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56cf8686 | 1 | /* Data references and dependences detectors. |
c75c517d | 2 | Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 |
66647d44 | 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 | |
b8698a0f L |
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 | |
56cf8686 SP |
29 | the array is accessed twice at iterations x and y if and only if: |
30 | | chrec1 (x) == chrec2 (y). | |
b8698a0f | 31 | |
56cf8686 | 32 | The goals of this analysis are: |
b8698a0f | 33 | |
56cf8686 SP |
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), | |
b8698a0f | 37 | |
56cf8686 SP |
38 | - when two data references access the same data, to qualify the |
39 | dependence relation with classic dependence representations: | |
b8698a0f | 40 | |
56cf8686 SP |
41 | - distance vectors |
42 | - direction vectors | |
43 | - loop carried level dependence | |
44 | - polyhedron dependence | |
45 | or with the chains of recurrences based representation, | |
b8698a0f L |
46 | |
47 | - to define a knowledge base for storing the data dependence | |
56cf8686 | 48 | information, |
b8698a0f | 49 | |
56cf8686 | 50 | - to define an interface to access this data. |
b8698a0f L |
51 | |
52 | ||
56cf8686 | 53 | Definitions: |
b8698a0f | 54 | |
56cf8686 SP |
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 | |
b8698a0f | 61 | solutions are integer constants, for example the equation |
56cf8686 SP |
62 | | 3*x + 2*y = 1 |
63 | has an integer solution x = 1 and y = -1. | |
b8698a0f | 64 | |
56cf8686 | 65 | References: |
b8698a0f | 66 | |
56cf8686 SP |
67 | - "Advanced Compilation for High Performance Computing" by Randy |
68 | Allen and Ken Kennedy. | |
b8698a0f L |
69 | http://citeseer.ist.psu.edu/goff91practical.html |
70 | ||
71 | - "Loop Transformations for Restructuring Compilers - The Foundations" | |
56cf8686 SP |
72 | by Utpal Banerjee. |
73 | ||
b8698a0f | 74 | |
56cf8686 SP |
75 | */ |
76 | ||
77 | #include "config.h" | |
78 | #include "system.h" | |
79 | #include "coretypes.h" | |
cf835838 | 80 | #include "gimple-pretty-print.h" |
56cf8686 | 81 | #include "tree-flow.h" |
56cf8686 | 82 | #include "cfgloop.h" |
56cf8686 SP |
83 | #include "tree-data-ref.h" |
84 | #include "tree-scalar-evolution.h" | |
85 | #include "tree-pass.h" | |
946e1bc7 | 86 | #include "langhooks.h" |
56cf8686 | 87 | |
0ff4040e SP |
88 | static struct datadep_stats |
89 | { | |
90 | int num_dependence_tests; | |
91 | int num_dependence_dependent; | |
92 | int num_dependence_independent; | |
93 | int num_dependence_undetermined; | |
94 | ||
95 | int num_subscript_tests; | |
96 | int num_subscript_undetermined; | |
97 | int num_same_subscript_function; | |
98 | ||
99 | int num_ziv; | |
100 | int num_ziv_independent; | |
101 | int num_ziv_dependent; | |
102 | int num_ziv_unimplemented; | |
103 | ||
104 | int num_siv; | |
105 | int num_siv_independent; | |
106 | int num_siv_dependent; | |
107 | int num_siv_unimplemented; | |
108 | ||
109 | int num_miv; | |
110 | int num_miv_independent; | |
111 | int num_miv_dependent; | |
112 | int num_miv_unimplemented; | |
113 | } dependence_stats; | |
114 | ||
ba42e045 SP |
115 | static bool subscript_dependence_tester_1 (struct data_dependence_relation *, |
116 | struct data_reference *, | |
da9a21f4 SP |
117 | struct data_reference *, |
118 | struct loop *); | |
56cf8686 SP |
119 | /* Returns true iff A divides B. */ |
120 | ||
b8698a0f | 121 | static inline bool |
ed7a4b4b | 122 | tree_fold_divides_p (const_tree a, const_tree b) |
56cf8686 | 123 | { |
b73a6056 RS |
124 | gcc_assert (TREE_CODE (a) == INTEGER_CST); |
125 | gcc_assert (TREE_CODE (b) == INTEGER_CST); | |
126 | return integer_zerop (int_const_binop (TRUNC_MOD_EXPR, b, a, 0)); | |
56cf8686 SP |
127 | } |
128 | ||
86df10e3 SP |
129 | /* Returns true iff A divides B. */ |
130 | ||
b8698a0f | 131 | static inline bool |
86df10e3 SP |
132 | int_divides_p (int a, int b) |
133 | { | |
134 | return ((b % a) == 0); | |
56cf8686 SP |
135 | } |
136 | ||
137 | \f | |
138 | ||
b8698a0f | 139 | /* Dump into FILE all the data references from DATAREFS. */ |
56cf8686 | 140 | |
b8698a0f | 141 | void |
ebf78a47 | 142 | dump_data_references (FILE *file, VEC (data_reference_p, heap) *datarefs) |
56cf8686 SP |
143 | { |
144 | unsigned int i; | |
ebf78a47 SP |
145 | struct data_reference *dr; |
146 | ||
ac47786e | 147 | FOR_EACH_VEC_ELT (data_reference_p, datarefs, i, dr) |
ebf78a47 | 148 | dump_data_reference (file, dr); |
56cf8686 SP |
149 | } |
150 | ||
b8698a0f | 151 | /* Dump into STDERR all the data references from DATAREFS. */ |
a37d995a | 152 | |
24e47c76 | 153 | DEBUG_FUNCTION void |
a37d995a SP |
154 | debug_data_references (VEC (data_reference_p, heap) *datarefs) |
155 | { | |
156 | dump_data_references (stderr, datarefs); | |
157 | } | |
158 | ||
b8698a0f | 159 | /* Dump to STDERR all the dependence relations from DDRS. */ |
dea61d92 | 160 | |
24e47c76 | 161 | DEBUG_FUNCTION void |
dea61d92 SP |
162 | debug_data_dependence_relations (VEC (ddr_p, heap) *ddrs) |
163 | { | |
164 | dump_data_dependence_relations (stderr, ddrs); | |
165 | } | |
166 | ||
b8698a0f | 167 | /* Dump into FILE all the dependence relations from DDRS. */ |
56cf8686 | 168 | |
b8698a0f L |
169 | void |
170 | dump_data_dependence_relations (FILE *file, | |
ebf78a47 | 171 | VEC (ddr_p, heap) *ddrs) |
56cf8686 SP |
172 | { |
173 | unsigned int i; | |
ebf78a47 SP |
174 | struct data_dependence_relation *ddr; |
175 | ||
ac47786e | 176 | FOR_EACH_VEC_ELT (ddr_p, ddrs, i, ddr) |
ebf78a47 | 177 | dump_data_dependence_relation (file, ddr); |
56cf8686 SP |
178 | } |
179 | ||
a37d995a SP |
180 | /* Print to STDERR the data_reference DR. */ |
181 | ||
24e47c76 | 182 | DEBUG_FUNCTION void |
a37d995a SP |
183 | debug_data_reference (struct data_reference *dr) |
184 | { | |
185 | dump_data_reference (stderr, dr); | |
186 | } | |
187 | ||
56cf8686 SP |
188 | /* Dump function for a DATA_REFERENCE structure. */ |
189 | ||
b8698a0f L |
190 | void |
191 | dump_data_reference (FILE *outf, | |
56cf8686 SP |
192 | struct data_reference *dr) |
193 | { | |
194 | unsigned int i; | |
b8698a0f | 195 | |
28c5db57 SP |
196 | fprintf (outf, "#(Data Ref: \n"); |
197 | fprintf (outf, "# bb: %d \n", gimple_bb (DR_STMT (dr))->index); | |
198 | fprintf (outf, "# stmt: "); | |
726a989a | 199 | print_gimple_stmt (outf, DR_STMT (dr), 0, 0); |
03922af3 | 200 | fprintf (outf, "# ref: "); |
56cf8686 | 201 | print_generic_stmt (outf, DR_REF (dr), 0); |
03922af3 | 202 | fprintf (outf, "# base_object: "); |
86a07404 | 203 | print_generic_stmt (outf, DR_BASE_OBJECT (dr), 0); |
b8698a0f | 204 | |
56cf8686 SP |
205 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
206 | { | |
03922af3 | 207 | fprintf (outf, "# Access function %d: ", i); |
56cf8686 SP |
208 | print_generic_stmt (outf, DR_ACCESS_FN (dr, i), 0); |
209 | } | |
03922af3 | 210 | fprintf (outf, "#)\n"); |
56cf8686 SP |
211 | } |
212 | ||
d93817c4 ZD |
213 | /* Dumps the affine function described by FN to the file OUTF. */ |
214 | ||
215 | static void | |
216 | dump_affine_function (FILE *outf, affine_fn fn) | |
217 | { | |
218 | unsigned i; | |
219 | tree coef; | |
220 | ||
221 | print_generic_expr (outf, VEC_index (tree, fn, 0), TDF_SLIM); | |
222 | for (i = 1; VEC_iterate (tree, fn, i, coef); i++) | |
223 | { | |
224 | fprintf (outf, " + "); | |
225 | print_generic_expr (outf, coef, TDF_SLIM); | |
226 | fprintf (outf, " * x_%u", i); | |
227 | } | |
228 | } | |
229 | ||
230 | /* Dumps the conflict function CF to the file OUTF. */ | |
231 | ||
232 | static void | |
233 | dump_conflict_function (FILE *outf, conflict_function *cf) | |
234 | { | |
235 | unsigned i; | |
236 | ||
237 | if (cf->n == NO_DEPENDENCE) | |
238 | fprintf (outf, "no dependence\n"); | |
239 | else if (cf->n == NOT_KNOWN) | |
240 | fprintf (outf, "not known\n"); | |
241 | else | |
242 | { | |
243 | for (i = 0; i < cf->n; i++) | |
244 | { | |
245 | fprintf (outf, "["); | |
246 | dump_affine_function (outf, cf->fns[i]); | |
247 | fprintf (outf, "]\n"); | |
248 | } | |
249 | } | |
250 | } | |
251 | ||
86df10e3 SP |
252 | /* Dump function for a SUBSCRIPT structure. */ |
253 | ||
b8698a0f | 254 | void |
86df10e3 SP |
255 | dump_subscript (FILE *outf, struct subscript *subscript) |
256 | { | |
d93817c4 | 257 | conflict_function *cf = SUB_CONFLICTS_IN_A (subscript); |
86df10e3 SP |
258 | |
259 | fprintf (outf, "\n (subscript \n"); | |
260 | fprintf (outf, " iterations_that_access_an_element_twice_in_A: "); | |
d93817c4 ZD |
261 | dump_conflict_function (outf, cf); |
262 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
263 | { |
264 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
265 | fprintf (outf, " last_conflict: "); | |
266 | print_generic_stmt (outf, last_iteration, 0); | |
267 | } | |
b8698a0f | 268 | |
d93817c4 | 269 | cf = SUB_CONFLICTS_IN_B (subscript); |
86df10e3 | 270 | fprintf (outf, " iterations_that_access_an_element_twice_in_B: "); |
d93817c4 ZD |
271 | dump_conflict_function (outf, cf); |
272 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
273 | { |
274 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
275 | fprintf (outf, " last_conflict: "); | |
276 | print_generic_stmt (outf, last_iteration, 0); | |
277 | } | |
278 | ||
279 | fprintf (outf, " (Subscript distance: "); | |
280 | print_generic_stmt (outf, SUB_DISTANCE (subscript), 0); | |
281 | fprintf (outf, " )\n"); | |
282 | fprintf (outf, " )\n"); | |
283 | } | |
284 | ||
0ff4040e SP |
285 | /* Print the classic direction vector DIRV to OUTF. */ |
286 | ||
287 | void | |
288 | print_direction_vector (FILE *outf, | |
289 | lambda_vector dirv, | |
290 | int length) | |
291 | { | |
292 | int eq; | |
293 | ||
294 | for (eq = 0; eq < length; eq++) | |
295 | { | |
81f40b79 ILT |
296 | enum data_dependence_direction dir = ((enum data_dependence_direction) |
297 | dirv[eq]); | |
0ff4040e SP |
298 | |
299 | switch (dir) | |
300 | { | |
301 | case dir_positive: | |
302 | fprintf (outf, " +"); | |
303 | break; | |
304 | case dir_negative: | |
305 | fprintf (outf, " -"); | |
306 | break; | |
307 | case dir_equal: | |
308 | fprintf (outf, " ="); | |
309 | break; | |
310 | case dir_positive_or_equal: | |
311 | fprintf (outf, " +="); | |
312 | break; | |
313 | case dir_positive_or_negative: | |
314 | fprintf (outf, " +-"); | |
315 | break; | |
316 | case dir_negative_or_equal: | |
317 | fprintf (outf, " -="); | |
318 | break; | |
319 | case dir_star: | |
320 | fprintf (outf, " *"); | |
321 | break; | |
322 | default: | |
323 | fprintf (outf, "indep"); | |
324 | break; | |
325 | } | |
326 | } | |
327 | fprintf (outf, "\n"); | |
328 | } | |
329 | ||
ba42e045 SP |
330 | /* Print a vector of direction vectors. */ |
331 | ||
332 | void | |
333 | print_dir_vectors (FILE *outf, VEC (lambda_vector, heap) *dir_vects, | |
334 | int length) | |
335 | { | |
336 | unsigned j; | |
337 | lambda_vector v; | |
338 | ||
ac47786e | 339 | FOR_EACH_VEC_ELT (lambda_vector, dir_vects, j, v) |
ba42e045 SP |
340 | print_direction_vector (outf, v, length); |
341 | } | |
342 | ||
b305e3da SP |
343 | /* Print out a vector VEC of length N to OUTFILE. */ |
344 | ||
345 | static inline void | |
346 | print_lambda_vector (FILE * outfile, lambda_vector vector, int n) | |
347 | { | |
348 | int i; | |
349 | ||
350 | for (i = 0; i < n; i++) | |
351 | fprintf (outfile, "%3d ", vector[i]); | |
352 | fprintf (outfile, "\n"); | |
353 | } | |
354 | ||
ba42e045 SP |
355 | /* Print a vector of distance vectors. */ |
356 | ||
357 | void | |
358 | print_dist_vectors (FILE *outf, VEC (lambda_vector, heap) *dist_vects, | |
359 | int length) | |
360 | { | |
361 | unsigned j; | |
362 | lambda_vector v; | |
363 | ||
ac47786e | 364 | FOR_EACH_VEC_ELT (lambda_vector, dist_vects, j, v) |
ba42e045 SP |
365 | print_lambda_vector (outf, v, length); |
366 | } | |
367 | ||
368 | /* Debug version. */ | |
369 | ||
24e47c76 | 370 | DEBUG_FUNCTION void |
ba42e045 SP |
371 | debug_data_dependence_relation (struct data_dependence_relation *ddr) |
372 | { | |
373 | dump_data_dependence_relation (stderr, ddr); | |
374 | } | |
375 | ||
56cf8686 SP |
376 | /* Dump function for a DATA_DEPENDENCE_RELATION structure. */ |
377 | ||
b8698a0f L |
378 | void |
379 | dump_data_dependence_relation (FILE *outf, | |
56cf8686 SP |
380 | struct data_dependence_relation *ddr) |
381 | { | |
56cf8686 | 382 | struct data_reference *dra, *drb; |
86df10e3 | 383 | |
86df10e3 | 384 | fprintf (outf, "(Data Dep: \n"); |
dea61d92 | 385 | |
ed2024ba MJ |
386 | if (!ddr || DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) |
387 | { | |
b61b1f17 MM |
388 | if (ddr) |
389 | { | |
390 | dra = DDR_A (ddr); | |
391 | drb = DDR_B (ddr); | |
392 | if (dra) | |
393 | dump_data_reference (outf, dra); | |
394 | else | |
395 | fprintf (outf, " (nil)\n"); | |
396 | if (drb) | |
397 | dump_data_reference (outf, drb); | |
398 | else | |
399 | fprintf (outf, " (nil)\n"); | |
400 | } | |
ed2024ba MJ |
401 | fprintf (outf, " (don't know)\n)\n"); |
402 | return; | |
403 | } | |
404 | ||
405 | dra = DDR_A (ddr); | |
406 | drb = DDR_B (ddr); | |
dea61d92 SP |
407 | dump_data_reference (outf, dra); |
408 | dump_data_reference (outf, drb); | |
409 | ||
ed2024ba | 410 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
56cf8686 | 411 | fprintf (outf, " (no dependence)\n"); |
b8698a0f | 412 | |
86df10e3 | 413 | else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
56cf8686 | 414 | { |
86df10e3 | 415 | unsigned int i; |
ba42e045 | 416 | struct loop *loopi; |
304afda6 | 417 | |
56cf8686 SP |
418 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
419 | { | |
56cf8686 SP |
420 | fprintf (outf, " access_fn_A: "); |
421 | print_generic_stmt (outf, DR_ACCESS_FN (dra, i), 0); | |
422 | fprintf (outf, " access_fn_B: "); | |
423 | print_generic_stmt (outf, DR_ACCESS_FN (drb, i), 0); | |
86df10e3 | 424 | dump_subscript (outf, DDR_SUBSCRIPT (ddr, i)); |
56cf8686 | 425 | } |
304afda6 | 426 | |
3d8864c0 | 427 | fprintf (outf, " inner loop index: %d\n", DDR_INNER_LOOP (ddr)); |
ba42e045 | 428 | fprintf (outf, " loop nest: ("); |
ac47786e | 429 | FOR_EACH_VEC_ELT (loop_p, DDR_LOOP_NEST (ddr), i, loopi) |
ba42e045 SP |
430 | fprintf (outf, "%d ", loopi->num); |
431 | fprintf (outf, ")\n"); | |
432 | ||
304afda6 | 433 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) |
56cf8686 | 434 | { |
304afda6 SP |
435 | fprintf (outf, " distance_vector: "); |
436 | print_lambda_vector (outf, DDR_DIST_VECT (ddr, i), | |
ba42e045 | 437 | DDR_NB_LOOPS (ddr)); |
86df10e3 | 438 | } |
304afda6 SP |
439 | |
440 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
86df10e3 | 441 | { |
304afda6 | 442 | fprintf (outf, " direction_vector: "); |
0ff4040e | 443 | print_direction_vector (outf, DDR_DIR_VECT (ddr, i), |
ba42e045 | 444 | DDR_NB_LOOPS (ddr)); |
56cf8686 | 445 | } |
56cf8686 SP |
446 | } |
447 | ||
448 | fprintf (outf, ")\n"); | |
449 | } | |
450 | ||
56cf8686 SP |
451 | /* Dump function for a DATA_DEPENDENCE_DIRECTION structure. */ |
452 | ||
453 | void | |
b8698a0f | 454 | dump_data_dependence_direction (FILE *file, |
56cf8686 SP |
455 | enum data_dependence_direction dir) |
456 | { | |
457 | switch (dir) | |
458 | { | |
b8698a0f | 459 | case dir_positive: |
56cf8686 SP |
460 | fprintf (file, "+"); |
461 | break; | |
b8698a0f | 462 | |
56cf8686 SP |
463 | case dir_negative: |
464 | fprintf (file, "-"); | |
465 | break; | |
b8698a0f | 466 | |
56cf8686 SP |
467 | case dir_equal: |
468 | fprintf (file, "="); | |
469 | break; | |
b8698a0f | 470 | |
56cf8686 SP |
471 | case dir_positive_or_negative: |
472 | fprintf (file, "+-"); | |
473 | break; | |
b8698a0f L |
474 | |
475 | case dir_positive_or_equal: | |
56cf8686 SP |
476 | fprintf (file, "+="); |
477 | break; | |
b8698a0f L |
478 | |
479 | case dir_negative_or_equal: | |
56cf8686 SP |
480 | fprintf (file, "-="); |
481 | break; | |
b8698a0f L |
482 | |
483 | case dir_star: | |
484 | fprintf (file, "*"); | |
56cf8686 | 485 | break; |
b8698a0f L |
486 | |
487 | default: | |
56cf8686 SP |
488 | break; |
489 | } | |
490 | } | |
491 | ||
86df10e3 SP |
492 | /* Dumps the distance and direction vectors in FILE. DDRS contains |
493 | the dependence relations, and VECT_SIZE is the size of the | |
494 | dependence vectors, or in other words the number of loops in the | |
495 | considered nest. */ | |
496 | ||
b8698a0f | 497 | void |
ebf78a47 | 498 | dump_dist_dir_vectors (FILE *file, VEC (ddr_p, heap) *ddrs) |
86df10e3 | 499 | { |
304afda6 | 500 | unsigned int i, j; |
ebf78a47 SP |
501 | struct data_dependence_relation *ddr; |
502 | lambda_vector v; | |
86df10e3 | 503 | |
ac47786e | 504 | FOR_EACH_VEC_ELT (ddr_p, ddrs, i, ddr) |
ebf78a47 SP |
505 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_AFFINE_P (ddr)) |
506 | { | |
ac47786e | 507 | FOR_EACH_VEC_ELT (lambda_vector, DDR_DIST_VECTS (ddr), j, v) |
ebf78a47 SP |
508 | { |
509 | fprintf (file, "DISTANCE_V ("); | |
510 | print_lambda_vector (file, v, DDR_NB_LOOPS (ddr)); | |
511 | fprintf (file, ")\n"); | |
512 | } | |
513 | ||
