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2146e26d | 1 | /* Data references and dependences detectors. |
3aea1f79 | 2 | Copyright (C) 2003-2014 Free Software Foundation, Inc. |
6b421feb | 3 | Contributed by Sebastian Pop <pop@cri.ensmp.fr> |
2146e26d | 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 | |
8c4c00c1 | 9 | Software Foundation; either version 3, or (at your option) any later |
2146e26d | 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 | |
8c4c00c1 | 18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
2146e26d | 20 | |
21 | /* This pass walks a given loop structure searching for array | |
22 | references. The information about the array accesses is recorded | |
48e1416a | 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 | |
2146e26d | 28 | the array is accessed twice at iterations x and y if and only if: |
29 | | chrec1 (x) == chrec2 (y). | |
48e1416a | 30 | |
2146e26d | 31 | The goals of this analysis are: |
48e1416a | 32 | |
2146e26d | 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), | |
48e1416a | 36 | |
2146e26d | 37 | - when two data references access the same data, to qualify the |
38 | dependence relation with classic dependence representations: | |
48e1416a | 39 | |
2146e26d | 40 | - distance vectors |
41 | - direction vectors | |
42 | - loop carried level dependence | |
43 | - polyhedron dependence | |
44 | or with the chains of recurrences based representation, | |
48e1416a | 45 | |
46 | - to define a knowledge base for storing the data dependence | |
2146e26d | 47 | information, |
48e1416a | 48 | |
2146e26d | 49 | - to define an interface to access this data. |
48e1416a | 50 | |
51 | ||
2146e26d | 52 | Definitions: |
48e1416a | 53 | |
2146e26d | 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 | |
48e1416a | 60 | solutions are integer constants, for example the equation |
2146e26d | 61 | | 3*x + 2*y = 1 |
62 | has an integer solution x = 1 and y = -1. | |
48e1416a | 63 | |
2146e26d | 64 | References: |
48e1416a | 65 | |
2146e26d | 66 | - "Advanced Compilation for High Performance Computing" by Randy |
67 | Allen and Ken Kennedy. | |
48e1416a | 68 | http://citeseer.ist.psu.edu/goff91practical.html |
69 | ||
70 | - "Loop Transformations for Restructuring Compilers - The Foundations" | |
2146e26d | 71 | by Utpal Banerjee. |
72 | ||
48e1416a | 73 | |
2146e26d | 74 | */ |
75 | ||
76 | #include "config.h" | |
77 | #include "system.h" | |
78 | #include "coretypes.h" | |
0d9585ca | 79 | #include "tree.h" |
9ed99284 | 80 | #include "expr.h" |
ce084dfc | 81 | #include "gimple-pretty-print.h" |
94ea8568 | 82 | #include "predict.h" |
83 | #include "vec.h" | |
84 | #include "hashtab.h" | |
85 | #include "hash-set.h" | |
86 | #include "machmode.h" | |
87 | #include "tm.h" | |
88 | #include "hard-reg-set.h" | |
89 | #include "input.h" | |
90 | #include "function.h" | |
91 | #include "dominance.h" | |
92 | #include "cfg.h" | |
bc61cadb | 93 | #include "basic-block.h" |
94 | #include "tree-ssa-alias.h" | |
95 | #include "internal-fn.h" | |
96 | #include "gimple-expr.h" | |
97 | #include "is-a.h" | |
073c1fd5 | 98 | #include "gimple.h" |
dcf1a1ec | 99 | #include "gimple-iterator.h" |
05d9c18a | 100 | #include "tree-ssa-loop-niter.h" |
073c1fd5 | 101 | #include "tree-ssa-loop.h" |
69ee5dbb | 102 | #include "tree-ssa.h" |
2146e26d | 103 | #include "cfgloop.h" |
2146e26d | 104 | #include "tree-data-ref.h" |
105 | #include "tree-scalar-evolution.h" | |
b9ed1410 | 106 | #include "dumpfile.h" |
faa56cf9 | 107 | #include "langhooks.h" |
5fc88ffd | 108 | #include "tree-affine.h" |
c7af8ae7 | 109 | #include "params.h" |
2146e26d | 110 | |
6b421feb | 111 | static struct datadep_stats |
112 | { | |
113 | int num_dependence_tests; | |
114 | int num_dependence_dependent; | |
115 | int num_dependence_independent; | |
116 | int num_dependence_undetermined; | |
117 | ||
118 | int num_subscript_tests; | |
119 | int num_subscript_undetermined; | |
120 | int num_same_subscript_function; | |
121 | ||
122 | int num_ziv; | |
123 | int num_ziv_independent; | |
124 | int num_ziv_dependent; | |
125 | int num_ziv_unimplemented; | |
126 | ||
127 | int num_siv; | |
128 | int num_siv_independent; | |
129 | int num_siv_dependent; | |
130 | int num_siv_unimplemented; | |
131 | ||
132 | int num_miv; | |
133 | int num_miv_independent; | |
134 | int num_miv_dependent; | |
135 | int num_miv_unimplemented; | |
136 | } dependence_stats; | |
137 | ||
b44d1046 | 138 | static bool subscript_dependence_tester_1 (struct data_dependence_relation *, |
139 | struct data_reference *, | |
8c7b1d8e | 140 | struct data_reference *, |
141 | struct loop *); | |
2146e26d | 142 | /* Returns true iff A divides B. */ |
143 | ||
48e1416a | 144 | static inline bool |
7ecb5bb2 | 145 | tree_fold_divides_p (const_tree a, const_tree b) |
2146e26d | 146 | { |
426a138f | 147 | gcc_assert (TREE_CODE (a) == INTEGER_CST); |
148 | gcc_assert (TREE_CODE (b) == INTEGER_CST); | |
317e2a67 | 149 | return integer_zerop (int_const_binop (TRUNC_MOD_EXPR, b, a)); |
2146e26d | 150 | } |
151 | ||
bc3c8ad4 | 152 | /* Returns true iff A divides B. */ |
153 | ||
48e1416a | 154 | static inline bool |
bc3c8ad4 | 155 | int_divides_p (int a, int b) |
156 | { | |
157 | return ((b % a) == 0); | |
2146e26d | 158 | } |
159 | ||
160 | \f | |
161 | ||
48e1416a | 162 | /* Dump into FILE all the data references from DATAREFS. */ |
2146e26d | 163 | |
d129ada0 | 164 | static void |
f1f41a6c | 165 | dump_data_references (FILE *file, vec<data_reference_p> datarefs) |
2146e26d | 166 | { |
167 | unsigned int i; | |
41c7a324 | 168 | struct data_reference *dr; |
169 | ||
f1f41a6c | 170 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
41c7a324 | 171 | dump_data_reference (file, dr); |
2146e26d | 172 | } |
173 | ||
c7d89805 | 174 | /* Unified dump into FILE all the data references from DATAREFS. */ |
175 | ||
176 | DEBUG_FUNCTION void | |
177 | debug (vec<data_reference_p> &ref) | |
178 | { | |
179 | dump_data_references (stderr, ref); | |
180 | } | |
181 | ||
182 | DEBUG_FUNCTION void | |
183 | debug (vec<data_reference_p> *ptr) | |
184 | { | |
185 | if (ptr) | |
186 | debug (*ptr); | |
187 | else | |
188 | fprintf (stderr, "<nil>\n"); | |
189 | } | |
190 | ||
191 | ||
48e1416a | 192 | /* Dump into STDERR all the data references from DATAREFS. */ |
5df4cc8d | 193 | |
4b987fac | 194 | DEBUG_FUNCTION void |
f1f41a6c | 195 | debug_data_references (vec<data_reference_p> datarefs) |
5df4cc8d | 196 | { |
197 | dump_data_references (stderr, datarefs); | |
198 | } | |
199 | ||
5df4cc8d | 200 | /* Print to STDERR the data_reference DR. */ |
201 | ||
4b987fac | 202 | DEBUG_FUNCTION void |
5df4cc8d | 203 | debug_data_reference (struct data_reference *dr) |
204 | { | |
205 | dump_data_reference (stderr, dr); | |
206 | } | |
207 | ||
2146e26d | 208 | /* Dump function for a DATA_REFERENCE structure. */ |
209 | ||
48e1416a | 210 | void |
211 | dump_data_reference (FILE *outf, | |
2146e26d | 212 | struct data_reference *dr) |
213 | { | |
214 | unsigned int i; | |
48e1416a | 215 | |
b40e3432 | 216 | fprintf (outf, "#(Data Ref: \n"); |
217 | fprintf (outf, "# bb: %d \n", gimple_bb (DR_STMT (dr))->index); | |
218 | fprintf (outf, "# stmt: "); | |
75a70cf9 | 219 | print_gimple_stmt (outf, DR_STMT (dr), 0, 0); |
5dc5fe13 | 220 | fprintf (outf, "# ref: "); |
2146e26d | 221 | print_generic_stmt (outf, DR_REF (dr), 0); |
5dc5fe13 | 222 | fprintf (outf, "# base_object: "); |
516849c7 | 223 | print_generic_stmt (outf, DR_BASE_OBJECT (dr), 0); |
48e1416a | 224 | |
2146e26d | 225 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
226 | { | |
5dc5fe13 | 227 | fprintf (outf, "# Access function %d: ", i); |
2146e26d | 228 | print_generic_stmt (outf, DR_ACCESS_FN (dr, i), 0); |
229 | } | |
5dc5fe13 | 230 | fprintf (outf, "#)\n"); |
2146e26d | 231 | } |
232 | ||
c7d89805 | 233 | /* Unified dump function for a DATA_REFERENCE structure. */ |
234 | ||
235 | DEBUG_FUNCTION void | |
236 | debug (data_reference &ref) | |
237 | { | |
238 | dump_data_reference (stderr, &ref); | |
239 | } | |
240 | ||
241 | DEBUG_FUNCTION void | |
242 | debug (data_reference *ptr) | |
243 | { | |
244 | if (ptr) | |
245 | debug (*ptr); | |
246 | else | |
247 | fprintf (stderr, "<nil>\n"); | |
248 | } | |
249 | ||
250 | ||
87da4f2e | 251 | /* Dumps the affine function described by FN to the file OUTF. */ |
252 | ||
253 | static void | |
254 | dump_affine_function (FILE *outf, affine_fn fn) | |
255 | { | |
256 | unsigned i; | |
257 | tree coef; | |
258 | ||
f1f41a6c | 259 | print_generic_expr (outf, fn[0], TDF_SLIM); |
260 | for (i = 1; fn.iterate (i, &coef); i++) | |
87da4f2e | 261 | { |
262 | fprintf (outf, " + "); | |
263 | print_generic_expr (outf, coef, TDF_SLIM); | |
264 | fprintf (outf, " * x_%u", i); | |
265 | } | |
266 | } | |
267 | ||
268 | /* Dumps the conflict function CF to the file OUTF. */ | |
269 | ||
270 | static void | |
271 | dump_conflict_function (FILE *outf, conflict_function *cf) | |
272 | { | |
273 | unsigned i; | |
274 | ||
275 | if (cf->n == NO_DEPENDENCE) | |
984cebc1 | 276 | fprintf (outf, "no dependence"); |
87da4f2e | 277 | else if (cf->n == NOT_KNOWN) |
984cebc1 | 278 | fprintf (outf, "not known"); |
87da4f2e | 279 | else |
280 | { | |
281 | for (i = 0; i < cf->n; i++) | |
282 | { | |
984cebc1 | 283 | if (i != 0) |
284 | fprintf (outf, " "); | |
87da4f2e | 285 | fprintf (outf, "["); |
286 | dump_affine_function (outf, cf->fns[i]); | |
984cebc1 | 287 | fprintf (outf, "]"); |
87da4f2e | 288 | } |
289 | } | |
290 | } | |
291 | ||
bc3c8ad4 | 292 | /* Dump function for a SUBSCRIPT structure. */ |
293 | ||
d129ada0 | 294 | static void |
bc3c8ad4 | 295 | dump_subscript (FILE *outf, struct subscript *subscript) |
296 | { | |
87da4f2e | 297 | conflict_function *cf = SUB_CONFLICTS_IN_A (subscript); |
bc3c8ad4 | 298 | |
299 | fprintf (outf, "\n (subscript \n"); | |
300 | fprintf (outf, " iterations_that_access_an_element_twice_in_A: "); | |
87da4f2e | 301 | dump_conflict_function (outf, cf); |
302 | if (CF_NONTRIVIAL_P (cf)) | |
bc3c8ad4 | 303 | { |
304 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
984cebc1 | 305 | fprintf (outf, "\n last_conflict: "); |
306 | print_generic_expr (outf, last_iteration, 0); | |
bc3c8ad4 | 307 | } |
48e1416a | 308 | |
87da4f2e | 309 | cf = SUB_CONFLICTS_IN_B (subscript); |
984cebc1 | 310 | fprintf (outf, "\n iterations_that_access_an_element_twice_in_B: "); |
87da4f2e | 311 | dump_conflict_function (outf, cf); |
312 | if (CF_NONTRIVIAL_P (cf)) | |
bc3c8ad4 | 313 | { |
314 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
984cebc1 | 315 | fprintf (outf, "\n last_conflict: "); |
316 | print_generic_expr (outf, last_iteration, 0); | |
bc3c8ad4 | 317 | } |
318 | ||
984cebc1 | 319 | fprintf (outf, "\n (Subscript distance: "); |
320 | print_generic_expr (outf, SUB_DISTANCE (subscript), 0); | |
321 | fprintf (outf, " ))\n"); | |
bc3c8ad4 | 322 | } |
323 | ||
6b421feb | 324 | /* Print the classic direction vector DIRV to OUTF. */ |
325 | ||
d129ada0 | 326 | static void |
6b421feb | 327 | print_direction_vector (FILE *outf, |
328 | lambda_vector dirv, | |
329 | int length) | |
330 | { | |
331 | int eq; | |
332 | ||
333 | for (eq = 0; eq < length; eq++) | |
334 | { | |
bc620c5c | 335 | enum data_dependence_direction dir = ((enum data_dependence_direction) |
336 | dirv[eq]); | |
6b421feb | 337 | |
338 | switch (dir) | |
339 | { | |
340 | case dir_positive: | |
341 | fprintf (outf, " +"); | |
342 | break; | |
343 | case dir_negative: | |
344 | fprintf (outf, " -"); | |
345 | break; | |
346 | case dir_equal: | |
347 | fprintf (outf, " ="); | |
348 | break; | |
349 | case dir_positive_or_equal: | |
350 | fprintf (outf, " +="); | |
351 | break; | |
352 | case dir_positive_or_negative: | |
353 | fprintf (outf, " +-"); | |
354 | break; | |
355 | case dir_negative_or_equal: | |
356 | fprintf (outf, " -="); | |
357 | break; | |
358 | case dir_star: | |
359 | fprintf (outf, " *"); | |
360 | break; | |
361 | default: | |
362 | fprintf (outf, "indep"); | |
363 | break; | |
364 | } | |
365 | } | |
366 | fprintf (outf, "\n"); | |
367 | } | |
368 | ||
b44d1046 | 369 | /* Print a vector of direction vectors. */ |
370 | ||
d129ada0 | 371 | static void |
f1f41a6c | 372 | print_dir_vectors (FILE *outf, vec<lambda_vector> dir_vects, |
b44d1046 | 373 | int length) |
374 | { | |
375 | unsigned j; | |
376 | lambda_vector v; | |
377 | ||
f1f41a6c | 378 | FOR_EACH_VEC_ELT (dir_vects, j, v) |
b44d1046 | 379 | print_direction_vector (outf, v, length); |
380 | } | |
381 | ||
e01f9f1f | 382 | /* Print out a vector VEC of length N to OUTFILE. */ |
383 | ||
384 | static inline void | |
385 | print_lambda_vector (FILE * outfile, lambda_vector vector, int n) | |
386 | { | |
387 | int i; | |
388 | ||
389 | for (i = 0; i < n; i++) | |
390 | fprintf (outfile, "%3d ", vector[i]); | |
391 | fprintf (outfile, "\n"); | |
392 | } | |
393 | ||
b44d1046 | 394 | /* Print a vector of distance vectors. */ |
395 | ||
d129ada0 | 396 | static void |
f1f41a6c | 397 | print_dist_vectors (FILE *outf, vec<lambda_vector> dist_vects, |
d129ada0 | 398 | int length) |
b44d1046 | 399 | { |
400 | unsigned j; | |
401 | lambda_vector v; | |
402 | ||
f1f41a6c | 403 | FOR_EACH_VEC_ELT (dist_vects, j, v) |
b44d1046 | 404 | print_lambda_vector (outf, v, length); |
405 | } | |
406 | ||
2146e26d | 407 | /* Dump function for a DATA_DEPENDENCE_RELATION structure. */ |
408 | ||
d129ada0 | 409 | static void |
48e1416a | 410 | dump_data_dependence_relation (FILE *outf, |
2146e26d | 411 | struct data_dependence_relation *ddr) |
412 | { | |
2146e26d | 413 | struct data_reference *dra, *drb; |
bc3c8ad4 | 414 | |
bc3c8ad4 | 415 | fprintf (outf, "(Data Dep: \n"); |
801c5610 | 416 | |
4cc34f6b | 417 | if (!ddr || DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) |
418 | { | |
be2e5c02 | 419 | if (ddr) |
420 | { | |
421 | dra = DDR_A (ddr); | |
422 | drb = DDR_B (ddr); | |
423 | if (dra) | |
424 | dump_data_reference (outf, dra); | |
425 | else | |
426 | fprintf (outf, " (nil)\n"); | |
427 | if (drb) | |
428 | dump_data_reference (outf, drb); | |
429 | else | |
430 | fprintf (outf, " (nil)\n"); | |
431 | } | |
4cc34f6b | 432 | fprintf (outf, " (don't know)\n)\n"); |
433 | return; | |
434 | } | |
435 | ||
436 | dra = DDR_A (ddr); | |
437 | drb = DDR_B (ddr); | |
801c5610 | 438 | dump_data_reference (outf, dra); |
439 | dump_data_reference (outf, drb); | |
440 | ||
4cc34f6b | 441 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
2146e26d | 442 | fprintf (outf, " (no dependence)\n"); |
48e1416a | 443 | |
bc3c8ad4 | 444 | else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
2146e26d | 445 | { |
bc3c8ad4 | 446 | unsigned int i; |
b44d1046 | 447 | struct loop *loopi; |
1532ec98 | 448 | |
2146e26d | 449 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
450 | { | |
2146e26d | 451 | fprintf (outf, " access_fn_A: "); |
452 | print_generic_stmt (outf, DR_ACCESS_FN (dra, i), 0); | |
453 | fprintf (outf, " access_fn_B: "); | |
454 | print_generic_stmt (outf, DR_ACCESS_FN (drb, i), 0); | |
bc3c8ad4 | 455 | dump_subscript (outf, DDR_SUBSCRIPT (ddr, i)); |
2146e26d | 456 | } |
1532ec98 | 457 | |
355572cc | 458 | fprintf (outf, " inner loop index: %d\n", DDR_INNER_LOOP (ddr)); |
b44d1046 | 459 | fprintf (outf, " loop nest: ("); |
f1f41a6c | 460 | FOR_EACH_VEC_ELT (DDR_LOOP_NEST (ddr), i, loopi) |
b44d1046 | 461 | fprintf (outf, "%d ", loopi->num); |
462 | fprintf (outf, ")\n"); | |
463 | ||
1532ec98 | 464 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) |
2146e26d | 465 | { |
1532ec98 | 466 | fprintf (outf, " distance_vector: "); |
467 | print_lambda_vector (outf, DDR_DIST_VECT (ddr, i), | |
b44d1046 | 468 | DDR_NB_LOOPS (ddr)); |
bc3c8ad4 | 469 | } |
1532ec98 | 470 | |
471 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
bc3c8ad4 | 472 | { |
1532ec98 | 473 | fprintf (outf, " direction_vector: "); |
6b421feb | 474 | print_direction_vector (outf, DDR_DIR_VECT (ddr, i), |
b44d1046 | 475 | DDR_NB_LOOPS (ddr)); |
2146e26d | 476 | } |
2146e26d | 477 | } |
478 | ||
479 | fprintf (outf, ")\n"); | |
480 | } | |
481 | ||
d129ada0 | 482 | /* Debug version. */ |
2146e26d | 483 | |
d129ada0 | 484 | DEBUG_FUNCTION void |
485 | debug_data_dependence_relation (struct data_dependence_relation *ddr) | |
2146e26d | 486 | { |
d129ada0 | 487 | dump_data_dependence_relation (stderr, ddr); |
488 | } | |
48e1416a | 489 | |
d129ada0 | 490 | /* Dump into FILE all the dependence relations from DDRS. */ |
48e1416a | 491 | |
d129ada0 | 492 | void |
493 | dump_data_dependence_relations (FILE *file, | |
f1f41a6c | 494 | vec<ddr_p> ddrs) |
d129ada0 | 495 | { |
496 | unsigned int i; | |
497 | struct data_dependence_relation *ddr; | |
48e1416a | 498 | |
f1f41a6c | 499 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
d129ada0 | 500 | dump_data_dependence_relation (file, ddr); |
501 | } | |
48e1416a | 502 | |
c7d89805 | 503 | DEBUG_FUNCTION void |
504 | debug (vec<ddr_p> &ref) | |
505 | { | |
506 | dump_data_dependence_relations (stderr, ref); | |
507 | } | |
508 | ||
509 | DEBUG_FUNCTION void | |
510 | debug (vec<ddr_p> *ptr) | |
511 | { | |
512 | if (ptr) | |
513 | debug (*ptr); | |
514 | else | |
515 | fprintf (stderr, "<nil>\n"); | |
516 | } | |
517 | ||
518 | ||
d129ada0 | 519 | /* Dump to STDERR all the dependence relations from DDRS. */ |
48e1416a | 520 | |
d129ada0 | 521 | DEBUG_FUNCTION void |
f1f41a6c | 522 | debug_data_dependence_relations (vec<ddr_p> ddrs) |
d129ada0 | 523 | { |
524 | dump_data_dependence_relations (stderr, ddrs); | |
2146e26d | 525 | } |
526 | ||
bc3c8ad4 | 527 | /* Dumps the distance and direction vectors in FILE. DDRS contains |
528 | the dependence relations, and VECT_SIZE is the size of the | |
529 | dependence vectors, or in other words the number of loops in the | |
530 | considered nest. */ | |
531 | ||
d129ada0 | 532 | static void |
f1f41a6c | 533 | dump_dist_dir_vectors (FILE *file, vec<ddr_p> ddrs) |
bc3c8ad4 | 534 | { |
1532ec98 | 535 | unsigned int i, j; |
41c7a324 | 536 | struct data_dependence_relation *ddr; |
537 | lambda_vector v; | |
bc3c8ad4 | 538 | |
f1f41a6c | 539 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
41c7a324 | 540 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_AFFINE_P (ddr)) |
541 | { | |
f1f41a6c | 542 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), j, v) |
41c7a324 | 543 | { |
544 | fprintf (file, "DISTANCE_V ("); | |
545 | print_lambda_vector (file, v, DDR_NB_LOOPS (ddr)); | |
546 | fprintf (file, ")\n"); | |
547 | } | |
548 | ||
f1f41a6c | 549 | FOR_EACH_VEC_ELT (DDR_DIR_VECTS (ddr), j, v) |
41c7a324 | 550 | { |
551 | fprintf (file, "DIRECTION_V ("); | |
552 | print_direction_vector (file, v, DDR_NB_LOOPS (ddr)); | |
553 | fprintf (file, ")\n"); | |
554 | } | |
555 | } | |
1532ec98 | 556 | |
bc3c8ad4 | 557 | fprintf (file, "\n\n"); |
558 | } | |
559 | ||
560 | /* Dumps the data dependence relations DDRS in FILE. */ | |
561 | ||
d129ada0 | 562 | static void |
f1f41a6c | 563 | dump_ddrs (FILE *file, vec<ddr_p> ddrs) |
bc3c8ad4 | 564 | { |
565 | unsigned int i; | |
41c7a324 | 566 | struct data_dependence_relation *ddr; |
567 | ||
f1f41a6c | 568 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
41c7a324 | 569 | dump_data_dependence_relation (file, ddr); |
bc3c8ad4 | 570 | |
bc3c8ad4 | 571 | fprintf (file, "\n\n"); |
572 | } | |
573 | ||
d129ada0 | 574 | DEBUG_FUNCTION void |
f1f41a6c | 575 | debug_ddrs (vec<ddr_p> ddrs) |
d129ada0 | 576 | { |
577 | dump_ddrs (stderr, ddrs); | |
578 | } | |
579 | ||
75a70cf9 | 580 | /* Helper function for split_constant_offset. Expresses OP0 CODE OP1 |
581 | (the type of the result is TYPE) as VAR + OFF, where OFF is a nonzero | |
582 | constant of type ssizetype, and returns true. If we cannot do this | |
583 | with OFF nonzero, OFF and VAR are set to NULL_TREE instead and false | |
584 | is returned. */ | |
516849c7 | 585 | |
75a70cf9 | 586 | static bool |
587 | split_constant_offset_1 (tree type, tree op0, enum tree_code code, tree op1, | |
588 | tree *var, tree *off) | |
516849c7 | 589 | { |
80bb306a | 590 | tree var0, var1; |
591 | tree off0, off1; | |
75a70cf9 | 592 | enum tree_code ocode = code; |
516849c7 | 593 | |
75a70cf9 | 594 | *var = NULL_TREE; |
595 | *off = NULL_TREE; | |
516849c7 | 596 | |
0de36bdb | 597 | switch (code) |
516849c7 | 598 | { |
80bb306a | 599 | case INTEGER_CST: |
600 | *var = build_int_cst (type, 0); | |
75a70cf9 | 601 | *off = fold_convert (ssizetype, op0); |
602 | return true; | |
516849c7 | 603 | |
0de36bdb | 604 | case POINTER_PLUS_EXPR: |
75a70cf9 | 605 | ocode = PLUS_EXPR; |
0de36bdb | 606 | /* FALLTHROUGH */ |
80bb306a | 607 | case PLUS_EXPR: |
608 | case MINUS_EXPR: | |
75a70cf9 | 609 | split_constant_offset (op0, &var0, &off0); |
610 | split_constant_offset (op1, &var1, &off1); | |
611 | *var = fold_build2 (code, type, var0, var1); | |
612 | *off = size_binop (ocode, off0, off1); | |
613 | return true; | |
516849c7 | 614 | |
516849c7 | 615 | case MULT_EXPR: |
75a70cf9 | 616 | if (TREE_CODE (op1) != INTEGER_CST) |
617 | return false; | |
80bb306a | 618 | |
75a70cf9 | 619 | split_constant_offset (op0, &var0, &off0); |
620 | *var = fold_build2 (MULT_EXPR, type, var0, op1); | |
621 | *off = size_binop (MULT_EXPR, off0, fold_convert (ssizetype, op1)); | |
622 | return true; | |
516849c7 | 623 | |
80bb306a | 624 | case ADDR_EXPR: |
625 | { | |
75a70cf9 | 626 | tree base, poffset; |
80bb306a | 627 | HOST_WIDE_INT pbitsize, pbitpos; |
3754d046 | 628 | machine_mode pmode; |
80bb306a | 629 | int punsignedp, pvolatilep; |
516849c7 | 630 | |
97d819e5 | 631 | op0 = TREE_OPERAND (op0, 0); |
75a70cf9 | 632 | base = get_inner_reference (op0, &pbitsize, &pbitpos, &poffset, |
80bb306a | 633 | &pmode, &punsignedp, &pvolatilep, false); |
516849c7 | 634 | |
80bb306a | 635 | if (pbitpos % BITS_PER_UNIT != 0) |
75a70cf9 | 636 | return false; |
80bb306a | 637 | base = build_fold_addr_expr (base); |
638 | off0 = ssize_int (pbitpos / BITS_PER_UNIT); | |
516849c7 | 639 | |
80bb306a | 640 | if (poffset) |
641 | { | |
642 | split_constant_offset (poffset, &poffset, &off1); | |
643 | off0 = size_binop (PLUS_EXPR, off0, off1); | |
55ed4df6 | 644 | if (POINTER_TYPE_P (TREE_TYPE (base))) |
2cc66f2a | 645 | base = fold_build_pointer_plus (base, poffset); |
55ed4df6 | 646 | else |
647 | base = fold_build2 (PLUS_EXPR, TREE_TYPE (base), base, | |
648 | fold_convert (TREE_TYPE (base), poffset)); | |
80bb306a | 649 | } |
650 | ||
69a83716 | 651 | var0 = fold_convert (type, base); |
652 | ||
653 | /* If variable length types are involved, punt, otherwise casts | |
654 | might be converted into ARRAY_REFs in gimplify_conversion. | |
655 | To compute that ARRAY_REF's element size TYPE_SIZE_UNIT, which | |
656 | possibly no longer appears in current GIMPLE, might resurface. | |
657 | This perhaps could run | |
d9659041 | 658 | if (CONVERT_EXPR_P (var0)) |
69a83716 | 659 | { |
660 | gimplify_conversion (&var0); | |
661 | // Attempt to fill in any within var0 found ARRAY_REF's | |
662 | // element size from corresponding op embedded ARRAY_REF, | |
663 | // if unsuccessful, just punt. | |
664 | } */ | |
665 | while (POINTER_TYPE_P (type)) | |
666 | type = TREE_TYPE (type); | |
667 | if (int_size_in_bytes (type) < 0) | |
75a70cf9 | 668 | return false; |
69a83716 | 669 | |
670 | *var = var0; | |
80bb306a | 671 | *off = off0; |
75a70cf9 | 672 | return true; |
80bb306a | 673 | } |
516849c7 | 674 | |
a091367a | 675 | case SSA_NAME: |
676 | { | |
75a70cf9 | 677 | gimple def_stmt = SSA_NAME_DEF_STMT (op0); |
678 | enum tree_code subcode; | |
a091367a | 679 | |
75a70cf9 | 680 | if (gimple_code (def_stmt) != GIMPLE_ASSIGN) |
681 | return false; | |
682 | ||
683 | var0 = gimple_assign_rhs1 (def_stmt); | |
684 | subcode = gimple_assign_rhs_code (def_stmt); | |
685 | var1 = gimple_assign_rhs2 (def_stmt); | |
686 | ||
687 | return split_constant_offset_1 (type, var0, subcode, var1, var, off); | |
