909 | /* loop_x <= nb_iters */ | |
3910 | ineq = omega_add_zero_geq (pb, omega_black); | |
3911 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3912 | pb->geqs[ineq].coef[0] = nbi; | |
3913 | ||
3914 | /* loop_x + dx <= nb_iters */ | |
3915 | ineq = omega_add_zero_geq (pb, omega_black); | |
3916 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3917 | pb->geqs[ineq].coef[i + 1] = -1; | |
3918 | pb->geqs[ineq].coef[0] = nbi; | |
3919 | ||
3920 | /* A step "dx" bigger than nb_iters is not feasible, so | |
3921 | add "0 <= nb_iters + dx", */ | |
3922 | ineq = omega_add_zero_geq (pb, omega_black); | |
3923 | pb->geqs[ineq].coef[i + 1] = 1; | |
3924 | pb->geqs[ineq].coef[0] = nbi; | |
3925 | /* and "dx <= nb_iters". */ | |
3926 | ineq = omega_add_zero_geq (pb, omega_black); | |
3927 | pb->geqs[ineq].coef[i + 1] = -1; | |
3928 | pb->geqs[ineq].coef[0] = nbi; | |
3929 | } | |
3930 | } | |
3931 | ||
3932 | omega_extract_distance_vectors (pb, ddr); | |
3933 | ||
3934 | return true; | |
3935 | } | |
3936 | ||
3937 | /* Sets up the Omega dependence problem for the data dependence | |
3938 | relation DDR. Returns false when the constraint system cannot be | |
3939 | built, ie. when the test answers "don't know". Returns true | |
3940 | otherwise, and when independence has been proved (using one of the | |
3941 | trivial dependence test), set MAYBE_DEPENDENT to false, otherwise | |
3942 | set MAYBE_DEPENDENT to true. | |
3943 | ||
3944 | Example: for setting up the dependence system corresponding to the | |
b8698a0f | 3945 | conflicting accesses |
3d8864c0 SP |
3946 | |
3947 | | loop_i | |
3948 | | loop_j | |
3949 | | A[i, i+1] = ... | |
3950 | | ... A[2*j, 2*(i + j)] | |
3951 | | endloop_j | |
3952 | | endloop_i | |
b8698a0f | 3953 | |
3d8864c0 SP |
3954 | the following constraints come from the iteration domain: |
3955 | ||
3956 | 0 <= i <= Ni | |
3957 | 0 <= i + di <= Ni | |
3958 | 0 <= j <= Nj | |
3959 | 0 <= j + dj <= Nj | |
3960 | ||
3961 | where di, dj are the distance variables. The constraints | |
3962 | representing the conflicting elements are: | |
3963 | ||
3964 | i = 2 * (j + dj) | |
3965 | i + 1 = 2 * (i + di + j + dj) | |
3966 | ||
3967 | For asking that the resulting distance vector (di, dj) be | |
3968 | lexicographically positive, we insert the constraint "di >= 0". If | |
3969 | "di = 0" in the solution, we fix that component to zero, and we | |
3970 | look at the inner loops: we set a new problem where all the outer | |
3971 | loop distances are zero, and fix this inner component to be | |
3972 | positive. When one of the components is positive, we save that | |
3973 | distance, and set a new problem where the distance on this loop is | |
3974 | zero, searching for other distances in the inner loops. Here is | |
3975 | the classic example that illustrates that we have to set for each | |
3976 | inner loop a new problem: | |
3977 | ||
3978 | | loop_1 | |
3979 | | loop_2 | |
3980 | | A[10] | |
3981 | | endloop_2 | |
3982 | | endloop_1 | |
3983 | ||
3984 | we have to save two distances (1, 0) and (0, 1). | |
3985 | ||
3986 | Given two array references, refA and refB, we have to set the | |
3987 | dependence problem twice, refA vs. refB and refB vs. refA, and we | |
3988 | cannot do a single test, as refB might occur before refA in the | |
3989 | inner loops, and the contrary when considering outer loops: ex. | |
3990 | ||
3991 | | loop_0 | |
3992 | | loop_1 | |
3993 | | loop_2 | |
3994 | | T[{1,+,1}_2][{1,+,1}_1] // refA | |
3995 | | T[{2,+,1}_2][{0,+,1}_1] // refB | |
3996 | | endloop_2 | |
3997 | | endloop_1 | |
3998 | | endloop_0 | |
3999 | ||
4000 | refB touches the elements in T before refA, and thus for the same | |
4001 | loop_0 refB precedes refA: ie. the distance vector (0, 1, -1) | |
4002 | but for successive loop_0 iterations, we have (1, -1, 1) | |
4003 | ||
4004 | The Omega solver expects the distance variables ("di" in the | |
4005 | previous example) to come first in the constraint system (as | |
4006 | variables to be protected, or "safe" variables), the constraint | |
4007 | system is built using the following layout: | |
4008 | ||
4009 | "cst | distance vars | index vars". | |
4010 | */ | |
4011 | ||
4012 | static bool | |
4013 | init_omega_for_ddr (struct data_dependence_relation *ddr, | |
4014 | bool *maybe_dependent) | |
4015 | { | |
4016 | omega_pb pb; | |
4017 | bool res = false; | |
4018 | ||
4019 | *maybe_dependent = true; | |
4020 | ||
4021 | if (same_access_functions (ddr)) | |
4022 | { | |
4023 | unsigned j; | |
4024 | lambda_vector dir_v; | |
4025 | ||
4026 | /* Save the 0 vector. */ | |
4027 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
4028 | dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