ac47786e | 514 | FOR_EACH_VEC_ELT (lambda_vector, DDR_DIR_VECTS (ddr), j, v) |
ebf78a47 SP |
515 | { |
516 | fprintf (file, "DIRECTION_V ("); | |
517 | print_direction_vector (file, v, DDR_NB_LOOPS (ddr)); | |
518 | fprintf (file, ")\n"); | |
519 | } | |
520 | } | |
304afda6 | 521 | |
86df10e3 SP |
522 | fprintf (file, "\n\n"); |
523 | } | |
524 | ||
525 | /* Dumps the data dependence relations DDRS in FILE. */ | |
526 | ||
b8698a0f | 527 | void |
ebf78a47 | 528 | dump_ddrs (FILE *file, VEC (ddr_p, heap) *ddrs) |
86df10e3 SP |
529 | { |
530 | unsigned int i; | |
ebf78a47 SP |
531 | struct data_dependence_relation *ddr; |
532 | ||
ac47786e | 533 | FOR_EACH_VEC_ELT (ddr_p, ddrs, i, ddr) |
ebf78a47 | 534 | dump_data_dependence_relation (file, ddr); |
86df10e3 | 535 | |
86df10e3 SP |
536 | fprintf (file, "\n\n"); |
537 | } | |
538 | ||
726a989a RB |
539 | /* Helper function for split_constant_offset. Expresses OP0 CODE OP1 |
540 | (the type of the result is TYPE) as VAR + OFF, where OFF is a nonzero | |
541 | constant of type ssizetype, and returns true. If we cannot do this | |
542 | with OFF nonzero, OFF and VAR are set to NULL_TREE instead and false | |
543 | is returned. */ | |
86a07404 | 544 | |
726a989a RB |
545 | static bool |
546 | split_constant_offset_1 (tree type, tree op0, enum tree_code code, tree op1, | |
547 | tree *var, tree *off) | |
86a07404 | 548 | { |
3cb960c7 ZD |
549 | tree var0, var1; |
550 | tree off0, off1; | |
726a989a | 551 | enum tree_code ocode = code; |
86a07404 | 552 | |
726a989a RB |
553 | *var = NULL_TREE; |
554 | *off = NULL_TREE; | |
86a07404 | 555 | |
5be014d5 | 556 | switch (code) |
86a07404 | 557 | { |
3cb960c7 ZD |
558 | case INTEGER_CST: |
559 | *var = build_int_cst (type, 0); | |
726a989a RB |
560 | *off = fold_convert (ssizetype, op0); |
561 | return true; | |
86a07404 | 562 | |
5be014d5 | 563 | case POINTER_PLUS_EXPR: |
726a989a | 564 | ocode = PLUS_EXPR; |
5be014d5 | 565 | /* FALLTHROUGH */ |
3cb960c7 ZD |
566 | case PLUS_EXPR: |
567 | case MINUS_EXPR: | |
726a989a RB |
568 | split_constant_offset (op0, &var0, &off0); |
569 | split_constant_offset (op1, &var1, &off1); | |
570 | *var = fold_build2 (code, type, var0, var1); | |
571 | *off = size_binop (ocode, off0, off1); | |
572 | return true; | |
86a07404 | 573 | |
86a07404 | 574 | case MULT_EXPR: |
726a989a RB |
575 | if (TREE_CODE (op1) != INTEGER_CST) |
576 | return false; | |
3cb960c7 | 577 | |
726a989a RB |
578 | split_constant_offset (op0, &var0, &off0); |
579 | *var = fold_build2 (MULT_EXPR, type, var0, op1); | |
580 | *off = size_binop (MULT_EXPR, off0, fold_convert (ssizetype, op1)); | |
581 | return true; | |
86a07404 | 582 | |
3cb960c7 ZD |
583 | case ADDR_EXPR: |
584 | { | |
726a989a | 585 | tree base, poffset; |
3cb960c7 ZD |
586 | HOST_WIDE_INT pbitsize, pbitpos; |
587 | enum machine_mode pmode; | |
588 | int punsignedp, pvolatilep; | |
86a07404 | 589 | |
da4b6efc | 590 | op0 = TREE_OPERAND (op0, 0); |
726a989a RB |
591 | if (!handled_component_p (op0)) |
592 | return false; | |
86a07404 | 593 | |
726a989a | 594 | base = get_inner_reference (op0, &pbitsize, &pbitpos, &poffset, |
3cb960c7 | 595 | &pmode, &punsignedp, &pvolatilep, false); |
86a07404 | 596 | |
3cb960c7 | 597 | if (pbitpos % BITS_PER_UNIT != 0) |
726a989a | 598 | return false; |
3cb960c7 ZD |
599 | base = build_fold_addr_expr (base); |
600 | off0 = ssize_int (pbitpos / BITS_PER_UNIT); | |
86a07404 | 601 | |
3cb960c7 ZD |
602 | if (poffset) |
603 | { | |
604 | split_constant_offset (poffset, &poffset, &off1); | |
605 | off0 = size_binop (PLUS_EXPR, off0, off1); | |
36ad7922 JJ |
606 | if (POINTER_TYPE_P (TREE_TYPE (base))) |
607 | base = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (base), | |
608 | base, fold_convert (sizetype, poffset)); | |
609 | else | |
610 | base = fold_build2 (PLUS_EXPR, TREE_TYPE (base), base, | |
611 | fold_convert (TREE_TYPE (base), poffset)); | |
3cb960c7 ZD |
612 | } |
613 | ||
6481b879 JJ |
614 | var0 = fold_convert (type, base); |
615 | ||
616 | /* If variable length types are involved, punt, otherwise casts | |
617 | might be converted into ARRAY_REFs in gimplify_conversion. | |
618 | To compute that ARRAY_REF's element size TYPE_SIZE_UNIT, which | |
619 | possibly no longer appears in current GIMPLE, might resurface. | |
620 | This perhaps could run | |
1a87cf0c | 621 | if (CONVERT_EXPR_P (var0)) |
6481b879 JJ |
622 | { |
623 | gimplify_conversion (&var0); | |
624 | // Attempt to fill in any within var0 found ARRAY_REF's | |
625 | // element size from corresponding op embedded ARRAY_REF, | |
626 | // if unsuccessful, just punt. | |
627 | } */ | |
628 | while (POINTER_TYPE_P (type)) | |
629 | type = TREE_TYPE (type); | |
630 | if (int_size_in_bytes (type) < 0) | |
726a989a | 631 | return false; |
6481b879 JJ |
632 | |
633 | *var = var0; | |
3cb960c7 | 634 | *off = off0; |
726a989a | 635 | return true; |
3cb960c7 | 636 | } |
86a07404 | 637 | |
06cb4f79 JS |
638 | case SSA_NAME: |
639 | { | |
726a989a RB |
640 | gimple def_stmt = SSA_NAME_DEF_STMT (op0); |
641 | enum tree_code subcode; | |
06cb4f79 | 642 | |
726a989a RB |
643 | if (gimple_code (def_stmt) != GIMPLE_ASSIGN) |
644 | return false; | |
645 | ||
646 | var0 = gimple_assign_rhs1 (def_stmt); | |
647 | subcode = gimple_assign_rhs_code (def_stmt); | |
648 | var1 = gimple_assign_rhs2 (def_stmt); | |
649 | ||
650 | return split_constant_offset_1 (type, var0, subcode, var1, var, off); | |
06cb4f79 | 651 | } |
b61b1f17 MM |
652 | CASE_CONVERT: |
653 | { | |
654 | /* We must not introduce undefined overflow, and we must not change the value. | |
655 | Hence we're okay if the inner type doesn't overflow to start with | |
656 | (pointer or signed), the outer type also is an integer or pointer | |
657 | and the outer precision is at least as large as the inner. */ | |
658 | tree itype = TREE_TYPE (op0); | |
659 | if ((POINTER_TYPE_P (itype) | |
660 | || (INTEGRAL_TYPE_P (itype) && TYPE_OVERFLOW_UNDEFINED (itype))) | |
661 | && TYPE_PRECISION (type) >= TYPE_PRECISION (itype) | |
662 | && (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type))) | |
663 | { | |
664 | split_constant_offset (op0, &var0, off); | |
665 | *var = fold_convert (type, var0); | |
666 | return true; | |
667 | } | |
668 | return false; | |
669 | } | |
06cb4f79 | 670 | |
86a07404 | 671 | default: |
726a989a | 672 | return false; |
86a07404 | 673 | } |
726a989a RB |
674 | } |
675 | ||
676 | /* Expresses EXP as VAR + OFF, where off is a constant. The type of OFF | |
677 | will be ssizetype. */ | |
678 | ||
679 | void | |
680 | split_constant_offset (tree exp, tree *var, tree *off) | |
681 | { | |
682 | tree type = TREE_TYPE (exp), otype, op0, op1, e, o; | |
683 | enum tree_code code; | |
86a07404 | 684 | |
726a989a | 685 | *var = exp; |
3cb960c7 | 686 | *off = ssize_int (0); |
726a989a RB |
687 | STRIP_NOPS (exp); |
688 | ||
f471fe72 | 689 | if (tree_is_chrec (exp)) |
726a989a RB |
690 | return; |
691 | ||
692 | otype = TREE_TYPE (exp); | |
693 | code = TREE_CODE (exp); | |
694 | extract_ops_from_tree (exp, &code, &op0, &op1); | |
695 | if (split_constant_offset_1 (otype, op0, code, op1, &e, &o)) | |
696 | { | |
697 | *var = fold_convert (type, e); | |
698 | *off = o; | |
699 | } | |
86a07404 IR |
700 | } |
701 | ||
3cb960c7 ZD |
702 | /* Returns the address ADDR of an object in a canonical shape (without nop |
703 | casts, and with type of pointer to the object). */ | |
86a07404 IR |
704 | |
705 | static tree | |
3cb960c7 | 706 | canonicalize_base_object_address (tree addr) |
86a07404 | 707 | { |
bbc8a8dc ZD |
708 | tree orig = addr; |
709 | ||
3cb960c7 | 710 | STRIP_NOPS (addr); |
86a07404 | 711 | |
bbc8a8dc ZD |
712 | /* The base address may be obtained by casting from integer, in that case |
713 | keep the cast. */ | |
714 | if (!POINTER_TYPE_P (TREE_TYPE (addr))) | |
715 | return orig; | |
716 | ||
3cb960c7 ZD |
717 | if (TREE_CODE (addr) != ADDR_EXPR) |
718 | return addr; | |
86a07404 | 719 | |
3cb960c7 | 720 | return build_fold_addr_expr (TREE_OPERAND (addr, 0)); |
86a07404 IR |
721 | } |
722 | ||
b8698a0f | 723 | /* Analyzes the behavior of the memory reference DR in the innermost loop or |
a70d6342 IR |
724 | basic block that contains it. Returns true if analysis succeed or false |
725 | otherwise. */ | |
86a07404 | 726 | |
3661e899 | 727 | bool |
3cb960c7 | 728 | dr_analyze_innermost (struct data_reference *dr) |
86a07404 | 729 | { |
726a989a | 730 | gimple stmt = DR_STMT (dr); |
3cb960c7 ZD |
731 | struct loop *loop = loop_containing_stmt (stmt); |
732 | tree ref = DR_REF (dr); | |
86a07404 | 733 | HOST_WIDE_INT pbitsize, pbitpos; |
3cb960c7 | 734 | tree base, poffset; |
86a07404 IR |
735 | enum machine_mode pmode; |
736 | int punsignedp, pvolatilep; | |
3cb960c7 ZD |
737 | affine_iv base_iv, offset_iv; |
738 | tree init, dinit, step; | |
a70d6342 | 739 | bool in_loop = (loop && loop->num); |
3cb960c7 ZD |
740 | |
741 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
742 | fprintf (dump_file, "analyze_innermost: "); | |
86a07404 | 743 | |
3cb960c7 ZD |
744 | base = get_inner_reference (ref, &pbitsize, &pbitpos, &poffset, |
745 | &pmode, &punsignedp, &pvolatilep, false); | |
746 | gcc_assert (base != NULL_TREE); | |
86a07404 | 747 | |
3cb960c7 | 748 | if (pbitpos % BITS_PER_UNIT != 0) |
86a07404 | 749 | { |
3cb960c7 ZD |
750 | if (dump_file && (dump_flags & TDF_DETAILS)) |
751 | fprintf (dump_file, "failed: bit offset alignment.\n"); | |
3661e899 | 752 | return false; |
3cb960c7 | 753 | } |
86a07404 | 754 | |
70f34814 RG |
755 | if (TREE_CODE (base) == MEM_REF) |
756 | { | |
757 | if (!integer_zerop (TREE_OPERAND (base, 1))) | |
758 | { | |
759 | if (!poffset) | |
760 | { | |
761 | double_int moff = mem_ref_offset (base); | |
762 | poffset = double_int_to_tree (sizetype, moff); | |
763 | } | |
764 | else | |
765 | poffset = size_binop (PLUS_EXPR, poffset, TREE_OPERAND (base, 1)); | |
766 | } | |
767 | base = TREE_OPERAND (base, 0); | |
768 | } | |
769 | else | |
770 | base = build_fold_addr_expr (base); | |
a70d6342 | 771 | if (in_loop) |
3cb960c7 | 772 | { |
b8698a0f | 773 | if (!simple_iv (loop, loop_containing_stmt (stmt), base, &base_iv, |
a70d6342 IR |
774 | false)) |
775 | { | |
776 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
777 | fprintf (dump_file, "failed: evolution of base is not affine.\n"); | |
778 | return false; | |
779 | } | |
780 | } | |
781 | else | |
782 | { | |
783 | base_iv.base = base; | |
784 | base_iv.step = ssize_int (0); | |
785 | base_iv.no_overflow = true; | |
3cb960c7 | 786 | } |
a70d6342 | 787 | |
24adb18f | 788 | if (!poffset) |
3cb960c7 ZD |
789 | { |
790 | offset_iv.base = ssize_int (0); | |
791 | offset_iv.step = ssize_int (0); | |
792 | } | |
24adb18f | 793 | else |
3cb960c7 | 794 | { |
24adb18f IR |
795 | if (!in_loop) |
796 | { | |
797 | offset_iv.base = poffset; | |
798 | offset_iv.step = ssize_int (0); | |
799 | } | |
800 | else if (!simple_iv (loop, loop_containing_stmt (stmt), | |
801 | poffset, &offset_iv, false)) | |
802 | { | |
803 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
804 | fprintf (dump_file, "failed: evolution of offset is not" | |
805 | " affine.\n"); | |
806 | return false; | |
807 | } | |
3cb960c7 | 808 | } |
86a07404 | 809 | |
3cb960c7 ZD |
810 | init = ssize_int (pbitpos / BITS_PER_UNIT); |
811 | split_constant_offset (base_iv.base, &base_iv.base, &dinit); | |
812 | init = size_binop (PLUS_EXPR, init, dinit); | |
813 | split_constant_offset (offset_iv.base, &offset_iv.base, &dinit); | |
814 | init = size_binop (PLUS_EXPR, init, dinit); | |
86a07404 | 815 | |
3cb960c7 ZD |
816 | step = size_binop (PLUS_EXPR, |
817 | fold_convert (ssizetype, base_iv.step), | |
818 | fold_convert (ssizetype, offset_iv.step)); | |
86a07404 | 819 | |
3cb960c7 | 820 | DR_BASE_ADDRESS (dr) = canonicalize_base_object_address (base_iv.base); |
86a07404 | 821 | |
3cb960c7 ZD |
822 | DR_OFFSET (dr) = fold_convert (ssizetype, offset_iv.base); |
823 | DR_INIT (dr) = init; | |
824 | DR_STEP (dr) = step; | |
86a07404 | 825 | |
3cb960c7 | 826 | DR_ALIGNED_TO (dr) = size_int (highest_pow2_factor (offset_iv.base)); |
86a07404 | 827 | |
3cb960c7 ZD |
828 | if (dump_file && (dump_flags & TDF_DETAILS)) |
829 | fprintf (dump_file, "success.\n"); | |
3661e899 TB |
830 | |
831 | return true; | |
3cb960c7 | 832 | } |
86a07404 | 833 | |
3cb960c7 | 834 | /* Determines the base object and the list of indices of memory reference |
5c640e29 | 835 | DR, analyzed in LOOP and instantiated in loop nest NEST. */ |
86a07404 | 836 | |
3cb960c7 | 837 | static void |
5c640e29 | 838 | dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop) |
3cb960c7 | 839 | { |
3cb960c7 ZD |
840 | VEC (tree, heap) *access_fns = NULL; |
841 | tree ref = unshare_expr (DR_REF (dr)), aref = ref, op; | |
a70d6342 IR |
842 | tree base, off, access_fn = NULL_TREE; |
843 | basic_block before_loop = NULL; | |
b8698a0f | 844 | |
a70d6342 IR |
845 | if (nest) |
846 | before_loop = block_before_loop (nest); | |
b8698a0f | 847 | |
3cb960c7 | 848 | while (handled_component_p (aref)) |
86a07404 | 849 | { |
3cb960c7 | 850 | if (TREE_CODE (aref) == ARRAY_REF) |
86a07404 | 851 | { |
3cb960c7 | 852 | op = TREE_OPERAND (aref, 1); |
a70d6342 IR |
853 | if (nest) |
854 | { | |
855 | access_fn = analyze_scalar_evolution (loop, op); | |
856 | access_fn = instantiate_scev (before_loop, loop, access_fn); | |
857 | VEC_safe_push (tree, heap, access_fns, access_fn); | |
858 | } | |
3cb960c7 ZD |
859 | |
860 | TREE_OPERAND (aref, 1) = build_int_cst (TREE_TYPE (op), 0); | |
86a07404 | 861 | } |
b8698a0f | 862 | |
3cb960c7 | 863 | aref = TREE_OPERAND (aref, 0); |
86a07404 IR |
864 | } |
865 | ||
70f34814 RG |
866 | if (nest |
867 | && (INDIRECT_REF_P (aref) | |
868 | || TREE_CODE (aref) == MEM_REF)) | |
86a07404 | 869 | { |
3cb960c7 ZD |
870 | op = TREE_OPERAND (aref, 0); |
871 | access_fn = analyze_scalar_evolution (loop, op); | |
a213b219 | 872 | access_fn = instantiate_scev (before_loop, loop, access_fn); |
3cb960c7 ZD |
873 | base = initial_condition (access_fn); |
874 | split_constant_offset (base, &base, &off); | |
70f34814 RG |
875 | if (TREE_CODE (aref) == MEM_REF) |
876 | off = size_binop (PLUS_EXPR, off, | |
877 | fold_convert (ssizetype, TREE_OPERAND (aref, 1))); | |
3cb960c7 ZD |
878 | access_fn = chrec_replace_initial_condition (access_fn, |
879 | fold_convert (TREE_TYPE (base), off)); | |
880 | ||
881 | TREE_OPERAND (aref, 0) = base; | |
882 | VEC_safe_push (tree, heap, access_fns, access_fn); | |
86a07404 | 883 | } |
86a07404 | 884 | |
70f34814 RG |
885 | if (TREE_CODE (aref) == MEM_REF) |
886 | TREE_OPERAND (aref, 1) | |
887 | = build_int_cst (TREE_TYPE (TREE_OPERAND (aref, 1)), 0); | |
888 | ||
889 | if (TREE_CODE (ref) == MEM_REF | |
890 | && TREE_CODE (TREE_OPERAND (ref, 0)) == ADDR_EXPR | |
891 | && integer_zerop (TREE_OPERAND (ref, 1))) | |
892 | ref = TREE_OPERAND (TREE_OPERAND (ref, 0), 0); | |
893 | ||
894 | /* For canonicalization purposes we'd like to strip all outermost | |
895 | zero-offset component-refs. | |
896 | ??? For now simply handle zero-index array-refs. */ | |
897 | while (TREE_CODE (ref) == ARRAY_REF | |
898 | && integer_zerop (TREE_OPERAND (ref, 1))) | |
899 | ref = TREE_OPERAND (ref, 0); | |
900 | ||
3cb960c7 ZD |
901 | DR_BASE_OBJECT (dr) = ref; |
902 | DR_ACCESS_FNS (dr) = access_fns; | |
86a07404 IR |
903 | } |
904 | ||
3cb960c7 | 905 | /* Extracts the alias analysis information from the memory reference DR. */ |
86a07404 | 906 | |
3cb960c7 ZD |
907 | static void |
908 | dr_analyze_alias (struct data_reference *dr) | |
86a07404 | 909 | { |
3cb960c7 | 910 | tree ref = DR_REF (dr); |
5006671f RG |
911 | tree base = get_base_address (ref), addr; |
912 | ||
70f34814 RG |
913 | if (INDIRECT_REF_P (base) |
914 | || TREE_CODE (base) == MEM_REF) | |
3cb960c7 ZD |
915 | { |
916 | addr = TREE_OPERAND (base, 0); | |
917 | if (TREE_CODE (addr) == SSA_NAME) | |
5006671f | 918 | DR_PTR_INFO (dr) = SSA_NAME_PTR_INFO (addr); |
3cb960c7 | 919 | } |
3cb960c7 | 920 | } |
86a07404 | 921 | |
3cb960c7 | 922 | /* Returns true if the address of DR is invariant. */ |
86a07404 | 923 | |
3cb960c7 ZD |
924 | static bool |
925 | dr_address_invariant_p (struct data_reference *dr) | |
926 | { | |
927 | unsigned i; | |
928 | tree idx; | |
929 | ||
ac47786e | 930 | FOR_EACH_VEC_ELT (tree, DR_ACCESS_FNS (dr), i, idx) |
3cb960c7 ZD |
931 | if (tree_contains_chrecs (idx, NULL)) |
932 | return false; | |
e838422b | 933 | |
e838422b | 934 | return true; |
86a07404 IR |
935 | } |
936 | ||
3cb960c7 | 937 | /* Frees data reference DR. */ |
8fdbc9c6 | 938 | |
dea61d92 | 939 | void |
8fdbc9c6 ZD |
940 | free_data_ref (data_reference_p dr) |
941 | { | |
3cb960c7 | 942 | VEC_free (tree, heap, DR_ACCESS_FNS (dr)); |
8fdbc9c6 ZD |
943 | free (dr); |
944 | } | |
86a07404 | 945 | |
3cb960c7 ZD |
946 | /* Analyzes memory reference MEMREF accessed in STMT. The reference |
947 | is read if IS_READ is true, write otherwise. Returns the | |
5c640e29 SP |
948 | data_reference description of MEMREF. NEST is the outermost loop |
