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56cf8686 | 1 | /* Data references and dependences detectors. |
66647d44 JJ |
2 | Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 |
3 | Free Software Foundation, Inc. | |
0ff4040e | 4 | Contributed by Sebastian Pop <pop@cri.ensmp.fr> |
56cf8686 SP |
5 | |
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 10 | Software Foundation; either version 3, or (at your option) any later |
56cf8686 SP |
11 | version. |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
56cf8686 SP |
21 | |
22 | /* This pass walks a given loop structure searching for array | |
23 | references. The information about the array accesses is recorded | |
24 | in DATA_REFERENCE structures. | |
25 | ||
26 | The basic test for determining the dependences is: | |
27 | given two access functions chrec1 and chrec2 to a same array, and | |
28 | x and y two vectors from the iteration domain, the same element of | |
29 | the array is accessed twice at iterations x and y if and only if: | |
30 | | chrec1 (x) == chrec2 (y). | |
31 | ||
32 | The goals of this analysis are: | |
33 | ||
34 | - to determine the independence: the relation between two | |
35 | independent accesses is qualified with the chrec_known (this | |
36 | information allows a loop parallelization), | |
37 | ||
38 | - when two data references access the same data, to qualify the | |
39 | dependence relation with classic dependence representations: | |
40 | ||
41 | - distance vectors | |
42 | - direction vectors | |
43 | - loop carried level dependence | |
44 | - polyhedron dependence | |
45 | or with the chains of recurrences based representation, | |
46 | ||
50300b4c | 47 | - to define a knowledge base for storing the data dependence |
56cf8686 SP |
48 | information, |
49 | ||
50 | - to define an interface to access this data. | |
51 | ||
52 | ||
53 | Definitions: | |
54 | ||
55 | - subscript: given two array accesses a subscript is the tuple | |
56 | composed of the access functions for a given dimension. Example: | |
57 | Given A[f1][f2][f3] and B[g1][g2][g3], there are three subscripts: | |
58 | (f1, g1), (f2, g2), (f3, g3). | |
59 | ||
60 | - Diophantine equation: an equation whose coefficients and | |
61 | solutions are integer constants, for example the equation | |
62 | | 3*x + 2*y = 1 | |
63 | has an integer solution x = 1 and y = -1. | |
64 | ||
65 | References: | |
66 | ||
67 | - "Advanced Compilation for High Performance Computing" by Randy | |
68 | Allen and Ken Kennedy. | |
69 | http://citeseer.ist.psu.edu/goff91practical.html | |
70 | ||
71 | - "Loop Transformations for Restructuring Compilers - The Foundations" | |
72 | by Utpal Banerjee. | |
73 | ||
74 | ||
75 | */ | |
76 | ||
77 | #include "config.h" | |
78 | #include "system.h" | |
79 | #include "coretypes.h" | |
80 | #include "tm.h" | |
56cf8686 SP |
81 | #include "ggc.h" |
82 | #include "tree.h" | |
83 | ||
84 | /* These RTL headers are needed for basic-block.h. */ | |
85 | #include "rtl.h" | |
86 | #include "basic-block.h" | |
87 | #include "diagnostic.h" | |
88 | #include "tree-flow.h" | |
89 | #include "tree-dump.h" | |
90 | #include "timevar.h" | |
91 | #include "cfgloop.h" | |
56cf8686 SP |
92 | #include "tree-data-ref.h" |
93 | #include "tree-scalar-evolution.h" | |
94 | #include "tree-pass.h" | |
946e1bc7 | 95 | #include "langhooks.h" |
56cf8686 | 96 | |
0ff4040e SP |
97 | static struct datadep_stats |
98 | { | |
99 | int num_dependence_tests; | |
100 | int num_dependence_dependent; | |
101 | int num_dependence_independent; | |
102 | int num_dependence_undetermined; | |
103 | ||
104 | int num_subscript_tests; | |
105 | int num_subscript_undetermined; | |
106 | int num_same_subscript_function; | |
107 | ||
108 | int num_ziv; | |
109 | int num_ziv_independent; | |
110 | int num_ziv_dependent; | |
111 | int num_ziv_unimplemented; | |
112 | ||
113 | int num_siv; | |
114 | int num_siv_independent; | |
115 | int num_siv_dependent; | |
116 | int num_siv_unimplemented; | |
117 | ||
118 | int num_miv; | |
119 | int num_miv_independent; | |
120 | int num_miv_dependent; | |
121 | int num_miv_unimplemented; | |
122 | } dependence_stats; | |
123 | ||
ba42e045 SP |
124 | static bool subscript_dependence_tester_1 (struct data_dependence_relation *, |
125 | struct data_reference *, | |
da9a21f4 SP |
126 | struct data_reference *, |
127 | struct loop *); | |
56cf8686 SP |
128 | /* Returns true iff A divides B. */ |
129 | ||
130 | static inline bool | |
ed7a4b4b | 131 | tree_fold_divides_p (const_tree a, const_tree b) |
56cf8686 | 132 | { |
b73a6056 RS |
133 | gcc_assert (TREE_CODE (a) == INTEGER_CST); |
134 | gcc_assert (TREE_CODE (b) == INTEGER_CST); | |
135 | return integer_zerop (int_const_binop (TRUNC_MOD_EXPR, b, a, 0)); | |
56cf8686 SP |
136 | } |
137 | ||
86df10e3 SP |
138 | /* Returns true iff A divides B. */ |
139 | ||
140 | static inline bool | |
141 | int_divides_p (int a, int b) | |
142 | { | |
143 | return ((b % a) == 0); | |
56cf8686 SP |
144 | } |
145 | ||
146 | \f | |
147 | ||
148 | /* Dump into FILE all the data references from DATAREFS. */ | |
149 | ||
150 | void | |
ebf78a47 | 151 | dump_data_references (FILE *file, VEC (data_reference_p, heap) *datarefs) |
56cf8686 SP |
152 | { |
153 | unsigned int i; | |
ebf78a47 SP |
154 | struct data_reference *dr; |
155 | ||
156 | for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++) | |
157 | dump_data_reference (file, dr); | |
56cf8686 SP |
158 | } |
159 | ||
a37d995a SP |
160 | /* Dump into STDERR all the data references from DATAREFS. */ |
161 | ||
162 | void | |
163 | debug_data_references (VEC (data_reference_p, heap) *datarefs) | |
164 | { | |
165 | dump_data_references (stderr, datarefs); | |
166 | } | |
167 | ||
dea61d92 SP |
168 | /* Dump to STDERR all the dependence relations from DDRS. */ |
169 | ||
170 | void | |
171 | debug_data_dependence_relations (VEC (ddr_p, heap) *ddrs) | |
172 | { | |
173 | dump_data_dependence_relations (stderr, ddrs); | |
174 | } | |
175 | ||
ebf78a47 | 176 | /* Dump into FILE all the dependence relations from DDRS. */ |
56cf8686 SP |
177 | |
178 | void | |
179 | dump_data_dependence_relations (FILE *file, | |
ebf78a47 | 180 | VEC (ddr_p, heap) *ddrs) |
56cf8686 SP |
181 | { |
182 | unsigned int i; | |
ebf78a47 SP |
183 | struct data_dependence_relation *ddr; |
184 | ||
185 | for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) | |
186 | dump_data_dependence_relation (file, ddr); | |
56cf8686 SP |
187 | } |
188 | ||
a37d995a SP |
189 | /* Print to STDERR the data_reference DR. */ |
190 | ||
191 | void | |
192 | debug_data_reference (struct data_reference *dr) | |
193 | { | |
194 | dump_data_reference (stderr, dr); | |
195 | } | |
196 | ||
56cf8686 SP |
197 | /* Dump function for a DATA_REFERENCE structure. */ |
198 | ||
199 | void | |
200 | dump_data_reference (FILE *outf, | |
201 | struct data_reference *dr) | |
202 | { | |
203 | unsigned int i; | |
204 | ||
36d59cf7 | 205 | fprintf (outf, "(Data Ref: \n stmt: "); |
726a989a | 206 | print_gimple_stmt (outf, DR_STMT (dr), 0, 0); |
56cf8686 SP |
207 | fprintf (outf, " ref: "); |
208 | print_generic_stmt (outf, DR_REF (dr), 0); | |
0ff4040e | 209 | fprintf (outf, " base_object: "); |
86a07404 | 210 | print_generic_stmt (outf, DR_BASE_OBJECT (dr), 0); |
56cf8686 SP |
211 | |
212 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) | |
213 | { | |
214 | fprintf (outf, " Access function %d: ", i); | |
215 | print_generic_stmt (outf, DR_ACCESS_FN (dr, i), 0); | |
216 | } | |
217 | fprintf (outf, ")\n"); | |
218 | } | |
219 | ||
d93817c4 ZD |
220 | /* Dumps the affine function described by FN to the file OUTF. */ |
221 | ||
222 | static void | |
223 | dump_affine_function (FILE *outf, affine_fn fn) | |
224 | { | |
225 | unsigned i; | |
226 | tree coef; | |
227 | ||
228 | print_generic_expr (outf, VEC_index (tree, fn, 0), TDF_SLIM); | |
229 | for (i = 1; VEC_iterate (tree, fn, i, coef); i++) | |
230 | { | |
231 | fprintf (outf, " + "); | |
232 | print_generic_expr (outf, coef, TDF_SLIM); | |
233 | fprintf (outf, " * x_%u", i); | |
234 | } | |
235 | } | |
236 | ||
237 | /* Dumps the conflict function CF to the file OUTF. */ | |
238 | ||
239 | static void | |
240 | dump_conflict_function (FILE *outf, conflict_function *cf) | |
241 | { | |
242 | unsigned i; | |
243 | ||
244 | if (cf->n == NO_DEPENDENCE) | |
245 | fprintf (outf, "no dependence\n"); | |
246 | else if (cf->n == NOT_KNOWN) | |
247 | fprintf (outf, "not known\n"); | |
248 | else | |
249 | { | |
250 | for (i = 0; i < cf->n; i++) | |
251 | { | |
252 | fprintf (outf, "["); | |
253 | dump_affine_function (outf, cf->fns[i]); | |
254 | fprintf (outf, "]\n"); | |
255 | } | |
256 | } | |
257 | } | |
258 | ||
86df10e3 SP |
259 | /* Dump function for a SUBSCRIPT structure. */ |
260 | ||
261 | void | |
262 | dump_subscript (FILE *outf, struct subscript *subscript) | |
263 | { | |
d93817c4 | 264 | conflict_function *cf = SUB_CONFLICTS_IN_A (subscript); |
86df10e3 SP |
265 | |
266 | fprintf (outf, "\n (subscript \n"); | |
267 | fprintf (outf, " iterations_that_access_an_element_twice_in_A: "); | |
d93817c4 ZD |
268 | dump_conflict_function (outf, cf); |
269 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
270 | { |
271 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
272 | fprintf (outf, " last_conflict: "); | |
273 | print_generic_stmt (outf, last_iteration, 0); | |
274 | } | |
275 | ||
d93817c4 | 276 | cf = SUB_CONFLICTS_IN_B (subscript); |
86df10e3 | 277 | fprintf (outf, " iterations_that_access_an_element_twice_in_B: "); |
d93817c4 ZD |
278 | dump_conflict_function (outf, cf); |
279 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
280 | { |
281 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
282 | fprintf (outf, " last_conflict: "); | |
283 | print_generic_stmt (outf, last_iteration, 0); | |
284 | } | |
285 | ||
286 | fprintf (outf, " (Subscript distance: "); | |
287 | print_generic_stmt (outf, SUB_DISTANCE (subscript), 0); | |
288 | fprintf (outf, " )\n"); | |
289 | fprintf (outf, " )\n"); | |
290 | } | |
291 | ||
0ff4040e SP |
292 | /* Print the classic direction vector DIRV to OUTF. */ |
293 | ||
294 | void | |
295 | print_direction_vector (FILE *outf, | |
296 | lambda_vector dirv, | |
297 | int length) | |
298 | { | |
299 | int eq; | |
300 | ||
301 | for (eq = 0; eq < length; eq++) | |
302 | { | |
81f40b79 ILT |
303 | enum data_dependence_direction dir = ((enum data_dependence_direction) |
304 | dirv[eq]); | |
0ff4040e SP |
305 | |
306 | switch (dir) | |
307 | { | |
308 | case dir_positive: | |
309 | fprintf (outf, " +"); | |
310 | break; | |
311 | case dir_negative: | |
312 | fprintf (outf, " -"); | |
313 | break; | |
314 | case dir_equal: | |
315 | fprintf (outf, " ="); | |
316 | break; | |
317 | case dir_positive_or_equal: | |
318 | fprintf (outf, " +="); | |
319 | break; | |
320 | case dir_positive_or_negative: | |
321 | fprintf (outf, " +-"); | |
322 | break; | |
323 | case dir_negative_or_equal: | |
324 | fprintf (outf, " -="); | |
325 | break; | |
326 | case dir_star: | |
327 | fprintf (outf, " *"); | |
328 | break; | |
329 | default: | |
330 | fprintf (outf, "indep"); | |
331 | break; | |
332 | } | |
333 | } | |
334 | fprintf (outf, "\n"); | |
335 | } | |
336 | ||
ba42e045 SP |
337 | /* Print a vector of direction vectors. */ |
338 | ||
339 | void | |
340 | print_dir_vectors (FILE *outf, VEC (lambda_vector, heap) *dir_vects, | |
341 | int length) | |
342 | { | |
343 | unsigned j; | |
344 | lambda_vector v; | |
345 | ||
346 | for (j = 0; VEC_iterate (lambda_vector, dir_vects, j, v); j++) | |
347 | print_direction_vector (outf, v, length); | |
348 | } | |
349 | ||
350 | /* Print a vector of distance vectors. */ | |
351 | ||
352 | void | |
353 | print_dist_vectors (FILE *outf, VEC (lambda_vector, heap) *dist_vects, | |
354 | int length) | |
355 | { | |
356 | unsigned j; | |
357 | lambda_vector v; | |
358 | ||
359 | for (j = 0; VEC_iterate (lambda_vector, dist_vects, j, v); j++) | |
360 | print_lambda_vector (outf, v, length); | |
361 | } | |
362 | ||
363 | /* Debug version. */ | |
364 | ||
365 | void | |
366 | debug_data_dependence_relation (struct data_dependence_relation *ddr) | |
367 | { | |
368 | dump_data_dependence_relation (stderr, ddr); | |
369 | } | |
370 | ||
56cf8686 SP |
371 | /* Dump function for a DATA_DEPENDENCE_RELATION structure. */ |
372 | ||
373 | void | |
374 | dump_data_dependence_relation (FILE *outf, | |
375 | struct data_dependence_relation *ddr) | |
376 | { | |
56cf8686 | 377 | struct data_reference *dra, *drb; |
86df10e3 | 378 | |
86df10e3 | 379 | fprintf (outf, "(Data Dep: \n"); |
dea61d92 | 380 | |
ed2024ba MJ |
381 | if (!ddr || DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) |
382 | { | |
383 | fprintf (outf, " (don't know)\n)\n"); | |
384 | return; | |
385 | } | |
386 | ||
387 | dra = DDR_A (ddr); | |
388 | drb = DDR_B (ddr); | |
dea61d92 SP |
389 | dump_data_reference (outf, dra); |
390 | dump_data_reference (outf, drb); | |
391 | ||
ed2024ba | 392 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
56cf8686 SP |
393 | fprintf (outf, " (no dependence)\n"); |
394 | ||
86df10e3 | 395 | else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
56cf8686 | 396 | { |
86df10e3 | 397 | unsigned int i; |
ba42e045 | 398 | struct loop *loopi; |
304afda6 | 399 | |
56cf8686 SP |
400 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
401 | { | |
56cf8686 SP |
402 | fprintf (outf, " access_fn_A: "); |
403 | print_generic_stmt (outf, DR_ACCESS_FN (dra, i), 0); | |
404 | fprintf (outf, " access_fn_B: "); | |
405 | print_generic_stmt (outf, DR_ACCESS_FN (drb, i), 0); | |
86df10e3 | 406 | dump_subscript (outf, DDR_SUBSCRIPT (ddr, i)); |
56cf8686 | 407 | } |
304afda6 | 408 | |
3d8864c0 | 409 | fprintf (outf, " inner loop index: %d\n", DDR_INNER_LOOP (ddr)); |
ba42e045 SP |
410 | fprintf (outf, " loop nest: ("); |
411 | for (i = 0; VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++) | |
412 | fprintf (outf, "%d ", loopi->num); | |
413 | fprintf (outf, ")\n"); | |
414 | ||
304afda6 | 415 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) |
56cf8686 | 416 | { |
304afda6 SP |
417 | fprintf (outf, " distance_vector: "); |
418 | print_lambda_vector (outf, DDR_DIST_VECT (ddr, i), | |
ba42e045 | 419 | DDR_NB_LOOPS (ddr)); |
86df10e3 | 420 | } |
304afda6 SP |
421 | |
422 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
86df10e3 | 423 | { |
304afda6 | 424 | fprintf (outf, " direction_vector: "); |
0ff4040e | 425 | print_direction_vector (outf, DDR_DIR_VECT (ddr, i), |
ba42e045 | 426 | DDR_NB_LOOPS (ddr)); |
56cf8686 | 427 | } |
56cf8686 SP |
428 | } |
429 | ||
430 | fprintf (outf, ")\n"); | |
431 | } | |
432 | ||
56cf8686 SP |
433 | /* Dump function for a DATA_DEPENDENCE_DIRECTION structure. */ |
434 | ||
435 | void | |
436 | dump_data_dependence_direction (FILE *file, | |
437 | enum data_dependence_direction dir) | |
438 | { | |
439 | switch (dir) | |
440 | { | |
441 | case dir_positive: | |
442 | fprintf (file, "+"); | |
443 | break; | |
444 | ||
445 | case dir_negative: | |
446 | fprintf (file, "-"); | |
447 | break; | |
448 | ||
449 | case dir_equal: | |
450 | fprintf (file, "="); | |
451 | break; | |
452 | ||
453 | case dir_positive_or_negative: | |
454 | fprintf (file, "+-"); | |
455 | break; | |
456 | ||
457 | case dir_positive_or_equal: | |
458 | fprintf (file, "+="); | |
459 | break; | |
460 | ||
461 | case dir_negative_or_equal: | |
462 | fprintf (file, "-="); | |
463 | break; | |
464 | ||
465 | case dir_star: | |
466 | fprintf (file, "*"); | |
467 | break; | |
468 | ||
469 | default: | |
470 | break; | |
471 | } | |
472 | } | |
473 | ||
86df10e3 SP |
474 | /* Dumps the distance and direction vectors in FILE. DDRS contains |
475 | the dependence relations, and VECT_SIZE is the size of the | |
476 | dependence vectors, or in other words the number of loops in the | |
477 | considered nest. */ | |
478 | ||
479 | void | |
ebf78a47 | 480 | dump_dist_dir_vectors (FILE *file, VEC (ddr_p, heap) *ddrs) |
86df10e3 | 481 | { |
304afda6 | 482 | unsigned int i, j; |
ebf78a47 SP |
483 | struct data_dependence_relation *ddr; |
484 | lambda_vector v; | |
86df10e3 | 485 | |
ebf78a47 SP |
486 | for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) |
487 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_AFFINE_P (ddr)) | |
488 | { | |
489 | for (j = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), j, v); j++) | |
490 | { | |
491 | fprintf (file, "DISTANCE_V ("); | |
492 | print_lambda_vector (file, v, DDR_NB_LOOPS (ddr)); | |
493 | fprintf (file, ")\n"); | |
494 | } | |
495 | ||
496 | for (j = 0; VEC_iterate (lambda_vector, DDR_DIR_VECTS (ddr), j, v); j++) | |
497 | { | |
498 | fprintf (file, "DIRECTION_V ("); | |
499 | print_direction_vector (file, v, DDR_NB_LOOPS (ddr)); | |
500 | fprintf (file, ")\n"); | |
501 | } | |
502 | } | |
304afda6 | 503 | |
86df10e3 SP |
504 | fprintf (file, "\n\n"); |
505 | } | |
506 | ||
507 | /* Dumps the data dependence relations DDRS in FILE. */ | |
508 | ||
509 | void | |
ebf78a47 | 510 | dump_ddrs (FILE *file, VEC (ddr_p, heap) *ddrs) |
86df10e3 SP |
511 | { |
512 | unsigned int i; | |
ebf78a47 SP |
513 | struct data_dependence_relation *ddr; |
514 | ||
515 | for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) | |
516 | dump_data_dependence_relation (file, ddr); | |
86df10e3 | 517 | |
86df10e3 SP |
518 | fprintf (file, "\n\n"); |
519 | } | |
520 | ||
726a989a RB |
521 | /* Helper function for split_constant_offset. Expresses OP0 CODE OP1 |
522 | (the type of the result is TYPE) as VAR + OFF, where OFF is a nonzero | |
523 | constant of type ssizetype, and returns true. If we cannot do this | |
524 | with OFF nonzero, OFF and VAR are set to NULL_TREE instead and false | |
525 | is returned. */ | |
86a07404 | 526 | |
726a989a RB |
527 | static bool |
528 | split_constant_offset_1 (tree type, tree op0, enum tree_code code, tree op1, | |
529 | tree *var, tree *off) | |
86a07404 | 530 | { |
3cb960c7 ZD |
531 | tree var0, var1; |
532 | tree off0, off1; | |
726a989a | 533 | enum tree_code ocode = code; |
86a07404 | 534 | |
726a989a RB |
535 | *var = NULL_TREE; |
536 | *off = NULL_TREE; | |
86a07404 | 537 | |
5be014d5 | 538 | switch (code) |
86a07404 | 539 | { |
3cb960c7 ZD |
540 | case INTEGER_CST: |
541 | *var = build_int_cst (type, 0); | |
726a989a RB |
542 | *off = fold_convert (ssizetype, op0); |
543 | return true; | |
86a07404 | 544 | |
5be014d5 | 545 | case POINTER_PLUS_EXPR: |
726a989a | 546 | ocode = PLUS_EXPR; |
5be014d5 | 547 | /* FALLTHROUGH */ |
3cb960c7 ZD |
548 | case PLUS_EXPR: |
549 | case MINUS_EXPR: | |
726a989a RB |
550 | split_constant_offset (op0, &var0, &off0); |
551 | split_constant_offset (op1, &var1, &off1); | |
552 | *var = fold_build2 (code, type, var0, var1); | |
553 | *off = size_binop (ocode, off0, off1); | |
554 | return true; | |
86a07404 | 555 | |
86a07404 | 556 | case MULT_EXPR: |
726a989a RB |
557 | if (TREE_CODE (op1) != INTEGER_CST) |
558 | return false; | |
3cb960c7 | 559 | |
726a989a RB |
560 | split_constant_offset (op0, &var0, &off0); |
561 | *var = fold_build2 (MULT_EXPR, type, var0, op1); | |
562 | *off = size_binop (MULT_EXPR, off0, fold_convert (ssizetype, op1)); | |
563 | return true; | |
86a07404 | 564 | |
3cb960c7 ZD |
565 | case ADDR_EXPR: |
566 | { | |
726a989a | 567 | tree base, poffset; |
3cb960c7 ZD |
568 | HOST_WIDE_INT pbitsize, pbitpos; |
569 | enum machine_mode pmode; | |
570 | int punsignedp, pvolatilep; | |
86a07404 | 571 | |
da4b6efc | 572 | op0 = TREE_OPERAND (op0, 0); |
726a989a RB |
573 | if (!handled_component_p (op0)) |
574 | return false; | |
86a07404 | 575 | |
726a989a | 576 | base = get_inner_reference (op0, &pbitsize, &pbitpos, &poffset, |
3cb960c7 | 577 | &pmode, &punsignedp, &pvolatilep, false); |
86a07404 | 578 | |
3cb960c7 | 579 | if (pbitpos % BITS_PER_UNIT != 0) |
726a989a | 580 | return false; |
3cb960c7 ZD |
581 | base = build_fold_addr_expr (base); |
582 | off0 = ssize_int (pbitpos / BITS_PER_UNIT); | |
86a07404 | 583 | |
3cb960c7 ZD |
584 | if (poffset) |
585 | { | |
586 | split_constant_offset (poffset, &poffset, &off1); | |
587 | off0 = size_binop (PLUS_EXPR, off0, off1); | |
36ad7922 JJ |
588 | if (POINTER_TYPE_P (TREE_TYPE (base))) |
589 | base = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (base), | |
590 | base, fold_convert (sizetype, poffset)); | |
591 | else | |
592 | base = fold_build2 (PLUS_EXPR, TREE_TYPE (base), base, | |
593 | fold_convert (TREE_TYPE (base), poffset)); | |
3cb960c7 ZD |
594 | } |
595 | ||
6481b879 JJ |
596 | var0 = fold_convert (type, base); |
597 | ||
598 | /* If variable length types are involved, punt, otherwise casts | |
599 | might be converted into ARRAY_REFs in gimplify_conversion. | |
600 | To compute that ARRAY_REF's element size TYPE_SIZE_UNIT, which | |
601 | possibly no longer appears in current GIMPLE, might resurface. | |
602 | This perhaps could run | |
1a87cf0c | 603 | if (CONVERT_EXPR_P (var0)) |
6481b879 JJ |
604 | { |
605 | gimplify_conversion (&var0); | |
606 | // Attempt to fill in any within var0 found ARRAY_REF's | |
607 | // element size from corresponding op embedded ARRAY_REF, | |
608 | // if unsuccessful, just punt. | |
609 | } */ | |
610 | while (POINTER_TYPE_P (type)) | |
611 | type = TREE_TYPE (type); | |
612 | if (int_size_in_bytes (type) < 0) | |
726a989a | 613 | return false; |
6481b879 JJ |
614 | |
615 | *var = var0; | |
3cb960c7 | 616 | *off = off0; |
726a989a | 617 | return true; |
3cb960c7 | 618 | } |
86a07404 | 619 | |
06cb4f79 JS |
620 | case SSA_NAME: |
621 | { | |
726a989a RB |
622 | gimple def_stmt = SSA_NAME_DEF_STMT (op0); |
623 | enum tree_code subcode; | |
06cb4f79 | 624 | |
726a989a RB |
625 | if (gimple_code (def_stmt) != GIMPLE_ASSIGN) |
626 | return false; | |
627 | ||
628 | var0 = gimple_assign_rhs1 (def_stmt); | |
629 | subcode = gimple_assign_rhs_code (def_stmt); | |
630 | var1 = gimple_assign_rhs2 (def_stmt); | |
631 | ||
632 | return split_constant_offset_1 (type, var0, subcode, var1, var, off); | |
06cb4f79 JS |
633 | } |
634 | ||
86a07404 | 635 | default: |
726a989a | 636 | return false; |
86a07404 | 637 | } |
726a989a RB |
638 | } |
639 | ||
640 | /* Expresses EXP as VAR + OFF, where off is a constant. The type of OFF | |
641 | will be ssizetype. */ | |
642 | ||
643 | void | |
644 | split_constant_offset (tree exp, tree *var, tree *off) | |
645 | { | |
646 | tree type = TREE_TYPE (exp), otype, op0, op1, e, o; | |
647 | enum tree_code code; | |
86a07404 | 648 | |
726a989a | 649 | *var = exp; |
3cb960c7 | 650 | *off = ssize_int (0); |
726a989a RB |
651 | STRIP_NOPS (exp); |
652 | ||
653 | if (automatically_generated_chrec_p (exp)) | |
654 | return; | |
655 | ||
656 | otype = TREE_TYPE (exp); | |
657 | code = TREE_CODE (exp); | |
658 | extract_ops_from_tree (exp, &code, &op0, &op1); | |
659 | if (split_constant_offset_1 (otype, op0, code, op1, &e, &o)) | |
660 | { | |
661 | *var = fold_convert (type, e); | |
662 | *off = o; | |
663 | } | |
86a07404 IR |
664 | } |
665 | ||
3cb960c7 ZD |
666 | /* Returns the address ADDR of an object in a canonical shape (without nop |
667 | casts, and with type of pointer to the object). */ | |
86a07404 IR |
668 | |
669 | static tree | |
3cb960c7 | 670 | canonicalize_base_object_address (tree addr) |
86a07404 | 671 | { |
bbc8a8dc ZD |
672 | tree orig = addr; |
673 | ||
3cb960c7 | 674 | STRIP_NOPS (addr); |
86a07404 | 675 | |
bbc8a8dc ZD |
676 | /* The base address may be obtained by casting from integer, in that case |
677 | keep the cast. */ | |
678 | if (!POINTER_TYPE_P (TREE_TYPE (addr))) | |
679 | return orig; | |
680 | ||
3cb960c7 ZD |
681 | if (TREE_CODE (addr) != ADDR_EXPR) |
682 | return addr; | |
86a07404 | 683 | |
3cb960c7 | 684 | return build_fold_addr_expr (TREE_OPERAND (addr, 0)); |
86a07404 IR |
685 | } |
686 | ||
a70d6342 IR |
687 | /* Analyzes the behavior of the memory reference DR in the innermost loop or |
688 | basic block that contains it. Returns true if analysis succeed or false | |
689 | otherwise. */ | |
86a07404 | 690 | |
3661e899 | 691 | bool |
3cb960c7 | 692 | dr_analyze_innermost (struct data_reference *dr) |
86a07404 | 693 | { |
726a989a | 694 | gimple stmt = DR_STMT (dr); |
3cb960c7 ZD |
695 | struct loop *loop = loop_containing_stmt (stmt); |
696 | tree ref = DR_REF (dr); | |
86a07404 | 697 | HOST_WIDE_INT pbitsize, pbitpos; |
3cb960c7 | 698 | tree base, poffset; |
86a07404 IR |
699 | enum machine_mode pmode; |
700 | int punsignedp, pvolatilep; | |
3cb960c7 ZD |
701 | affine_iv base_iv, offset_iv; |
702 | tree init, dinit, step; | |
a70d6342 | 703 | bool in_loop = (loop && loop->num); |
3cb960c7 ZD |
704 | |
705 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
706 | fprintf (dump_file, "analyze_innermost: "); | |
86a07404 | 707 | |
3cb960c7 ZD |
708 | base = get_inner_reference (ref, &pbitsize, &pbitpos, &poffset, |
709 | &pmode, &punsignedp, &pvolatilep, false); | |
710 | gcc_assert (base != NULL_TREE); | |