a091367a | 688 | } |
be2e5c02 | 689 | CASE_CONVERT: |
690 | { | |
691 | /* We must not introduce undefined overflow, and we must not change the value. | |
692 | Hence we're okay if the inner type doesn't overflow to start with | |
693 | (pointer or signed), the outer type also is an integer or pointer | |
694 | and the outer precision is at least as large as the inner. */ | |
695 | tree itype = TREE_TYPE (op0); | |
696 | if ((POINTER_TYPE_P (itype) | |
697 | || (INTEGRAL_TYPE_P (itype) && TYPE_OVERFLOW_UNDEFINED (itype))) | |
698 | && TYPE_PRECISION (type) >= TYPE_PRECISION (itype) | |
699 | && (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type))) | |
700 | { | |
701 | split_constant_offset (op0, &var0, off); | |
702 | *var = fold_convert (type, var0); | |
703 | return true; | |
704 | } | |
705 | return false; | |
706 | } | |
a091367a | 707 | |
516849c7 | 708 | default: |
75a70cf9 | 709 | return false; |
516849c7 | 710 | } |
75a70cf9 | 711 | } |
712 | ||
713 | /* Expresses EXP as VAR + OFF, where off is a constant. The type of OFF | |
714 | will be ssizetype. */ | |
715 | ||
716 | void | |
717 | split_constant_offset (tree exp, tree *var, tree *off) | |
718 | { | |
719 | tree type = TREE_TYPE (exp), otype, op0, op1, e, o; | |
720 | enum tree_code code; | |
516849c7 | 721 | |
75a70cf9 | 722 | *var = exp; |
80bb306a | 723 | *off = ssize_int (0); |
75a70cf9 | 724 | STRIP_NOPS (exp); |
725 | ||
32246fd4 | 726 | if (tree_is_chrec (exp) |
727 | || get_gimple_rhs_class (TREE_CODE (exp)) == GIMPLE_TERNARY_RHS) | |
75a70cf9 | 728 | return; |
729 | ||
730 | otype = TREE_TYPE (exp); | |
731 | code = TREE_CODE (exp); | |
732 | extract_ops_from_tree (exp, &code, &op0, &op1); | |
733 | if (split_constant_offset_1 (otype, op0, code, op1, &e, &o)) | |
734 | { | |
735 | *var = fold_convert (type, e); | |
736 | *off = o; | |
737 | } | |
516849c7 | 738 | } |
739 | ||
80bb306a | 740 | /* Returns the address ADDR of an object in a canonical shape (without nop |
741 | casts, and with type of pointer to the object). */ | |
516849c7 | 742 | |
743 | static tree | |
80bb306a | 744 | canonicalize_base_object_address (tree addr) |
516849c7 | 745 | { |
ad4a85ad | 746 | tree orig = addr; |
747 | ||
80bb306a | 748 | STRIP_NOPS (addr); |
516849c7 | 749 | |
ad4a85ad | 750 | /* The base address may be obtained by casting from integer, in that case |
751 | keep the cast. */ | |
752 | if (!POINTER_TYPE_P (TREE_TYPE (addr))) | |
753 | return orig; | |
754 | ||
80bb306a | 755 | if (TREE_CODE (addr) != ADDR_EXPR) |
756 | return addr; | |
516849c7 | 757 | |
80bb306a | 758 | return build_fold_addr_expr (TREE_OPERAND (addr, 0)); |
516849c7 | 759 | } |
760 | ||
48e1416a | 761 | /* Analyzes the behavior of the memory reference DR in the innermost loop or |
0c257e4c | 762 | basic block that contains it. Returns true if analysis succeed or false |
37545e54 | 763 | otherwise. */ |
516849c7 | 764 | |
880734c8 | 765 | bool |
0c257e4c | 766 | dr_analyze_innermost (struct data_reference *dr, struct loop *nest) |
516849c7 | 767 | { |
75a70cf9 | 768 | gimple stmt = DR_STMT (dr); |
80bb306a | 769 | struct loop *loop = loop_containing_stmt (stmt); |
770 | tree ref = DR_REF (dr); | |
516849c7 | 771 | HOST_WIDE_INT pbitsize, pbitpos; |
80bb306a | 772 | tree base, poffset; |
3754d046 | 773 | machine_mode pmode; |
516849c7 | 774 | int punsignedp, pvolatilep; |
80bb306a | 775 | affine_iv base_iv, offset_iv; |
776 | tree init, dinit, step; | |
37545e54 | 777 | bool in_loop = (loop && loop->num); |
80bb306a | 778 | |
779 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
780 | fprintf (dump_file, "analyze_innermost: "); | |
516849c7 | 781 | |
80bb306a | 782 | base = get_inner_reference (ref, &pbitsize, &pbitpos, &poffset, |
783 | &pmode, &punsignedp, &pvolatilep, false); | |
784 | gcc_assert (base != NULL_TREE); | |
516849c7 | 785 | |
80bb306a | 786 | if (pbitpos % BITS_PER_UNIT != 0) |
516849c7 | 787 | { |
80bb306a | 788 | if (dump_file && (dump_flags & TDF_DETAILS)) |
789 | fprintf (dump_file, "failed: bit offset alignment.\n"); | |
880734c8 | 790 | return false; |
80bb306a | 791 | } |
516849c7 | 792 | |
182cf5a9 | 793 | if (TREE_CODE (base) == MEM_REF) |
794 | { | |
795 | if (!integer_zerop (TREE_OPERAND (base, 1))) | |
796 | { | |
5de9d3ed | 797 | offset_int moff = mem_ref_offset (base); |
e913b5cd | 798 | tree mofft = wide_int_to_tree (sizetype, moff); |
182cf5a9 | 799 | if (!poffset) |
7667733b | 800 | poffset = mofft; |
182cf5a9 | 801 | else |
7667733b | 802 | poffset = size_binop (PLUS_EXPR, poffset, mofft); |
182cf5a9 | 803 | } |
804 | base = TREE_OPERAND (base, 0); | |
805 | } | |
806 | else | |
807 | base = build_fold_addr_expr (base); | |
0c257e4c | 808 | |
37545e54 | 809 | if (in_loop) |
80bb306a | 810 | { |
48e1416a | 811 | if (!simple_iv (loop, loop_containing_stmt (stmt), base, &base_iv, |
f634c3e9 | 812 | nest ? true : false)) |
37545e54 | 813 | { |
0c257e4c | 814 | if (nest) |
815 | { | |
816 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
817 | fprintf (dump_file, "failed: evolution of base is not" | |
818 | " affine.\n"); | |
819 | return false; | |
820 | } | |
821 | else | |
822 | { | |
823 | base_iv.base = base; | |
824 | base_iv.step = ssize_int (0); | |
825 | base_iv.no_overflow = true; | |
826 | } | |
37545e54 | 827 | } |
828 | } | |
829 | else | |
830 | { | |
831 | base_iv.base = base; | |
832 | base_iv.step = ssize_int (0); | |
833 | base_iv.no_overflow = true; | |
80bb306a | 834 | } |
37545e54 | 835 | |
dd2644cf | 836 | if (!poffset) |
80bb306a | 837 | { |
838 | offset_iv.base = ssize_int (0); | |
839 | offset_iv.step = ssize_int (0); | |
840 | } | |
dd2644cf | 841 | else |
80bb306a | 842 | { |
dd2644cf | 843 | if (!in_loop) |
844 | { | |
845 | offset_iv.base = poffset; | |
846 | offset_iv.step = ssize_int (0); | |
847 | } | |
848 | else if (!simple_iv (loop, loop_containing_stmt (stmt), | |
f634c3e9 | 849 | poffset, &offset_iv, |
850 | nest ? true : false)) | |
dd2644cf | 851 | { |
0c257e4c | 852 | if (nest) |
853 | { | |
854 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
855 | fprintf (dump_file, "failed: evolution of offset is not" | |
856 | " affine.\n"); | |
857 | return false; | |
858 | } | |
859 | else | |
860 | { | |
861 | offset_iv.base = poffset; | |
862 | offset_iv.step = ssize_int (0); | |
863 | } | |
dd2644cf | 864 | } |
80bb306a | 865 | } |
516849c7 | 866 | |
80bb306a | 867 | init = ssize_int (pbitpos / BITS_PER_UNIT); |
868 | split_constant_offset (base_iv.base, &base_iv.base, &dinit); | |
869 | init = size_binop (PLUS_EXPR, init, dinit); | |
870 | split_constant_offset (offset_iv.base, &offset_iv.base, &dinit); | |
871 | init = size_binop (PLUS_EXPR, init, dinit); | |
516849c7 | 872 | |
80bb306a | 873 | step = size_binop (PLUS_EXPR, |
874 | fold_convert (ssizetype, base_iv.step), | |
875 | fold_convert (ssizetype, offset_iv.step)); | |
516849c7 | 876 | |
80bb306a | 877 | DR_BASE_ADDRESS (dr) = canonicalize_base_object_address (base_iv.base); |
516849c7 | 878 | |
80bb306a | 879 | DR_OFFSET (dr) = fold_convert (ssizetype, offset_iv.base); |
880 | DR_INIT (dr) = init; | |
881 | DR_STEP (dr) = step; | |
516849c7 | 882 | |
80bb306a | 883 | DR_ALIGNED_TO (dr) = size_int (highest_pow2_factor (offset_iv.base)); |
516849c7 | 884 | |
80bb306a | 885 | if (dump_file && (dump_flags & TDF_DETAILS)) |
886 | fprintf (dump_file, "success.\n"); | |
880734c8 | 887 | |
888 | return true; | |
80bb306a | 889 | } |
516849c7 | 890 | |
80bb306a | 891 | /* Determines the base object and the list of indices of memory reference |
221a697e | 892 | DR, analyzed in LOOP and instantiated in loop nest NEST. */ |
516849c7 | 893 | |
80bb306a | 894 | static void |
221a697e | 895 | dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop) |
80bb306a | 896 | { |
1e094109 | 897 | vec<tree> access_fns = vNULL; |
95539e1d | 898 | tree ref, op; |
93fc59e8 | 899 | tree base, off, access_fn; |
900 | basic_block before_loop; | |
48e1416a | 901 | |
93fc59e8 | 902 | /* If analyzing a basic-block there are no indices to analyze |
903 | and thus no access functions. */ | |
5fc88ffd | 904 | if (!nest) |
905 | { | |
93fc59e8 | 906 | DR_BASE_OBJECT (dr) = DR_REF (dr); |
f1f41a6c | 907 | DR_ACCESS_FNS (dr).create (0); |
5fc88ffd | 908 | return; |
909 | } | |
910 | ||
95539e1d | 911 | ref = DR_REF (dr); |
5fc88ffd | 912 | before_loop = block_before_loop (nest); |
48e1416a | 913 | |
93fc59e8 | 914 | /* REALPART_EXPR and IMAGPART_EXPR can be handled like accesses |
915 | into a two element array with a constant index. The base is | |
916 | then just the immediate underlying object. */ | |
917 | if (TREE_CODE (ref) == REALPART_EXPR) | |
918 | { | |
919 | ref = TREE_OPERAND (ref, 0); | |
f1f41a6c | 920 | access_fns.safe_push (integer_zero_node); |
93fc59e8 | 921 | } |
922 | else if (TREE_CODE (ref) == IMAGPART_EXPR) | |
923 | { | |
924 | ref = TREE_OPERAND (ref, 0); | |
f1f41a6c | 925 | access_fns.safe_push (integer_one_node); |
93fc59e8 | 926 | } |
927 | ||
bc4113a9 | 928 | /* Analyze access functions of dimensions we know to be independent. */ |
95539e1d | 929 | while (handled_component_p (ref)) |
516849c7 | 930 | { |
95539e1d | 931 | if (TREE_CODE (ref) == ARRAY_REF) |
516849c7 | 932 | { |
95539e1d | 933 | op = TREE_OPERAND (ref, 1); |
5fc88ffd | 934 | access_fn = analyze_scalar_evolution (loop, op); |
935 | access_fn = instantiate_scev (before_loop, loop, access_fn); | |
f1f41a6c | 936 | access_fns.safe_push (access_fn); |
bc4113a9 | 937 | } |
95539e1d | 938 | else if (TREE_CODE (ref) == COMPONENT_REF |
939 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (ref, 0))) == RECORD_TYPE) | |
940 | { | |
941 | /* For COMPONENT_REFs of records (but not unions!) use the | |
942 | FIELD_DECL offset as constant access function so we can | |
943 | disambiguate a[i].f1 and a[i].f2. */ | |
944 | tree off = component_ref_field_offset (ref); | |
945 | off = size_binop (PLUS_EXPR, | |
946 | size_binop (MULT_EXPR, | |
947 | fold_convert (bitsizetype, off), | |
948 | bitsize_int (BITS_PER_UNIT)), | |
949 | DECL_FIELD_BIT_OFFSET (TREE_OPERAND (ref, 1))); | |
f1f41a6c | 950 | access_fns.safe_push (off); |
95539e1d | 951 | } |
952 | else | |
953 | /* If we have an unhandled component we could not translate | |
954 | to an access function stop analyzing. We have determined | |
955 | our base object in this case. */ | |
956 | break; | |
48e1416a | 957 | |
95539e1d | 958 | ref = TREE_OPERAND (ref, 0); |
516849c7 | 959 | } |
960 | ||
0f00ec21 | 961 | /* If the address operand of a MEM_REF base has an evolution in the |
962 | analyzed nest, add it as an additional independent access-function. */ | |
95539e1d | 963 | if (TREE_CODE (ref) == MEM_REF) |
516849c7 | 964 | { |
95539e1d | 965 | op = TREE_OPERAND (ref, 0); |
80bb306a | 966 | access_fn = analyze_scalar_evolution (loop, op); |
089aa668 | 967 | access_fn = instantiate_scev (before_loop, loop, access_fn); |
0f00ec21 | 968 | if (TREE_CODE (access_fn) == POLYNOMIAL_CHREC) |
9488020c | 969 | { |
a927c5fa | 970 | tree orig_type; |
95539e1d | 971 | tree memoff = TREE_OPERAND (ref, 1); |
0f00ec21 | 972 | base = initial_condition (access_fn); |
a927c5fa | 973 | orig_type = TREE_TYPE (base); |
974 | STRIP_USELESS_TYPE_CONVERSION (base); | |
0f00ec21 | 975 | split_constant_offset (base, &base, &off); |
1e074e77 | 976 | STRIP_USELESS_TYPE_CONVERSION (base); |
0f00ec21 | 977 | /* Fold the MEM_REF offset into the evolutions initial |
978 | value to make more bases comparable. */ | |
95539e1d | 979 | if (!integer_zerop (memoff)) |
0f00ec21 | 980 | { |
981 | off = size_binop (PLUS_EXPR, off, | |
95539e1d | 982 | fold_convert (ssizetype, memoff)); |
983 | memoff = build_int_cst (TREE_TYPE (memoff), 0); | |
0f00ec21 | 984 | } |
985 | access_fn = chrec_replace_initial_condition | |
a927c5fa | 986 | (access_fn, fold_convert (orig_type, off)); |
95539e1d | 987 | /* ??? This is still not a suitable base object for |
988 | dr_may_alias_p - the base object needs to be an | |
989 | access that covers the object as whole. With | |
990 | an evolution in the pointer this cannot be | |
991 | guaranteed. | |
992 | As a band-aid, mark the access so we can special-case | |
993 | it in dr_may_alias_p. */ | |
994 | ref = fold_build2_loc (EXPR_LOCATION (ref), | |
995 | MEM_REF, TREE_TYPE (ref), | |
996 | base, memoff); | |
f1f41a6c | 997 | access_fns.safe_push (access_fn); |
9488020c | 998 | } |
516849c7 | 999 | } |
95539e1d | 1000 | else if (DECL_P (ref)) |
1001 | { | |
1002 | /* Canonicalize DR_BASE_OBJECT to MEM_REF form. */ | |
1003 | ref = build2 (MEM_REF, TREE_TYPE (ref), | |
1004 | build_fold_addr_expr (ref), | |
1005 | build_int_cst (reference_alias_ptr_type (ref), 0)); | |
1006 | } | |
516849c7 | 1007 | |
80bb306a | 1008 | DR_BASE_OBJECT (dr) = ref; |
1009 | DR_ACCESS_FNS (dr) = access_fns; | |
516849c7 | 1010 | } |
1011 | ||
80bb306a | 1012 | /* Extracts the alias analysis information from the memory reference DR. */ |
516849c7 | 1013 | |
80bb306a | 1014 | static void |
1015 | dr_analyze_alias (struct data_reference *dr) | |
516849c7 | 1016 | { |
80bb306a | 1017 | tree ref = DR_REF (dr); |
dd277d48 | 1018 | tree base = get_base_address (ref), addr; |
1019 | ||
182cf5a9 | 1020 | if (INDIRECT_REF_P (base) |
1021 | || TREE_CODE (base) == MEM_REF) | |
80bb306a | 1022 | { |
1023 | addr = TREE_OPERAND (base, 0); | |
1024 | if (TREE_CODE (addr) == SSA_NAME) | |
dd277d48 | 1025 | DR_PTR_INFO (dr) = SSA_NAME_PTR_INFO (addr); |
80bb306a | 1026 | } |
80bb306a | 1027 | } |
516849c7 | 1028 | |
80bb306a | 1029 | /* Frees data reference DR. */ |
31e389a2 | 1030 | |
801c5610 | 1031 | void |
31e389a2 | 1032 | free_data_ref (data_reference_p dr) |
1033 | { | |
f1f41a6c | 1034 | DR_ACCESS_FNS (dr).release (); |
31e389a2 | 1035 | free (dr); |
1036 | } | |
516849c7 | 1037 | |
80bb306a | 1038 | /* Analyzes memory reference MEMREF accessed in STMT. The reference |
1039 | is read if IS_READ is true, write otherwise. Returns the | |
221a697e | 1040 | data_reference description of MEMREF. NEST is the outermost loop |
1041 | in which the reference should be instantiated, LOOP is the loop in | |
1042 | which the data reference should be analyzed. */ | |
516849c7 | 1043 | |
5c205353 | 1044 | struct data_reference * |
221a697e | 1045 | create_data_ref (loop_p nest, loop_p loop, tree memref, gimple stmt, |
1046 | bool is_read) | |
516849c7 | 1047 | { |
80bb306a | 1048 | struct data_reference *dr; |
6b421feb | 1049 | |
80bb306a | 1050 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6b421feb | 1051 | { |
80bb306a | 1052 | fprintf (dump_file, "Creating dr for "); |
1053 | print_generic_expr (dump_file, memref, TDF_SLIM); | |
1054 | fprintf (dump_file, "\n"); | |
6b421feb | 1055 | } |
f84a688a | 1056 | |
80bb306a | 1057 | dr = XCNEW (struct data_reference); |
1058 | DR_STMT (dr) = stmt; | |
1059 | DR_REF (dr) = memref; | |
1060 | DR_IS_READ (dr) = is_read; | |
516849c7 | 1061 | |
0c257e4c | 1062 | dr_analyze_innermost (dr, nest); |
221a697e | 1063 | dr_analyze_indices (dr, nest, loop); |
80bb306a | 1064 | dr_analyze_alias (dr); |
516849c7 | 1065 | |
1066 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1067 | { | |
bc4113a9 | 1068 | unsigned i; |
80bb306a | 1069 | fprintf (dump_file, "\tbase_address: "); |
516849c7 | 1070 | print_generic_expr (dump_file, DR_BASE_ADDRESS (dr), TDF_SLIM); |
1071 | fprintf (dump_file, "\n\toffset from base address: "); | |
1072 | print_generic_expr (dump_file, DR_OFFSET (dr), TDF_SLIM); | |
1073 | fprintf (dump_file, "\n\tconstant offset from base address: "); | |
1074 | print_generic_expr (dump_file, DR_INIT (dr), TDF_SLIM); | |
516849c7 | 1075 | fprintf (dump_file, "\n\tstep: "); |
1076 | print_generic_expr (dump_file, DR_STEP (dr), TDF_SLIM); | |
80bb306a | 1077 | fprintf (dump_file, "\n\taligned to: "); |
1078 | print_generic_expr (dump_file, DR_ALIGNED_TO (dr), TDF_SLIM); | |
1079 | fprintf (dump_file, "\n\tbase_object: "); | |
1080 | print_generic_expr (dump_file, DR_BASE_OBJECT (dr), TDF_SLIM); | |
516849c7 | 1081 | fprintf (dump_file, "\n"); |
bc4113a9 | 1082 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
1083 | { | |
1084 | fprintf (dump_file, "\tAccess function %d: ", i); | |
1085 | print_generic_stmt (dump_file, DR_ACCESS_FN (dr, i), TDF_SLIM); | |
1086 | } | |
80bb306a | 1087 | } |
1088 | ||
48e1416a | 1089 | return dr; |
516849c7 | 1090 | } |
1091 | ||
ec611e12 | 1092 | /* Check if OFFSET1 and OFFSET2 (DR_OFFSETs of some data-refs) are identical |
1093 | expressions. */ | |
1094 | static bool | |
1095 | dr_equal_offsets_p1 (tree offset1, tree offset2) | |
1096 | { | |
1097 | bool res; | |
1098 | ||
1099 | STRIP_NOPS (offset1); | |
1100 | STRIP_NOPS (offset2); | |
1101 | ||
1102 | if (offset1 == offset2) | |
1103 | return true; | |
1104 | ||
1105 | if (TREE_CODE (offset1) != TREE_CODE (offset2) | |
1106 | || (!BINARY_CLASS_P (offset1) && !UNARY_CLASS_P (offset1))) | |
1107 | return false; | |
1108 | ||
1109 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 0), | |
1110 | TREE_OPERAND (offset2, 0)); | |
1111 | ||
1112 | if (!res || !BINARY_CLASS_P (offset1)) | |
1113 | return res; | |
1114 | ||
1115 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 1), | |
1116 | TREE_OPERAND (offset2, 1)); | |
1117 | ||
1118 | return res; | |
1119 | } | |
1120 | ||
1121 | /* Check if DRA and DRB have equal offsets. */ | |
1122 | bool | |
1123 | dr_equal_offsets_p (struct data_reference *dra, | |
1124 | struct data_reference *drb) | |
1125 | { | |
1126 | tree offset1, offset2; | |
1127 | ||
1128 | offset1 = DR_OFFSET (dra); | |
1129 | offset2 = DR_OFFSET (drb); | |
1130 | ||
1131 | return dr_equal_offsets_p1 (offset1, offset2); | |
1132 | } | |
1133 | ||
87da4f2e | 1134 | /* Returns true if FNA == FNB. */ |
1135 | ||
1136 | static bool | |
1137 | affine_function_equal_p (affine_fn fna, affine_fn fnb) | |
1138 | { | |
f1f41a6c | 1139 | unsigned i, n = fna.length (); |
516849c7 | 1140 | |
f1f41a6c | 1141 | if (n != fnb.length ()) |
de33470d | 1142 | return false; |
bc3c8ad4 | 1143 | |
87da4f2e | 1144 | for (i = 0; i < n; i++) |
f1f41a6c | 1145 | if (!operand_equal_p (fna[i], fnb[i], 0)) |
87da4f2e | 1146 | return false; |
1147 | ||
1148 | return true; | |
1149 | } | |
1150 | ||
1151 | /* If all the functions in CF are the same, returns one of them, | |
1152 | otherwise returns NULL. */ | |
1153 | ||
1154 | static affine_fn | |
1155 | common_affine_function (conflict_function *cf) | |
bc3c8ad4 | 1156 | { |
87da4f2e | 1157 | unsigned i; |
1158 | affine_fn comm; | |
1159 | ||
1160 | if (!CF_NONTRIVIAL_P (cf)) | |
9af5ce0c | 1161 | return affine_fn (); |
87da4f2e | 1162 | |
1163 | comm = cf->fns[0]; | |
1164 | ||
1165 | for (i = 1; i < cf->n; i++) | |
1166 | if (!affine_function_equal_p (comm, cf->fns[i])) | |
9af5ce0c | 1167 | return affine_fn (); |
87da4f2e | 1168 | |
1169 | return comm; | |
1170 | } | |
bc3c8ad4 | 1171 | |
87da4f2e | 1172 | /* Returns the base of the affine function FN. */ |
1173 | ||
1174 | static tree | |
1175 | affine_function_base (affine_fn fn) | |
1176 | { | |
f1f41a6c | 1177 | return fn[0]; |
87da4f2e | 1178 | } |
1179 | ||
1180 | /* Returns true if FN is a constant. */ | |
1181 | ||
1182 | static bool | |
1183 | affine_function_constant_p (affine_fn fn) | |
1184 | { | |
1185 | unsigned i; | |
1186 | tree coef; | |
1187 | ||
f1f41a6c | 1188 | for (i = 1; fn.iterate (i, &coef); i++) |
87da4f2e | 1189 | if (!integer_zerop (coef)) |
f84a688a | 1190 | return false; |
1191 | ||
bc3c8ad4 | 1192 | return true; |
1193 | } | |
1194 | ||
2a21a5df | 1195 | /* Returns true if FN is the zero constant function. */ |
1196 | ||
1197 | static bool | |
1198 | affine_function_zero_p (affine_fn fn) | |
1199 | { | |
1200 | return (integer_zerop (affine_function_base (fn)) | |
1201 | && affine_function_constant_p (fn)); | |
1202 | } | |
1203 | ||
9a3dad1c | 1204 | /* Returns a signed integer type with the largest precision from TA |
1205 | and TB. */ | |
1206 | ||
1207 | static tree | |
1208 | signed_type_for_types (tree ta, tree tb) | |
1209 | { | |
1210 | if (TYPE_PRECISION (ta) > TYPE_PRECISION (tb)) | |
1211 | return signed_type_for (ta); | |
1212 | else | |
1213 | return signed_type_for (tb); | |
1214 | } | |
1215 | ||
87da4f2e | 1216 | /* Applies operation OP on affine functions FNA and FNB, and returns the |
1217 | result. */ | |
1218 | ||
1219 | static affine_fn | |
1220 | affine_fn_op (enum tree_code op, affine_fn fna, affine_fn fnb) | |
1221 | { | |
1222 | unsigned i, n, m; | |
1223 | affine_fn ret; | |
1224 | tree coef; | |
1225 | ||
f1f41a6c | 1226 | if (fnb.length () > fna.length ()) |
87da4f2e | 1227 | { |
f1f41a6c | 1228 | n = fna.length (); |
1229 | m = fnb.length (); | |
87da4f2e | 1230 | } |
1231 | else | |
1232 | { | |
f1f41a6c | 1233 | n = fnb.length (); |
1234 | m = fna.length (); | |
87da4f2e | 1235 | } |
1236 | ||
f1f41a6c | 1237 | ret.create (m); |
87da4f2e | 1238 | for (i = 0; i < n; i++) |
9a3dad1c | 1239 | { |
f1f41a6c | 1240 | tree type = signed_type_for_types (TREE_TYPE (fna[i]), |
1241 | TREE_TYPE (fnb[i])); | |
1242 | ret.quick_push (fold_build2 (op, type, fna[i], fnb[i])); | |
9a3dad1c | 1243 | } |
87da4f2e | 1244 | |
f1f41a6c | 1245 | for (; fna.iterate (i, &coef); i++) |
1246 | ret.quick_push (fold_build2 (op, signed_type_for (TREE_TYPE (coef)), | |
87da4f2e | 1247 | coef, integer_zero_node)); |
f1f41a6c | 1248 | for (; fnb.iterate (i, &coef); i++) |
1249 | ret.quick_push (fold_build2 (op, signed_type_for (TREE_TYPE (coef)), | |
87da4f2e | 1250 | integer_zero_node, coef)); |
1251 | ||
1252 | return ret; | |
1253 | } | |
1254 | ||
1255 | /* Returns the sum of affine functions FNA and FNB. */ | |
1256 | ||
1257 | static affine_fn | |
1258 | affine_fn_plus (affine_fn fna, affine_fn fnb) | |
1259 | { | |
1260 | return affine_fn_op (PLUS_EXPR, fna, fnb); | |
1261 | } | |
1262 | ||
1263 | /* Returns the difference of affine functions FNA and FNB. */ | |
1264 | ||
1265 | static affine_fn | |
1266 | affine_fn_minus (affine_fn fna, affine_fn fnb) | |
1267 | { | |
1268 | return affine_fn_op (MINUS_EXPR, fna, fnb); | |
1269 | } | |
1270 | ||
1271 | /* Frees affine function FN. */ | |
1272 | ||
1273 | static void | |
1274 | affine_fn_free (affine_fn fn) | |
1275 | { | |
f1f41a6c | 1276 | fn.release (); |
87da4f2e | 1277 | } |
1278 | ||
bc3c8ad4 | 1279 | /* Determine for each subscript in the data dependence relation DDR |
1280 | the distance. */ | |
2146e26d | 1281 | |
6b421feb | 1282 | static void |
bc3c8ad4 | 1283 | compute_subscript_distance (struct data_dependence_relation *ddr) |
2146e26d | 1284 | { |
87da4f2e | 1285 | conflict_function *cf_a, *cf_b; |
1286 | affine_fn fn_a, fn_b, diff; | |
1287 | ||
2146e26d | 1288 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
1289 | { | |
1290 | unsigned int i; | |
48e1416a | 1291 | |
2146e26d | 1292 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
1293 | { | |
2146e26d | 1294 | struct subscript *subscript; |
48e1416a | 1295 | |
2146e26d | 1296 | subscript = DDR_SUBSCRIPT (ddr, i); |
87da4f2e | 1297 | cf_a = SUB_CONFLICTS_IN_A (subscript); |
1298 | cf_b = SUB_CONFLICTS_IN_B (subscript); | |
bc3c8ad4 | 1299 | |
87da4f2e | 1300 | fn_a = common_affine_function (cf_a); |
1301 | fn_b = common_affine_function (cf_b); | |
f1f41a6c | 1302 | if (!fn_a.exists () || !fn_b.exists ()) |
bc3c8ad4 | 1303 | { |
87da4f2e | 1304 | SUB_DISTANCE (subscript) = chrec_dont_know; |
1305 | return; | |
bc3c8ad4 | 1306 | } |
87da4f2e | 1307 | diff = affine_fn_minus (fn_a, fn_b); |
48e1416a | 1308 | |
87da4f2e | 1309 | if (affine_function_constant_p (diff)) |
1310 | SUB_DISTANCE (subscript) = affine_function_base (diff); | |
2146e26d | 1311 | else |
1312 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
87da4f2e | 1313 | |
1314 | affine_fn_free (diff); | |
2146e26d | 1315 | } |
1316 | } | |
1317 | } | |
1318 | ||
87da4f2e | 1319 | /* Returns the conflict function for "unknown". */ |
1320 | ||