4029 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
4030 | dir_v[j] = dir_equal; | |
4031 | save_dir_v (ddr, dir_v); | |
4032 | ||
4033 | /* Save the dependences carried by outer loops. */ | |
4034 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4035 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
4036 | maybe_dependent); | |
4037 | omega_free_problem (pb); | |
4038 | return res; | |
4039 | } | |
4040 | ||
4041 | /* Omega expects the protected variables (those that have to be kept | |
4042 | after elimination) to appear first in the constraint system. | |
4043 | These variables are the distance variables. In the following | |
4044 | initialization we declare NB_LOOPS safe variables, and the total | |
4045 | number of variables for the constraint system is 2*NB_LOOPS. */ | |
4046 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4047 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
4048 | maybe_dependent); | |
4049 | omega_free_problem (pb); | |
4050 | ||
4051 | /* Stop computation if not decidable, or no dependence. */ | |
4052 | if (res == false || *maybe_dependent == false) | |
4053 | return res; | |
4054 | ||
4055 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4056 | res = init_omega_for_ddr_1 (DDR_B (ddr), DDR_A (ddr), ddr, pb, | |
4057 | maybe_dependent); | |
4058 | omega_free_problem (pb); | |
4059 | ||
4060 | return res; | |
4061 | } | |
4062 | ||
4063 | /* Return true when DDR contains the same information as that stored | |
4064 | in DIR_VECTS and in DIST_VECTS, return false otherwise. */ | |
4065 | ||
4066 | static bool | |
4067 | ddr_consistent_p (FILE *file, | |
4068 | struct data_dependence_relation *ddr, | |
9771b263 DN |
4069 | vec<lambda_vector> dist_vects, |
4070 | vec<lambda_vector> dir_vects) | |
3d8864c0 SP |
4071 | { |
4072 | unsigned int i, j; | |
4073 | ||
4074 | /* If dump_file is set, output there. */ | |
4075 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4076 | file = dump_file; | |
4077 | ||
9771b263 | 4078 | if (dist_vects.length () != DDR_NUM_DIST_VECTS (ddr)) |
3d8864c0 SP |
4079 | { |
4080 | lambda_vector b_dist_v; | |
4081 | fprintf (file, "\n(Number of distance vectors differ: Banerjee has %d, Omega has %d.\n", | |
9771b263 | 4082 | dist_vects.length (), |
3d8864c0 SP |
4083 | DDR_NUM_DIST_VECTS (ddr)); |
4084 | ||
4085 | fprintf (file, "Banerjee dist vectors:\n"); | |
9771b263 | 4086 | FOR_EACH_VEC_ELT (dist_vects, i, b_dist_v) |
3d8864c0 SP |
4087 | print_lambda_vector (file, b_dist_v, DDR_NB_LOOPS (ddr)); |
4088 | ||
4089 | fprintf (file, "Omega dist vectors:\n"); | |
4090 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
4091 | print_lambda_vector (file, DDR_DIST_VECT (ddr, i), DDR_NB_LOOPS (ddr)); | |
4092 | ||
4093 | fprintf (file, "data dependence relation:\n"); | |
4094 | dump_data_dependence_relation (file, ddr); | |
4095 | ||
4096 | fprintf (file, ")\n"); | |
4097 | return false; | |
4098 | } | |
4099 | ||
9771b263 | 4100 | if (dir_vects.length () != DDR_NUM_DIR_VECTS (ddr)) |
3d8864c0 SP |
4101 | { |
4102 | fprintf (file, "\n(Number of direction vectors differ: Banerjee has %d, Omega has %d.)\n", | |
9771b263 | 4103 | dir_vects.length (), |
3d8864c0 SP |
4104 | DDR_NUM_DIR_VECTS (ddr)); |
4105 | return false; | |
4106 | } | |
4107 | ||
4108 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
4109 | { | |
4110 | lambda_vector a_dist_v; | |
4111 | lambda_vector b_dist_v = DDR_DIST_VECT (ddr, i); | |
4112 | ||
4113 | /* Distance vectors are not ordered in the same way in the DDR | |
4114 | and in the DIST_VECTS: search for a matching vector. */ | |
9771b263 | 4115 | FOR_EACH_VEC_ELT (dist_vects, j, a_dist_v) |
3d8864c0 SP |
4116 | if (lambda_vector_equal (a_dist_v, b_dist_v, DDR_NB_LOOPS (ddr))) |
4117 | break; | |
4118 | ||
9771b263 | 4119 | if (j == dist_vects.length ()) |
3d8864c0 SP |
4120 | { |
4121 | fprintf (file, "\n(Dist vectors from the first dependence analyzer:\n"); | |
4122 | print_dist_vectors (file, dist_vects, DDR_NB_LOOPS (ddr)); | |
4123 | fprintf (file, "not found in Omega dist vectors:\n"); | |
4124 | print_dist_vectors (file, DDR_DIST_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4125 | fprintf (file, "data dependence relation:\n"); | |
4126 | dump_data_dependence_relation (file, ddr); | |
4127 | fprintf (file, ")\n"); | |
4128 | } | |
4129 | } | |
4130 | ||
4131 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
4132 | { | |
4133 | lambda_vector a_dir_v; | |
4134 | lambda_vector b_dir_v = DDR_DIR_VECT (ddr, i); | |
4135 | ||
4136 | /* Direction vectors are not ordered in the same way in the DDR | |
4137 | and in the DIR_VECTS: search for a matching vector. */ | |
9771b263 | 4138 | FOR_EACH_VEC_ELT (dir_vects, j, a_dir_v) |