949 | in which the reference should be instantiated, LOOP is the loop in | |
950 | which the data reference should be analyzed. */ | |
86a07404 | 951 | |
5417e022 | 952 | struct data_reference * |
5c640e29 SP |
953 | create_data_ref (loop_p nest, loop_p loop, tree memref, gimple stmt, |
954 | bool is_read) | |
86a07404 | 955 | { |
3cb960c7 | 956 | struct data_reference *dr; |
0ff4040e | 957 | |
3cb960c7 | 958 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e | 959 | { |
3cb960c7 ZD |
960 | fprintf (dump_file, "Creating dr for "); |
961 | print_generic_expr (dump_file, memref, TDF_SLIM); | |
962 | fprintf (dump_file, "\n"); | |
0ff4040e | 963 | } |
e2157b49 | 964 | |
3cb960c7 ZD |
965 | dr = XCNEW (struct data_reference); |
966 | DR_STMT (dr) = stmt; | |
967 | DR_REF (dr) = memref; | |
968 | DR_IS_READ (dr) = is_read; | |
86a07404 | 969 | |
3cb960c7 | 970 | dr_analyze_innermost (dr); |
5c640e29 | 971 | dr_analyze_indices (dr, nest, loop); |
3cb960c7 | 972 | dr_analyze_alias (dr); |
86a07404 IR |
973 | |
974 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
975 | { | |
3cb960c7 | 976 | fprintf (dump_file, "\tbase_address: "); |
86a07404 IR |
977 | print_generic_expr (dump_file, DR_BASE_ADDRESS (dr), TDF_SLIM); |
978 | fprintf (dump_file, "\n\toffset from base address: "); | |
979 | print_generic_expr (dump_file, DR_OFFSET (dr), TDF_SLIM); | |
980 | fprintf (dump_file, "\n\tconstant offset from base address: "); | |
981 | print_generic_expr (dump_file, DR_INIT (dr), TDF_SLIM); | |
86a07404 IR |
982 | fprintf (dump_file, "\n\tstep: "); |
983 | print_generic_expr (dump_file, DR_STEP (dr), TDF_SLIM); | |
3cb960c7 ZD |
984 | fprintf (dump_file, "\n\taligned to: "); |
985 | print_generic_expr (dump_file, DR_ALIGNED_TO (dr), TDF_SLIM); | |
986 | fprintf (dump_file, "\n\tbase_object: "); | |
987 | print_generic_expr (dump_file, DR_BASE_OBJECT (dr), TDF_SLIM); | |
86a07404 | 988 | fprintf (dump_file, "\n"); |
3cb960c7 ZD |
989 | } |
990 | ||
b8698a0f | 991 | return dr; |
86a07404 IR |
992 | } |
993 | ||
bfe068c3 IR |
994 | /* Check if OFFSET1 and OFFSET2 (DR_OFFSETs of some data-refs) are identical |
995 | expressions. */ | |
996 | static bool | |
997 | dr_equal_offsets_p1 (tree offset1, tree offset2) | |
998 | { | |
999 | bool res; | |
1000 | ||
1001 | STRIP_NOPS (offset1); | |
1002 | STRIP_NOPS (offset2); | |
1003 | ||
1004 | if (offset1 == offset2) | |
1005 | return true; | |
1006 | ||
1007 | if (TREE_CODE (offset1) != TREE_CODE (offset2) | |
1008 | || (!BINARY_CLASS_P (offset1) && !UNARY_CLASS_P (offset1))) | |
1009 | return false; | |
1010 | ||
1011 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 0), | |
1012 | TREE_OPERAND (offset2, 0)); | |
1013 | ||
1014 | if (!res || !BINARY_CLASS_P (offset1)) | |
1015 | return res; | |
1016 | ||
1017 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 1), | |
1018 | TREE_OPERAND (offset2, 1)); | |
1019 | ||
1020 | return res; | |
1021 | } | |
1022 | ||
1023 | /* Check if DRA and DRB have equal offsets. */ | |
1024 | bool | |
1025 | dr_equal_offsets_p (struct data_reference *dra, | |
1026 | struct data_reference *drb) | |
1027 | { | |
1028 | tree offset1, offset2; | |
1029 | ||
1030 | offset1 = DR_OFFSET (dra); | |
1031 | offset2 = DR_OFFSET (drb); | |
1032 | ||
1033 | return dr_equal_offsets_p1 (offset1, offset2); | |
1034 | } | |
1035 | ||
d93817c4 ZD |
1036 | /* Returns true if FNA == FNB. */ |
1037 | ||
1038 | static bool | |
1039 | affine_function_equal_p (affine_fn fna, affine_fn fnb) | |
1040 | { | |
1041 | unsigned i, n = VEC_length (tree, fna); | |
86a07404 | 1042 | |
f86289d5 ZD |
1043 | if (n != VEC_length (tree, fnb)) |
1044 | return false; | |
86df10e3 | 1045 | |
d93817c4 ZD |
1046 | for (i = 0; i < n; i++) |
1047 | if (!operand_equal_p (VEC_index (tree, fna, i), | |
1048 | VEC_index (tree, fnb, i), 0)) | |
1049 | return false; | |
1050 | ||
1051 | return true; | |
1052 | } | |
1053 | ||
1054 | /* If all the functions in CF are the same, returns one of them, | |
1055 | otherwise returns NULL. */ | |
1056 | ||
1057 | static affine_fn | |
1058 | common_affine_function (conflict_function *cf) | |
86df10e3 | 1059 | { |
d93817c4 ZD |
1060 | unsigned i; |
1061 | affine_fn comm; | |
1062 | ||
1063 | if (!CF_NONTRIVIAL_P (cf)) | |
1064 | return NULL; | |
1065 | ||
1066 | comm = cf->fns[0]; | |
1067 | ||
1068 | for (i = 1; i < cf->n; i++) | |
1069 | if (!affine_function_equal_p (comm, cf->fns[i])) | |
1070 | return NULL; | |
1071 | ||
1072 | return comm; | |
1073 | } | |
86df10e3 | 1074 | |
d93817c4 ZD |
1075 | /* Returns the base of the affine function FN. */ |
1076 | ||
1077 | static tree | |
1078 | affine_function_base (affine_fn fn) | |
1079 | { | |
1080 | return VEC_index (tree, fn, 0); | |
1081 | } | |
1082 | ||
1083 | /* Returns true if FN is a constant. */ | |
1084 | ||
1085 | static bool | |
1086 | affine_function_constant_p (affine_fn fn) | |
1087 | { | |
1088 | unsigned i; | |
1089 | tree coef; | |
1090 | ||
1091 | for (i = 1; VEC_iterate (tree, fn, i, coef); i++) | |
1092 | if (!integer_zerop (coef)) | |
e2157b49 SP |
1093 | return false; |
1094 | ||
86df10e3 SP |
1095 | return true; |
1096 | } | |
1097 | ||
1baf2906 SP |
1098 | /* Returns true if FN is the zero constant function. */ |
1099 | ||
1100 | static bool | |
1101 | affine_function_zero_p (affine_fn fn) | |
1102 | { | |
1103 | return (integer_zerop (affine_function_base (fn)) | |
1104 | && affine_function_constant_p (fn)); | |
1105 | } | |
1106 | ||
33b30201 SP |
1107 | /* Returns a signed integer type with the largest precision from TA |
1108 | and TB. */ | |
1109 | ||
1110 | static tree | |
1111 | signed_type_for_types (tree ta, tree tb) | |
1112 | { | |
1113 | if (TYPE_PRECISION (ta) > TYPE_PRECISION (tb)) | |
1114 | return signed_type_for (ta); | |
1115 | else | |
1116 | return signed_type_for (tb); | |
1117 | } | |
1118 | ||
d93817c4 ZD |
1119 | /* Applies operation OP on affine functions FNA and FNB, and returns the |
1120 | result. */ | |
1121 | ||
1122 | static affine_fn | |
1123 | affine_fn_op (enum tree_code op, affine_fn fna, affine_fn fnb) | |
1124 | { | |
1125 | unsigned i, n, m; | |
1126 | affine_fn ret; | |
1127 | tree coef; | |
1128 | ||
1129 | if (VEC_length (tree, fnb) > VEC_length (tree, fna)) | |
1130 | { | |
1131 | n = VEC_length (tree, fna); | |
1132 | m = VEC_length (tree, fnb); | |
1133 | } | |
1134 | else | |
1135 | { | |
1136 | n = VEC_length (tree, fnb); | |
1137 | m = VEC_length (tree, fna); | |
1138 | } | |
1139 | ||
1140 | ret = VEC_alloc (tree, heap, m); | |
1141 | for (i = 0; i < n; i++) | |
33b30201 SP |
1142 | { |
1143 | tree type = signed_type_for_types (TREE_TYPE (VEC_index (tree, fna, i)), | |
1144 | TREE_TYPE (VEC_index (tree, fnb, i))); | |
1145 | ||
1146 | VEC_quick_push (tree, ret, | |
1147 | fold_build2 (op, type, | |
b8698a0f | 1148 | VEC_index (tree, fna, i), |
33b30201 SP |
1149 | VEC_index (tree, fnb, i))); |
1150 | } | |
d93817c4 ZD |
1151 | |
1152 | for (; VEC_iterate (tree, fna, i, coef); i++) | |
1153 | VEC_quick_push (tree, ret, | |
33b30201 | 1154 | fold_build2 (op, signed_type_for (TREE_TYPE (coef)), |
d93817c4 ZD |
1155 | coef, integer_zero_node)); |
1156 | for (; VEC_iterate (tree, fnb, i, coef); i++) | |
1157 | VEC_quick_push (tree, ret, | |
33b30201 | 1158 | fold_build2 (op, signed_type_for (TREE_TYPE (coef)), |
d93817c4 ZD |
1159 | integer_zero_node, coef)); |
1160 | ||
1161 | return ret; | |
1162 | } | |
1163 | ||
1164 | /* Returns the sum of affine functions FNA and FNB. */ | |
1165 | ||
1166 | static affine_fn | |
1167 | affine_fn_plus (affine_fn fna, affine_fn fnb) | |
1168 | { | |
1169 | return affine_fn_op (PLUS_EXPR, fna, fnb); | |
1170 | } | |
1171 | ||
1172 | /* Returns the difference of affine functions FNA and FNB. */ | |
1173 | ||
1174 | static affine_fn | |
1175 | affine_fn_minus (affine_fn fna, affine_fn fnb) | |
1176 | { | |
1177 | return affine_fn_op (MINUS_EXPR, fna, fnb); | |
1178 | } | |
1179 | ||
1180 | /* Frees affine function FN. */ | |
1181 | ||
1182 | static void | |
1183 | affine_fn_free (affine_fn fn) | |
1184 | { | |
1185 | VEC_free (tree, heap, fn); | |
1186 | } | |
1187 | ||
86df10e3 SP |
1188 | /* Determine for each subscript in the data dependence relation DDR |
1189 | the distance. */ | |
56cf8686 | 1190 | |
0ff4040e | 1191 | static void |
86df10e3 | 1192 | compute_subscript_distance (struct data_dependence_relation *ddr) |
56cf8686 | 1193 | { |
d93817c4 ZD |
1194 | conflict_function *cf_a, *cf_b; |
1195 | affine_fn fn_a, fn_b, diff; | |
1196 | ||
56cf8686 SP |
1197 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
1198 | { | |
1199 | unsigned int i; | |
b8698a0f | 1200 | |
56cf8686 SP |
1201 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
1202 | { | |
56cf8686 | 1203 | struct subscript *subscript; |
b8698a0f | 1204 | |
56cf8686 | 1205 | subscript = DDR_SUBSCRIPT (ddr, i); |
d93817c4 ZD |
1206 | cf_a = SUB_CONFLICTS_IN_A (subscript); |
1207 | cf_b = SUB_CONFLICTS_IN_B (subscript); | |
86df10e3 | 1208 | |
d93817c4 ZD |
1209 | fn_a = common_affine_function (cf_a); |
1210 | fn_b = common_affine_function (cf_b); | |
1211 | if (!fn_a || !fn_b) | |
86df10e3 | 1212 | { |
d93817c4 ZD |
1213 | SUB_DISTANCE (subscript) = chrec_dont_know; |
1214 | return; | |
86df10e3 | 1215 | } |
d93817c4 | 1216 | diff = affine_fn_minus (fn_a, fn_b); |
b8698a0f | 1217 | |
d93817c4 ZD |
1218 | if (affine_function_constant_p (diff)) |
1219 | SUB_DISTANCE (subscript) = affine_function_base (diff); | |
56cf8686 SP |
1220 | else |
1221 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
d93817c4 ZD |
1222 | |
1223 | affine_fn_free (diff); | |
56cf8686 SP |
1224 | } |
1225 | } | |
1226 | } | |
1227 | ||
d93817c4 ZD |
1228 | /* Returns the conflict function for "unknown". */ |
1229 | ||
1230 | static conflict_function * | |
1231 | conflict_fn_not_known (void) | |
1232 | { | |
1233 | conflict_function *fn = XCNEW (conflict_function); | |
1234 | fn->n = NOT_KNOWN; | |
1235 | ||
1236 | return fn; | |
1237 | } | |
1238 | ||
1239 | /* Returns the conflict function for "independent". */ | |
1240 | ||
1241 | static conflict_function * | |
1242 | conflict_fn_no_dependence (void) | |
1243 | { | |
1244 | conflict_function *fn = XCNEW (conflict_function); | |
1245 | fn->n = NO_DEPENDENCE; | |
1246 | ||
1247 | return fn; | |
1248 | } | |
1249 | ||
3cb960c7 ZD |
1250 | /* Returns true if the address of OBJ is invariant in LOOP. */ |
1251 | ||
1252 | static bool | |
ed7a4b4b | 1253 | object_address_invariant_in_loop_p (const struct loop *loop, const_tree obj) |
3cb960c7 ZD |
1254 | { |
1255 | while (handled_component_p (obj)) | |
1256 | { | |
1257 | if (TREE_CODE (obj) == ARRAY_REF) | |
1258 | { | |
1259 | /* Index of the ARRAY_REF was zeroed in analyze_indices, thus we only | |
1260 | need to check the stride and the lower bound of the reference. */ | |
1261 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1262 | loop->num) | |
1263 | || chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 3), | |
1264 | loop->num)) | |
1265 | return false; | |
1266 | } | |
1267 | else if (TREE_CODE (obj) == COMPONENT_REF) | |
1268 | { | |
1269 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1270 | loop->num)) | |
1271 | return false; | |
1272 | } | |
1273 | obj = TREE_OPERAND (obj, 0); | |
1274 | } | |
1275 | ||
70f34814 RG |
1276 | if (!INDIRECT_REF_P (obj) |
1277 | && TREE_CODE (obj) != MEM_REF) | |
3cb960c7 ZD |
1278 | return true; |
1279 | ||
1280 | return !chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 0), | |
1281 | loop->num); | |
1282 | } | |
1283 | ||
3cb960c7 ZD |
1284 | /* Returns false if we can prove that data references A and B do not alias, |
1285 | true otherwise. */ | |
1286 | ||
f8bf9252 | 1287 | bool |
ed7a4b4b | 1288 | dr_may_alias_p (const struct data_reference *a, const struct data_reference *b) |
3cb960c7 | 1289 | { |
7d36e538 RG |
1290 | tree addr_a = DR_BASE_OBJECT (a); |
1291 | tree addr_b = DR_BASE_OBJECT (b); | |
3cb960c7 | 1292 | |
b0af49c4 | 1293 | if (DR_IS_WRITE (a) && DR_IS_WRITE (b)) |
7d36e538 | 1294 | return refs_output_dependent_p (addr_a, addr_b); |
b0af49c4 | 1295 | else if (DR_IS_READ (a) && DR_IS_WRITE (b)) |
7d36e538 RG |
1296 | return refs_anti_dependent_p (addr_a, addr_b); |
1297 | return refs_may_alias_p (addr_a, addr_b); | |
3cb960c7 ZD |
1298 | } |
1299 | ||
b3924be9 SP |
1300 | static void compute_self_dependence (struct data_dependence_relation *); |
1301 | ||
0ff4040e SP |
1302 | /* Initialize a data dependence relation between data accesses A and |
1303 | B. NB_LOOPS is the number of loops surrounding the references: the | |
1304 | size of the classic distance/direction vectors. */ | |
56cf8686 | 1305 | |
0ff4040e | 1306 | static struct data_dependence_relation * |
b8698a0f | 1307 | initialize_data_dependence_relation (struct data_reference *a, |
0ff4040e | 1308 | struct data_reference *b, |
ba42e045 | 1309 | VEC (loop_p, heap) *loop_nest) |
56cf8686 SP |
1310 | { |
1311 | struct data_dependence_relation *res; | |
0ff4040e | 1312 | unsigned int i; |
b8698a0f | 1313 | |
5ed6ace5 | 1314 | res = XNEW (struct data_dependence_relation); |
56cf8686 SP |
1315 | DDR_A (res) = a; |
1316 | DDR_B (res) = b; | |
3ac57120 | 1317 | DDR_LOOP_NEST (res) = NULL; |
71d5b5e1 | 1318 | DDR_REVERSED_P (res) = false; |
2f470326 JJ |
1319 | DDR_SUBSCRIPTS (res) = NULL; |
1320 | DDR_DIR_VECTS (res) = NULL; | |
1321 | DDR_DIST_VECTS (res) = NULL; | |
56cf8686 | 1322 | |
86a07404 IR |
1323 | if (a == NULL || b == NULL) |
1324 | { | |
b8698a0f | 1325 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 | 1326 | return res; |
b8698a0f | 1327 | } |
86a07404 | 1328 | |
3cb960c7 ZD |
1329 | /* If the data references do not alias, then they are independent. */ |
1330 | if (!dr_may_alias_p (a, b)) | |
86a07404 | 1331 | { |
b8698a0f | 1332 | DDR_ARE_DEPENDENT (res) = chrec_known; |
86a07404 IR |
1333 | return res; |
1334 | } | |
56cf8686 | 1335 | |
b3924be9 SP |
1336 | /* When the references are exactly the same, don't spend time doing |
1337 | the data dependence tests, just initialize the ddr and return. */ | |
1338 | if (operand_equal_p (DR_REF (a), DR_REF (b), 0)) | |
1339 | { | |
1340 | DDR_AFFINE_P (res) = true; | |
1341 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
1342 | DDR_SUBSCRIPTS (res) = VEC_alloc (subscript_p, heap, DR_NUM_DIMENSIONS (a)); | |
1343 | DDR_LOOP_NEST (res) = loop_nest; | |
1344 | DDR_INNER_LOOP (res) = 0; | |
1345 | DDR_SELF_REFERENCE (res) = true; | |
1346 | compute_self_dependence (res); | |
1347 | return res; | |
1348 | } | |
1349 | ||
3cb960c7 ZD |
1350 | /* If the references do not access the same object, we do not know |
1351 | whether they alias or not. */ | |
1352 | if (!operand_equal_p (DR_BASE_OBJECT (a), DR_BASE_OBJECT (b), 0)) | |
56cf8686 | 1353 | { |
b8698a0f | 1354 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1355 | return res; |
1356 | } | |
0ff4040e | 1357 | |
3cb960c7 | 1358 | /* If the base of the object is not invariant in the loop nest, we cannot |
0d52bcc1 | 1359 | analyze it. TODO -- in fact, it would suffice to record that there may |
c80b4100 | 1360 | be arbitrary dependences in the loops where the base object varies. */ |
b8698a0f | 1361 | if (loop_nest |
a70d6342 IR |
1362 | && !object_address_invariant_in_loop_p (VEC_index (loop_p, loop_nest, 0), |
1363 | DR_BASE_OBJECT (a))) | |
86a07404 | 1364 | { |
b8698a0f | 1365 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1366 | return res; |
1367 | } | |
3cb960c7 | 1368 | |
19368333 RG |
1369 | /* If the number of dimensions of the access to not agree we can have |
1370 | a pointer access to a component of the array element type and an | |
1371 | array access while the base-objects are still the same. Punt. */ | |
1372 | if (DR_NUM_DIMENSIONS (a) != DR_NUM_DIMENSIONS (b)) | |
1373 | { | |
1374 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1375 | return res; | |
1376 | } | |
3cb960c7 | 1377 | |
86a07404 IR |
1378 | DDR_AFFINE_P (res) = true; |
1379 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
ebf78a47 | 1380 | DDR_SUBSCRIPTS (res) = VEC_alloc (subscript_p, heap, DR_NUM_DIMENSIONS (a)); |
ba42e045 | 1381 | DDR_LOOP_NEST (res) = loop_nest; |
3d8864c0 | 1382 | DDR_INNER_LOOP (res) = 0; |
b3924be9 | 1383 | DDR_SELF_REFERENCE (res) = false; |
304afda6 | 1384 | |
86a07404 IR |
1385 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1386 | { | |
1387 | struct subscript *subscript; | |
b8698a0f | 1388 | |
5ed6ace5 | 1389 | subscript = XNEW (struct subscript); |
d93817c4 ZD |
1390 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); |
1391 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
86a07404 IR |
1392 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
1393 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
ebf78a47 | 1394 | VEC_safe_push (subscript_p, heap, DDR_SUBSCRIPTS (res), subscript); |
56cf8686 | 1395 | } |
ebf78a47 | 1396 | |
56cf8686 SP |
1397 | return res; |
1398 | } | |
1399 | ||
d93817c4 ZD |
1400 | /* Frees memory used by the conflict function F. */ |
1401 | ||
1402 | static void | |
1403 | free_conflict_function (conflict_function *f) | |