1321 | static conflict_function * | |
1322 | conflict_fn_not_known (void) | |
1323 | { | |
1324 | conflict_function *fn = XCNEW (conflict_function); | |
1325 | fn->n = NOT_KNOWN; | |
1326 | ||
1327 | return fn; | |
1328 | } | |
1329 | ||
1330 | /* Returns the conflict function for "independent". */ | |
1331 | ||
1332 | static conflict_function * | |
1333 | conflict_fn_no_dependence (void) | |
1334 | { | |
1335 | conflict_function *fn = XCNEW (conflict_function); | |
1336 | fn->n = NO_DEPENDENCE; | |
1337 | ||
1338 | return fn; | |
1339 | } | |
1340 | ||
80bb306a | 1341 | /* Returns true if the address of OBJ is invariant in LOOP. */ |
1342 | ||
1343 | static bool | |
7ecb5bb2 | 1344 | object_address_invariant_in_loop_p (const struct loop *loop, const_tree obj) |
80bb306a | 1345 | { |
1346 | while (handled_component_p (obj)) | |
1347 | { | |
1348 | if (TREE_CODE (obj) == ARRAY_REF) | |
1349 | { | |
1350 | /* Index of the ARRAY_REF was zeroed in analyze_indices, thus we only | |
1351 | need to check the stride and the lower bound of the reference. */ | |
1352 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1353 | loop->num) | |
1354 | || chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 3), | |
1355 | loop->num)) | |
1356 | return false; | |
1357 | } | |
1358 | else if (TREE_CODE (obj) == COMPONENT_REF) | |
1359 | { | |
1360 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1361 | loop->num)) | |
1362 | return false; | |
1363 | } | |
1364 | obj = TREE_OPERAND (obj, 0); | |
1365 | } | |
1366 | ||
182cf5a9 | 1367 | if (!INDIRECT_REF_P (obj) |
1368 | && TREE_CODE (obj) != MEM_REF) | |
80bb306a | 1369 | return true; |
1370 | ||
1371 | return !chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 0), | |
1372 | loop->num); | |
1373 | } | |
1374 | ||
80bb306a | 1375 | /* Returns false if we can prove that data references A and B do not alias, |
5fc88ffd | 1376 | true otherwise. If LOOP_NEST is false no cross-iteration aliases are |
1377 | considered. */ | |
80bb306a | 1378 | |
255b6be7 | 1379 | bool |
5fc88ffd | 1380 | dr_may_alias_p (const struct data_reference *a, const struct data_reference *b, |
1381 | bool loop_nest) | |
80bb306a | 1382 | { |
2760c0e3 | 1383 | tree addr_a = DR_BASE_OBJECT (a); |
1384 | tree addr_b = DR_BASE_OBJECT (b); | |
80bb306a | 1385 | |
5fc88ffd | 1386 | /* If we are not processing a loop nest but scalar code we |
1387 | do not need to care about possible cross-iteration dependences | |
1388 | and thus can process the full original reference. Do so, | |
1389 | similar to how loop invariant motion applies extra offset-based | |
1390 | disambiguation. */ | |
1391 | if (!loop_nest) | |
1392 | { | |
1393 | aff_tree off1, off2; | |
5de9d3ed | 1394 | widest_int size1, size2; |
5fc88ffd | 1395 | get_inner_reference_aff (DR_REF (a), &off1, &size1); |
1396 | get_inner_reference_aff (DR_REF (b), &off2, &size2); | |
e913b5cd | 1397 | aff_combination_scale (&off1, -1); |
5fc88ffd | 1398 | aff_combination_add (&off2, &off1); |
1399 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) | |
1400 | return false; | |
1401 | } | |
1402 | ||
c8efcccb | 1403 | /* If we had an evolution in a pointer-based MEM_REF BASE_OBJECT we |
1404 | do not know the size of the base-object. So we cannot do any | |
1405 | offset/overlap based analysis but have to rely on points-to | |
1406 | information only. */ | |
95539e1d | 1407 | if (TREE_CODE (addr_a) == MEM_REF |
c8efcccb | 1408 | && TREE_CODE (TREE_OPERAND (addr_a, 0)) == SSA_NAME) |
95539e1d | 1409 | { |
c8efcccb | 1410 | /* For true dependences we can apply TBAA. */ |
1411 | if (flag_strict_aliasing | |
1412 | && DR_IS_WRITE (a) && DR_IS_READ (b) | |
1413 | && !alias_sets_conflict_p (get_alias_set (DR_REF (a)), | |
1414 | get_alias_set (DR_REF (b)))) | |
1415 | return false; | |
1416 | if (TREE_CODE (addr_b) == MEM_REF) | |
95539e1d | 1417 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), |
1418 | TREE_OPERAND (addr_b, 0)); | |
1419 | else | |
1420 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), | |
1421 | build_fold_addr_expr (addr_b)); | |
1422 | } | |
1423 | else if (TREE_CODE (addr_b) == MEM_REF | |
c8efcccb | 1424 | && TREE_CODE (TREE_OPERAND (addr_b, 0)) == SSA_NAME) |
1425 | { | |
1426 | /* For true dependences we can apply TBAA. */ | |
1427 | if (flag_strict_aliasing | |
1428 | && DR_IS_WRITE (a) && DR_IS_READ (b) | |
1429 | && !alias_sets_conflict_p (get_alias_set (DR_REF (a)), | |
1430 | get_alias_set (DR_REF (b)))) | |
1431 | return false; | |
1432 | if (TREE_CODE (addr_a) == MEM_REF) | |
1433 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), | |
1434 | TREE_OPERAND (addr_b, 0)); | |
1435 | else | |
1436 | return ptr_derefs_may_alias_p (build_fold_addr_expr (addr_a), | |
1437 | TREE_OPERAND (addr_b, 0)); | |
1438 | } | |
95539e1d | 1439 | |
1440 | /* Otherwise DR_BASE_OBJECT is an access that covers the whole object | |
1441 | that is being subsetted in the loop nest. */ | |
9ff25603 | 1442 | if (DR_IS_WRITE (a) && DR_IS_WRITE (b)) |
2760c0e3 | 1443 | return refs_output_dependent_p (addr_a, addr_b); |
9ff25603 | 1444 | else if (DR_IS_READ (a) && DR_IS_WRITE (b)) |
2760c0e3 | 1445 | return refs_anti_dependent_p (addr_a, addr_b); |
1446 | return refs_may_alias_p (addr_a, addr_b); | |
80bb306a | 1447 | } |
1448 | ||
6b421feb | 1449 | /* Initialize a data dependence relation between data accesses A and |
1450 | B. NB_LOOPS is the number of loops surrounding the references: the | |
1451 | size of the classic distance/direction vectors. */ | |
2146e26d | 1452 | |
16dfb112 | 1453 | struct data_dependence_relation * |
48e1416a | 1454 | initialize_data_dependence_relation (struct data_reference *a, |
6b421feb | 1455 | struct data_reference *b, |
f1f41a6c | 1456 | vec<loop_p> loop_nest) |
2146e26d | 1457 | { |
1458 | struct data_dependence_relation *res; | |
6b421feb | 1459 | unsigned int i; |
48e1416a | 1460 | |
4c36ffe6 | 1461 | res = XNEW (struct data_dependence_relation); |
2146e26d | 1462 | DDR_A (res) = a; |
1463 | DDR_B (res) = b; | |
f1f41a6c | 1464 | DDR_LOOP_NEST (res).create (0); |
0ecb94cf | 1465 | DDR_REVERSED_P (res) = false; |
f1f41a6c | 1466 | DDR_SUBSCRIPTS (res).create (0); |
1467 | DDR_DIR_VECTS (res).create (0); | |
1468 | DDR_DIST_VECTS (res).create (0); | |
2146e26d | 1469 | |
516849c7 | 1470 | if (a == NULL || b == NULL) |
1471 | { | |
48e1416a | 1472 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
516849c7 | 1473 | return res; |
48e1416a | 1474 | } |
516849c7 | 1475 | |
80bb306a | 1476 | /* If the data references do not alias, then they are independent. */ |
f1f41a6c | 1477 | if (!dr_may_alias_p (a, b, loop_nest.exists ())) |
516849c7 | 1478 | { |
48e1416a | 1479 | DDR_ARE_DEPENDENT (res) = chrec_known; |
516849c7 | 1480 | return res; |
1481 | } | |
2146e26d | 1482 | |
cc76857b | 1483 | /* The case where the references are exactly the same. */ |
c127dd86 | 1484 | if (operand_equal_p (DR_REF (a), DR_REF (b), 0)) |
1485 | { | |
f1f41a6c | 1486 | if (loop_nest.exists () |
1487 | && !object_address_invariant_in_loop_p (loop_nest[0], | |
c76b51be | 1488 | DR_BASE_OBJECT (a))) |
1489 | { | |
1490 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1491 | return res; | |
1492 | } | |
c127dd86 | 1493 | DDR_AFFINE_P (res) = true; |
1494 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
f1f41a6c | 1495 | DDR_SUBSCRIPTS (res).create (DR_NUM_DIMENSIONS (a)); |
c127dd86 | 1496 | DDR_LOOP_NEST (res) = loop_nest; |
1497 | DDR_INNER_LOOP (res) = 0; | |
1498 | DDR_SELF_REFERENCE (res) = true; | |
c76b51be | 1499 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1500 | { | |
1501 | struct subscript *subscript; | |
1502 | ||
1503 | subscript = XNEW (struct subscript); | |
1504 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); | |
1505 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
1506 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; | |
1507 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
f1f41a6c | 1508 | DDR_SUBSCRIPTS (res).safe_push (subscript); |
c76b51be | 1509 | } |
c127dd86 | 1510 | return res; |
1511 | } | |
1512 | ||
80bb306a | 1513 | /* If the references do not access the same object, we do not know |
1514 | whether they alias or not. */ | |
1515 | if (!operand_equal_p (DR_BASE_OBJECT (a), DR_BASE_OBJECT (b), 0)) | |
2146e26d | 1516 | { |
48e1416a | 1517 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
516849c7 | 1518 | return res; |
1519 | } | |
6b421feb | 1520 | |
80bb306a | 1521 | /* If the base of the object is not invariant in the loop nest, we cannot |
bef304b8 | 1522 | analyze it. TODO -- in fact, it would suffice to record that there may |
310d2511 | 1523 | be arbitrary dependences in the loops where the base object varies. */ |
f1f41a6c | 1524 | if (loop_nest.exists () |
1525 | && !object_address_invariant_in_loop_p (loop_nest[0], | |
37545e54 | 1526 | DR_BASE_OBJECT (a))) |
516849c7 | 1527 | { |
48e1416a | 1528 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
516849c7 | 1529 | return res; |
1530 | } | |
80bb306a | 1531 | |
fabd4538 | 1532 | /* If the number of dimensions of the access to not agree we can have |
1533 | a pointer access to a component of the array element type and an | |
1534 | array access while the base-objects are still the same. Punt. */ | |
1535 | if (DR_NUM_DIMENSIONS (a) != DR_NUM_DIMENSIONS (b)) | |
1536 | { | |
1537 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1538 | return res; | |
1539 | } | |
80bb306a | 1540 | |
516849c7 | 1541 | DDR_AFFINE_P (res) = true; |
1542 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
f1f41a6c | 1543 | DDR_SUBSCRIPTS (res).create (DR_NUM_DIMENSIONS (a)); |
b44d1046 | 1544 | DDR_LOOP_NEST (res) = loop_nest; |
355572cc | 1545 | DDR_INNER_LOOP (res) = 0; |
c127dd86 | 1546 | DDR_SELF_REFERENCE (res) = false; |
1532ec98 | 1547 | |
516849c7 | 1548 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1549 | { | |
1550 | struct subscript *subscript; | |
48e1416a | 1551 | |
4c36ffe6 | 1552 | subscript = XNEW (struct subscript); |
87da4f2e | 1553 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); |
1554 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
516849c7 | 1555 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
1556 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
f1f41a6c | 1557 | DDR_SUBSCRIPTS (res).safe_push (subscript); |
2146e26d | 1558 | } |
41c7a324 | 1559 | |
2146e26d | 1560 | return res; |
1561 | } | |
1562 | ||
87da4f2e | 1563 | /* Frees memory used by the conflict function F. */ |
1564 | ||
1565 | static void | |
1566 | free_conflict_function (conflict_function *f) | |
1567 | { | |
1568 | unsigned i; | |
1569 | ||
1570 | if (CF_NONTRIVIAL_P (f)) | |
1571 | { | |
1572 | for (i = 0; i < f->n; i++) | |
1573 | affine_fn_free (f->fns[i]); | |
1574 | } | |
1575 | free (f); | |
1576 | } | |
1577 | ||
1578 | /* Frees memory used by SUBSCRIPTS. */ | |
1579 | ||
1580 | static void | |
f1f41a6c | 1581 | free_subscripts (vec<subscript_p> subscripts) |
87da4f2e | 1582 | { |
1583 | unsigned i; | |
1584 | subscript_p s; | |
1585 | ||
f1f41a6c | 1586 | FOR_EACH_VEC_ELT (subscripts, i, s) |
87da4f2e | 1587 | { |
1588 | free_conflict_function (s->conflicting_iterations_in_a); | |
1589 | free_conflict_function (s->conflicting_iterations_in_b); | |
19af51e2 | 1590 | free (s); |
87da4f2e | 1591 | } |
f1f41a6c | 1592 | subscripts.release (); |
87da4f2e | 1593 | } |
1594 | ||
2146e26d | 1595 | /* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap |
1596 | description. */ | |
1597 | ||
1598 | static inline void | |
48e1416a | 1599 | finalize_ddr_dependent (struct data_dependence_relation *ddr, |
2146e26d | 1600 | tree chrec) |
1601 | { | |
48e1416a | 1602 | DDR_ARE_DEPENDENT (ddr) = chrec; |
87da4f2e | 1603 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
f1f41a6c | 1604 | DDR_SUBSCRIPTS (ddr).create (0); |
2146e26d | 1605 | } |
1606 | ||
bc3c8ad4 | 1607 | /* The dependence relation DDR cannot be represented by a distance |
1608 | vector. */ | |
1609 | ||
1610 | static inline void | |
1611 | non_affine_dependence_relation (struct data_dependence_relation *ddr) | |
1612 | { | |
1613 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1614 | fprintf (dump_file, "(Dependence relation cannot be represented by distance vector.) \n"); | |
1615 | ||
1616 | DDR_AFFINE_P (ddr) = false; | |
1617 | } | |
1618 | ||
2146e26d | 1619 | \f |
1620 | ||
1621 | /* This section contains the classic Banerjee tests. */ | |
1622 | ||
1623 | /* Returns true iff CHREC_A and CHREC_B are not dependent on any index | |
1624 | variables, i.e., if the ZIV (Zero Index Variable) test is true. */ | |
1625 | ||
1626 | static inline bool | |
7ecb5bb2 | 1627 | ziv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
2146e26d | 1628 | { |
1629 | return (evolution_function_is_constant_p (chrec_a) | |
1630 | && evolution_function_is_constant_p (chrec_b)); | |
1631 | } | |
1632 | ||
1633 | /* Returns true iff CHREC_A and CHREC_B are dependent on an index | |
1634 | variable, i.e., if the SIV (Single Index Variable) test is true. */ | |
1635 | ||
1636 | static bool | |
7ecb5bb2 | 1637 | siv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
2146e26d | 1638 | { |
1639 | if ((evolution_function_is_constant_p (chrec_a) | |
1640 | && evolution_function_is_univariate_p (chrec_b)) | |
1641 | || (evolution_function_is_constant_p (chrec_b) | |
1642 | && evolution_function_is_univariate_p (chrec_a))) | |
1643 | return true; | |
48e1416a | 1644 | |
2146e26d | 1645 | if (evolution_function_is_univariate_p (chrec_a) |
1646 | && evolution_function_is_univariate_p (chrec_b)) | |
1647 | { | |
1648 | switch (TREE_CODE (chrec_a)) | |
1649 | { | |
1650 | case POLYNOMIAL_CHREC: | |
1651 | switch (TREE_CODE (chrec_b)) | |
1652 | { | |
1653 | case POLYNOMIAL_CHREC: | |
1654 | if (CHREC_VARIABLE (chrec_a) != CHREC_VARIABLE (chrec_b)) | |
1655 | return false; | |
48e1416a | 1656 | |
2146e26d | 1657 | default: |
1658 | return true; | |
1659 | } | |
48e1416a | 1660 | |
2146e26d | 1661 | default: |
1662 | return true; | |
1663 | } | |
1664 | } | |
48e1416a | 1665 | |
2146e26d | 1666 | return false; |
1667 | } | |
1668 | ||
87da4f2e | 1669 | /* Creates a conflict function with N dimensions. The affine functions |
1670 | in each dimension follow. */ | |
1671 | ||
1672 | static conflict_function * | |
1673 | conflict_fn (unsigned n, ...) | |
1674 | { | |
1675 | unsigned i; | |
1676 | conflict_function *ret = XCNEW (conflict_function); | |
1677 | va_list ap; | |
1678 | ||
a86c75a6 | 1679 | gcc_assert (0 < n && n <= MAX_DIM); |
9af5ce0c | 1680 | va_start (ap, n); |
48e1416a | 1681 | |
87da4f2e | 1682 | ret->n = n; |
1683 | for (i = 0; i < n; i++) | |
1684 | ret->fns[i] = va_arg (ap, affine_fn); | |
9af5ce0c | 1685 | va_end (ap); |
87da4f2e | 1686 | |
1687 | return ret; | |
1688 | } | |
1689 | ||
1690 | /* Returns constant affine function with value CST. */ | |
1691 | ||
1692 | static affine_fn | |
1693 | affine_fn_cst (tree cst) | |
1694 | { | |
f1f41a6c | 1695 | affine_fn fn; |
1696 | fn.create (1); | |
1697 | fn.quick_push (cst); | |
87da4f2e | 1698 | return fn; |
1699 | } | |
1700 | ||
1701 | /* Returns affine function with single variable, CST + COEF * x_DIM. */ | |
1702 | ||
1703 | static affine_fn | |
1704 | affine_fn_univar (tree cst, unsigned dim, tree coef) | |
1705 | { | |
f1f41a6c | 1706 | affine_fn fn; |
1707 | fn.create (dim + 1); | |
87da4f2e | 1708 | unsigned i; |
1709 | ||
1710 | gcc_assert (dim > 0); | |
f1f41a6c | 1711 | fn.quick_push (cst); |
87da4f2e | 1712 | for (i = 1; i < dim; i++) |
f1f41a6c | 1713 | fn.quick_push (integer_zero_node); |
1714 | fn.quick_push (coef); | |
87da4f2e | 1715 | return fn; |
1716 | } | |
1717 | ||
2146e26d | 1718 | /* Analyze a ZIV (Zero Index Variable) subscript. *OVERLAPS_A and |
1719 | *OVERLAPS_B are initialized to the functions that describe the | |
1720 | relation between the elements accessed twice by CHREC_A and | |
1721 | CHREC_B. For k >= 0, the following property is verified: | |
1722 | ||
1723 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1724 | ||
48e1416a | 1725 | static void |
1726 | analyze_ziv_subscript (tree chrec_a, | |
1727 | tree chrec_b, | |
87da4f2e | 1728 | conflict_function **overlaps_a, |
48e1416a | 1729 | conflict_function **overlaps_b, |
bc3c8ad4 | 1730 | tree *last_conflicts) |
2146e26d | 1731 | { |
9a3dad1c | 1732 | tree type, difference; |
6b421feb | 1733 | dependence_stats.num_ziv++; |
48e1416a | 1734 | |
2146e26d | 1735 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1736 | fprintf (dump_file, "(analyze_ziv_subscript \n"); | |
9a3dad1c | 1737 | |
1738 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); | |
75a70cf9 | 1739 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1740 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
9a3dad1c | 1741 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
48e1416a | 1742 | |
2146e26d | 1743 | switch (TREE_CODE (difference)) |
1744 | { | |
1745 | case INTEGER_CST: | |
1746 | if (integer_zerop (difference)) | |
1747 | { | |
1748 | /* The difference is equal to zero: the accessed index | |
1749 | overlaps for each iteration in the loop. */ | |
87da4f2e | 1750 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
1751 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
bc3c8ad4 | 1752 | *last_conflicts = chrec_dont_know; |
6b421feb | 1753 | dependence_stats.num_ziv_dependent++; |
2146e26d | 1754 | } |
1755 | else | |
1756 | { | |
1757 | /* The accesses do not overlap. */ | |
87da4f2e | 1758 | *overlaps_a = conflict_fn_no_dependence (); |
1759 | *overlaps_b = conflict_fn_no_dependence (); | |
bc3c8ad4 | 1760 | *last_conflicts = integer_zero_node; |
6b421feb | 1761 | dependence_stats.num_ziv_independent++; |
2146e26d | 1762 | } |
1763 | break; | |
48e1416a | 1764 | |
2146e26d | 1765 | default: |
48e1416a | 1766 | /* We're not sure whether the indexes overlap. For the moment, |
2146e26d | 1767 | conservatively answer "don't know". */ |
6b421feb | 1768 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1769 | fprintf (dump_file, "ziv test failed: difference is non-integer.\n"); | |
1770 | ||
87da4f2e | 1771 | *overlaps_a = conflict_fn_not_known (); |
1772 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 1773 | *last_conflicts = chrec_dont_know; |
6b421feb | 1774 | dependence_stats.num_ziv_unimplemented++; |
2146e26d | 1775 | break; |
1776 | } | |
48e1416a | 1777 | |
2146e26d | 1778 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1779 | fprintf (dump_file, ")\n"); | |
1780 | } | |
1781 | ||
8fe79ba5 | 1782 | /* Similar to max_stmt_executions_int, but returns the bound as a tree, |
d500fef3 | 1783 | and only if it fits to the int type. If this is not the case, or the |
8fe79ba5 | 1784 | bound on the number of iterations of LOOP could not be derived, returns |
d500fef3 | 1785 | chrec_dont_know. */ |
1786 | ||
1787 | static tree | |
8fe79ba5 | 1788 | max_stmt_executions_tree (struct loop *loop) |
d500fef3 | 1789 | { |
5de9d3ed | 1790 | widest_int nit; |
d500fef3 | 1791 | |
fee017b3 | 1792 | if (!max_stmt_executions (loop, &nit)) |
d500fef3 | 1793 | return chrec_dont_know; |
1794 | ||
796b6678 | 1795 | if (!wi::fits_to_tree_p (nit, unsigned_type_node)) |
d500fef3 | 1796 | return chrec_dont_know; |
1797 | ||
e913b5cd | 1798 | return wide_int_to_tree (unsigned_type_node, nit); |
d500fef3 | 1799 | } |
1800 | ||
06a9142d | 1801 | /* Determine whether the CHREC is always positive/negative. If the expression |
1802 | cannot be statically analyzed, return false, otherwise set the answer into | |
1803 | VALUE. */ | |
1804 | ||
1805 | static bool | |
1806 | chrec_is_positive (tree chrec, bool *value) | |
1807 | { | |
1808 | bool value0, value1, value2; | |
1809 | tree end_value, nb_iter; | |
1810 | ||
1811 | switch (TREE_CODE (chrec)) | |
1812 | { | |
1813 | case POLYNOMIAL_CHREC: | |
1814 | if (!chrec_is_positive (CHREC_LEFT (chrec), &value0) | |
1815 | || !chrec_is_positive (CHREC_RIGHT (chrec), &value1)) | |
1816 | return false; | |
1817 | ||
1818 | /* FIXME -- overflows. */ | |
1819 | if (value0 == value1) | |
1820 | { | |
1821 | *value = value0; | |
1822 | return true; | |
1823 | } | |
1824 | ||
1825 | /* Otherwise the chrec is under the form: "{-197, +, 2}_1", | |
1826 | and the proof consists in showing that the sign never | |
1827 | changes during the execution of the loop, from 0 to | |
1828 | loop->nb_iterations. */ | |
1829 | if (!evolution_function_is_affine_p (chrec)) | |
1830 | return false; | |
1831 | ||
1832 | nb_iter = number_of_latch_executions (get_chrec_loop (chrec)); | |
1833 | if (chrec_contains_undetermined (nb_iter)) | |
1834 | return false; | |
1835 | ||
1836 | #if 0 | |
1837 | /* TODO -- If the test is after the exit, we may decrease the number of | |
1838 | iterations by one. */ | |
1839 | if (after_exit) | |
1840 | nb_iter = chrec_fold_minus (type, nb_iter, build_int_cst (type, 1)); | |
1841 | #endif | |
1842 | ||
1843 | end_value = chrec_apply (CHREC_VARIABLE (chrec), chrec, nb_iter); | |
1844 | ||
1845 | if (!chrec_is_positive (end_value, &value2)) | |
1846 | return false; | |
1847 | ||
1848 | *value = value0; | |
1849 | return value0 == value1; | |
1850 | ||
1851 | case INTEGER_CST: | |
1852 | switch (tree_int_cst_sgn (chrec)) | |
1853 | { | |
1854 | case -1: | |
1855 | *value = false; | |
1856 | break; | |
1857 | case 1: | |
1858 | *value = true; | |
1859 | break; | |
1860 | default: | |
1861 | return false; | |
1862 | } | |
1863 | return true; | |
1864 | ||
1865 | default: | |
1866 | return false; | |
1867 | } | |
1868 | } | |
1869 | ||
1870 | ||
2146e26d | 1871 | /* Analyze a SIV (Single Index Variable) subscript where CHREC_A is a |
1872 | constant, and CHREC_B is an affine function. *OVERLAPS_A and | |
1873 | *OVERLAPS_B are initialized to the functions that describe the | |
1874 | relation between the elements accessed twice by CHREC_A and | |
1875 | CHREC_B. For k >= 0, the following property is verified: | |
1876 | ||
1877 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1878 | ||
1879 | static void | |
48e1416a | 1880 | analyze_siv_subscript_cst_affine (tree chrec_a, |
2146e26d | 1881 | tree chrec_b, |
48e1416a | 1882 | conflict_function **overlaps_a, |
1883 | conflict_function **overlaps_b, | |
bc3c8ad4 | 1884 | tree *last_conflicts) |
2146e26d | 1885 | { |
1886 | bool value0, value1, value2; | |
9a3dad1c | 1887 | tree type, difference, tmp; |
f84a688a | 1888 | |
9a3dad1c | 1889 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
75a70cf9 | 1890 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1891 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
9a3dad1c | 1892 | difference = chrec_fold_minus (type, initial_condition (chrec_b), chrec_a); |
48e1416a | 1893 | |
06a9142d | 1894 | /* Special case overlap in the first iteration. */ |
1895 | if (integer_zerop (difference)) | |
1896 | { | |
1897 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
1898 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
1899 | *last_conflicts = integer_one_node; | |
1900 | return; | |
1901 | } | |
1902 | ||
2146e26d | 1903 | if (!chrec_is_positive (initial_condition (difference), &value0)) |
1904 | { | |
6b421feb | 1905 | if (dump_file && (dump_flags & TDF_DETAILS)) |
48e1416a | 1906 | fprintf (dump_file, "siv test failed: chrec is not positive.\n"); |
6b421feb | 1907 | |
1908 | dependence_stats.num_siv_unimplemented++; | |
87da4f2e | 1909 | *overlaps_a = conflict_fn_not_known (); |
1910 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 1911 | *last_conflicts = chrec_dont_know; |
2146e26d | 1912 | return; |
1913 | } | |
1914 | else | |
1915 | { | |
1916 | if (value0 == false) | |
1917 | { | |
1918 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value1)) | |
1919 | { | |
6b421feb | 1920 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1921 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1922 | ||