3d8864c0 SP |
4139 | if (lambda_vector_equal (a_dir_v, b_dir_v, DDR_NB_LOOPS (ddr))) |
4140 | break; | |
4141 | ||
9771b263 | 4142 | if (j == dist_vects.length ()) |
3d8864c0 SP |
4143 | { |
4144 | fprintf (file, "\n(Dir vectors from the first dependence analyzer:\n"); | |
4145 | print_dir_vectors (file, dir_vects, DDR_NB_LOOPS (ddr)); | |
4146 | fprintf (file, "not found in Omega dir vectors:\n"); | |
4147 | print_dir_vectors (file, DDR_DIR_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4148 | fprintf (file, "data dependence relation:\n"); | |
4149 | dump_data_dependence_relation (file, ddr); | |
4150 | fprintf (file, ")\n"); | |
4151 | } | |
4152 | } | |
4153 | ||
b8698a0f | 4154 | return true; |
3d8864c0 SP |
4155 | } |
4156 | ||
da9a21f4 SP |
4157 | /* This computes the affine dependence relation between A and B with |
4158 | respect to LOOP_NEST. CHREC_KNOWN is used for representing the | |
4159 | independence between two accesses, while CHREC_DONT_KNOW is used | |
4160 | for representing the unknown relation. | |
b8698a0f | 4161 | |
56cf8686 SP |
4162 | Note that it is possible to stop the computation of the dependence |
4163 | relation the first time we detect a CHREC_KNOWN element for a given | |
4164 | subscript. */ | |
4165 | ||
f20132e7 | 4166 | void |
da9a21f4 SP |
4167 | compute_affine_dependence (struct data_dependence_relation *ddr, |
4168 | struct loop *loop_nest) | |
56cf8686 SP |
4169 | { |
4170 | struct data_reference *dra = DDR_A (ddr); | |
4171 | struct data_reference *drb = DDR_B (ddr); | |
b8698a0f | 4172 | |
56cf8686 SP |
4173 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4174 | { | |
36d59cf7 | 4175 | fprintf (dump_file, "(compute_affine_dependence\n"); |
c4ddde1b RG |
4176 | fprintf (dump_file, " stmt_a: "); |
4177 | print_gimple_stmt (dump_file, DR_STMT (dra), 0, TDF_SLIM); | |
4178 | fprintf (dump_file, " stmt_b: "); | |
4179 | print_gimple_stmt (dump_file, DR_STMT (drb), 0, TDF_SLIM); | |
56cf8686 | 4180 | } |
0ff4040e | 4181 | |
56cf8686 | 4182 | /* Analyze only when the dependence relation is not yet known. */ |
1a4571cb | 4183 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
56cf8686 | 4184 | { |
0ff4040e SP |
4185 | dependence_stats.num_dependence_tests++; |
4186 | ||
da9a21f4 SP |
4187 | if (access_functions_are_affine_or_constant_p (dra, loop_nest) |
4188 | && access_functions_are_affine_or_constant_p (drb, loop_nest)) | |
3d8864c0 | 4189 | { |
bcf1ef00 RB |
4190 | subscript_dependence_tester (ddr, loop_nest); |
4191 | ||
3d8864c0 SP |
4192 | if (flag_check_data_deps) |
4193 | { | |
bcf1ef00 | 4194 | /* Dump the dependences from the first algorithm. */ |
3d8864c0 SP |
4195 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4196 | { | |
4197 | fprintf (dump_file, "\n\nBanerjee Analyzer\n"); | |
4198 | dump_data_dependence_relation (dump_file, ddr); | |
4199 | } | |
4200 | ||
4201 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
4202 | { | |
4203 | bool maybe_dependent; | |
9771b263 | 4204 | vec<lambda_vector> dir_vects, dist_vects; |
3d8864c0 SP |
4205 | |
4206 | /* Save the result of the first DD analyzer. */ | |
4207 | dist_vects = DDR_DIST_VECTS (ddr); | |
4208 | dir_vects = DDR_DIR_VECTS (ddr); | |
4209 | ||
4210 | /* Reset the information. */ | |
9771b263 DN |
4211 | DDR_DIST_VECTS (ddr).create (0); |
4212 | DDR_DIR_VECTS (ddr).create (0); | |
3d8864c0 SP |
4213 | |
4214 | /* Compute the same information using Omega. */ | |
4215 | if (!init_omega_for_ddr (ddr, &maybe_dependent)) | |
4216 | goto csys_dont_know; | |
4217 | ||
4218 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4219 | { | |
4220 | fprintf (dump_file, "Omega Analyzer\n"); | |
4221 | dump_data_dependence_relation (dump_file, ddr); | |
4222 | } | |
4223 | ||
4224 | /* Check that we get the same information. */ | |
4225 | if (maybe_dependent) | |
4226 | gcc_assert (ddr_consistent_p (stderr, ddr, dist_vects, | |
4227 | dir_vects)); | |
4228 | } | |
4229 | } | |
3d8864c0 | 4230 | } |
b8698a0f | 4231 | |
56cf8686 SP |
4232 | /* As a last case, if the dependence cannot be determined, or if |
4233 | the dependence is considered too difficult to determine, answer | |
4234 | "don't know". */ | |
4235 | else | |
0ff4040e | 4236 | { |
3d8864c0 | 4237 | csys_dont_know:; |
0ff4040e SP |
4238 | dependence_stats.num_dependence_undetermined++; |
4239 | ||
4240 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4241 | { | |
4242 | fprintf (dump_file, "Data ref a:\n"); | |
4243 | dump_data_reference (dump_file, dra); | |
4244 | fprintf (dump_file, "Data ref b:\n"); | |
4245 | dump_data_reference (dump_file, drb); | |
4246 | fprintf (dump_file, "affine dependence test not usable: access function not affine or constant.\n"); | |