1404 | { | |
1405 | unsigned i; | |
1406 | ||
1407 | if (CF_NONTRIVIAL_P (f)) | |
1408 | { | |
1409 | for (i = 0; i < f->n; i++) | |
1410 | affine_fn_free (f->fns[i]); | |
1411 | } | |
1412 | free (f); | |
1413 | } | |
1414 | ||
1415 | /* Frees memory used by SUBSCRIPTS. */ | |
1416 | ||
1417 | static void | |
1418 | free_subscripts (VEC (subscript_p, heap) *subscripts) | |
1419 | { | |
1420 | unsigned i; | |
1421 | subscript_p s; | |
1422 | ||
ac47786e | 1423 | FOR_EACH_VEC_ELT (subscript_p, subscripts, i, s) |
d93817c4 ZD |
1424 | { |
1425 | free_conflict_function (s->conflicting_iterations_in_a); | |
1426 | free_conflict_function (s->conflicting_iterations_in_b); | |
a0044be5 | 1427 | free (s); |
d93817c4 ZD |
1428 | } |
1429 | VEC_free (subscript_p, heap, subscripts); | |
1430 | } | |
1431 | ||
56cf8686 SP |
1432 | /* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap |
1433 | description. */ | |
1434 | ||
1435 | static inline void | |
b8698a0f | 1436 | finalize_ddr_dependent (struct data_dependence_relation *ddr, |
56cf8686 SP |
1437 | tree chrec) |
1438 | { | |
36d59cf7 DB |
1439 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1440 | { | |
1441 | fprintf (dump_file, "(dependence classified: "); | |
1442 | print_generic_expr (dump_file, chrec, 0); | |
1443 | fprintf (dump_file, ")\n"); | |
1444 | } | |
1445 | ||
b8698a0f | 1446 | DDR_ARE_DEPENDENT (ddr) = chrec; |
d93817c4 | 1447 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
2f470326 | 1448 | DDR_SUBSCRIPTS (ddr) = NULL; |
56cf8686 SP |
1449 | } |
1450 | ||
86df10e3 SP |
1451 | /* The dependence relation DDR cannot be represented by a distance |
1452 | vector. */ | |
1453 | ||
1454 | static inline void | |
1455 | non_affine_dependence_relation (struct data_dependence_relation *ddr) | |
1456 | { | |
1457 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1458 | fprintf (dump_file, "(Dependence relation cannot be represented by distance vector.) \n"); | |
1459 | ||
1460 | DDR_AFFINE_P (ddr) = false; | |
1461 | } | |
1462 | ||
56cf8686 SP |
1463 | \f |
1464 | ||
1465 | /* This section contains the classic Banerjee tests. */ | |
1466 | ||
1467 | /* Returns true iff CHREC_A and CHREC_B are not dependent on any index | |
1468 | variables, i.e., if the ZIV (Zero Index Variable) test is true. */ | |
1469 | ||
1470 | static inline bool | |
ed7a4b4b | 1471 | ziv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1472 | { |
1473 | return (evolution_function_is_constant_p (chrec_a) | |
1474 | && evolution_function_is_constant_p (chrec_b)); | |
1475 | } | |
1476 | ||
1477 | /* Returns true iff CHREC_A and CHREC_B are dependent on an index | |
1478 | variable, i.e., if the SIV (Single Index Variable) test is true. */ | |
1479 | ||
1480 | static bool | |
ed7a4b4b | 1481 | siv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1482 | { |
1483 | if ((evolution_function_is_constant_p (chrec_a) | |
1484 | && evolution_function_is_univariate_p (chrec_b)) | |
1485 | || (evolution_function_is_constant_p (chrec_b) | |
1486 | && evolution_function_is_univariate_p (chrec_a))) | |
1487 | return true; | |
b8698a0f | 1488 | |
56cf8686 SP |
1489 | if (evolution_function_is_univariate_p (chrec_a) |
1490 | && evolution_function_is_univariate_p (chrec_b)) | |
1491 | { | |
1492 | switch (TREE_CODE (chrec_a)) | |
1493 | { | |
1494 | case POLYNOMIAL_CHREC: | |
1495 | switch (TREE_CODE (chrec_b)) | |
1496 | { | |
1497 | case POLYNOMIAL_CHREC: | |
1498 | if (CHREC_VARIABLE (chrec_a) != CHREC_VARIABLE (chrec_b)) | |
1499 | return false; | |
b8698a0f | 1500 | |
56cf8686 SP |
1501 | default: |
1502 | return true; | |
1503 | } | |
b8698a0f | 1504 | |
56cf8686 SP |
1505 | default: |
1506 | return true; | |
1507 | } | |
1508 | } | |
b8698a0f | 1509 | |
56cf8686 SP |
1510 | return false; |
1511 | } | |
1512 | ||
d93817c4 ZD |
1513 | /* Creates a conflict function with N dimensions. The affine functions |
1514 | in each dimension follow. */ | |
1515 | ||
1516 | static conflict_function * | |
1517 | conflict_fn (unsigned n, ...) | |
1518 | { | |
1519 | unsigned i; | |
1520 | conflict_function *ret = XCNEW (conflict_function); | |
1521 | va_list ap; | |
1522 | ||
b39c6706 | 1523 | gcc_assert (0 < n && n <= MAX_DIM); |
d93817c4 | 1524 | va_start(ap, n); |
b8698a0f | 1525 | |
d93817c4 ZD |
1526 | ret->n = n; |
1527 | for (i = 0; i < n; i++) | |
1528 | ret->fns[i] = va_arg (ap, affine_fn); | |
1529 | va_end(ap); | |
1530 | ||
1531 | return ret; | |
1532 | } | |
1533 | ||
1534 | /* Returns constant affine function with value CST. */ | |
1535 | ||
1536 | static affine_fn | |
1537 | affine_fn_cst (tree cst) | |
1538 | { | |
1539 | affine_fn fn = VEC_alloc (tree, heap, 1); | |
1540 | VEC_quick_push (tree, fn, cst); | |
1541 | return fn; | |
1542 | } | |
1543 | ||
1544 | /* Returns affine function with single variable, CST + COEF * x_DIM. */ | |
1545 | ||
1546 | static affine_fn | |
1547 | affine_fn_univar (tree cst, unsigned dim, tree coef) | |
1548 | { | |
1549 | affine_fn fn = VEC_alloc (tree, heap, dim + 1); | |
1550 | unsigned i; | |
1551 | ||
1552 | gcc_assert (dim > 0); | |
1553 | VEC_quick_push (tree, fn, cst); | |
1554 | for (i = 1; i < dim; i++) | |
1555 | VEC_quick_push (tree, fn, integer_zero_node); | |
1556 | VEC_quick_push (tree, fn, coef); | |
1557 | return fn; | |
1558 | } | |
1559 | ||
56cf8686 SP |
1560 | /* Analyze a ZIV (Zero Index Variable) subscript. *OVERLAPS_A and |
1561 | *OVERLAPS_B are initialized to the functions that describe the | |
1562 | relation between the elements accessed twice by CHREC_A and | |
1563 | CHREC_B. For k >= 0, the following property is verified: | |
1564 | ||
1565 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1566 | ||
b8698a0f L |
1567 | static void |
1568 | analyze_ziv_subscript (tree chrec_a, | |
1569 | tree chrec_b, | |
d93817c4 | 1570 | conflict_function **overlaps_a, |
b8698a0f | 1571 | conflict_function **overlaps_b, |
86df10e3 | 1572 | tree *last_conflicts) |
56cf8686 | 1573 | { |
33b30201 | 1574 | tree type, difference; |
0ff4040e | 1575 | dependence_stats.num_ziv++; |
b8698a0f | 1576 | |
56cf8686 SP |
1577 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1578 | fprintf (dump_file, "(analyze_ziv_subscript \n"); | |
33b30201 SP |
1579 | |
1580 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); | |
726a989a RB |
1581 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1582 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1583 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
b8698a0f | 1584 | |
56cf8686 SP |
1585 | switch (TREE_CODE (difference)) |
1586 | { | |
1587 | case INTEGER_CST: | |
1588 | if (integer_zerop (difference)) | |
1589 | { | |
1590 | /* The difference is equal to zero: the accessed index | |
1591 | overlaps for each iteration in the loop. */ | |
d93817c4 ZD |
1592 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
1593 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 | 1594 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1595 | dependence_stats.num_ziv_dependent++; |
56cf8686 SP |
1596 | } |
1597 | else | |
1598 | { | |
1599 | /* The accesses do not overlap. */ | |
d93817c4 ZD |
1600 | *overlaps_a = conflict_fn_no_dependence (); |
1601 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1602 | *last_conflicts = integer_zero_node; |
0ff4040e | 1603 | dependence_stats.num_ziv_independent++; |
56cf8686 SP |
1604 | } |
1605 | break; | |
b8698a0f | 1606 | |
56cf8686 | 1607 | default: |
b8698a0f | 1608 | /* We're not sure whether the indexes overlap. For the moment, |
56cf8686 | 1609 | conservatively answer "don't know". */ |
0ff4040e SP |
1610 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1611 | fprintf (dump_file, "ziv test failed: difference is non-integer.\n"); | |
1612 | ||
d93817c4 ZD |
1613 | *overlaps_a = conflict_fn_not_known (); |
1614 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1615 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1616 | dependence_stats.num_ziv_unimplemented++; |
56cf8686 SP |
1617 | break; |
1618 | } | |
b8698a0f | 1619 | |
56cf8686 SP |
1620 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1621 | fprintf (dump_file, ")\n"); | |
1622 | } | |
1623 | ||
4839cb59 ZD |
1624 | /* Sets NIT to the estimated number of executions of the statements in |
1625 | LOOP. If CONSERVATIVE is true, we must be sure that NIT is at least as | |
1626 | large as the number of iterations. If we have no reliable estimate, | |
1627 | the function returns false, otherwise returns true. */ | |
416f403e | 1628 | |
ac84e05e | 1629 | bool |
4839cb59 ZD |
1630 | estimated_loop_iterations (struct loop *loop, bool conservative, |
1631 | double_int *nit) | |
416f403e | 1632 | { |
e3488283 | 1633 | estimate_numbers_of_iterations_loop (loop, true); |
9bdb685e | 1634 | if (conservative) |
4839cb59 | 1635 | { |
9bdb685e ZD |
1636 | if (!loop->any_upper_bound) |
1637 | return false; | |
4839cb59 | 1638 | |
9bdb685e | 1639 | *nit = loop->nb_iterations_upper_bound; |
4839cb59 | 1640 | } |
9bdb685e | 1641 | else |
946e1bc7 | 1642 | { |
9bdb685e ZD |
1643 | if (!loop->any_estimate) |
1644 | return false; | |
1645 | ||
1646 | *nit = loop->nb_iterations_estimate; | |
946e1bc7 ZD |
1647 | } |
1648 | ||
9bdb685e | 1649 | return true; |
4839cb59 ZD |
1650 | } |
1651 | ||
1652 | /* Similar to estimated_loop_iterations, but returns the estimate only | |
1653 | if it fits to HOST_WIDE_INT. If this is not the case, or the estimate | |
1654 | on the number of iterations of LOOP could not be derived, returns -1. */ | |
1655 | ||
1656 | HOST_WIDE_INT | |
1657 | estimated_loop_iterations_int (struct loop *loop, bool conservative) | |
1658 | { | |
1659 | double_int nit; | |
1660 | HOST_WIDE_INT hwi_nit; | |
1661 | ||
1662 | if (!estimated_loop_iterations (loop, conservative, &nit)) | |
1663 | return -1; | |
1664 | ||
1665 | if (!double_int_fits_in_shwi_p (nit)) | |
1666 | return -1; | |
1667 | hwi_nit = double_int_to_shwi (nit); | |
1668 | ||
1669 | return hwi_nit < 0 ? -1 : hwi_nit; | |
416f403e | 1670 | } |
b8698a0f | 1671 | |
4839cb59 ZD |
1672 | /* Similar to estimated_loop_iterations, but returns the estimate as a tree, |
1673 | and only if it fits to the int type. If this is not the case, or the | |
1674 | estimate on the number of iterations of LOOP could not be derived, returns | |
1675 | chrec_dont_know. */ | |
1676 | ||
1677 | static tree | |
1678 | estimated_loop_iterations_tree (struct loop *loop, bool conservative) | |
1679 | { | |
1680 | double_int nit; | |
1681 | tree type; | |
1682 | ||
1683 | if (!estimated_loop_iterations (loop, conservative, &nit)) | |
1684 | return chrec_dont_know; | |
1685 | ||
1686 | type = lang_hooks.types.type_for_size (INT_TYPE_SIZE, true); | |
1687 | if (!double_int_fits_to_tree_p (type, nit)) | |
1688 | return chrec_dont_know; | |
1689 | ||
1690 | return double_int_to_tree (type, nit); | |
1691 | } | |
1692 | ||
56cf8686 SP |
1693 | /* Analyze a SIV (Single Index Variable) subscript where CHREC_A is a |
1694 | constant, and CHREC_B is an affine function. *OVERLAPS_A and | |
1695 | *OVERLAPS_B are initialized to the functions that describe the | |
1696 | relation between the elements accessed twice by CHREC_A and | |
1697 | CHREC_B. For k >= 0, the following property is verified: | |
1698 | ||
1699 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1700 | ||
1701 | static void | |
b8698a0f | 1702 | analyze_siv_subscript_cst_affine (tree chrec_a, |
56cf8686 | 1703 | tree chrec_b, |
b8698a0f L |
1704 | conflict_function **overlaps_a, |
1705 | conflict_function **overlaps_b, | |
86df10e3 | 1706 | tree *last_conflicts) |
56cf8686 SP |
1707 | { |
1708 | bool value0, value1, value2; | |
33b30201 | 1709 | tree type, difference, tmp; |
e2157b49 | 1710 | |
33b30201 | 1711 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
1712 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1713 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1714 | difference = chrec_fold_minus (type, initial_condition (chrec_b), chrec_a); |
b8698a0f | 1715 | |
56cf8686 SP |
1716 | if (!chrec_is_positive (initial_condition (difference), &value0)) |
1717 | { | |
0ff4040e | 1718 | if (dump_file && (dump_flags & TDF_DETAILS)) |
b8698a0f | 1719 | fprintf (dump_file, "siv test failed: chrec is not positive.\n"); |
0ff4040e SP |
1720 | |
1721 | dependence_stats.num_siv_unimplemented++; | |
d93817c4 ZD |
1722 | *overlaps_a = conflict_fn_not_known (); |
1723 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1724 | *last_conflicts = chrec_dont_know; |
56cf8686 SP |
1725 | return; |
1726 | } | |
1727 | else | |
1728 | { | |
1729 | if (value0 == false) | |
1730 | { | |
1731 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value1)) | |
1732 | { | |
0ff4040e SP |
1733 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1734 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1735 | ||
d93817c4 | 1736 | *overlaps_a = conflict_fn_not_known (); |
b8698a0f | 1737 | *overlaps_b = conflict_fn_not_known (); |
86df10e3 | 1738 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1739 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1740 | return; |
1741 | } | |
1742 | else | |
1743 | { | |
1744 | if (value1 == true) | |
1745 | { | |
b8698a0f | 1746 | /* Example: |
56cf8686 SP |
1747 | chrec_a = 12 |
1748 | chrec_b = {10, +, 1} | |
1749 | */ | |
b8698a0f | 1750 | |
f457cf40 | 1751 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1752 | { |
4839cb59 ZD |
1753 | HOST_WIDE_INT numiter; |
1754 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1755 | |
d93817c4 | 1756 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 SP |
1757 | tmp = fold_build2 (EXACT_DIV_EXPR, type, |
1758 | fold_build1 (ABS_EXPR, type, difference), | |
d93817c4 ZD |
1759 | CHREC_RIGHT (chrec_b)); |
1760 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1761 | *last_conflicts = integer_one_node; |
b8698a0f | 1762 | |
416f403e DB |
1763 | |
1764 | /* Perform weak-zero siv test to see if overlap is | |
1765 | outside the loop bounds. */ | |
fd727b34 | 1766 | numiter = estimated_loop_iterations_int (loop, false); |
416f403e | 1767 | |
4839cb59 ZD |
1768 | if (numiter >= 0 |
1769 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 1770 | { |
d93817c4 ZD |
1771 | free_conflict_function (*overlaps_a); |
1772 | free_conflict_function (*overlaps_b); | |
1773 | *overlaps_a = conflict_fn_no_dependence (); | |
1774 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 1775 | *last_conflicts = integer_zero_node; |
0ff4040e | 1776 | dependence_stats.num_siv_independent++; |
416f403e | 1777 | return; |
b8698a0f | 1778 | } |
0ff4040e | 1779 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
1780 | return; |
1781 | } | |
b8698a0f | 1782 | |
f457cf40 | 1783 | /* When the step does not divide the difference, there are |
56cf8686 SP |
1784 | no overlaps. */ |
1785 | else | |
1786 | { | |
d93817c4 | 1787 | *overlaps_a = conflict_fn_no_dependence (); |
b8698a0f | 1788 | *overlaps_b = conflict_fn_no_dependence (); |
86df10e3 | 1789 | *last_conflicts = integer_zero_node; |
0ff4040e | 1790 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1791 | return; |
1792 | } | |
1793 | } | |
b8698a0f | 1794 | |
56cf8686 SP |
1795 | else |
1796 | { | |
b8698a0f | 1797 | /* Example: |
56cf8686 SP |
1798 | chrec_a = 12 |
1799 | chrec_b = {10, +, -1} | |
b8698a0f | 1800 | |
56cf8686 | 1801 | In this case, chrec_a will not overlap with chrec_b. */ |
d93817c4 ZD |
1802 | *overlaps_a = conflict_fn_no_dependence (); |
1803 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1804 | *last_conflicts = integer_zero_node; |
0ff4040e | 1805 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1806 | return; |
1807 | } | |
1808 | } | |
1809 | } | |
b8698a0f | 1810 | else |
56cf8686 SP |
1811 | { |
1812 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value2)) | |
1813 | { | |
0ff4040e SP |
1814 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1815 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1816 | ||
d93817c4 | 1817 | *overlaps_a = conflict_fn_not_known (); |
b8698a0f | 1818 | *overlaps_b = conflict_fn_not_known (); |
86df10e3 | 1819 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1820 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1821 | return; |
1822 | } | |
1823 | else | |
1824 | { | |
1825 | if (value2 == false) | |
1826 | { | |
b8698a0f | 1827 | /* Example: |
56cf8686 SP |
1828 | chrec_a = 3 |
1829 | chrec_b = {10, +, -1} | |
1830 | */ | |
f457cf40 | 1831 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1832 | { |
4839cb59 ZD |
1833 | HOST_WIDE_INT numiter; |
1834 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1835 | |
d93817c4 | 1836 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 | 1837 | tmp = fold_build2 (EXACT_DIV_EXPR, type, difference, |
d93817c4 ZD |
1838 | CHREC_RIGHT (chrec_b)); |
1839 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1840 | *last_conflicts = integer_one_node; |
416f403e DB |
1841 | |
1842 | /* Perform weak-zero siv test to see if overlap is | |
1843 | outside the loop bounds. */ | |