86a07404 | 711 | |
3cb960c7 | 712 | if (pbitpos % BITS_PER_UNIT != 0) |
86a07404 | 713 | { |
3cb960c7 ZD |
714 | if (dump_file && (dump_flags & TDF_DETAILS)) |
715 | fprintf (dump_file, "failed: bit offset alignment.\n"); | |
3661e899 | 716 | return false; |
3cb960c7 | 717 | } |
86a07404 | 718 | |
3cb960c7 | 719 | base = build_fold_addr_expr (base); |
a70d6342 | 720 | if (in_loop) |
3cb960c7 | 721 | { |
a70d6342 IR |
722 | if (!simple_iv (loop, loop_containing_stmt (stmt), base, &base_iv, |
723 | false)) | |
724 | { | |
725 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
726 | fprintf (dump_file, "failed: evolution of base is not affine.\n"); | |
727 | return false; | |
728 | } | |
729 | } | |
730 | else | |
731 | { | |
732 | base_iv.base = base; | |
733 | base_iv.step = ssize_int (0); | |
734 | base_iv.no_overflow = true; | |
3cb960c7 | 735 | } |
a70d6342 | 736 | |
24adb18f | 737 | if (!poffset) |
3cb960c7 ZD |
738 | { |
739 | offset_iv.base = ssize_int (0); | |
740 | offset_iv.step = ssize_int (0); | |
741 | } | |
24adb18f | 742 | else |
3cb960c7 | 743 | { |
24adb18f IR |
744 | if (!in_loop) |
745 | { | |
746 | offset_iv.base = poffset; | |
747 | offset_iv.step = ssize_int (0); | |
748 | } | |
749 | else if (!simple_iv (loop, loop_containing_stmt (stmt), | |
750 | poffset, &offset_iv, false)) | |
751 | { | |
752 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
753 | fprintf (dump_file, "failed: evolution of offset is not" | |
754 | " affine.\n"); | |
755 | return false; | |
756 | } | |
3cb960c7 | 757 | } |
86a07404 | 758 | |
3cb960c7 ZD |
759 | init = ssize_int (pbitpos / BITS_PER_UNIT); |
760 | split_constant_offset (base_iv.base, &base_iv.base, &dinit); | |
761 | init = size_binop (PLUS_EXPR, init, dinit); | |
762 | split_constant_offset (offset_iv.base, &offset_iv.base, &dinit); | |
763 | init = size_binop (PLUS_EXPR, init, dinit); | |
86a07404 | 764 | |
3cb960c7 ZD |
765 | step = size_binop (PLUS_EXPR, |
766 | fold_convert (ssizetype, base_iv.step), | |
767 | fold_convert (ssizetype, offset_iv.step)); | |
86a07404 | 768 | |
3cb960c7 | 769 | DR_BASE_ADDRESS (dr) = canonicalize_base_object_address (base_iv.base); |
86a07404 | 770 | |
3cb960c7 ZD |
771 | DR_OFFSET (dr) = fold_convert (ssizetype, offset_iv.base); |
772 | DR_INIT (dr) = init; | |
773 | DR_STEP (dr) = step; | |
86a07404 | 774 | |
3cb960c7 | 775 | DR_ALIGNED_TO (dr) = size_int (highest_pow2_factor (offset_iv.base)); |
86a07404 | 776 | |
3cb960c7 ZD |
777 | if (dump_file && (dump_flags & TDF_DETAILS)) |
778 | fprintf (dump_file, "success.\n"); | |
3661e899 TB |
779 | |
780 | return true; | |
3cb960c7 | 781 | } |
86a07404 | 782 | |
3cb960c7 | 783 | /* Determines the base object and the list of indices of memory reference |
c80b4100 | 784 | DR, analyzed in loop nest NEST. */ |
86a07404 | 785 | |
3cb960c7 ZD |
786 | static void |
787 | dr_analyze_indices (struct data_reference *dr, struct loop *nest) | |
788 | { | |
726a989a | 789 | gimple stmt = DR_STMT (dr); |
3cb960c7 ZD |
790 | struct loop *loop = loop_containing_stmt (stmt); |
791 | VEC (tree, heap) *access_fns = NULL; | |
792 | tree ref = unshare_expr (DR_REF (dr)), aref = ref, op; | |
a70d6342 IR |
793 | tree base, off, access_fn = NULL_TREE; |
794 | basic_block before_loop = NULL; | |
795 | ||
796 | if (nest) | |
797 | before_loop = block_before_loop (nest); | |
798 | ||
3cb960c7 | 799 | while (handled_component_p (aref)) |
86a07404 | 800 | { |
3cb960c7 | 801 | if (TREE_CODE (aref) == ARRAY_REF) |
86a07404 | 802 | { |
3cb960c7 | 803 | op = TREE_OPERAND (aref, 1); |
a70d6342 IR |
804 | if (nest) |
805 | { | |
806 | access_fn = analyze_scalar_evolution (loop, op); | |
807 | access_fn = instantiate_scev (before_loop, loop, access_fn); | |
808 | VEC_safe_push (tree, heap, access_fns, access_fn); | |
809 | } | |
3cb960c7 ZD |
810 | |
811 | TREE_OPERAND (aref, 1) = build_int_cst (TREE_TYPE (op), 0); | |
86a07404 | 812 | } |
3cb960c7 ZD |
813 | |
814 | aref = TREE_OPERAND (aref, 0); | |
86a07404 IR |
815 | } |
816 | ||
a70d6342 | 817 | if (nest && INDIRECT_REF_P (aref)) |
86a07404 | 818 | { |
3cb960c7 ZD |
819 | op = TREE_OPERAND (aref, 0); |
820 | access_fn = analyze_scalar_evolution (loop, op); | |
a213b219 | 821 | access_fn = instantiate_scev (before_loop, loop, access_fn); |
3cb960c7 ZD |
822 | base = initial_condition (access_fn); |
823 | split_constant_offset (base, &base, &off); | |
824 | access_fn = chrec_replace_initial_condition (access_fn, | |
825 | fold_convert (TREE_TYPE (base), off)); | |
826 | ||
827 | TREE_OPERAND (aref, 0) = base; | |
828 | VEC_safe_push (tree, heap, access_fns, access_fn); | |
86a07404 | 829 | } |
86a07404 | 830 | |
3cb960c7 ZD |
831 | DR_BASE_OBJECT (dr) = ref; |
832 | DR_ACCESS_FNS (dr) = access_fns; | |
86a07404 IR |
833 | } |
834 | ||
3cb960c7 | 835 | /* Extracts the alias analysis information from the memory reference DR. */ |
86a07404 | 836 | |
3cb960c7 ZD |
837 | static void |
838 | dr_analyze_alias (struct data_reference *dr) | |
86a07404 | 839 | { |
3cb960c7 | 840 | tree ref = DR_REF (dr); |
5006671f RG |
841 | tree base = get_base_address (ref), addr; |
842 | ||
843 | if (INDIRECT_REF_P (base)) | |
3cb960c7 ZD |
844 | { |
845 | addr = TREE_OPERAND (base, 0); | |
846 | if (TREE_CODE (addr) == SSA_NAME) | |
5006671f | 847 | DR_PTR_INFO (dr) = SSA_NAME_PTR_INFO (addr); |
3cb960c7 | 848 | } |
3cb960c7 | 849 | } |
86a07404 | 850 | |
3cb960c7 | 851 | /* Returns true if the address of DR is invariant. */ |
86a07404 | 852 | |
3cb960c7 ZD |
853 | static bool |
854 | dr_address_invariant_p (struct data_reference *dr) | |
855 | { | |
856 | unsigned i; | |
857 | tree idx; | |
858 | ||
859 | for (i = 0; VEC_iterate (tree, DR_ACCESS_FNS (dr), i, idx); i++) | |
860 | if (tree_contains_chrecs (idx, NULL)) | |
861 | return false; | |
e838422b | 862 | |
e838422b | 863 | return true; |
86a07404 IR |
864 | } |
865 | ||
3cb960c7 | 866 | /* Frees data reference DR. */ |
8fdbc9c6 | 867 | |
dea61d92 | 868 | void |
8fdbc9c6 ZD |
869 | free_data_ref (data_reference_p dr) |
870 | { | |
3cb960c7 | 871 | VEC_free (tree, heap, DR_ACCESS_FNS (dr)); |
8fdbc9c6 ZD |
872 | free (dr); |
873 | } | |
86a07404 | 874 | |
3cb960c7 ZD |
875 | /* Analyzes memory reference MEMREF accessed in STMT. The reference |
876 | is read if IS_READ is true, write otherwise. Returns the | |
877 | data_reference description of MEMREF. NEST is the outermost loop of the | |
0d52bcc1 | 878 | loop nest in that the reference should be analyzed. */ |
86a07404 | 879 | |
5417e022 | 880 | struct data_reference * |
726a989a | 881 | create_data_ref (struct loop *nest, tree memref, gimple stmt, bool is_read) |
86a07404 | 882 | { |
3cb960c7 | 883 | struct data_reference *dr; |
0ff4040e | 884 | |
3cb960c7 | 885 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e | 886 | { |
3cb960c7 ZD |
887 | fprintf (dump_file, "Creating dr for "); |
888 | print_generic_expr (dump_file, memref, TDF_SLIM); | |
889 | fprintf (dump_file, "\n"); | |
0ff4040e | 890 | } |
e2157b49 | 891 | |
3cb960c7 ZD |
892 | dr = XCNEW (struct data_reference); |
893 | DR_STMT (dr) = stmt; | |
894 | DR_REF (dr) = memref; | |
895 | DR_IS_READ (dr) = is_read; | |
86a07404 | 896 | |
3cb960c7 ZD |
897 | dr_analyze_innermost (dr); |
898 | dr_analyze_indices (dr, nest); | |
899 | dr_analyze_alias (dr); | |
86a07404 IR |
900 | |
901 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
902 | { | |
3cb960c7 | 903 | fprintf (dump_file, "\tbase_address: "); |
86a07404 IR |
904 | print_generic_expr (dump_file, DR_BASE_ADDRESS (dr), TDF_SLIM); |
905 | fprintf (dump_file, "\n\toffset from base address: "); | |
906 | print_generic_expr (dump_file, DR_OFFSET (dr), TDF_SLIM); | |
907 | fprintf (dump_file, "\n\tconstant offset from base address: "); | |
908 | print_generic_expr (dump_file, DR_INIT (dr), TDF_SLIM); | |
86a07404 IR |
909 | fprintf (dump_file, "\n\tstep: "); |
910 | print_generic_expr (dump_file, DR_STEP (dr), TDF_SLIM); | |
3cb960c7 ZD |
911 | fprintf (dump_file, "\n\taligned to: "); |
912 | print_generic_expr (dump_file, DR_ALIGNED_TO (dr), TDF_SLIM); | |
913 | fprintf (dump_file, "\n\tbase_object: "); | |
914 | print_generic_expr (dump_file, DR_BASE_OBJECT (dr), TDF_SLIM); | |
86a07404 | 915 | fprintf (dump_file, "\n"); |
3cb960c7 ZD |
916 | } |
917 | ||
86a07404 IR |
918 | return dr; |
919 | } | |
920 | ||
d93817c4 ZD |
921 | /* Returns true if FNA == FNB. */ |
922 | ||
923 | static bool | |
924 | affine_function_equal_p (affine_fn fna, affine_fn fnb) | |
925 | { | |
926 | unsigned i, n = VEC_length (tree, fna); | |
86a07404 | 927 | |
f86289d5 ZD |
928 | if (n != VEC_length (tree, fnb)) |
929 | return false; | |
86df10e3 | 930 | |
d93817c4 ZD |
931 | for (i = 0; i < n; i++) |
932 | if (!operand_equal_p (VEC_index (tree, fna, i), | |
933 | VEC_index (tree, fnb, i), 0)) | |
934 | return false; | |
935 | ||
936 | return true; | |
937 | } | |
938 | ||
939 | /* If all the functions in CF are the same, returns one of them, | |
940 | otherwise returns NULL. */ | |
941 | ||
942 | static affine_fn | |
943 | common_affine_function (conflict_function *cf) | |
86df10e3 | 944 | { |
d93817c4 ZD |
945 | unsigned i; |
946 | affine_fn comm; | |
947 | ||
948 | if (!CF_NONTRIVIAL_P (cf)) | |
949 | return NULL; | |
950 | ||
951 | comm = cf->fns[0]; | |
952 | ||
953 | for (i = 1; i < cf->n; i++) | |
954 | if (!affine_function_equal_p (comm, cf->fns[i])) | |
955 | return NULL; | |
956 | ||
957 | return comm; | |
958 | } | |
86df10e3 | 959 | |
d93817c4 ZD |
960 | /* Returns the base of the affine function FN. */ |
961 | ||
962 | static tree | |
963 | affine_function_base (affine_fn fn) | |
964 | { | |
965 | return VEC_index (tree, fn, 0); | |
966 | } | |
967 | ||
968 | /* Returns true if FN is a constant. */ | |
969 | ||
970 | static bool | |
971 | affine_function_constant_p (affine_fn fn) | |
972 | { | |
973 | unsigned i; | |
974 | tree coef; | |
975 | ||
976 | for (i = 1; VEC_iterate (tree, fn, i, coef); i++) | |
977 | if (!integer_zerop (coef)) | |
e2157b49 SP |
978 | return false; |
979 | ||
86df10e3 SP |
980 | return true; |
981 | } | |
982 | ||
1baf2906 SP |
983 | /* Returns true if FN is the zero constant function. */ |
984 | ||
985 | static bool | |
986 | affine_function_zero_p (affine_fn fn) | |
987 | { | |
988 | return (integer_zerop (affine_function_base (fn)) | |
989 | && affine_function_constant_p (fn)); | |
990 | } | |
991 | ||
33b30201 SP |
992 | /* Returns a signed integer type with the largest precision from TA |
993 | and TB. */ | |
994 | ||
995 | static tree | |
996 | signed_type_for_types (tree ta, tree tb) | |
997 | { | |
998 | if (TYPE_PRECISION (ta) > TYPE_PRECISION (tb)) | |
999 | return signed_type_for (ta); | |
1000 | else | |
1001 | return signed_type_for (tb); | |
1002 | } | |
1003 | ||
d93817c4 ZD |
1004 | /* Applies operation OP on affine functions FNA and FNB, and returns the |
1005 | result. */ | |
1006 | ||
1007 | static affine_fn | |
1008 | affine_fn_op (enum tree_code op, affine_fn fna, affine_fn fnb) | |
1009 | { | |
1010 | unsigned i, n, m; | |
1011 | affine_fn ret; | |
1012 | tree coef; | |
1013 | ||
1014 | if (VEC_length (tree, fnb) > VEC_length (tree, fna)) | |
1015 | { | |
1016 | n = VEC_length (tree, fna); | |
1017 | m = VEC_length (tree, fnb); | |
1018 | } | |
1019 | else | |
1020 | { | |
1021 | n = VEC_length (tree, fnb); | |
1022 | m = VEC_length (tree, fna); | |
1023 | } | |
1024 | ||
1025 | ret = VEC_alloc (tree, heap, m); | |
1026 | for (i = 0; i < n; i++) | |
33b30201 SP |
1027 | { |
1028 | tree type = signed_type_for_types (TREE_TYPE (VEC_index (tree, fna, i)), | |
1029 | TREE_TYPE (VEC_index (tree, fnb, i))); | |
1030 | ||
1031 | VEC_quick_push (tree, ret, | |
1032 | fold_build2 (op, type, | |
1033 | VEC_index (tree, fna, i), | |
1034 | VEC_index (tree, fnb, i))); | |
1035 | } | |
d93817c4 ZD |
1036 | |
1037 | for (; VEC_iterate (tree, fna, i, coef); i++) | |
1038 | VEC_quick_push (tree, ret, | |
33b30201 | 1039 | fold_build2 (op, signed_type_for (TREE_TYPE (coef)), |
d93817c4 ZD |
1040 | coef, integer_zero_node)); |
1041 | for (; VEC_iterate (tree, fnb, i, coef); i++) | |
1042 | VEC_quick_push (tree, ret, | |
33b30201 | 1043 | fold_build2 (op, signed_type_for (TREE_TYPE (coef)), |
d93817c4 ZD |
1044 | integer_zero_node, coef)); |
1045 | ||
1046 | return ret; | |
1047 | } | |
1048 | ||
1049 | /* Returns the sum of affine functions FNA and FNB. */ | |
1050 | ||
1051 | static affine_fn | |
1052 | affine_fn_plus (affine_fn fna, affine_fn fnb) | |
1053 | { | |
1054 | return affine_fn_op (PLUS_EXPR, fna, fnb); | |
1055 | } | |
1056 | ||
1057 | /* Returns the difference of affine functions FNA and FNB. */ | |
1058 | ||
1059 | static affine_fn | |
1060 | affine_fn_minus (affine_fn fna, affine_fn fnb) | |
1061 | { | |
1062 | return affine_fn_op (MINUS_EXPR, fna, fnb); | |
1063 | } | |
1064 | ||
1065 | /* Frees affine function FN. */ | |
1066 | ||
1067 | static void | |
1068 | affine_fn_free (affine_fn fn) | |
1069 | { | |
1070 | VEC_free (tree, heap, fn); | |
1071 | } | |
1072 | ||
86df10e3 SP |
1073 | /* Determine for each subscript in the data dependence relation DDR |
1074 | the distance. */ | |
56cf8686 | 1075 | |
0ff4040e | 1076 | static void |
86df10e3 | 1077 | compute_subscript_distance (struct data_dependence_relation *ddr) |
56cf8686 | 1078 | { |
d93817c4 ZD |
1079 | conflict_function *cf_a, *cf_b; |
1080 | affine_fn fn_a, fn_b, diff; | |
1081 | ||
56cf8686 SP |
1082 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
1083 | { | |
1084 | unsigned int i; | |
1085 | ||
1086 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
1087 | { | |
56cf8686 SP |
1088 | struct subscript *subscript; |
1089 | ||
1090 | subscript = DDR_SUBSCRIPT (ddr, i); | |
d93817c4 ZD |
1091 | cf_a = SUB_CONFLICTS_IN_A (subscript); |
1092 | cf_b = SUB_CONFLICTS_IN_B (subscript); | |
86df10e3 | 1093 | |
d93817c4 ZD |
1094 | fn_a = common_affine_function (cf_a); |
1095 | fn_b = common_affine_function (cf_b); | |
1096 | if (!fn_a || !fn_b) | |
86df10e3 | 1097 | { |
d93817c4 ZD |
1098 | SUB_DISTANCE (subscript) = chrec_dont_know; |
1099 | return; | |
86df10e3 | 1100 | } |
d93817c4 | 1101 | diff = affine_fn_minus (fn_a, fn_b); |
56cf8686 | 1102 | |
d93817c4 ZD |
1103 | if (affine_function_constant_p (diff)) |
1104 | SUB_DISTANCE (subscript) = affine_function_base (diff); | |
56cf8686 SP |
1105 | else |
1106 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
d93817c4 ZD |
1107 | |
1108 | affine_fn_free (diff); | |
56cf8686 SP |
1109 | } |
1110 | } | |
1111 | } | |
1112 | ||
d93817c4 ZD |
1113 | /* Returns the conflict function for "unknown". */ |
1114 | ||
1115 | static conflict_function * | |
1116 | conflict_fn_not_known (void) | |
1117 | { | |
1118 | conflict_function *fn = XCNEW (conflict_function); | |
1119 | fn->n = NOT_KNOWN; | |
1120 | ||
1121 | return fn; | |
1122 | } | |
1123 | ||
1124 | /* Returns the conflict function for "independent". */ | |
1125 | ||
1126 | static conflict_function * | |
1127 | conflict_fn_no_dependence (void) | |
1128 | { | |
1129 | conflict_function *fn = XCNEW (conflict_function); | |
1130 | fn->n = NO_DEPENDENCE; | |
1131 | ||
1132 | return fn; | |
1133 | } | |
1134 | ||
3cb960c7 ZD |
1135 | /* Returns true if the address of OBJ is invariant in LOOP. */ |
1136 | ||
1137 | static bool | |
ed7a4b4b | 1138 | object_address_invariant_in_loop_p (const struct loop *loop, const_tree obj) |
3cb960c7 ZD |
1139 | { |
1140 | while (handled_component_p (obj)) | |
1141 | { | |
1142 | if (TREE_CODE (obj) == ARRAY_REF) | |
1143 | { | |
1144 | /* Index of the ARRAY_REF was zeroed in analyze_indices, thus we only | |
1145 | need to check the stride and the lower bound of the reference. */ | |
1146 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1147 | loop->num) | |
1148 | || chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 3), | |
1149 | loop->num)) | |
1150 | return false; | |
1151 | } | |
1152 | else if (TREE_CODE (obj) == COMPONENT_REF) | |
1153 | { | |
1154 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1155 | loop->num)) | |
1156 | return false; | |
1157 | } | |
1158 | obj = TREE_OPERAND (obj, 0); | |
1159 | } | |
1160 | ||
1161 | if (!INDIRECT_REF_P (obj)) | |
1162 | return true; | |
1163 | ||
1164 | return !chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 0), | |
1165 | loop->num); | |
1166 | } | |
1167 | ||
1168 | /* Returns true if A and B are accesses to different objects, or to different | |
1169 | fields of the same object. */ | |
1170 | ||
1171 | static bool | |
1172 | disjoint_objects_p (tree a, tree b) | |
1173 | { | |
1174 | tree base_a, base_b; | |
1175 | VEC (tree, heap) *comp_a = NULL, *comp_b = NULL; | |
1176 | bool ret; | |
1177 | ||
1178 | base_a = get_base_address (a); | |
1179 | base_b = get_base_address (b); | |
1180 | ||
1181 | if (DECL_P (base_a) | |
1182 | && DECL_P (base_b) | |
1183 | && base_a != base_b) | |
1184 | return true; | |
1185 | ||
1186 | if (!operand_equal_p (base_a, base_b, 0)) | |
1187 | return false; | |
1188 | ||
1189 | /* Compare the component references of A and B. We must start from the inner | |
1190 | ones, so record them to the vector first. */ | |
1191 | while (handled_component_p (a)) | |
1192 | { | |
1193 | VEC_safe_push (tree, heap, comp_a, a); | |
1194 | a = TREE_OPERAND (a, 0); | |
1195 | } | |
1196 | while (handled_component_p (b)) | |
1197 | { | |
1198 | VEC_safe_push (tree, heap, comp_b, b); | |
1199 | b = TREE_OPERAND (b, 0); | |
1200 | } | |
1201 | ||
1202 | ret = false; | |
1203 | while (1) | |
1204 | { | |
1205 | if (VEC_length (tree, comp_a) == 0 | |
1206 | || VEC_length (tree, comp_b) == 0) | |
1207 | break; | |
1208 | ||
1209 | a = VEC_pop (tree, comp_a); | |
1210 | b = VEC_pop (tree, comp_b); | |
1211 | ||
1212 | /* Real and imaginary part of a variable do not alias. */ | |
1213 | if ((TREE_CODE (a) == REALPART_EXPR | |
1214 | && TREE_CODE (b) == IMAGPART_EXPR) | |
1215 | || (TREE_CODE (a) == IMAGPART_EXPR | |
1216 | && TREE_CODE (b) == REALPART_EXPR)) | |
1217 | { | |
1218 | ret = true; | |
1219 | break; | |
1220 | } | |
1221 | ||
1222 | if (TREE_CODE (a) != TREE_CODE (b)) | |
1223 | break; | |
1224 | ||
1225 | /* Nothing to do for ARRAY_REFs, as the indices of array_refs in | |
1226 | DR_BASE_OBJECT are always zero. */ | |
1227 | if (TREE_CODE (a) == ARRAY_REF) | |
1228 | continue; | |
1229 | else if (TREE_CODE (a) == COMPONENT_REF) | |
1230 | { | |
1231 | if (operand_equal_p (TREE_OPERAND (a, 1), TREE_OPERAND (b, 1), 0)) | |
1232 | continue; | |
1233 | ||
1234 | /* Different fields of unions may overlap. */ | |
1235 | base_a = TREE_OPERAND (a, 0); | |
1236 | if (TREE_CODE (TREE_TYPE (base_a)) == UNION_TYPE) | |
1237 | break; | |
1238 | ||
1239 | /* Different fields of structures cannot. */ | |
1240 | ret = true; | |
1241 | break; | |
1242 | } | |
1243 | else | |
1244 | break; | |
1245 | } | |
1246 | ||
1247 | VEC_free (tree, heap, comp_a); | |
1248 | VEC_free (tree, heap, comp_b); | |
1249 | ||
1250 | return ret; | |
1251 | } | |
1252 | ||
1253 | /* Returns false if we can prove that data references A and B do not alias, | |
1254 | true otherwise. */ | |
1255 | ||
f8bf9252 | 1256 | bool |
ed7a4b4b | 1257 | dr_may_alias_p (const struct data_reference *a, const struct data_reference *b) |
3cb960c7 | 1258 | { |
ed7a4b4b KG |
1259 | const_tree addr_a = DR_BASE_ADDRESS (a); |
1260 | const_tree addr_b = DR_BASE_ADDRESS (b); | |
1261 | const_tree type_a, type_b; | |
1262 | const_tree decl_a = NULL_TREE, decl_b = NULL_TREE; | |
3cb960c7 | 1263 | |
3cb960c7 ZD |
1264 | /* If the accessed objects are disjoint, the memory references do not |
1265 | alias. */ | |
1266 | if (disjoint_objects_p (DR_BASE_OBJECT (a), DR_BASE_OBJECT (b))) | |
1267 | return false; | |
1268 | ||
5006671f | 1269 | /* Query the alias oracle. */ |
4d7a65ea RG |
1270 | if (!DR_IS_READ (a) && !DR_IS_READ (b)) |
1271 | { | |
1272 | if (!refs_output_dependent_p (DR_REF (a), DR_REF (b))) | |
1273 | return false; | |
1274 | } | |
1275 | else if (DR_IS_READ (a) && !DR_IS_READ (b)) | |
1276 | { | |
1277 | if (!refs_anti_dependent_p (DR_REF (a), DR_REF (b))) | |
1278 | return false; | |
1279 | } | |
1280 | else if (!refs_may_alias_p (DR_REF (a), DR_REF (b))) | |
5006671f RG |
1281 | return false; |
1282 | ||
3cb960c7 ZD |
1283 | if (!addr_a || !addr_b) |
1284 | return true; | |
1285 | ||
5006671f RG |
1286 | /* If the references are based on different static objects, they cannot |
1287 | alias (PTA should be able to disambiguate such accesses, but often | |
1288 | it fails to). */ | |
3cb960c7 ZD |
1289 | if (TREE_CODE (addr_a) == ADDR_EXPR |
1290 | && TREE_CODE (addr_b) == ADDR_EXPR) | |
1291 | return TREE_OPERAND (addr_a, 0) == TREE_OPERAND (addr_b, 0); | |
1292 | ||
1293 | /* An instruction writing through a restricted pointer is "independent" of any | |
1294 | instruction reading or writing through a different restricted pointer, | |
1295 | in the same block/scope. */ | |
1296 | ||
1297 | type_a = TREE_TYPE (addr_a); | |
1298 | type_b = TREE_TYPE (addr_b); | |
1299 | gcc_assert (POINTER_TYPE_P (type_a) && POINTER_TYPE_P (type_b)); | |
1300 | ||
1301 | if (TREE_CODE (addr_a) == SSA_NAME) | |
1302 | decl_a = SSA_NAME_VAR (addr_a); | |
1303 | if (TREE_CODE (addr_b) == SSA_NAME) | |
1304 | decl_b = SSA_NAME_VAR (addr_b); | |
1305 | ||
1306 | if (TYPE_RESTRICT (type_a) && TYPE_RESTRICT (type_b) | |
1307 | && (!DR_IS_READ (a) || !DR_IS_READ (b)) | |
55edccf4 DB |
1308 | && decl_a && DECL_P (decl_a) |
1309 | && decl_b && DECL_P (decl_b) | |
1310 | && decl_a != decl_b | |
3cb960c7 ZD |
1311 | && TREE_CODE (DECL_CONTEXT (decl_a)) == FUNCTION_DECL |
1312 | && DECL_CONTEXT (decl_a) == DECL_CONTEXT (decl_b)) | |
1313 | return false; | |
1314 | ||
1315 | return true; | |
1316 | } | |
1317 | ||
b3924be9 SP |
1318 | static void compute_self_dependence (struct data_dependence_relation *); |
1319 | ||
0ff4040e SP |
1320 | /* Initialize a data dependence relation between data accesses A and |
1321 | B. NB_LOOPS is the number of loops surrounding the references: the | |
1322 | size of the classic distance/direction vectors. */ | |
56cf8686 | 1323 | |
0ff4040e | 1324 | static struct data_dependence_relation * |
56cf8686 | 1325 | initialize_data_dependence_relation (struct data_reference *a, |
0ff4040e | 1326 | struct data_reference *b, |
ba42e045 | 1327 | VEC (loop_p, heap) *loop_nest) |
56cf8686 SP |
1328 | { |
1329 | struct data_dependence_relation *res; | |
0ff4040e | 1330 | unsigned int i; |
56cf8686 | 1331 | |
5ed6ace5 | 1332 | res = XNEW (struct data_dependence_relation); |
56cf8686 SP |
1333 | DDR_A (res) = a; |
1334 | DDR_B (res) = b; | |
3ac57120 | 1335 | DDR_LOOP_NEST (res) = NULL; |
71d5b5e1 | 1336 | DDR_REVERSED_P (res) = false; |
2f470326 JJ |
1337 | DDR_SUBSCRIPTS (res) = NULL; |
1338 | DDR_DIR_VECTS (res) = NULL; | |
1339 | DDR_DIST_VECTS (res) = NULL; | |
56cf8686 | 1340 | |
86a07404 IR |
1341 | if (a == NULL || b == NULL) |
1342 | { | |
1343 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1344 | return res; | |
1345 | } | |
1346 | ||
3cb960c7 ZD |
1347 | /* If the data references do not alias, then they are independent. */ |
1348 | if (!dr_may_alias_p (a, b)) | |
86a07404 | 1349 | { |
3cb960c7 | 1350 | DDR_ARE_DEPENDENT (res) = chrec_known; |
86a07404 IR |
1351 | return res; |
1352 | } | |
56cf8686 | 1353 | |
b3924be9 SP |
1354 | /* When the references are exactly the same, don't spend time doing |
1355 | the data dependence tests, just initialize the ddr and return. */ | |
1356 | if (operand_equal_p (DR_REF (a), DR_REF (b), 0)) | |
1357 | { | |
1358 | DDR_AFFINE_P (res) = true; | |
1359 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
1360 | DDR_SUBSCRIPTS (res) = VEC_alloc (subscript_p, heap, DR_NUM_DIMENSIONS (a)); | |
1361 | DDR_LOOP_NEST (res) = loop_nest; | |
1362 | DDR_INNER_LOOP (res) = 0; | |
1363 | DDR_SELF_REFERENCE (res) = true; | |
1364 | compute_self_dependence (res); | |
1365 | return res; | |
1366 | } | |
1367 | ||
3cb960c7 ZD |
1368 | /* If the references do not access the same object, we do not know |
1369 | whether they alias or not. */ | |
1370 | if (!operand_equal_p (DR_BASE_OBJECT (a), DR_BASE_OBJECT (b), 0)) | |
56cf8686 | 1371 | { |
86a07404 IR |
1372 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
1373 | return res; | |
1374 | } | |
0ff4040e | 1375 | |
3cb960c7 | 1376 | /* If the base of the object is not invariant in the loop nest, we cannot |
0d52bcc1 | 1377 | analyze it. TODO -- in fact, it would suffice to record that there may |
c80b4100 | 1378 | be arbitrary dependences in the loops where the base object varies. */ |
a70d6342 IR |
1379 | if (loop_nest |
1380 | && !object_address_invariant_in_loop_p (VEC_index (loop_p, loop_nest, 0), | |
1381 | DR_BASE_OBJECT (a))) | |
86a07404 | 1382 | { |
3cb960c7 | 1383 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1384 | return res; |
1385 | } | |
3cb960c7 ZD |
1386 | |
1387 | gcc_assert (DR_NUM_DIMENSIONS (a) == DR_NUM_DIMENSIONS (b)); | |
1388 | ||
86a07404 IR |