4247 | } | |
4248 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
4249 | } | |
56cf8686 | 4250 | } |
b8698a0f | 4251 | |
56cf8686 | 4252 | if (dump_file && (dump_flags & TDF_DETAILS)) |
c4ddde1b RG |
4253 | { |
4254 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) | |
4255 | fprintf (dump_file, ") -> no dependence\n"); | |
4256 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) | |
4257 | fprintf (dump_file, ") -> dependence analysis failed\n"); | |
4258 | else | |
4259 | fprintf (dump_file, ")\n"); | |
4260 | } | |
56cf8686 SP |
4261 | } |
4262 | ||
ba42e045 SP |
4263 | /* Compute in DEPENDENCE_RELATIONS the data dependence graph for all |
4264 | the data references in DATAREFS, in the LOOP_NEST. When | |
ebf78a47 | 4265 | COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self |
3881dee9 AB |
4266 | relations. Return true when successful, i.e. data references number |
4267 | is small enough to be handled. */ | |
56cf8686 | 4268 | |
3881dee9 | 4269 | bool |
9771b263 DN |
4270 | compute_all_dependences (vec<data_reference_p> datarefs, |
4271 | vec<ddr_p> *dependence_relations, | |
4272 | vec<loop_p> loop_nest, | |
ebf78a47 | 4273 | bool compute_self_and_rr) |
56cf8686 | 4274 | { |
ebf78a47 SP |
4275 | struct data_dependence_relation *ddr; |
4276 | struct data_reference *a, *b; | |
4277 | unsigned int i, j; | |
56cf8686 | 4278 | |
9771b263 | 4279 | if ((int) datarefs.length () |
3881dee9 AB |
4280 | > PARAM_VALUE (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS)) |
4281 | { | |
4282 | struct data_dependence_relation *ddr; | |
4283 | ||
4284 | /* Insert a single relation into dependence_relations: | |
4285 | chrec_dont_know. */ | |
4286 | ddr = initialize_data_dependence_relation (NULL, NULL, loop_nest); | |
9771b263 | 4287 | dependence_relations->safe_push (ddr); |
3881dee9 AB |
4288 | return false; |
4289 | } | |
4290 | ||
9771b263 DN |
4291 | FOR_EACH_VEC_ELT (datarefs, i, a) |
4292 | for (j = i + 1; datarefs.iterate (j, &b); j++) | |
b0af49c4 | 4293 | if (DR_IS_WRITE (a) || DR_IS_WRITE (b) || compute_self_and_rr) |
ebf78a47 SP |
4294 | { |
4295 | ddr = initialize_data_dependence_relation (a, b, loop_nest); | |
9771b263 DN |
4296 | dependence_relations->safe_push (ddr); |
4297 | if (loop_nest.exists ()) | |
4298 | compute_affine_dependence (ddr, loop_nest[0]); | |
ebf78a47 | 4299 | } |
789246d7 | 4300 | |
ebf78a47 | 4301 | if (compute_self_and_rr) |
9771b263 | 4302 | FOR_EACH_VEC_ELT (datarefs, i, a) |
56cf8686 | 4303 | { |
ebf78a47 | 4304 | ddr = initialize_data_dependence_relation (a, a, loop_nest); |
9771b263 DN |
4305 | dependence_relations->safe_push (ddr); |
4306 | if (loop_nest.exists ()) | |
4307 | compute_affine_dependence (ddr, loop_nest[0]); | |
56cf8686 | 4308 | } |
3881dee9 AB |
4309 | |
4310 | return true; | |
56cf8686 SP |
4311 | } |
4312 | ||
aeb83f09 RG |
4313 | /* Describes a location of a memory reference. */ |
4314 | ||
4315 | typedef struct data_ref_loc_d | |
4316 | { | |
fcac74a1 RB |
4317 | /* Position of the memory reference. */ |
4318 | tree *pos; | |
aeb83f09 | 4319 | |
fcac74a1 RB |
4320 | /* True if the memory reference is read. */ |
4321 | bool is_read; | |
aeb83f09 RG |
4322 | } data_ref_loc; |
4323 | ||
aeb83f09 | 4324 | |
946e1bc7 ZD |
4325 | /* Stores the locations of memory references in STMT to REFERENCES. Returns |
4326 | true if STMT clobbers memory, false otherwise. */ | |
4327 | ||
aeb83f09 | 4328 | static bool |
ff4c81cc | 4329 | get_references_in_stmt (gimple stmt, vec<data_ref_loc, va_heap> *references) |
946e1bc7 ZD |
4330 | { |
4331 | bool clobbers_memory = false; | |
f32682ca | 4332 | data_ref_loc ref; |
726a989a RB |
4333 | tree *op0, *op1; |
4334 | enum gimple_code stmt_code = gimple_code (stmt); | |
946e1bc7 | 4335 | |
946e1bc7 | 4336 | /* ASM_EXPR and CALL_EXPR may embed arbitrary side effects. |
f2ea3c15 RG |
4337 | As we cannot model data-references to not spelled out |
4338 | accesses give up if they may occur. */ | |
74bf76ed JJ |
4339 | if (stmt_code == GIMPLE_CALL |
4340 | && !(gimple_call_flags (stmt) & ECF_CONST)) | |
4341 | { | |
4342 | /* Allow IFN_GOMP_SIMD_LANE in their own loops. */ | |
4343 | if (gimple_call_internal_p (stmt) | |
4344 | && gimple_call_internal_fn (stmt) == IFN_GOMP_SIMD_LANE) | |
4345 | { | |
4346 | struct loop *loop = gimple_bb (stmt)->loop_father; | |
4347 | tree uid = gimple_call_arg (stmt, 0); | |
4348 | gcc_assert (TREE_CODE (uid) == SSA_NAME); | |
4349 | if (loop == NULL | |
4350 | || loop->simduid != SSA_NAME_VAR (uid)) | |
4351 | clobbers_memory = true; | |
4352 | } | |
4353 | else | |
4354 | clobbers_memory = true; | |
4355 | } | |
4356 | else if (stmt_code == GIMPLE_ASM | |