fd727b34 | 1844 | numiter = estimated_loop_iterations_int (loop, false); |
416f403e | 1845 | |
4839cb59 ZD |
1846 | if (numiter >= 0 |
1847 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 1848 | { |
d93817c4 ZD |
1849 | free_conflict_function (*overlaps_a); |
1850 | free_conflict_function (*overlaps_b); | |
1851 | *overlaps_a = conflict_fn_no_dependence (); | |
1852 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 1853 | *last_conflicts = integer_zero_node; |
0ff4040e | 1854 | dependence_stats.num_siv_independent++; |
416f403e | 1855 | return; |
b8698a0f | 1856 | } |
0ff4040e | 1857 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
1858 | return; |
1859 | } | |
b8698a0f | 1860 | |
4286d8ce | 1861 | /* When the step does not divide the difference, there |
56cf8686 SP |
1862 | are no overlaps. */ |
1863 | else | |
1864 | { | |
d93817c4 | 1865 | *overlaps_a = conflict_fn_no_dependence (); |
b8698a0f | 1866 | *overlaps_b = conflict_fn_no_dependence (); |
86df10e3 | 1867 | *last_conflicts = integer_zero_node; |
0ff4040e | 1868 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1869 | return; |
1870 | } | |
1871 | } | |
1872 | else | |
1873 | { | |
b8698a0f L |
1874 | /* Example: |
1875 | chrec_a = 3 | |
56cf8686 | 1876 | chrec_b = {4, +, 1} |
b8698a0f | 1877 | |
56cf8686 | 1878 | In this case, chrec_a will not overlap with chrec_b. */ |
d93817c4 ZD |
1879 | *overlaps_a = conflict_fn_no_dependence (); |
1880 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1881 | *last_conflicts = integer_zero_node; |
0ff4040e | 1882 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1883 | return; |
1884 | } | |
1885 | } | |
1886 | } | |
1887 | } | |
1888 | } | |
1889 | ||
50300b4c | 1890 | /* Helper recursive function for initializing the matrix A. Returns |
86df10e3 | 1891 | the initial value of CHREC. */ |
56cf8686 | 1892 | |
5b78fc3e | 1893 | static tree |
86df10e3 SP |
1894 | initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) |
1895 | { | |
1896 | gcc_assert (chrec); | |
1897 | ||
5b78fc3e JS |
1898 | switch (TREE_CODE (chrec)) |
1899 | { | |
1900 | case POLYNOMIAL_CHREC: | |
1901 | gcc_assert (TREE_CODE (CHREC_RIGHT (chrec)) == INTEGER_CST); | |
1902 | ||
1903 | A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); | |
1904 | return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); | |
1905 | ||
1906 | case PLUS_EXPR: | |
1907 | case MULT_EXPR: | |
1908 | case MINUS_EXPR: | |
1909 | { | |
1910 | tree op0 = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
1911 | tree op1 = initialize_matrix_A (A, TREE_OPERAND (chrec, 1), index, mult); | |
1912 | ||
1913 | return chrec_fold_op (TREE_CODE (chrec), chrec_type (chrec), op0, op1); | |
1914 | } | |
1915 | ||
1916 | case NOP_EXPR: | |
1917 | { | |
1918 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
726a989a | 1919 | return chrec_convert (chrec_type (chrec), op, NULL); |
5b78fc3e JS |
1920 | } |
1921 | ||
418df9d7 JJ |
1922 | case BIT_NOT_EXPR: |
1923 | { | |
1924 | /* Handle ~X as -1 - X. */ | |
1925 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
1926 | return chrec_fold_op (MINUS_EXPR, chrec_type (chrec), | |
1927 | build_int_cst (TREE_TYPE (chrec), -1), op); | |
1928 | } | |
1929 | ||
5b78fc3e JS |
1930 | case INTEGER_CST: |
1931 | return chrec; | |
a1a5996d | 1932 | |
5b78fc3e JS |
1933 | default: |
1934 | gcc_unreachable (); | |
1935 | return NULL_TREE; | |
1936 | } | |
86df10e3 SP |
1937 | } |
1938 | ||
1939 | #define FLOOR_DIV(x,y) ((x) / (y)) | |
1940 | ||
b8698a0f | 1941 | /* Solves the special case of the Diophantine equation: |
86df10e3 SP |
1942 | | {0, +, STEP_A}_x (OVERLAPS_A) = {0, +, STEP_B}_y (OVERLAPS_B) |
1943 | ||
1944 | Computes the descriptions OVERLAPS_A and OVERLAPS_B. NITER is the | |
1945 | number of iterations that loops X and Y run. The overlaps will be | |
1946 | constructed as evolutions in dimension DIM. */ | |
56cf8686 SP |
1947 | |
1948 | static void | |
b8698a0f | 1949 | compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b, |
d93817c4 | 1950 | affine_fn *overlaps_a, |
b8698a0f | 1951 | affine_fn *overlaps_b, |
86df10e3 SP |
1952 | tree *last_conflicts, int dim) |
1953 | { | |
1954 | if (((step_a > 0 && step_b > 0) | |
1955 | || (step_a < 0 && step_b < 0))) | |
1956 | { | |
1957 | int step_overlaps_a, step_overlaps_b; | |
1958 | int gcd_steps_a_b, last_conflict, tau2; | |
1959 | ||
1960 | gcd_steps_a_b = gcd (step_a, step_b); | |
1961 | step_overlaps_a = step_b / gcd_steps_a_b; | |
1962 | step_overlaps_b = step_a / gcd_steps_a_b; | |
1963 | ||
2c26cbfd SP |
1964 | if (niter > 0) |
1965 | { | |
1966 | tau2 = FLOOR_DIV (niter, step_overlaps_a); | |
1967 | tau2 = MIN (tau2, FLOOR_DIV (niter, step_overlaps_b)); | |
1968 | last_conflict = tau2; | |
1969 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); | |
1970 | } | |
1971 | else | |
1972 | *last_conflicts = chrec_dont_know; | |
86df10e3 | 1973 | |
b8698a0f | 1974 | *overlaps_a = affine_fn_univar (integer_zero_node, dim, |
d93817c4 ZD |
1975 | build_int_cst (NULL_TREE, |
1976 | step_overlaps_a)); | |
b8698a0f L |
1977 | *overlaps_b = affine_fn_univar (integer_zero_node, dim, |
1978 | build_int_cst (NULL_TREE, | |
d93817c4 | 1979 | step_overlaps_b)); |
86df10e3 SP |
1980 | } |
1981 | ||
1982 | else | |
1983 | { | |
d93817c4 ZD |
1984 | *overlaps_a = affine_fn_cst (integer_zero_node); |
1985 | *overlaps_b = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
1986 | *last_conflicts = integer_zero_node; |
1987 | } | |
1988 | } | |
1989 | ||
86df10e3 SP |
1990 | /* Solves the special case of a Diophantine equation where CHREC_A is |
1991 | an affine bivariate function, and CHREC_B is an affine univariate | |
b8698a0f | 1992 | function. For example, |
86df10e3 SP |
1993 | |
1994 | | {{0, +, 1}_x, +, 1335}_y = {0, +, 1336}_z | |
b8698a0f L |
1995 | |
1996 | has the following overlapping functions: | |
86df10e3 SP |
1997 | |
1998 | | x (t, u, v) = {{0, +, 1336}_t, +, 1}_v | |
1999 | | y (t, u, v) = {{0, +, 1336}_u, +, 1}_v | |
2000 | | z (t, u, v) = {{{0, +, 1}_t, +, 1335}_u, +, 1}_v | |
2001 | ||
35fd3193 | 2002 | FORNOW: This is a specialized implementation for a case occurring in |
86df10e3 SP |
2003 | a common benchmark. Implement the general algorithm. */ |
2004 | ||
2005 | static void | |
b8698a0f | 2006 | compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b, |
d93817c4 | 2007 | conflict_function **overlaps_a, |
b8698a0f | 2008 | conflict_function **overlaps_b, |
86df10e3 | 2009 | tree *last_conflicts) |
56cf8686 | 2010 | { |
86df10e3 SP |
2011 | bool xz_p, yz_p, xyz_p; |
2012 | int step_x, step_y, step_z; | |
4839cb59 | 2013 | HOST_WIDE_INT niter_x, niter_y, niter_z, niter; |
d93817c4 ZD |
2014 | affine_fn overlaps_a_xz, overlaps_b_xz; |
2015 | affine_fn overlaps_a_yz, overlaps_b_yz; | |
2016 | affine_fn overlaps_a_xyz, overlaps_b_xyz; | |
2017 | affine_fn ova1, ova2, ovb; | |
2018 | tree last_conflicts_xz, last_conflicts_yz, last_conflicts_xyz; | |
86df10e3 | 2019 | |
6b6fa4e9 SP |
2020 | step_x = int_cst_value (CHREC_RIGHT (CHREC_LEFT (chrec_a))); |
2021 | step_y = int_cst_value (CHREC_RIGHT (chrec_a)); | |
2022 | step_z = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2023 | |
b8698a0f | 2024 | niter_x = |
fd727b34 SP |
2025 | estimated_loop_iterations_int (get_chrec_loop (CHREC_LEFT (chrec_a)), |
2026 | false); | |
2027 | niter_y = estimated_loop_iterations_int (get_chrec_loop (chrec_a), false); | |
2028 | niter_z = estimated_loop_iterations_int (get_chrec_loop (chrec_b), false); | |
b8698a0f | 2029 | |
4839cb59 | 2030 | if (niter_x < 0 || niter_y < 0 || niter_z < 0) |
86df10e3 | 2031 | { |
0ff4040e SP |
2032 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2033 | fprintf (dump_file, "overlap steps test failed: no iteration counts.\n"); | |
b8698a0f | 2034 | |
d93817c4 ZD |
2035 | *overlaps_a = conflict_fn_not_known (); |
2036 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2037 | *last_conflicts = chrec_dont_know; |
2038 | return; | |
2039 | } | |
2040 | ||
86df10e3 SP |
2041 | niter = MIN (niter_x, niter_z); |
2042 | compute_overlap_steps_for_affine_univar (niter, step_x, step_z, | |
2043 | &overlaps_a_xz, | |
2044 | &overlaps_b_xz, | |
2045 | &last_conflicts_xz, 1); | |
2046 | niter = MIN (niter_y, niter_z); | |
2047 | compute_overlap_steps_for_affine_univar (niter, step_y, step_z, | |
2048 | &overlaps_a_yz, | |
2049 | &overlaps_b_yz, | |
2050 | &last_conflicts_yz, 2); | |
2051 | niter = MIN (niter_x, niter_z); | |
2052 | niter = MIN (niter_y, niter); | |
2053 | compute_overlap_steps_for_affine_univar (niter, step_x + step_y, step_z, | |
2054 | &overlaps_a_xyz, | |
2055 | &overlaps_b_xyz, | |
2056 | &last_conflicts_xyz, 3); | |
2057 | ||
2058 | xz_p = !integer_zerop (last_conflicts_xz); | |
2059 | yz_p = !integer_zerop (last_conflicts_yz); | |
2060 | xyz_p = !integer_zerop (last_conflicts_xyz); | |
2061 | ||
2062 | if (xz_p || yz_p || xyz_p) | |
2063 | { | |
d93817c4 ZD |
2064 | ova1 = affine_fn_cst (integer_zero_node); |
2065 | ova2 = affine_fn_cst (integer_zero_node); | |
2066 | ovb = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
2067 | if (xz_p) |
2068 | { | |
d93817c4 ZD |
2069 | affine_fn t0 = ova1; |
2070 | affine_fn t2 = ovb; | |
2071 | ||
2072 | ova1 = affine_fn_plus (ova1, overlaps_a_xz); | |
2073 | ovb = affine_fn_plus (ovb, overlaps_b_xz); | |
2074 | affine_fn_free (t0); | |
2075 | affine_fn_free (t2); | |
86df10e3 SP |
2076 | *last_conflicts = last_conflicts_xz; |
2077 | } | |
2078 | if (yz_p) | |
2079 | { | |
d93817c4 ZD |
2080 | affine_fn t0 = ova2; |
2081 | affine_fn t2 = ovb; | |
2082 | ||
2083 | ova2 = affine_fn_plus (ova2, overlaps_a_yz); | |
2084 | ovb = affine_fn_plus (ovb, overlaps_b_yz); | |
2085 | affine_fn_free (t0); | |
2086 | affine_fn_free (t2); | |
86df10e3 SP |
2087 | *last_conflicts = last_conflicts_yz; |
2088 | } | |
2089 | if (xyz_p) | |
2090 | { | |
d93817c4 ZD |
2091 | affine_fn t0 = ova1; |
2092 | affine_fn t2 = ova2; | |
2093 | affine_fn t4 = ovb; | |
2094 | ||
2095 | ova1 = affine_fn_plus (ova1, overlaps_a_xyz); | |
2096 | ova2 = affine_fn_plus (ova2, overlaps_a_xyz); | |
2097 | ovb = affine_fn_plus (ovb, overlaps_b_xyz); | |
2098 | affine_fn_free (t0); | |
2099 | affine_fn_free (t2); | |
2100 | affine_fn_free (t4); | |
86df10e3 SP |
2101 | *last_conflicts = last_conflicts_xyz; |
2102 | } | |
d93817c4 ZD |
2103 | *overlaps_a = conflict_fn (2, ova1, ova2); |
2104 | *overlaps_b = conflict_fn (1, ovb); | |
86df10e3 SP |
2105 | } |
2106 | else | |
2107 | { | |
d93817c4 ZD |
2108 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2109 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 SP |
2110 | *last_conflicts = integer_zero_node; |
2111 | } | |
d93817c4 ZD |
2112 | |
2113 | affine_fn_free (overlaps_a_xz); | |
2114 | affine_fn_free (overlaps_b_xz); | |
2115 | affine_fn_free (overlaps_a_yz); | |
2116 | affine_fn_free (overlaps_b_yz); | |
2117 | affine_fn_free (overlaps_a_xyz); | |
2118 | affine_fn_free (overlaps_b_xyz); | |
56cf8686 SP |
2119 | } |
2120 | ||
b305e3da SP |
2121 | /* Copy the elements of vector VEC1 with length SIZE to VEC2. */ |
2122 | ||
2123 | static void | |
2124 | lambda_vector_copy (lambda_vector vec1, lambda_vector vec2, | |
2125 | int size) | |
2126 | { | |
2127 | memcpy (vec2, vec1, size * sizeof (*vec1)); | |
2128 | } | |
2129 | ||
2130 | /* Copy the elements of M x N matrix MAT1 to MAT2. */ | |
2131 | ||
2132 | static void | |
2133 | lambda_matrix_copy (lambda_matrix mat1, lambda_matrix mat2, | |
2134 | int m, int n) | |
2135 | { | |
2136 | int i; | |
2137 | ||
2138 | for (i = 0; i < m; i++) | |
2139 | lambda_vector_copy (mat1[i], mat2[i], n); | |
2140 | } | |
2141 | ||
2142 | /* Store the N x N identity matrix in MAT. */ | |
2143 | ||
2144 | static void | |
2145 | lambda_matrix_id (lambda_matrix mat, int size) | |
2146 | { | |
2147 | int i, j; | |
2148 | ||
2149 | for (i = 0; i < size; i++) | |
2150 | for (j = 0; j < size; j++) | |
2151 | mat[i][j] = (i == j) ? 1 : 0; | |
2152 | } | |
2153 | ||
2154 | /* Return the first nonzero element of vector VEC1 between START and N. | |
2155 | We must have START <= N. Returns N if VEC1 is the zero vector. */ | |
2156 | ||
2157 | static int | |
2158 | lambda_vector_first_nz (lambda_vector vec1, int n, int start) | |
2159 | { | |
2160 | int j = start; | |
2161 | while (j < n && vec1[j] == 0) | |
2162 | j++; | |
2163 | return j; | |
2164 | } | |
2165 | ||
2166 | /* Add a multiple of row R1 of matrix MAT with N columns to row R2: | |
2167 | R2 = R2 + CONST1 * R1. */ | |
2168 | ||
2169 | static void | |
2170 | lambda_matrix_row_add (lambda_matrix mat, int n, int r1, int r2, int const1) | |
2171 | { | |
2172 | int i; | |
2173 | ||
2174 | if (const1 == 0) | |
2175 | return; | |
2176 | ||
2177 | for (i = 0; i < n; i++) | |
2178 | mat[r2][i] += const1 * mat[r1][i]; | |
2179 | } | |
2180 | ||
2181 | /* Swap rows R1 and R2 in matrix MAT. */ | |
2182 | ||
2183 | static void | |
2184 | lambda_matrix_row_exchange (lambda_matrix mat, int r1, int r2) | |
2185 | { | |
2186 | lambda_vector row; | |
2187 | ||
2188 | row = mat[r1]; | |
2189 | mat[r1] = mat[r2]; | |
2190 | mat[r2] = row; | |
2191 | } | |
2192 | ||
2193 | /* Multiply vector VEC1 of length SIZE by a constant CONST1, | |
2194 | and store the result in VEC2. */ | |
2195 | ||
2196 | static void | |
2197 | lambda_vector_mult_const (lambda_vector vec1, lambda_vector vec2, | |
2198 | int size, int const1) | |
2199 | { | |
2200 | int i; | |
2201 | ||
2202 | if (const1 == 0) | |
2203 | lambda_vector_clear (vec2, size); | |
2204 | else | |
2205 | for (i = 0; i < size; i++) | |
2206 | vec2[i] = const1 * vec1[i]; | |
2207 | } | |
2208 | ||
2209 | /* Negate vector VEC1 with length SIZE and store it in VEC2. */ | |
2210 | ||
2211 | static void | |
2212 | lambda_vector_negate (lambda_vector vec1, lambda_vector vec2, | |
2213 | int size) | |
2214 | { | |
2215 | lambda_vector_mult_const (vec1, vec2, size, -1); | |
2216 | } | |
2217 | ||
2218 | /* Negate row R1 of matrix MAT which has N columns. */ | |
2219 | ||
2220 | static void | |
2221 | lambda_matrix_row_negate (lambda_matrix mat, int n, int r1) | |
2222 | { | |
2223 | lambda_vector_negate (mat[r1], mat[r1], n); | |
2224 | } | |
2225 | ||
2226 | /* Return true if two vectors are equal. */ | |
2227 | ||
2228 | static bool | |
2229 | lambda_vector_equal (lambda_vector vec1, lambda_vector vec2, int size) | |
2230 | { | |
2231 | int i; | |
2232 | for (i = 0; i < size; i++) | |
2233 | if (vec1[i] != vec2[i]) | |
2234 | return false; | |
2235 | return true; | |
2236 | } | |
2237 | ||
2238 | /* Given an M x N integer matrix A, this function determines an M x | |
2239 | M unimodular matrix U, and an M x N echelon matrix S such that | |
2240 | "U.A = S". This decomposition is also known as "right Hermite". | |
2241 | ||
2242 | Ref: Algorithm 2.1 page 33 in "Loop Transformations for | |
2243 | Restructuring Compilers" Utpal Banerjee. */ | |
2244 | ||
2245 | static void | |
2246 | lambda_matrix_right_hermite (lambda_matrix A, int m, int n, | |
2247 | lambda_matrix S, lambda_matrix U) | |
2248 | { | |
2249 | int i, j, i0 = 0; | |
2250 | ||
2251 | lambda_matrix_copy (A, S, m, n); | |
2252 | lambda_matrix_id (U, m); | |
2253 | ||
2254 | for (j = 0; j < n; j++) | |
2255 | { | |
2256 | if (lambda_vector_first_nz (S[j], m, i0) < m) | |
2257 | { | |
2258 | ++i0; | |
2259 | for (i = m - 1; i >= i0; i--) | |
2260 | { | |
2261 | while (S[i][j] != 0) | |
2262 | { | |
2263 | int sigma, factor, a, b; | |
2264 | ||
2265 | a = S[i-1][j]; | |
2266 | b = S[i][j]; | |
2267 | sigma = (a * b < 0) ? -1: 1; | |
2268 | a = abs (a); | |
2269 | b = abs (b); | |
2270 | factor = sigma * (a / b); | |
2271 | ||
2272 | lambda_matrix_row_add (S, n, i, i-1, -factor); | |
2273 | lambda_matrix_row_exchange (S, i, i-1); | |
2274 | ||
2275 | lambda_matrix_row_add (U, m, i, i-1, -factor); | |
2276 | lambda_matrix_row_exchange (U, i, i-1); | |
2277 | } | |
2278 | } | |
2279 | } | |
2280 | } | |
2281 | } | |
2282 | ||
56cf8686 | 2283 | /* Determines the overlapping elements due to accesses CHREC_A and |
0ff4040e SP |
2284 | CHREC_B, that are affine functions. This function cannot handle |
2285 | symbolic evolution functions, ie. when initial conditions are | |
2286 | parameters, because it uses lambda matrices of integers. */ | |
56cf8686 SP |
2287 | |
2288 | static void | |
b8698a0f | 2289 | analyze_subscript_affine_affine (tree chrec_a, |
56cf8686 | 2290 | tree chrec_b, |
b8698a0f L |
2291 | conflict_function **overlaps_a, |
2292 | conflict_function **overlaps_b, | |
86df10e3 | 2293 | tree *last_conflicts) |
56cf8686 | 2294 | { |
86df10e3 | 2295 | unsigned nb_vars_a, nb_vars_b, dim; |
fd727b34 | 2296 | HOST_WIDE_INT init_a, init_b, gamma, gcd_alpha_beta; |
86df10e3 | 2297 | lambda_matrix A, U, S; |
f873b205 | 2298 | struct obstack scratch_obstack; |
86df10e3 | 2299 | |
e2157b49 | 2300 | if (eq_evolutions_p (chrec_a, chrec_b)) |
416f403e | 2301 | { |
e2157b49 SP |
2302 | /* The accessed index overlaps for each iteration in the |
2303 | loop. */ | |
d93817c4 ZD |