87da4f2e | 1923 | *overlaps_a = conflict_fn_not_known (); |
48e1416a | 1924 | *overlaps_b = conflict_fn_not_known (); |
bc3c8ad4 | 1925 | *last_conflicts = chrec_dont_know; |
6b421feb | 1926 | dependence_stats.num_siv_unimplemented++; |
2146e26d | 1927 | return; |
1928 | } | |
1929 | else | |
1930 | { | |
1931 | if (value1 == true) | |
1932 | { | |
48e1416a | 1933 | /* Example: |
2146e26d | 1934 | chrec_a = 12 |
1935 | chrec_b = {10, +, 1} | |
1936 | */ | |
48e1416a | 1937 | |
e7be49a3 | 1938 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
2146e26d | 1939 | { |
d500fef3 | 1940 | HOST_WIDE_INT numiter; |
1941 | struct loop *loop = get_chrec_loop (chrec_b); | |
b6d41046 | 1942 | |
87da4f2e | 1943 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
9a3dad1c | 1944 | tmp = fold_build2 (EXACT_DIV_EXPR, type, |
1945 | fold_build1 (ABS_EXPR, type, difference), | |
87da4f2e | 1946 | CHREC_RIGHT (chrec_b)); |
1947 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
bc3c8ad4 | 1948 | *last_conflicts = integer_one_node; |
48e1416a | 1949 | |
b6d41046 | 1950 | |
1951 | /* Perform weak-zero siv test to see if overlap is | |
1952 | outside the loop bounds. */ | |
fee017b3 | 1953 | numiter = max_stmt_executions_int (loop); |
b6d41046 | 1954 | |
d500fef3 | 1955 | if (numiter >= 0 |
1956 | && compare_tree_int (tmp, numiter) > 0) | |
b6d41046 | 1957 | { |
87da4f2e | 1958 | free_conflict_function (*overlaps_a); |
1959 | free_conflict_function (*overlaps_b); | |
1960 | *overlaps_a = conflict_fn_no_dependence (); | |
1961 | *overlaps_b = conflict_fn_no_dependence (); | |
b6d41046 | 1962 | *last_conflicts = integer_zero_node; |
6b421feb | 1963 | dependence_stats.num_siv_independent++; |
b6d41046 | 1964 | return; |
48e1416a | 1965 | } |
6b421feb | 1966 | dependence_stats.num_siv_dependent++; |
2146e26d | 1967 | return; |
1968 | } | |
48e1416a | 1969 | |
e7be49a3 | 1970 | /* When the step does not divide the difference, there are |
2146e26d | 1971 | no overlaps. */ |
1972 | else | |
1973 | { | |
87da4f2e | 1974 | *overlaps_a = conflict_fn_no_dependence (); |
48e1416a | 1975 | *overlaps_b = conflict_fn_no_dependence (); |
bc3c8ad4 | 1976 | *last_conflicts = integer_zero_node; |
6b421feb | 1977 | dependence_stats.num_siv_independent++; |
2146e26d | 1978 | return; |
1979 | } | |
1980 | } | |
48e1416a | 1981 | |
2146e26d | 1982 | else |
1983 | { | |
48e1416a | 1984 | /* Example: |
2146e26d | 1985 | chrec_a = 12 |
1986 | chrec_b = {10, +, -1} | |
48e1416a | 1987 | |
2146e26d | 1988 | In this case, chrec_a will not overlap with chrec_b. */ |
87da4f2e | 1989 | *overlaps_a = conflict_fn_no_dependence (); |
1990 | *overlaps_b = conflict_fn_no_dependence (); | |
bc3c8ad4 | 1991 | *last_conflicts = integer_zero_node; |
6b421feb | 1992 | dependence_stats.num_siv_independent++; |
2146e26d | 1993 | return; |
1994 | } | |
1995 | } | |
1996 | } | |
48e1416a | 1997 | else |
2146e26d | 1998 | { |
1999 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value2)) | |
2000 | { | |
6b421feb | 2001 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2002 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
2003 | ||
87da4f2e | 2004 | *overlaps_a = conflict_fn_not_known (); |
48e1416a | 2005 | *overlaps_b = conflict_fn_not_known (); |
bc3c8ad4 | 2006 | *last_conflicts = chrec_dont_know; |
6b421feb | 2007 | dependence_stats.num_siv_unimplemented++; |
2146e26d | 2008 | return; |
2009 | } | |
2010 | else | |
2011 | { | |
2012 | if (value2 == false) | |
2013 | { | |
48e1416a | 2014 | /* Example: |
2146e26d | 2015 | chrec_a = 3 |
2016 | chrec_b = {10, +, -1} | |
2017 | */ | |
e7be49a3 | 2018 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
2146e26d | 2019 | { |
d500fef3 | 2020 | HOST_WIDE_INT numiter; |
2021 | struct loop *loop = get_chrec_loop (chrec_b); | |
b6d41046 | 2022 | |
87da4f2e | 2023 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
9a3dad1c | 2024 | tmp = fold_build2 (EXACT_DIV_EXPR, type, difference, |
87da4f2e | 2025 | CHREC_RIGHT (chrec_b)); |
2026 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
bc3c8ad4 | 2027 | *last_conflicts = integer_one_node; |
b6d41046 | 2028 | |
2029 | /* Perform weak-zero siv test to see if overlap is | |
2030 | outside the loop bounds. */ | |
fee017b3 | 2031 | numiter = max_stmt_executions_int (loop); |
b6d41046 | 2032 | |
d500fef3 | 2033 | if (numiter >= 0 |
2034 | && compare_tree_int (tmp, numiter) > 0) | |
b6d41046 | 2035 | { |
87da4f2e | 2036 | free_conflict_function (*overlaps_a); |
2037 | free_conflict_function (*overlaps_b); | |
2038 | *overlaps_a = conflict_fn_no_dependence (); | |
2039 | *overlaps_b = conflict_fn_no_dependence (); | |
b6d41046 | 2040 | *last_conflicts = integer_zero_node; |
6b421feb | 2041 | dependence_stats.num_siv_independent++; |
b6d41046 | 2042 | return; |
48e1416a | 2043 | } |
6b421feb | 2044 | dependence_stats.num_siv_dependent++; |
2146e26d | 2045 | return; |
2046 | } | |
48e1416a | 2047 | |
c4243fe7 | 2048 | /* When the step does not divide the difference, there |
2146e26d | 2049 | are no overlaps. */ |
2050 | else | |
2051 | { | |
87da4f2e | 2052 | *overlaps_a = conflict_fn_no_dependence (); |
48e1416a | 2053 | *overlaps_b = conflict_fn_no_dependence (); |
bc3c8ad4 | 2054 | *last_conflicts = integer_zero_node; |
6b421feb | 2055 | dependence_stats.num_siv_independent++; |
2146e26d | 2056 | return; |
2057 | } | |
2058 | } | |
2059 | else | |
2060 | { | |
48e1416a | 2061 | /* Example: |
2062 | chrec_a = 3 | |
2146e26d | 2063 | chrec_b = {4, +, 1} |
48e1416a | 2064 | |
2146e26d | 2065 | In this case, chrec_a will not overlap with chrec_b. */ |
87da4f2e | 2066 | *overlaps_a = conflict_fn_no_dependence (); |
2067 | *overlaps_b = conflict_fn_no_dependence (); | |
bc3c8ad4 | 2068 | *last_conflicts = integer_zero_node; |
6b421feb | 2069 | dependence_stats.num_siv_independent++; |
2146e26d | 2070 | return; |
2071 | } | |
2072 | } | |
2073 | } | |
2074 | } | |
2075 | } | |
2076 | ||
fbd828d4 | 2077 | /* Helper recursive function for initializing the matrix A. Returns |
bc3c8ad4 | 2078 | the initial value of CHREC. */ |
2146e26d | 2079 | |
8ceddf57 | 2080 | static tree |
bc3c8ad4 | 2081 | initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) |
2082 | { | |
2083 | gcc_assert (chrec); | |
2084 | ||
8ceddf57 | 2085 | switch (TREE_CODE (chrec)) |
2086 | { | |
2087 | case POLYNOMIAL_CHREC: | |
2088 | gcc_assert (TREE_CODE (CHREC_RIGHT (chrec)) == INTEGER_CST); | |
2089 | ||
2090 | A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); | |
2091 | return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); | |
2092 | ||
2093 | case PLUS_EXPR: | |
2094 | case MULT_EXPR: | |
2095 | case MINUS_EXPR: | |
2096 | { | |
2097 | tree op0 = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
2098 | tree op1 = initialize_matrix_A (A, TREE_OPERAND (chrec, 1), index, mult); | |
2099 | ||
2100 | return chrec_fold_op (TREE_CODE (chrec), chrec_type (chrec), op0, op1); | |
2101 | } | |
2102 | ||
2103 | case NOP_EXPR: | |
2104 | { | |
2105 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
75a70cf9 | 2106 | return chrec_convert (chrec_type (chrec), op, NULL); |
8ceddf57 | 2107 | } |
2108 | ||
b6eab06c | 2109 | case BIT_NOT_EXPR: |
2110 | { | |
2111 | /* Handle ~X as -1 - X. */ | |
2112 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
2113 | return chrec_fold_op (MINUS_EXPR, chrec_type (chrec), | |
2114 | build_int_cst (TREE_TYPE (chrec), -1), op); | |
2115 | } | |
2116 | ||
8ceddf57 | 2117 | case INTEGER_CST: |
2118 | return chrec; | |
c782188f | 2119 | |
8ceddf57 | 2120 | default: |
2121 | gcc_unreachable (); | |
2122 | return NULL_TREE; | |
2123 | } | |
bc3c8ad4 | 2124 | } |
2125 | ||
2126 | #define FLOOR_DIV(x,y) ((x) / (y)) | |
2127 | ||
48e1416a | 2128 | /* Solves the special case of the Diophantine equation: |
bc3c8ad4 | 2129 | | {0, +, STEP_A}_x (OVERLAPS_A) = {0, +, STEP_B}_y (OVERLAPS_B) |
2130 | ||
2131 | Computes the descriptions OVERLAPS_A and OVERLAPS_B. NITER is the | |
2132 | number of iterations that loops X and Y run. The overlaps will be | |
2133 | constructed as evolutions in dimension DIM. */ | |
2146e26d | 2134 | |
2135 | static void | |
48e1416a | 2136 | compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b, |
87da4f2e | 2137 | affine_fn *overlaps_a, |
48e1416a | 2138 | affine_fn *overlaps_b, |
bc3c8ad4 | 2139 | tree *last_conflicts, int dim) |
2140 | { | |
2141 | if (((step_a > 0 && step_b > 0) | |
2142 | || (step_a < 0 && step_b < 0))) | |
2143 | { | |
2144 | int step_overlaps_a, step_overlaps_b; | |
2145 | int gcd_steps_a_b, last_conflict, tau2; | |
2146 | ||
2147 | gcd_steps_a_b = gcd (step_a, step_b); | |
2148 | step_overlaps_a = step_b / gcd_steps_a_b; | |
2149 | step_overlaps_b = step_a / gcd_steps_a_b; | |
2150 | ||
e781c550 | 2151 | if (niter > 0) |
2152 | { | |
2153 | tau2 = FLOOR_DIV (niter, step_overlaps_a); | |
2154 | tau2 = MIN (tau2, FLOOR_DIV (niter, step_overlaps_b)); | |
2155 | last_conflict = tau2; | |
2156 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); | |
2157 | } | |
2158 | else | |
2159 | *last_conflicts = chrec_dont_know; | |
bc3c8ad4 | 2160 | |
48e1416a | 2161 | *overlaps_a = affine_fn_univar (integer_zero_node, dim, |
87da4f2e | 2162 | build_int_cst (NULL_TREE, |
2163 | step_overlaps_a)); | |
48e1416a | 2164 | *overlaps_b = affine_fn_univar (integer_zero_node, dim, |
2165 | build_int_cst (NULL_TREE, | |
87da4f2e | 2166 | step_overlaps_b)); |
bc3c8ad4 | 2167 | } |
2168 | ||
2169 | else | |
2170 | { | |
87da4f2e | 2171 | *overlaps_a = affine_fn_cst (integer_zero_node); |
2172 | *overlaps_b = affine_fn_cst (integer_zero_node); | |
bc3c8ad4 | 2173 | *last_conflicts = integer_zero_node; |
2174 | } | |
2175 | } | |
2176 | ||
bc3c8ad4 | 2177 | /* Solves the special case of a Diophantine equation where CHREC_A is |
2178 | an affine bivariate function, and CHREC_B is an affine univariate | |
48e1416a | 2179 | function. For example, |
bc3c8ad4 | 2180 | |
2181 | | {{0, +, 1}_x, +, 1335}_y = {0, +, 1336}_z | |
48e1416a | 2182 | |
2183 | has the following overlapping functions: | |
bc3c8ad4 | 2184 | |
2185 | | x (t, u, v) = {{0, +, 1336}_t, +, 1}_v | |
2186 | | y (t, u, v) = {{0, +, 1336}_u, +, 1}_v | |
2187 | | z (t, u, v) = {{{0, +, 1}_t, +, 1335}_u, +, 1}_v | |
2188 | ||
0975351b | 2189 | FORNOW: This is a specialized implementation for a case occurring in |
bc3c8ad4 | 2190 | a common benchmark. Implement the general algorithm. */ |
2191 | ||
2192 | static void | |
48e1416a | 2193 | compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b, |
87da4f2e | 2194 | conflict_function **overlaps_a, |
48e1416a | 2195 | conflict_function **overlaps_b, |
bc3c8ad4 | 2196 | tree *last_conflicts) |
2146e26d | 2197 | { |
bc3c8ad4 | 2198 | bool xz_p, yz_p, xyz_p; |
2199 | int step_x, step_y, step_z; | |
d500fef3 | 2200 | HOST_WIDE_INT niter_x, niter_y, niter_z, niter; |
87da4f2e | 2201 | affine_fn overlaps_a_xz, overlaps_b_xz; |
2202 | affine_fn overlaps_a_yz, overlaps_b_yz; | |
2203 | affine_fn overlaps_a_xyz, overlaps_b_xyz; | |
2204 | affine_fn ova1, ova2, ovb; | |
2205 | tree last_conflicts_xz, last_conflicts_yz, last_conflicts_xyz; | |
bc3c8ad4 | 2206 | |
58f77a87 | 2207 | step_x = int_cst_value (CHREC_RIGHT (CHREC_LEFT (chrec_a))); |
2208 | step_y = int_cst_value (CHREC_RIGHT (chrec_a)); | |
2209 | step_z = int_cst_value (CHREC_RIGHT (chrec_b)); | |
bc3c8ad4 | 2210 | |
fee017b3 | 2211 | niter_x = max_stmt_executions_int (get_chrec_loop (CHREC_LEFT (chrec_a))); |
2212 | niter_y = max_stmt_executions_int (get_chrec_loop (chrec_a)); | |
2213 | niter_z = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
48e1416a | 2214 | |
d500fef3 | 2215 | if (niter_x < 0 || niter_y < 0 || niter_z < 0) |
bc3c8ad4 | 2216 | { |
6b421feb | 2217 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2218 | fprintf (dump_file, "overlap steps test failed: no iteration counts.\n"); | |
48e1416a | 2219 | |
87da4f2e | 2220 | *overlaps_a = conflict_fn_not_known (); |
2221 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 2222 | *last_conflicts = chrec_dont_know; |
2223 | return; | |
2224 | } | |
2225 | ||
bc3c8ad4 | 2226 | niter = MIN (niter_x, niter_z); |
2227 | compute_overlap_steps_for_affine_univar (niter, step_x, step_z, | |
2228 | &overlaps_a_xz, | |
2229 | &overlaps_b_xz, | |
2230 | &last_conflicts_xz, 1); | |
2231 | niter = MIN (niter_y, niter_z); | |
2232 | compute_overlap_steps_for_affine_univar (niter, step_y, step_z, | |
2233 | &overlaps_a_yz, | |
2234 | &overlaps_b_yz, | |
2235 | &last_conflicts_yz, 2); | |
2236 | niter = MIN (niter_x, niter_z); | |
2237 | niter = MIN (niter_y, niter); | |
2238 | compute_overlap_steps_for_affine_univar (niter, step_x + step_y, step_z, | |
2239 | &overlaps_a_xyz, | |
2240 | &overlaps_b_xyz, | |
2241 | &last_conflicts_xyz, 3); | |
2242 | ||
2243 | xz_p = !integer_zerop (last_conflicts_xz); | |
2244 | yz_p = !integer_zerop (last_conflicts_yz); | |
2245 | xyz_p = !integer_zerop (last_conflicts_xyz); | |
2246 | ||
2247 | if (xz_p || yz_p || xyz_p) | |
2248 | { | |
87da4f2e | 2249 | ova1 = affine_fn_cst (integer_zero_node); |
2250 | ova2 = affine_fn_cst (integer_zero_node); | |
2251 | ovb = affine_fn_cst (integer_zero_node); | |
bc3c8ad4 | 2252 | if (xz_p) |
2253 | { | |
87da4f2e | 2254 | affine_fn t0 = ova1; |
2255 | affine_fn t2 = ovb; | |
2256 | ||
2257 | ova1 = affine_fn_plus (ova1, overlaps_a_xz); | |
2258 | ovb = affine_fn_plus (ovb, overlaps_b_xz); | |
2259 | affine_fn_free (t0); | |
2260 | affine_fn_free (t2); | |
bc3c8ad4 | 2261 | *last_conflicts = last_conflicts_xz; |
2262 | } | |
2263 | if (yz_p) | |
2264 | { | |
87da4f2e | 2265 | affine_fn t0 = ova2; |
2266 | affine_fn t2 = ovb; | |
2267 | ||
2268 | ova2 = affine_fn_plus (ova2, overlaps_a_yz); | |
2269 | ovb = affine_fn_plus (ovb, overlaps_b_yz); | |
2270 | affine_fn_free (t0); | |
2271 | affine_fn_free (t2); | |
bc3c8ad4 | 2272 | *last_conflicts = last_conflicts_yz; |
2273 | } | |
2274 | if (xyz_p) | |
2275 | { | |
87da4f2e | 2276 | affine_fn t0 = ova1; |
2277 | affine_fn t2 = ova2; | |
2278 | affine_fn t4 = ovb; | |
2279 | ||
2280 | ova1 = affine_fn_plus (ova1, overlaps_a_xyz); | |
2281 | ova2 = affine_fn_plus (ova2, overlaps_a_xyz); | |
2282 | ovb = affine_fn_plus (ovb, overlaps_b_xyz); | |
2283 | affine_fn_free (t0); | |
2284 | affine_fn_free (t2); | |
2285 | affine_fn_free (t4); | |
bc3c8ad4 | 2286 | *last_conflicts = last_conflicts_xyz; |
2287 | } | |
87da4f2e | 2288 | *overlaps_a = conflict_fn (2, ova1, ova2); |
2289 | *overlaps_b = conflict_fn (1, ovb); | |
bc3c8ad4 | 2290 | } |
2291 | else | |
2292 | { | |
87da4f2e | 2293 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2294 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
bc3c8ad4 | 2295 | *last_conflicts = integer_zero_node; |
2296 | } | |
87da4f2e | 2297 | |
2298 | affine_fn_free (overlaps_a_xz); | |
2299 | affine_fn_free (overlaps_b_xz); | |
2300 | affine_fn_free (overlaps_a_yz); | |
2301 | affine_fn_free (overlaps_b_yz); | |
2302 | affine_fn_free (overlaps_a_xyz); | |
2303 | affine_fn_free (overlaps_b_xyz); | |
2146e26d | 2304 | } |
2305 | ||
e01f9f1f | 2306 | /* Copy the elements of vector VEC1 with length SIZE to VEC2. */ |
2307 | ||
2308 | static void | |
2309 | lambda_vector_copy (lambda_vector vec1, lambda_vector vec2, | |
2310 | int size) | |
2311 | { | |
2312 | memcpy (vec2, vec1, size * sizeof (*vec1)); | |
2313 | } | |
2314 | ||
2315 | /* Copy the elements of M x N matrix MAT1 to MAT2. */ | |
2316 | ||
2317 | static void | |
2318 | lambda_matrix_copy (lambda_matrix mat1, lambda_matrix mat2, | |
2319 | int m, int n) | |
2320 | { | |
2321 | int i; | |
2322 | ||
2323 | for (i = 0; i < m; i++) | |
2324 | lambda_vector_copy (mat1[i], mat2[i], n); | |
2325 | } | |
2326 | ||
2327 | /* Store the N x N identity matrix in MAT. */ | |
2328 | ||
2329 | static void | |
2330 | lambda_matrix_id (lambda_matrix mat, int size) | |
2331 | { | |
2332 | int i, j; | |
2333 | ||
2334 | for (i = 0; i < size; i++) | |
2335 | for (j = 0; j < size; j++) | |
2336 | mat[i][j] = (i == j) ? 1 : 0; | |
2337 | } | |
2338 | ||
2339 | /* Return the first nonzero element of vector VEC1 between START and N. | |
2340 | We must have START <= N. Returns N if VEC1 is the zero vector. */ | |
2341 | ||
2342 | static int | |
2343 | lambda_vector_first_nz (lambda_vector vec1, int n, int start) | |
2344 | { | |
2345 | int j = start; | |
2346 | while (j < n && vec1[j] == 0) | |
2347 | j++; | |
2348 | return j; | |
2349 | } | |
2350 | ||
2351 | /* Add a multiple of row R1 of matrix MAT with N columns to row R2: | |
2352 | R2 = R2 + CONST1 * R1. */ | |
2353 | ||
2354 | static void | |
2355 | lambda_matrix_row_add (lambda_matrix mat, int n, int r1, int r2, int const1) | |
2356 | { | |
2357 | int i; | |
2358 | ||
2359 | if (const1 == 0) | |
2360 | return; | |
2361 | ||
2362 | for (i = 0; i < n; i++) | |
2363 | mat[r2][i] += const1 * mat[r1][i]; | |
2364 | } | |
2365 | ||
2366 | /* Swap rows R1 and R2 in matrix MAT. */ | |
2367 | ||
2368 | static void | |
2369 | lambda_matrix_row_exchange (lambda_matrix mat, int r1, int r2) | |
2370 | { | |
2371 | lambda_vector row; | |
2372 | ||
2373 | row = mat[r1]; | |
2374 | mat[r1] = mat[r2]; | |
2375 | mat[r2] = row; | |
2376 | } | |
2377 | ||
2378 | /* Multiply vector VEC1 of length SIZE by a constant CONST1, | |
2379 | and store the result in VEC2. */ | |
2380 | ||
2381 | static void | |
2382 | lambda_vector_mult_const (lambda_vector vec1, lambda_vector vec2, | |
2383 | int size, int const1) | |
2384 | { | |
2385 | int i; | |
2386 | ||
2387 | if (const1 == 0) | |
2388 | lambda_vector_clear (vec2, size); | |
2389 | else | |
2390 | for (i = 0; i < size; i++) | |
2391 | vec2[i] = const1 * vec1[i]; | |
2392 | } | |
2393 | ||
2394 | /* Negate vector VEC1 with length SIZE and store it in VEC2. */ | |
2395 | ||
2396 | static void | |
2397 | lambda_vector_negate (lambda_vector vec1, lambda_vector vec2, | |
2398 | int size) | |
2399 | { | |
2400 | lambda_vector_mult_const (vec1, vec2, size, -1); | |
2401 | } | |
2402 | ||
2403 | /* Negate row R1 of matrix MAT which has N columns. */ | |
2404 | ||
2405 | static void | |
2406 | lambda_matrix_row_negate (lambda_matrix mat, int n, int r1) | |
2407 | { | |
2408 | lambda_vector_negate (mat[r1], mat[r1], n); | |
2409 | } | |
2410 | ||
2411 | /* Return true if two vectors are equal. */ | |
2412 | ||
2413 | static bool | |
2414 | lambda_vector_equal (lambda_vector vec1, lambda_vector vec2, int size) | |
2415 | { | |
2416 | int i; | |
2417 | for (i = 0; i < size; i++) | |
2418 | if (vec1[i] != vec2[i]) | |
2419 | return false; | |
2420 | return true; | |
2421 | } | |
2422 | ||
2423 | /* Given an M x N integer matrix A, this function determines an M x | |
2424 | M unimodular matrix U, and an M x N echelon matrix S such that | |
2425 | "U.A = S". This decomposition is also known as "right Hermite". | |
2426 | ||
2427 | Ref: Algorithm 2.1 page 33 in "Loop Transformations for | |
2428 | Restructuring Compilers" Utpal Banerjee. */ | |
2429 | ||
2430 | static void | |
2431 | lambda_matrix_right_hermite (lambda_matrix A, int m, int n, | |
2432 | lambda_matrix S, lambda_matrix U) | |
2433 | { | |
2434 | int i, j, i0 = 0; | |
2435 | ||
2436 | lambda_matrix_copy (A, S, m, n); | |
2437 | lambda_matrix_id (U, m); | |
2438 | ||
2439 | for (j = 0; j < n; j++) | |
2440 | { | |
2441 | if (lambda_vector_first_nz (S[j], m, i0) < m) | |
2442 | { | |
2443 | ++i0; | |
2444 | for (i = m - 1; i >= i0; i--) | |
2445 | { | |
2446 | while (S[i][j] != 0) | |
2447 | { | |
2448 | int sigma, factor, a, b; | |
2449 | ||
2450 | a = S[i-1][j]; | |
2451 | b = S[i][j]; | |
2452 | sigma = (a * b < 0) ? -1: 1; | |
2453 | a = abs (a); | |
2454 | b = abs (b); | |
2455 | factor = sigma * (a / b); | |
2456 | ||
2457 | lambda_matrix_row_add (S, n, i, i-1, -factor); | |
2458 | lambda_matrix_row_exchange (S, i, i-1); | |
2459 | ||
2460 | lambda_matrix_row_add (U, m, i, i-1, -factor); | |
2461 | lambda_matrix_row_exchange (U, i, i-1); | |
2462 | } | |
2463 | } | |
2464 | } | |
2465 | } | |
2466 | } | |
2467 | ||
2146e26d | 2468 | /* Determines the overlapping elements due to accesses CHREC_A and |
6b421feb | 2469 | CHREC_B, that are affine functions. This function cannot handle |
2470 | symbolic evolution functions, ie. when initial conditions are | |
2471 | parameters, because it uses lambda matrices of integers. */ | |
2146e26d | 2472 | |
2473 | static void | |
48e1416a | 2474 | analyze_subscript_affine_affine (tree chrec_a, |
2146e26d | 2475 | tree chrec_b, |
48e1416a | 2476 | conflict_function **overlaps_a, |
2477 | conflict_function **overlaps_b, | |
bc3c8ad4 | 2478 | tree *last_conflicts) |
2146e26d | 2479 | { |
bc3c8ad4 | 2480 | unsigned nb_vars_a, nb_vars_b, dim; |
4ee81b10 | 2481 | HOST_WIDE_INT init_a, init_b, gamma, gcd_alpha_beta; |
bc3c8ad4 | 2482 | lambda_matrix A, U, S; |
1e33ad50 | 2483 | struct obstack scratch_obstack; |
bc3c8ad4 | 2484 | |
f84a688a | 2485 | if (eq_evolutions_p (chrec_a, chrec_b)) |
b6d41046 | 2486 | { |
f84a688a | 2487 | /* The accessed index overlaps for each iteration in the |
2488 | loop. */ | |
87da4f2e | 2489 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2490 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
b6d41046 | 2491 | *last_conflicts = chrec_dont_know; |
2492 | return; | |
2493 | } | |
2146e26d | 2494 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2495 | fprintf (dump_file, "(analyze_subscript_affine_affine \n"); | |
48e1416a | 2496 | |
2146e26d | 2497 | /* For determining the initial intersection, we have to solve a |
2498 | Diophantine equation. This is the most time consuming part. | |
48e1416a | 2499 | |
2146e26d | 2500 | For answering to the question: "Is there a dependence?" we have |
2501 | to prove that there exists a solution to the Diophantine | |
2502 | equation, and that the solution is in the iteration domain, | |
5c9dae64 | 2503 | i.e. the solution is positive or zero, and that the solution |
2146e26d | 2504 | happens before the upper bound loop.nb_iterations. Otherwise |
2505 | there is no dependence. This function outputs a description of | |
2506 | the iterations that hold the intersections. */ | |
2507 | ||
bc3c8ad4 | 2508 | nb_vars_a = nb_vars_in_chrec (chrec_a); |
2509 | nb_vars_b = nb_vars_in_chrec (chrec_b); | |
2510 | ||
1e33ad50 | 2511 | gcc_obstack_init (&scratch_obstack); |
2512 | ||
bc3c8ad4 | 2513 | dim = nb_vars_a + nb_vars_b; |
1e33ad50 | 2514 | U = lambda_matrix_new (dim, dim, &scratch_obstack); |
2515 | A = lambda_matrix_new (dim, 1, &scratch_obstack); | |
2516 | S = lambda_matrix_new (dim, 1, &scratch_obstack); | |
bc3c8ad4 | 2517 | |
8ceddf57 | 2518 | init_a = int_cst_value (initialize_matrix_A (A, chrec_a, 0, 1)); |
2519 | init_b = int_cst_value (initialize_matrix_A (A, chrec_b, nb_vars_a, -1)); | |
bc3c8ad4 | 2520 | gamma = init_b - init_a; |
2521 | ||
2522 | /* Don't do all the hard work of solving the Diophantine equation | |
48e1416a | 2523 | when we already know the solution: for example, |
bc3c8ad4 | 2524 | | {3, +, 1}_1 |
2525 | | {3, +, 4}_2 | |
2526 | | gamma = 3 - 3 = 0. | |
48e1416a | 2527 | Then the first overlap occurs during the first iterations: |
bc3c8ad4 | 2528 | | {3, +, 1}_1 ({0, +, 4}_x) = {3, +, 4}_2 ({0, +, 1}_x) |
2529 | */ | |
2530 | if (gamma == 0) | |
2146e26d | 2531 | { |
bc3c8ad4 | 2532 | if (nb_vars_a == 1 && nb_vars_b == 1) |
2146e26d | 2533 | { |
4ee81b10 | 2534 | HOST_WIDE_INT step_a, step_b; |
d500fef3 | 2535 | HOST_WIDE_INT niter, niter_a, niter_b; |
87da4f2e | 2536 | affine_fn ova, ovb; |
bc3c8ad4 | 2537 | |
fee017b3 | 2538 | niter_a = max_stmt_executions_int (get_chrec_loop (chrec_a)); |
2539 | niter_b = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
bc3c8ad4 | 2540 | niter = MIN (niter_a, niter_b); |
58f77a87 | 2541 | step_a = int_cst_value (CHREC_RIGHT (chrec_a)); |
2542 | step_b = int_cst_value (CHREC_RIGHT (chrec_b)); | |
bc3c8ad4 | 2543 | |