4357 | && (gimple_asm_volatile_p (stmt) || gimple_vuse (stmt))) | |
946e1bc7 ZD |
4358 | clobbers_memory = true; |
4359 | ||
5006671f | 4360 | if (!gimple_vuse (stmt)) |
946e1bc7 ZD |
4361 | return clobbers_memory; |
4362 | ||
726a989a | 4363 | if (stmt_code == GIMPLE_ASSIGN) |
946e1bc7 | 4364 | { |
c8ae0bec | 4365 | tree base; |
726a989a RB |
4366 | op0 = gimple_assign_lhs_ptr (stmt); |
4367 | op1 = gimple_assign_rhs1_ptr (stmt); | |
b8698a0f | 4368 | |
946e1bc7 | 4369 | if (DECL_P (*op1) |
c8ae0bec RG |
4370 | || (REFERENCE_CLASS_P (*op1) |
4371 | && (base = get_base_address (*op1)) | |
4372 | && TREE_CODE (base) != SSA_NAME)) | |
946e1bc7 | 4373 | { |
f32682ca DN |
4374 | ref.pos = op1; |
4375 | ref.is_read = true; | |
9771b263 | 4376 | references->safe_push (ref); |
946e1bc7 | 4377 | } |
946e1bc7 | 4378 | } |
726a989a | 4379 | else if (stmt_code == GIMPLE_CALL) |
946e1bc7 | 4380 | { |
1b14d815 | 4381 | unsigned i, n; |
ac84e05e | 4382 | |
1b14d815 RS |
4383 | op0 = gimple_call_lhs_ptr (stmt); |
4384 | n = gimple_call_num_args (stmt); | |
ac84e05e | 4385 | for (i = 0; i < n; i++) |
946e1bc7 | 4386 | { |
1b14d815 | 4387 | op1 = gimple_call_arg_ptr (stmt, i); |
ac84e05e | 4388 | |
1b14d815 RS |
4389 | if (DECL_P (*op1) |
4390 | || (REFERENCE_CLASS_P (*op1) && get_base_address (*op1))) | |
946e1bc7 | 4391 | { |
f32682ca DN |
4392 | ref.pos = op1; |
4393 | ref.is_read = true; | |
9771b263 | 4394 | references->safe_push (ref); |
946e1bc7 ZD |
4395 | } |
4396 | } | |
4397 | } | |
1b14d815 RS |
4398 | else |
4399 | return clobbers_memory; | |
946e1bc7 | 4400 | |
1b14d815 RS |
4401 | if (*op0 |
4402 | && (DECL_P (*op0) | |
4403 | || (REFERENCE_CLASS_P (*op0) && get_base_address (*op0)))) | |
4404 | { | |
f32682ca DN |
4405 | ref.pos = op0; |
4406 | ref.is_read = false; | |
9771b263 | 4407 | references->safe_push (ref); |
1b14d815 | 4408 | } |
946e1bc7 ZD |
4409 | return clobbers_memory; |
4410 | } | |
4411 | ||
4412 | /* Stores the data references in STMT to DATAREFS. If there is an unanalyzable | |
3cb960c7 | 4413 | reference, returns false, otherwise returns true. NEST is the outermost |
f8bf9252 | 4414 | loop of the loop nest in which the references should be analyzed. */ |
946e1bc7 | 4415 | |
f8bf9252 | 4416 | bool |
726a989a | 4417 | find_data_references_in_stmt (struct loop *nest, gimple stmt, |
9771b263 | 4418 | vec<data_reference_p> *datarefs) |
946e1bc7 ZD |
4419 | { |
4420 | unsigned i; | |
ff4c81cc | 4421 | stack_vec<data_ref_loc, 2> references; |
946e1bc7 ZD |
4422 | data_ref_loc *ref; |
4423 | bool ret = true; | |
4424 | data_reference_p dr; | |
4425 | ||
4426 | if (get_references_in_stmt (stmt, &references)) | |
ff4c81cc | 4427 | return false; |
946e1bc7 | 4428 | |
9771b263 | 4429 | FOR_EACH_VEC_ELT (references, i, ref) |
946e1bc7 | 4430 | { |
5c640e29 SP |
4431 | dr = create_data_ref (nest, loop_containing_stmt (stmt), |
4432 | *ref->pos, stmt, ref->is_read); | |
bbc8a8dc | 4433 | gcc_assert (dr != NULL); |
9771b263 | 4434 | datarefs->safe_push (dr); |
946e1bc7 | 4435 | } |
9771b263 | 4436 | references.release (); |
946e1bc7 ZD |
4437 | return ret; |
4438 | } | |
4439 | ||
5c640e29 SP |
4440 | /* Stores the data references in STMT to DATAREFS. If there is an |
4441 | unanalyzable reference, returns false, otherwise returns true. | |
4442 | NEST is the outermost loop of the loop nest in which the references | |
4443 | should be instantiated, LOOP is the loop in which the references | |
4444 | should be analyzed. */ | |
ed91d661 SP |
4445 | |
4446 | bool | |
5c640e29 | 4447 | graphite_find_data_references_in_stmt (loop_p nest, loop_p loop, gimple stmt, |
9771b263 | 4448 | vec<data_reference_p> *datarefs) |
ed91d661 SP |
4449 | { |
4450 | unsigned i; | |
ff4c81cc | 4451 | stack_vec<data_ref_loc, 2> references; |
ed91d661 SP |
4452 | data_ref_loc *ref; |
4453 | bool ret = true; | |
4454 | data_reference_p dr; | |
4455 | ||
4456 | if (get_references_in_stmt (stmt, &references)) | |
ff4c81cc | 4457 | return false; |
ed91d661 | 4458 | |
9771b263 | 4459 | FOR_EACH_VEC_ELT (references, i, ref) |
ed91d661 | 4460 | { |
5c640e29 | 4461 | dr = create_data_ref (nest, loop, *ref->pos, stmt, ref->is_read); |
ed91d661 | 4462 | gcc_assert (dr != NULL); |
9771b263 | 4463 | datarefs->safe_push (dr); |
ed91d661 SP |
4464 | } |
4465 | ||
9771b263 | 4466 | references.release (); |
ed91d661 SP |
4467 | return ret; |
4468 | } | |
4469 | ||
a70d6342 IR |
4470 | /* Search the data references in LOOP, and record the information into |
4471 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4472 | difficult case, returns NULL_TREE otherwise. */ | |
4473 | ||
bfe068c3 | 4474 | tree |
a70d6342 | 4475 | find_data_references_in_bb (struct loop *loop, basic_block bb, |