2304 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2305 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
416f403e DB |
2306 | *last_conflicts = chrec_dont_know; |
2307 | return; | |
2308 | } | |
56cf8686 SP |
2309 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2310 | fprintf (dump_file, "(analyze_subscript_affine_affine \n"); | |
b8698a0f | 2311 | |
56cf8686 SP |
2312 | /* For determining the initial intersection, we have to solve a |
2313 | Diophantine equation. This is the most time consuming part. | |
b8698a0f | 2314 | |
56cf8686 SP |
2315 | For answering to the question: "Is there a dependence?" we have |
2316 | to prove that there exists a solution to the Diophantine | |
2317 | equation, and that the solution is in the iteration domain, | |
89dbed81 | 2318 | i.e. the solution is positive or zero, and that the solution |
56cf8686 SP |
2319 | happens before the upper bound loop.nb_iterations. Otherwise |
2320 | there is no dependence. This function outputs a description of | |
2321 | the iterations that hold the intersections. */ | |
2322 | ||
86df10e3 SP |
2323 | nb_vars_a = nb_vars_in_chrec (chrec_a); |
2324 | nb_vars_b = nb_vars_in_chrec (chrec_b); | |
2325 | ||
f873b205 LB |
2326 | gcc_obstack_init (&scratch_obstack); |
2327 | ||
86df10e3 | 2328 | dim = nb_vars_a + nb_vars_b; |
f873b205 LB |
2329 | U = lambda_matrix_new (dim, dim, &scratch_obstack); |
2330 | A = lambda_matrix_new (dim, 1, &scratch_obstack); | |
2331 | S = lambda_matrix_new (dim, 1, &scratch_obstack); | |
86df10e3 | 2332 | |
5b78fc3e JS |
2333 | init_a = int_cst_value (initialize_matrix_A (A, chrec_a, 0, 1)); |
2334 | init_b = int_cst_value (initialize_matrix_A (A, chrec_b, nb_vars_a, -1)); | |
86df10e3 SP |
2335 | gamma = init_b - init_a; |
2336 | ||
2337 | /* Don't do all the hard work of solving the Diophantine equation | |
b8698a0f | 2338 | when we already know the solution: for example, |
86df10e3 SP |
2339 | | {3, +, 1}_1 |
2340 | | {3, +, 4}_2 | |
2341 | | gamma = 3 - 3 = 0. | |
b8698a0f | 2342 | Then the first overlap occurs during the first iterations: |
86df10e3 SP |
2343 | | {3, +, 1}_1 ({0, +, 4}_x) = {3, +, 4}_2 ({0, +, 1}_x) |
2344 | */ | |
2345 | if (gamma == 0) | |
56cf8686 | 2346 | { |
86df10e3 | 2347 | if (nb_vars_a == 1 && nb_vars_b == 1) |
56cf8686 | 2348 | { |
fd727b34 | 2349 | HOST_WIDE_INT step_a, step_b; |
4839cb59 | 2350 | HOST_WIDE_INT niter, niter_a, niter_b; |
d93817c4 | 2351 | affine_fn ova, ovb; |
86df10e3 | 2352 | |
fd727b34 SP |
2353 | niter_a = estimated_loop_iterations_int (get_chrec_loop (chrec_a), |
2354 | false); | |
2355 | niter_b = estimated_loop_iterations_int (get_chrec_loop (chrec_b), | |
2356 | false); | |
86df10e3 | 2357 | niter = MIN (niter_a, niter_b); |
6b6fa4e9 SP |
2358 | step_a = int_cst_value (CHREC_RIGHT (chrec_a)); |
2359 | step_b = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2360 | |
b8698a0f L |
2361 | compute_overlap_steps_for_affine_univar (niter, step_a, step_b, |
2362 | &ova, &ovb, | |
86df10e3 | 2363 | last_conflicts, 1); |
d93817c4 ZD |
2364 | *overlaps_a = conflict_fn (1, ova); |
2365 | *overlaps_b = conflict_fn (1, ovb); | |
56cf8686 | 2366 | } |
86df10e3 SP |
2367 | |
2368 | else if (nb_vars_a == 2 && nb_vars_b == 1) | |
2369 | compute_overlap_steps_for_affine_1_2 | |
2370 | (chrec_a, chrec_b, overlaps_a, overlaps_b, last_conflicts); | |
2371 | ||
2372 | else if (nb_vars_a == 1 && nb_vars_b == 2) | |
2373 | compute_overlap_steps_for_affine_1_2 | |
2374 | (chrec_b, chrec_a, overlaps_b, overlaps_a, last_conflicts); | |
2375 | ||
2376 | else | |
56cf8686 | 2377 | { |
0ff4040e SP |
2378 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2379 | fprintf (dump_file, "affine-affine test failed: too many variables.\n"); | |
d93817c4 ZD |
2380 | *overlaps_a = conflict_fn_not_known (); |
2381 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2382 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2383 | } |
0ff4040e | 2384 | goto end_analyze_subs_aa; |
86df10e3 SP |
2385 | } |
2386 | ||
2387 | /* U.A = S */ | |
2388 | lambda_matrix_right_hermite (A, dim, 1, S, U); | |
2389 | ||
2390 | if (S[0][0] < 0) | |
2391 | { | |
2392 | S[0][0] *= -1; | |
2393 | lambda_matrix_row_negate (U, dim, 0); | |
2394 | } | |
2395 | gcd_alpha_beta = S[0][0]; | |
2396 | ||
ba42e045 SP |
2397 | /* Something went wrong: for example in {1, +, 0}_5 vs. {0, +, 0}_5, |
2398 | but that is a quite strange case. Instead of ICEing, answer | |
2399 | don't know. */ | |
2400 | if (gcd_alpha_beta == 0) | |
2401 | { | |
d93817c4 ZD |
2402 | *overlaps_a = conflict_fn_not_known (); |
2403 | *overlaps_b = conflict_fn_not_known (); | |
ba42e045 SP |
2404 | *last_conflicts = chrec_dont_know; |
2405 | goto end_analyze_subs_aa; | |
2406 | } | |
2407 | ||
86df10e3 SP |
2408 | /* The classic "gcd-test". */ |
2409 | if (!int_divides_p (gcd_alpha_beta, gamma)) | |
2410 | { | |
2411 | /* The "gcd-test" has determined that there is no integer | |
2412 | solution, i.e. there is no dependence. */ | |
d93817c4 ZD |
2413 | *overlaps_a = conflict_fn_no_dependence (); |
2414 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 SP |
2415 | *last_conflicts = integer_zero_node; |
2416 | } | |
2417 | ||
2418 | /* Both access functions are univariate. This includes SIV and MIV cases. */ | |
2419 | else if (nb_vars_a == 1 && nb_vars_b == 1) | |
2420 | { | |
2421 | /* Both functions should have the same evolution sign. */ | |
2422 | if (((A[0][0] > 0 && -A[1][0] > 0) | |
2423 | || (A[0][0] < 0 && -A[1][0] < 0))) | |
56cf8686 SP |
2424 | { |
2425 | /* The solutions are given by: | |
b8698a0f | 2426 | | |
86df10e3 SP |
2427 | | [GAMMA/GCD_ALPHA_BETA t].[u11 u12] = [x0] |
2428 | | [u21 u22] [y0] | |
b8698a0f | 2429 | |
56cf8686 | 2430 | For a given integer t. Using the following variables, |
b8698a0f | 2431 | |
56cf8686 SP |
2432 | | i0 = u11 * gamma / gcd_alpha_beta |
2433 | | j0 = u12 * gamma / gcd_alpha_beta | |
2434 | | i1 = u21 | |
2435 | | j1 = u22 | |
b8698a0f | 2436 | |
56cf8686 | 2437 | the solutions are: |
b8698a0f L |
2438 | |
2439 | | x0 = i0 + i1 * t, | |
86df10e3 | 2440 | | y0 = j0 + j1 * t. */ |
2c26cbfd | 2441 | HOST_WIDE_INT i0, j0, i1, j1; |
86df10e3 SP |
2442 | |
2443 | i0 = U[0][0] * gamma / gcd_alpha_beta; | |
2444 | j0 = U[0][1] * gamma / gcd_alpha_beta; | |
2445 | i1 = U[1][0]; | |
2446 | j1 = U[1][1]; | |
2447 | ||
2448 | if ((i1 == 0 && i0 < 0) | |
2449 | || (j1 == 0 && j0 < 0)) | |
56cf8686 | 2450 | { |
b8698a0f L |
2451 | /* There is no solution. |
2452 | FIXME: The case "i0 > nb_iterations, j0 > nb_iterations" | |
2453 | falls in here, but for the moment we don't look at the | |
56cf8686 | 2454 | upper bound of the iteration domain. */ |
d93817c4 ZD |
2455 | *overlaps_a = conflict_fn_no_dependence (); |
2456 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2457 | *last_conflicts = integer_zero_node; |
2c26cbfd | 2458 | goto end_analyze_subs_aa; |
86df10e3 SP |
2459 | } |
2460 | ||
2c26cbfd | 2461 | if (i1 > 0 && j1 > 0) |
56cf8686 | 2462 | { |
2c26cbfd SP |
2463 | HOST_WIDE_INT niter_a = estimated_loop_iterations_int |
2464 | (get_chrec_loop (chrec_a), false); | |
2465 | HOST_WIDE_INT niter_b = estimated_loop_iterations_int | |
2466 | (get_chrec_loop (chrec_b), false); | |
2467 | HOST_WIDE_INT niter = MIN (niter_a, niter_b); | |
2468 | ||
2469 | /* (X0, Y0) is a solution of the Diophantine equation: | |
2470 | "chrec_a (X0) = chrec_b (Y0)". */ | |
2471 | HOST_WIDE_INT tau1 = MAX (CEIL (-i0, i1), | |
2472 | CEIL (-j0, j1)); | |
2473 | HOST_WIDE_INT x0 = i1 * tau1 + i0; | |
2474 | HOST_WIDE_INT y0 = j1 * tau1 + j0; | |
2475 | ||
2476 | /* (X1, Y1) is the smallest positive solution of the eq | |
2477 | "chrec_a (X1) = chrec_b (Y1)", i.e. this is where the | |
2478 | first conflict occurs. */ | |
2479 | HOST_WIDE_INT min_multiple = MIN (x0 / i1, y0 / j1); | |
2480 | HOST_WIDE_INT x1 = x0 - i1 * min_multiple; | |
2481 | HOST_WIDE_INT y1 = y0 - j1 * min_multiple; | |
2482 | ||
2483 | if (niter > 0) | |
56cf8686 | 2484 | { |
2c26cbfd SP |
2485 | HOST_WIDE_INT tau2 = MIN (FLOOR_DIV (niter - i0, i1), |
2486 | FLOOR_DIV (niter - j0, j1)); | |
2487 | HOST_WIDE_INT last_conflict = tau2 - (x1 - i0)/i1; | |
86df10e3 | 2488 | |
2c26cbfd SP |
2489 | /* If the overlap occurs outside of the bounds of the |
2490 | loop, there is no dependence. */ | |
9e517d61 | 2491 | if (x1 >= niter || y1 >= niter) |
56cf8686 | 2492 | { |
2c26cbfd SP |
2493 | *overlaps_a = conflict_fn_no_dependence (); |
2494 | *overlaps_b = conflict_fn_no_dependence (); | |
2495 | *last_conflicts = integer_zero_node; | |
2496 | goto end_analyze_subs_aa; | |
56cf8686 SP |
2497 | } |
2498 | else | |
2c26cbfd | 2499 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); |
56cf8686 | 2500 | } |
56cf8686 | 2501 | else |
2c26cbfd SP |
2502 | *last_conflicts = chrec_dont_know; |
2503 | ||
2504 | *overlaps_a | |
2505 | = conflict_fn (1, | |
2506 | affine_fn_univar (build_int_cst (NULL_TREE, x1), | |
2507 | 1, | |
2508 | build_int_cst (NULL_TREE, i1))); | |
2509 | *overlaps_b | |
2510 | = conflict_fn (1, | |
2511 | affine_fn_univar (build_int_cst (NULL_TREE, y1), | |
2512 | 1, | |
2513 | build_int_cst (NULL_TREE, j1))); | |
2514 | } | |
2515 | else | |
2516 | { | |
2517 | /* FIXME: For the moment, the upper bound of the | |
2518 | iteration domain for i and j is not checked. */ | |
2519 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2520 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
2521 | *overlaps_a = conflict_fn_not_known (); | |
2522 | *overlaps_b = conflict_fn_not_known (); | |
2523 | *last_conflicts = chrec_dont_know; | |
56cf8686 SP |
2524 | } |
2525 | } | |
86df10e3 SP |
2526 | else |
2527 | { | |
0ff4040e SP |
2528 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2529 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2530 | *overlaps_a = conflict_fn_not_known (); |
2531 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2532 | *last_conflicts = chrec_dont_know; |
2533 | } | |
56cf8686 | 2534 | } |
56cf8686 SP |
2535 | else |
2536 | { | |
0ff4040e SP |
2537 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2538 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2539 | *overlaps_a = conflict_fn_not_known (); |
2540 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2541 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2542 | } |
86df10e3 | 2543 | |
b8698a0f | 2544 | end_analyze_subs_aa: |
f873b205 | 2545 | obstack_free (&scratch_obstack, NULL); |
56cf8686 SP |
2546 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2547 | { | |
2548 | fprintf (dump_file, " (overlaps_a = "); | |
d93817c4 | 2549 | dump_conflict_function (dump_file, *overlaps_a); |
56cf8686 | 2550 | fprintf (dump_file, ")\n (overlaps_b = "); |
d93817c4 | 2551 | dump_conflict_function (dump_file, *overlaps_b); |
56cf8686 | 2552 | fprintf (dump_file, ")\n"); |
0ff4040e | 2553 | fprintf (dump_file, ")\n"); |
56cf8686 | 2554 | } |
0ff4040e SP |
2555 | } |
2556 | ||
2557 | /* Returns true when analyze_subscript_affine_affine can be used for | |
2558 | determining the dependence relation between chrec_a and chrec_b, | |
2559 | that contain symbols. This function modifies chrec_a and chrec_b | |
2560 | such that the analysis result is the same, and such that they don't | |
b8698a0f | 2561 | contain symbols, and then can safely be passed to the analyzer. |
0ff4040e SP |
2562 | |
2563 | Example: The analysis of the following tuples of evolutions produce | |
2564 | the same results: {x+1, +, 1}_1 vs. {x+3, +, 1}_1, and {-2, +, 1}_1 | |
2565 | vs. {0, +, 1}_1 | |
b8698a0f | 2566 | |
0ff4040e SP |
2567 | {x+1, +, 1}_1 ({2, +, 1}_1) = {x+3, +, 1}_1 ({0, +, 1}_1) |
2568 | {-2, +, 1}_1 ({2, +, 1}_1) = {0, +, 1}_1 ({0, +, 1}_1) | |
2569 | */ | |
2570 | ||
2571 | static bool | |
2572 | can_use_analyze_subscript_affine_affine (tree *chrec_a, tree *chrec_b) | |
2573 | { | |
16a2acea | 2574 | tree diff, type, left_a, left_b, right_b; |
0ff4040e SP |
2575 | |
2576 | if (chrec_contains_symbols (CHREC_RIGHT (*chrec_a)) | |
2577 | || chrec_contains_symbols (CHREC_RIGHT (*chrec_b))) | |
2578 | /* FIXME: For the moment not handled. Might be refined later. */ | |
2579 | return false; | |
2580 | ||
16a2acea SP |
2581 | type = chrec_type (*chrec_a); |
2582 | left_a = CHREC_LEFT (*chrec_a); | |
726a989a | 2583 | left_b = chrec_convert (type, CHREC_LEFT (*chrec_b), NULL); |
16a2acea SP |
2584 | diff = chrec_fold_minus (type, left_a, left_b); |
2585 | ||
0ff4040e SP |
2586 | if (!evolution_function_is_constant_p (diff)) |
2587 | return false; | |
2588 | ||
56cf8686 | 2589 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e SP |
2590 | fprintf (dump_file, "can_use_subscript_aff_aff_for_symbolic \n"); |
2591 | ||
b8698a0f | 2592 | *chrec_a = build_polynomial_chrec (CHREC_VARIABLE (*chrec_a), |
0ff4040e | 2593 | diff, CHREC_RIGHT (*chrec_a)); |
726a989a | 2594 | right_b = chrec_convert (type, CHREC_RIGHT (*chrec_b), NULL); |
0ff4040e | 2595 | *chrec_b = build_polynomial_chrec (CHREC_VARIABLE (*chrec_b), |
dc61cc6b | 2596 | build_int_cst (type, 0), |
16a2acea | 2597 | right_b); |
0ff4040e | 2598 | return true; |
56cf8686 SP |
2599 | } |
2600 | ||
2601 | /* Analyze a SIV (Single Index Variable) subscript. *OVERLAPS_A and | |
2602 | *OVERLAPS_B are initialized to the functions that describe the | |
2603 | relation between the elements accessed twice by CHREC_A and | |
2604 | CHREC_B. For k >= 0, the following property is verified: | |
2605 | ||
2606 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2607 | ||
2608 | static void | |
b8698a0f | 2609 | analyze_siv_subscript (tree chrec_a, |
56cf8686 | 2610 | tree chrec_b, |
b8698a0f L |
2611 | conflict_function **overlaps_a, |
2612 | conflict_function **overlaps_b, | |
5b78fc3e JS |
2613 | tree *last_conflicts, |
2614 | int loop_nest_num) | |
56cf8686 | 2615 | { |
0ff4040e | 2616 | dependence_stats.num_siv++; |
b8698a0f | 2617 | |
56cf8686 SP |
2618 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2619 | fprintf (dump_file, "(analyze_siv_subscript \n"); | |
b8698a0f | 2620 | |
56cf8686 | 2621 | if (evolution_function_is_constant_p (chrec_a) |
5b78fc3e | 2622 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) |
b8698a0f | 2623 | analyze_siv_subscript_cst_affine (chrec_a, chrec_b, |
86df10e3 | 2624 | overlaps_a, overlaps_b, last_conflicts); |
b8698a0f | 2625 | |
5b78fc3e | 2626 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
56cf8686 | 2627 | && evolution_function_is_constant_p (chrec_b)) |
b8698a0f | 2628 | analyze_siv_subscript_cst_affine (chrec_b, chrec_a, |
86df10e3 | 2629 | overlaps_b, overlaps_a, last_conflicts); |
b8698a0f | 2630 | |
5b78fc3e JS |
2631 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
2632 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) | |
0ff4040e SP |
2633 | { |
2634 | if (!chrec_contains_symbols (chrec_a) | |
2635 | && !chrec_contains_symbols (chrec_b)) | |
2636 | { | |
b8698a0f L |
2637 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2638 | overlaps_a, overlaps_b, | |
0ff4040e SP |
2639 | last_conflicts); |
2640 | ||
d93817c4 ZD |
2641 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2642 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2643 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2644 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2645 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2646 | dependence_stats.num_siv_independent++; |
2647 | else | |
2648 | dependence_stats.num_siv_dependent++; | |
2649 | } | |
b8698a0f | 2650 | else if (can_use_analyze_subscript_affine_affine (&chrec_a, |
0ff4040e SP |
2651 | &chrec_b)) |
2652 | { | |
b8698a0f L |
2653 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2654 | overlaps_a, overlaps_b, | |
0ff4040e | 2655 | last_conflicts); |
0ff4040e | 2656 | |
d93817c4 ZD |
2657 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2658 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2659 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2660 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2661 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2662 | dependence_stats.num_siv_independent++; |
2663 | else | |
2664 | dependence_stats.num_siv_dependent++; | |
2665 | } | |
2666 | else | |
2667 | goto siv_subscript_dontknow; | |
2668 | } | |
2669 | ||
56cf8686 SP |
2670 | else |
2671 | { | |
0ff4040e SP |
2672 | siv_subscript_dontknow:; |
2673 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2674 | fprintf (dump_file, "siv test failed: unimplemented.\n"); | |
d93817c4 ZD |
2675 | *overlaps_a = conflict_fn_not_known (); |
2676 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2677 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2678 | dependence_stats.num_siv_unimplemented++; |
56cf8686 | 2679 | } |
b8698a0f | 2680 | |
56cf8686 SP |
2681 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2682 | fprintf (dump_file, ")\n"); | |
2683 | } | |
2684 | ||
55a700ac ZD |
2685 | /* Returns false if we can prove that the greatest common divisor of the steps |
2686 | of CHREC does not divide CST, false otherwise. */ | |
56cf8686 SP |