48e1416a | 2544 | compute_overlap_steps_for_affine_univar (niter, step_a, step_b, |
2545 | &ova, &ovb, | |
bc3c8ad4 | 2546 | last_conflicts, 1); |
87da4f2e | 2547 | *overlaps_a = conflict_fn (1, ova); |
2548 | *overlaps_b = conflict_fn (1, ovb); | |
2146e26d | 2549 | } |
bc3c8ad4 | 2550 | |
2551 | else if (nb_vars_a == 2 && nb_vars_b == 1) | |
2552 | compute_overlap_steps_for_affine_1_2 | |
2553 | (chrec_a, chrec_b, overlaps_a, overlaps_b, last_conflicts); | |
2554 | ||
2555 | else if (nb_vars_a == 1 && nb_vars_b == 2) | |
2556 | compute_overlap_steps_for_affine_1_2 | |
2557 | (chrec_b, chrec_a, overlaps_b, overlaps_a, last_conflicts); | |
2558 | ||
2559 | else | |
2146e26d | 2560 | { |
6b421feb | 2561 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2562 | fprintf (dump_file, "affine-affine test failed: too many variables.\n"); | |
87da4f2e | 2563 | *overlaps_a = conflict_fn_not_known (); |
2564 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 2565 | *last_conflicts = chrec_dont_know; |
2146e26d | 2566 | } |
6b421feb | 2567 | goto end_analyze_subs_aa; |
bc3c8ad4 | 2568 | } |
2569 | ||
2570 | /* U.A = S */ | |
2571 | lambda_matrix_right_hermite (A, dim, 1, S, U); | |
2572 | ||
2573 | if (S[0][0] < 0) | |
2574 | { | |
2575 | S[0][0] *= -1; | |
2576 | lambda_matrix_row_negate (U, dim, 0); | |
2577 | } | |
2578 | gcd_alpha_beta = S[0][0]; | |
2579 | ||
b44d1046 | 2580 | /* Something went wrong: for example in {1, +, 0}_5 vs. {0, +, 0}_5, |
2581 | but that is a quite strange case. Instead of ICEing, answer | |
2582 | don't know. */ | |
2583 | if (gcd_alpha_beta == 0) | |
2584 | { | |
87da4f2e | 2585 | *overlaps_a = conflict_fn_not_known (); |
2586 | *overlaps_b = conflict_fn_not_known (); | |
b44d1046 | 2587 | *last_conflicts = chrec_dont_know; |
2588 | goto end_analyze_subs_aa; | |
2589 | } | |
2590 | ||
bc3c8ad4 | 2591 | /* The classic "gcd-test". */ |
2592 | if (!int_divides_p (gcd_alpha_beta, gamma)) | |
2593 | { | |
2594 | /* The "gcd-test" has determined that there is no integer | |
2595 | solution, i.e. there is no dependence. */ | |
87da4f2e | 2596 | *overlaps_a = conflict_fn_no_dependence (); |
2597 | *overlaps_b = conflict_fn_no_dependence (); | |
bc3c8ad4 | 2598 | *last_conflicts = integer_zero_node; |
2599 | } | |
2600 | ||
2601 | /* Both access functions are univariate. This includes SIV and MIV cases. */ | |
2602 | else if (nb_vars_a == 1 && nb_vars_b == 1) | |
2603 | { | |
2604 | /* Both functions should have the same evolution sign. */ | |
2605 | if (((A[0][0] > 0 && -A[1][0] > 0) | |
2606 | || (A[0][0] < 0 && -A[1][0] < 0))) | |
2146e26d | 2607 | { |
2608 | /* The solutions are given by: | |
48e1416a | 2609 | | |
bc3c8ad4 | 2610 | | [GAMMA/GCD_ALPHA_BETA t].[u11 u12] = [x0] |
2611 | | [u21 u22] [y0] | |
48e1416a | 2612 | |
2146e26d | 2613 | For a given integer t. Using the following variables, |
48e1416a | 2614 | |
2146e26d | 2615 | | i0 = u11 * gamma / gcd_alpha_beta |
2616 | | j0 = u12 * gamma / gcd_alpha_beta | |
2617 | | i1 = u21 | |
2618 | | j1 = u22 | |
48e1416a | 2619 | |
2146e26d | 2620 | the solutions are: |
48e1416a | 2621 | |
2622 | | x0 = i0 + i1 * t, | |
bc3c8ad4 | 2623 | | y0 = j0 + j1 * t. */ |
e781c550 | 2624 | HOST_WIDE_INT i0, j0, i1, j1; |
bc3c8ad4 | 2625 | |
2626 | i0 = U[0][0] * gamma / gcd_alpha_beta; | |
2627 | j0 = U[0][1] * gamma / gcd_alpha_beta; | |
2628 | i1 = U[1][0]; | |
2629 | j1 = U[1][1]; | |
2630 | ||
2631 | if ((i1 == 0 && i0 < 0) | |
2632 | || (j1 == 0 && j0 < 0)) | |
2146e26d | 2633 | { |
48e1416a | 2634 | /* There is no solution. |
2635 | FIXME: The case "i0 > nb_iterations, j0 > nb_iterations" | |
2636 | falls in here, but for the moment we don't look at the | |
2146e26d | 2637 | upper bound of the iteration domain. */ |
87da4f2e | 2638 | *overlaps_a = conflict_fn_no_dependence (); |
2639 | *overlaps_b = conflict_fn_no_dependence (); | |
bc3c8ad4 | 2640 | *last_conflicts = integer_zero_node; |
e781c550 | 2641 | goto end_analyze_subs_aa; |
bc3c8ad4 | 2642 | } |
2643 | ||
e781c550 | 2644 | if (i1 > 0 && j1 > 0) |
2146e26d | 2645 | { |
fee017b3 | 2646 | HOST_WIDE_INT niter_a |
2647 | = max_stmt_executions_int (get_chrec_loop (chrec_a)); | |
2648 | HOST_WIDE_INT niter_b | |
2649 | = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
e781c550 | 2650 | HOST_WIDE_INT niter = MIN (niter_a, niter_b); |
2651 | ||
2652 | /* (X0, Y0) is a solution of the Diophantine equation: | |
2653 | "chrec_a (X0) = chrec_b (Y0)". */ | |
2654 | HOST_WIDE_INT tau1 = MAX (CEIL (-i0, i1), | |
2655 | CEIL (-j0, j1)); | |
2656 | HOST_WIDE_INT x0 = i1 * tau1 + i0; | |
2657 | HOST_WIDE_INT y0 = j1 * tau1 + j0; | |
2658 | ||
2659 | /* (X1, Y1) is the smallest positive solution of the eq | |
2660 | "chrec_a (X1) = chrec_b (Y1)", i.e. this is where the | |
2661 | first conflict occurs. */ | |
2662 | HOST_WIDE_INT min_multiple = MIN (x0 / i1, y0 / j1); | |
2663 | HOST_WIDE_INT x1 = x0 - i1 * min_multiple; | |
2664 | HOST_WIDE_INT y1 = y0 - j1 * min_multiple; | |
2665 | ||
2666 | if (niter > 0) | |
2146e26d | 2667 | { |
e781c550 | 2668 | HOST_WIDE_INT tau2 = MIN (FLOOR_DIV (niter - i0, i1), |
2669 | FLOOR_DIV (niter - j0, j1)); | |
2670 | HOST_WIDE_INT last_conflict = tau2 - (x1 - i0)/i1; | |
bc3c8ad4 | 2671 | |
e781c550 | 2672 | /* If the overlap occurs outside of the bounds of the |
2673 | loop, there is no dependence. */ | |
63ca8934 | 2674 | if (x1 >= niter || y1 >= niter) |
2146e26d | 2675 | { |
e781c550 | 2676 | *overlaps_a = conflict_fn_no_dependence (); |
2677 | *overlaps_b = conflict_fn_no_dependence (); | |
2678 | *last_conflicts = integer_zero_node; | |
2679 | goto end_analyze_subs_aa; | |
2146e26d | 2680 | } |
2681 | else | |
e781c550 | 2682 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); |
2146e26d | 2683 | } |
2146e26d | 2684 | else |
e781c550 | 2685 | *last_conflicts = chrec_dont_know; |
2686 | ||
2687 | *overlaps_a | |
2688 | = conflict_fn (1, | |
2689 | affine_fn_univar (build_int_cst (NULL_TREE, x1), | |
2690 | 1, | |
2691 | build_int_cst (NULL_TREE, i1))); | |
2692 | *overlaps_b | |
2693 | = conflict_fn (1, | |
2694 | affine_fn_univar (build_int_cst (NULL_TREE, y1), | |
2695 | 1, | |
2696 | build_int_cst (NULL_TREE, j1))); | |
2697 | } | |
2698 | else | |
2699 | { | |
2700 | /* FIXME: For the moment, the upper bound of the | |
2701 | iteration domain for i and j is not checked. */ | |
2702 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2703 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
2704 | *overlaps_a = conflict_fn_not_known (); | |
2705 | *overlaps_b = conflict_fn_not_known (); | |
2706 | *last_conflicts = chrec_dont_know; | |
2146e26d | 2707 | } |
2708 | } | |
bc3c8ad4 | 2709 | else |
2710 | { | |
6b421feb | 2711 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2712 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
87da4f2e | 2713 | *overlaps_a = conflict_fn_not_known (); |
2714 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 2715 | *last_conflicts = chrec_dont_know; |
2716 | } | |
2146e26d | 2717 | } |
2146e26d | 2718 | else |
2719 | { | |
6b421feb | 2720 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2721 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
87da4f2e | 2722 | *overlaps_a = conflict_fn_not_known (); |
2723 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 2724 | *last_conflicts = chrec_dont_know; |
2146e26d | 2725 | } |
bc3c8ad4 | 2726 | |
48e1416a | 2727 | end_analyze_subs_aa: |
1e33ad50 | 2728 | obstack_free (&scratch_obstack, NULL); |
2146e26d | 2729 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2730 | { | |
2731 | fprintf (dump_file, " (overlaps_a = "); | |
87da4f2e | 2732 | dump_conflict_function (dump_file, *overlaps_a); |
2146e26d | 2733 | fprintf (dump_file, ")\n (overlaps_b = "); |
87da4f2e | 2734 | dump_conflict_function (dump_file, *overlaps_b); |
984cebc1 | 2735 | fprintf (dump_file, "))\n"); |
2146e26d | 2736 | } |
6b421feb | 2737 | } |
2738 | ||
2739 | /* Returns true when analyze_subscript_affine_affine can be used for | |
2740 | determining the dependence relation between chrec_a and chrec_b, | |
2741 | that contain symbols. This function modifies chrec_a and chrec_b | |
2742 | such that the analysis result is the same, and such that they don't | |
48e1416a | 2743 | contain symbols, and then can safely be passed to the analyzer. |
6b421feb | 2744 | |
2745 | Example: The analysis of the following tuples of evolutions produce | |
2746 | the same results: {x+1, +, 1}_1 vs. {x+3, +, 1}_1, and {-2, +, 1}_1 | |
2747 | vs. {0, +, 1}_1 | |
48e1416a | 2748 | |
6b421feb | 2749 | {x+1, +, 1}_1 ({2, +, 1}_1) = {x+3, +, 1}_1 ({0, +, 1}_1) |
2750 | {-2, +, 1}_1 ({2, +, 1}_1) = {0, +, 1}_1 ({0, +, 1}_1) | |
2751 | */ | |
2752 | ||
2753 | static bool | |
2754 | can_use_analyze_subscript_affine_affine (tree *chrec_a, tree *chrec_b) | |
2755 | { | |
b92381b6 | 2756 | tree diff, type, left_a, left_b, right_b; |
6b421feb | 2757 | |
2758 | if (chrec_contains_symbols (CHREC_RIGHT (*chrec_a)) | |
2759 | || chrec_contains_symbols (CHREC_RIGHT (*chrec_b))) | |
2760 | /* FIXME: For the moment not handled. Might be refined later. */ | |
2761 | return false; | |
2762 | ||
b92381b6 | 2763 | type = chrec_type (*chrec_a); |
2764 | left_a = CHREC_LEFT (*chrec_a); | |
75a70cf9 | 2765 | left_b = chrec_convert (type, CHREC_LEFT (*chrec_b), NULL); |
b92381b6 | 2766 | diff = chrec_fold_minus (type, left_a, left_b); |
2767 | ||
6b421feb | 2768 | if (!evolution_function_is_constant_p (diff)) |
2769 | return false; | |
2770 | ||
2146e26d | 2771 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6b421feb | 2772 | fprintf (dump_file, "can_use_subscript_aff_aff_for_symbolic \n"); |
2773 | ||
48e1416a | 2774 | *chrec_a = build_polynomial_chrec (CHREC_VARIABLE (*chrec_a), |
6b421feb | 2775 | diff, CHREC_RIGHT (*chrec_a)); |
75a70cf9 | 2776 | right_b = chrec_convert (type, CHREC_RIGHT (*chrec_b), NULL); |
6b421feb | 2777 | *chrec_b = build_polynomial_chrec (CHREC_VARIABLE (*chrec_b), |
7c010d6a | 2778 | build_int_cst (type, 0), |
b92381b6 | 2779 | right_b); |
6b421feb | 2780 | return true; |
2146e26d | 2781 | } |
2782 | ||
2783 | /* Analyze a SIV (Single Index Variable) subscript. *OVERLAPS_A and | |
2784 | *OVERLAPS_B are initialized to the functions that describe the | |
2785 | relation between the elements accessed twice by CHREC_A and | |
2786 | CHREC_B. For k >= 0, the following property is verified: | |
2787 | ||
2788 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2789 | ||
2790 | static void | |
48e1416a | 2791 | analyze_siv_subscript (tree chrec_a, |
2146e26d | 2792 | tree chrec_b, |
48e1416a | 2793 | conflict_function **overlaps_a, |
2794 | conflict_function **overlaps_b, | |
8ceddf57 | 2795 | tree *last_conflicts, |
2796 | int loop_nest_num) | |
2146e26d | 2797 | { |
6b421feb | 2798 | dependence_stats.num_siv++; |
48e1416a | 2799 | |
2146e26d | 2800 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2801 | fprintf (dump_file, "(analyze_siv_subscript \n"); | |
48e1416a | 2802 | |
2146e26d | 2803 | if (evolution_function_is_constant_p (chrec_a) |
8ceddf57 | 2804 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) |
48e1416a | 2805 | analyze_siv_subscript_cst_affine (chrec_a, chrec_b, |
bc3c8ad4 | 2806 | overlaps_a, overlaps_b, last_conflicts); |
48e1416a | 2807 | |
8ceddf57 | 2808 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
2146e26d | 2809 | && evolution_function_is_constant_p (chrec_b)) |
48e1416a | 2810 | analyze_siv_subscript_cst_affine (chrec_b, chrec_a, |
bc3c8ad4 | 2811 | overlaps_b, overlaps_a, last_conflicts); |
48e1416a | 2812 | |
8ceddf57 | 2813 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
2814 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) | |
6b421feb | 2815 | { |
2816 | if (!chrec_contains_symbols (chrec_a) | |
2817 | && !chrec_contains_symbols (chrec_b)) | |
2818 | { | |
48e1416a | 2819 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2820 | overlaps_a, overlaps_b, | |
6b421feb | 2821 | last_conflicts); |
2822 | ||
87da4f2e | 2823 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2824 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
6b421feb | 2825 | dependence_stats.num_siv_unimplemented++; |
87da4f2e | 2826 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2827 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
6b421feb | 2828 | dependence_stats.num_siv_independent++; |
2829 | else | |
2830 | dependence_stats.num_siv_dependent++; | |
2831 | } | |
48e1416a | 2832 | else if (can_use_analyze_subscript_affine_affine (&chrec_a, |
6b421feb | 2833 | &chrec_b)) |
2834 | { | |
48e1416a | 2835 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2836 | overlaps_a, overlaps_b, | |
6b421feb | 2837 | last_conflicts); |
6b421feb | 2838 | |
87da4f2e | 2839 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2840 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
6b421feb | 2841 | dependence_stats.num_siv_unimplemented++; |
87da4f2e | 2842 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2843 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
6b421feb | 2844 | dependence_stats.num_siv_independent++; |
2845 | else | |
2846 | dependence_stats.num_siv_dependent++; | |
2847 | } | |
2848 | else | |
2849 | goto siv_subscript_dontknow; | |
2850 | } | |
2851 | ||
2146e26d | 2852 | else |
2853 | { | |
6b421feb | 2854 | siv_subscript_dontknow:; |
2855 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
984cebc1 | 2856 | fprintf (dump_file, " siv test failed: unimplemented"); |
87da4f2e | 2857 | *overlaps_a = conflict_fn_not_known (); |
2858 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 2859 | *last_conflicts = chrec_dont_know; |
6b421feb | 2860 | dependence_stats.num_siv_unimplemented++; |
2146e26d | 2861 | } |
48e1416a | 2862 | |
2146e26d | 2863 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2864 | fprintf (dump_file, ")\n"); | |
2865 | } | |
2866 | ||
cabedb72 | 2867 | /* Returns false if we can prove that the greatest common divisor of the steps |
2868 | of CHREC does not divide CST, false otherwise. */ | |
2146e26d | 2869 | |
2870 | static bool | |
7ecb5bb2 | 2871 | gcd_of_steps_may_divide_p (const_tree chrec, const_tree cst) |
2146e26d | 2872 | { |
cabedb72 | 2873 | HOST_WIDE_INT cd = 0, val; |
2874 | tree step; | |
6b421feb | 2875 | |
e913b5cd | 2876 | if (!tree_fits_shwi_p (cst)) |
cabedb72 | 2877 | return true; |
e913b5cd | 2878 | val = tree_to_shwi (cst); |
cabedb72 | 2879 | |
2880 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC) | |
2881 | { | |
2882 | step = CHREC_RIGHT (chrec); | |
e913b5cd | 2883 | if (!tree_fits_shwi_p (step)) |
cabedb72 | 2884 | return true; |
e913b5cd | 2885 | cd = gcd (cd, tree_to_shwi (step)); |
cabedb72 | 2886 | chrec = CHREC_LEFT (chrec); |
2146e26d | 2887 | } |
cabedb72 | 2888 | |
2889 | return val % cd == 0; | |
2146e26d | 2890 | } |
2891 | ||
8c7b1d8e | 2892 | /* Analyze a MIV (Multiple Index Variable) subscript with respect to |
2893 | LOOP_NEST. *OVERLAPS_A and *OVERLAPS_B are initialized to the | |
2894 | functions that describe the relation between the elements accessed | |
2895 | twice by CHREC_A and CHREC_B. For k >= 0, the following property | |
2896 | is verified: | |
2146e26d | 2897 | |
2898 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2899 | ||
2900 | static void | |
48e1416a | 2901 | analyze_miv_subscript (tree chrec_a, |
2902 | tree chrec_b, | |
2903 | conflict_function **overlaps_a, | |
2904 | conflict_function **overlaps_b, | |
8c7b1d8e | 2905 | tree *last_conflicts, |
2906 | struct loop *loop_nest) | |
2146e26d | 2907 | { |
9a3dad1c | 2908 | tree type, difference; |
2909 | ||
6b421feb | 2910 | dependence_stats.num_miv++; |
2146e26d | 2911 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2912 | fprintf (dump_file, "(analyze_miv_subscript \n"); | |
f84a688a | 2913 | |
9a3dad1c | 2914 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
75a70cf9 | 2915 | chrec_a = chrec_convert (type, chrec_a, NULL); |
2916 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
9a3dad1c | 2917 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
48e1416a | 2918 | |
f84a688a | 2919 | if (eq_evolutions_p (chrec_a, chrec_b)) |
2146e26d | 2920 | { |
2921 | /* Access functions are the same: all the elements are accessed | |
2922 | in the same order. */ | |
87da4f2e | 2923 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2924 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
8fe79ba5 | 2925 | *last_conflicts = max_stmt_executions_tree (get_chrec_loop (chrec_a)); |
6b421feb | 2926 | dependence_stats.num_miv_dependent++; |
2146e26d | 2927 | } |
48e1416a | 2928 | |
2146e26d | 2929 | else if (evolution_function_is_constant_p (difference) |
2930 | /* For the moment, the following is verified: | |
8c7b1d8e | 2931 | evolution_function_is_affine_multivariate_p (chrec_a, |
2932 | loop_nest->num) */ | |
cabedb72 | 2933 | && !gcd_of_steps_may_divide_p (chrec_a, difference)) |
2146e26d | 2934 | { |
2935 | /* testsuite/.../ssa-chrec-33.c | |
48e1416a | 2936 | {{21, +, 2}_1, +, -2}_2 vs. {{20, +, 2}_1, +, -2}_2 |
2937 | ||
cabedb72 | 2938 | The difference is 1, and all the evolution steps are multiples |
2939 | of 2, consequently there are no overlapping elements. */ | |
87da4f2e | 2940 | *overlaps_a = conflict_fn_no_dependence (); |
2941 | *overlaps_b = conflict_fn_no_dependence (); | |
bc3c8ad4 | 2942 | *last_conflicts = integer_zero_node; |
6b421feb | 2943 | dependence_stats.num_miv_independent++; |
2146e26d | 2944 | } |
48e1416a | 2945 | |
8c7b1d8e | 2946 | else if (evolution_function_is_affine_multivariate_p (chrec_a, loop_nest->num) |
6b421feb | 2947 | && !chrec_contains_symbols (chrec_a) |
8c7b1d8e | 2948 | && evolution_function_is_affine_multivariate_p (chrec_b, loop_nest->num) |
6b421feb | 2949 | && !chrec_contains_symbols (chrec_b)) |
2146e26d | 2950 | { |
2951 | /* testsuite/.../ssa-chrec-35.c | |
2952 | {0, +, 1}_2 vs. {0, +, 1}_3 | |
2953 | the overlapping elements are respectively located at iterations: | |
48e1416a | 2954 | {0, +, 1}_x and {0, +, 1}_x, |
2955 | in other words, we have the equality: | |
bc3c8ad4 | 2956 | {0, +, 1}_2 ({0, +, 1}_x) = {0, +, 1}_3 ({0, +, 1}_x) |
48e1416a | 2957 | |
2958 | Other examples: | |
2959 | {{0, +, 1}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) = | |
bc3c8ad4 | 2960 | {0, +, 1}_1 ({{0, +, 1}_x, +, 2}_y) |
2961 | ||
48e1416a | 2962 | {{0, +, 2}_1, +, 3}_2 ({0, +, 1}_y, {0, +, 1}_x) = |
bc3c8ad4 | 2963 | {{0, +, 3}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) |
2146e26d | 2964 | */ |
48e1416a | 2965 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
bc3c8ad4 | 2966 | overlaps_a, overlaps_b, last_conflicts); |
6b421feb | 2967 | |
87da4f2e | 2968 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2969 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
6b421feb | 2970 | dependence_stats.num_miv_unimplemented++; |
87da4f2e | 2971 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2972 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
6b421feb | 2973 | dependence_stats.num_miv_independent++; |
2974 | else | |
2975 | dependence_stats.num_miv_dependent++; | |
2146e26d | 2976 | } |
48e1416a | 2977 | |
2146e26d | 2978 | else |
2979 | { | |
2980 | /* When the analysis is too difficult, answer "don't know". */ | |
6b421feb | 2981 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2982 | fprintf (dump_file, "analyze_miv_subscript test failed: unimplemented.\n"); | |
2983 | ||
87da4f2e | 2984 | *overlaps_a = conflict_fn_not_known (); |
2985 | *overlaps_b = conflict_fn_not_known (); | |
bc3c8ad4 | 2986 | *last_conflicts = chrec_dont_know; |
6b421feb | 2987 | dependence_stats.num_miv_unimplemented++; |
2146e26d | 2988 | } |
48e1416a | 2989 | |
2146e26d | 2990 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2991 | fprintf (dump_file, ")\n"); | |
2992 | } | |
2993 | ||
8c7b1d8e | 2994 | /* Determines the iterations for which CHREC_A is equal to CHREC_B in |
2995 | with respect to LOOP_NEST. OVERLAP_ITERATIONS_A and | |
2996 | OVERLAP_ITERATIONS_B are initialized with two functions that | |
2997 | describe the iterations that contain conflicting elements. | |
48e1416a | 2998 | |
2146e26d | 2999 | Remark: For an integer k >= 0, the following equality is true: |
48e1416a | 3000 | |
2146e26d | 3001 | CHREC_A (OVERLAP_ITERATIONS_A (k)) == CHREC_B (OVERLAP_ITERATIONS_B (k)). |
3002 | */ | |
3003 | ||
48e1416a | 3004 | static void |
3005 | analyze_overlapping_iterations (tree chrec_a, | |
3006 | tree chrec_b, | |
3007 | conflict_function **overlap_iterations_a, | |
3008 | conflict_function **overlap_iterations_b, | |
8c7b1d8e | 3009 | tree *last_conflicts, struct loop *loop_nest) |
2146e26d | 3010 | { |
8c7b1d8e | 3011 | unsigned int lnn = loop_nest->num; |
3012 | ||
6b421feb | 3013 | dependence_stats.num_subscript_tests++; |
48e1416a | 3014 | |
2146e26d | 3015 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3016 | { | |
3017 | fprintf (dump_file, "(analyze_overlapping_iterations \n"); | |
3018 | fprintf (dump_file, " (chrec_a = "); | |
3019 | print_generic_expr (dump_file, chrec_a, 0); | |
6b421feb | 3020 | fprintf (dump_file, ")\n (chrec_b = "); |
2146e26d | 3021 | print_generic_expr (dump_file, chrec_b, 0); |
3022 | fprintf (dump_file, ")\n"); | |
3023 | } | |
6b421feb | 3024 | |
2146e26d | 3025 | if (chrec_a == NULL_TREE |
3026 | || chrec_b == NULL_TREE | |
3027 | || chrec_contains_undetermined (chrec_a) | |
6b421feb | 3028 | || chrec_contains_undetermined (chrec_b)) |
2146e26d | 3029 | { |
6b421feb | 3030 | dependence_stats.num_subscript_undetermined++; |
48e1416a | 3031 | |
87da4f2e | 3032 | *overlap_iterations_a = conflict_fn_not_known (); |
3033 | *overlap_iterations_b = conflict_fn_not_known (); | |
2146e26d | 3034 | } |
6b421feb | 3035 | |
48e1416a | 3036 | /* If they are the same chrec, and are affine, they overlap |
6b421feb | 3037 | on every iteration. */ |
3038 | else if (eq_evolutions_p (chrec_a, chrec_b) | |
328218c2 | 3039 | && (evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
3040 | || operand_equal_p (chrec_a, chrec_b, 0))) | |
6b421feb | 3041 | { |
3042 | dependence_stats.num_same_subscript_function++; | |
87da4f2e | 3043 | *overlap_iterations_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
3044 | *overlap_iterations_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
6b421feb | 3045 | *last_conflicts = chrec_dont_know; |
3046 | } | |
3047 | ||
3048 | /* If they aren't the same, and aren't affine, we can't do anything | |
328218c2 | 3049 | yet. */ |
48e1416a | 3050 | else if ((chrec_contains_symbols (chrec_a) |
6b421feb | 3051 | || chrec_contains_symbols (chrec_b)) |
8c7b1d8e | 3052 | && (!evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
3053 | || !evolution_function_is_affine_multivariate_p (chrec_b, lnn))) | |
6b421feb | 3054 | { |
3055 | dependence_stats.num_subscript_undetermined++; | |
87da4f2e | 3056 | *overlap_iterations_a = conflict_fn_not_known (); |
3057 | *overlap_iterations_b = conflict_fn_not_known (); | |
6b421feb | 3058 | } |
3059 | ||
2146e26d | 3060 | else if (ziv_subscript_p (chrec_a, chrec_b)) |
48e1416a | 3061 | analyze_ziv_subscript (chrec_a, chrec_b, |
bc3c8ad4 | 3062 | overlap_iterations_a, overlap_iterations_b, |
3063 | last_conflicts); | |
48e1416a | 3064 | |
2146e26d | 3065 | else if (siv_subscript_p (chrec_a, chrec_b)) |
48e1416a | 3066 | analyze_siv_subscript (chrec_a, chrec_b, |
3067 | overlap_iterations_a, overlap_iterations_b, | |
8ceddf57 | 3068 | last_conflicts, lnn); |
48e1416a | 3069 | |
2146e26d | 3070 | else |
48e1416a | 3071 | analyze_miv_subscript (chrec_a, chrec_b, |
bc3c8ad4 | 3072 | overlap_iterations_a, overlap_iterations_b, |
8c7b1d8e | 3073 | last_conflicts, loop_nest); |
48e1416a | 3074 | |
2146e26d | 3075 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3076 | { | |
3077 | fprintf (dump_file, " (overlap_iterations_a = "); | |
87da4f2e | 3078 | dump_conflict_function (dump_file, *overlap_iterations_a); |