9771b263 | 4476 | vec<data_reference_p> *datarefs) |
a70d6342 IR |
4477 | { |
4478 | gimple_stmt_iterator bsi; | |
4479 | ||
4480 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
4481 | { | |
4482 | gimple stmt = gsi_stmt (bsi); | |
4483 | ||
4484 | if (!find_data_references_in_stmt (loop, stmt, datarefs)) | |
4485 | { | |
4486 | struct data_reference *res; | |
4487 | res = XCNEW (struct data_reference); | |
9771b263 | 4488 | datarefs->safe_push (res); |
a70d6342 IR |
4489 | |
4490 | return chrec_dont_know; | |
4491 | } | |
4492 | } | |
4493 | ||
4494 | return NULL_TREE; | |
4495 | } | |
4496 | ||
56cf8686 SP |
4497 | /* Search the data references in LOOP, and record the information into |
4498 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4499 | difficult case, returns NULL_TREE otherwise. | |
3cb960c7 | 4500 | |
464f49d8 DB |
4501 | TODO: This function should be made smarter so that it can handle address |
4502 | arithmetic as if they were array accesses, etc. */ | |
56cf8686 | 4503 | |
fcac74a1 | 4504 | tree |
ebf78a47 | 4505 | find_data_references_in_loop (struct loop *loop, |
9771b263 | 4506 | vec<data_reference_p> *datarefs) |
56cf8686 | 4507 | { |
ccbdbf0a JL |
4508 | basic_block bb, *bbs; |
4509 | unsigned int i; | |
86df10e3 | 4510 | |
bbc8a8dc | 4511 | bbs = get_loop_body_in_dom_order (loop); |
ccbdbf0a JL |
4512 | |
4513 | for (i = 0; i < loop->num_nodes; i++) | |
56cf8686 | 4514 | { |
ccbdbf0a JL |
4515 | bb = bbs[i]; |
4516 | ||
a70d6342 IR |
4517 | if (find_data_references_in_bb (loop, bb, datarefs) == chrec_dont_know) |
4518 | { | |
4519 | free (bbs); | |
4520 | return chrec_dont_know; | |
4521 | } | |
56cf8686 | 4522 | } |
ccbdbf0a JL |
4523 | free (bbs); |
4524 | ||
4aad410d | 4525 | return NULL_TREE; |
56cf8686 SP |
4526 | } |
4527 | ||
ba42e045 SP |
4528 | /* Recursive helper function. */ |
4529 | ||
4530 | static bool | |
9771b263 | 4531 | find_loop_nest_1 (struct loop *loop, vec<loop_p> *loop_nest) |
ba42e045 SP |
4532 | { |
4533 | /* Inner loops of the nest should not contain siblings. Example: | |
4534 | when there are two consecutive loops, | |
4535 | ||
4536 | | loop_0 | |
4537 | | loop_1 | |
4538 | | A[{0, +, 1}_1] | |
4539 | | endloop_1 | |
4540 | | loop_2 | |
4541 | | A[{0, +, 1}_2] | |
4542 | | endloop_2 | |
4543 | | endloop_0 | |
4544 | ||
4545 | the dependence relation cannot be captured by the distance | |
4546 | abstraction. */ | |
4547 | if (loop->next) | |
4548 | return false; | |
56cf8686 | 4549 | |
9771b263 | 4550 | loop_nest->safe_push (loop); |
ba42e045 SP |
4551 | if (loop->inner) |
4552 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4553 | return true; | |
4554 | } | |
4555 | ||
4556 | /* Return false when the LOOP is not well nested. Otherwise return | |
4557 | true and insert in LOOP_NEST the loops of the nest. LOOP_NEST will | |
4558 | contain the loops from the outermost to the innermost, as they will | |
4559 | appear in the classic distance vector. */ | |
4560 | ||
5417e022 | 4561 | bool |
9771b263 | 4562 | find_loop_nest (struct loop *loop, vec<loop_p> *loop_nest) |
ba42e045 | 4563 | { |
9771b263 | 4564 | loop_nest->safe_push (loop); |
ba42e045 SP |
4565 | if (loop->inner) |
4566 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4567 | return true; | |
4568 | } | |
56cf8686 | 4569 | |
9f275479 JS |
4570 | /* Returns true when the data dependences have been computed, false otherwise. |
4571 | Given a loop nest LOOP, the following vectors are returned: | |
b8698a0f L |
4572 | DATAREFS is initialized to all the array elements contained in this loop, |
4573 | DEPENDENCE_RELATIONS contains the relations between the data references. | |
4574 | Compute read-read and self relations if | |
86a07404 | 4575 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ |
56cf8686 | 4576 | |
9f275479 | 4577 | bool |
b8698a0f | 4578 | compute_data_dependences_for_loop (struct loop *loop, |
86a07404 | 4579 | bool compute_self_and_read_read_dependences, |
9771b263 DN |
4580 | vec<loop_p> *loop_nest, |
4581 | vec<data_reference_p> *datarefs, | |
4582 | vec<ddr_p> *dependence_relations) | |
56cf8686 | 4583 | { |
9f275479 | 4584 | bool res = true; |
86a07404 | 4585 | |
0ff4040e | 4586 | memset (&dependence_stats, 0, sizeof (dependence_stats)); |
56cf8686 | 4587 | |
b8698a0f | 4588 | /* If the loop nest is not well formed, or one of the data references |
ba42e045 SP |
4589 | is not computable, give up without spending time to compute other |
4590 | dependences. */ | |
3cb960c7 | 4591 | if (!loop |
01be8516 | 4592 | || !find_loop_nest (loop, loop_nest) |
3881dee9 AB |
4593 | || find_data_references_in_loop (loop, datarefs) == chrec_dont_know |