2687 | |
2688 | static bool | |
ed7a4b4b | 2689 | gcd_of_steps_may_divide_p (const_tree chrec, const_tree cst) |
56cf8686 | 2690 | { |
55a700ac ZD |
2691 | HOST_WIDE_INT cd = 0, val; |
2692 | tree step; | |
0ff4040e | 2693 | |
55a700ac ZD |
2694 | if (!host_integerp (cst, 0)) |
2695 | return true; | |
2696 | val = tree_low_cst (cst, 0); | |
2697 | ||
2698 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC) | |
2699 | { | |
2700 | step = CHREC_RIGHT (chrec); | |
2701 | if (!host_integerp (step, 0)) | |
2702 | return true; | |
2703 | cd = gcd (cd, tree_low_cst (step, 0)); | |
2704 | chrec = CHREC_LEFT (chrec); | |
56cf8686 | 2705 | } |
55a700ac ZD |
2706 | |
2707 | return val % cd == 0; | |
56cf8686 SP |
2708 | } |
2709 | ||
da9a21f4 SP |
2710 | /* Analyze a MIV (Multiple Index Variable) subscript with respect to |
2711 | LOOP_NEST. *OVERLAPS_A and *OVERLAPS_B are initialized to the | |
2712 | functions that describe the relation between the elements accessed | |
2713 | twice by CHREC_A and CHREC_B. For k >= 0, the following property | |
2714 | is verified: | |
56cf8686 SP |
2715 | |
2716 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2717 | ||
2718 | static void | |
b8698a0f L |
2719 | analyze_miv_subscript (tree chrec_a, |
2720 | tree chrec_b, | |
2721 | conflict_function **overlaps_a, | |
2722 | conflict_function **overlaps_b, | |
da9a21f4 SP |
2723 | tree *last_conflicts, |
2724 | struct loop *loop_nest) | |
56cf8686 | 2725 | { |
33b30201 SP |
2726 | tree type, difference; |
2727 | ||
0ff4040e | 2728 | dependence_stats.num_miv++; |
56cf8686 SP |
2729 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2730 | fprintf (dump_file, "(analyze_miv_subscript \n"); | |
e2157b49 | 2731 | |
33b30201 | 2732 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
2733 | chrec_a = chrec_convert (type, chrec_a, NULL); |
2734 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 2735 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
b8698a0f | 2736 | |
e2157b49 | 2737 | if (eq_evolutions_p (chrec_a, chrec_b)) |
56cf8686 SP |
2738 | { |
2739 | /* Access functions are the same: all the elements are accessed | |
2740 | in the same order. */ | |
d93817c4 ZD |
2741 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2742 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
4839cb59 ZD |
2743 | *last_conflicts = estimated_loop_iterations_tree |
2744 | (get_chrec_loop (chrec_a), true); | |
0ff4040e | 2745 | dependence_stats.num_miv_dependent++; |
56cf8686 | 2746 | } |
b8698a0f | 2747 | |
56cf8686 SP |
2748 | else if (evolution_function_is_constant_p (difference) |
2749 | /* For the moment, the following is verified: | |
da9a21f4 SP |
2750 | evolution_function_is_affine_multivariate_p (chrec_a, |
2751 | loop_nest->num) */ | |
55a700ac | 2752 | && !gcd_of_steps_may_divide_p (chrec_a, difference)) |
56cf8686 SP |
2753 | { |
2754 | /* testsuite/.../ssa-chrec-33.c | |
b8698a0f L |
2755 | {{21, +, 2}_1, +, -2}_2 vs. {{20, +, 2}_1, +, -2}_2 |
2756 | ||
55a700ac ZD |
2757 | The difference is 1, and all the evolution steps are multiples |
2758 | of 2, consequently there are no overlapping elements. */ | |
d93817c4 ZD |
2759 | *overlaps_a = conflict_fn_no_dependence (); |
2760 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2761 | *last_conflicts = integer_zero_node; |
0ff4040e | 2762 | dependence_stats.num_miv_independent++; |
56cf8686 | 2763 | } |
b8698a0f | 2764 | |
da9a21f4 | 2765 | else if (evolution_function_is_affine_multivariate_p (chrec_a, loop_nest->num) |
0ff4040e | 2766 | && !chrec_contains_symbols (chrec_a) |
da9a21f4 | 2767 | && evolution_function_is_affine_multivariate_p (chrec_b, loop_nest->num) |
0ff4040e | 2768 | && !chrec_contains_symbols (chrec_b)) |
56cf8686 SP |
2769 | { |
2770 | /* testsuite/.../ssa-chrec-35.c | |
2771 | {0, +, 1}_2 vs. {0, +, 1}_3 | |
2772 | the overlapping elements are respectively located at iterations: | |
b8698a0f L |
2773 | {0, +, 1}_x and {0, +, 1}_x, |
2774 | in other words, we have the equality: | |
86df10e3 | 2775 | {0, +, 1}_2 ({0, +, 1}_x) = {0, +, 1}_3 ({0, +, 1}_x) |
b8698a0f L |
2776 | |
2777 | Other examples: | |
2778 | {{0, +, 1}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) = | |
86df10e3 SP |
2779 | {0, +, 1}_1 ({{0, +, 1}_x, +, 2}_y) |
2780 | ||
b8698a0f | 2781 | {{0, +, 2}_1, +, 3}_2 ({0, +, 1}_y, {0, +, 1}_x) = |
86df10e3 | 2782 | {{0, +, 3}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) |
56cf8686 | 2783 | */ |
b8698a0f | 2784 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
86df10e3 | 2785 | overlaps_a, overlaps_b, last_conflicts); |
0ff4040e | 2786 | |
d93817c4 ZD |
2787 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2788 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2789 | dependence_stats.num_miv_unimplemented++; |
d93817c4 ZD |
2790 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2791 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2792 | dependence_stats.num_miv_independent++; |
2793 | else | |
2794 | dependence_stats.num_miv_dependent++; | |
56cf8686 | 2795 | } |
b8698a0f | 2796 | |
56cf8686 SP |
2797 | else |
2798 | { | |
2799 | /* When the analysis is too difficult, answer "don't know". */ | |
0ff4040e SP |
2800 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2801 | fprintf (dump_file, "analyze_miv_subscript test failed: unimplemented.\n"); | |
2802 | ||
d93817c4 ZD |
2803 | *overlaps_a = conflict_fn_not_known (); |
2804 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2805 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2806 | dependence_stats.num_miv_unimplemented++; |
56cf8686 | 2807 | } |
b8698a0f | 2808 | |
56cf8686 SP |
2809 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2810 | fprintf (dump_file, ")\n"); | |
2811 | } | |
2812 | ||
da9a21f4 SP |
2813 | /* Determines the iterations for which CHREC_A is equal to CHREC_B in |
2814 | with respect to LOOP_NEST. OVERLAP_ITERATIONS_A and | |
2815 | OVERLAP_ITERATIONS_B are initialized with two functions that | |
2816 | describe the iterations that contain conflicting elements. | |
b8698a0f | 2817 | |
56cf8686 | 2818 | Remark: For an integer k >= 0, the following equality is true: |
b8698a0f | 2819 | |
56cf8686 SP |
2820 | CHREC_A (OVERLAP_ITERATIONS_A (k)) == CHREC_B (OVERLAP_ITERATIONS_B (k)). |
2821 | */ | |
2822 | ||
b8698a0f L |
2823 | static void |
2824 | analyze_overlapping_iterations (tree chrec_a, | |
2825 | tree chrec_b, | |
2826 | conflict_function **overlap_iterations_a, | |
2827 | conflict_function **overlap_iterations_b, | |
da9a21f4 | 2828 | tree *last_conflicts, struct loop *loop_nest) |
56cf8686 | 2829 | { |
da9a21f4 SP |
2830 | unsigned int lnn = loop_nest->num; |
2831 | ||
0ff4040e | 2832 | dependence_stats.num_subscript_tests++; |
b8698a0f | 2833 | |
56cf8686 SP |
2834 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2835 | { | |
2836 | fprintf (dump_file, "(analyze_overlapping_iterations \n"); | |
2837 | fprintf (dump_file, " (chrec_a = "); | |
2838 | print_generic_expr (dump_file, chrec_a, 0); | |
0ff4040e | 2839 | fprintf (dump_file, ")\n (chrec_b = "); |
56cf8686 SP |
2840 | print_generic_expr (dump_file, chrec_b, 0); |
2841 | fprintf (dump_file, ")\n"); | |
2842 | } | |
0ff4040e | 2843 | |
56cf8686 SP |
2844 | if (chrec_a == NULL_TREE |
2845 | || chrec_b == NULL_TREE | |
2846 | || chrec_contains_undetermined (chrec_a) | |
0ff4040e | 2847 | || chrec_contains_undetermined (chrec_b)) |
56cf8686 | 2848 | { |
0ff4040e | 2849 | dependence_stats.num_subscript_undetermined++; |
b8698a0f | 2850 | |
d93817c4 ZD |
2851 | *overlap_iterations_a = conflict_fn_not_known (); |
2852 | *overlap_iterations_b = conflict_fn_not_known (); | |
56cf8686 | 2853 | } |
0ff4040e | 2854 | |
b8698a0f | 2855 | /* If they are the same chrec, and are affine, they overlap |
0ff4040e SP |
2856 | on every iteration. */ |
2857 | else if (eq_evolutions_p (chrec_a, chrec_b) | |
3e6f8b56 SP |
2858 | && (evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
2859 | || operand_equal_p (chrec_a, chrec_b, 0))) | |
0ff4040e SP |
2860 | { |
2861 | dependence_stats.num_same_subscript_function++; | |
d93817c4 ZD |
2862 | *overlap_iterations_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2863 | *overlap_iterations_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
0ff4040e SP |
2864 | *last_conflicts = chrec_dont_know; |
2865 | } | |
2866 | ||
2867 | /* If they aren't the same, and aren't affine, we can't do anything | |
3e6f8b56 | 2868 | yet. */ |
b8698a0f | 2869 | else if ((chrec_contains_symbols (chrec_a) |
0ff4040e | 2870 | || chrec_contains_symbols (chrec_b)) |
da9a21f4 SP |
2871 | && (!evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
2872 | || !evolution_function_is_affine_multivariate_p (chrec_b, lnn))) | |
0ff4040e SP |
2873 | { |
2874 | dependence_stats.num_subscript_undetermined++; | |
d93817c4 ZD |
2875 | *overlap_iterations_a = conflict_fn_not_known (); |
2876 | *overlap_iterations_b = conflict_fn_not_known (); | |
0ff4040e SP |
2877 | } |
2878 | ||
56cf8686 | 2879 | else if (ziv_subscript_p (chrec_a, chrec_b)) |
b8698a0f | 2880 | analyze_ziv_subscript (chrec_a, chrec_b, |
86df10e3 SP |
2881 | overlap_iterations_a, overlap_iterations_b, |
2882 | last_conflicts); | |
b8698a0f | 2883 | |
56cf8686 | 2884 | else if (siv_subscript_p (chrec_a, chrec_b)) |
b8698a0f L |
2885 | analyze_siv_subscript (chrec_a, chrec_b, |
2886 | overlap_iterations_a, overlap_iterations_b, | |
5b78fc3e | 2887 | last_conflicts, lnn); |
b8698a0f | 2888 | |
56cf8686 | 2889 | else |
b8698a0f | 2890 | analyze_miv_subscript (chrec_a, chrec_b, |
86df10e3 | 2891 | overlap_iterations_a, overlap_iterations_b, |
da9a21f4 | 2892 | last_conflicts, loop_nest); |
b8698a0f | 2893 | |
56cf8686 SP |
2894 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2895 | { | |
2896 | fprintf (dump_file, " (overlap_iterations_a = "); | |
d93817c4 | 2897 | dump_conflict_function (dump_file, *overlap_iterations_a); |
56cf8686 | 2898 | fprintf (dump_file, ")\n (overlap_iterations_b = "); |
d93817c4 | 2899 | dump_conflict_function (dump_file, *overlap_iterations_b); |
56cf8686 | 2900 | fprintf (dump_file, ")\n"); |
0ff4040e | 2901 | fprintf (dump_file, ")\n"); |
56cf8686 SP |
2902 | } |
2903 | } | |
2904 | ||
ba42e045 | 2905 | /* Helper function for uniquely inserting distance vectors. */ |
56cf8686 | 2906 | |
ba42e045 SP |
2907 | static void |
2908 | save_dist_v (struct data_dependence_relation *ddr, lambda_vector dist_v) | |
2909 | { | |
2910 | unsigned i; | |
2911 | lambda_vector v; | |
56cf8686 | 2912 | |
ac47786e | 2913 | FOR_EACH_VEC_ELT (lambda_vector, DDR_DIST_VECTS (ddr), i, v) |
ba42e045 SP |
2914 | if (lambda_vector_equal (v, dist_v, DDR_NB_LOOPS (ddr))) |
2915 | return; | |
56cf8686 | 2916 | |
ba42e045 SP |
2917 | VEC_safe_push (lambda_vector, heap, DDR_DIST_VECTS (ddr), dist_v); |
2918 | } | |
56cf8686 | 2919 | |
ba42e045 SP |
2920 | /* Helper function for uniquely inserting direction vectors. */ |
2921 | ||
2922 | static void | |
2923 | save_dir_v (struct data_dependence_relation *ddr, lambda_vector dir_v) | |
56cf8686 SP |
2924 | { |
2925 | unsigned i; | |
ba42e045 | 2926 | lambda_vector v; |
0ff4040e | 2927 | |
ac47786e | 2928 | FOR_EACH_VEC_ELT (lambda_vector, DDR_DIR_VECTS (ddr), i, v) |
ba42e045 SP |
2929 | if (lambda_vector_equal (v, dir_v, DDR_NB_LOOPS (ddr))) |
2930 | return; | |
2931 | ||
2932 | VEC_safe_push (lambda_vector, heap, DDR_DIR_VECTS (ddr), dir_v); | |
2933 | } | |
2934 | ||
2935 | /* Add a distance of 1 on all the loops outer than INDEX. If we | |
2936 | haven't yet determined a distance for this outer loop, push a new | |
2937 | distance vector composed of the previous distance, and a distance | |
2938 | of 1 for this outer loop. Example: | |
2939 | ||
2940 | | loop_1 | |
2941 | | loop_2 | |
2942 | | A[10] | |
2943 | | endloop_2 | |
2944 | | endloop_1 | |
2945 | ||
2946 | Saved vectors are of the form (dist_in_1, dist_in_2). First, we | |
2947 | save (0, 1), then we have to save (1, 0). */ | |
2948 | ||
2949 | static void | |
2950 | add_outer_distances (struct data_dependence_relation *ddr, | |
2951 | lambda_vector dist_v, int index) | |
2952 | { | |
2953 | /* For each outer loop where init_v is not set, the accesses are | |
2954 | in dependence of distance 1 in the loop. */ | |
2955 | while (--index >= 0) | |
2956 | { | |
2957 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
2958 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
2959 | save_v[index] = 1; | |
2960 | save_dist_v (ddr, save_v); | |
2961 | } | |
2962 | } | |
2963 | ||
2964 | /* Return false when fail to represent the data dependence as a | |
2965 | distance vector. INIT_B is set to true when a component has been | |
2966 | added to the distance vector DIST_V. INDEX_CARRY is then set to | |
2967 | the index in DIST_V that carries the dependence. */ | |
2968 | ||
2969 | static bool | |
2970 | build_classic_dist_vector_1 (struct data_dependence_relation *ddr, | |
2971 | struct data_reference *ddr_a, | |
2972 | struct data_reference *ddr_b, | |
2973 | lambda_vector dist_v, bool *init_b, | |
2974 | int *index_carry) | |
2975 | { | |
2976 | unsigned i; | |
2977 | lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
0ff4040e | 2978 | |
36d59cf7 | 2979 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
56cf8686 | 2980 | { |
86df10e3 | 2981 | tree access_fn_a, access_fn_b; |
36d59cf7 | 2982 | struct subscript *subscript = DDR_SUBSCRIPT (ddr, i); |
56cf8686 SP |
2983 | |
2984 | if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
2985 | { |
2986 | non_affine_dependence_relation (ddr); | |
ba42e045 | 2987 | return false; |
86df10e3 SP |
2988 | } |
2989 | ||
ba42e045 SP |
2990 | access_fn_a = DR_ACCESS_FN (ddr_a, i); |
2991 | access_fn_b = DR_ACCESS_FN (ddr_b, i); | |
56cf8686 | 2992 | |
b8698a0f | 2993 | if (TREE_CODE (access_fn_a) == POLYNOMIAL_CHREC |
86df10e3 | 2994 | && TREE_CODE (access_fn_b) == POLYNOMIAL_CHREC) |
56cf8686 | 2995 | { |
ba42e045 | 2996 | int dist, index; |
a130584a SP |
2997 | int var_a = CHREC_VARIABLE (access_fn_a); |
2998 | int var_b = CHREC_VARIABLE (access_fn_b); | |
ba42e045 | 2999 | |
a130584a SP |
3000 | if (var_a != var_b |
3001 | || chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
3002 | { |
3003 | non_affine_dependence_relation (ddr); | |
ba42e045 | 3004 | return false; |
86df10e3 | 3005 | } |
b8698a0f | 3006 | |
6b6fa4e9 | 3007 | dist = int_cst_value (SUB_DISTANCE (subscript)); |
a130584a SP |
3008 | index = index_in_loop_nest (var_a, DDR_LOOP_NEST (ddr)); |
3009 | *index_carry = MIN (index, *index_carry); | |
56cf8686 | 3010 | |
ba42e045 SP |
3011 | /* This is the subscript coupling test. If we have already |
3012 | recorded a distance for this loop (a distance coming from | |
3013 | another subscript), it should be the same. For example, | |
3014 | in the following code, there is no dependence: | |
3015 | ||
56cf8686 SP |
3016 | | loop i = 0, N, 1 |
3017 | | T[i+1][i] = ... | |
3018 | | ... = T[i][i] | |
3019 | | endloop | |
ba42e045 SP |
3020 | */ |
3021 | if (init_v[index] != 0 && dist_v[index] != dist) | |
56cf8686 | 3022 | { |
36d59cf7 | 3023 | finalize_ddr_dependent (ddr, chrec_known); |
ba42e045 | 3024 | return false; |
56cf8686 SP |
3025 | } |
3026 | ||
ba42e045 SP |
3027 | dist_v[index] = dist; |
3028 | init_v[index] = 1; | |
3029 | *init_b = true; | |
3030 | } | |
a50411de | 3031 | else if (!operand_equal_p (access_fn_a, access_fn_b, 0)) |
ba42e045 SP |
3032 | { |
3033 | /* This can be for example an affine vs. constant dependence | |
3034 | (T[i] vs. T[3]) that is not an affine dependence and is | |
3035 | not representable as a distance vector. */ | |
3036 | non_affine_dependence_relation (ddr); | |
3037 | return false; | |
56cf8686 SP |
3038 | } |
3039 | } | |
304afda6 | 3040 | |
ba42e045 SP |
3041 | return true; |
3042 | } | |
304afda6 | 3043 | |
1baf2906 SP |
3044 | /* Return true when the DDR contains only constant access functions. */ |
3045 | ||
3046 | static bool | |
ed7a4b4b | 3047 | constant_access_functions (const struct data_dependence_relation *ddr) |
1baf2906 SP |
3048 | { |
3049 | unsigned i; | |
3050 | ||
3051 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3052 | if (!evolution_function_is_constant_p (DR_ACCESS_FN (DDR_A (ddr), i)) | |
3053 | || !evolution_function_is_constant_p (DR_ACCESS_FN (DDR_B (ddr), i))) | |
3054 | return false; | |
3055 | ||
3056 | return true; | |
3057 | } | |
3058 | ||
ba42e045 | 3059 | /* Helper function for the case where DDR_A and DDR_B are the same |
097392de SP |
3060 | multivariate access function with a constant step. For an example |
3061 | see pr34635-1.c. */ | |
86df10e3 | 3062 | |
ba42e045 SP |
3063 | static void |
3064 | add_multivariate_self_dist (struct data_dependence_relation *ddr, tree c_2) | |
3065 | { | |
3066 | int x_1, x_2; | |
3067 | tree c_1 = CHREC_LEFT (c_2); | |
3068 | tree c_0 = CHREC_LEFT (c_1); | |
3069 | lambda_vector dist_v; | |
0ca2faee | 3070 | int v1, v2, cd; |
86df10e3 | 3071 | |
b1e75954 SP |
3072 | /* Polynomials with more than 2 variables are not handled yet. When |