1389 | DDR_AFFINE_P (res) = true; |
1390 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
ebf78a47 | 1391 | DDR_SUBSCRIPTS (res) = VEC_alloc (subscript_p, heap, DR_NUM_DIMENSIONS (a)); |
ba42e045 | 1392 | DDR_LOOP_NEST (res) = loop_nest; |
3d8864c0 | 1393 | DDR_INNER_LOOP (res) = 0; |
b3924be9 | 1394 | DDR_SELF_REFERENCE (res) = false; |
304afda6 | 1395 | |
86a07404 IR |
1396 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1397 | { | |
1398 | struct subscript *subscript; | |
56cf8686 | 1399 | |
5ed6ace5 | 1400 | subscript = XNEW (struct subscript); |
d93817c4 ZD |
1401 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); |
1402 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
86a07404 IR |
1403 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
1404 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
ebf78a47 | 1405 | VEC_safe_push (subscript_p, heap, DDR_SUBSCRIPTS (res), subscript); |
56cf8686 | 1406 | } |
ebf78a47 | 1407 | |
56cf8686 SP |
1408 | return res; |
1409 | } | |
1410 | ||
d93817c4 ZD |
1411 | /* Frees memory used by the conflict function F. */ |
1412 | ||
1413 | static void | |
1414 | free_conflict_function (conflict_function *f) | |
1415 | { | |
1416 | unsigned i; | |
1417 | ||
1418 | if (CF_NONTRIVIAL_P (f)) | |
1419 | { | |
1420 | for (i = 0; i < f->n; i++) | |
1421 | affine_fn_free (f->fns[i]); | |
1422 | } | |
1423 | free (f); | |
1424 | } | |
1425 | ||
1426 | /* Frees memory used by SUBSCRIPTS. */ | |
1427 | ||
1428 | static void | |
1429 | free_subscripts (VEC (subscript_p, heap) *subscripts) | |
1430 | { | |
1431 | unsigned i; | |
1432 | subscript_p s; | |
1433 | ||
1434 | for (i = 0; VEC_iterate (subscript_p, subscripts, i, s); i++) | |
1435 | { | |
1436 | free_conflict_function (s->conflicting_iterations_in_a); | |
1437 | free_conflict_function (s->conflicting_iterations_in_b); | |
a0044be5 | 1438 | free (s); |
d93817c4 ZD |
1439 | } |
1440 | VEC_free (subscript_p, heap, subscripts); | |
1441 | } | |
1442 | ||
56cf8686 SP |
1443 | /* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap |
1444 | description. */ | |
1445 | ||
1446 | static inline void | |
1447 | finalize_ddr_dependent (struct data_dependence_relation *ddr, | |
1448 | tree chrec) | |
1449 | { | |
36d59cf7 DB |
1450 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1451 | { | |
1452 | fprintf (dump_file, "(dependence classified: "); | |
1453 | print_generic_expr (dump_file, chrec, 0); | |
1454 | fprintf (dump_file, ")\n"); | |
1455 | } | |
1456 | ||
56cf8686 | 1457 | DDR_ARE_DEPENDENT (ddr) = chrec; |
d93817c4 | 1458 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
2f470326 | 1459 | DDR_SUBSCRIPTS (ddr) = NULL; |
56cf8686 SP |
1460 | } |
1461 | ||
86df10e3 SP |
1462 | /* The dependence relation DDR cannot be represented by a distance |
1463 | vector. */ | |
1464 | ||
1465 | static inline void | |
1466 | non_affine_dependence_relation (struct data_dependence_relation *ddr) | |
1467 | { | |
1468 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1469 | fprintf (dump_file, "(Dependence relation cannot be represented by distance vector.) \n"); | |
1470 | ||
1471 | DDR_AFFINE_P (ddr) = false; | |
1472 | } | |
1473 | ||
56cf8686 SP |
1474 | \f |
1475 | ||
1476 | /* This section contains the classic Banerjee tests. */ | |
1477 | ||
1478 | /* Returns true iff CHREC_A and CHREC_B are not dependent on any index | |
1479 | variables, i.e., if the ZIV (Zero Index Variable) test is true. */ | |
1480 | ||
1481 | static inline bool | |
ed7a4b4b | 1482 | ziv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1483 | { |
1484 | return (evolution_function_is_constant_p (chrec_a) | |
1485 | && evolution_function_is_constant_p (chrec_b)); | |
1486 | } | |
1487 | ||
1488 | /* Returns true iff CHREC_A and CHREC_B are dependent on an index | |
1489 | variable, i.e., if the SIV (Single Index Variable) test is true. */ | |
1490 | ||
1491 | static bool | |
ed7a4b4b | 1492 | siv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1493 | { |
1494 | if ((evolution_function_is_constant_p (chrec_a) | |
1495 | && evolution_function_is_univariate_p (chrec_b)) | |
1496 | || (evolution_function_is_constant_p (chrec_b) | |
1497 | && evolution_function_is_univariate_p (chrec_a))) | |
1498 | return true; | |
1499 | ||
1500 | if (evolution_function_is_univariate_p (chrec_a) | |
1501 | && evolution_function_is_univariate_p (chrec_b)) | |
1502 | { | |
1503 | switch (TREE_CODE (chrec_a)) | |
1504 | { | |
1505 | case POLYNOMIAL_CHREC: | |
1506 | switch (TREE_CODE (chrec_b)) | |
1507 | { | |
1508 | case POLYNOMIAL_CHREC: | |
1509 | if (CHREC_VARIABLE (chrec_a) != CHREC_VARIABLE (chrec_b)) | |
1510 | return false; | |
1511 | ||
1512 | default: | |
1513 | return true; | |
1514 | } | |
1515 | ||
1516 | default: | |
1517 | return true; | |
1518 | } | |
1519 | } | |
1520 | ||
1521 | return false; | |
1522 | } | |
1523 | ||
d93817c4 ZD |
1524 | /* Creates a conflict function with N dimensions. The affine functions |
1525 | in each dimension follow. */ | |
1526 | ||
1527 | static conflict_function * | |
1528 | conflict_fn (unsigned n, ...) | |
1529 | { | |
1530 | unsigned i; | |
1531 | conflict_function *ret = XCNEW (conflict_function); | |
1532 | va_list ap; | |
1533 | ||
b39c6706 | 1534 | gcc_assert (0 < n && n <= MAX_DIM); |
d93817c4 ZD |
1535 | va_start(ap, n); |
1536 | ||
1537 | ret->n = n; | |
1538 | for (i = 0; i < n; i++) | |
1539 | ret->fns[i] = va_arg (ap, affine_fn); | |
1540 | va_end(ap); | |
1541 | ||
1542 | return ret; | |
1543 | } | |
1544 | ||
1545 | /* Returns constant affine function with value CST. */ | |
1546 | ||
1547 | static affine_fn | |
1548 | affine_fn_cst (tree cst) | |
1549 | { | |
1550 | affine_fn fn = VEC_alloc (tree, heap, 1); | |
1551 | VEC_quick_push (tree, fn, cst); | |
1552 | return fn; | |
1553 | } | |
1554 | ||
1555 | /* Returns affine function with single variable, CST + COEF * x_DIM. */ | |
1556 | ||
1557 | static affine_fn | |
1558 | affine_fn_univar (tree cst, unsigned dim, tree coef) | |
1559 | { | |
1560 | affine_fn fn = VEC_alloc (tree, heap, dim + 1); | |
1561 | unsigned i; | |
1562 | ||
1563 | gcc_assert (dim > 0); | |
1564 | VEC_quick_push (tree, fn, cst); | |
1565 | for (i = 1; i < dim; i++) | |
1566 | VEC_quick_push (tree, fn, integer_zero_node); | |
1567 | VEC_quick_push (tree, fn, coef); | |
1568 | return fn; | |
1569 | } | |
1570 | ||
56cf8686 SP |
1571 | /* Analyze a ZIV (Zero Index Variable) subscript. *OVERLAPS_A and |
1572 | *OVERLAPS_B are initialized to the functions that describe the | |
1573 | relation between the elements accessed twice by CHREC_A and | |
1574 | CHREC_B. For k >= 0, the following property is verified: | |
1575 | ||
1576 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1577 | ||
1578 | static void | |
1579 | analyze_ziv_subscript (tree chrec_a, | |
1580 | tree chrec_b, | |
d93817c4 ZD |
1581 | conflict_function **overlaps_a, |
1582 | conflict_function **overlaps_b, | |
86df10e3 | 1583 | tree *last_conflicts) |
56cf8686 | 1584 | { |
33b30201 | 1585 | tree type, difference; |
0ff4040e | 1586 | dependence_stats.num_ziv++; |
56cf8686 SP |
1587 | |
1588 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1589 | fprintf (dump_file, "(analyze_ziv_subscript \n"); | |
33b30201 SP |
1590 | |
1591 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); | |
726a989a RB |
1592 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1593 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1594 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
56cf8686 SP |
1595 | |
1596 | switch (TREE_CODE (difference)) | |
1597 | { | |
1598 | case INTEGER_CST: | |
1599 | if (integer_zerop (difference)) | |
1600 | { | |
1601 | /* The difference is equal to zero: the accessed index | |
1602 | overlaps for each iteration in the loop. */ | |
d93817c4 ZD |
1603 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
1604 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 | 1605 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1606 | dependence_stats.num_ziv_dependent++; |
56cf8686 SP |
1607 | } |
1608 | else | |
1609 | { | |
1610 | /* The accesses do not overlap. */ | |
d93817c4 ZD |
1611 | *overlaps_a = conflict_fn_no_dependence (); |
1612 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1613 | *last_conflicts = integer_zero_node; |
0ff4040e | 1614 | dependence_stats.num_ziv_independent++; |
56cf8686 SP |
1615 | } |
1616 | break; | |
1617 | ||
1618 | default: | |
1619 | /* We're not sure whether the indexes overlap. For the moment, | |
1620 | conservatively answer "don't know". */ | |
0ff4040e SP |
1621 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1622 | fprintf (dump_file, "ziv test failed: difference is non-integer.\n"); | |
1623 | ||
d93817c4 ZD |
1624 | *overlaps_a = conflict_fn_not_known (); |
1625 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1626 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1627 | dependence_stats.num_ziv_unimplemented++; |
56cf8686 SP |
1628 | break; |
1629 | } | |
1630 | ||
1631 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1632 | fprintf (dump_file, ")\n"); | |
1633 | } | |
1634 | ||
4839cb59 ZD |
1635 | /* Sets NIT to the estimated number of executions of the statements in |
1636 | LOOP. If CONSERVATIVE is true, we must be sure that NIT is at least as | |
1637 | large as the number of iterations. If we have no reliable estimate, | |
1638 | the function returns false, otherwise returns true. */ | |
416f403e | 1639 | |
ac84e05e | 1640 | bool |
4839cb59 ZD |
1641 | estimated_loop_iterations (struct loop *loop, bool conservative, |
1642 | double_int *nit) | |
416f403e | 1643 | { |
9bdb685e ZD |
1644 | estimate_numbers_of_iterations_loop (loop); |
1645 | if (conservative) | |
4839cb59 | 1646 | { |
9bdb685e ZD |
1647 | if (!loop->any_upper_bound) |
1648 | return false; | |
4839cb59 | 1649 | |
9bdb685e | 1650 | *nit = loop->nb_iterations_upper_bound; |
4839cb59 | 1651 | } |
9bdb685e | 1652 | else |
946e1bc7 | 1653 | { |
9bdb685e ZD |
1654 | if (!loop->any_estimate) |
1655 | return false; | |
1656 | ||
1657 | *nit = loop->nb_iterations_estimate; | |
946e1bc7 ZD |
1658 | } |
1659 | ||
9bdb685e | 1660 | return true; |
4839cb59 ZD |
1661 | } |
1662 | ||
1663 | /* Similar to estimated_loop_iterations, but returns the estimate only | |
1664 | if it fits to HOST_WIDE_INT. If this is not the case, or the estimate | |
1665 | on the number of iterations of LOOP could not be derived, returns -1. */ | |
1666 | ||
1667 | HOST_WIDE_INT | |
1668 | estimated_loop_iterations_int (struct loop *loop, bool conservative) | |
1669 | { | |
1670 | double_int nit; | |
1671 | HOST_WIDE_INT hwi_nit; | |
1672 | ||
1673 | if (!estimated_loop_iterations (loop, conservative, &nit)) | |
1674 | return -1; | |
1675 | ||
1676 | if (!double_int_fits_in_shwi_p (nit)) | |
1677 | return -1; | |
1678 | hwi_nit = double_int_to_shwi (nit); | |
1679 | ||
1680 | return hwi_nit < 0 ? -1 : hwi_nit; | |
416f403e DB |
1681 | } |
1682 | ||
4839cb59 ZD |
1683 | /* Similar to estimated_loop_iterations, but returns the estimate as a tree, |
1684 | and only if it fits to the int type. If this is not the case, or the | |
1685 | estimate on the number of iterations of LOOP could not be derived, returns | |
1686 | chrec_dont_know. */ | |
1687 | ||
1688 | static tree | |
1689 | estimated_loop_iterations_tree (struct loop *loop, bool conservative) | |
1690 | { | |
1691 | double_int nit; | |
1692 | tree type; | |
1693 | ||
1694 | if (!estimated_loop_iterations (loop, conservative, &nit)) | |
1695 | return chrec_dont_know; | |
1696 | ||
1697 | type = lang_hooks.types.type_for_size (INT_TYPE_SIZE, true); | |
1698 | if (!double_int_fits_to_tree_p (type, nit)) | |
1699 | return chrec_dont_know; | |
1700 | ||
1701 | return double_int_to_tree (type, nit); | |
1702 | } | |
1703 | ||
56cf8686 SP |
1704 | /* Analyze a SIV (Single Index Variable) subscript where CHREC_A is a |
1705 | constant, and CHREC_B is an affine function. *OVERLAPS_A and | |
1706 | *OVERLAPS_B are initialized to the functions that describe the | |
1707 | relation between the elements accessed twice by CHREC_A and | |
1708 | CHREC_B. For k >= 0, the following property is verified: | |
1709 | ||
1710 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1711 | ||
1712 | static void | |
1713 | analyze_siv_subscript_cst_affine (tree chrec_a, | |
1714 | tree chrec_b, | |
d93817c4 ZD |
1715 | conflict_function **overlaps_a, |
1716 | conflict_function **overlaps_b, | |
86df10e3 | 1717 | tree *last_conflicts) |
56cf8686 SP |
1718 | { |
1719 | bool value0, value1, value2; | |
33b30201 | 1720 | tree type, difference, tmp; |
e2157b49 | 1721 | |
33b30201 | 1722 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
1723 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1724 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1725 | difference = chrec_fold_minus (type, initial_condition (chrec_b), chrec_a); |
56cf8686 SP |
1726 | |
1727 | if (!chrec_is_positive (initial_condition (difference), &value0)) | |
1728 | { | |
0ff4040e SP |
1729 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1730 | fprintf (dump_file, "siv test failed: chrec is not positive.\n"); | |
1731 | ||
1732 | dependence_stats.num_siv_unimplemented++; | |
d93817c4 ZD |
1733 | *overlaps_a = conflict_fn_not_known (); |
1734 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1735 | *last_conflicts = chrec_dont_know; |
56cf8686 SP |
1736 | return; |
1737 | } | |
1738 | else | |
1739 | { | |
1740 | if (value0 == false) | |
1741 | { | |
1742 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value1)) | |
1743 | { | |
0ff4040e SP |
1744 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1745 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1746 | ||
d93817c4 ZD |
1747 | *overlaps_a = conflict_fn_not_known (); |
1748 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1749 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1750 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1751 | return; |
1752 | } | |
1753 | else | |
1754 | { | |
1755 | if (value1 == true) | |
1756 | { | |
1757 | /* Example: | |
1758 | chrec_a = 12 | |
1759 | chrec_b = {10, +, 1} | |
1760 | */ | |
1761 | ||
f457cf40 | 1762 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1763 | { |
4839cb59 ZD |
1764 | HOST_WIDE_INT numiter; |
1765 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1766 | |
d93817c4 | 1767 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 SP |
1768 | tmp = fold_build2 (EXACT_DIV_EXPR, type, |
1769 | fold_build1 (ABS_EXPR, type, difference), | |
d93817c4 ZD |
1770 | CHREC_RIGHT (chrec_b)); |
1771 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1772 | *last_conflicts = integer_one_node; |
416f403e DB |
1773 | |
1774 | ||
1775 | /* Perform weak-zero siv test to see if overlap is | |
1776 | outside the loop bounds. */ | |
fd727b34 | 1777 | numiter = estimated_loop_iterations_int (loop, false); |
416f403e | 1778 | |
4839cb59 ZD |
1779 | if (numiter >= 0 |
1780 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 1781 | { |
d93817c4 ZD |
1782 | free_conflict_function (*overlaps_a); |
1783 | free_conflict_function (*overlaps_b); | |
1784 | *overlaps_a = conflict_fn_no_dependence (); | |
1785 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 1786 | *last_conflicts = integer_zero_node; |
0ff4040e | 1787 | dependence_stats.num_siv_independent++; |
416f403e DB |
1788 | return; |
1789 | } | |
0ff4040e | 1790 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
1791 | return; |
1792 | } | |
1793 | ||
f457cf40 | 1794 | /* When the step does not divide the difference, there are |
56cf8686 SP |
1795 | no overlaps. */ |
1796 | else | |
1797 | { | |
d93817c4 ZD |
1798 | *overlaps_a = conflict_fn_no_dependence (); |
1799 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1800 | *last_conflicts = integer_zero_node; |
0ff4040e | 1801 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1802 | return; |
1803 | } | |
1804 | } | |
1805 | ||
1806 | else | |
1807 | { | |
1808 | /* Example: | |
1809 | chrec_a = 12 | |
1810 | chrec_b = {10, +, -1} | |
1811 | ||
1812 | In this case, chrec_a will not overlap with chrec_b. */ | |
d93817c4 ZD |
1813 | *overlaps_a = conflict_fn_no_dependence (); |
1814 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1815 | *last_conflicts = integer_zero_node; |
0ff4040e | 1816 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1817 | return; |
1818 | } | |
1819 | } | |
1820 | } | |
1821 | else | |
1822 | { | |
1823 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value2)) | |
1824 | { | |
0ff4040e SP |
1825 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1826 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1827 | ||
d93817c4 ZD |
1828 | *overlaps_a = conflict_fn_not_known (); |
1829 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1830 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1831 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1832 | return; |
1833 | } | |
1834 | else | |
1835 | { | |
1836 | if (value2 == false) | |
1837 | { | |
1838 | /* Example: | |
1839 | chrec_a = 3 | |
1840 | chrec_b = {10, +, -1} | |
1841 | */ | |
f457cf40 | 1842 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1843 | { |
4839cb59 ZD |
1844 | HOST_WIDE_INT numiter; |
1845 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1846 | |
d93817c4 | 1847 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 | 1848 | tmp = fold_build2 (EXACT_DIV_EXPR, type, difference, |
d93817c4 ZD |
1849 | CHREC_RIGHT (chrec_b)); |
1850 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1851 | *last_conflicts = integer_one_node; |
416f403e DB |
1852 | |
1853 | /* Perform weak-zero siv test to see if overlap is | |
1854 | outside the loop bounds. */ | |
fd727b34 | 1855 | numiter = estimated_loop_iterations_int (loop, false); |
416f403e | 1856 | |
4839cb59 ZD |
1857 | if (numiter >= 0 |
1858 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 1859 | { |
d93817c4 ZD |
1860 | free_conflict_function (*overlaps_a); |
1861 | free_conflict_function (*overlaps_b); | |
1862 | *overlaps_a = conflict_fn_no_dependence (); | |
1863 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 1864 | *last_conflicts = integer_zero_node; |
0ff4040e | 1865 | dependence_stats.num_siv_independent++; |
416f403e DB |
1866 | return; |
1867 | } | |
0ff4040e | 1868 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
1869 | return; |
1870 | } | |
1871 | ||
4286d8ce | 1872 | /* When the step does not divide the difference, there |
56cf8686 SP |
1873 | are no overlaps. */ |
1874 | else | |
1875 | { | |
d93817c4 ZD |
1876 | *overlaps_a = conflict_fn_no_dependence (); |
1877 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1878 | *last_conflicts = integer_zero_node; |
0ff4040e | 1879 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1880 | return; |
1881 | } | |
1882 | } | |
1883 | else | |
1884 | { | |
1885 | /* Example: | |
1886 | chrec_a = 3 | |
1887 | chrec_b = {4, +, 1} | |
1888 | ||
1889 | In this case, chrec_a will not overlap with chrec_b. */ | |
d93817c4 ZD |
1890 | *overlaps_a = conflict_fn_no_dependence (); |
1891 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1892 | *last_conflicts = integer_zero_node; |
0ff4040e | 1893 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1894 | return; |
1895 | } | |
1896 | } | |
1897 | } | |
1898 | } | |
1899 | } | |
1900 | ||
50300b4c | 1901 | /* Helper recursive function for initializing the matrix A. Returns |
86df10e3 | 1902 | the initial value of CHREC. */ |
56cf8686 | 1903 | |
5b78fc3e | 1904 | static tree |
86df10e3 SP |
1905 | initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) |
1906 | { | |
1907 | gcc_assert (chrec); | |
1908 | ||
5b78fc3e JS |
1909 | switch (TREE_CODE (chrec)) |
1910 | { | |
1911 | case POLYNOMIAL_CHREC: | |
1912 | gcc_assert (TREE_CODE (CHREC_RIGHT (chrec)) == INTEGER_CST); | |
1913 | ||
1914 | A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); | |
1915 | return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); | |
1916 | ||
1917 | case PLUS_EXPR: | |
1918 | case MULT_EXPR: | |
1919 | case MINUS_EXPR: | |
1920 | { | |
1921 | tree op0 = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
1922 | tree op1 = initialize_matrix_A (A, TREE_OPERAND (chrec, 1), index, mult); | |
1923 | ||
1924 | return chrec_fold_op (TREE_CODE (chrec), chrec_type (chrec), op0, op1); | |
1925 | } | |
1926 | ||
1927 | case NOP_EXPR: | |
1928 | { | |
1929 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
726a989a | 1930 | return chrec_convert (chrec_type (chrec), op, NULL); |
5b78fc3e JS |
1931 | } |
1932 | ||
418df9d7 JJ |
1933 | case BIT_NOT_EXPR: |
1934 | { | |
1935 | /* Handle ~X as -1 - X. */ | |
1936 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
1937 | return chrec_fold_op (MINUS_EXPR, chrec_type (chrec), | |
1938 | build_int_cst (TREE_TYPE (chrec), -1), op); | |
1939 | } | |
1940 | ||
5b78fc3e JS |
1941 | case INTEGER_CST: |
1942 | return chrec; | |
a1a5996d | 1943 | |
5b78fc3e JS |
1944 | default: |
1945 | gcc_unreachable (); | |
1946 | return NULL_TREE; | |
1947 | } | |
86df10e3 SP |
1948 | } |
1949 | ||
1950 | #define FLOOR_DIV(x,y) ((x) / (y)) | |
1951 | ||
1952 | /* Solves the special case of the Diophantine equation: | |
1953 | | {0, +, STEP_A}_x (OVERLAPS_A) = {0, +, STEP_B}_y (OVERLAPS_B) | |
1954 | ||
1955 | Computes the descriptions OVERLAPS_A and OVERLAPS_B. NITER is the | |
1956 | number of iterations that loops X and Y run. The overlaps will be | |
1957 | constructed as evolutions in dimension DIM. */ | |
56cf8686 SP |
1958 | |
1959 | static void | |
86df10e3 | 1960 | compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b, |
d93817c4 ZD |
1961 | affine_fn *overlaps_a, |
1962 | affine_fn *overlaps_b, | |
86df10e3 SP |
1963 | tree *last_conflicts, int dim) |
1964 | { | |
1965 | if (((step_a > 0 && step_b > 0) | |
1966 | || (step_a < 0 && step_b < 0))) | |
1967 | { | |
1968 | int step_overlaps_a, step_overlaps_b; | |
1969 | int gcd_steps_a_b, last_conflict, tau2; | |
1970 | ||
1971 | gcd_steps_a_b = gcd (step_a, step_b); | |
1972 | step_overlaps_a = step_b / gcd_steps_a_b; | |
1973 | step_overlaps_b = step_a / gcd_steps_a_b; | |
1974 | ||
2c26cbfd SP |
1975 | if (niter > 0) |
1976 | { | |
1977 | tau2 = FLOOR_DIV (niter, step_overlaps_a); | |
1978 | tau2 = MIN (tau2, FLOOR_DIV (niter, step_overlaps_b)); | |
1979 | last_conflict = tau2; | |
1980 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); | |
1981 | } | |
1982 | else | |
1983 | *last_conflicts = chrec_dont_know; | |
86df10e3 | 1984 | |
d93817c4 ZD |
1985 | *overlaps_a = affine_fn_univar (integer_zero_node, dim, |
1986 | build_int_cst (NULL_TREE, | |
1987 | step_overlaps_a)); | |
1988 | *overlaps_b = affine_fn_univar (integer_zero_node, dim, | |
1989 | build_int_cst (NULL_TREE, | |
1990 | step_overlaps_b)); | |
86df10e3 SP |
1991 | } |
1992 | ||
1993 | else | |
1994 | { | |
d93817c4 ZD |
1995 | *overlaps_a = affine_fn_cst (integer_zero_node); |
1996 | *overlaps_b = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
1997 | *last_conflicts = integer_zero_node; |
1998 | } | |
1999 | } | |
2000 | ||
86df10e3 SP |
2001 | /* Solves the special case of a Diophantine equation where CHREC_A is |
2002 | an affine bivariate function, and CHREC_B is an affine univariate | |
2003 | function. For example, | |
2004 | ||
2005 | | {{0, +, 1}_x, +, 1335}_y = {0, +, 1336}_z | |
2006 | ||
2007 | has the following overlapping functions: | |
2008 | ||
2009 | | x (t, u, v) = {{0, +, 1336}_t, +, 1}_v | |
2010 | | y (t, u, v) = {{0, +, 1336}_u, +, 1}_v | |
2011 | | z (t, u, v) = {{{0, +, 1}_t, +, 1335}_u, +, 1}_v | |
2012 | ||
35fd3193 | 2013 | FORNOW: This is a specialized implementation for a case occurring in |
86df10e3 SP |
2014 | a common benchmark. Implement the general algorithm. */ |
2015 | ||
2016 | static void | |
2017 | compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b, | |
d93817c4 ZD |
2018 | conflict_function **overlaps_a, |
2019 | conflict_function **overlaps_b, | |
86df10e3 | 2020 | tree *last_conflicts) |
56cf8686 | 2021 | { |
86df10e3 SP |
2022 | bool xz_p, yz_p, xyz_p; |
2023 | int step_x, step_y, step_z; | |
4839cb59 | 2024 | HOST_WIDE_INT niter_x, niter_y, niter_z, niter; |
d93817c4 ZD |
2025 | affine_fn overlaps_a_xz, overlaps_b_xz; |
2026 | affine_fn overlaps_a_yz, overlaps_b_yz; | |
2027 | affine_fn overlaps_a_xyz, overlaps_b_xyz; | |
2028 | affine_fn ova1, ova2, ovb; | |
2029 | tree last_conflicts_xz, last_conflicts_yz, last_conflicts_xyz; | |
86df10e3 | 2030 | |
6b6fa4e9 SP |
2031 | step_x = int_cst_value (CHREC_RIGHT (CHREC_LEFT (chrec_a))); |
2032 | step_y = int_cst_value (CHREC_RIGHT (chrec_a)); | |
2033 | step_z = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2034 | |
fd727b34 SP |
2035 | niter_x = |
2036 | estimated_loop_iterations_int (get_chrec_loop (CHREC_LEFT (chrec_a)), | |
2037 | false); | |
2038 | niter_y = estimated_loop_iterations_int (get_chrec_loop (chrec_a), false); | |