2146e26d | 3079 | fprintf (dump_file, ")\n (overlap_iterations_b = "); |
87da4f2e | 3080 | dump_conflict_function (dump_file, *overlap_iterations_b); |
984cebc1 | 3081 | fprintf (dump_file, "))\n"); |
2146e26d | 3082 | } |
3083 | } | |
3084 | ||
b44d1046 | 3085 | /* Helper function for uniquely inserting distance vectors. */ |
2146e26d | 3086 | |
b44d1046 | 3087 | static void |
3088 | save_dist_v (struct data_dependence_relation *ddr, lambda_vector dist_v) | |
3089 | { | |
3090 | unsigned i; | |
3091 | lambda_vector v; | |
2146e26d | 3092 | |
f1f41a6c | 3093 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, v) |
b44d1046 | 3094 | if (lambda_vector_equal (v, dist_v, DDR_NB_LOOPS (ddr))) |
3095 | return; | |
2146e26d | 3096 | |
f1f41a6c | 3097 | DDR_DIST_VECTS (ddr).safe_push (dist_v); |
b44d1046 | 3098 | } |
2146e26d | 3099 | |
b44d1046 | 3100 | /* Helper function for uniquely inserting direction vectors. */ |
3101 | ||
3102 | static void | |
3103 | save_dir_v (struct data_dependence_relation *ddr, lambda_vector dir_v) | |
2146e26d | 3104 | { |
3105 | unsigned i; | |
b44d1046 | 3106 | lambda_vector v; |
6b421feb | 3107 | |
f1f41a6c | 3108 | FOR_EACH_VEC_ELT (DDR_DIR_VECTS (ddr), i, v) |
b44d1046 | 3109 | if (lambda_vector_equal (v, dir_v, DDR_NB_LOOPS (ddr))) |
3110 | return; | |
3111 | ||
f1f41a6c | 3112 | DDR_DIR_VECTS (ddr).safe_push (dir_v); |
b44d1046 | 3113 | } |
3114 | ||
3115 | /* Add a distance of 1 on all the loops outer than INDEX. If we | |
3116 | haven't yet determined a distance for this outer loop, push a new | |
3117 | distance vector composed of the previous distance, and a distance | |
3118 | of 1 for this outer loop. Example: | |
3119 | ||
3120 | | loop_1 | |
3121 | | loop_2 | |
3122 | | A[10] | |
3123 | | endloop_2 | |
3124 | | endloop_1 | |
3125 | ||
3126 | Saved vectors are of the form (dist_in_1, dist_in_2). First, we | |
3127 | save (0, 1), then we have to save (1, 0). */ | |
3128 | ||
3129 | static void | |
3130 | add_outer_distances (struct data_dependence_relation *ddr, | |
3131 | lambda_vector dist_v, int index) | |
3132 | { | |
3133 | /* For each outer loop where init_v is not set, the accesses are | |
3134 | in dependence of distance 1 in the loop. */ | |
3135 | while (--index >= 0) | |
3136 | { | |
3137 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3138 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
3139 | save_v[index] = 1; | |
3140 | save_dist_v (ddr, save_v); | |
3141 | } | |
3142 | } | |
3143 | ||
3144 | /* Return false when fail to represent the data dependence as a | |
3145 | distance vector. INIT_B is set to true when a component has been | |
3146 | added to the distance vector DIST_V. INDEX_CARRY is then set to | |
3147 | the index in DIST_V that carries the dependence. */ | |
3148 | ||
3149 | static bool | |
3150 | build_classic_dist_vector_1 (struct data_dependence_relation *ddr, | |
3151 | struct data_reference *ddr_a, | |
3152 | struct data_reference *ddr_b, | |
3153 | lambda_vector dist_v, bool *init_b, | |
3154 | int *index_carry) | |
3155 | { | |
3156 | unsigned i; | |
3157 | lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
6b421feb | 3158 | |
6b6f234c | 3159 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
2146e26d | 3160 | { |
bc3c8ad4 | 3161 | tree access_fn_a, access_fn_b; |
6b6f234c | 3162 | struct subscript *subscript = DDR_SUBSCRIPT (ddr, i); |
2146e26d | 3163 | |
3164 | if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
bc3c8ad4 | 3165 | { |
3166 | non_affine_dependence_relation (ddr); | |
b44d1046 | 3167 | return false; |
bc3c8ad4 | 3168 | } |
3169 | ||
b44d1046 | 3170 | access_fn_a = DR_ACCESS_FN (ddr_a, i); |
3171 | access_fn_b = DR_ACCESS_FN (ddr_b, i); | |
2146e26d | 3172 | |
48e1416a | 3173 | if (TREE_CODE (access_fn_a) == POLYNOMIAL_CHREC |
bc3c8ad4 | 3174 | && TREE_CODE (access_fn_b) == POLYNOMIAL_CHREC) |
2146e26d | 3175 | { |
b44d1046 | 3176 | int dist, index; |
ba3fc4d0 | 3177 | int var_a = CHREC_VARIABLE (access_fn_a); |
3178 | int var_b = CHREC_VARIABLE (access_fn_b); | |
b44d1046 | 3179 | |
ba3fc4d0 | 3180 | if (var_a != var_b |
3181 | || chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
bc3c8ad4 | 3182 | { |
3183 | non_affine_dependence_relation (ddr); | |
b44d1046 | 3184 | return false; |
bc3c8ad4 | 3185 | } |
48e1416a | 3186 | |
58f77a87 | 3187 | dist = int_cst_value (SUB_DISTANCE (subscript)); |
ba3fc4d0 | 3188 | index = index_in_loop_nest (var_a, DDR_LOOP_NEST (ddr)); |
3189 | *index_carry = MIN (index, *index_carry); | |
2146e26d | 3190 | |
b44d1046 | 3191 | /* This is the subscript coupling test. If we have already |
3192 | recorded a distance for this loop (a distance coming from | |
3193 | another subscript), it should be the same. For example, | |
3194 | in the following code, there is no dependence: | |
3195 | ||
2146e26d | 3196 | | loop i = 0, N, 1 |
3197 | | T[i+1][i] = ... | |
3198 | | ... = T[i][i] | |
3199 | | endloop | |
b44d1046 | 3200 | */ |
3201 | if (init_v[index] != 0 && dist_v[index] != dist) | |
2146e26d | 3202 | { |
6b6f234c | 3203 | finalize_ddr_dependent (ddr, chrec_known); |
b44d1046 | 3204 | return false; |
2146e26d | 3205 | } |
3206 | ||
b44d1046 | 3207 | dist_v[index] = dist; |
3208 | init_v[index] = 1; | |
3209 | *init_b = true; | |
3210 | } | |
9c77efff | 3211 | else if (!operand_equal_p (access_fn_a, access_fn_b, 0)) |
b44d1046 | 3212 | { |
3213 | /* This can be for example an affine vs. constant dependence | |
3214 | (T[i] vs. T[3]) that is not an affine dependence and is | |
3215 | not representable as a distance vector. */ | |
3216 | non_affine_dependence_relation (ddr); | |
3217 | return false; | |
2146e26d | 3218 | } |
3219 | } | |
1532ec98 | 3220 | |
b44d1046 | 3221 | return true; |
3222 | } | |
1532ec98 | 3223 | |
2a21a5df | 3224 | /* Return true when the DDR contains only constant access functions. */ |
3225 | ||
3226 | static bool | |
7ecb5bb2 | 3227 | constant_access_functions (const struct data_dependence_relation *ddr) |
2a21a5df | 3228 | { |
3229 | unsigned i; | |
3230 | ||
3231 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3232 | if (!evolution_function_is_constant_p (DR_ACCESS_FN (DDR_A (ddr), i)) | |
3233 | || !evolution_function_is_constant_p (DR_ACCESS_FN (DDR_B (ddr), i))) | |
3234 | return false; | |
3235 | ||
3236 | return true; | |
3237 | } | |
3238 | ||
b44d1046 | 3239 | /* Helper function for the case where DDR_A and DDR_B are the same |
bfe20447 | 3240 | multivariate access function with a constant step. For an example |
3241 | see pr34635-1.c. */ | |
bc3c8ad4 | 3242 | |
b44d1046 | 3243 | static void |
3244 | add_multivariate_self_dist (struct data_dependence_relation *ddr, tree c_2) | |
3245 | { | |
3246 | int x_1, x_2; | |
3247 | tree c_1 = CHREC_LEFT (c_2); | |
3248 | tree c_0 = CHREC_LEFT (c_1); | |
3249 | lambda_vector dist_v; | |
8fb896c4 | 3250 | int v1, v2, cd; |
bc3c8ad4 | 3251 | |
bb11a0e8 | 3252 | /* Polynomials with more than 2 variables are not handled yet. When |
3253 | the evolution steps are parameters, it is not possible to | |
3254 | represent the dependence using classical distance vectors. */ | |
3255 | if (TREE_CODE (c_0) != INTEGER_CST | |
3256 | || TREE_CODE (CHREC_RIGHT (c_1)) != INTEGER_CST | |
3257 | || TREE_CODE (CHREC_RIGHT (c_2)) != INTEGER_CST) | |
3258 | { | |
3259 | DDR_AFFINE_P (ddr) = false; | |
b44d1046 | 3260 | return; |
3261 | } | |
1532ec98 | 3262 | |
b44d1046 | 3263 | x_2 = index_in_loop_nest (CHREC_VARIABLE (c_2), DDR_LOOP_NEST (ddr)); |
3264 | x_1 = index_in_loop_nest (CHREC_VARIABLE (c_1), DDR_LOOP_NEST (ddr)); | |
1532ec98 | 3265 | |
b44d1046 | 3266 | /* For "{{0, +, 2}_1, +, 3}_2" the distance vector is (3, -2). */ |
3267 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
58f77a87 | 3268 | v1 = int_cst_value (CHREC_RIGHT (c_1)); |
3269 | v2 = int_cst_value (CHREC_RIGHT (c_2)); | |
8fb896c4 | 3270 | cd = gcd (v1, v2); |
3271 | v1 /= cd; | |
3272 | v2 /= cd; | |
3273 | ||
3274 | if (v2 < 0) | |
3275 | { | |
3276 | v2 = -v2; | |
3277 | v1 = -v1; | |
3278 | } | |
3279 | ||
3280 | dist_v[x_1] = v2; | |
3281 | dist_v[x_2] = -v1; | |
b44d1046 | 3282 | save_dist_v (ddr, dist_v); |
1532ec98 | 3283 | |
b44d1046 | 3284 | add_outer_distances (ddr, dist_v, x_1); |
3285 | } | |
1532ec98 | 3286 | |
b44d1046 | 3287 | /* Helper function for the case where DDR_A and DDR_B are the same |
3288 | access functions. */ | |
ffe944fa | 3289 | |
b44d1046 | 3290 | static void |
3291 | add_other_self_distances (struct data_dependence_relation *ddr) | |
3292 | { | |
3293 | lambda_vector dist_v; | |
3294 | unsigned i; | |
3295 | int index_carry = DDR_NB_LOOPS (ddr); | |
1532ec98 | 3296 | |
b44d1046 | 3297 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
ffe944fa | 3298 | { |
b44d1046 | 3299 | tree access_fun = DR_ACCESS_FN (DDR_A (ddr), i); |
1532ec98 | 3300 | |
b44d1046 | 3301 | if (TREE_CODE (access_fun) == POLYNOMIAL_CHREC) |
1532ec98 | 3302 | { |
b44d1046 | 3303 | if (!evolution_function_is_univariate_p (access_fun)) |
3304 | { | |
3305 | if (DDR_NUM_SUBSCRIPTS (ddr) != 1) | |
3306 | { | |
3307 | DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; | |
3308 | return; | |
3309 | } | |
3310 | ||
bfe20447 | 3311 | access_fun = DR_ACCESS_FN (DDR_A (ddr), 0); |
3312 | ||
3313 | if (TREE_CODE (CHREC_LEFT (access_fun)) == POLYNOMIAL_CHREC) | |
3314 | add_multivariate_self_dist (ddr, access_fun); | |
3315 | else | |
3316 | /* The evolution step is not constant: it varies in | |
3317 | the outer loop, so this cannot be represented by a | |
3318 | distance vector. For example in pr34635.c the | |
3319 | evolution is {0, +, {0, +, 4}_1}_2. */ | |
3320 | DDR_AFFINE_P (ddr) = false; | |
3321 | ||
b44d1046 | 3322 | return; |
3323 | } | |
3324 | ||
3325 | index_carry = MIN (index_carry, | |
3326 | index_in_loop_nest (CHREC_VARIABLE (access_fun), | |
3327 | DDR_LOOP_NEST (ddr))); | |
1532ec98 | 3328 | } |
ffe944fa | 3329 | } |
3330 | ||
b44d1046 | 3331 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3332 | add_outer_distances (ddr, dist_v, index_carry); | |
2146e26d | 3333 | } |
3334 | ||
2a21a5df | 3335 | static void |
3336 | insert_innermost_unit_dist_vector (struct data_dependence_relation *ddr) | |
3337 | { | |
3338 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3339 | ||
3340 | dist_v[DDR_INNER_LOOP (ddr)] = 1; | |
3341 | save_dist_v (ddr, dist_v); | |
3342 | } | |
3343 | ||
3344 | /* Adds a unit distance vector to DDR when there is a 0 overlap. This | |
3345 | is the case for example when access functions are the same and | |
3346 | equal to a constant, as in: | |
3347 | ||
3348 | | loop_1 | |
3349 | | A[3] = ... | |
3350 | | ... = A[3] | |
3351 | | endloop_1 | |
3352 | ||
3353 | in which case the distance vectors are (0) and (1). */ | |
3354 | ||
3355 | static void | |
3356 | add_distance_for_zero_overlaps (struct data_dependence_relation *ddr) | |
3357 | { | |
3358 | unsigned i, j; | |
3359 | ||
3360 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3361 | { | |
3362 | subscript_p sub = DDR_SUBSCRIPT (ddr, i); | |
3363 | conflict_function *ca = SUB_CONFLICTS_IN_A (sub); | |
3364 | conflict_function *cb = SUB_CONFLICTS_IN_B (sub); | |
3365 | ||
3366 | for (j = 0; j < ca->n; j++) | |
3367 | if (affine_function_zero_p (ca->fns[j])) | |
3368 | { | |
3369 | insert_innermost_unit_dist_vector (ddr); | |
3370 | return; | |
3371 | } | |
3372 | ||
3373 | for (j = 0; j < cb->n; j++) | |
3374 | if (affine_function_zero_p (cb->fns[j])) | |
3375 | { | |
3376 | insert_innermost_unit_dist_vector (ddr); | |
3377 | return; | |
3378 | } | |
3379 | } | |
3380 | } | |
3381 | ||
b44d1046 | 3382 | /* Compute the classic per loop distance vector. DDR is the data |
3383 | dependence relation to build a vector from. Return false when fail | |
3384 | to represent the data dependence as a distance vector. */ | |
2146e26d | 3385 | |
557ef5d8 | 3386 | static bool |
8c7b1d8e | 3387 | build_classic_dist_vector (struct data_dependence_relation *ddr, |
3388 | struct loop *loop_nest) | |
2146e26d | 3389 | { |
1532ec98 | 3390 | bool init_b = false; |
b44d1046 | 3391 | int index_carry = DDR_NB_LOOPS (ddr); |
3392 | lambda_vector dist_v; | |
1532ec98 | 3393 | |
6b6f234c | 3394 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
d534eb36 | 3395 | return false; |
b44d1046 | 3396 | |
3397 | if (same_access_functions (ddr)) | |
2146e26d | 3398 | { |
b44d1046 | 3399 | /* Save the 0 vector. */ |
3400 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3401 | save_dist_v (ddr, dist_v); | |
2146e26d | 3402 | |
2a21a5df | 3403 | if (constant_access_functions (ddr)) |
3404 | add_distance_for_zero_overlaps (ddr); | |
3405 | ||
b44d1046 | 3406 | if (DDR_NB_LOOPS (ddr) > 1) |
3407 | add_other_self_distances (ddr); | |
bc3c8ad4 | 3408 | |
b44d1046 | 3409 | return true; |
3410 | } | |
bc3c8ad4 | 3411 | |
b44d1046 | 3412 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3413 | if (!build_classic_dist_vector_1 (ddr, DDR_A (ddr), DDR_B (ddr), | |
3414 | dist_v, &init_b, &index_carry)) | |
3415 | return false; | |
bc3c8ad4 | 3416 | |
b44d1046 | 3417 | /* Save the distance vector if we initialized one. */ |
3418 | if (init_b) | |
3419 | { | |
3420 | /* Verify a basic constraint: classic distance vectors should | |
3421 | always be lexicographically positive. | |
3422 | ||
3423 | Data references are collected in the order of execution of | |
3424 | the program, thus for the following loop | |
3425 | ||
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 | ||
3433 | references are collected following the direction of the wind: | |
3434 | A then B. The data dependence tests are performed also | |
3435 | following this order, such that we're looking at the distance | |
3436 | separating the elements accessed by A from the elements later | |
3437 | accessed by B. But in this example, the distance returned by | |
3438 | test_dep (A, B) is lexicographically negative (-1, 1), that | |
3439 | means that the access A occurs later than B with respect to | |
3440 | the outer loop, ie. we're actually looking upwind. In this | |
3441 | case we solve test_dep (B, A) looking downwind to the | |
3442 | lexicographically positive solution, that returns the | |
3443 | distance vector (1, -1). */ | |
3444 | if (!lambda_vector_lexico_pos (dist_v, DDR_NB_LOOPS (ddr))) | |
3445 | { | |
3446 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
d534eb36 | 3447 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3448 | loop_nest)) | |
3449 | return false; | |
b44d1046 | 3450 | compute_subscript_distance (ddr); |
d534eb36 | 3451 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3452 | save_v, &init_b, &index_carry)) | |
3453 | return false; | |
b44d1046 | 3454 | save_dist_v (ddr, save_v); |
0ecb94cf | 3455 | DDR_REVERSED_P (ddr) = true; |
b44d1046 | 3456 | |
3457 | /* In this case there is a dependence forward for all the | |
3458 | outer loops: | |
3459 | ||
3460 | | for (k = 1; k < 100; k++) | |
3461 | | for (i = 1; i < 100; i++) | |
3462 | | for (j = 1; j < 100; j++) | |
3463 | | { | |
3464 | | t = T[j+1][i-1]; // A | |
3465 | | T[j][i] = t + 2; // B | |
3466 | | } | |
3467 | ||
48e1416a | 3468 | the vectors are: |
b44d1046 | 3469 | (0, 1, -1) |
3470 | (1, 1, -1) | |
3471 | (1, -1, 1) | |
3472 | */ | |
3473 | if (DDR_NB_LOOPS (ddr) > 1) | |
3474 | { | |
3475 | add_outer_distances (ddr, save_v, index_carry); | |
3476 | add_outer_distances (ddr, dist_v, index_carry); | |
bc3c8ad4 | 3477 | } |
b44d1046 | 3478 | } |
3479 | else | |
3480 | { | |
3481 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3482 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
bc3c8ad4 | 3483 | |
b44d1046 | 3484 | if (DDR_NB_LOOPS (ddr) > 1) |
2146e26d | 3485 | { |
b44d1046 | 3486 | lambda_vector opposite_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
bc3c8ad4 | 3487 | |
d534eb36 | 3488 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), |
3489 | DDR_A (ddr), loop_nest)) | |
3490 | return false; | |
b44d1046 | 3491 | compute_subscript_distance (ddr); |
d534eb36 | 3492 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3493 | opposite_v, &init_b, | |
3494 | &index_carry)) | |
3495 | return false; | |
bc3c8ad4 | 3496 | |
d534eb36 | 3497 | save_dist_v (ddr, save_v); |
b44d1046 | 3498 | add_outer_distances (ddr, dist_v, index_carry); |
3499 | add_outer_distances (ddr, opposite_v, index_carry); | |
2146e26d | 3500 | } |
d534eb36 | 3501 | else |
3502 | save_dist_v (ddr, save_v); | |
2146e26d | 3503 | } |
3504 | } | |
b44d1046 | 3505 | else |
3506 | { | |
3507 | /* There is a distance of 1 on all the outer loops: Example: | |
3508 | there is a dependence of distance 1 on loop_1 for the array A. | |
1532ec98 | 3509 | |
b44d1046 | 3510 | | loop_1 |
3511 | | A[5] = ... | |
3512 | | endloop | |
3513 | */ | |
3514 | add_outer_distances (ddr, dist_v, | |
3515 | lambda_vector_first_nz (dist_v, | |
3516 | DDR_NB_LOOPS (ddr), 0)); | |
3517 | } | |
3518 | ||
3519 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1532ec98 | 3520 | { |
b44d1046 | 3521 | unsigned i; |
1532ec98 | 3522 | |
b44d1046 | 3523 | fprintf (dump_file, "(build_classic_dist_vector\n"); |
3524 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3525 | { | |
3526 | fprintf (dump_file, " dist_vector = ("); | |
3527 | print_lambda_vector (dump_file, DDR_DIST_VECT (ddr, i), | |
3528 | DDR_NB_LOOPS (ddr)); | |
3529 | fprintf (dump_file, " )\n"); | |
3530 | } | |
3531 | fprintf (dump_file, ")\n"); | |
1532ec98 | 3532 | } |
3533 | ||
b44d1046 | 3534 | return true; |
3535 | } | |
2146e26d | 3536 | |
b44d1046 | 3537 | /* Return the direction for a given distance. |
3538 | FIXME: Computing dir this way is suboptimal, since dir can catch | |
3539 | cases that dist is unable to represent. */ | |
bc3c8ad4 | 3540 | |
b44d1046 | 3541 | static inline enum data_dependence_direction |
3542 | dir_from_dist (int dist) | |
3543 | { | |
3544 | if (dist > 0) | |
3545 | return dir_positive; | |
3546 | else if (dist < 0) | |
3547 | return dir_negative; | |
3548 | else | |
3549 | return dir_equal; | |
3550 | } | |
1532ec98 | 3551 | |
b44d1046 | 3552 | /* Compute the classic per loop direction vector. DDR is the data |
3553 | dependence relation to build a vector from. */ | |
1532ec98 | 3554 | |
b44d1046 | 3555 | static void |
3556 | build_classic_dir_vector (struct data_dependence_relation *ddr) | |
3557 | { | |
3558 | unsigned i, j; | |
3559 | lambda_vector dist_v; | |
bc3c8ad4 | 3560 | |
f1f41a6c | 3561 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, dist_v) |
b44d1046 | 3562 | { |
3563 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
bc3c8ad4 | 3564 | |
b44d1046 | 3565 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) |
3566 | dir_v[j] = dir_from_dist (dist_v[j]); | |
1532ec98 | 3567 | |
b44d1046 | 3568 | save_dir_v (ddr, dir_v); |
3569 | } | |
2146e26d | 3570 | } |
3571 | ||
b44d1046 | 3572 | /* Helper function. Returns true when there is a dependence between |
3573 | data references DRA and DRB. */ | |
6b421feb | 3574 | |
b44d1046 | 3575 | static bool |
3576 | subscript_dependence_tester_1 (struct data_dependence_relation *ddr, | |
3577 | struct data_reference *dra, | |
8c7b1d8e | 3578 | struct data_reference *drb, |
3579 | struct loop *loop_nest) | |
6b421feb | 3580 | { |
3581 | unsigned int i; | |
6b421feb | 3582 | tree last_conflicts; |
41c7a324 | 3583 | struct subscript *subscript; |
2ecb06bc | 3584 | tree res = NULL_TREE; |
b44d1046 | 3585 | |
f1f41a6c | 3586 | for (i = 0; DDR_SUBSCRIPTS (ddr).iterate (i, &subscript); i++) |
6b421feb | 3587 | { |
87da4f2e | 3588 | conflict_function *overlaps_a, *overlaps_b; |
41c7a324 | 3589 | |
48e1416a | 3590 | analyze_overlapping_iterations (DR_ACCESS_FN (dra, i), |
6b421feb | 3591 | DR_ACCESS_FN (drb, i), |
48e1416a | 3592 | &overlaps_a, &overlaps_b, |
8c7b1d8e | 3593 | &last_conflicts, loop_nest); |
41c7a324 | 3594 | |
2ecb06bc | 3595 | if (SUB_CONFLICTS_IN_A (subscript)) |
3596 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
3597 | if (SUB_CONFLICTS_IN_B (subscript)) | |
3598 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
3599 | ||
3600 | SUB_CONFLICTS_IN_A (subscript) = overlaps_a; | |
3601 | SUB_CONFLICTS_IN_B (subscript) = overlaps_b; | |
3602 | SUB_LAST_CONFLICT (subscript) = last_conflicts; | |
3603 | ||
3604 | /* If there is any undetermined conflict function we have to | |
3605 | give a conservative answer in case we cannot prove that | |
3606 | no dependence exists when analyzing another subscript. */ | |
87da4f2e | 3607 | if (CF_NOT_KNOWN_P (overlaps_a) |
3608 | || CF_NOT_KNOWN_P (overlaps_b)) | |
6b421feb | 3609 | { |
2ecb06bc | 3610 | res = chrec_dont_know; |
3611 | continue; | |
6b421feb | 3612 | } |
41c7a324 | 3613 | |
2ecb06bc | 3614 | /* When there is a subscript with no dependence we can stop. */ |
87da4f2e | 3615 | else if (CF_NO_DEPENDENCE_P (overlaps_a) |
3616 | || CF_NO_DEPENDENCE_P (overlaps_b)) | |
6b421feb | 3617 | { |
2ecb06bc | 3618 | res = chrec_known; |
3619 | break; | |
6b421feb | 3620 | } |
3621 | } | |
3622 | ||
2ecb06bc | 3623 | if (res == NULL_TREE) |
3624 | return true; | |
3625 | ||
3626 | if (res == chrec_known) | |
3627 | dependence_stats.num_dependence_independent++; | |
3628 | else | |
3629 | dependence_stats.num_dependence_undetermined++; | |
3630 | finalize_ddr_dependent (ddr, res); | |
3631 | return false; | |
b44d1046 | 3632 | } |
3633 | ||
8c7b1d8e | 3634 | /* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */ |
b44d1046 | 3635 | |
3636 | static void | |
8c7b1d8e | 3637 | subscript_dependence_tester (struct data_dependence_relation *ddr, |
3638 | struct loop *loop_nest) | |
b44d1046 | 3639 | { |
8c7b1d8e | 3640 | if (subscript_dependence_tester_1 (ddr, DDR_A (ddr), DDR_B (ddr), loop_nest)) |
b44d1046 | 3641 | dependence_stats.num_dependence_dependent++; |
6b421feb | 3642 | |
6b421feb | 3643 | compute_subscript_distance (ddr); |
8c7b1d8e | 3644 | if (build_classic_dist_vector (ddr, loop_nest)) |
b44d1046 | 3645 | build_classic_dir_vector (ddr); |
6b421feb | 3646 | } |
3647 | ||
2146e26d | 3648 | /* Returns true when all the access functions of A are affine or |
8c7b1d8e | 3649 | constant with respect to LOOP_NEST. */ |
2146e26d | 3650 | |
48e1416a | 3651 | static bool |
7ecb5bb2 | 3652 | access_functions_are_affine_or_constant_p (const struct data_reference *a, |
3653 | const struct loop *loop_nest) | |
2146e26d | 3654 | { |
3655 | unsigned int i; | |
f1f41a6c | 3656 | vec<tree> fns = DR_ACCESS_FNS (a); |
e38f1ca4 | 3657 | tree t; |
355572cc | 3658 | |
f1f41a6c | 3659 | FOR_EACH_VEC_ELT (fns, i, t) |
8c7b1d8e | 3660 | if (!evolution_function_is_invariant_p (t, loop_nest->num) |
3661 | && !evolution_function_is_affine_multivariate_p (t, loop_nest->num)) | |
2146e26d | 3662 | return false; |
48e1416a | 3663 | |
2146e26d | 3664 | return true; |
3665 | } | |
3666 | ||
355572cc | 3667 | /* Initializes an equation for an OMEGA problem using the information |
3668 | contained in the ACCESS_FUN. Returns true when the operation | |
3669 | succeeded. | |
3670 | ||
3671 | PB is the omega constraint system. | |
3672 | EQ is the number of the equation to be initialized. | |
3673 | OFFSET is used for shifting the variables names in the constraints: | |
3674 | a constrain is composed of 2 * the number of variables surrounding | |
3675 | dependence accesses. OFFSET is set either to 0 for the first n variables, | |
3676 | then it is set to n. | |
3677 | ACCESS_FUN is expected to be an affine chrec. */ | |
3678 | ||
3679 | static bool | |
48e1416a | 3680 | init_omega_eq_with_af (omega_pb pb, unsigned eq, |
3681 | unsigned int offset, tree access_fun, | |
355572cc | 3682 | struct data_dependence_relation *ddr) |
3683 | { | |
3684 | switch (TREE_CODE (access_fun)) | |
3685 | { | |
3686 | case POLYNOMIAL_CHREC: | |
3687 | { | |
3688 | tree left = CHREC_LEFT (access_fun); | |
3689 | tree right = CHREC_RIGHT (access_fun); | |
3690 | int var = CHREC_VARIABLE (access_fun); | |