4594 | || !compute_all_dependences (*datarefs, dependence_relations, *loop_nest, | |
4595 | compute_self_and_read_read_dependences)) | |
4596 | res = false; | |
0ff4040e SP |
4597 | |
4598 | if (dump_file && (dump_flags & TDF_STATS)) | |
56cf8686 | 4599 | { |
0ff4040e SP |
4600 | fprintf (dump_file, "Dependence tester statistics:\n"); |
4601 | ||
b8698a0f | 4602 | fprintf (dump_file, "Number of dependence tests: %d\n", |
0ff4040e | 4603 | dependence_stats.num_dependence_tests); |
b8698a0f | 4604 | fprintf (dump_file, "Number of dependence tests classified dependent: %d\n", |
0ff4040e | 4605 | dependence_stats.num_dependence_dependent); |
b8698a0f | 4606 | fprintf (dump_file, "Number of dependence tests classified independent: %d\n", |
0ff4040e | 4607 | dependence_stats.num_dependence_independent); |
b8698a0f | 4608 | fprintf (dump_file, "Number of undetermined dependence tests: %d\n", |
0ff4040e SP |
4609 | dependence_stats.num_dependence_undetermined); |
4610 | ||
b8698a0f | 4611 | fprintf (dump_file, "Number of subscript tests: %d\n", |
0ff4040e | 4612 | dependence_stats.num_subscript_tests); |
b8698a0f | 4613 | fprintf (dump_file, "Number of undetermined subscript tests: %d\n", |
0ff4040e | 4614 | dependence_stats.num_subscript_undetermined); |
b8698a0f | 4615 | fprintf (dump_file, "Number of same subscript function: %d\n", |
0ff4040e SP |
4616 | dependence_stats.num_same_subscript_function); |
4617 | ||
4618 | fprintf (dump_file, "Number of ziv tests: %d\n", | |
4619 | dependence_stats.num_ziv); | |
4620 | fprintf (dump_file, "Number of ziv tests returning dependent: %d\n", | |
4621 | dependence_stats.num_ziv_dependent); | |
4622 | fprintf (dump_file, "Number of ziv tests returning independent: %d\n", | |
4623 | dependence_stats.num_ziv_independent); | |
4624 | fprintf (dump_file, "Number of ziv tests unimplemented: %d\n", | |
b8698a0f | 4625 | dependence_stats.num_ziv_unimplemented); |
0ff4040e | 4626 | |
b8698a0f | 4627 | fprintf (dump_file, "Number of siv tests: %d\n", |
0ff4040e SP |
4628 | dependence_stats.num_siv); |
4629 | fprintf (dump_file, "Number of siv tests returning dependent: %d\n", | |
4630 | dependence_stats.num_siv_dependent); | |
4631 | fprintf (dump_file, "Number of siv tests returning independent: %d\n", | |
4632 | dependence_stats.num_siv_independent); | |
4633 | fprintf (dump_file, "Number of siv tests unimplemented: %d\n", | |
4634 | dependence_stats.num_siv_unimplemented); | |
4635 | ||
b8698a0f | 4636 | fprintf (dump_file, "Number of miv tests: %d\n", |
0ff4040e SP |
4637 | dependence_stats.num_miv); |
4638 | fprintf (dump_file, "Number of miv tests returning dependent: %d\n", | |
4639 | dependence_stats.num_miv_dependent); | |
4640 | fprintf (dump_file, "Number of miv tests returning independent: %d\n", | |
4641 | dependence_stats.num_miv_independent); | |
4642 | fprintf (dump_file, "Number of miv tests unimplemented: %d\n", | |
4643 | dependence_stats.num_miv_unimplemented); | |
9f275479 JS |
4644 | } |
4645 | ||
4646 | return res; | |
56cf8686 SP |
4647 | } |
4648 | ||
b8698a0f | 4649 | /* Returns true when the data dependences for the basic block BB have been |
a70d6342 | 4650 | computed, false otherwise. |
b8698a0f | 4651 | DATAREFS is initialized to all the array elements contained in this basic |
a70d6342 IR |
4652 | block, DEPENDENCE_RELATIONS contains the relations between the data |
4653 | references. Compute read-read and self relations if | |
4654 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ | |
4655 | bool | |
4656 | compute_data_dependences_for_bb (basic_block bb, | |
4657 | bool compute_self_and_read_read_dependences, | |
9771b263 DN |
4658 | vec<data_reference_p> *datarefs, |
4659 | vec<ddr_p> *dependence_relations) | |
a70d6342 IR |
4660 | { |
4661 | if (find_data_references_in_bb (NULL, bb, datarefs) == chrec_dont_know) | |
4662 | return false; | |
4663 | ||
6e1aa848 | 4664 | return compute_all_dependences (*datarefs, dependence_relations, vNULL, |
3881dee9 | 4665 | compute_self_and_read_read_dependences); |
a70d6342 IR |
4666 | } |
4667 | ||
56cf8686 | 4668 | /* Entry point (for testing only). Analyze all the data references |
3d8864c0 | 4669 | and the dependence relations in LOOP. |
56cf8686 | 4670 | |
b8698a0f L |
4671 | The data references are computed first. |
4672 | ||
56cf8686 SP |
4673 | A relation on these nodes is represented by a complete graph. Some |
4674 | of the relations could be of no interest, thus the relations can be | |
4675 | computed on demand. | |
b8698a0f | 4676 | |
56cf8686 SP |
4677 | In the following function we compute all the relations. This is |
4678 | just a first implementation that is here for: | |
b8698a0f | 4679 | - for showing how to ask for the dependence relations, |