2039 | niter_z = estimated_loop_iterations_int (get_chrec_loop (chrec_b), false); | |
416f403e | 2040 | |
4839cb59 | 2041 | if (niter_x < 0 || niter_y < 0 || niter_z < 0) |
86df10e3 | 2042 | { |
0ff4040e SP |
2043 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2044 | fprintf (dump_file, "overlap steps test failed: no iteration counts.\n"); | |
2045 | ||
d93817c4 ZD |
2046 | *overlaps_a = conflict_fn_not_known (); |
2047 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2048 | *last_conflicts = chrec_dont_know; |
2049 | return; | |
2050 | } | |
2051 | ||
86df10e3 SP |
2052 | niter = MIN (niter_x, niter_z); |
2053 | compute_overlap_steps_for_affine_univar (niter, step_x, step_z, | |
2054 | &overlaps_a_xz, | |
2055 | &overlaps_b_xz, | |
2056 | &last_conflicts_xz, 1); | |
2057 | niter = MIN (niter_y, niter_z); | |
2058 | compute_overlap_steps_for_affine_univar (niter, step_y, step_z, | |
2059 | &overlaps_a_yz, | |
2060 | &overlaps_b_yz, | |
2061 | &last_conflicts_yz, 2); | |
2062 | niter = MIN (niter_x, niter_z); | |
2063 | niter = MIN (niter_y, niter); | |
2064 | compute_overlap_steps_for_affine_univar (niter, step_x + step_y, step_z, | |
2065 | &overlaps_a_xyz, | |
2066 | &overlaps_b_xyz, | |
2067 | &last_conflicts_xyz, 3); | |
2068 | ||
2069 | xz_p = !integer_zerop (last_conflicts_xz); | |
2070 | yz_p = !integer_zerop (last_conflicts_yz); | |
2071 | xyz_p = !integer_zerop (last_conflicts_xyz); | |
2072 | ||
2073 | if (xz_p || yz_p || xyz_p) | |
2074 | { | |
d93817c4 ZD |
2075 | ova1 = affine_fn_cst (integer_zero_node); |
2076 | ova2 = affine_fn_cst (integer_zero_node); | |
2077 | ovb = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
2078 | if (xz_p) |
2079 | { | |
d93817c4 ZD |
2080 | affine_fn t0 = ova1; |
2081 | affine_fn t2 = ovb; | |
2082 | ||
2083 | ova1 = affine_fn_plus (ova1, overlaps_a_xz); | |
2084 | ovb = affine_fn_plus (ovb, overlaps_b_xz); | |
2085 | affine_fn_free (t0); | |
2086 | affine_fn_free (t2); | |
86df10e3 SP |
2087 | *last_conflicts = last_conflicts_xz; |
2088 | } | |
2089 | if (yz_p) | |
2090 | { | |
d93817c4 ZD |
2091 | affine_fn t0 = ova2; |
2092 | affine_fn t2 = ovb; | |
2093 | ||
2094 | ova2 = affine_fn_plus (ova2, overlaps_a_yz); | |
2095 | ovb = affine_fn_plus (ovb, overlaps_b_yz); | |
2096 | affine_fn_free (t0); | |
2097 | affine_fn_free (t2); | |
86df10e3 SP |
2098 | *last_conflicts = last_conflicts_yz; |
2099 | } | |
2100 | if (xyz_p) | |
2101 | { | |
d93817c4 ZD |
2102 | affine_fn t0 = ova1; |
2103 | affine_fn t2 = ova2; | |
2104 | affine_fn t4 = ovb; | |
2105 | ||
2106 | ova1 = affine_fn_plus (ova1, overlaps_a_xyz); | |
2107 | ova2 = affine_fn_plus (ova2, overlaps_a_xyz); | |
2108 | ovb = affine_fn_plus (ovb, overlaps_b_xyz); | |
2109 | affine_fn_free (t0); | |
2110 | affine_fn_free (t2); | |
2111 | affine_fn_free (t4); | |
86df10e3 SP |
2112 | *last_conflicts = last_conflicts_xyz; |
2113 | } | |
d93817c4 ZD |
2114 | *overlaps_a = conflict_fn (2, ova1, ova2); |
2115 | *overlaps_b = conflict_fn (1, ovb); | |
86df10e3 SP |
2116 | } |
2117 | else | |
2118 | { | |
d93817c4 ZD |
2119 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2120 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 SP |
2121 | *last_conflicts = integer_zero_node; |
2122 | } | |
d93817c4 ZD |
2123 | |
2124 | affine_fn_free (overlaps_a_xz); | |
2125 | affine_fn_free (overlaps_b_xz); | |
2126 | affine_fn_free (overlaps_a_yz); | |
2127 | affine_fn_free (overlaps_b_yz); | |
2128 | affine_fn_free (overlaps_a_xyz); | |
2129 | affine_fn_free (overlaps_b_xyz); | |
56cf8686 SP |
2130 | } |
2131 | ||
2132 | /* Determines the overlapping elements due to accesses CHREC_A and | |
0ff4040e SP |
2133 | CHREC_B, that are affine functions. This function cannot handle |
2134 | symbolic evolution functions, ie. when initial conditions are | |
2135 | parameters, because it uses lambda matrices of integers. */ | |
56cf8686 SP |
2136 | |
2137 | static void | |
2138 | analyze_subscript_affine_affine (tree chrec_a, | |
2139 | tree chrec_b, | |
d93817c4 ZD |
2140 | conflict_function **overlaps_a, |
2141 | conflict_function **overlaps_b, | |
86df10e3 | 2142 | tree *last_conflicts) |
56cf8686 | 2143 | { |
86df10e3 | 2144 | unsigned nb_vars_a, nb_vars_b, dim; |
fd727b34 | 2145 | HOST_WIDE_INT init_a, init_b, gamma, gcd_alpha_beta; |
86df10e3 SP |
2146 | lambda_matrix A, U, S; |
2147 | ||
e2157b49 | 2148 | if (eq_evolutions_p (chrec_a, chrec_b)) |
416f403e | 2149 | { |
e2157b49 SP |
2150 | /* The accessed index overlaps for each iteration in the |
2151 | loop. */ | |
d93817c4 ZD |
2152 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2153 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
416f403e DB |
2154 | *last_conflicts = chrec_dont_know; |
2155 | return; | |
2156 | } | |
56cf8686 SP |
2157 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2158 | fprintf (dump_file, "(analyze_subscript_affine_affine \n"); | |
2159 | ||
2160 | /* For determining the initial intersection, we have to solve a | |
2161 | Diophantine equation. This is the most time consuming part. | |
2162 | ||
2163 | For answering to the question: "Is there a dependence?" we have | |
2164 | to prove that there exists a solution to the Diophantine | |
2165 | equation, and that the solution is in the iteration domain, | |
89dbed81 | 2166 | i.e. the solution is positive or zero, and that the solution |
56cf8686 SP |
2167 | happens before the upper bound loop.nb_iterations. Otherwise |
2168 | there is no dependence. This function outputs a description of | |
2169 | the iterations that hold the intersections. */ | |
2170 | ||
86df10e3 SP |
2171 | nb_vars_a = nb_vars_in_chrec (chrec_a); |
2172 | nb_vars_b = nb_vars_in_chrec (chrec_b); | |
2173 | ||
2174 | dim = nb_vars_a + nb_vars_b; | |
2175 | U = lambda_matrix_new (dim, dim); | |
2176 | A = lambda_matrix_new (dim, 1); | |
2177 | S = lambda_matrix_new (dim, 1); | |
2178 | ||
5b78fc3e JS |
2179 | init_a = int_cst_value (initialize_matrix_A (A, chrec_a, 0, 1)); |
2180 | init_b = int_cst_value (initialize_matrix_A (A, chrec_b, nb_vars_a, -1)); | |
86df10e3 SP |
2181 | gamma = init_b - init_a; |
2182 | ||
2183 | /* Don't do all the hard work of solving the Diophantine equation | |
2184 | when we already know the solution: for example, | |
2185 | | {3, +, 1}_1 | |
2186 | | {3, +, 4}_2 | |
2187 | | gamma = 3 - 3 = 0. | |
2188 | Then the first overlap occurs during the first iterations: | |
2189 | | {3, +, 1}_1 ({0, +, 4}_x) = {3, +, 4}_2 ({0, +, 1}_x) | |
2190 | */ | |
2191 | if (gamma == 0) | |
56cf8686 | 2192 | { |
86df10e3 | 2193 | if (nb_vars_a == 1 && nb_vars_b == 1) |
56cf8686 | 2194 | { |
fd727b34 | 2195 | HOST_WIDE_INT step_a, step_b; |
4839cb59 | 2196 | HOST_WIDE_INT niter, niter_a, niter_b; |
d93817c4 | 2197 | affine_fn ova, ovb; |
86df10e3 | 2198 | |
fd727b34 SP |
2199 | niter_a = estimated_loop_iterations_int (get_chrec_loop (chrec_a), |
2200 | false); | |
2201 | niter_b = estimated_loop_iterations_int (get_chrec_loop (chrec_b), | |
2202 | false); | |
86df10e3 | 2203 | niter = MIN (niter_a, niter_b); |
6b6fa4e9 SP |
2204 | step_a = int_cst_value (CHREC_RIGHT (chrec_a)); |
2205 | step_b = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 SP |
2206 | |
2207 | compute_overlap_steps_for_affine_univar (niter, step_a, step_b, | |
d93817c4 | 2208 | &ova, &ovb, |
86df10e3 | 2209 | last_conflicts, 1); |
d93817c4 ZD |
2210 | *overlaps_a = conflict_fn (1, ova); |
2211 | *overlaps_b = conflict_fn (1, ovb); | |
56cf8686 | 2212 | } |
86df10e3 SP |
2213 | |
2214 | else if (nb_vars_a == 2 && nb_vars_b == 1) | |
2215 | compute_overlap_steps_for_affine_1_2 | |
2216 | (chrec_a, chrec_b, overlaps_a, overlaps_b, last_conflicts); | |
2217 | ||
2218 | else if (nb_vars_a == 1 && nb_vars_b == 2) | |
2219 | compute_overlap_steps_for_affine_1_2 | |
2220 | (chrec_b, chrec_a, overlaps_b, overlaps_a, last_conflicts); | |
2221 | ||
2222 | else | |
56cf8686 | 2223 | { |
0ff4040e SP |
2224 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2225 | fprintf (dump_file, "affine-affine test failed: too many variables.\n"); | |
d93817c4 ZD |
2226 | *overlaps_a = conflict_fn_not_known (); |
2227 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2228 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2229 | } |
0ff4040e | 2230 | goto end_analyze_subs_aa; |
86df10e3 SP |
2231 | } |
2232 | ||
2233 | /* U.A = S */ | |
2234 | lambda_matrix_right_hermite (A, dim, 1, S, U); | |
2235 | ||
2236 | if (S[0][0] < 0) | |
2237 | { | |
2238 | S[0][0] *= -1; | |
2239 | lambda_matrix_row_negate (U, dim, 0); | |
2240 | } | |
2241 | gcd_alpha_beta = S[0][0]; | |
2242 | ||
ba42e045 SP |
2243 | /* Something went wrong: for example in {1, +, 0}_5 vs. {0, +, 0}_5, |
2244 | but that is a quite strange case. Instead of ICEing, answer | |
2245 | don't know. */ | |
2246 | if (gcd_alpha_beta == 0) | |
2247 | { | |
d93817c4 ZD |
2248 | *overlaps_a = conflict_fn_not_known (); |
2249 | *overlaps_b = conflict_fn_not_known (); | |
ba42e045 SP |
2250 | *last_conflicts = chrec_dont_know; |
2251 | goto end_analyze_subs_aa; | |
2252 | } | |
2253 | ||
86df10e3 SP |
2254 | /* The classic "gcd-test". */ |
2255 | if (!int_divides_p (gcd_alpha_beta, gamma)) | |
2256 | { | |
2257 | /* The "gcd-test" has determined that there is no integer | |
2258 | solution, i.e. there is no dependence. */ | |
d93817c4 ZD |
2259 | *overlaps_a = conflict_fn_no_dependence (); |
2260 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 SP |
2261 | *last_conflicts = integer_zero_node; |
2262 | } | |
2263 | ||
2264 | /* Both access functions are univariate. This includes SIV and MIV cases. */ | |
2265 | else if (nb_vars_a == 1 && nb_vars_b == 1) | |
2266 | { | |
2267 | /* Both functions should have the same evolution sign. */ | |
2268 | if (((A[0][0] > 0 && -A[1][0] > 0) | |
2269 | || (A[0][0] < 0 && -A[1][0] < 0))) | |
56cf8686 SP |
2270 | { |
2271 | /* The solutions are given by: | |
2272 | | | |
86df10e3 SP |
2273 | | [GAMMA/GCD_ALPHA_BETA t].[u11 u12] = [x0] |
2274 | | [u21 u22] [y0] | |
2275 | ||
56cf8686 | 2276 | For a given integer t. Using the following variables, |
86df10e3 | 2277 | |
56cf8686 SP |
2278 | | i0 = u11 * gamma / gcd_alpha_beta |
2279 | | j0 = u12 * gamma / gcd_alpha_beta | |
2280 | | i1 = u21 | |
2281 | | j1 = u22 | |
86df10e3 | 2282 | |
56cf8686 | 2283 | the solutions are: |
86df10e3 SP |
2284 | |
2285 | | x0 = i0 + i1 * t, | |
2286 | | y0 = j0 + j1 * t. */ | |
2c26cbfd | 2287 | HOST_WIDE_INT i0, j0, i1, j1; |
86df10e3 SP |
2288 | |
2289 | i0 = U[0][0] * gamma / gcd_alpha_beta; | |
2290 | j0 = U[0][1] * gamma / gcd_alpha_beta; | |
2291 | i1 = U[1][0]; | |
2292 | j1 = U[1][1]; | |
2293 | ||
2294 | if ((i1 == 0 && i0 < 0) | |
2295 | || (j1 == 0 && j0 < 0)) | |
56cf8686 SP |
2296 | { |
2297 | /* There is no solution. | |
2298 | FIXME: The case "i0 > nb_iterations, j0 > nb_iterations" | |
2299 | falls in here, but for the moment we don't look at the | |
2300 | upper bound of the iteration domain. */ | |
d93817c4 ZD |
2301 | *overlaps_a = conflict_fn_no_dependence (); |
2302 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2303 | *last_conflicts = integer_zero_node; |
2c26cbfd | 2304 | goto end_analyze_subs_aa; |
86df10e3 SP |
2305 | } |
2306 | ||
2c26cbfd | 2307 | if (i1 > 0 && j1 > 0) |
56cf8686 | 2308 | { |
2c26cbfd SP |
2309 | HOST_WIDE_INT niter_a = estimated_loop_iterations_int |
2310 | (get_chrec_loop (chrec_a), false); | |
2311 | HOST_WIDE_INT niter_b = estimated_loop_iterations_int | |
2312 | (get_chrec_loop (chrec_b), false); | |
2313 | HOST_WIDE_INT niter = MIN (niter_a, niter_b); | |
2314 | ||
2315 | /* (X0, Y0) is a solution of the Diophantine equation: | |
2316 | "chrec_a (X0) = chrec_b (Y0)". */ | |
2317 | HOST_WIDE_INT tau1 = MAX (CEIL (-i0, i1), | |
2318 | CEIL (-j0, j1)); | |
2319 | HOST_WIDE_INT x0 = i1 * tau1 + i0; | |
2320 | HOST_WIDE_INT y0 = j1 * tau1 + j0; | |
2321 | ||
2322 | /* (X1, Y1) is the smallest positive solution of the eq | |
2323 | "chrec_a (X1) = chrec_b (Y1)", i.e. this is where the | |
2324 | first conflict occurs. */ | |
2325 | HOST_WIDE_INT min_multiple = MIN (x0 / i1, y0 / j1); | |
2326 | HOST_WIDE_INT x1 = x0 - i1 * min_multiple; | |
2327 | HOST_WIDE_INT y1 = y0 - j1 * min_multiple; | |
2328 | ||
2329 | if (niter > 0) | |
56cf8686 | 2330 | { |
2c26cbfd SP |
2331 | HOST_WIDE_INT tau2 = MIN (FLOOR_DIV (niter - i0, i1), |
2332 | FLOOR_DIV (niter - j0, j1)); | |
2333 | HOST_WIDE_INT last_conflict = tau2 - (x1 - i0)/i1; | |
86df10e3 | 2334 | |
2c26cbfd SP |
2335 | /* If the overlap occurs outside of the bounds of the |
2336 | loop, there is no dependence. */ | |
9e517d61 | 2337 | if (x1 >= niter || y1 >= niter) |
56cf8686 | 2338 | { |
2c26cbfd SP |
2339 | *overlaps_a = conflict_fn_no_dependence (); |
2340 | *overlaps_b = conflict_fn_no_dependence (); | |
2341 | *last_conflicts = integer_zero_node; | |
2342 | goto end_analyze_subs_aa; | |
56cf8686 SP |
2343 | } |
2344 | else | |
2c26cbfd | 2345 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); |
56cf8686 | 2346 | } |
56cf8686 | 2347 | else |
2c26cbfd SP |
2348 | *last_conflicts = chrec_dont_know; |
2349 | ||
2350 | *overlaps_a | |
2351 | = conflict_fn (1, | |
2352 | affine_fn_univar (build_int_cst (NULL_TREE, x1), | |
2353 | 1, | |
2354 | build_int_cst (NULL_TREE, i1))); | |
2355 | *overlaps_b | |
2356 | = conflict_fn (1, | |
2357 | affine_fn_univar (build_int_cst (NULL_TREE, y1), | |
2358 | 1, | |
2359 | build_int_cst (NULL_TREE, j1))); | |
2360 | } | |
2361 | else | |
2362 | { | |
2363 | /* FIXME: For the moment, the upper bound of the | |
2364 | iteration domain for i and j is not checked. */ | |
2365 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2366 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
2367 | *overlaps_a = conflict_fn_not_known (); | |
2368 | *overlaps_b = conflict_fn_not_known (); | |
2369 | *last_conflicts = chrec_dont_know; | |
56cf8686 SP |
2370 | } |
2371 | } | |
86df10e3 SP |
2372 | else |
2373 | { | |
0ff4040e SP |
2374 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2375 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2376 | *overlaps_a = conflict_fn_not_known (); |
2377 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2378 | *last_conflicts = chrec_dont_know; |
2379 | } | |
56cf8686 | 2380 | } |
56cf8686 SP |
2381 | else |
2382 | { | |
0ff4040e SP |
2383 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2384 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2385 | *overlaps_a = conflict_fn_not_known (); |
2386 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2387 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2388 | } |
86df10e3 | 2389 | |
0ff4040e | 2390 | end_analyze_subs_aa: |
56cf8686 SP |
2391 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2392 | { | |
2393 | fprintf (dump_file, " (overlaps_a = "); | |
d93817c4 | 2394 | dump_conflict_function (dump_file, *overlaps_a); |
56cf8686 | 2395 | fprintf (dump_file, ")\n (overlaps_b = "); |
d93817c4 | 2396 | dump_conflict_function (dump_file, *overlaps_b); |
56cf8686 | 2397 | fprintf (dump_file, ")\n"); |
0ff4040e | 2398 | fprintf (dump_file, ")\n"); |
56cf8686 | 2399 | } |
0ff4040e SP |
2400 | } |
2401 | ||
2402 | /* Returns true when analyze_subscript_affine_affine can be used for | |
2403 | determining the dependence relation between chrec_a and chrec_b, | |
2404 | that contain symbols. This function modifies chrec_a and chrec_b | |
2405 | such that the analysis result is the same, and such that they don't | |
2406 | contain symbols, and then can safely be passed to the analyzer. | |
2407 | ||
2408 | Example: The analysis of the following tuples of evolutions produce | |
2409 | the same results: {x+1, +, 1}_1 vs. {x+3, +, 1}_1, and {-2, +, 1}_1 | |
2410 | vs. {0, +, 1}_1 | |
2411 | ||
2412 | {x+1, +, 1}_1 ({2, +, 1}_1) = {x+3, +, 1}_1 ({0, +, 1}_1) | |
2413 | {-2, +, 1}_1 ({2, +, 1}_1) = {0, +, 1}_1 ({0, +, 1}_1) | |
2414 | */ | |
2415 | ||
2416 | static bool | |
2417 | can_use_analyze_subscript_affine_affine (tree *chrec_a, tree *chrec_b) | |
2418 | { | |
16a2acea | 2419 | tree diff, type, left_a, left_b, right_b; |
0ff4040e SP |
2420 | |
2421 | if (chrec_contains_symbols (CHREC_RIGHT (*chrec_a)) | |
2422 | || chrec_contains_symbols (CHREC_RIGHT (*chrec_b))) | |
2423 | /* FIXME: For the moment not handled. Might be refined later. */ | |
2424 | return false; | |
2425 | ||
16a2acea SP |
2426 | type = chrec_type (*chrec_a); |
2427 | left_a = CHREC_LEFT (*chrec_a); | |
726a989a | 2428 | left_b = chrec_convert (type, CHREC_LEFT (*chrec_b), NULL); |
16a2acea SP |
2429 | diff = chrec_fold_minus (type, left_a, left_b); |
2430 | ||
0ff4040e SP |
2431 | if (!evolution_function_is_constant_p (diff)) |
2432 | return false; | |
2433 | ||
56cf8686 | 2434 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e SP |
2435 | fprintf (dump_file, "can_use_subscript_aff_aff_for_symbolic \n"); |
2436 | ||
2437 | *chrec_a = build_polynomial_chrec (CHREC_VARIABLE (*chrec_a), | |
2438 | diff, CHREC_RIGHT (*chrec_a)); | |
726a989a | 2439 | right_b = chrec_convert (type, CHREC_RIGHT (*chrec_b), NULL); |
0ff4040e | 2440 | *chrec_b = build_polynomial_chrec (CHREC_VARIABLE (*chrec_b), |
dc61cc6b | 2441 | build_int_cst (type, 0), |
16a2acea | 2442 | right_b); |
0ff4040e | 2443 | return true; |
56cf8686 SP |
2444 | } |
2445 | ||
2446 | /* Analyze a SIV (Single Index Variable) subscript. *OVERLAPS_A and | |
2447 | *OVERLAPS_B are initialized to the functions that describe the | |
2448 | relation between the elements accessed twice by CHREC_A and | |
2449 | CHREC_B. For k >= 0, the following property is verified: | |
2450 | ||
2451 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2452 | ||
2453 | static void | |
2454 | analyze_siv_subscript (tree chrec_a, | |
2455 | tree chrec_b, | |
d93817c4 ZD |
2456 | conflict_function **overlaps_a, |
2457 | conflict_function **overlaps_b, | |
5b78fc3e JS |
2458 | tree *last_conflicts, |
2459 | int loop_nest_num) | |
56cf8686 | 2460 | { |
0ff4040e SP |
2461 | dependence_stats.num_siv++; |
2462 | ||
56cf8686 SP |
2463 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2464 | fprintf (dump_file, "(analyze_siv_subscript \n"); | |
2465 | ||
2466 | if (evolution_function_is_constant_p (chrec_a) | |
5b78fc3e | 2467 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) |
56cf8686 | 2468 | analyze_siv_subscript_cst_affine (chrec_a, chrec_b, |
86df10e3 | 2469 | overlaps_a, overlaps_b, last_conflicts); |
56cf8686 | 2470 | |
5b78fc3e | 2471 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
56cf8686 | 2472 | && evolution_function_is_constant_p (chrec_b)) |
86df10e3 SP |
2473 | analyze_siv_subscript_cst_affine (chrec_b, chrec_a, |
2474 | overlaps_b, overlaps_a, last_conflicts); | |
56cf8686 | 2475 | |
5b78fc3e JS |
2476 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
2477 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) | |
0ff4040e SP |
2478 | { |
2479 | if (!chrec_contains_symbols (chrec_a) | |
2480 | && !chrec_contains_symbols (chrec_b)) | |
2481 | { | |
2482 | analyze_subscript_affine_affine (chrec_a, chrec_b, | |
2483 | overlaps_a, overlaps_b, | |
2484 | last_conflicts); | |
2485 | ||
d93817c4 ZD |
2486 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2487 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2488 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2489 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2490 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2491 | dependence_stats.num_siv_independent++; |
2492 | else | |
2493 | dependence_stats.num_siv_dependent++; | |
2494 | } | |
2495 | else if (can_use_analyze_subscript_affine_affine (&chrec_a, | |
2496 | &chrec_b)) | |
2497 | { | |
2498 | analyze_subscript_affine_affine (chrec_a, chrec_b, | |
2499 | overlaps_a, overlaps_b, | |
2500 | last_conflicts); | |
0ff4040e | 2501 | |
d93817c4 ZD |
2502 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2503 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2504 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2505 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2506 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2507 | dependence_stats.num_siv_independent++; |
2508 | else | |
2509 | dependence_stats.num_siv_dependent++; | |
2510 | } | |
2511 | else | |
2512 | goto siv_subscript_dontknow; | |
2513 | } | |
2514 | ||
56cf8686 SP |
2515 | else |
2516 | { | |
0ff4040e SP |
2517 | siv_subscript_dontknow:; |
2518 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2519 | fprintf (dump_file, "siv test failed: unimplemented.\n"); | |
d93817c4 ZD |
2520 | *overlaps_a = conflict_fn_not_known (); |
2521 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2522 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2523 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
2524 | } |
2525 | ||
2526 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2527 | fprintf (dump_file, ")\n"); | |
2528 | } | |
2529 | ||
55a700ac ZD |
2530 | /* Returns false if we can prove that the greatest common divisor of the steps |
2531 | of CHREC does not divide CST, false otherwise. */ | |
56cf8686 SP |
2532 | |
2533 | static bool | |
ed7a4b4b | 2534 | gcd_of_steps_may_divide_p (const_tree chrec, const_tree cst) |
56cf8686 | 2535 | { |
55a700ac ZD |
2536 | HOST_WIDE_INT cd = 0, val; |
2537 | tree step; | |
0ff4040e | 2538 | |
55a700ac ZD |
2539 | if (!host_integerp (cst, 0)) |
2540 | return true; | |
2541 | val = tree_low_cst (cst, 0); | |
2542 | ||
2543 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC) | |
2544 | { | |
2545 | step = CHREC_RIGHT (chrec); | |
2546 | if (!host_integerp (step, 0)) | |
2547 | return true; | |
2548 | cd = gcd (cd, tree_low_cst (step, 0)); | |
2549 | chrec = CHREC_LEFT (chrec); | |
56cf8686 | 2550 | } |
55a700ac ZD |
2551 | |
2552 | return val % cd == 0; | |
56cf8686 SP |
2553 | } |
2554 | ||
da9a21f4 SP |
2555 | /* Analyze a MIV (Multiple Index Variable) subscript with respect to |
2556 | LOOP_NEST. *OVERLAPS_A and *OVERLAPS_B are initialized to the | |
2557 | functions that describe the relation between the elements accessed | |
2558 | twice by CHREC_A and CHREC_B. For k >= 0, the following property | |
2559 | is verified: | |
56cf8686 SP |
2560 | |
2561 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2562 | ||
2563 | static void | |
2564 | analyze_miv_subscript (tree chrec_a, | |
2565 | tree chrec_b, | |
d93817c4 ZD |
2566 | conflict_function **overlaps_a, |
2567 | conflict_function **overlaps_b, | |
da9a21f4 SP |
2568 | tree *last_conflicts, |
2569 | struct loop *loop_nest) | |
56cf8686 SP |
2570 | { |
2571 | /* FIXME: This is a MIV subscript, not yet handled. | |
2572 | Example: (A[{1, +, 1}_1] vs. A[{1, +, 1}_2]) that comes from | |
2573 | (A[i] vs. A[j]). | |
2574 | ||
2575 | In the SIV test we had to solve a Diophantine equation with two | |
2576 | variables. In the MIV case we have to solve a Diophantine | |
2577 | equation with 2*n variables (if the subscript uses n IVs). | |
2578 | */ | |
33b30201 SP |
2579 | tree type, difference; |
2580 | ||
0ff4040e | 2581 | dependence_stats.num_miv++; |
56cf8686 SP |
2582 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2583 | fprintf (dump_file, "(analyze_miv_subscript \n"); | |
e2157b49 | 2584 | |
33b30201 | 2585 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
2586 | chrec_a = chrec_convert (type, chrec_a, NULL); |
2587 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 2588 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
56cf8686 | 2589 | |
e2157b49 | 2590 | if (eq_evolutions_p (chrec_a, chrec_b)) |
56cf8686 SP |
2591 | { |
2592 | /* Access functions are the same: all the elements are accessed | |
2593 | in the same order. */ | |
d93817c4 ZD |
2594 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2595 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
4839cb59 ZD |
2596 | *last_conflicts = estimated_loop_iterations_tree |
2597 | (get_chrec_loop (chrec_a), true); | |
0ff4040e | 2598 | dependence_stats.num_miv_dependent++; |
56cf8686 SP |
2599 | } |
2600 | ||
2601 | else if (evolution_function_is_constant_p (difference) | |
2602 | /* For the moment, the following is verified: | |
da9a21f4 SP |
2603 | evolution_function_is_affine_multivariate_p (chrec_a, |
2604 | loop_nest->num) */ | |
55a700ac | 2605 | && !gcd_of_steps_may_divide_p (chrec_a, difference)) |
56cf8686 SP |
2606 | { |
2607 | /* testsuite/.../ssa-chrec-33.c | |
2608 | {{21, +, 2}_1, +, -2}_2 vs. {{20, +, 2}_1, +, -2}_2 | |
0ff4040e | 2609 | |
55a700ac ZD |
2610 | The difference is 1, and all the evolution steps are multiples |
2611 | of 2, consequently there are no overlapping elements. */ | |
d93817c4 ZD |
2612 | *overlaps_a = conflict_fn_no_dependence (); |
2613 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2614 | *last_conflicts = integer_zero_node; |
0ff4040e | 2615 | dependence_stats.num_miv_independent++; |
56cf8686 SP |
2616 | } |
2617 | ||
da9a21f4 | 2618 | else if (evolution_function_is_affine_multivariate_p (chrec_a, loop_nest->num) |