3691 | unsigned var_idx; | |
3692 | ||
3693 | if (TREE_CODE (right) != INTEGER_CST) | |
3694 | return false; | |
3695 | ||
3696 | var_idx = index_in_loop_nest (var, DDR_LOOP_NEST (ddr)); | |
58f77a87 | 3697 | pb->eqs[eq].coef[offset + var_idx + 1] = int_cst_value (right); |
355572cc | 3698 | |
3699 | /* Compute the innermost loop index. */ | |
3700 | DDR_INNER_LOOP (ddr) = MAX (DDR_INNER_LOOP (ddr), var_idx); | |
3701 | ||
3702 | if (offset == 0) | |
48e1416a | 3703 | pb->eqs[eq].coef[var_idx + DDR_NB_LOOPS (ddr) + 1] |
58f77a87 | 3704 | += int_cst_value (right); |
355572cc | 3705 | |
3706 | switch (TREE_CODE (left)) | |
3707 | { | |
3708 | case POLYNOMIAL_CHREC: | |
3709 | return init_omega_eq_with_af (pb, eq, offset, left, ddr); | |
3710 | ||
3711 | case INTEGER_CST: | |
58f77a87 | 3712 | pb->eqs[eq].coef[0] += int_cst_value (left); |
355572cc | 3713 | return true; |
3714 | ||
3715 | default: | |
3716 | return false; | |
3717 | } | |
3718 | } | |
3719 | ||
3720 | case INTEGER_CST: | |
58f77a87 | 3721 | pb->eqs[eq].coef[0] += int_cst_value (access_fun); |
355572cc | 3722 | return true; |
3723 | ||
3724 | default: | |
3725 | return false; | |
3726 | } | |
3727 | } | |
3728 | ||
3729 | /* As explained in the comments preceding init_omega_for_ddr, we have | |
3730 | to set up a system for each loop level, setting outer loops | |
3731 | variation to zero, and current loop variation to positive or zero. | |
3732 | Save each lexico positive distance vector. */ | |
3733 | ||
3734 | static void | |
3735 | omega_extract_distance_vectors (omega_pb pb, | |
3736 | struct data_dependence_relation *ddr) | |
3737 | { | |
3738 | int eq, geq; | |
3739 | unsigned i, j; | |
3740 | struct loop *loopi, *loopj; | |
3741 | enum omega_result res; | |
3742 | ||
3743 | /* Set a new problem for each loop in the nest. The basis is the | |
3744 | problem that we have initialized until now. On top of this we | |
3745 | add new constraints. */ | |
48e1416a | 3746 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
f1f41a6c | 3747 | && DDR_LOOP_NEST (ddr).iterate (i, &loopi); i++) |
355572cc | 3748 | { |
3749 | int dist = 0; | |
3750 | omega_pb copy = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), | |
3751 | DDR_NB_LOOPS (ddr)); | |
3752 | ||
3753 | omega_copy_problem (copy, pb); | |
3754 | ||
3755 | /* For all the outer loops "loop_j", add "dj = 0". */ | |
f1f41a6c | 3756 | for (j = 0; j < i && DDR_LOOP_NEST (ddr).iterate (j, &loopj); j++) |
355572cc | 3757 | { |
3758 | eq = omega_add_zero_eq (copy, omega_black); | |
3759 | copy->eqs[eq].coef[j + 1] = 1; | |
3760 | } | |
3761 | ||
3762 | /* For "loop_i", add "0 <= di". */ | |
3763 | geq = omega_add_zero_geq (copy, omega_black); | |
3764 | copy->geqs[geq].coef[i + 1] = 1; | |
3765 | ||
3766 | /* Reduce the constraint system, and test that the current | |
3767 | problem is feasible. */ | |
3768 | res = omega_simplify_problem (copy); | |
48e1416a | 3769 | if (res == omega_false |
355572cc | 3770 | || res == omega_unknown |
3771 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3772 | goto next_problem; | |
3773 | ||
3774 | for (eq = 0; eq < copy->num_subs; eq++) | |
3775 | if (copy->subs[eq].key == (int) i + 1) | |
3776 | { | |
3777 | dist = copy->subs[eq].coef[0]; | |
3778 | goto found_dist; | |
3779 | } | |
3780 | ||
3781 | if (dist == 0) | |
3782 | { | |
3783 | /* Reinitialize problem... */ | |
3784 | omega_copy_problem (copy, pb); | |
f1f41a6c | 3785 | for (j = 0; j < i && DDR_LOOP_NEST (ddr).iterate (j, &loopj); j++) |
355572cc | 3786 | { |
3787 | eq = omega_add_zero_eq (copy, omega_black); | |
3788 | copy->eqs[eq].coef[j + 1] = 1; | |
3789 | } | |
3790 | ||
3791 | /* ..., but this time "di = 1". */ | |
3792 | eq = omega_add_zero_eq (copy, omega_black); | |
3793 | copy->eqs[eq].coef[i + 1] = 1; | |
3794 | copy->eqs[eq].coef[0] = -1; | |
3795 | ||
3796 | res = omega_simplify_problem (copy); | |
48e1416a | 3797 | if (res == omega_false |
355572cc | 3798 | || res == omega_unknown |
3799 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3800 | goto next_problem; | |
3801 | ||
3802 | for (eq = 0; eq < copy->num_subs; eq++) | |
3803 | if (copy->subs[eq].key == (int) i + 1) | |
3804 | { | |
3805 | dist = copy->subs[eq].coef[0]; | |
3806 | goto found_dist; | |
3807 | } | |
3808 | } | |
3809 | ||
3810 | found_dist:; | |
3811 | /* Save the lexicographically positive distance vector. */ | |
3812 | if (dist >= 0) | |
3813 | { | |
3814 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3815 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3816 | ||
3817 | dist_v[i] = dist; | |
3818 | ||
3819 | for (eq = 0; eq < copy->num_subs; eq++) | |
3820 | if (copy->subs[eq].key > 0) | |
3821 | { | |
3822 | dist = copy->subs[eq].coef[0]; | |
3823 | dist_v[copy->subs[eq].key - 1] = dist; | |
3824 | } | |
3825 | ||
3826 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3827 | dir_v[j] = dir_from_dist (dist_v[j]); | |
3828 | ||
3829 | save_dist_v (ddr, dist_v); | |
3830 | save_dir_v (ddr, dir_v); | |
3831 | } | |
3832 | ||
3833 | next_problem:; | |
3834 | omega_free_problem (copy); | |
3835 | } | |
3836 | } | |
3837 | ||
3838 | /* This is called for each subscript of a tuple of data references: | |
3839 | insert an equality for representing the conflicts. */ | |
3840 | ||
3841 | static bool | |
3842 | omega_setup_subscript (tree access_fun_a, tree access_fun_b, | |
3843 | struct data_dependence_relation *ddr, | |
3844 | omega_pb pb, bool *maybe_dependent) | |
3845 | { | |
3846 | int eq; | |
9a3dad1c | 3847 | tree type = signed_type_for_types (TREE_TYPE (access_fun_a), |
3848 | TREE_TYPE (access_fun_b)); | |
75a70cf9 | 3849 | tree fun_a = chrec_convert (type, access_fun_a, NULL); |
3850 | tree fun_b = chrec_convert (type, access_fun_b, NULL); | |
9a3dad1c | 3851 | tree difference = chrec_fold_minus (type, fun_a, fun_b); |
ff2cd6d1 | 3852 | tree minus_one; |
355572cc | 3853 | |
3854 | /* When the fun_a - fun_b is not constant, the dependence is not | |
3855 | captured by the classic distance vector representation. */ | |
3856 | if (TREE_CODE (difference) != INTEGER_CST) | |
3857 | return false; | |
3858 | ||
3859 | /* ZIV test. */ | |
3860 | if (ziv_subscript_p (fun_a, fun_b) && !integer_zerop (difference)) | |
3861 | { | |
3862 | /* There is no dependence. */ | |
3863 | *maybe_dependent = false; | |
3864 | return true; | |
3865 | } | |
3866 | ||
ff2cd6d1 | 3867 | minus_one = build_int_cst (type, -1); |
3868 | fun_b = chrec_fold_multiply (type, fun_b, minus_one); | |
355572cc | 3869 | |
3870 | eq = omega_add_zero_eq (pb, omega_black); | |
3871 | if (!init_omega_eq_with_af (pb, eq, DDR_NB_LOOPS (ddr), fun_a, ddr) | |
3872 | || !init_omega_eq_with_af (pb, eq, 0, fun_b, ddr)) | |
3873 | /* There is probably a dependence, but the system of | |
3874 | constraints cannot be built: answer "don't know". */ | |
3875 | return false; | |
3876 | ||
3877 | /* GCD test. */ | |
3878 | if (DDR_NB_LOOPS (ddr) != 0 && pb->eqs[eq].coef[0] | |
48e1416a | 3879 | && !int_divides_p (lambda_vector_gcd |
355572cc | 3880 | ((lambda_vector) &(pb->eqs[eq].coef[1]), |
3881 | 2 * DDR_NB_LOOPS (ddr)), | |
3882 | pb->eqs[eq].coef[0])) | |
3883 | { | |
3884 | /* There is no dependence. */ | |
3885 | *maybe_dependent = false; | |
3886 | return true; | |
3887 | } | |
3888 | ||
3889 | return true; | |
3890 | } | |
3891 | ||
3892 | /* Helper function, same as init_omega_for_ddr but specialized for | |
3893 | data references A and B. */ | |
3894 | ||
3895 | static bool | |
3896 | init_omega_for_ddr_1 (struct data_reference *dra, struct data_reference *drb, | |
3897 | struct data_dependence_relation *ddr, | |
3898 | omega_pb pb, bool *maybe_dependent) | |
3899 | { | |
3900 | unsigned i; | |
3901 | int ineq; | |
3902 | struct loop *loopi; | |
3903 | unsigned nb_loops = DDR_NB_LOOPS (ddr); | |
3904 | ||
3905 | /* Insert an equality per subscript. */ | |
3906 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3907 | { | |
3908 | if (!omega_setup_subscript (DR_ACCESS_FN (dra, i), DR_ACCESS_FN (drb, i), | |
3909 | ddr, pb, maybe_dependent)) | |
3910 | return false; | |
3911 | else if (*maybe_dependent == false) | |
3912 | { | |
3913 | /* There is no dependence. */ | |
3914 | DDR_ARE_DEPENDENT (ddr) = chrec_known; | |
3915 | return true; | |
3916 | } | |
3917 | } | |
3918 | ||
3919 | /* Insert inequalities: constraints corresponding to the iteration | |
3920 | domain, i.e. the loops surrounding the references "loop_x" and | |
3921 | the distance variables "dx". The layout of the OMEGA | |
3922 | representation is as follows: | |
3923 | - coef[0] is the constant | |
3924 | - coef[1..nb_loops] are the protected variables that will not be | |
3925 | removed by the solver: the "dx" | |
3926 | - coef[nb_loops + 1, 2*nb_loops] are the loop variables: "loop_x". | |
3927 | */ | |
48e1416a | 3928 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
f1f41a6c | 3929 | && DDR_LOOP_NEST (ddr).iterate (i, &loopi); i++) |
355572cc | 3930 | { |
fee017b3 | 3931 | HOST_WIDE_INT nbi = max_stmt_executions_int (loopi); |
355572cc | 3932 | |
3933 | /* 0 <= loop_x */ | |
3934 | ineq = omega_add_zero_geq (pb, omega_black); | |
3935 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3936 | ||
3937 | /* 0 <= loop_x + dx */ | |
3938 | ineq = omega_add_zero_geq (pb, omega_black); | |
3939 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3940 | pb->geqs[ineq].coef[i + 1] = 1; | |
3941 | ||
3942 | if (nbi != -1) | |
3943 | { | |
3944 | /* loop_x <= nb_iters */ | |
3945 | ineq = omega_add_zero_geq (pb, omega_black); | |
3946 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3947 | pb->geqs[ineq].coef[0] = nbi; | |
3948 | ||
3949 | /* loop_x + dx <= nb_iters */ | |
3950 | ineq = omega_add_zero_geq (pb, omega_black); | |
3951 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3952 | pb->geqs[ineq].coef[i + 1] = -1; | |
3953 | pb->geqs[ineq].coef[0] = nbi; | |
3954 | ||
3955 | /* A step "dx" bigger than nb_iters is not feasible, so | |
3956 | add "0 <= nb_iters + dx", */ | |
3957 | ineq = omega_add_zero_geq (pb, omega_black); | |
3958 | pb->geqs[ineq].coef[i + 1] = 1; | |
3959 | pb->geqs[ineq].coef[0] = nbi; | |
3960 | /* and "dx <= nb_iters". */ | |
3961 | ineq = omega_add_zero_geq (pb, omega_black); | |
3962 | pb->geqs[ineq].coef[i + 1] = -1; | |
3963 | pb->geqs[ineq].coef[0] = nbi; | |
3964 | } | |
3965 | } | |
3966 | ||
3967 | omega_extract_distance_vectors (pb, ddr); | |
3968 | ||
3969 | return true; | |
3970 | } | |
3971 | ||
3972 | /* Sets up the Omega dependence problem for the data dependence | |
3973 | relation DDR. Returns false when the constraint system cannot be | |
3974 | built, ie. when the test answers "don't know". Returns true | |
3975 | otherwise, and when independence has been proved (using one of the | |
3976 | trivial dependence test), set MAYBE_DEPENDENT to false, otherwise | |
3977 | set MAYBE_DEPENDENT to true. | |
3978 | ||
3979 | Example: for setting up the dependence system corresponding to the | |
48e1416a | 3980 | conflicting accesses |
355572cc | 3981 | |
3982 | | loop_i | |
3983 | | loop_j | |
3984 | | A[i, i+1] = ... | |
3985 | | ... A[2*j, 2*(i + j)] | |
3986 | | endloop_j | |
3987 | | endloop_i | |
48e1416a | 3988 | |
355572cc | 3989 | the following constraints come from the iteration domain: |
3990 | ||
3991 | 0 <= i <= Ni | |
3992 | 0 <= i + di <= Ni | |
3993 | 0 <= j <= Nj | |
3994 | 0 <= j + dj <= Nj | |
3995 | ||
3996 | where di, dj are the distance variables. The constraints | |
3997 | representing the conflicting elements are: | |
3998 | ||
3999 | i = 2 * (j + dj) | |
4000 | i + 1 = 2 * (i + di + j + dj) | |
4001 | ||
4002 | For asking that the resulting distance vector (di, dj) be | |
4003 | lexicographically positive, we insert the constraint "di >= 0". If | |
4004 | "di = 0" in the solution, we fix that component to zero, and we | |
4005 | look at the inner loops: we set a new problem where all the outer | |
4006 | loop distances are zero, and fix this inner component to be | |
4007 | positive. When one of the components is positive, we save that | |
4008 | distance, and set a new problem where the distance on this loop is | |
4009 | zero, searching for other distances in the inner loops. Here is | |
4010 | the classic example that illustrates that we have to set for each | |
4011 | inner loop a new problem: | |
4012 | ||
4013 | | loop_1 | |
4014 | | loop_2 | |
4015 | | A[10] | |
4016 | | endloop_2 | |
4017 | | endloop_1 | |
4018 | ||
4019 | we have to save two distances (1, 0) and (0, 1). | |
4020 | ||
4021 | Given two array references, refA and refB, we have to set the | |
4022 | dependence problem twice, refA vs. refB and refB vs. refA, and we | |
4023 | cannot do a single test, as refB might occur before refA in the | |
4024 | inner loops, and the contrary when considering outer loops: ex. | |
4025 | ||
4026 | | loop_0 | |
4027 | | loop_1 | |
4028 | | loop_2 | |
4029 | | T[{1,+,1}_2][{1,+,1}_1] // refA | |
4030 | | T[{2,+,1}_2][{0,+,1}_1] // refB | |
4031 | | endloop_2 | |
4032 | | endloop_1 | |
4033 | | endloop_0 | |
4034 | ||
4035 | refB touches the elements in T before refA, and thus for the same | |
4036 | loop_0 refB precedes refA: ie. the distance vector (0, 1, -1) | |
4037 | but for successive loop_0 iterations, we have (1, -1, 1) | |
4038 | ||
4039 | The Omega solver expects the distance variables ("di" in the | |
4040 | previous example) to come first in the constraint system (as | |
4041 | variables to be protected, or "safe" variables), the constraint | |
4042 | system is built using the following layout: | |
4043 | ||
4044 | "cst | distance vars | index vars". | |
4045 | */ | |
4046 | ||
4047 | static bool | |
4048 | init_omega_for_ddr (struct data_dependence_relation *ddr, | |
4049 | bool *maybe_dependent) | |
4050 | { | |
4051 | omega_pb pb; | |
4052 | bool res = false; | |
4053 | ||
4054 | *maybe_dependent = true; | |
4055 | ||
4056 | if (same_access_functions (ddr)) | |
4057 | { | |
4058 | unsigned j; | |
4059 | lambda_vector dir_v; | |
4060 | ||
4061 | /* Save the 0 vector. */ | |
4062 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
4063 | dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
4064 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
4065 | dir_v[j] = dir_equal; | |
4066 | save_dir_v (ddr, dir_v); | |
4067 | ||
4068 | /* Save the dependences carried by outer loops. */ | |
4069 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4070 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
4071 | maybe_dependent); | |
4072 | omega_free_problem (pb); | |
4073 | return res; | |
4074 | } | |
4075 | ||
4076 | /* Omega expects the protected variables (those that have to be kept | |
4077 | after elimination) to appear first in the constraint system. | |
4078 | These variables are the distance variables. In the following | |
4079 | initialization we declare NB_LOOPS safe variables, and the total | |
4080 | number of variables for the constraint system is 2*NB_LOOPS. */ | |
4081 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4082 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
4083 | maybe_dependent); | |
4084 | omega_free_problem (pb); | |
4085 | ||
4086 | /* Stop computation if not decidable, or no dependence. */ | |
4087 | if (res == false || *maybe_dependent == false) | |
4088 | return res; | |
4089 | ||
4090 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4091 | res = init_omega_for_ddr_1 (DDR_B (ddr), DDR_A (ddr), ddr, pb, | |
4092 | maybe_dependent); | |
4093 | omega_free_problem (pb); | |
4094 | ||
4095 | return res; | |
4096 | } | |
4097 | ||
4098 | /* Return true when DDR contains the same information as that stored | |
4099 | in DIR_VECTS and in DIST_VECTS, return false otherwise. */ | |
4100 | ||
4101 | static bool | |
4102 | ddr_consistent_p (FILE *file, | |
4103 | struct data_dependence_relation *ddr, | |
f1f41a6c | 4104 | vec<lambda_vector> dist_vects, |
4105 | vec<lambda_vector> dir_vects) | |
355572cc | 4106 | { |
4107 | unsigned int i, j; | |
4108 | ||
4109 | /* If dump_file is set, output there. */ | |
4110 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4111 | file = dump_file; | |
4112 | ||
f1f41a6c | 4113 | if (dist_vects.length () != DDR_NUM_DIST_VECTS (ddr)) |
355572cc | 4114 | { |
4115 | lambda_vector b_dist_v; | |
4116 | fprintf (file, "\n(Number of distance vectors differ: Banerjee has %d, Omega has %d.\n", | |
f1f41a6c | 4117 | dist_vects.length (), |
355572cc | 4118 | DDR_NUM_DIST_VECTS (ddr)); |
4119 | ||
4120 | fprintf (file, "Banerjee dist vectors:\n"); | |
f1f41a6c | 4121 | FOR_EACH_VEC_ELT (dist_vects, i, b_dist_v) |
355572cc | 4122 | print_lambda_vector (file, b_dist_v, DDR_NB_LOOPS (ddr)); |
4123 | ||
4124 | fprintf (file, "Omega dist vectors:\n"); | |
4125 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
4126 | print_lambda_vector (file, DDR_DIST_VECT (ddr, i), DDR_NB_LOOPS (ddr)); | |
4127 | ||
4128 | fprintf (file, "data dependence relation:\n"); | |
4129 | dump_data_dependence_relation (file, ddr); | |
4130 | ||
4131 | fprintf (file, ")\n"); | |
4132 | return false; | |
4133 | } | |
4134 | ||
f1f41a6c | 4135 | if (dir_vects.length () != DDR_NUM_DIR_VECTS (ddr)) |
355572cc | 4136 | { |
4137 | fprintf (file, "\n(Number of direction vectors differ: Banerjee has %d, Omega has %d.)\n", | |
f1f41a6c | 4138 | dir_vects.length (), |
355572cc | 4139 | DDR_NUM_DIR_VECTS (ddr)); |
4140 | return false; | |
4141 | } | |
4142 | ||
4143 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
4144 | { | |
4145 | lambda_vector a_dist_v; | |
4146 | lambda_vector b_dist_v = DDR_DIST_VECT (ddr, i); | |
4147 | ||
4148 | /* Distance vectors are not ordered in the same way in the DDR | |
4149 | and in the DIST_VECTS: search for a matching vector. */ | |
f1f41a6c | 4150 | FOR_EACH_VEC_ELT (dist_vects, j, a_dist_v) |
355572cc | 4151 | if (lambda_vector_equal (a_dist_v, b_dist_v, DDR_NB_LOOPS (ddr))) |
4152 | break; | |
4153 | ||
f1f41a6c | 4154 | if (j == dist_vects.length ()) |
355572cc | 4155 | { |
4156 | fprintf (file, "\n(Dist vectors from the first dependence analyzer:\n"); | |
4157 | print_dist_vectors (file, dist_vects, DDR_NB_LOOPS (ddr)); | |
4158 | fprintf (file, "not found in Omega dist vectors:\n"); | |
4159 | print_dist_vectors (file, DDR_DIST_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4160 | fprintf (file, "data dependence relation:\n"); | |
4161 | dump_data_dependence_relation (file, ddr); | |
4162 | fprintf (file, ")\n"); | |
4163 | } | |
4164 | } | |
4165 | ||
4166 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
4167 | { | |
4168 | lambda_vector a_dir_v; | |
4169 | lambda_vector b_dir_v = DDR_DIR_VECT (ddr, i); | |
4170 | ||
4171 | /* Direction vectors are not ordered in the same way in the DDR | |
4172 | and in the DIR_VECTS: search for a matching vector. */ | |
f1f41a6c | 4173 | FOR_EACH_VEC_ELT (dir_vects, j, a_dir_v) |
355572cc | 4174 | if (lambda_vector_equal (a_dir_v, b_dir_v, DDR_NB_LOOPS (ddr))) |
4175 | break; | |
4176 | ||
f1f41a6c | 4177 | if (j == dist_vects.length ()) |
355572cc | 4178 | { |
4179 | fprintf (file, "\n(Dir vectors from the first dependence analyzer:\n"); | |
4180 | print_dir_vectors (file, dir_vects, DDR_NB_LOOPS (ddr)); | |
4181 | fprintf (file, "not found in Omega dir vectors:\n"); | |
4182 | print_dir_vectors (file, DDR_DIR_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4183 | fprintf (file, "data dependence relation:\n"); | |
4184 | dump_data_dependence_relation (file, ddr); | |
4185 | fprintf (file, ")\n"); | |
4186 | } | |
4187 | } | |
4188 | ||
48e1416a | 4189 | return true; |
355572cc | 4190 | } |
4191 | ||
8c7b1d8e | 4192 | /* This computes the affine dependence relation between A and B with |
4193 | respect to LOOP_NEST. CHREC_KNOWN is used for representing the | |
4194 | independence between two accesses, while CHREC_DONT_KNOW is used | |
4195 | for representing the unknown relation. | |
48e1416a | 4196 | |
2146e26d | 4197 | Note that it is possible to stop the computation of the dependence |
4198 | relation the first time we detect a CHREC_KNOWN element for a given | |
4199 | subscript. */ | |
4200 | ||
7b6f8db4 | 4201 | void |
8c7b1d8e | 4202 | compute_affine_dependence (struct data_dependence_relation *ddr, |
4203 | struct loop *loop_nest) | |
2146e26d | 4204 | { |
4205 | struct data_reference *dra = DDR_A (ddr); | |
4206 | struct data_reference *drb = DDR_B (ddr); | |
48e1416a | 4207 | |
2146e26d | 4208 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4209 | { | |
6b6f234c | 4210 | fprintf (dump_file, "(compute_affine_dependence\n"); |
95539e1d | 4211 | fprintf (dump_file, " stmt_a: "); |
4212 | print_gimple_stmt (dump_file, DR_STMT (dra), 0, TDF_SLIM); | |
4213 | fprintf (dump_file, " stmt_b: "); | |
4214 | print_gimple_stmt (dump_file, DR_STMT (drb), 0, TDF_SLIM); | |
2146e26d | 4215 | } |
6b421feb | 4216 | |
2146e26d | 4217 | /* Analyze only when the dependence relation is not yet known. */ |
c76b51be | 4218 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
2146e26d | 4219 | { |
6b421feb | 4220 | dependence_stats.num_dependence_tests++; |
4221 | ||
8c7b1d8e | 4222 | if (access_functions_are_affine_or_constant_p (dra, loop_nest) |
4223 | && access_functions_are_affine_or_constant_p (drb, loop_nest)) | |
355572cc | 4224 | { |
984cebc1 | 4225 | subscript_dependence_tester (ddr, loop_nest); |
4226 | ||
355572cc | 4227 | if (flag_check_data_deps) |
4228 | { | |
984cebc1 | 4229 | /* Dump the dependences from the first algorithm. */ |
355572cc | 4230 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4231 | { | |
4232 | fprintf (dump_file, "\n\nBanerjee Analyzer\n"); | |
4233 | dump_data_dependence_relation (dump_file, ddr); | |
4234 | } | |
4235 | ||
4236 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
4237 | { | |
4238 | bool maybe_dependent; | |
f1f41a6c | 4239 | vec<lambda_vector> dir_vects, dist_vects; |
355572cc | 4240 | |
4241 | /* Save the result of the first DD analyzer. */ | |
4242 | dist_vects = DDR_DIST_VECTS (ddr); | |
4243 | dir_vects = DDR_DIR_VECTS (ddr); | |
4244 | ||
4245 | /* Reset the information. */ | |
f1f41a6c | 4246 | DDR_DIST_VECTS (ddr).create (0); |
4247 | DDR_DIR_VECTS (ddr).create (0); | |
355572cc | 4248 | |
4249 | /* Compute the same information using Omega. */ | |
4250 | if (!init_omega_for_ddr (ddr, &maybe_dependent)) | |
4251 | goto csys_dont_know; | |
4252 | ||
4253 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4254 | { | |
4255 | fprintf (dump_file, "Omega Analyzer\n"); | |
4256 | dump_data_dependence_relation (dump_file, ddr); | |
4257 | } | |
4258 | ||
4259 | /* Check that we get the same information. */ | |
4260 | if (maybe_dependent) | |
4261 | gcc_assert (ddr_consistent_p (stderr, ddr, dist_vects, | |
4262 | dir_vects)); | |
4263 | } | |
4264 | } | |
355572cc | 4265 | } |
48e1416a | 4266 | |
2146e26d | 4267 | /* As a last case, if the dependence cannot be determined, or if |
4268 | the dependence is considered too difficult to determine, answer | |
4269 | "don't know". */ | |
4270 | else | |
6b421feb | 4271 | { |
355572cc | 4272 | csys_dont_know:; |
6b421feb | 4273 | dependence_stats.num_dependence_undetermined++; |
4274 | ||
4275 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4276 | { | |
4277 | fprintf (dump_file, "Data ref a:\n"); | |
4278 | dump_data_reference (dump_file, dra); | |
4279 | fprintf (dump_file, "Data ref b:\n"); | |
4280 | dump_data_reference (dump_file, drb); | |
4281 | fprintf (dump_file, "affine dependence test not usable: access function not affine or constant.\n"); | |
4282 | } | |
4283 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
4284 | } | |
2146e26d | 4285 | } |
48e1416a | 4286 | |
2146e26d | 4287 | if (dump_file && (dump_flags & TDF_DETAILS)) |
95539e1d | 4288 | { |
4289 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) | |
4290 | fprintf (dump_file, ") -> no dependence\n"); | |