56cf8686 SP |
4680 | - for the debugging the whole dependence graph, |
4681 | - for the dejagnu testcases and maintenance. | |
b8698a0f | 4682 | |
56cf8686 SP |
4683 | It is possible to ask only for a part of the graph, avoiding to |
4684 | compute the whole dependence graph. The computed dependences are | |
4685 | stored in a knowledge base (KB) such that later queries don't | |
4686 | recompute the same information. The implementation of this KB is | |
4687 | transparent to the optimizer, and thus the KB can be changed with a | |
4688 | more efficient implementation, or the KB could be disabled. */ | |
b8698a0f | 4689 | static void |
3d8864c0 | 4690 | analyze_all_data_dependences (struct loop *loop) |
56cf8686 SP |
4691 | { |
4692 | unsigned int i; | |
56cf8686 | 4693 | int nb_data_refs = 10; |
9771b263 DN |
4694 | vec<data_reference_p> datarefs; |
4695 | datarefs.create (nb_data_refs); | |
4696 | vec<ddr_p> dependence_relations; | |
4697 | dependence_relations.create (nb_data_refs * nb_data_refs); | |
4698 | vec<loop_p> loop_nest; | |
4699 | loop_nest.create (3); | |
56cf8686 SP |
4700 | |
4701 | /* Compute DDs on the whole function. */ | |
01be8516 | 4702 | compute_data_dependences_for_loop (loop, false, &loop_nest, &datarefs, |
3d8864c0 | 4703 | &dependence_relations); |
56cf8686 SP |
4704 | |
4705 | if (dump_file) | |
4706 | { | |
4707 | dump_data_dependence_relations (dump_file, dependence_relations); | |
4708 | fprintf (dump_file, "\n\n"); | |
56cf8686 | 4709 | |
86df10e3 SP |
4710 | if (dump_flags & TDF_DETAILS) |
4711 | dump_dist_dir_vectors (dump_file, dependence_relations); | |
56cf8686 | 4712 | |
86df10e3 | 4713 | if (dump_flags & TDF_STATS) |
56cf8686 | 4714 | { |
86df10e3 SP |
4715 | unsigned nb_top_relations = 0; |
4716 | unsigned nb_bot_relations = 0; | |
86df10e3 | 4717 | unsigned nb_chrec_relations = 0; |
ebf78a47 | 4718 | struct data_dependence_relation *ddr; |
86df10e3 | 4719 | |
9771b263 | 4720 | FOR_EACH_VEC_ELT (dependence_relations, i, ddr) |
86df10e3 | 4721 | { |
86df10e3 SP |
4722 | if (chrec_contains_undetermined (DDR_ARE_DEPENDENT (ddr))) |
4723 | nb_top_relations++; | |
b8698a0f | 4724 | |
86df10e3 | 4725 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
5006671f | 4726 | nb_bot_relations++; |
b8698a0f L |
4727 | |
4728 | else | |
86df10e3 SP |
4729 | nb_chrec_relations++; |
4730 | } | |
b8698a0f | 4731 | |
86df10e3 SP |
4732 | gather_stats_on_scev_database (); |
4733 | } | |
56cf8686 | 4734 | } |
36d59cf7 | 4735 | |
9771b263 | 4736 | loop_nest.release (); |
36d59cf7 DB |
4737 | free_dependence_relations (dependence_relations); |
4738 | free_data_refs (datarefs); | |
4739 | } | |
3d8864c0 SP |
4740 | |
4741 | /* Computes all the data dependences and check that the results of | |
4742 | several analyzers are the same. */ | |
4743 | ||
4744 | void | |
4745 | tree_check_data_deps (void) | |
4746 | { | |
4747 | loop_iterator li; | |
4748 | struct loop *loop_nest; | |
4749 | ||
4750 | FOR_EACH_LOOP (li, loop_nest, 0) | |
4751 | analyze_all_data_dependences (loop_nest); | |
4752 | } | |
36d59cf7 DB |
4753 | |
4754 | /* Free the memory used by a data dependence relation DDR. */ | |
4755 | ||
4756 | void | |
4757 | free_dependence_relation (struct data_dependence_relation *ddr) | |
4758 | { | |
4759 | if (ddr == NULL) | |
4760 | return; | |
4761 | ||
9771b263 | 4762 | if (DDR_SUBSCRIPTS (ddr).exists ()) |
d93817c4 | 4763 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
9771b263 DN |
4764 | DDR_DIST_VECTS (ddr).release (); |
4765 | DDR_DIR_VECTS (ddr).release (); | |
ebf78a47 | 4766 | |
36d59cf7 DB |
4767 | free (ddr); |
4768 | } | |
4769 | ||
4770 | /* Free the memory used by the data dependence relations from | |
4771 | DEPENDENCE_RELATIONS. */ | |
4772 | ||
b8698a0f | 4773 | void |
9771b263 | 4774 | free_dependence_relations (vec<ddr_p> dependence_relations) |
36d59cf7 DB |
4775 | { |
4776 | unsigned int i; | |
ebf78a47 | 4777 | struct data_dependence_relation *ddr; |
36d59cf7 | 4778 | |
9771b263 | 4779 | FOR_EACH_VEC_ELT (dependence_relations, i, ddr) |
01be8516 | 4780 | if (ddr) |
3ac57120 | 4781 | free_dependence_relation (ddr); |
ebf78a47 | 4782 | |
9771b263 | 4783 | dependence_relations.release (); |
56cf8686 SP |
4784 | } |
4785 | ||
36d59cf7 DB |
4786 | /* Free the memory used by the data references from DATAREFS. */ |
4787 | ||
4788 | void | |
9771b263 | 4789 | free_data_refs (vec<data_reference_p> datarefs) |
36d59cf7 DB |
4790 | { |
4791 | unsigned int i; | |
ebf78a47 | 4792 | struct data_reference *dr; |
56cf8686 | 4793 | |
9771b263 | 4794 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
8fdbc9c6 | 4795 | free_data_ref (dr); |
9771b263 | 4796 | datarefs.release (); |
36d59cf7 | 4797 | } |