0ff4040e | 2619 | && !chrec_contains_symbols (chrec_a) |
da9a21f4 | 2620 | && evolution_function_is_affine_multivariate_p (chrec_b, loop_nest->num) |
0ff4040e | 2621 | && !chrec_contains_symbols (chrec_b)) |
56cf8686 SP |
2622 | { |
2623 | /* testsuite/.../ssa-chrec-35.c | |
2624 | {0, +, 1}_2 vs. {0, +, 1}_3 | |
2625 | the overlapping elements are respectively located at iterations: | |
86df10e3 SP |
2626 | {0, +, 1}_x and {0, +, 1}_x, |
2627 | in other words, we have the equality: | |
2628 | {0, +, 1}_2 ({0, +, 1}_x) = {0, +, 1}_3 ({0, +, 1}_x) | |
2629 | ||
2630 | Other examples: | |
2631 | {{0, +, 1}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) = | |
2632 | {0, +, 1}_1 ({{0, +, 1}_x, +, 2}_y) | |
2633 | ||
2634 | {{0, +, 2}_1, +, 3}_2 ({0, +, 1}_y, {0, +, 1}_x) = | |
2635 | {{0, +, 3}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) | |
56cf8686 | 2636 | */ |
86df10e3 SP |
2637 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2638 | overlaps_a, overlaps_b, last_conflicts); | |
0ff4040e | 2639 | |
d93817c4 ZD |
2640 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2641 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2642 | dependence_stats.num_miv_unimplemented++; |
d93817c4 ZD |
2643 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2644 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2645 | dependence_stats.num_miv_independent++; |
2646 | else | |
2647 | dependence_stats.num_miv_dependent++; | |
56cf8686 SP |
2648 | } |
2649 | ||
2650 | else | |
2651 | { | |
2652 | /* When the analysis is too difficult, answer "don't know". */ | |
0ff4040e SP |
2653 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2654 | fprintf (dump_file, "analyze_miv_subscript test failed: unimplemented.\n"); | |
2655 | ||
d93817c4 ZD |
2656 | *overlaps_a = conflict_fn_not_known (); |
2657 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2658 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2659 | dependence_stats.num_miv_unimplemented++; |
56cf8686 SP |
2660 | } |
2661 | ||
2662 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2663 | fprintf (dump_file, ")\n"); | |
2664 | } | |
2665 | ||
da9a21f4 SP |
2666 | /* Determines the iterations for which CHREC_A is equal to CHREC_B in |
2667 | with respect to LOOP_NEST. OVERLAP_ITERATIONS_A and | |
2668 | OVERLAP_ITERATIONS_B are initialized with two functions that | |
2669 | describe the iterations that contain conflicting elements. | |
56cf8686 SP |
2670 | |
2671 | Remark: For an integer k >= 0, the following equality is true: | |
2672 | ||
2673 | CHREC_A (OVERLAP_ITERATIONS_A (k)) == CHREC_B (OVERLAP_ITERATIONS_B (k)). | |
2674 | */ | |
2675 | ||
2676 | static void | |
2677 | analyze_overlapping_iterations (tree chrec_a, | |
2678 | tree chrec_b, | |
d93817c4 ZD |
2679 | conflict_function **overlap_iterations_a, |
2680 | conflict_function **overlap_iterations_b, | |
da9a21f4 | 2681 | tree *last_conflicts, struct loop *loop_nest) |
56cf8686 | 2682 | { |
da9a21f4 SP |
2683 | unsigned int lnn = loop_nest->num; |
2684 | ||
0ff4040e SP |
2685 | dependence_stats.num_subscript_tests++; |
2686 | ||
56cf8686 SP |
2687 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2688 | { | |
2689 | fprintf (dump_file, "(analyze_overlapping_iterations \n"); | |
2690 | fprintf (dump_file, " (chrec_a = "); | |
2691 | print_generic_expr (dump_file, chrec_a, 0); | |
0ff4040e | 2692 | fprintf (dump_file, ")\n (chrec_b = "); |
56cf8686 SP |
2693 | print_generic_expr (dump_file, chrec_b, 0); |
2694 | fprintf (dump_file, ")\n"); | |
2695 | } | |
0ff4040e | 2696 | |
56cf8686 SP |
2697 | if (chrec_a == NULL_TREE |
2698 | || chrec_b == NULL_TREE | |
2699 | || chrec_contains_undetermined (chrec_a) | |
0ff4040e | 2700 | || chrec_contains_undetermined (chrec_b)) |
56cf8686 | 2701 | { |
0ff4040e SP |
2702 | dependence_stats.num_subscript_undetermined++; |
2703 | ||
d93817c4 ZD |
2704 | *overlap_iterations_a = conflict_fn_not_known (); |
2705 | *overlap_iterations_b = conflict_fn_not_known (); | |
56cf8686 | 2706 | } |
0ff4040e SP |
2707 | |
2708 | /* If they are the same chrec, and are affine, they overlap | |
2709 | on every iteration. */ | |
2710 | else if (eq_evolutions_p (chrec_a, chrec_b) | |
da9a21f4 | 2711 | && evolution_function_is_affine_multivariate_p (chrec_a, lnn)) |
0ff4040e SP |
2712 | { |
2713 | dependence_stats.num_same_subscript_function++; | |
d93817c4 ZD |
2714 | *overlap_iterations_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2715 | *overlap_iterations_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
0ff4040e SP |
2716 | *last_conflicts = chrec_dont_know; |
2717 | } | |
2718 | ||
2719 | /* If they aren't the same, and aren't affine, we can't do anything | |
2720 | yet. */ | |
2721 | else if ((chrec_contains_symbols (chrec_a) | |
2722 | || chrec_contains_symbols (chrec_b)) | |
da9a21f4 SP |
2723 | && (!evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
2724 | || !evolution_function_is_affine_multivariate_p (chrec_b, lnn))) | |
0ff4040e SP |
2725 | { |
2726 | dependence_stats.num_subscript_undetermined++; | |
d93817c4 ZD |
2727 | *overlap_iterations_a = conflict_fn_not_known (); |
2728 | *overlap_iterations_b = conflict_fn_not_known (); | |
0ff4040e SP |
2729 | } |
2730 | ||
56cf8686 SP |
2731 | else if (ziv_subscript_p (chrec_a, chrec_b)) |
2732 | analyze_ziv_subscript (chrec_a, chrec_b, | |
86df10e3 SP |
2733 | overlap_iterations_a, overlap_iterations_b, |
2734 | last_conflicts); | |
56cf8686 SP |
2735 | |
2736 | else if (siv_subscript_p (chrec_a, chrec_b)) | |
2737 | analyze_siv_subscript (chrec_a, chrec_b, | |
86df10e3 | 2738 | overlap_iterations_a, overlap_iterations_b, |
5b78fc3e | 2739 | last_conflicts, lnn); |
56cf8686 SP |
2740 | |
2741 | else | |
2742 | analyze_miv_subscript (chrec_a, chrec_b, | |
86df10e3 | 2743 | overlap_iterations_a, overlap_iterations_b, |
da9a21f4 | 2744 | last_conflicts, loop_nest); |
56cf8686 SP |
2745 | |
2746 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2747 | { | |
2748 | fprintf (dump_file, " (overlap_iterations_a = "); | |
d93817c4 | 2749 | dump_conflict_function (dump_file, *overlap_iterations_a); |
56cf8686 | 2750 | fprintf (dump_file, ")\n (overlap_iterations_b = "); |
d93817c4 | 2751 | dump_conflict_function (dump_file, *overlap_iterations_b); |
56cf8686 | 2752 | fprintf (dump_file, ")\n"); |
0ff4040e | 2753 | fprintf (dump_file, ")\n"); |
56cf8686 SP |
2754 | } |
2755 | } | |
2756 | ||
ba42e045 | 2757 | /* Helper function for uniquely inserting distance vectors. */ |
56cf8686 | 2758 | |
ba42e045 SP |
2759 | static void |
2760 | save_dist_v (struct data_dependence_relation *ddr, lambda_vector dist_v) | |
2761 | { | |
2762 | unsigned i; | |
2763 | lambda_vector v; | |
56cf8686 | 2764 | |
ba42e045 SP |
2765 | for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, v); i++) |
2766 | if (lambda_vector_equal (v, dist_v, DDR_NB_LOOPS (ddr))) | |
2767 | return; | |
56cf8686 | 2768 | |
ba42e045 SP |
2769 | VEC_safe_push (lambda_vector, heap, DDR_DIST_VECTS (ddr), dist_v); |
2770 | } | |
56cf8686 | 2771 | |
ba42e045 SP |
2772 | /* Helper function for uniquely inserting direction vectors. */ |
2773 | ||
2774 | static void | |
2775 | save_dir_v (struct data_dependence_relation *ddr, lambda_vector dir_v) | |
56cf8686 SP |
2776 | { |
2777 | unsigned i; | |
ba42e045 | 2778 | lambda_vector v; |
0ff4040e | 2779 | |
ba42e045 SP |
2780 | for (i = 0; VEC_iterate (lambda_vector, DDR_DIR_VECTS (ddr), i, v); i++) |
2781 | if (lambda_vector_equal (v, dir_v, DDR_NB_LOOPS (ddr))) | |
2782 | return; | |
2783 | ||
2784 | VEC_safe_push (lambda_vector, heap, DDR_DIR_VECTS (ddr), dir_v); | |
2785 | } | |
2786 | ||
2787 | /* Add a distance of 1 on all the loops outer than INDEX. If we | |
2788 | haven't yet determined a distance for this outer loop, push a new | |
2789 | distance vector composed of the previous distance, and a distance | |
2790 | of 1 for this outer loop. Example: | |
2791 | ||
2792 | | loop_1 | |
2793 | | loop_2 | |
2794 | | A[10] | |
2795 | | endloop_2 | |
2796 | | endloop_1 | |
2797 | ||
2798 | Saved vectors are of the form (dist_in_1, dist_in_2). First, we | |
2799 | save (0, 1), then we have to save (1, 0). */ | |
2800 | ||
2801 | static void | |
2802 | add_outer_distances (struct data_dependence_relation *ddr, | |
2803 | lambda_vector dist_v, int index) | |
2804 | { | |
2805 | /* For each outer loop where init_v is not set, the accesses are | |
2806 | in dependence of distance 1 in the loop. */ | |
2807 | while (--index >= 0) | |
2808 | { | |
2809 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
2810 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
2811 | save_v[index] = 1; | |
2812 | save_dist_v (ddr, save_v); | |
2813 | } | |
2814 | } | |
2815 | ||
2816 | /* Return false when fail to represent the data dependence as a | |
2817 | distance vector. INIT_B is set to true when a component has been | |
2818 | added to the distance vector DIST_V. INDEX_CARRY is then set to | |
2819 | the index in DIST_V that carries the dependence. */ | |
2820 | ||
2821 | static bool | |
2822 | build_classic_dist_vector_1 (struct data_dependence_relation *ddr, | |
2823 | struct data_reference *ddr_a, | |
2824 | struct data_reference *ddr_b, | |
2825 | lambda_vector dist_v, bool *init_b, | |
2826 | int *index_carry) | |
2827 | { | |
2828 | unsigned i; | |
2829 | lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
0ff4040e | 2830 | |
36d59cf7 | 2831 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
56cf8686 | 2832 | { |
86df10e3 | 2833 | tree access_fn_a, access_fn_b; |
36d59cf7 | 2834 | struct subscript *subscript = DDR_SUBSCRIPT (ddr, i); |
56cf8686 SP |
2835 | |
2836 | if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
2837 | { |
2838 | non_affine_dependence_relation (ddr); | |
ba42e045 | 2839 | return false; |
86df10e3 SP |
2840 | } |
2841 | ||
ba42e045 SP |
2842 | access_fn_a = DR_ACCESS_FN (ddr_a, i); |
2843 | access_fn_b = DR_ACCESS_FN (ddr_b, i); | |
56cf8686 | 2844 | |
86df10e3 SP |
2845 | if (TREE_CODE (access_fn_a) == POLYNOMIAL_CHREC |
2846 | && TREE_CODE (access_fn_b) == POLYNOMIAL_CHREC) | |
56cf8686 | 2847 | { |
ba42e045 SP |
2848 | int dist, index; |
2849 | int index_a = index_in_loop_nest (CHREC_VARIABLE (access_fn_a), | |
2850 | DDR_LOOP_NEST (ddr)); | |
2851 | int index_b = index_in_loop_nest (CHREC_VARIABLE (access_fn_b), | |
2852 | DDR_LOOP_NEST (ddr)); | |
86df10e3 SP |
2853 | |
2854 | /* The dependence is carried by the outermost loop. Example: | |
2855 | | loop_1 | |
2856 | | A[{4, +, 1}_1] | |
2857 | | loop_2 | |
2858 | | A[{5, +, 1}_2] | |
2859 | | endloop_2 | |
2860 | | endloop_1 | |
2861 | In this case, the dependence is carried by loop_1. */ | |
ba42e045 SP |
2862 | index = index_a < index_b ? index_a : index_b; |
2863 | *index_carry = MIN (index, *index_carry); | |
2864 | ||
86df10e3 SP |
2865 | if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) |
2866 | { | |
2867 | non_affine_dependence_relation (ddr); | |
ba42e045 | 2868 | return false; |
86df10e3 SP |
2869 | } |
2870 | ||
6b6fa4e9 | 2871 | dist = int_cst_value (SUB_DISTANCE (subscript)); |
56cf8686 | 2872 | |
ba42e045 SP |
2873 | /* This is the subscript coupling test. If we have already |
2874 | recorded a distance for this loop (a distance coming from | |
2875 | another subscript), it should be the same. For example, | |
2876 | in the following code, there is no dependence: | |
2877 | ||
56cf8686 SP |
2878 | | loop i = 0, N, 1 |
2879 | | T[i+1][i] = ... | |
2880 | | ... = T[i][i] | |
2881 | | endloop | |
ba42e045 SP |
2882 | */ |
2883 | if (init_v[index] != 0 && dist_v[index] != dist) | |
56cf8686 | 2884 | { |
36d59cf7 | 2885 | finalize_ddr_dependent (ddr, chrec_known); |
ba42e045 | 2886 | return false; |
56cf8686 SP |
2887 | } |
2888 | ||
ba42e045 SP |
2889 | dist_v[index] = dist; |
2890 | init_v[index] = 1; | |
2891 | *init_b = true; | |
2892 | } | |
a50411de | 2893 | else if (!operand_equal_p (access_fn_a, access_fn_b, 0)) |
ba42e045 SP |
2894 | { |
2895 | /* This can be for example an affine vs. constant dependence | |
2896 | (T[i] vs. T[3]) that is not an affine dependence and is | |
2897 | not representable as a distance vector. */ | |
2898 | non_affine_dependence_relation (ddr); | |
2899 | return false; | |
56cf8686 SP |
2900 | } |
2901 | } | |
304afda6 | 2902 | |
ba42e045 SP |
2903 | return true; |
2904 | } | |
304afda6 | 2905 | |
1baf2906 SP |
2906 | /* Return true when the DDR contains only constant access functions. */ |
2907 | ||
2908 | static bool | |
ed7a4b4b | 2909 | constant_access_functions (const struct data_dependence_relation *ddr) |
1baf2906 SP |
2910 | { |
2911 | unsigned i; | |
2912 | ||
2913 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
2914 | if (!evolution_function_is_constant_p (DR_ACCESS_FN (DDR_A (ddr), i)) | |
2915 | || !evolution_function_is_constant_p (DR_ACCESS_FN (DDR_B (ddr), i))) | |
2916 | return false; | |
2917 | ||
2918 | return true; | |
2919 | } | |
2920 | ||
ba42e045 | 2921 | /* Helper function for the case where DDR_A and DDR_B are the same |
097392de SP |
2922 | multivariate access function with a constant step. For an example |
2923 | see pr34635-1.c. */ | |
86df10e3 | 2924 | |
ba42e045 SP |
2925 | static void |
2926 | add_multivariate_self_dist (struct data_dependence_relation *ddr, tree c_2) | |
2927 | { | |
2928 | int x_1, x_2; | |
2929 | tree c_1 = CHREC_LEFT (c_2); | |
2930 | tree c_0 = CHREC_LEFT (c_1); | |
2931 | lambda_vector dist_v; | |
0ca2faee | 2932 | int v1, v2, cd; |
86df10e3 | 2933 | |
b1e75954 SP |
2934 | /* Polynomials with more than 2 variables are not handled yet. When |
2935 | the evolution steps are parameters, it is not possible to | |
2936 | represent the dependence using classical distance vectors. */ | |
2937 | if (TREE_CODE (c_0) != INTEGER_CST | |
2938 | || TREE_CODE (CHREC_RIGHT (c_1)) != INTEGER_CST | |
2939 | || TREE_CODE (CHREC_RIGHT (c_2)) != INTEGER_CST) | |
2940 | { | |
2941 | DDR_AFFINE_P (ddr) = false; | |
ba42e045 SP |
2942 | return; |
2943 | } | |
304afda6 | 2944 | |
ba42e045 SP |
2945 | x_2 = index_in_loop_nest (CHREC_VARIABLE (c_2), DDR_LOOP_NEST (ddr)); |
2946 | x_1 = index_in_loop_nest (CHREC_VARIABLE (c_1), DDR_LOOP_NEST (ddr)); | |
304afda6 | 2947 | |
ba42e045 SP |
2948 | /* For "{{0, +, 2}_1, +, 3}_2" the distance vector is (3, -2). */ |
2949 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
6b6fa4e9 SP |
2950 | v1 = int_cst_value (CHREC_RIGHT (c_1)); |
2951 | v2 = int_cst_value (CHREC_RIGHT (c_2)); | |
0ca2faee ZD |
2952 | cd = gcd (v1, v2); |
2953 | v1 /= cd; | |
2954 | v2 /= cd; | |
2955 | ||
2956 | if (v2 < 0) | |
2957 | { | |
2958 | v2 = -v2; | |
2959 | v1 = -v1; | |
2960 | } | |
2961 | ||
2962 | dist_v[x_1] = v2; | |
2963 | dist_v[x_2] = -v1; | |
ba42e045 | 2964 | save_dist_v (ddr, dist_v); |
304afda6 | 2965 | |
ba42e045 SP |
2966 | add_outer_distances (ddr, dist_v, x_1); |
2967 | } | |
304afda6 | 2968 | |
ba42e045 SP |
2969 | /* Helper function for the case where DDR_A and DDR_B are the same |
2970 | access functions. */ | |
37b8a73b | 2971 | |
ba42e045 SP |
2972 | static void |
2973 | add_other_self_distances (struct data_dependence_relation *ddr) | |
2974 | { | |
2975 | lambda_vector dist_v; | |
2976 | unsigned i; | |
2977 | int index_carry = DDR_NB_LOOPS (ddr); | |
304afda6 | 2978 | |
ba42e045 | 2979 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
37b8a73b | 2980 | { |
ba42e045 | 2981 | tree access_fun = DR_ACCESS_FN (DDR_A (ddr), i); |
304afda6 | 2982 | |
ba42e045 | 2983 | if (TREE_CODE (access_fun) == POLYNOMIAL_CHREC) |
304afda6 | 2984 | { |
ba42e045 SP |
2985 | if (!evolution_function_is_univariate_p (access_fun)) |
2986 | { | |
2987 | if (DDR_NUM_SUBSCRIPTS (ddr) != 1) | |
2988 | { | |
2989 | DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; | |
2990 | return; | |
2991 | } | |
2992 | ||
097392de SP |
2993 | access_fun = DR_ACCESS_FN (DDR_A (ddr), 0); |
2994 | ||
2995 | if (TREE_CODE (CHREC_LEFT (access_fun)) == POLYNOMIAL_CHREC) | |
2996 | add_multivariate_self_dist (ddr, access_fun); | |
2997 | else | |
2998 | /* The evolution step is not constant: it varies in | |
2999 | the outer loop, so this cannot be represented by a | |
3000 | distance vector. For example in pr34635.c the | |
3001 | evolution is {0, +, {0, +, 4}_1}_2. */ | |
3002 | DDR_AFFINE_P (ddr) = false; | |
3003 | ||
ba42e045 SP |
3004 | return; |
3005 | } | |
3006 | ||
3007 | index_carry = MIN (index_carry, | |
3008 | index_in_loop_nest (CHREC_VARIABLE (access_fun), | |
3009 | DDR_LOOP_NEST (ddr))); | |
304afda6 | 3010 | } |
37b8a73b SP |
3011 | } |
3012 | ||
ba42e045 SP |
3013 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3014 | add_outer_distances (ddr, dist_v, index_carry); | |
56cf8686 SP |
3015 | } |
3016 | ||
1baf2906 SP |
3017 | static void |
3018 | insert_innermost_unit_dist_vector (struct data_dependence_relation *ddr) | |
3019 | { | |
3020 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3021 | ||
3022 | dist_v[DDR_INNER_LOOP (ddr)] = 1; | |
3023 | save_dist_v (ddr, dist_v); | |
3024 | } | |
3025 | ||
3026 | /* Adds a unit distance vector to DDR when there is a 0 overlap. This | |
3027 | is the case for example when access functions are the same and | |
3028 | equal to a constant, as in: | |
3029 | ||
3030 | | loop_1 | |
3031 | | A[3] = ... | |
3032 | | ... = A[3] | |
3033 | | endloop_1 | |
3034 | ||
3035 | in which case the distance vectors are (0) and (1). */ | |
3036 | ||
3037 | static void | |
3038 | add_distance_for_zero_overlaps (struct data_dependence_relation *ddr) | |
3039 | { | |
3040 | unsigned i, j; | |
3041 | ||
3042 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3043 | { | |
3044 | subscript_p sub = DDR_SUBSCRIPT (ddr, i); | |
3045 | conflict_function *ca = SUB_CONFLICTS_IN_A (sub); | |
3046 | conflict_function *cb = SUB_CONFLICTS_IN_B (sub); | |
3047 | ||
3048 | for (j = 0; j < ca->n; j++) | |
3049 | if (affine_function_zero_p (ca->fns[j])) | |
3050 | { | |
3051 | insert_innermost_unit_dist_vector (ddr); | |
3052 | return; | |
3053 | } | |
3054 | ||
3055 | for (j = 0; j < cb->n; j++) | |
3056 | if (affine_function_zero_p (cb->fns[j])) | |
3057 | { | |
3058 | insert_innermost_unit_dist_vector (ddr); | |
3059 | return; | |
3060 | } | |
3061 | } | |
3062 | } | |
3063 | ||
ba42e045 SP |
3064 | /* Compute the classic per loop distance vector. DDR is the data |
3065 | dependence relation to build a vector from. Return false when fail | |
3066 | to represent the data dependence as a distance vector. */ | |
56cf8686 | 3067 | |
464f49d8 | 3068 | static bool |
da9a21f4 SP |
3069 | build_classic_dist_vector (struct data_dependence_relation *ddr, |
3070 | struct loop *loop_nest) | |
56cf8686 | 3071 | { |
304afda6 | 3072 | bool init_b = false; |
ba42e045 SP |
3073 | int index_carry = DDR_NB_LOOPS (ddr); |
3074 | lambda_vector dist_v; | |
304afda6 | 3075 | |
36d59cf7 | 3076 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
2f470326 | 3077 | return false; |
ba42e045 SP |
3078 | |
3079 | if (same_access_functions (ddr)) | |
56cf8686 | 3080 | { |
ba42e045 SP |
3081 | /* Save the 0 vector. */ |
3082 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3083 | save_dist_v (ddr, dist_v); | |
56cf8686 | 3084 | |
1baf2906 SP |
3085 | if (constant_access_functions (ddr)) |
3086 | add_distance_for_zero_overlaps (ddr); | |
3087 | ||
ba42e045 SP |
3088 | if (DDR_NB_LOOPS (ddr) > 1) |
3089 | add_other_self_distances (ddr); | |
86df10e3 | 3090 | |
ba42e045 SP |
3091 | return true; |
3092 | } | |
86df10e3 | 3093 | |
ba42e045 SP |
3094 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3095 | if (!build_classic_dist_vector_1 (ddr, DDR_A (ddr), DDR_B (ddr), | |
3096 | dist_v, &init_b, &index_carry)) | |
3097 | return false; | |
86df10e3 | 3098 | |
ba42e045 SP |
3099 | /* Save the distance vector if we initialized one. */ |
3100 | if (init_b) | |
3101 | { | |
3102 | /* Verify a basic constraint: classic distance vectors should | |
3103 | always be lexicographically positive. | |
3104 | ||
3105 | Data references are collected in the order of execution of | |
3106 | the program, thus for the following loop | |
3107 | ||
3108 | | for (i = 1; i < 100; i++) | |
3109 | | for (j = 1; j < 100; j++) | |
3110 | | { | |
3111 | | t = T[j+1][i-1]; // A | |
3112 | | T[j][i] = t + 2; // B | |
3113 | | } | |
3114 | ||
3115 | references are collected following the direction of the wind: | |
3116 | A then B. The data dependence tests are performed also | |
3117 | following this order, such that we're looking at the distance | |
3118 | separating the elements accessed by A from the elements later | |
3119 | accessed by B. But in this example, the distance returned by | |
3120 | test_dep (A, B) is lexicographically negative (-1, 1), that | |
3121 | means that the access A occurs later than B with respect to | |
3122 | the outer loop, ie. we're actually looking upwind. In this | |
3123 | case we solve test_dep (B, A) looking downwind to the | |
3124 | lexicographically positive solution, that returns the | |
3125 | distance vector (1, -1). */ | |
3126 | if (!lambda_vector_lexico_pos (dist_v, DDR_NB_LOOPS (ddr))) | |
3127 | { | |
3128 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
2f470326 JJ |
3129 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3130 | loop_nest)) | |
3131 | return false; | |
ba42e045 | 3132 | compute_subscript_distance (ddr); |
2f470326 JJ |
3133 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3134 | save_v, &init_b, &index_carry)) | |
3135 | return false; | |
ba42e045 | 3136 | save_dist_v (ddr, save_v); |
71d5b5e1 | 3137 | DDR_REVERSED_P (ddr) = true; |
ba42e045 SP |
3138 | |
3139 | /* In this case there is a dependence forward for all the | |
3140 | outer loops: | |
3141 | ||
3142 | | for (k = 1; k < 100; k++) | |
3143 | | for (i = 1; i < 100; i++) | |
3144 | | for (j = 1; j < 100; j++) | |
3145 | | { | |
3146 | | t = T[j+1][i-1]; // A | |
3147 | | T[j][i] = t + 2; // B | |
3148 | | } | |
3149 | ||
3150 | the vectors are: | |
3151 | (0, 1, -1) | |
3152 | (1, 1, -1) | |
3153 | (1, -1, 1) | |
3154 | */ | |
3155 | if (DDR_NB_LOOPS (ddr) > 1) | |
3156 | { | |
3157 | add_outer_distances (ddr, save_v, index_carry); | |
3158 | add_outer_distances (ddr, dist_v, index_carry); | |
86df10e3 | 3159 | } |
ba42e045 SP |
3160 | } |
3161 | else | |
3162 | { | |
3163 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3164 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3165 | |
ba42e045 | 3166 | if (DDR_NB_LOOPS (ddr) > 1) |
56cf8686 | 3167 | { |
ba42e045 | 3168 | lambda_vector opposite_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
86df10e3 | 3169 | |
2f470326 JJ |
3170 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), |
3171 | DDR_A (ddr), loop_nest)) | |
3172 | return false; | |
ba42e045 | 3173 | compute_subscript_distance (ddr); |
2f470326 JJ |
3174 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3175 | opposite_v, &init_b, | |
3176 | &index_carry)) | |
3177 | return false; | |
86df10e3 | 3178 | |
2f470326 | 3179 | save_dist_v (ddr, save_v); |
ba42e045 SP |
3180 | add_outer_distances (ddr, dist_v, index_carry); |
3181 | add_outer_distances (ddr, opposite_v, index_carry); | |
56cf8686 | 3182 | } |
2f470326 JJ |
3183 | else |
3184 | save_dist_v (ddr, save_v); | |
56cf8686 SP |
3185 | } |
3186 | } | |
ba42e045 SP |
3187 | else |
3188 | { | |
3189 | /* There is a distance of 1 on all the outer loops: Example: | |
3190 | there is a dependence of distance 1 on loop_1 for the array A. | |
304afda6 | 3191 | |
ba42e045 SP |
3192 | | loop_1 |
3193 | | A[5] = ... | |
3194 | | endloop | |
3195 | */ | |
3196 | add_outer_distances (ddr, dist_v, | |
3197 | lambda_vector_first_nz (dist_v, | |
3198 | DDR_NB_LOOPS (ddr), 0)); | |
3199 | } | |
3200 | ||
3201 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
304afda6 | 3202 | { |
ba42e045 | 3203 | unsigned i; |
304afda6 | 3204 | |
ba42e045 SP |
3205 | fprintf (dump_file, "(build_classic_dist_vector\n"); |
3206 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3207 | { | |
3208 | fprintf (dump_file, " dist_vector = ("); | |
3209 | print_lambda_vector (dump_file, DDR_DIST_VECT (ddr, i), | |
3210 | DDR_NB_LOOPS (ddr)); | |
3211 | fprintf (dump_file, " )\n"); | |
3212 | } | |
3213 | fprintf (dump_file, ")\n"); | |
304afda6 SP |
3214 | } |
3215 | ||
ba42e045 SP |
3216 | return true; |
3217 | } | |
56cf8686 | 3218 | |
ba42e045 SP |
3219 | /* Return the direction for a given distance. |
3220 | FIXME: Computing dir this way is suboptimal, since dir can catch | |
3221 | cases that dist is unable to represent. */ | |
86df10e3 | 3222 | |
ba42e045 SP |
3223 | static inline enum data_dependence_direction |
3224 | dir_from_dist (int dist) | |
3225 | { | |
3226 | if (dist > 0) | |
3227 | return dir_positive; | |
3228 | else if (dist < 0) | |
3229 | return dir_negative; | |
3230 | else | |
3231 | return dir_equal; | |
3232 | } | |
304afda6 | 3233 | |
ba42e045 SP |
3234 | /* Compute the classic per loop direction vector. DDR is the data |