4291 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) | |
4292 | fprintf (dump_file, ") -> dependence analysis failed\n"); | |
4293 | else | |
4294 | fprintf (dump_file, ")\n"); | |
4295 | } | |
2146e26d | 4296 | } |
4297 | ||
b44d1046 | 4298 | /* Compute in DEPENDENCE_RELATIONS the data dependence graph for all |
4299 | the data references in DATAREFS, in the LOOP_NEST. When | |
41c7a324 | 4300 | COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self |
c7af8ae7 | 4301 | relations. Return true when successful, i.e. data references number |
4302 | is small enough to be handled. */ | |
2146e26d | 4303 | |
c7af8ae7 | 4304 | bool |
f1f41a6c | 4305 | compute_all_dependences (vec<data_reference_p> datarefs, |
4306 | vec<ddr_p> *dependence_relations, | |
4307 | vec<loop_p> loop_nest, | |
41c7a324 | 4308 | bool compute_self_and_rr) |
2146e26d | 4309 | { |
41c7a324 | 4310 | struct data_dependence_relation *ddr; |
4311 | struct data_reference *a, *b; | |
4312 | unsigned int i, j; | |
2146e26d | 4313 | |
f1f41a6c | 4314 | if ((int) datarefs.length () |
c7af8ae7 | 4315 | > PARAM_VALUE (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS)) |
4316 | { | |
4317 | struct data_dependence_relation *ddr; | |
4318 | ||
4319 | /* Insert a single relation into dependence_relations: | |
4320 | chrec_dont_know. */ | |
4321 | ddr = initialize_data_dependence_relation (NULL, NULL, loop_nest); | |
f1f41a6c | 4322 | dependence_relations->safe_push (ddr); |
c7af8ae7 | 4323 | return false; |
4324 | } | |
4325 | ||
f1f41a6c | 4326 | FOR_EACH_VEC_ELT (datarefs, i, a) |
4327 | for (j = i + 1; datarefs.iterate (j, &b); j++) | |
9ff25603 | 4328 | if (DR_IS_WRITE (a) || DR_IS_WRITE (b) || compute_self_and_rr) |
41c7a324 | 4329 | { |
4330 | ddr = initialize_data_dependence_relation (a, b, loop_nest); | |
f1f41a6c | 4331 | dependence_relations->safe_push (ddr); |
4332 | if (loop_nest.exists ()) | |
4333 | compute_affine_dependence (ddr, loop_nest[0]); | |
41c7a324 | 4334 | } |
02d46b9c | 4335 | |
41c7a324 | 4336 | if (compute_self_and_rr) |
f1f41a6c | 4337 | FOR_EACH_VEC_ELT (datarefs, i, a) |
2146e26d | 4338 | { |
41c7a324 | 4339 | ddr = initialize_data_dependence_relation (a, a, loop_nest); |
f1f41a6c | 4340 | dependence_relations->safe_push (ddr); |
4341 | if (loop_nest.exists ()) | |
4342 | compute_affine_dependence (ddr, loop_nest[0]); | |
2146e26d | 4343 | } |
c7af8ae7 | 4344 | |
4345 | return true; | |
2146e26d | 4346 | } |
4347 | ||
d129ada0 | 4348 | /* Describes a location of a memory reference. */ |
4349 | ||
4350 | typedef struct data_ref_loc_d | |
4351 | { | |
239dd34a | 4352 | /* The memory reference. */ |
4353 | tree ref; | |
d129ada0 | 4354 | |
07e3bcbf | 4355 | /* True if the memory reference is read. */ |
4356 | bool is_read; | |
d129ada0 | 4357 | } data_ref_loc; |
4358 | ||
d129ada0 | 4359 | |
faa56cf9 | 4360 | /* Stores the locations of memory references in STMT to REFERENCES. Returns |
4361 | true if STMT clobbers memory, false otherwise. */ | |
4362 | ||
d129ada0 | 4363 | static bool |
d70aebca | 4364 | get_references_in_stmt (gimple stmt, vec<data_ref_loc, va_heap> *references) |
faa56cf9 | 4365 | { |
4366 | bool clobbers_memory = false; | |
e82e4eb5 | 4367 | data_ref_loc ref; |
239dd34a | 4368 | tree op0, op1; |
75a70cf9 | 4369 | enum gimple_code stmt_code = gimple_code (stmt); |
faa56cf9 | 4370 | |
faa56cf9 | 4371 | /* ASM_EXPR and CALL_EXPR may embed arbitrary side effects. |
0ef2a6d1 | 4372 | As we cannot model data-references to not spelled out |
4373 | accesses give up if they may occur. */ | |
3d483a94 | 4374 | if (stmt_code == GIMPLE_CALL |
4375 | && !(gimple_call_flags (stmt) & ECF_CONST)) | |
4376 | { | |
4377 | /* Allow IFN_GOMP_SIMD_LANE in their own loops. */ | |
c71d3c24 | 4378 | if (gimple_call_internal_p (stmt)) |
4379 | switch (gimple_call_internal_fn (stmt)) | |
4380 | { | |
4381 | case IFN_GOMP_SIMD_LANE: | |
4382 | { | |
4383 | struct loop *loop = gimple_bb (stmt)->loop_father; | |
4384 | tree uid = gimple_call_arg (stmt, 0); | |
4385 | gcc_assert (TREE_CODE (uid) == SSA_NAME); | |
4386 | if (loop == NULL | |
4387 | || loop->simduid != SSA_NAME_VAR (uid)) | |
4388 | clobbers_memory = true; | |
4389 | break; | |
4390 | } | |
4391 | case IFN_MASK_LOAD: | |
4392 | case IFN_MASK_STORE: | |
4393 | break; | |
4394 | default: | |
3d483a94 | 4395 | clobbers_memory = true; |
c71d3c24 | 4396 | break; |
4397 | } | |
3d483a94 | 4398 | else |
4399 | clobbers_memory = true; | |
4400 | } | |
4401 | else if (stmt_code == GIMPLE_ASM | |
4402 | && (gimple_asm_volatile_p (stmt) || gimple_vuse (stmt))) | |
faa56cf9 | 4403 | clobbers_memory = true; |
4404 | ||
dd277d48 | 4405 | if (!gimple_vuse (stmt)) |
faa56cf9 | 4406 | return clobbers_memory; |
4407 | ||
75a70cf9 | 4408 | if (stmt_code == GIMPLE_ASSIGN) |
faa56cf9 | 4409 | { |
ffb04365 | 4410 | tree base; |
239dd34a | 4411 | op0 = gimple_assign_lhs (stmt); |
4412 | op1 = gimple_assign_rhs1 (stmt); | |
48e1416a | 4413 | |
239dd34a | 4414 | if (DECL_P (op1) |
4415 | || (REFERENCE_CLASS_P (op1) | |
4416 | && (base = get_base_address (op1)) | |
ffb04365 | 4417 | && TREE_CODE (base) != SSA_NAME)) |
faa56cf9 | 4418 | { |
239dd34a | 4419 | ref.ref = op1; |
e82e4eb5 | 4420 | ref.is_read = true; |
f1f41a6c | 4421 | references->safe_push (ref); |
faa56cf9 | 4422 | } |
faa56cf9 | 4423 | } |
75a70cf9 | 4424 | else if (stmt_code == GIMPLE_CALL) |
faa56cf9 | 4425 | { |
9f2e27ae | 4426 | unsigned i, n; |
d97e22fb | 4427 | |
c71d3c24 | 4428 | ref.is_read = false; |
4429 | if (gimple_call_internal_p (stmt)) | |
4430 | switch (gimple_call_internal_fn (stmt)) | |
4431 | { | |
4432 | case IFN_MASK_LOAD: | |
4e459157 | 4433 | if (gimple_call_lhs (stmt) == NULL_TREE) |
4434 | break; | |
c71d3c24 | 4435 | ref.is_read = true; |
4436 | case IFN_MASK_STORE: | |
4437 | ref.ref = fold_build2 (MEM_REF, | |
4438 | ref.is_read | |
4439 | ? TREE_TYPE (gimple_call_lhs (stmt)) | |
4440 | : TREE_TYPE (gimple_call_arg (stmt, 3)), | |
4441 | gimple_call_arg (stmt, 0), | |
4442 | gimple_call_arg (stmt, 1)); | |
4443 | references->safe_push (ref); | |
4444 | return false; | |
4445 | default: | |
4446 | break; | |
4447 | } | |
4448 | ||
239dd34a | 4449 | op0 = gimple_call_lhs (stmt); |
9f2e27ae | 4450 | n = gimple_call_num_args (stmt); |
d97e22fb | 4451 | for (i = 0; i < n; i++) |
faa56cf9 | 4452 | { |
239dd34a | 4453 | op1 = gimple_call_arg (stmt, i); |
d97e22fb | 4454 | |
239dd34a | 4455 | if (DECL_P (op1) |
4456 | || (REFERENCE_CLASS_P (op1) && get_base_address (op1))) | |
faa56cf9 | 4457 | { |
239dd34a | 4458 | ref.ref = op1; |
e82e4eb5 | 4459 | ref.is_read = true; |
f1f41a6c | 4460 | references->safe_push (ref); |
faa56cf9 | 4461 | } |
4462 | } | |
4463 | } | |
9f2e27ae | 4464 | else |
4465 | return clobbers_memory; | |
faa56cf9 | 4466 | |
239dd34a | 4467 | if (op0 |
4468 | && (DECL_P (op0) | |
4469 | || (REFERENCE_CLASS_P (op0) && get_base_address (op0)))) | |
9f2e27ae | 4470 | { |
239dd34a | 4471 | ref.ref = op0; |
e82e4eb5 | 4472 | ref.is_read = false; |
f1f41a6c | 4473 | references->safe_push (ref); |
9f2e27ae | 4474 | } |
faa56cf9 | 4475 | return clobbers_memory; |
4476 | } | |
4477 | ||
4478 | /* Stores the data references in STMT to DATAREFS. If there is an unanalyzable | |
80bb306a | 4479 | reference, returns false, otherwise returns true. NEST is the outermost |
255b6be7 | 4480 | loop of the loop nest in which the references should be analyzed. */ |
faa56cf9 | 4481 | |
255b6be7 | 4482 | bool |
75a70cf9 | 4483 | find_data_references_in_stmt (struct loop *nest, gimple stmt, |
f1f41a6c | 4484 | vec<data_reference_p> *datarefs) |
faa56cf9 | 4485 | { |
4486 | unsigned i; | |
4997014d | 4487 | auto_vec<data_ref_loc, 2> references; |
faa56cf9 | 4488 | data_ref_loc *ref; |
4489 | bool ret = true; | |
4490 | data_reference_p dr; | |
4491 | ||
4492 | if (get_references_in_stmt (stmt, &references)) | |
d70aebca | 4493 | return false; |
faa56cf9 | 4494 | |
f1f41a6c | 4495 | FOR_EACH_VEC_ELT (references, i, ref) |
faa56cf9 | 4496 | { |
221a697e | 4497 | dr = create_data_ref (nest, loop_containing_stmt (stmt), |
239dd34a | 4498 | ref->ref, stmt, ref->is_read); |
ad4a85ad | 4499 | gcc_assert (dr != NULL); |
f1f41a6c | 4500 | datarefs->safe_push (dr); |
faa56cf9 | 4501 | } |
f1f41a6c | 4502 | references.release (); |
faa56cf9 | 4503 | return ret; |
4504 | } | |
4505 | ||
221a697e | 4506 | /* Stores the data references in STMT to DATAREFS. If there is an |
4507 | unanalyzable reference, returns false, otherwise returns true. | |
4508 | NEST is the outermost loop of the loop nest in which the references | |
4509 | should be instantiated, LOOP is the loop in which the references | |
4510 | should be analyzed. */ | |
c794d738 | 4511 | |
4512 | bool | |
221a697e | 4513 | graphite_find_data_references_in_stmt (loop_p nest, loop_p loop, gimple stmt, |
f1f41a6c | 4514 | vec<data_reference_p> *datarefs) |
c794d738 | 4515 | { |
4516 | unsigned i; | |
4997014d | 4517 | auto_vec<data_ref_loc, 2> references; |
c794d738 | 4518 | data_ref_loc *ref; |
4519 | bool ret = true; | |
4520 | data_reference_p dr; | |
4521 | ||
4522 | if (get_references_in_stmt (stmt, &references)) | |
d70aebca | 4523 | return false; |
c794d738 | 4524 | |
f1f41a6c | 4525 | FOR_EACH_VEC_ELT (references, i, ref) |
c794d738 | 4526 | { |
239dd34a | 4527 | dr = create_data_ref (nest, loop, ref->ref, stmt, ref->is_read); |
c794d738 | 4528 | gcc_assert (dr != NULL); |
f1f41a6c | 4529 | datarefs->safe_push (dr); |
c794d738 | 4530 | } |
4531 | ||
f1f41a6c | 4532 | references.release (); |
c794d738 | 4533 | return ret; |
4534 | } | |
4535 | ||
37545e54 | 4536 | /* Search the data references in LOOP, and record the information into |
4537 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4538 | difficult case, returns NULL_TREE otherwise. */ | |
4539 | ||
ec611e12 | 4540 | tree |
37545e54 | 4541 | find_data_references_in_bb (struct loop *loop, basic_block bb, |
f1f41a6c | 4542 | vec<data_reference_p> *datarefs) |
37545e54 | 4543 | { |
4544 | gimple_stmt_iterator bsi; | |
4545 | ||
4546 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
4547 | { | |
4548 | gimple stmt = gsi_stmt (bsi); | |
4549 | ||
4550 | if (!find_data_references_in_stmt (loop, stmt, datarefs)) | |
4551 | { | |
4552 | struct data_reference *res; | |
4553 | res = XCNEW (struct data_reference); | |
f1f41a6c | 4554 | datarefs->safe_push (res); |
37545e54 | 4555 | |
4556 | return chrec_dont_know; | |
4557 | } | |
4558 | } | |
4559 | ||
4560 | return NULL_TREE; | |
4561 | } | |
4562 | ||
2146e26d | 4563 | /* Search the data references in LOOP, and record the information into |
4564 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4565 | difficult case, returns NULL_TREE otherwise. | |
80bb306a | 4566 | |
557ef5d8 | 4567 | TODO: This function should be made smarter so that it can handle address |
4568 | arithmetic as if they were array accesses, etc. */ | |
2146e26d | 4569 | |
07e3bcbf | 4570 | tree |
41c7a324 | 4571 | find_data_references_in_loop (struct loop *loop, |
f1f41a6c | 4572 | vec<data_reference_p> *datarefs) |
2146e26d | 4573 | { |
0332ea54 | 4574 | basic_block bb, *bbs; |
4575 | unsigned int i; | |
bc3c8ad4 | 4576 | |
ad4a85ad | 4577 | bbs = get_loop_body_in_dom_order (loop); |
0332ea54 | 4578 | |
4579 | for (i = 0; i < loop->num_nodes; i++) | |
2146e26d | 4580 | { |
0332ea54 | 4581 | bb = bbs[i]; |
4582 | ||
37545e54 | 4583 | if (find_data_references_in_bb (loop, bb, datarefs) == chrec_dont_know) |
4584 | { | |
4585 | free (bbs); | |
4586 | return chrec_dont_know; | |
4587 | } | |
2146e26d | 4588 | } |
0332ea54 | 4589 | free (bbs); |
4590 | ||
4a012ac6 | 4591 | return NULL_TREE; |
2146e26d | 4592 | } |
4593 | ||
b44d1046 | 4594 | /* Recursive helper function. */ |
4595 | ||
4596 | static bool | |
f1f41a6c | 4597 | find_loop_nest_1 (struct loop *loop, vec<loop_p> *loop_nest) |
b44d1046 | 4598 | { |
4599 | /* Inner loops of the nest should not contain siblings. Example: | |
4600 | when there are two consecutive loops, | |
4601 | ||
4602 | | loop_0 | |
4603 | | loop_1 | |
4604 | | A[{0, +, 1}_1] | |
4605 | | endloop_1 | |
4606 | | loop_2 | |
4607 | | A[{0, +, 1}_2] | |
4608 | | endloop_2 | |
4609 | | endloop_0 | |
4610 | ||
4611 | the dependence relation cannot be captured by the distance | |
4612 | abstraction. */ | |
4613 | if (loop->next) | |
4614 | return false; | |
2146e26d | 4615 | |
f1f41a6c | 4616 | loop_nest->safe_push (loop); |
b44d1046 | 4617 | if (loop->inner) |
4618 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4619 | return true; | |
4620 | } | |
4621 | ||
4622 | /* Return false when the LOOP is not well nested. Otherwise return | |
4623 | true and insert in LOOP_NEST the loops of the nest. LOOP_NEST will | |
4624 | contain the loops from the outermost to the innermost, as they will | |
4625 | appear in the classic distance vector. */ | |
4626 | ||
5c205353 | 4627 | bool |
f1f41a6c | 4628 | find_loop_nest (struct loop *loop, vec<loop_p> *loop_nest) |
b44d1046 | 4629 | { |
f1f41a6c | 4630 | loop_nest->safe_push (loop); |
b44d1046 | 4631 | if (loop->inner) |
4632 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4633 | return true; | |
4634 | } | |
2146e26d | 4635 | |
b79b3386 | 4636 | /* Returns true when the data dependences have been computed, false otherwise. |
4637 | Given a loop nest LOOP, the following vectors are returned: | |
48e1416a | 4638 | DATAREFS is initialized to all the array elements contained in this loop, |
4639 | DEPENDENCE_RELATIONS contains the relations between the data references. | |
4640 | Compute read-read and self relations if | |
516849c7 | 4641 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ |
2146e26d | 4642 | |
b79b3386 | 4643 | bool |
48e1416a | 4644 | compute_data_dependences_for_loop (struct loop *loop, |
516849c7 | 4645 | bool compute_self_and_read_read_dependences, |
f1f41a6c | 4646 | vec<loop_p> *loop_nest, |
4647 | vec<data_reference_p> *datarefs, | |
4648 | vec<ddr_p> *dependence_relations) | |
2146e26d | 4649 | { |
b79b3386 | 4650 | bool res = true; |
516849c7 | 4651 | |
6b421feb | 4652 | memset (&dependence_stats, 0, sizeof (dependence_stats)); |
2146e26d | 4653 | |
48e1416a | 4654 | /* If the loop nest is not well formed, or one of the data references |
b44d1046 | 4655 | is not computable, give up without spending time to compute other |
4656 | dependences. */ | |
80bb306a | 4657 | if (!loop |
a8af2e86 | 4658 | || !find_loop_nest (loop, loop_nest) |
c7af8ae7 | 4659 | || find_data_references_in_loop (loop, datarefs) == chrec_dont_know |
4660 | || !compute_all_dependences (*datarefs, dependence_relations, *loop_nest, | |
4661 | compute_self_and_read_read_dependences)) | |
4662 | res = false; | |
6b421feb | 4663 | |
4664 | if (dump_file && (dump_flags & TDF_STATS)) | |
2146e26d | 4665 | { |
6b421feb | 4666 | fprintf (dump_file, "Dependence tester statistics:\n"); |
4667 | ||
48e1416a | 4668 | fprintf (dump_file, "Number of dependence tests: %d\n", |
6b421feb | 4669 | dependence_stats.num_dependence_tests); |
48e1416a | 4670 | fprintf (dump_file, "Number of dependence tests classified dependent: %d\n", |
6b421feb | 4671 | dependence_stats.num_dependence_dependent); |
48e1416a | 4672 | fprintf (dump_file, "Number of dependence tests classified independent: %d\n", |
6b421feb | 4673 | dependence_stats.num_dependence_independent); |
48e1416a | 4674 | fprintf (dump_file, "Number of undetermined dependence tests: %d\n", |
6b421feb | 4675 | dependence_stats.num_dependence_undetermined); |
4676 | ||
48e1416a | 4677 | fprintf (dump_file, "Number of subscript tests: %d\n", |
6b421feb | 4678 | dependence_stats.num_subscript_tests); |
48e1416a | 4679 | fprintf (dump_file, "Number of undetermined subscript tests: %d\n", |
6b421feb | 4680 | dependence_stats.num_subscript_undetermined); |
48e1416a | 4681 | fprintf (dump_file, "Number of same subscript function: %d\n", |
6b421feb | 4682 | dependence_stats.num_same_subscript_function); |
4683 | ||
4684 | fprintf (dump_file, "Number of ziv tests: %d\n", | |
4685 | dependence_stats.num_ziv); | |
4686 | fprintf (dump_file, "Number of ziv tests returning dependent: %d\n", | |
4687 | dependence_stats.num_ziv_dependent); | |
4688 | fprintf (dump_file, "Number of ziv tests returning independent: %d\n", | |
4689 | dependence_stats.num_ziv_independent); | |
4690 | fprintf (dump_file, "Number of ziv tests unimplemented: %d\n", | |
48e1416a | 4691 | dependence_stats.num_ziv_unimplemented); |
6b421feb | 4692 | |
48e1416a | 4693 | fprintf (dump_file, "Number of siv tests: %d\n", |
6b421feb | 4694 | dependence_stats.num_siv); |
4695 | fprintf (dump_file, "Number of siv tests returning dependent: %d\n", | |
4696 | dependence_stats.num_siv_dependent); | |
4697 | fprintf (dump_file, "Number of siv tests returning independent: %d\n", | |
4698 | dependence_stats.num_siv_independent); | |
4699 | fprintf (dump_file, "Number of siv tests unimplemented: %d\n", | |
4700 | dependence_stats.num_siv_unimplemented); | |
4701 | ||
48e1416a | 4702 | fprintf (dump_file, "Number of miv tests: %d\n", |
6b421feb | 4703 | dependence_stats.num_miv); |
4704 | fprintf (dump_file, "Number of miv tests returning dependent: %d\n", | |
4705 | dependence_stats.num_miv_dependent); | |
4706 | fprintf (dump_file, "Number of miv tests returning independent: %d\n", | |
4707 | dependence_stats.num_miv_independent); | |
4708 | fprintf (dump_file, "Number of miv tests unimplemented: %d\n", | |
4709 | dependence_stats.num_miv_unimplemented); | |
b79b3386 | 4710 | } |
4711 | ||
4712 | return res; | |
2146e26d | 4713 | } |
4714 | ||
48e1416a | 4715 | /* Returns true when the data dependences for the basic block BB have been |
37545e54 | 4716 | computed, false otherwise. |
48e1416a | 4717 | DATAREFS is initialized to all the array elements contained in this basic |
37545e54 | 4718 | block, DEPENDENCE_RELATIONS contains the relations between the data |
4719 | references. Compute read-read and self relations if | |
4720 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ | |
4721 | bool | |
4722 | compute_data_dependences_for_bb (basic_block bb, | |
4723 | bool compute_self_and_read_read_dependences, | |
f1f41a6c | 4724 | vec<data_reference_p> *datarefs, |
4725 | vec<ddr_p> *dependence_relations) | |
37545e54 | 4726 | { |
4727 | if (find_data_references_in_bb (NULL, bb, datarefs) == chrec_dont_know) | |
4728 | return false; | |
4729 | ||
1e094109 | 4730 | return compute_all_dependences (*datarefs, dependence_relations, vNULL, |
c7af8ae7 | 4731 | compute_self_and_read_read_dependences); |
37545e54 | 4732 | } |
4733 | ||
2146e26d | 4734 | /* Entry point (for testing only). Analyze all the data references |
355572cc | 4735 | and the dependence relations in LOOP. |
2146e26d | 4736 | |
48e1416a | 4737 | The data references are computed first. |
4738 | ||
2146e26d | 4739 | A relation on these nodes is represented by a complete graph. Some |
4740 | of the relations could be of no interest, thus the relations can be | |
4741 | computed on demand. | |
48e1416a | 4742 | |
2146e26d | 4743 | In the following function we compute all the relations. This is |
4744 | just a first implementation that is here for: | |
48e1416a | 4745 | - for showing how to ask for the dependence relations, |
2146e26d | 4746 | - for the debugging the whole dependence graph, |
4747 | - for the dejagnu testcases and maintenance. | |
48e1416a | 4748 | |
2146e26d | 4749 | It is possible to ask only for a part of the graph, avoiding to |
4750 | compute the whole dependence graph. The computed dependences are | |
4751 | stored in a knowledge base (KB) such that later queries don't | |
4752 | recompute the same information. The implementation of this KB is | |
4753 | transparent to the optimizer, and thus the KB can be changed with a | |
4754 | more efficient implementation, or the KB could be disabled. */ | |
48e1416a | 4755 | static void |
355572cc | 4756 | analyze_all_data_dependences (struct loop *loop) |
2146e26d | 4757 | { |
4758 | unsigned int i; | |
2146e26d | 4759 | int nb_data_refs = 10; |
f1f41a6c | 4760 | vec<data_reference_p> datarefs; |
4761 | datarefs.create (nb_data_refs); | |
4762 | vec<ddr_p> dependence_relations; | |
4763 | dependence_relations.create (nb_data_refs * nb_data_refs); | |
4764 | vec<loop_p> loop_nest; | |
4765 | loop_nest.create (3); | |
2146e26d | 4766 | |
4767 | /* Compute DDs on the whole function. */ | |
a8af2e86 | 4768 | compute_data_dependences_for_loop (loop, false, &loop_nest, &datarefs, |
355572cc | 4769 | &dependence_relations); |
2146e26d | 4770 | |
4771 | if (dump_file) | |
4772 | { | |
4773 | dump_data_dependence_relations (dump_file, dependence_relations); | |
4774 | fprintf (dump_file, "\n\n"); | |
2146e26d | 4775 | |
bc3c8ad4 | 4776 | if (dump_flags & TDF_DETAILS) |
4777 | dump_dist_dir_vectors (dump_file, dependence_relations); | |
2146e26d | 4778 | |
bc3c8ad4 | 4779 | if (dump_flags & TDF_STATS) |
2146e26d | 4780 | { |
bc3c8ad4 | 4781 | unsigned nb_top_relations = 0; |
4782 | unsigned nb_bot_relations = 0; | |
bc3c8ad4 | 4783 | unsigned nb_chrec_relations = 0; |
41c7a324 | 4784 | struct data_dependence_relation *ddr; |
bc3c8ad4 | 4785 | |
f1f41a6c | 4786 | FOR_EACH_VEC_ELT (dependence_relations, i, ddr) |
bc3c8ad4 | 4787 | { |
bc3c8ad4 | 4788 | if (chrec_contains_undetermined (DDR_ARE_DEPENDENT (ddr))) |
4789 | nb_top_relations++; | |
48e1416a | 4790 | |
bc3c8ad4 | 4791 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
dd277d48 | 4792 | nb_bot_relations++; |
48e1416a | 4793 | |
4794 | else | |
bc3c8ad4 | 4795 | nb_chrec_relations++; |
4796 | } | |
48e1416a | 4797 | |
bc3c8ad4 | 4798 | gather_stats_on_scev_database (); |
4799 | } | |
2146e26d | 4800 | } |
6b6f234c | 4801 | |
f1f41a6c | 4802 | loop_nest.release (); |
6b6f234c | 4803 | free_dependence_relations (dependence_relations); |
4804 | free_data_refs (datarefs); | |
4805 | } | |
355572cc | 4806 | |
4807 | /* Computes all the data dependences and check that the results of | |
4808 | several analyzers are the same. */ | |
4809 | ||
4810 | void | |
4811 | tree_check_data_deps (void) | |
4812 | { | |
355572cc | 4813 | struct loop *loop_nest; |
4814 | ||
f21d4d00 | 4815 | FOR_EACH_LOOP (loop_nest, 0) |
355572cc | 4816 | analyze_all_data_dependences (loop_nest); |
4817 | } | |
6b6f234c | 4818 | |
4819 | /* Free the memory used by a data dependence relation DDR. */ | |
4820 | ||
4821 | void | |
4822 | free_dependence_relation (struct data_dependence_relation *ddr) | |
4823 | { | |
4824 | if (ddr == NULL) | |
4825 | return; | |
4826 | ||
f1f41a6c | 4827 | if (DDR_SUBSCRIPTS (ddr).exists ()) |
87da4f2e | 4828 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
f1f41a6c | 4829 | DDR_DIST_VECTS (ddr).release (); |
4830 | DDR_DIR_VECTS (ddr).release (); | |
41c7a324 | 4831 | |
6b6f234c | 4832 | free (ddr); |
4833 | } | |
4834 | ||
4835 | /* Free the memory used by the data dependence relations from | |
4836 | DEPENDENCE_RELATIONS. */ | |
4837 | ||
48e1416a | 4838 | void |
f1f41a6c | 4839 | free_dependence_relations (vec<ddr_p> dependence_relations) |
6b6f234c | 4840 | { |
4841 | unsigned int i; | |
41c7a324 | 4842 | struct data_dependence_relation *ddr; |
6b6f234c | 4843 | |
f1f41a6c | 4844 | FOR_EACH_VEC_ELT (dependence_relations, i, ddr) |
a8af2e86 | 4845 | if (ddr) |
62761183 | 4846 | free_dependence_relation (ddr); |
41c7a324 | 4847 | |
f1f41a6c | 4848 | dependence_relations.release (); |
2146e26d | 4849 | } |
4850 | ||
6b6f234c | 4851 | /* Free the memory used by the data references from DATAREFS. */ |
4852 | ||
4853 | void | |
f1f41a6c | 4854 | free_data_refs (vec<data_reference_p> datarefs) |
6b6f234c | 4855 | { |
4856 | unsigned int i; | |
41c7a324 | 4857 | struct data_reference *dr; |
2146e26d | 4858 | |
f1f41a6c | 4859 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
31e389a2 | 4860 | free_data_ref (dr); |
f1f41a6c | 4861 | datarefs.release (); |
6b6f234c | 4862 | } |