3235 | dependence relation to build a vector from. */ | |
304afda6 | 3236 | |
ba42e045 SP |
3237 | static void |
3238 | build_classic_dir_vector (struct data_dependence_relation *ddr) | |
3239 | { | |
3240 | unsigned i, j; | |
3241 | lambda_vector dist_v; | |
86df10e3 | 3242 | |
ba42e045 SP |
3243 | for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, dist_v); i++) |
3244 | { | |
3245 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3246 | |
ba42e045 SP |
3247 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) |
3248 | dir_v[j] = dir_from_dist (dist_v[j]); | |
304afda6 | 3249 | |
ba42e045 SP |
3250 | save_dir_v (ddr, dir_v); |
3251 | } | |
56cf8686 SP |
3252 | } |
3253 | ||
ba42e045 SP |
3254 | /* Helper function. Returns true when there is a dependence between |
3255 | data references DRA and DRB. */ | |
0ff4040e | 3256 | |
ba42e045 SP |
3257 | static bool |
3258 | subscript_dependence_tester_1 (struct data_dependence_relation *ddr, | |
3259 | struct data_reference *dra, | |
da9a21f4 SP |
3260 | struct data_reference *drb, |
3261 | struct loop *loop_nest) | |
0ff4040e SP |
3262 | { |
3263 | unsigned int i; | |
0ff4040e | 3264 | tree last_conflicts; |
ebf78a47 | 3265 | struct subscript *subscript; |
ba42e045 | 3266 | |
ebf78a47 SP |
3267 | for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript); |
3268 | i++) | |
0ff4040e | 3269 | { |
d93817c4 | 3270 | conflict_function *overlaps_a, *overlaps_b; |
ebf78a47 | 3271 | |
0ff4040e SP |
3272 | analyze_overlapping_iterations (DR_ACCESS_FN (dra, i), |
3273 | DR_ACCESS_FN (drb, i), | |
3274 | &overlaps_a, &overlaps_b, | |
da9a21f4 | 3275 | &last_conflicts, loop_nest); |
ebf78a47 | 3276 | |
d93817c4 ZD |
3277 | if (CF_NOT_KNOWN_P (overlaps_a) |
3278 | || CF_NOT_KNOWN_P (overlaps_b)) | |
0ff4040e SP |
3279 | { |
3280 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
3281 | dependence_stats.num_dependence_undetermined++; | |
d93817c4 ZD |
3282 | free_conflict_function (overlaps_a); |
3283 | free_conflict_function (overlaps_b); | |
ba42e045 | 3284 | return false; |
0ff4040e | 3285 | } |
ebf78a47 | 3286 | |
d93817c4 ZD |
3287 | else if (CF_NO_DEPENDENCE_P (overlaps_a) |
3288 | || CF_NO_DEPENDENCE_P (overlaps_b)) | |
0ff4040e SP |
3289 | { |
3290 | finalize_ddr_dependent (ddr, chrec_known); | |
3291 | dependence_stats.num_dependence_independent++; | |
d93817c4 ZD |
3292 | free_conflict_function (overlaps_a); |
3293 | free_conflict_function (overlaps_b); | |
ba42e045 | 3294 | return false; |
0ff4040e | 3295 | } |
ebf78a47 | 3296 | |
0ff4040e SP |
3297 | else |
3298 | { | |
6935bae7 SP |
3299 | if (SUB_CONFLICTS_IN_A (subscript)) |
3300 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
3301 | if (SUB_CONFLICTS_IN_B (subscript)) | |
3302 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
3303 | ||
0ff4040e SP |
3304 | SUB_CONFLICTS_IN_A (subscript) = overlaps_a; |
3305 | SUB_CONFLICTS_IN_B (subscript) = overlaps_b; | |
3306 | SUB_LAST_CONFLICT (subscript) = last_conflicts; | |
3307 | } | |
3308 | } | |
3309 | ||
ba42e045 SP |
3310 | return true; |
3311 | } | |
3312 | ||
da9a21f4 | 3313 | /* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */ |
ba42e045 SP |
3314 | |
3315 | static void | |
da9a21f4 SP |
3316 | subscript_dependence_tester (struct data_dependence_relation *ddr, |
3317 | struct loop *loop_nest) | |
ba42e045 SP |
3318 | { |
3319 | ||
3320 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3321 | fprintf (dump_file, "(subscript_dependence_tester \n"); | |
3322 | ||
da9a21f4 | 3323 | if (subscript_dependence_tester_1 (ddr, DDR_A (ddr), DDR_B (ddr), loop_nest)) |
ba42e045 | 3324 | dependence_stats.num_dependence_dependent++; |
0ff4040e | 3325 | |
0ff4040e | 3326 | compute_subscript_distance (ddr); |
da9a21f4 | 3327 | if (build_classic_dist_vector (ddr, loop_nest)) |
ba42e045 | 3328 | build_classic_dir_vector (ddr); |
0ff4040e SP |
3329 | |
3330 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3331 | fprintf (dump_file, ")\n"); | |
3332 | } | |
3333 | ||
56cf8686 | 3334 | /* Returns true when all the access functions of A are affine or |
da9a21f4 | 3335 | constant with respect to LOOP_NEST. */ |
56cf8686 SP |
3336 | |
3337 | static bool | |
ed7a4b4b KG |
3338 | access_functions_are_affine_or_constant_p (const struct data_reference *a, |
3339 | const struct loop *loop_nest) | |
56cf8686 SP |
3340 | { |
3341 | unsigned int i; | |
3d8864c0 | 3342 | VEC(tree,heap) *fns = DR_ACCESS_FNS (a); |
9cbb7989 | 3343 | tree t; |
3d8864c0 SP |
3344 | |
3345 | for (i = 0; VEC_iterate (tree, fns, i, t); i++) | |
da9a21f4 SP |
3346 | if (!evolution_function_is_invariant_p (t, loop_nest->num) |
3347 | && !evolution_function_is_affine_multivariate_p (t, loop_nest->num)) | |
56cf8686 SP |
3348 | return false; |
3349 | ||
3350 | return true; | |
3351 | } | |
3352 | ||
3d8864c0 SP |
3353 | /* Initializes an equation for an OMEGA problem using the information |
3354 | contained in the ACCESS_FUN. Returns true when the operation | |
3355 | succeeded. | |
3356 | ||
3357 | PB is the omega constraint system. | |
3358 | EQ is the number of the equation to be initialized. | |
3359 | OFFSET is used for shifting the variables names in the constraints: | |
3360 | a constrain is composed of 2 * the number of variables surrounding | |
3361 | dependence accesses. OFFSET is set either to 0 for the first n variables, | |
3362 | then it is set to n. | |
3363 | ACCESS_FUN is expected to be an affine chrec. */ | |
3364 | ||
3365 | static bool | |
3366 | init_omega_eq_with_af (omega_pb pb, unsigned eq, | |
3367 | unsigned int offset, tree access_fun, | |
3368 | struct data_dependence_relation *ddr) | |
3369 | { | |
3370 | switch (TREE_CODE (access_fun)) | |
3371 | { | |
3372 | case POLYNOMIAL_CHREC: | |
3373 | { | |
3374 | tree left = CHREC_LEFT (access_fun); | |
3375 | tree right = CHREC_RIGHT (access_fun); | |
3376 | int var = CHREC_VARIABLE (access_fun); | |
3377 | unsigned var_idx; | |
3378 | ||
3379 | if (TREE_CODE (right) != INTEGER_CST) | |
3380 | return false; | |
3381 | ||
3382 | var_idx = index_in_loop_nest (var, DDR_LOOP_NEST (ddr)); | |
6b6fa4e9 | 3383 | pb->eqs[eq].coef[offset + var_idx + 1] = int_cst_value (right); |
3d8864c0 SP |
3384 | |
3385 | /* Compute the innermost loop index. */ | |
3386 | DDR_INNER_LOOP (ddr) = MAX (DDR_INNER_LOOP (ddr), var_idx); | |
3387 | ||
3388 | if (offset == 0) | |
3389 | pb->eqs[eq].coef[var_idx + DDR_NB_LOOPS (ddr) + 1] | |
6b6fa4e9 | 3390 | += int_cst_value (right); |
3d8864c0 SP |
3391 | |
3392 | switch (TREE_CODE (left)) | |
3393 | { | |
3394 | case POLYNOMIAL_CHREC: | |
3395 | return init_omega_eq_with_af (pb, eq, offset, left, ddr); | |
3396 | ||
3397 | case INTEGER_CST: | |
6b6fa4e9 | 3398 | pb->eqs[eq].coef[0] += int_cst_value (left); |
3d8864c0 SP |
3399 | return true; |
3400 | ||
3401 | default: | |
3402 | return false; | |
3403 | } | |
3404 | } | |
3405 | ||
3406 | case INTEGER_CST: | |
6b6fa4e9 | 3407 | pb->eqs[eq].coef[0] += int_cst_value (access_fun); |
3d8864c0 SP |
3408 | return true; |
3409 | ||
3410 | default: | |
3411 | return false; | |
3412 | } | |
3413 | } | |
3414 | ||
3415 | /* As explained in the comments preceding init_omega_for_ddr, we have | |
3416 | to set up a system for each loop level, setting outer loops | |
3417 | variation to zero, and current loop variation to positive or zero. | |
3418 | Save each lexico positive distance vector. */ | |
3419 | ||
3420 | static void | |
3421 | omega_extract_distance_vectors (omega_pb pb, | |
3422 | struct data_dependence_relation *ddr) | |
3423 | { | |
3424 | int eq, geq; | |
3425 | unsigned i, j; | |
3426 | struct loop *loopi, *loopj; | |
3427 | enum omega_result res; | |
3428 | ||
3429 | /* Set a new problem for each loop in the nest. The basis is the | |
3430 | problem that we have initialized until now. On top of this we | |
3431 | add new constraints. */ | |
3432 | for (i = 0; i <= DDR_INNER_LOOP (ddr) | |
3433 | && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++) | |
3434 | { | |
3435 | int dist = 0; | |
3436 | omega_pb copy = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), | |
3437 | DDR_NB_LOOPS (ddr)); | |
3438 | ||
3439 | omega_copy_problem (copy, pb); | |
3440 | ||
3441 | /* For all the outer loops "loop_j", add "dj = 0". */ | |
3442 | for (j = 0; | |
3443 | j < i && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), j, loopj); j++) | |
3444 | { | |
3445 | eq = omega_add_zero_eq (copy, omega_black); | |
3446 | copy->eqs[eq].coef[j + 1] = 1; | |
3447 | } | |
3448 | ||
3449 | /* For "loop_i", add "0 <= di". */ | |
3450 | geq = omega_add_zero_geq (copy, omega_black); | |
3451 | copy->geqs[geq].coef[i + 1] = 1; | |
3452 | ||
3453 | /* Reduce the constraint system, and test that the current | |
3454 | problem is feasible. */ | |
3455 | res = omega_simplify_problem (copy); | |
3456 | if (res == omega_false | |
3457 | || res == omega_unknown | |
3458 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3459 | goto next_problem; | |
3460 | ||
3461 | for (eq = 0; eq < copy->num_subs; eq++) | |
3462 | if (copy->subs[eq].key == (int) i + 1) | |
3463 | { | |
3464 | dist = copy->subs[eq].coef[0]; | |
3465 | goto found_dist; | |
3466 | } | |
3467 | ||
3468 | if (dist == 0) | |
3469 | { | |
3470 | /* Reinitialize problem... */ | |
3471 | omega_copy_problem (copy, pb); | |
3472 | for (j = 0; | |
3473 | j < i && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), j, loopj); j++) | |
3474 | { | |
3475 | eq = omega_add_zero_eq (copy, omega_black); | |
3476 | copy->eqs[eq].coef[j + 1] = 1; | |
3477 | } | |
3478 | ||
3479 | /* ..., but this time "di = 1". */ | |
3480 | eq = omega_add_zero_eq (copy, omega_black); | |
3481 | copy->eqs[eq].coef[i + 1] = 1; | |
3482 | copy->eqs[eq].coef[0] = -1; | |
3483 | ||
3484 | res = omega_simplify_problem (copy); | |
3485 | if (res == omega_false | |
3486 | || res == omega_unknown | |
3487 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3488 | goto next_problem; | |
3489 | ||
3490 | for (eq = 0; eq < copy->num_subs; eq++) | |
3491 | if (copy->subs[eq].key == (int) i + 1) | |
3492 | { | |
3493 | dist = copy->subs[eq].coef[0]; | |
3494 | goto found_dist; | |
3495 | } | |
3496 | } | |
3497 | ||
3498 | found_dist:; | |
3499 | /* Save the lexicographically positive distance vector. */ | |
3500 | if (dist >= 0) | |
3501 | { | |
3502 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3503 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3504 | ||
3505 | dist_v[i] = dist; | |
3506 | ||
3507 | for (eq = 0; eq < copy->num_subs; eq++) | |
3508 | if (copy->subs[eq].key > 0) | |
3509 | { | |
3510 | dist = copy->subs[eq].coef[0]; | |
3511 | dist_v[copy->subs[eq].key - 1] = dist; | |
3512 | } | |
3513 | ||
3514 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3515 | dir_v[j] = dir_from_dist (dist_v[j]); | |
3516 | ||
3517 | save_dist_v (ddr, dist_v); | |
3518 | save_dir_v (ddr, dir_v); | |
3519 | } | |
3520 | ||
3521 | next_problem:; | |
3522 | omega_free_problem (copy); | |
3523 | } | |
3524 | } | |
3525 | ||
3526 | /* This is called for each subscript of a tuple of data references: | |
3527 | insert an equality for representing the conflicts. */ | |
3528 | ||
3529 | static bool | |
3530 | omega_setup_subscript (tree access_fun_a, tree access_fun_b, | |
3531 | struct data_dependence_relation *ddr, | |
3532 | omega_pb pb, bool *maybe_dependent) | |
3533 | { | |
3534 | int eq; | |
33b30201 SP |
3535 | tree type = signed_type_for_types (TREE_TYPE (access_fun_a), |
3536 | TREE_TYPE (access_fun_b)); | |
726a989a RB |
3537 | tree fun_a = chrec_convert (type, access_fun_a, NULL); |
3538 | tree fun_b = chrec_convert (type, access_fun_b, NULL); | |
33b30201 | 3539 | tree difference = chrec_fold_minus (type, fun_a, fun_b); |
3d8864c0 SP |
3540 | |
3541 | /* When the fun_a - fun_b is not constant, the dependence is not | |
3542 | captured by the classic distance vector representation. */ | |
3543 | if (TREE_CODE (difference) != INTEGER_CST) | |
3544 | return false; | |
3545 | ||
3546 | /* ZIV test. */ | |
3547 | if (ziv_subscript_p (fun_a, fun_b) && !integer_zerop (difference)) | |
3548 | { | |
3549 | /* There is no dependence. */ | |
3550 | *maybe_dependent = false; | |
3551 | return true; | |
3552 | } | |
3553 | ||
33b30201 | 3554 | fun_b = chrec_fold_multiply (type, fun_b, integer_minus_one_node); |
3d8864c0 SP |
3555 | |
3556 | eq = omega_add_zero_eq (pb, omega_black); | |
3557 | if (!init_omega_eq_with_af (pb, eq, DDR_NB_LOOPS (ddr), fun_a, ddr) | |
3558 | || !init_omega_eq_with_af (pb, eq, 0, fun_b, ddr)) | |
3559 | /* There is probably a dependence, but the system of | |
3560 | constraints cannot be built: answer "don't know". */ | |
3561 | return false; | |
3562 | ||
3563 | /* GCD test. */ | |
3564 | if (DDR_NB_LOOPS (ddr) != 0 && pb->eqs[eq].coef[0] | |
3565 | && !int_divides_p (lambda_vector_gcd | |
3566 | ((lambda_vector) &(pb->eqs[eq].coef[1]), | |
3567 | 2 * DDR_NB_LOOPS (ddr)), | |
3568 | pb->eqs[eq].coef[0])) | |
3569 | { | |
3570 | /* There is no dependence. */ | |
3571 | *maybe_dependent = false; | |
3572 | return true; | |
3573 | } | |
3574 | ||
3575 | return true; | |
3576 | } | |
3577 | ||
3578 | /* Helper function, same as init_omega_for_ddr but specialized for | |
3579 | data references A and B. */ | |
3580 | ||
3581 | static bool | |
3582 | init_omega_for_ddr_1 (struct data_reference *dra, struct data_reference *drb, | |
3583 | struct data_dependence_relation *ddr, | |
3584 | omega_pb pb, bool *maybe_dependent) | |
3585 | { | |
3586 | unsigned i; | |
3587 | int ineq; | |
3588 | struct loop *loopi; | |
3589 | unsigned nb_loops = DDR_NB_LOOPS (ddr); | |
3590 | ||
3591 | /* Insert an equality per subscript. */ | |
3592 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3593 | { | |
3594 | if (!omega_setup_subscript (DR_ACCESS_FN (dra, i), DR_ACCESS_FN (drb, i), | |
3595 | ddr, pb, maybe_dependent)) | |
3596 | return false; | |
3597 | else if (*maybe_dependent == false) | |
3598 | { | |
3599 | /* There is no dependence. */ | |
3600 | DDR_ARE_DEPENDENT (ddr) = chrec_known; | |
3601 | return true; | |
3602 | } | |
3603 | } | |
3604 | ||
3605 | /* Insert inequalities: constraints corresponding to the iteration | |
3606 | domain, i.e. the loops surrounding the references "loop_x" and | |
3607 | the distance variables "dx". The layout of the OMEGA | |
3608 | representation is as follows: | |
3609 | - coef[0] is the constant | |
3610 | - coef[1..nb_loops] are the protected variables that will not be | |
3611 | removed by the solver: the "dx" | |
3612 | - coef[nb_loops + 1, 2*nb_loops] are the loop variables: "loop_x". | |
3613 | */ | |
3614 | for (i = 0; i <= DDR_INNER_LOOP (ddr) | |
3615 | && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++) | |
3616 | { | |
fd727b34 | 3617 | HOST_WIDE_INT nbi = estimated_loop_iterations_int (loopi, false); |
3d8864c0 SP |
3618 | |
3619 | /* 0 <= loop_x */ | |
3620 | ineq = omega_add_zero_geq (pb, omega_black); | |
3621 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3622 | ||
3623 | /* 0 <= loop_x + dx */ | |
3624 | ineq = omega_add_zero_geq (pb, omega_black); | |
3625 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3626 | pb->geqs[ineq].coef[i + 1] = 1; | |
3627 | ||
3628 | if (nbi != -1) | |
3629 | { | |
3630 | /* loop_x <= nb_iters */ | |
3631 | ineq = omega_add_zero_geq (pb, omega_black); | |
3632 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3633 | pb->geqs[ineq].coef[0] = nbi; | |
3634 | ||
3635 | /* loop_x + dx <= nb_iters */ | |
3636 | ineq = omega_add_zero_geq (pb, omega_black); | |
3637 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3638 | pb->geqs[ineq].coef[i + 1] = -1; | |
3639 | pb->geqs[ineq].coef[0] = nbi; | |
3640 | ||
3641 | /* A step "dx" bigger than nb_iters is not feasible, so | |
3642 | add "0 <= nb_iters + dx", */ | |
3643 | ineq = omega_add_zero_geq (pb, omega_black); | |
3644 | pb->geqs[ineq].coef[i + 1] = 1; | |
3645 | pb->geqs[ineq].coef[0] = nbi; | |
3646 | /* and "dx <= nb_iters". */ | |
3647 | ineq = omega_add_zero_geq (pb, omega_black); | |
3648 | pb->geqs[ineq].coef[i + 1] = -1; | |
3649 | pb->geqs[ineq].coef[0] = nbi; | |
3650 | } | |
3651 | } | |
3652 | ||
3653 | omega_extract_distance_vectors (pb, ddr); | |
3654 | ||
3655 | return true; | |
3656 | } | |
3657 | ||
3658 | /* Sets up the Omega dependence problem for the data dependence | |
3659 | relation DDR. Returns false when the constraint system cannot be | |
3660 | built, ie. when the test answers "don't know". Returns true | |
3661 | otherwise, and when independence has been proved (using one of the | |
3662 | trivial dependence test), set MAYBE_DEPENDENT to false, otherwise | |
3663 | set MAYBE_DEPENDENT to true. | |
3664 | ||
3665 | Example: for setting up the dependence system corresponding to the | |
3666 | conflicting accesses | |
3667 | ||
3668 | | loop_i | |
3669 | | loop_j | |
3670 | | A[i, i+1] = ... | |
3671 | | ... A[2*j, 2*(i + j)] | |
3672 | | endloop_j | |
3673 | | endloop_i | |
3674 | ||
3675 | the following constraints come from the iteration domain: | |
3676 | ||
3677 | 0 <= i <= Ni | |
3678 | 0 <= i + di <= Ni | |
3679 | 0 <= j <= Nj | |
3680 | 0 <= j + dj <= Nj | |
3681 | ||
3682 | where di, dj are the distance variables. The constraints | |
3683 | representing the conflicting elements are: | |
3684 | ||
3685 | i = 2 * (j + dj) | |
3686 | i + 1 = 2 * (i + di + j + dj) | |
3687 | ||
3688 | For asking that the resulting distance vector (di, dj) be | |
3689 | lexicographically positive, we insert the constraint "di >= 0". If | |
3690 | "di = 0" in the solution, we fix that component to zero, and we | |
3691 | look at the inner loops: we set a new problem where all the outer | |
3692 | loop distances are zero, and fix this inner component to be | |
3693 | positive. When one of the components is positive, we save that | |
3694 | distance, and set a new problem where the distance on this loop is | |
3695 | zero, searching for other distances in the inner loops. Here is | |
3696 | the classic example that illustrates that we have to set for each | |
3697 | inner loop a new problem: | |
3698 | ||
3699 | | loop_1 | |
3700 | | loop_2 | |
3701 | | A[10] | |
3702 | | endloop_2 | |
3703 | | endloop_1 | |
3704 | ||
3705 | we have to save two distances (1, 0) and (0, 1). | |
3706 | ||
3707 | Given two array references, refA and refB, we have to set the | |
3708 | dependence problem twice, refA vs. refB and refB vs. refA, and we | |
3709 | cannot do a single test, as refB might occur before refA in the | |
3710 | inner loops, and the contrary when considering outer loops: ex. | |
3711 | ||
3712 | | loop_0 | |
3713 | | loop_1 | |
3714 | | loop_2 | |
3715 | | T[{1,+,1}_2][{1,+,1}_1] // refA | |
3716 | | T[{2,+,1}_2][{0,+,1}_1] // refB | |
3717 | | endloop_2 | |
3718 | | endloop_1 | |
3719 | | endloop_0 | |
3720 | ||
3721 | refB touches the elements in T before refA, and thus for the same | |
3722 | loop_0 refB precedes refA: ie. the distance vector (0, 1, -1) | |
3723 | but for successive loop_0 iterations, we have (1, -1, 1) | |
3724 | ||
3725 | The Omega solver expects the distance variables ("di" in the | |
3726 | previous example) to come first in the constraint system (as | |
3727 | variables to be protected, or "safe" variables), the constraint | |
3728 | system is built using the following layout: | |
3729 | ||
3730 | "cst | distance vars | index vars". | |
3731 | */ | |
3732 | ||
3733 | static bool | |
3734 | init_omega_for_ddr (struct data_dependence_relation *ddr, | |
3735 | bool *maybe_dependent) | |
3736 | { | |
3737 | omega_pb pb; | |
3738 | bool res = false; | |
3739 | ||
3740 | *maybe_dependent = true; | |
3741 | ||
3742 | if (same_access_functions (ddr)) | |
3743 | { | |
3744 | unsigned j; | |
3745 | lambda_vector dir_v; | |
3746 | ||
3747 | /* Save the 0 vector. */ | |
3748 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
3749 | dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3750 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3751 | dir_v[j] = dir_equal; | |
3752 | save_dir_v (ddr, dir_v); | |
3753 | ||
3754 | /* Save the dependences carried by outer loops. */ | |
3755 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
3756 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
3757 | maybe_dependent); | |
3758 | omega_free_problem (pb); | |
3759 | return res; | |
3760 | } | |
3761 | ||
3762 | /* Omega expects the protected variables (those that have to be kept | |
3763 | after elimination) to appear first in the constraint system. | |
3764 | These variables are the distance variables. In the following | |
3765 | initialization we declare NB_LOOPS safe variables, and the total | |
3766 | number of variables for the constraint system is 2*NB_LOOPS. */ | |
3767 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
3768 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
3769 | maybe_dependent); | |
3770 | omega_free_problem (pb); | |
3771 | ||
3772 | /* Stop computation if not decidable, or no dependence. */ | |
3773 | if (res == false || *maybe_dependent == false) | |
3774 | return res; | |
3775 | ||
3776 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
3777 | res = init_omega_for_ddr_1 (DDR_B (ddr), DDR_A (ddr), ddr, pb, | |
3778 | maybe_dependent); | |
3779 | omega_free_problem (pb); | |
3780 | ||
3781 | return res; | |
3782 | } | |
3783 | ||
3784 | /* Return true when DDR contains the same information as that stored | |
3785 | in DIR_VECTS and in DIST_VECTS, return false otherwise. */ | |
3786 | ||
3787 | static bool | |
3788 | ddr_consistent_p (FILE *file, | |
3789 | struct data_dependence_relation *ddr, | |
3790 | VEC (lambda_vector, heap) *dist_vects, | |
3791 | VEC (lambda_vector, heap) *dir_vects) | |
3792 | { | |
3793 | unsigned int i, j; | |
3794 | ||
3795 | /* If dump_file is set, output there. */ | |
3796 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3797 | file = dump_file; | |
3798 | ||
3799 | if (VEC_length (lambda_vector, dist_vects) != DDR_NUM_DIST_VECTS (ddr)) | |
3800 | { | |
3801 | lambda_vector b_dist_v; | |
3802 | fprintf (file, "\n(Number of distance vectors differ: Banerjee has %d, Omega has %d.\n", | |
3803 | VEC_length (lambda_vector, dist_vects), | |
3804 | DDR_NUM_DIST_VECTS (ddr)); | |
3805 | ||
3806 | fprintf (file, "Banerjee dist vectors:\n"); | |
3807 | for (i = 0; VEC_iterate (lambda_vector, dist_vects, i, b_dist_v); i++) | |
3808 | print_lambda_vector (file, b_dist_v, DDR_NB_LOOPS (ddr)); | |
3809 | ||
3810 | fprintf (file, "Omega dist vectors:\n"); | |
3811 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3812 | print_lambda_vector (file, DDR_DIST_VECT (ddr, i), DDR_NB_LOOPS (ddr)); | |
3813 | ||
3814 | fprintf (file, "data dependence relation:\n"); | |
3815 | dump_data_dependence_relation (file, ddr); | |
3816 | ||
3817 | fprintf (file, ")\n"); | |
3818 | return false; | |
3819 | } | |
3820 | ||
3821 | if (VEC_length (lambda_vector, dir_vects) != DDR_NUM_DIR_VECTS (ddr)) | |
3822 | { | |
3823 | fprintf (file, "\n(Number of direction vectors differ: Banerjee has %d, Omega has %d.)\n", | |
3824 | VEC_length (lambda_vector, dir_vects), | |
3825 | DDR_NUM_DIR_VECTS (ddr)); | |
3826 | return false; | |
3827 | } | |
3828 | ||
3829 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3830 | { | |
3831 | lambda_vector a_dist_v; | |
3832 | lambda_vector b_dist_v = DDR_DIST_VECT (ddr, i); | |
3833 | ||
3834 | /* Distance vectors are not ordered in the same way in the DDR | |
3835 | and in the DIST_VECTS: search for a matching vector. */ | |
3836 | for (j = 0; VEC_iterate (lambda_vector, dist_vects, j, a_dist_v); j++) | |
3837 | if (lambda_vector_equal (a_dist_v, b_dist_v, DDR_NB_LOOPS (ddr))) | |
3838 | break; | |
3839 | ||
3840 | if (j == VEC_length (lambda_vector, dist_vects)) | |
3841 | { | |
3842 | fprintf (file, "\n(Dist vectors from the first dependence analyzer:\n"); | |
3843 | print_dist_vectors (file, dist_vects, DDR_NB_LOOPS (ddr)); | |
3844 | fprintf (file, "not found in Omega dist vectors:\n"); | |
3845 | print_dist_vectors (file, DDR_DIST_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
3846 | fprintf (file, "data dependence relation:\n"); | |
3847 | dump_data_dependence_relation (file, ddr); | |
3848 | fprintf (file, ")\n"); | |
3849 | } | |
3850 | } | |
3851 | ||
3852 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
3853 | { | |
3854 | lambda_vector a_dir_v; | |
3855 | lambda_vector b_dir_v = DDR_DIR_VECT (ddr, i); | |
3856 | ||
3857 | /* Direction vectors are not ordered in the same way in the DDR | |
3858 | and in the DIR_VECTS: search for a matching vector. */ | |
3859 | for (j = 0; VEC_iterate (lambda_vector, dir_vects, j, a_dir_v); j++) | |
3860 | if (lambda_vector_equal (a_dir_v, b_dir_v, DDR_NB_LOOPS (ddr))) | |
3861 | break; | |
3862 | ||
3863 | if (j == VEC_length (lambda_vector, dist_vects)) | |
3864 | { | |
3865 | fprintf (file, "\n(Dir vectors from the first dependence analyzer:\n"); | |
3866 | print_dir_vectors (file, dir_vects, DDR_NB_LOOPS (ddr)); | |
3867 | fprintf (file, "not found in Omega dir vectors:\n"); | |
3868 | print_dir_vectors (file, DDR_DIR_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
3869 | fprintf (file, "data dependence relation:\n"); | |
3870 | dump_data_dependence_relation (file, ddr); | |
3871 | fprintf (file, ")\n"); | |
3872 | } | |
3873 | } | |
3874 | ||
3875 | return true; | |
3876 | } | |
3877 | ||
da9a21f4 SP |
3878 | /* This computes the affine dependence relation between A and B with |
3879 | respect to LOOP_NEST. CHREC_KNOWN is used for representing the | |
3880 | independence between two accesses, while CHREC_DONT_KNOW is used | |
3881 | for representing the unknown relation. | |
56cf8686 SP |
3882 | |
3883 | Note that it is possible to stop the computation of the dependence | |
3884 | relation the first time we detect a CHREC_KNOWN element for a given | |
3885 | subscript. */ | |
3886 | ||
0ff4040e | 3887 | static void |
da9a21f4 SP |
3888 | compute_affine_dependence (struct data_dependence_relation *ddr, |
3889 | struct loop *loop_nest) | |
56cf8686 SP |
3890 | { |
3891 | struct data_reference *dra = DDR_A (ddr); | |
3892 | struct data_reference *drb = DDR_B (ddr); | |
3893 | ||
3894 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3895 | { | |
36d59cf7 | 3896 | fprintf (dump_file, "(compute_affine_dependence\n"); |
56cf8686 | 3897 | fprintf (dump_file, " (stmt_a = \n"); |
726a989a | 3898 | print_gimple_stmt (dump_file, DR_STMT (dra), 0, 0); |
56cf8686 | 3899 | fprintf (dump_file, ")\n (stmt_b = \n"); |
726a989a | 3900 | print_gimple_stmt (dump_file, DR_STMT (drb), 0, 0); |
56cf8686 SP |
3901 | fprintf (dump_file, ")\n"); |
3902 | } | |
0ff4040e | 3903 | |
56cf8686 | 3904 | /* Analyze only when the dependence relation is not yet known. */ |
b3924be9 SP |
3905 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE |
3906 | && !DDR_SELF_REFERENCE (ddr)) | |
56cf8686 | 3907 | { |
0ff4040e SP |
3908 | dependence_stats.num_dependence_tests++; |
3909 | ||
da9a21f4 SP |
3910 | if (access_functions_are_affine_or_constant_p (dra, loop_nest) |
3911 | && access_functions_are_affine_or_constant_p (drb, loop_nest)) | |
3d8864c0 SP |
3912 | { |
3913 | if (flag_check_data_deps) | |
3914 | { | |
3915 | /* Compute the dependences using the first algorithm. */ | |
da9a21f4 | 3916 | subscript_dependence_tester (ddr, loop_nest); |
3d8864c0 SP |
3917 | |
3918 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3919 | { | |
3920 | fprintf (dump_file, "\n\nBanerjee Analyzer\n"); | |
3921 | dump_data_dependence_relation (dump_file, ddr); | |
3922 | } | |
3923 | ||
3924 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
3925 | { | |
3926 | bool maybe_dependent; | |
3927 | VEC (lambda_vector, heap) *dir_vects, *dist_vects; | |
3928 | ||
3929 | /* Save the result of the first DD analyzer. */ | |
3930 | dist_vects = DDR_DIST_VECTS (ddr); | |
3931 | dir_vects = DDR_DIR_VECTS (ddr); | |
3932 | ||
3933 | /* Reset the information. */ | |
3934 | DDR_DIST_VECTS (ddr) = NULL; | |
3935 | DDR_DIR_VECTS (ddr) = NULL; | |
3936 | ||
3937 | /* Compute the same information using Omega. */ | |
3938 | if (!init_omega_for_ddr (ddr, &maybe_dependent)) | |
3939 | goto csys_dont_know; | |
3940 | ||
3941 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3942 | { | |
3943 | fprintf (dump_file, "Omega Analyzer\n"); | |
3944 | dump_data_dependence_relation (dump_file, ddr); | |
3945 | } | |
3946 | ||
3947 | /* Check that we get the same information. */ | |
3948 | if (maybe_dependent) | |
3949 | gcc_assert (ddr_consistent_p (stderr, ddr, dist_vects, | |
3950 | dir_vects)); | |
3951 | } | |
3952 | } | |
3953 | else | |
da9a21f4 | 3954 | subscript_dependence_tester (ddr, loop_nest); |
3d8864c0 SP |
3955 | } |
3956 | ||
56cf8686 SP |
3957 | /* As a last case, if the dependence cannot be determined, or if |
3958 | the dependence is considered too difficult to determine, answer | |
3959 | "don't know". */ | |
3960 | else | |
0ff4040e | 3961 | { |
3d8864c0 | 3962 | csys_dont_know:; |
0ff4040e SP |
3963 | dependence_stats.num_dependence_undetermined++; |
3964 | ||
3965 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3966 | { | |
3967 | fprintf (dump_file, "Data ref a:\n"); | |
3968 | dump_data_reference (dump_file, dra); | |
3969 | fprintf (dump_file, "Data ref b:\n"); | |
3970 | dump_data_reference (dump_file, drb); | |
3971 | fprintf (dump_file, "affine dependence test not usable: access function not affine or constant.\n"); | |
3972 | } | |
3973 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
3974 | } | |
56cf8686 SP |
3975 | } |
3976 | ||
3977 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3978 | fprintf (dump_file, ")\n"); | |
3979 | } | |
3980 | ||
789246d7 SP |
3981 | /* This computes the dependence relation for the same data |
3982 | reference into DDR. */ | |
3983 | ||
3984 | static void | |
3985 | compute_self_dependence (struct data_dependence_relation *ddr) | |
3986 | { | |
3987 | unsigned int i; | |
ebf78a47 | 3988 | struct subscript *subscript; |
789246d7 | 3989 | |
3cb960c7 ZD |
3990 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
3991 | return; | |
3992 | ||
ebf78a47 SP |
3993 | for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript); |
3994 | i++) | |
789246d7 | 3995 | { |
6935bae7 SP |
3996 | if (SUB_CONFLICTS_IN_A (subscript)) |
3997 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
3998 | if (SUB_CONFLICTS_IN_B (subscript)) | |
3999 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
4000 | ||
789246d7 | 4001 | /* The accessed index overlaps for each iteration. */ |
d93817c4 | 4002 | SUB_CONFLICTS_IN_A (subscript) |
6935bae7 | 4003 | = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
d93817c4 | 4004 | SUB_CONFLICTS_IN_B (subscript) |
6935bae7 | 4005 | = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
789246d7 SP |
4006 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
4007 | } | |
789246d7 | 4008 | |
0ff4040e | 4009 | /* The distance vector is the zero vector. */ |
ba42e045 SP |
4010 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); |
4011 | save_dir_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
0ff4040e | 4012 | } |
7b8a92e1 | 4013 | |
ba42e045 SP |
4014 | /* Compute in DEPENDENCE_RELATIONS the data dependence graph for all |
4015 | the data references in DATAREFS, in the LOOP_NEST. When | |
ebf78a47 SP |
4016 | COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self |
4017 | relations. */ | |
56cf8686 | 4018 | |
5417e022 | 4019 | void |
ebf78a47 | 4020 | compute_all_dependences (VEC (data_reference_p, heap) *datarefs, |
a84481aa | 4021 | VEC (ddr_p, heap) **dependence_relations, |
ba42e045 | 4022 | VEC (loop_p, heap) *loop_nest, |
ebf78a47 | 4023 | bool compute_self_and_rr) |
56cf8686 | 4024 | { |
ebf78a47 SP |
4025 | struct data_dependence_relation *ddr; |
4026 | struct data_reference *a, *b; | |
4027 | unsigned int i, j; | |
56cf8686 | 4028 | |
ebf78a47 SP |
4029 | for (i = 0; VEC_iterate (data_reference_p, datarefs, i, a); i++) |
4030 | for (j = i + 1; VEC_iterate (data_reference_p, datarefs, j, b); j++) | |
4031 | if (!DR_IS_READ (a) || !DR_IS_READ (b) || compute_self_and_rr) | |
4032 | { | |
4033 | ddr = initialize_data_dependence_relation (a, b, loop_nest); | |
a84481aa | 4034 | VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); |
a70d6342 IR |
4035 | if (loop_nest) |
4036 | compute_affine_dependence (ddr, VEC_index (loop_p, loop_nest, 0)); | |
ebf78a47 | 4037 | } |
789246d7 | 4038 | |
ebf78a47 SP |
4039 | if (compute_self_and_rr) |
4040 | for (i = 0; VEC_iterate (data_reference_p, datarefs, i, a); i++) | |
56cf8686 | 4041 | { |
ebf78a47 | 4042 | ddr = initialize_data_dependence_relation (a, a, loop_nest); |
a84481aa | 4043 | VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); |
ebf78a47 | 4044 | compute_self_dependence (ddr); |
56cf8686 SP |
4045 | } |
4046 | } | |
4047 | ||
946e1bc7 ZD |
4048 | /* Stores the locations of memory references in STMT to REFERENCES. Returns |
4049 | true if STMT clobbers memory, false otherwise. */ | |
4050 | ||
4051 | bool | |
726a989a | 4052 | get_references_in_stmt (gimple stmt, VEC (data_ref_loc, heap) **references) |
946e1bc7 ZD |
4053 | { |
4054 | bool clobbers_memory = false; | |
4055 | data_ref_loc *ref; | |
726a989a RB |
4056 | tree *op0, *op1; |
4057 | enum gimple_code stmt_code = gimple_code (stmt); | |
946e1bc7 ZD |
4058 | |
4059 | *references = NULL; | |
4060 | ||
4061 | /* ASM_EXPR and CALL_EXPR may embed arbitrary side effects. | |
4062 | Calls have side-effects, except those to const or pure | |
4063 | functions. */ | |
726a989a RB |
4064 | if ((stmt_code == GIMPLE_CALL |
4065 | && !(gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE))) | |
4066 | || (stmt_code == GIMPLE_ASM | |
4067 | && gimple_asm_volatile_p (stmt))) | |
946e1bc7 ZD |
4068 | clobbers_memory = true; |
4069 | ||
5006671f | 4070 | if (!gimple_vuse (stmt)) |
946e1bc7 ZD |
4071 | return clobbers_memory; |
4072 | ||
726a989a | 4073 | if (stmt_code == GIMPLE_ASSIGN) |
946e1bc7 | 4074 | { |
c8ae0bec | 4075 | tree base; |
726a989a RB |
4076 | op0 = gimple_assign_lhs_ptr (stmt); |
4077 | op1 = gimple_assign_rhs1_ptr (stmt); | |
946e1bc7 ZD |
4078 | |
4079 | if (DECL_P (*op1) | |
c8ae0bec RG |
4080 | || (REFERENCE_CLASS_P (*op1) |
4081 | && (base = get_base_address (*op1)) | |
4082 | && TREE_CODE (base) != SSA_NAME)) | |
946e1bc7 ZD |
4083 | { |
4084 | ref = VEC_safe_push (data_ref_loc, heap, *references, NULL); | |
4085 | ref->pos = op1; | |
4086 | ref->is_read = true; | |
4087 | } | |
4088 | ||
4089 | if (DECL_P (*op0) | |
0976ffb6 | 4090 | || (REFERENCE_CLASS_P (*op0) && get_base_address (*op0))) |
946e1bc7 ZD |
4091 | { |
4092 | ref = VEC_safe_push (data_ref_loc, heap, *references, NULL); | |
4093 | ref->pos = op0; | |
4094 | ref->is_read = false; | |
4095 | } | |
4096 | } | |
726a989a | 4097 | else if (stmt_code == GIMPLE_CALL) |
946e1bc7 | 4098 | { |
726a989a | 4099 | unsigned i, n = gimple_call_num_args (stmt); |
ac84e05e ZD |
4100 | |
4101 | for (i = 0; i < n; i++) | |
946e1bc7 | 4102 | { |
726a989a | 4103 | op0 = gimple_call_arg_ptr (stmt, i); |
ac84e05e | 4104 | |
946e1bc7 | 4105 | if (DECL_P (*op0) |
0976ffb6 | 4106 | || (REFERENCE_CLASS_P (*op0) && get_base_address (*op0))) |
946e1bc7 ZD |
4107 | { |
4108 | ref = VEC_safe_push (data_ref_loc, heap, *references, NULL); | |
4109 | ref->pos = op0; | |
4110 | ref->is_read = true; | |
4111 | } | |
4112 | } | |
4113 | } | |
4114 | ||
4115 | return clobbers_memory; | |
4116 | } | |
4117 | ||
4118 | /* Stores the data references in STMT to DATAREFS. If there is an unanalyzable | |
3cb960c7 | 4119 | reference, returns false, otherwise returns true. NEST is the outermost |
f8bf9252 | 4120 | loop of the loop nest in which the references should be analyzed. */ |
946e1bc7 | 4121 | |
f8bf9252 | 4122 | bool |
726a989a | 4123 | find_data_references_in_stmt (struct loop *nest, gimple stmt, |
946e1bc7 ZD |
4124 | VEC (data_reference_p, heap) **datarefs) |
4125 | { | |
4126 | unsigned i; | |
4127 | VEC (data_ref_loc, heap) *references; | |
4128 | data_ref_loc *ref; | |
4129 | bool ret = true; | |
4130 | data_reference_p dr; | |
4131 | ||
4132 | if (get_references_in_stmt (stmt, &references)) | |
4133 | { | |
4134 | VEC_free (data_ref_loc, heap, references); | |
4135 | return false; | |
4136 | } | |
4137 | ||
4138 | for (i = 0; VEC_iterate (data_ref_loc, references, i, ref); i++) | |
4139 | { | |
3cb960c7 | 4140 | dr = create_data_ref (nest, *ref->pos, stmt, ref->is_read); |
bbc8a8dc ZD |
4141 | gcc_assert (dr != NULL); |
4142 | ||
a70d6342 IR |
4143 | /* FIXME -- data dependence analysis does not work correctly for objects |
4144 | with invariant addresses in loop nests. Let us fail here until the | |
4145 | problem is fixed. */ | |
4146 | if (dr_address_invariant_p (dr) && nest) | |
946e1bc7 | 4147 | { |
bbc8a8dc ZD |
4148 | free_data_ref (dr); |
4149 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4150 | fprintf (dump_file, "\tFAILED as dr address is invariant\n"); | |
946e1bc7 ZD |
4151 | ret = false; |
4152 | break; | |
4153 | } | |
bbc8a8dc ZD |
4154 | |
4155 | VEC_safe_push (data_reference_p, heap, *datarefs, dr); | |
946e1bc7 ZD |
4156 | } |
4157 | VEC_free (data_ref_loc, heap, references); | |
4158 | return ret; | |
4159 | } | |
4160 | ||
a70d6342 IR |
4161 | /* Search the data references in LOOP, and record the information into |
4162 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4163 | difficult case, returns NULL_TREE otherwise. */ | |
4164 | ||
4165 | static tree | |
4166 | find_data_references_in_bb (struct loop *loop, basic_block bb, | |
4167 | VEC (data_reference_p, heap) **datarefs) | |
4168 | { | |
4169 | gimple_stmt_iterator bsi; | |
4170 | ||
4171 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
4172 | { | |
4173 | gimple stmt = gsi_stmt (bsi); | |
4174 | ||
4175 | if (!find_data_references_in_stmt (loop, stmt, datarefs)) | |
4176 | { | |
4177 | struct data_reference *res; | |
4178 | res = XCNEW (struct data_reference); | |
4179 | VEC_safe_push (data_reference_p, heap, *datarefs, res); | |
4180 | ||
4181 | return chrec_dont_know; | |
4182 | } | |
4183 | } | |
4184 | ||
4185 | return NULL_TREE; | |
4186 | } | |
4187 | ||
56cf8686 SP |
4188 | /* Search the data references in LOOP, and record the information into |
4189 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4190 | difficult case, returns NULL_TREE otherwise. | |
3cb960c7 | 4191 | |
464f49d8 DB |
4192 | TODO: This function should be made smarter so that it can handle address |
4193 | arithmetic as if they were array accesses, etc. */ | |
56cf8686 | 4194 | |
f8bf9252 | 4195 | tree |
ebf78a47 | 4196 | find_data_references_in_loop (struct loop *loop, |
e14b10df | 4197 | VEC (data_reference_p, heap) **datarefs) |
56cf8686 | 4198 | { |
ccbdbf0a JL |
4199 | basic_block bb, *bbs; |
4200 | unsigned int i; | |
86df10e3 | 4201 | |
bbc8a8dc | 4202 | bbs = get_loop_body_in_dom_order (loop); |
ccbdbf0a JL |
4203 | |
4204 | for (i = 0; i < loop->num_nodes; i++) | |
56cf8686 | 4205 | { |
ccbdbf0a JL |
4206 | bb = bbs[i]; |
4207 | ||
a70d6342 IR |
4208 | if (find_data_references_in_bb (loop, bb, datarefs) == chrec_dont_know) |
4209 | { | |
4210 | free (bbs); | |
4211 | return chrec_dont_know; | |
4212 | } | |
56cf8686 | 4213 | } |
ccbdbf0a JL |
4214 | free (bbs); |
4215 | ||
4aad410d | 4216 | return NULL_TREE; |
56cf8686 SP |
4217 | } |
4218 | ||
ba42e045 SP |
4219 | /* Recursive helper function. */ |
4220 | ||
4221 | static bool | |
3ac57120 | 4222 | find_loop_nest_1 (struct loop *loop, VEC (loop_p, heap) **loop_nest) |
ba42e045 SP |
4223 | { |
4224 | /* Inner loops of the nest should not contain siblings. Example: | |
4225 | when there are two consecutive loops, | |
4226 | ||
4227 | | loop_0 | |
4228 | | loop_1 | |
4229 | | A[{0, +, 1}_1] | |
4230 | | endloop_1 | |
4231 | | loop_2 | |
4232 | | A[{0, +, 1}_2] | |
4233 | | endloop_2 | |
4234 | | endloop_0 | |
4235 | ||
4236 | the dependence relation cannot be captured by the distance | |
4237 | abstraction. */ | |
4238 | if (loop->next) | |
4239 | return false; | |
56cf8686 | 4240 | |
3ac57120 | 4241 | VEC_safe_push (loop_p, heap, *loop_nest, loop); |
ba42e045 SP |
4242 | if (loop->inner) |
4243 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4244 | return true; | |
4245 | } | |
4246 | ||
4247 | /* Return false when the LOOP is not well nested. Otherwise return | |
4248 | true and insert in LOOP_NEST the loops of the nest. LOOP_NEST will | |
4249 | contain the loops from the outermost to the innermost, as they will | |
4250 | appear in the classic distance vector. */ | |
4251 | ||
5417e022 | 4252 | bool |
3ac57120 | 4253 | find_loop_nest (struct loop *loop, VEC (loop_p, heap) **loop_nest) |
ba42e045 | 4254 | { |
3ac57120 | 4255 | VEC_safe_push (loop_p, heap, *loop_nest, loop); |
ba42e045 SP |
4256 | if (loop->inner) |
4257 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4258 | return true; | |
4259 | } | |
56cf8686 | 4260 | |
9f275479 JS |
4261 | /* Returns true when the data dependences have been computed, false otherwise. |
4262 | Given a loop nest LOOP, the following vectors are returned: | |
ebf78a47 SP |
4263 | DATAREFS is initialized to all the array elements contained in this loop, |
4264 | DEPENDENCE_RELATIONS contains the relations between the data references. | |
86a07404 IR |
4265 | Compute read-read and self relations if |
4266 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ | |
56cf8686 | 4267 | |
9f275479 | 4268 | bool |
86a07404 IR |
4269 | compute_data_dependences_for_loop (struct loop *loop, |
4270 | bool compute_self_and_read_read_dependences, | |
e14b10df SP |
4271 | VEC (data_reference_p, heap) **datarefs, |
4272 | VEC (ddr_p, heap) **dependence_relations) | |
56cf8686 | 4273 | { |
9f275479 | 4274 | bool res = true; |
ba42e045 | 4275 | VEC (loop_p, heap) *vloops = VEC_alloc (loop_p, heap, 3); |
86a07404 | 4276 | |
0ff4040e | 4277 | memset (&dependence_stats, 0, sizeof (dependence_stats)); |
56cf8686 | 4278 | |
ba42e045 SP |
4279 | /* If the loop nest is not well formed, or one of the data references |
4280 | is not computable, give up without spending time to compute other | |
4281 | dependences. */ | |
3cb960c7 ZD |
4282 | if (!loop |
4283 | || !find_loop_nest (loop, &vloops) | |
ba42e045 | 4284 | || find_data_references_in_loop (loop, datarefs) == chrec_dont_know) |
56cf8686 SP |
4285 | { |
4286 | struct data_dependence_relation *ddr; | |
4287 | ||
4288 | /* Insert a single relation into dependence_relations: | |
4289 | chrec_dont_know. */ | |
ba42e045 | 4290 | ddr = initialize_data_dependence_relation (NULL, NULL, vloops); |
e14b10df | 4291 | VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); |
9f275479 | 4292 | res = false; |
56cf8686 | 4293 | } |
ba42e045 | 4294 | else |
a84481aa | 4295 | compute_all_dependences (*datarefs, dependence_relations, vloops, |
ebf78a47 | 4296 | compute_self_and_read_read_dependences); |
0ff4040e SP |
4297 | |
4298 | if (dump_file && (dump_flags & TDF_STATS)) | |
56cf8686 | 4299 | { |
0ff4040e SP |
4300 | fprintf (dump_file, "Dependence tester statistics:\n"); |
4301 | ||
4302 | fprintf (dump_file, "Number of dependence tests: %d\n", | |
4303 | dependence_stats.num_dependence_tests); | |
4304 | fprintf (dump_file, "Number of dependence tests classified dependent: %d\n", | |
4305 | dependence_stats.num_dependence_dependent); | |
4306 | fprintf (dump_file, "Number of dependence tests classified independent: %d\n", | |
4307 | dependence_stats.num_dependence_independent); | |
4308 | fprintf (dump_file, "Number of undetermined dependence tests: %d\n", | |
4309 | dependence_stats.num_dependence_undetermined); | |
4310 | ||
4311 | fprintf (dump_file, "Number of subscript tests: %d\n", | |
4312 | dependence_stats.num_subscript_tests); | |
4313 | fprintf (dump_file, "Number of undetermined subscript tests: %d\n", | |
4314 | dependence_stats.num_subscript_undetermined); | |
4315 | fprintf (dump_file, "Number of same subscript function: %d\n", | |
4316 | dependence_stats.num_same_subscript_function); | |
4317 | ||
4318 | fprintf (dump_file, "Number of ziv tests: %d\n", | |
4319 | dependence_stats.num_ziv); | |
4320 | fprintf (dump_file, "Number of ziv tests returning dependent: %d\n", | |
4321 | dependence_stats.num_ziv_dependent); | |
4322 | fprintf (dump_file, "Number of ziv tests returning independent: %d\n", | |
4323 | dependence_stats.num_ziv_independent); | |
4324 | fprintf (dump_file, "Number of ziv tests unimplemented: %d\n", | |
4325 | dependence_stats.num_ziv_unimplemented); | |
4326 | ||
4327 | fprintf (dump_file, "Number of siv tests: %d\n", | |
4328 | dependence_stats.num_siv); | |
4329 | fprintf (dump_file, "Number of siv tests returning dependent: %d\n", | |
4330 | dependence_stats.num_siv_dependent); | |
4331 | fprintf (dump_file, "Number of siv tests returning independent: %d\n", | |
4332 | dependence_stats.num_siv_independent); | |
4333 | fprintf (dump_file, "Number of siv tests unimplemented: %d\n", | |
4334 | dependence_stats.num_siv_unimplemented); | |
4335 | ||
4336 | fprintf (dump_file, "Number of miv tests: %d\n", | |
4337 | dependence_stats.num_miv); | |
4338 | fprintf (dump_file, "Number of miv tests returning dependent: %d\n", | |
4339 | dependence_stats.num_miv_dependent); | |
4340 | fprintf (dump_file, "Number of miv tests returning independent: %d\n", | |
4341 | dependence_stats.num_miv_independent); | |
4342 | fprintf (dump_file, "Number of miv tests unimplemented: %d\n", | |
4343 | dependence_stats.num_miv_unimplemented); | |
9f275479 JS |
4344 | } |
4345 | ||
4346 | return res; | |
56cf8686 SP |
4347 | } |
4348 | ||
a70d6342 IR |
4349 | /* Returns true when the data dependences for the basic block BB have been |
4350 | computed, false otherwise. | |
4351 | DATAREFS is initialized to all the array elements contained in this basic | |
4352 | block, DEPENDENCE_RELATIONS contains the relations between the data | |
4353 | references. Compute read-read and self relations if | |
4354 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ | |
4355 | bool | |
4356 | compute_data_dependences_for_bb (basic_block bb, | |
4357 | bool compute_self_and_read_read_dependences, | |
4358 | VEC (data_reference_p, heap) **datarefs, | |
4359 | VEC (ddr_p, heap) **dependence_relations) | |
4360 | { | |
4361 | if (find_data_references_in_bb (NULL, bb, datarefs) == chrec_dont_know) | |
4362 | return false; | |
4363 | ||
4364 | compute_all_dependences (*datarefs, dependence_relations, NULL, | |
4365 | compute_self_and_read_read_dependences); | |
4366 | return true; | |
4367 | } | |
4368 | ||
56cf8686 | 4369 | /* Entry point (for testing only). Analyze all the data references |
3d8864c0 | 4370 | and the dependence relations in LOOP. |
56cf8686 SP |
4371 | |
4372 | The data references are computed first. | |
4373 | ||
4374 | A relation on these nodes is represented by a complete graph. Some | |
4375 | of the relations could be of no interest, thus the relations can be | |
4376 | computed on demand. | |
4377 | ||
4378 | In the following function we compute all the relations. This is | |
4379 | just a first implementation that is here for: | |
4380 | - for showing how to ask for the dependence relations, | |
4381 | - for the debugging the whole dependence graph, | |
4382 | - for the dejagnu testcases and maintenance. | |
4383 | ||
4384 | It is possible to ask only for a part of the graph, avoiding to | |
4385 | compute the whole dependence graph. The computed dependences are | |
4386 | stored in a knowledge base (KB) such that later queries don't | |
4387 | recompute the same information. The implementation of this KB is | |
4388 | transparent to the optimizer, and thus the KB can be changed with a | |
4389 | more efficient implementation, or the KB could be disabled. */ | |
0ff4040e | 4390 | static void |
3d8864c0 | 4391 | analyze_all_data_dependences (struct loop *loop) |
56cf8686 SP |
4392 | { |
4393 | unsigned int i; | |
56cf8686 | 4394 | int nb_data_refs = 10; |
ebf78a47 SP |
4395 | VEC (data_reference_p, heap) *datarefs = |
4396 | VEC_alloc (data_reference_p, heap, nb_data_refs); | |
4397 | VEC (ddr_p, heap) *dependence_relations = | |
4398 | VEC_alloc (ddr_p, heap, nb_data_refs * nb_data_refs); | |
56cf8686 SP |
4399 | |
4400 | /* Compute DDs on the whole function. */ | |
3d8864c0 SP |
4401 | compute_data_dependences_for_loop (loop, false, &datarefs, |
4402 | &dependence_relations); | |
56cf8686 SP |
4403 | |
4404 | if (dump_file) | |
4405 | { | |
4406 | dump_data_dependence_relations (dump_file, dependence_relations); | |
4407 | fprintf (dump_file, "\n\n"); | |
56cf8686 | 4408 | |
86df10e3 SP |
4409 | if (dump_flags & TDF_DETAILS) |
4410 | dump_dist_dir_vectors (dump_file, dependence_relations); | |
56cf8686 | 4411 | |
86df10e3 | 4412 | if (dump_flags & TDF_STATS) |
56cf8686 | 4413 | { |
86df10e3 SP |
4414 | unsigned nb_top_relations = 0; |
4415 | unsigned nb_bot_relations = 0; | |
86df10e3 | 4416 | unsigned nb_chrec_relations = 0; |
ebf78a47 | 4417 | struct data_dependence_relation *ddr; |
86df10e3 | 4418 | |
ebf78a47 | 4419 | for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++) |
86df10e3 | 4420 | { |
86df10e3 SP |
4421 | if (chrec_contains_undetermined (DDR_ARE_DEPENDENT (ddr))) |
4422 | nb_top_relations++; | |
56cf8686 | 4423 | |
86df10e3 | 4424 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
5006671f | 4425 | nb_bot_relations++; |
56cf8686 | 4426 | |
86df10e3 SP |
4427 | else |
4428 | nb_chrec_relations++; | |
4429 | } | |
56cf8686 | 4430 | |
86df10e3 SP |
4431 | gather_stats_on_scev_database (); |
4432 | } | |
56cf8686 | 4433 | } |
36d59cf7 DB |
4434 | |
4435 | free_dependence_relations (dependence_relations); | |
4436 | free_data_refs (datarefs); | |
4437 | } | |
3d8864c0 SP |
4438 | |
4439 | /* Computes all the data dependences and check that the results of | |
4440 | several analyzers are the same. */ | |
4441 | ||
4442 | void | |
4443 | tree_check_data_deps (void) | |
4444 | { | |
4445 | loop_iterator li; | |
4446 | struct loop *loop_nest; | |
4447 | ||
4448 | FOR_EACH_LOOP (li, loop_nest, 0) | |
4449 | analyze_all_data_dependences (loop_nest); | |
4450 | } | |
36d59cf7 DB |
4451 | |
4452 | /* Free the memory used by a data dependence relation DDR. */ | |
4453 | ||
4454 | void | |
4455 | free_dependence_relation (struct data_dependence_relation *ddr) | |
4456 | { | |
4457 | if (ddr == NULL) | |
4458 | return; | |
4459 | ||
2f470326 | 4460 | if (DDR_SUBSCRIPTS (ddr)) |
d93817c4 | 4461 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
2f470326 JJ |
4462 | if (DDR_DIST_VECTS (ddr)) |
4463 | VEC_free (lambda_vector, heap, DDR_DIST_VECTS (ddr)); | |
4464 | if (DDR_DIR_VECTS (ddr)) | |
4465 | VEC_free (lambda_vector, heap, DDR_DIR_VECTS (ddr)); | |
ebf78a47 | 4466 | |
36d59cf7 DB |
4467 | free (ddr); |
4468 | } | |
4469 | ||
4470 | /* Free the memory used by the data dependence relations from | |
4471 | DEPENDENCE_RELATIONS. */ | |
4472 | ||
4473 | void | |
ebf78a47 | 4474 | free_dependence_relations (VEC (ddr_p, heap) *dependence_relations) |
36d59cf7 DB |
4475 | { |
4476 | unsigned int i; | |
ebf78a47 | 4477 | struct data_dependence_relation *ddr; |
3ac57120 | 4478 | VEC (loop_p, heap) *loop_nest = NULL; |
36d59cf7 | 4479 | |
ebf78a47 | 4480 | for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++) |
3ac57120 JJ |
4481 | { |
4482 | if (ddr == NULL) | |
4483 | continue; | |
4484 | if (loop_nest == NULL) | |
4485 | loop_nest = DDR_LOOP_NEST (ddr); | |
4486 | else | |
4487 | gcc_assert (DDR_LOOP_NEST (ddr) == NULL | |
4488 | || DDR_LOOP_NEST (ddr) == loop_nest); | |
4489 | free_dependence_relation (ddr); | |
4490 | } | |
ebf78a47 | 4491 | |
3ac57120 JJ |
4492 | if (loop_nest) |
4493 | VEC_free (loop_p, heap, loop_nest); | |
ebf78a47 | 4494 | VEC_free (ddr_p, heap, dependence_relations); |
56cf8686 SP |
4495 | } |
4496 | ||
36d59cf7 DB |
4497 | /* Free the memory used by the data references from DATAREFS. */ |
4498 | ||
4499 | void | |
ebf78a47 | 4500 | free_data_refs (VEC (data_reference_p, heap) *datarefs) |
36d59cf7 DB |
4501 | { |
4502 | unsigned int i; | |
ebf78a47 | 4503 | struct data_reference *dr; |
56cf8686 | 4504 | |
ebf78a47 | 4505 | for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++) |
8fdbc9c6 | 4506 | free_data_ref (dr); |
ebf78a47 | 4507 | VEC_free (data_reference_p, heap, datarefs); |
36d59cf7 | 4508 | } |
86df10e3 | 4509 | |
3a796c6f SP |
4510 | \f |
4511 | ||
dea61d92 | 4512 | /* Dump vertex I in RDG to FILE. */ |
3a796c6f | 4513 | |
dea61d92 SP |
4514 | void |
4515 | dump_rdg_vertex (FILE *file, struct graph *rdg, int i) | |
4516 | { | |
4517 | struct vertex *v = &(rdg->vertices[i]); | |
4518 | struct graph_edge *e; | |
4519 | ||
4520 | fprintf (file, "(vertex %d: (%s%s) (in:", i, | |
4521 | RDG_MEM_WRITE_STMT (rdg, i) ? "w" : "", | |
4522 | RDG_MEM_READS_STMT (rdg, i) ? "r" : ""); | |
4523 | ||
4524 | if (v->pred) | |
4525 | for (e = v->pred; e; e = e->pred_next) | |
4526 | fprintf (file, " %d", e->src); | |
4527 | ||
4528 | fprintf (file, ") (out:"); | |
4529 | ||
4530 | if (v->succ) | |
4531 | for (e = v->succ; e; e = e->succ_next) | |
4532 | fprintf (file, " %d", e->dest); | |
4533 | ||
4534 | fprintf (file, ") \n"); | |
726a989a | 4535 | print_gimple_stmt (file, RDGV_STMT (v), 0, TDF_VOPS|TDF_MEMSYMS); |
dea61d92 SP |
4536 | fprintf (file, ")\n"); |
4537 | } | |
4538 | ||
4539 | /* Call dump_rdg_vertex on stderr. */ | |
4540 | ||
4541 | void | |
4542 | debug_rdg_vertex (struct graph *rdg, int i) | |
4543 | { | |
4544 | dump_rdg_vertex (stderr, rdg, i); | |
4545 | } | |
4546 | ||
4547 | /* Dump component C of RDG to FILE. If DUMPED is non-null, set the | |
4548 | dumped vertices to that bitmap. */ | |
4549 | ||
4550 | void dump_rdg_component (FILE *file, struct graph *rdg, int c, bitmap dumped) | |
4551 | { | |
4552 | int i; | |
4553 | ||
4554 | fprintf (file, "(%d\n", c); | |
4555 | ||
4556 | for (i = 0; i < rdg->n_vertices; i++) | |
4557 | if (rdg->vertices[i].component == c) | |
4558 | { | |
4559 | if (dumped) | |
4560 | bitmap_set_bit (dumped, i); | |
4561 | ||
4562 | dump_rdg_vertex (file, rdg, i); | |
4563 | } | |
4564 | ||
4565 | fprintf (file, ")\n"); | |
4566 | } | |
4567 | ||
4568 | /* Call dump_rdg_vertex on stderr. */ | |
4569 | ||
4570 | void | |
4571 | debug_rdg_component (struct graph *rdg, int c) | |
4572 | { | |
4573 | dump_rdg_component (stderr, rdg, c, NULL); | |
4574 | } | |
4575 | ||
4576 | /* Dump the reduced dependence graph RDG to FILE. */ | |
4577 | ||
4578 | void | |
4579 | dump_rdg (FILE *file, struct graph *rdg) | |
3a796c6f SP |
4580 | { |
4581 | int i; | |
dea61d92 SP |
4582 | bitmap dumped = BITMAP_ALLOC (NULL); |
4583 | ||
4584 | fprintf (file, "(rdg\n"); | |
3a796c6f SP |
4585 | |
4586 | for (i = 0; i < rdg->n_vertices; i++) | |
dea61d92 SP |
4587 | if (!bitmap_bit_p (dumped, i)) |
4588 | dump_rdg_component (file, rdg, rdg->vertices[i].component, dumped); | |
3a796c6f | 4589 | |
dea61d92 SP |
4590 | fprintf (file, ")\n"); |
4591 | BITMAP_FREE (dumped); | |
3a796c6f SP |
4592 | } |
4593 | ||
dea61d92 SP |
4594 | /* Call dump_rdg on stderr. */ |
4595 | ||
4596 | void | |
4597 | debug_rdg (struct graph *rdg) | |
4598 | { | |
4599 | dump_rdg (stderr, rdg); | |
4600 | } | |
3a796c6f SP |
4601 | |
4602 | static void | |
dea61d92 | 4603 | dot_rdg_1 (FILE *file, struct graph *rdg) |
3a796c6f | 4604 | { |
dea61d92 SP |
4605 | int i; |
4606 | ||
4607 | fprintf (file, "digraph RDG {\n"); | |
3a796c6f | 4608 | |
dea61d92 | 4609 | for (i = 0; i < rdg->n_vertices; i++) |
3a796c6f | 4610 | { |
dea61d92 SP |
4611 | struct vertex *v = &(rdg->vertices[i]); |
4612 | struct graph_edge *e; | |
4613 | ||
4614 | /* Highlight reads from memory. */ | |
4615 | if (RDG_MEM_READS_STMT (rdg, i)) | |
4616 | fprintf (file, "%d [style=filled, fillcolor=green]\n", i); | |
4617 | ||
4618 | /* Highlight stores to memory. */ | |
4619 | if (RDG_MEM_WRITE_STMT (rdg, i)) | |
4620 | fprintf (file, "%d [style=filled, fillcolor=red]\n", i); | |
4621 | ||
4622 | if (v->succ) | |
4623 | for (e = v->succ; e; e = e->succ_next) | |
4624 | switch (RDGE_TYPE (e)) | |
4625 | { | |
4626 | case input_dd: | |
4627 | fprintf (file, "%d -> %d [label=input] \n", i, e->dest); | |
4628 | break; | |
4629 | ||
4630 | case output_dd: | |
4631 | fprintf (file, "%d -> %d [label=output] \n", i, e->dest); | |
4632 | break; | |
4633 | ||
4634 | case flow_dd: | |
4635 | /* These are the most common dependences: don't print these. */ | |
4636 | fprintf (file, "%d -> %d \n", i, e->dest); | |
4637 | break; | |
4638 | ||
4639 | case anti_dd: | |
4640 | fprintf (file, "%d -> %d [label=anti] \n", i, e->dest); | |
4641 | break; | |
4642 | ||
4643 | default: | |
4644 | gcc_unreachable (); | |
4645 | } | |
3a796c6f | 4646 | } |
dea61d92 SP |
4647 | |
4648 | fprintf (file, "}\n\n"); | |
4649 | } | |
4650 | ||
4651 | /* Display SCOP using dotty. */ | |
4652 | ||
4653 | void | |
4654 | dot_rdg (struct graph *rdg) | |
4655 | { | |
4656 | FILE *file = fopen ("/tmp/rdg.dot", "w"); | |
4657 | gcc_assert (file != NULL); | |
4658 | ||
4659 | dot_rdg_1 (file, rdg); | |
4660 | fclose (file); | |
4661 | ||
4662 | system ("dotty /tmp/rdg.dot"); | |
4663 | } | |
4664 | ||
4665 | ||
4666 | /* This structure is used for recording the mapping statement index in | |
4667 | the RDG. */ | |
4668 | ||
d1b38208 | 4669 | struct GTY(()) rdg_vertex_info |
dea61d92 | 4670 | { |
726a989a | 4671 | gimple stmt; |
dea61d92 SP |
4672 | int index; |
4673 | }; | |
4674 | ||
4675 | /* Returns the index of STMT in RDG. */ | |
4676 | ||
4677 | int | |
726a989a | 4678 | rdg_vertex_for_stmt (struct graph *rdg, gimple stmt) |
dea61d92 SP |
4679 | { |
4680 | struct rdg_vertex_info rvi, *slot; | |
4681 | ||
4682 | rvi.stmt = stmt; | |
4683 | slot = (struct rdg_vertex_info *) htab_find (rdg->indices, &rvi); | |
4684 | ||
4685 | if (!slot) | |
4686 | return -1; | |
4687 | ||
4688 | return slot->index; | |
4689 | } | |
4690 | ||
4691 | /* Creates an edge in RDG for each distance vector from DDR. The | |
4692 | order that we keep track of in the RDG is the order in which | |
4693 | statements have to be executed. */ | |
4694 | ||
4695 | static void | |
4696 | create_rdg_edge_for_ddr (struct graph *rdg, ddr_p ddr) | |
4697 | { | |
4698 | struct graph_edge *e; | |
4699 | int va, vb; | |
4700 | data_reference_p dra = DDR_A (ddr); | |
4701 | data_reference_p drb = DDR_B (ddr); | |
4702 | unsigned level = ddr_dependence_level (ddr); | |
4703 | ||
4704 | /* For non scalar dependences, when the dependence is REVERSED, | |
4705 | statement B has to be executed before statement A. */ | |
4706 | if (level > 0 | |
4707 | && !DDR_REVERSED_P (ddr)) | |
3a796c6f | 4708 | { |
dea61d92 SP |
4709 | data_reference_p tmp = dra; |
4710 | dra = drb; | |
4711 | drb = tmp; | |
3a796c6f SP |
4712 | } |
4713 | ||
dea61d92 SP |
4714 | va = rdg_vertex_for_stmt (rdg, DR_STMT (dra)); |
4715 | vb = rdg_vertex_for_stmt (rdg, DR_STMT (drb)); | |
4716 | ||
4717 | if (va < 0 || vb < 0) | |
4718 | return; | |
3a796c6f SP |
4719 | |
4720 | e = add_edge (rdg, va, vb); | |
4721 | e->data = XNEW (struct rdg_edge); | |
4722 | ||
dea61d92 | 4723 | RDGE_LEVEL (e) = level; |
f8bf9252 | 4724 | RDGE_RELATION (e) = ddr; |
dea61d92 | 4725 | |
3a796c6f SP |
4726 | /* Determines the type of the data dependence. */ |
4727 | if (DR_IS_READ (dra) && DR_IS_READ (drb)) | |
4728 | RDGE_TYPE (e) = input_dd; | |
4729 | else if (!DR_IS_READ (dra) && !DR_IS_READ (drb)) | |
4730 | RDGE_TYPE (e) = output_dd; | |
4731 | else if (!DR_IS_READ (dra) && DR_IS_READ (drb)) | |
4732 | RDGE_TYPE (e) = flow_dd; | |
4733 | else if (DR_IS_READ (dra) && !DR_IS_READ (drb)) | |
4734 | RDGE_TYPE (e) = anti_dd; | |
4735 | } | |
4736 | ||
4737 | /* Creates dependence edges in RDG for all the uses of DEF. IDEF is | |
4738 | the index of DEF in RDG. */ | |
4739 | ||
4740 | static void | |
4741 | create_rdg_edges_for_scalar (struct graph *rdg, tree def, int idef) | |
4742 | { | |
4743 | use_operand_p imm_use_p; | |
4744 | imm_use_iterator iterator; | |
4745 | ||
4746 | FOR_EACH_IMM_USE_FAST (imm_use_p, iterator, def) | |
4747 | { | |
dea61d92 SP |
4748 | struct graph_edge *e; |
4749 | int use = rdg_vertex_for_stmt (rdg, USE_STMT (imm_use_p)); | |
3a796c6f | 4750 | |
dea61d92 SP |
4751 | if (use < 0) |
4752 | continue; | |
4753 | ||
4754 | e = add_edge (rdg, idef, use); | |
3a796c6f SP |
4755 | e->data = XNEW (struct rdg_edge); |
4756 | RDGE_TYPE (e) = flow_dd; | |
f8bf9252 | 4757 | RDGE_RELATION (e) = NULL; |
3a796c6f SP |
4758 | } |
4759 | } | |
4760 | ||
4761 | /* Creates the edges of the reduced dependence graph RDG. */ | |
4762 | ||
4763 | static void | |
4764 | create_rdg_edges (struct graph *rdg, VEC (ddr_p, heap) *ddrs) | |
4765 | { | |
4766 | int i; | |
4767 | struct data_dependence_relation *ddr; | |
4768 | def_operand_p def_p; | |
4769 | ssa_op_iter iter; | |
4770 | ||
4771 | for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) | |
4772 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
4773 | create_rdg_edge_for_ddr (rdg, ddr); | |
4774 | ||
4775 | for (i = 0; i < rdg->n_vertices; i++) | |
dea61d92 SP |
4776 | FOR_EACH_PHI_OR_STMT_DEF (def_p, RDG_STMT (rdg, i), |
4777 | iter, SSA_OP_DEF) | |
3a796c6f SP |
4778 | create_rdg_edges_for_scalar (rdg, DEF_FROM_PTR (def_p), i); |
4779 | } | |
4780 | ||
4781 | /* Build the vertices of the reduced dependence graph RDG. */ | |
4782 | ||
f8bf9252 | 4783 | void |
726a989a | 4784 | create_rdg_vertices (struct graph *rdg, VEC (gimple, heap) *stmts) |
3a796c6f | 4785 | { |
dea61d92 | 4786 | int i, j; |
726a989a | 4787 | gimple stmt; |
3a796c6f | 4788 | |
726a989a | 4789 | for (i = 0; VEC_iterate (gimple, stmts, i, stmt); i++) |
3a796c6f | 4790 | { |
dea61d92 SP |
4791 | VEC (data_ref_loc, heap) *references; |
4792 | data_ref_loc *ref; | |
3a796c6f | 4793 | struct vertex *v = &(rdg->vertices[i]); |
dea61d92 SP |
4794 | struct rdg_vertex_info *rvi = XNEW (struct rdg_vertex_info); |
4795 | struct rdg_vertex_info **slot; | |
4796 | ||
4797 | rvi->stmt = stmt; | |
4798 | rvi->index = i; | |
4799 | slot = (struct rdg_vertex_info **) htab_find_slot (rdg->indices, rvi, INSERT); | |
4800 | ||
4801 | if (!*slot) | |
4802 | *slot = rvi; | |
4803 | else | |
4804 | free (rvi); | |
3a796c6f SP |
4805 | |
4806 | v->data = XNEW (struct rdg_vertex); | |
dea61d92 SP |
4807 | RDG_STMT (rdg, i) = stmt; |
4808 | ||
4809 | RDG_MEM_WRITE_STMT (rdg, i) = false; | |
4810 | RDG_MEM_READS_STMT (rdg, i) = false; | |
726a989a | 4811 | if (gimple_code (stmt) == GIMPLE_PHI) |
dea61d92 SP |
4812 | continue; |
4813 | ||
4814 | get_references_in_stmt (stmt, &references); | |
4815 | for (j = 0; VEC_iterate (data_ref_loc, references, j, ref); j++) | |
4816 | if (!ref->is_read) | |
4817 | RDG_MEM_WRITE_STMT (rdg, i) = true; | |
4818 | else | |
4819 | RDG_MEM_READS_STMT (rdg, i) = true; | |
4820 | ||
4821 | VEC_free (data_ref_loc, heap, references); | |
3a796c6f SP |
4822 | } |
4823 | } | |
4824 | ||
dea61d92 SP |
4825 | /* Initialize STMTS with all the statements of LOOP. When |
4826 | INCLUDE_PHIS is true, include also the PHI nodes. The order in | |
4827 | which we discover statements is important as | |
4828 | generate_loops_for_partition is using the same traversal for | |
4829 | identifying statements. */ | |
3a796c6f SP |
4830 | |
4831 | static void | |
726a989a | 4832 | stmts_from_loop (struct loop *loop, VEC (gimple, heap) **stmts) |
3a796c6f SP |
4833 | { |
4834 | unsigned int i; | |
4835 | basic_block *bbs = get_loop_body_in_dom_order (loop); | |
4836 | ||
4837 | for (i = 0; i < loop->num_nodes; i++) | |
4838 | { | |
3a796c6f | 4839 | basic_block bb = bbs[i]; |
726a989a RB |
4840 | gimple_stmt_iterator bsi; |
4841 | gimple stmt; | |
3a796c6f | 4842 | |
726a989a RB |
4843 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
4844 | VEC_safe_push (gimple, heap, *stmts, gsi_stmt (bsi)); | |
3a796c6f | 4845 | |
726a989a RB |
4846 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
4847 | { | |
4848 | stmt = gsi_stmt (bsi); | |
4849 | if (gimple_code (stmt) != GIMPLE_LABEL) | |
4850 | VEC_safe_push (gimple, heap, *stmts, stmt); | |
4851 | } | |
3a796c6f SP |
4852 | } |
4853 | ||
4854 | free (bbs); | |
4855 | } | |
4856 | ||
4857 | /* Returns true when all the dependences are computable. */ | |
4858 | ||
4859 | static bool | |
4860 | known_dependences_p (VEC (ddr_p, heap) *dependence_relations) | |
4861 | { | |
4862 | ddr_p ddr; | |
4863 | unsigned int i; | |
4864 | ||
4865 | for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++) | |
4866 | if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) | |
4867 | return false; | |
4868 | ||
4869 | return true; | |
4870 | } | |
4871 | ||
dea61d92 SP |
4872 | /* Computes a hash function for element ELT. */ |
4873 | ||
4874 | static hashval_t | |
4875 | hash_stmt_vertex_info (const void *elt) | |
4876 | { | |
1634b18f KG |
4877 | const struct rdg_vertex_info *const rvi = |
4878 | (const struct rdg_vertex_info *) elt; | |
726a989a | 4879 | gimple stmt = rvi->stmt; |
dea61d92 SP |
4880 | |
4881 | return htab_hash_pointer (stmt); | |
4882 | } | |
4883 | ||
4884 | /* Compares database elements E1 and E2. */ | |
4885 | ||
4886 | static int | |
4887 | eq_stmt_vertex_info (const void *e1, const void *e2) | |
4888 | { | |
4889 | const struct rdg_vertex_info *elt1 = (const struct rdg_vertex_info *) e1; | |
4890 | const struct rdg_vertex_info *elt2 = (const struct rdg_vertex_info *) e2; | |
4891 | ||
4892 | return elt1->stmt == elt2->stmt; | |
4893 | } | |
4894 | ||
4895 | /* Free the element E. */ | |
4896 | ||
4897 | static void | |
4898 | hash_stmt_vertex_del (void *e) | |
4899 | { | |
4900 | free (e); | |
4901 | } | |
4902 | ||
f8bf9252 SP |
4903 | /* Build the Reduced Dependence Graph (RDG) with one vertex per |
4904 | statement of the loop nest, and one edge per data dependence or | |
4905 | scalar dependence. */ | |
4906 | ||
4907 | struct graph * | |
4908 | build_empty_rdg (int n_stmts) | |
4909 | { | |
4910 | int nb_data_refs = 10; | |
4911 | struct graph *rdg = new_graph (n_stmts); | |
4912 | ||
4913 | rdg->indices = htab_create (nb_data_refs, hash_stmt_vertex_info, | |
4914 | eq_stmt_vertex_info, hash_stmt_vertex_del); | |
4915 | return rdg; | |
4916 | } | |
4917 | ||
dea61d92 SP |
4918 | /* Build the Reduced Dependence Graph (RDG) with one vertex per |
4919 | statement of the loop nest, and one edge per data dependence or | |
4920 | scalar dependence. */ | |
3a796c6f SP |
4921 | |
4922 | struct graph * | |
4923 | build_rdg (struct loop *loop) | |
4924 | { | |
4925 | int nb_data_refs = 10; | |
4926 | struct graph *rdg = NULL; | |
4927 | VEC (ddr_p, heap) *dependence_relations; | |
4928 | VEC (data_reference_p, heap) *datarefs; | |
726a989a | 4929 | VEC (gimple, heap) *stmts = VEC_alloc (gimple, heap, nb_data_refs); |
3a796c6f SP |
4930 | |
4931 | dependence_relations = VEC_alloc (ddr_p, heap, nb_data_refs * nb_data_refs) ; | |
4932 | datarefs = VEC_alloc (data_reference_p, heap, nb_data_refs); | |
4933 | compute_data_dependences_for_loop (loop, | |
4934 | false, | |
4935 | &datarefs, | |
4936 | &dependence_relations); | |
dea61d92 | 4937 | |
3a796c6f | 4938 | if (!known_dependences_p (dependence_relations)) |
f8bf9252 SP |
4939 | { |
4940 | free_dependence_relations (dependence_relations); | |
4941 | free_data_refs (datarefs); | |
4942 | VEC_free (gimple, heap, stmts); | |
4943 | ||
4944 | return rdg; | |
4945 | } | |
3a796c6f SP |
4946 | |
4947 | stmts_from_loop (loop, &stmts); | |
f8bf9252 | 4948 | rdg = build_empty_rdg (VEC_length (gimple, stmts)); |
dea61d92 SP |
4949 | |
4950 | rdg->indices = htab_create (nb_data_refs, hash_stmt_vertex_info, | |
4951 | eq_stmt_vertex_info, hash_stmt_vertex_del); | |
3a796c6f SP |
4952 | create_rdg_vertices (rdg, stmts); |
4953 | create_rdg_edges (rdg, dependence_relations); | |
4954 | ||
726a989a | 4955 | VEC_free (gimple, heap, stmts); |
3a796c6f SP |
4956 | return rdg; |
4957 | } | |
dea61d92 SP |
4958 | |
4959 | /* Free the reduced dependence graph RDG. */ | |
4960 | ||
4961 | void | |
4962 | free_rdg (struct graph *rdg) | |
4963 | { | |
4964 | int i; | |
4965 | ||
4966 | for (i = 0; i < rdg->n_vertices; i++) | |
4967 | free (rdg->vertices[i].data); | |
4968 | ||
4969 | htab_delete (rdg->indices); | |
4970 | free_graph (rdg); | |
4971 | } | |
4972 | ||
4973 | /* Initialize STMTS with all the statements of LOOP that contain a | |
4974 | store to memory. */ | |
4975 | ||
4976 | void | |
726a989a | 4977 | stores_from_loop (struct loop *loop, VEC (gimple, heap) **stmts) |
dea61d92 SP |
4978 | { |
4979 | unsigned int i; | |
4980 | basic_block *bbs = get_loop_body_in_dom_order (loop); | |
4981 | ||
4982 | for (i = 0; i < loop->num_nodes; i++) | |
4983 | { | |
4984 | basic_block bb = bbs[i]; | |
726a989a | 4985 | gimple_stmt_iterator bsi; |
dea61d92 | 4986 | |
726a989a | 4987 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
5006671f | 4988 | if (gimple_vdef (gsi_stmt (bsi))) |
726a989a | 4989 | VEC_safe_push (gimple, heap, *stmts, gsi_stmt (bsi)); |
dea61d92 SP |
4990 | } |
4991 | ||
4992 | free (bbs); | |
4993 | } | |
4994 | ||
4995 | /* For a data reference REF, return the declaration of its base | |
4996 | address or NULL_TREE if the base is not determined. */ | |
4997 | ||
4998 | static inline tree | |
726a989a | 4999 | ref_base_address (gimple stmt, data_ref_loc *ref) |
dea61d92 SP |
5000 | { |
5001 | tree base = NULL_TREE; | |
5002 | tree base_address; | |
5003 | struct data_reference *dr = XCNEW (struct data_reference); | |
5004 | ||
5005 | DR_STMT (dr) = stmt; | |
5006 | DR_REF (dr) = *ref->pos; | |
5007 | dr_analyze_innermost (dr); | |
5008 | base_address = DR_BASE_ADDRESS (dr); | |
5009 | ||
5010 | if (!base_address) | |
5011 | goto end; | |
5012 | ||
5013 | switch (TREE_CODE (base_address)) | |
5014 | { | |
5015 | case ADDR_EXPR: | |
5016 | base = TREE_OPERAND (base_address, 0); | |
5017 | break; | |
5018 | ||
5019 | default: | |
5020 | base = base_address; | |
5021 | break; | |
5022 | } | |
5023 | ||
5024 | end: | |
5025 | free_data_ref (dr); | |
5026 | return base; | |
5027 | } | |
5028 | ||
5029 | /* Determines whether the statement from vertex V of the RDG has a | |
5030 | definition used outside the loop that contains this statement. */ | |
5031 | ||
5032 | bool | |
5033 | rdg_defs_used_in_other_loops_p (struct graph *rdg, int v) | |
5034 | { | |
726a989a | 5035 | gimple stmt = RDG_STMT (rdg, v); |
dea61d92 SP |
5036 | struct loop *loop = loop_containing_stmt (stmt); |
5037 | use_operand_p imm_use_p; | |
5038 | imm_use_iterator iterator; | |
5039 | ssa_op_iter it; | |
5040 | def_operand_p def_p; | |
5041 | ||
5042 | if (!loop) | |
5043 | return true; | |
5044 | ||
5045 | FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, it, SSA_OP_DEF) | |
5046 | { | |
5047 | FOR_EACH_IMM_USE_FAST (imm_use_p, iterator, DEF_FROM_PTR (def_p)) | |
5048 | { | |
5049 | if (loop_containing_stmt (USE_STMT (imm_use_p)) != loop) | |
5050 | return true; | |
5051 | } | |
5052 | } | |
5053 | ||
5054 | return false; | |
5055 | } | |
5056 | ||
5057 | /* Determines whether statements S1 and S2 access to similar memory | |
5058 | locations. Two memory accesses are considered similar when they | |
5059 | have the same base address declaration, i.e. when their | |
5060 | ref_base_address is the same. */ | |
5061 | ||
5062 | bool | |
726a989a | 5063 | have_similar_memory_accesses (gimple s1, gimple s2) |
dea61d92 SP |
5064 | { |
5065 | bool res = false; | |
5066 | unsigned i, j; | |
5067 | VEC (data_ref_loc, heap) *refs1, *refs2; | |
5068 | data_ref_loc *ref1, *ref2; | |
5069 | ||
5070 | get_references_in_stmt (s1, &refs1); | |
5071 | get_references_in_stmt (s2, &refs2); | |
5072 | ||
5073 | for (i = 0; VEC_iterate (data_ref_loc, refs1, i, ref1); i++) | |
5074 | { | |
5075 | tree base1 = ref_base_address (s1, ref1); | |
5076 | ||
5077 | if (base1) | |
5078 | for (j = 0; VEC_iterate (data_ref_loc, refs2, j, ref2); j++) | |
5079 | if (base1 == ref_base_address (s2, ref2)) | |
5080 | { | |
5081 | res = true; | |
5082 | goto end; | |
5083 | } | |
5084 | } | |
5085 | ||
5086 | end: | |
5087 | VEC_free (data_ref_loc, heap, refs1); | |
5088 | VEC_free (data_ref_loc, heap, refs2); | |
5089 | return res; | |
5090 | } | |
5091 | ||
5092 | /* Helper function for the hashtab. */ | |
5093 | ||
5094 | static int | |
5095 | have_similar_memory_accesses_1 (const void *s1, const void *s2) | |
5096 | { | |
726a989a RB |
5097 | return have_similar_memory_accesses (CONST_CAST_GIMPLE ((const_gimple) s1), |
5098 | CONST_CAST_GIMPLE ((const_gimple) s2)); | |
dea61d92 SP |
5099 | } |
5100 | ||
5101 | /* Helper function for the hashtab. */ | |
5102 | ||
5103 | static hashval_t | |
5104 | ref_base_address_1 (const void *s) | |
5105 | { | |
726a989a | 5106 | gimple stmt = CONST_CAST_GIMPLE ((const_gimple) s); |
dea61d92 SP |
5107 | unsigned i; |
5108 | VEC (data_ref_loc, heap) *refs; | |
5109 | data_ref_loc *ref; | |
5110 | hashval_t res = 0; | |
5111 | ||
5112 | get_references_in_stmt (stmt, &refs); | |
5113 | ||
5114 | for (i = 0; VEC_iterate (data_ref_loc, refs, i, ref); i++) | |
5115 | if (!ref->is_read) | |
5116 | { | |
5117 | res = htab_hash_pointer (ref_base_address (stmt, ref)); | |
5118 | break; | |
5119 | } | |
5120 | ||
5121 | VEC_free (data_ref_loc, heap, refs); | |
5122 | return res; | |
5123 | } | |
5124 | ||
5125 | /* Try to remove duplicated write data references from STMTS. */ | |
5126 | ||
5127 | void | |
726a989a | 5128 | remove_similar_memory_refs (VEC (gimple, heap) **stmts) |
dea61d92 SP |
5129 | { |
5130 | unsigned i; | |
726a989a RB |
5131 | gimple stmt; |
5132 | htab_t seen = htab_create (VEC_length (gimple, *stmts), ref_base_address_1, | |
dea61d92 SP |
5133 | have_similar_memory_accesses_1, NULL); |
5134 | ||
726a989a | 5135 | for (i = 0; VEC_iterate (gimple, *stmts, i, stmt); ) |
dea61d92 SP |
5136 | { |
5137 | void **slot; | |
5138 | ||
5139 | slot = htab_find_slot (seen, stmt, INSERT); | |
5140 | ||
5141 | if (*slot) | |
726a989a | 5142 | VEC_ordered_remove (gimple, *stmts, i); |
dea61d92 SP |
5143 | else |
5144 | { | |
5145 | *slot = (void *) stmt; | |
5146 | i++; | |
5147 | } | |
5148 | } | |
5149 | ||
5150 | htab_delete (seen); | |
5151 | } | |
5152 | ||
9f275479 JS |
5153 | /* Returns the index of PARAMETER in the parameters vector of the |
5154 | ACCESS_MATRIX. If PARAMETER does not exist return -1. */ | |
5155 | ||
5156 | int | |
5157 | access_matrix_get_index_for_parameter (tree parameter, | |
5158 | struct access_matrix *access_matrix) | |
5159 | { | |
5160 | int i; | |
5161 | VEC (tree,heap) *lambda_parameters = AM_PARAMETERS (access_matrix); | |
5162 | tree lambda_parameter; | |
5163 | ||
5164 | for (i = 0; VEC_iterate (tree, lambda_parameters, i, lambda_parameter); i++) | |
5165 | if (lambda_parameter == parameter) | |
5166 | return i + AM_NB_INDUCTION_VARS (access_matrix); | |
5167 | ||
5168 | return -1; | |
5169 | } |