3073 | the evolution steps are parameters, it is not possible to | |
3074 | represent the dependence using classical distance vectors. */ | |
3075 | if (TREE_CODE (c_0) != INTEGER_CST | |
3076 | || TREE_CODE (CHREC_RIGHT (c_1)) != INTEGER_CST | |
3077 | || TREE_CODE (CHREC_RIGHT (c_2)) != INTEGER_CST) | |
3078 | { | |
3079 | DDR_AFFINE_P (ddr) = false; | |
ba42e045 SP |
3080 | return; |
3081 | } | |
304afda6 | 3082 | |
ba42e045 SP |
3083 | x_2 = index_in_loop_nest (CHREC_VARIABLE (c_2), DDR_LOOP_NEST (ddr)); |
3084 | x_1 = index_in_loop_nest (CHREC_VARIABLE (c_1), DDR_LOOP_NEST (ddr)); | |
304afda6 | 3085 | |
ba42e045 SP |
3086 | /* For "{{0, +, 2}_1, +, 3}_2" the distance vector is (3, -2). */ |
3087 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
6b6fa4e9 SP |
3088 | v1 = int_cst_value (CHREC_RIGHT (c_1)); |
3089 | v2 = int_cst_value (CHREC_RIGHT (c_2)); | |
0ca2faee ZD |
3090 | cd = gcd (v1, v2); |
3091 | v1 /= cd; | |
3092 | v2 /= cd; | |
3093 | ||
3094 | if (v2 < 0) | |
3095 | { | |
3096 | v2 = -v2; | |
3097 | v1 = -v1; | |
3098 | } | |
3099 | ||
3100 | dist_v[x_1] = v2; | |
3101 | dist_v[x_2] = -v1; | |
ba42e045 | 3102 | save_dist_v (ddr, dist_v); |
304afda6 | 3103 | |
ba42e045 SP |
3104 | add_outer_distances (ddr, dist_v, x_1); |
3105 | } | |
304afda6 | 3106 | |
ba42e045 SP |
3107 | /* Helper function for the case where DDR_A and DDR_B are the same |
3108 | access functions. */ | |
37b8a73b | 3109 | |
ba42e045 SP |
3110 | static void |
3111 | add_other_self_distances (struct data_dependence_relation *ddr) | |
3112 | { | |
3113 | lambda_vector dist_v; | |
3114 | unsigned i; | |
3115 | int index_carry = DDR_NB_LOOPS (ddr); | |
304afda6 | 3116 | |
ba42e045 | 3117 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
37b8a73b | 3118 | { |
ba42e045 | 3119 | tree access_fun = DR_ACCESS_FN (DDR_A (ddr), i); |
304afda6 | 3120 | |
ba42e045 | 3121 | if (TREE_CODE (access_fun) == POLYNOMIAL_CHREC) |
304afda6 | 3122 | { |
ba42e045 SP |
3123 | if (!evolution_function_is_univariate_p (access_fun)) |
3124 | { | |
3125 | if (DDR_NUM_SUBSCRIPTS (ddr) != 1) | |
3126 | { | |
3127 | DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; | |
3128 | return; | |
3129 | } | |
3130 | ||
097392de SP |
3131 | access_fun = DR_ACCESS_FN (DDR_A (ddr), 0); |
3132 | ||
3133 | if (TREE_CODE (CHREC_LEFT (access_fun)) == POLYNOMIAL_CHREC) | |
3134 | add_multivariate_self_dist (ddr, access_fun); | |
3135 | else | |
3136 | /* The evolution step is not constant: it varies in | |
3137 | the outer loop, so this cannot be represented by a | |
3138 | distance vector. For example in pr34635.c the | |
3139 | evolution is {0, +, {0, +, 4}_1}_2. */ | |
3140 | DDR_AFFINE_P (ddr) = false; | |
3141 | ||
ba42e045 SP |
3142 | return; |
3143 | } | |
3144 | ||
3145 | index_carry = MIN (index_carry, | |
3146 | index_in_loop_nest (CHREC_VARIABLE (access_fun), | |
3147 | DDR_LOOP_NEST (ddr))); | |
304afda6 | 3148 | } |
37b8a73b SP |
3149 | } |
3150 | ||
ba42e045 SP |
3151 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3152 | add_outer_distances (ddr, dist_v, index_carry); | |
56cf8686 SP |
3153 | } |
3154 | ||
1baf2906 SP |
3155 | static void |
3156 | insert_innermost_unit_dist_vector (struct data_dependence_relation *ddr) | |
3157 | { | |
3158 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3159 | ||
3160 | dist_v[DDR_INNER_LOOP (ddr)] = 1; | |
3161 | save_dist_v (ddr, dist_v); | |
3162 | } | |
3163 | ||
3164 | /* Adds a unit distance vector to DDR when there is a 0 overlap. This | |
3165 | is the case for example when access functions are the same and | |
3166 | equal to a constant, as in: | |
3167 | ||
3168 | | loop_1 | |
3169 | | A[3] = ... | |
3170 | | ... = A[3] | |
3171 | | endloop_1 | |
3172 | ||
3173 | in which case the distance vectors are (0) and (1). */ | |
3174 | ||
3175 | static void | |
3176 | add_distance_for_zero_overlaps (struct data_dependence_relation *ddr) | |
3177 | { | |
3178 | unsigned i, j; | |
3179 | ||
3180 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3181 | { | |
3182 | subscript_p sub = DDR_SUBSCRIPT (ddr, i); | |
3183 | conflict_function *ca = SUB_CONFLICTS_IN_A (sub); | |
3184 | conflict_function *cb = SUB_CONFLICTS_IN_B (sub); | |
3185 | ||
3186 | for (j = 0; j < ca->n; j++) | |
3187 | if (affine_function_zero_p (ca->fns[j])) | |
3188 | { | |
3189 | insert_innermost_unit_dist_vector (ddr); | |
3190 | return; | |
3191 | } | |
3192 | ||
3193 | for (j = 0; j < cb->n; j++) | |
3194 | if (affine_function_zero_p (cb->fns[j])) | |
3195 | { | |
3196 | insert_innermost_unit_dist_vector (ddr); | |
3197 | return; | |
3198 | } | |
3199 | } | |
3200 | } | |
3201 | ||
ba42e045 SP |
3202 | /* Compute the classic per loop distance vector. DDR is the data |
3203 | dependence relation to build a vector from. Return false when fail | |
3204 | to represent the data dependence as a distance vector. */ | |
56cf8686 | 3205 | |
464f49d8 | 3206 | static bool |
da9a21f4 SP |
3207 | build_classic_dist_vector (struct data_dependence_relation *ddr, |
3208 | struct loop *loop_nest) | |
56cf8686 | 3209 | { |
304afda6 | 3210 | bool init_b = false; |
ba42e045 SP |
3211 | int index_carry = DDR_NB_LOOPS (ddr); |
3212 | lambda_vector dist_v; | |
304afda6 | 3213 | |
36d59cf7 | 3214 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
2f470326 | 3215 | return false; |
ba42e045 SP |
3216 | |
3217 | if (same_access_functions (ddr)) | |
56cf8686 | 3218 | { |
ba42e045 SP |
3219 | /* Save the 0 vector. */ |
3220 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3221 | save_dist_v (ddr, dist_v); | |
56cf8686 | 3222 | |
1baf2906 SP |
3223 | if (constant_access_functions (ddr)) |
3224 | add_distance_for_zero_overlaps (ddr); | |
3225 | ||
ba42e045 SP |
3226 | if (DDR_NB_LOOPS (ddr) > 1) |
3227 | add_other_self_distances (ddr); | |
86df10e3 | 3228 | |
ba42e045 SP |
3229 | return true; |
3230 | } | |
86df10e3 | 3231 | |
ba42e045 SP |
3232 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3233 | if (!build_classic_dist_vector_1 (ddr, DDR_A (ddr), DDR_B (ddr), | |
3234 | dist_v, &init_b, &index_carry)) | |
3235 | return false; | |
86df10e3 | 3236 | |
ba42e045 SP |
3237 | /* Save the distance vector if we initialized one. */ |
3238 | if (init_b) | |
3239 | { | |
3240 | /* Verify a basic constraint: classic distance vectors should | |
3241 | always be lexicographically positive. | |
3242 | ||
3243 | Data references are collected in the order of execution of | |
3244 | the program, thus for the following loop | |
3245 | ||
3246 | | for (i = 1; i < 100; i++) | |
3247 | | for (j = 1; j < 100; j++) | |
3248 | | { | |
3249 | | t = T[j+1][i-1]; // A | |
3250 | | T[j][i] = t + 2; // B | |
3251 | | } | |
3252 | ||
3253 | references are collected following the direction of the wind: | |
3254 | A then B. The data dependence tests are performed also | |
3255 | following this order, such that we're looking at the distance | |
3256 | separating the elements accessed by A from the elements later | |
3257 | accessed by B. But in this example, the distance returned by | |
3258 | test_dep (A, B) is lexicographically negative (-1, 1), that | |
3259 | means that the access A occurs later than B with respect to | |
3260 | the outer loop, ie. we're actually looking upwind. In this | |
3261 | case we solve test_dep (B, A) looking downwind to the | |
3262 | lexicographically positive solution, that returns the | |
3263 | distance vector (1, -1). */ | |
3264 | if (!lambda_vector_lexico_pos (dist_v, DDR_NB_LOOPS (ddr))) | |
3265 | { | |
3266 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
2f470326 JJ |
3267 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3268 | loop_nest)) | |
3269 | return false; | |
ba42e045 | 3270 | compute_subscript_distance (ddr); |
2f470326 JJ |
3271 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3272 | save_v, &init_b, &index_carry)) | |
3273 | return false; | |
ba42e045 | 3274 | save_dist_v (ddr, save_v); |
71d5b5e1 | 3275 | DDR_REVERSED_P (ddr) = true; |
ba42e045 SP |
3276 | |
3277 | /* In this case there is a dependence forward for all the | |
3278 | outer loops: | |
3279 | ||
3280 | | for (k = 1; k < 100; k++) | |
3281 | | for (i = 1; i < 100; i++) | |
3282 | | for (j = 1; j < 100; j++) | |
3283 | | { | |
3284 | | t = T[j+1][i-1]; // A | |
3285 | | T[j][i] = t + 2; // B | |
3286 | | } | |
3287 | ||
b8698a0f | 3288 | the vectors are: |
ba42e045 SP |
3289 | (0, 1, -1) |
3290 | (1, 1, -1) | |
3291 | (1, -1, 1) | |
3292 | */ | |
3293 | if (DDR_NB_LOOPS (ddr) > 1) | |
3294 | { | |
3295 | add_outer_distances (ddr, save_v, index_carry); | |
3296 | add_outer_distances (ddr, dist_v, index_carry); | |
86df10e3 | 3297 | } |
ba42e045 SP |
3298 | } |
3299 | else | |
3300 | { | |
3301 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3302 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3303 | |
ba42e045 | 3304 | if (DDR_NB_LOOPS (ddr) > 1) |
56cf8686 | 3305 | { |
ba42e045 | 3306 | lambda_vector opposite_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
86df10e3 | 3307 | |
2f470326 JJ |
3308 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), |
3309 | DDR_A (ddr), loop_nest)) | |
3310 | return false; | |
ba42e045 | 3311 | compute_subscript_distance (ddr); |
2f470326 JJ |
3312 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3313 | opposite_v, &init_b, | |
3314 | &index_carry)) | |
3315 | return false; | |
86df10e3 | 3316 | |
2f470326 | 3317 | save_dist_v (ddr, save_v); |
ba42e045 SP |
3318 | add_outer_distances (ddr, dist_v, index_carry); |
3319 | add_outer_distances (ddr, opposite_v, index_carry); | |
56cf8686 | 3320 | } |
2f470326 JJ |
3321 | else |
3322 | save_dist_v (ddr, save_v); | |
56cf8686 SP |
3323 | } |
3324 | } | |
ba42e045 SP |
3325 | else |
3326 | { | |
3327 | /* There is a distance of 1 on all the outer loops: Example: | |
3328 | there is a dependence of distance 1 on loop_1 for the array A. | |
304afda6 | 3329 | |
ba42e045 SP |
3330 | | loop_1 |
3331 | | A[5] = ... | |
3332 | | endloop | |
3333 | */ | |
3334 | add_outer_distances (ddr, dist_v, | |
3335 | lambda_vector_first_nz (dist_v, | |
3336 | DDR_NB_LOOPS (ddr), 0)); | |
3337 | } | |
3338 | ||
3339 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
304afda6 | 3340 | { |
ba42e045 | 3341 | unsigned i; |
304afda6 | 3342 | |
ba42e045 SP |
3343 | fprintf (dump_file, "(build_classic_dist_vector\n"); |
3344 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3345 | { | |
3346 | fprintf (dump_file, " dist_vector = ("); | |
3347 | print_lambda_vector (dump_file, DDR_DIST_VECT (ddr, i), | |
3348 | DDR_NB_LOOPS (ddr)); | |
3349 | fprintf (dump_file, " )\n"); | |
3350 | } | |
3351 | fprintf (dump_file, ")\n"); | |
304afda6 SP |
3352 | } |
3353 | ||
ba42e045 SP |
3354 | return true; |
3355 | } | |
56cf8686 | 3356 | |
ba42e045 SP |
3357 | /* Return the direction for a given distance. |
3358 | FIXME: Computing dir this way is suboptimal, since dir can catch | |
3359 | cases that dist is unable to represent. */ | |
86df10e3 | 3360 | |
ba42e045 SP |
3361 | static inline enum data_dependence_direction |
3362 | dir_from_dist (int dist) | |
3363 | { | |
3364 | if (dist > 0) | |
3365 | return dir_positive; | |
3366 | else if (dist < 0) | |
3367 | return dir_negative; | |
3368 | else | |
3369 | return dir_equal; | |
3370 | } | |
304afda6 | 3371 | |
ba42e045 SP |
3372 | /* Compute the classic per loop direction vector. DDR is the data |
3373 | dependence relation to build a vector from. */ | |
304afda6 | 3374 | |
ba42e045 SP |
3375 | static void |
3376 | build_classic_dir_vector (struct data_dependence_relation *ddr) | |
3377 | { | |
3378 | unsigned i, j; | |
3379 | lambda_vector dist_v; | |
86df10e3 | 3380 | |
ac47786e | 3381 | FOR_EACH_VEC_ELT (lambda_vector, DDR_DIST_VECTS (ddr), i, dist_v) |
ba42e045 SP |
3382 | { |
3383 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3384 | |
ba42e045 SP |
3385 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) |
3386 | dir_v[j] = dir_from_dist (dist_v[j]); | |
304afda6 | 3387 | |
ba42e045 SP |
3388 | save_dir_v (ddr, dir_v); |
3389 | } | |
56cf8686 SP |
3390 | } |
3391 | ||
ba42e045 SP |
3392 | /* Helper function. Returns true when there is a dependence between |
3393 | data references DRA and DRB. */ | |
0ff4040e | 3394 | |
ba42e045 SP |
3395 | static bool |
3396 | subscript_dependence_tester_1 (struct data_dependence_relation *ddr, | |
3397 | struct data_reference *dra, | |
da9a21f4 SP |
3398 | struct data_reference *drb, |
3399 | struct loop *loop_nest) | |
0ff4040e SP |
3400 | { |
3401 | unsigned int i; | |
0ff4040e | 3402 | tree last_conflicts; |
ebf78a47 | 3403 | struct subscript *subscript; |
ba42e045 | 3404 | |
ebf78a47 SP |
3405 | for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript); |
3406 | i++) | |
0ff4040e | 3407 | { |
d93817c4 | 3408 | conflict_function *overlaps_a, *overlaps_b; |
ebf78a47 | 3409 | |
b8698a0f | 3410 | analyze_overlapping_iterations (DR_ACCESS_FN (dra, i), |
0ff4040e | 3411 | DR_ACCESS_FN (drb, i), |
b8698a0f | 3412 | &overlaps_a, &overlaps_b, |
da9a21f4 | 3413 | &last_conflicts, loop_nest); |
ebf78a47 | 3414 | |
d93817c4 ZD |
3415 | if (CF_NOT_KNOWN_P (overlaps_a) |
3416 | || CF_NOT_KNOWN_P (overlaps_b)) | |
0ff4040e SP |
3417 | { |
3418 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
3419 | dependence_stats.num_dependence_undetermined++; | |
d93817c4 ZD |
3420 | free_conflict_function (overlaps_a); |
3421 | free_conflict_function (overlaps_b); | |
ba42e045 | 3422 | return false; |
0ff4040e | 3423 | } |
ebf78a47 | 3424 | |
d93817c4 ZD |
3425 | else if (CF_NO_DEPENDENCE_P (overlaps_a) |
3426 | || CF_NO_DEPENDENCE_P (overlaps_b)) | |
0ff4040e SP |
3427 | { |
3428 | finalize_ddr_dependent (ddr, chrec_known); | |
3429 | dependence_stats.num_dependence_independent++; | |
d93817c4 ZD |
3430 | free_conflict_function (overlaps_a); |
3431 | free_conflict_function (overlaps_b); | |
ba42e045 | 3432 | return false; |
0ff4040e | 3433 | } |
ebf78a47 | 3434 | |
0ff4040e SP |
3435 | else |
3436 | { | |
6935bae7 SP |
3437 | if (SUB_CONFLICTS_IN_A (subscript)) |
3438 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
3439 | if (SUB_CONFLICTS_IN_B (subscript)) | |
3440 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
3441 | ||
0ff4040e SP |
3442 | SUB_CONFLICTS_IN_A (subscript) = overlaps_a; |
3443 | SUB_CONFLICTS_IN_B (subscript) = overlaps_b; | |
3444 | SUB_LAST_CONFLICT (subscript) = last_conflicts; | |
3445 | } | |
3446 | } | |
3447 | ||
ba42e045 SP |
3448 | return true; |
3449 | } | |
3450 | ||
da9a21f4 | 3451 | /* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */ |
ba42e045 SP |
3452 | |
3453 | static void | |
da9a21f4 SP |
3454 | subscript_dependence_tester (struct data_dependence_relation *ddr, |
3455 | struct loop *loop_nest) | |
ba42e045 | 3456 | { |
b8698a0f | 3457 | |
ba42e045 SP |
3458 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3459 | fprintf (dump_file, "(subscript_dependence_tester \n"); | |
b8698a0f | 3460 | |
da9a21f4 | 3461 | if (subscript_dependence_tester_1 (ddr, DDR_A (ddr), DDR_B (ddr), loop_nest)) |
ba42e045 | 3462 | dependence_stats.num_dependence_dependent++; |
0ff4040e | 3463 | |
0ff4040e | 3464 | compute_subscript_distance (ddr); |
da9a21f4 | 3465 | if (build_classic_dist_vector (ddr, loop_nest)) |
ba42e045 | 3466 | build_classic_dir_vector (ddr); |
0ff4040e SP |
3467 | |
3468 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3469 | fprintf (dump_file, ")\n"); | |
3470 | } | |
3471 | ||
56cf8686 | 3472 | /* Returns true when all the access functions of A are affine or |
da9a21f4 | 3473 | constant with respect to LOOP_NEST. */ |
56cf8686 | 3474 | |
b8698a0f | 3475 | static bool |
ed7a4b4b KG |
3476 | access_functions_are_affine_or_constant_p (const struct data_reference *a, |
3477 | const struct loop *loop_nest) | |
56cf8686 SP |
3478 | { |
3479 | unsigned int i; | |
3d8864c0 | 3480 | VEC(tree,heap) *fns = DR_ACCESS_FNS (a); |
9cbb7989 | 3481 | tree t; |
3d8864c0 | 3482 | |
ac47786e | 3483 | FOR_EACH_VEC_ELT (tree, fns, i, t) |
da9a21f4 SP |
3484 | if (!evolution_function_is_invariant_p (t, loop_nest->num) |
3485 | && !evolution_function_is_affine_multivariate_p (t, loop_nest->num)) | |
56cf8686 | 3486 | return false; |
b8698a0f | 3487 | |
56cf8686 SP |
3488 | return true; |
3489 | } | |
3490 | ||
3d8864c0 SP |
3491 | /* Initializes an equation for an OMEGA problem using the information |
3492 | contained in the ACCESS_FUN. Returns true when the operation | |
3493 | succeeded. | |
3494 | ||
3495 | PB is the omega constraint system. | |
3496 | EQ is the number of the equation to be initialized. | |
3497 | OFFSET is used for shifting the variables names in the constraints: | |
3498 | a constrain is composed of 2 * the number of variables surrounding | |
3499 | dependence accesses. OFFSET is set either to 0 for the first n variables, | |
3500 | then it is set to n. | |
3501 | ACCESS_FUN is expected to be an affine chrec. */ | |
3502 | ||
3503 | static bool | |
b8698a0f L |
3504 | init_omega_eq_with_af (omega_pb pb, unsigned eq, |
3505 | unsigned int offset, tree access_fun, | |
3d8864c0 SP |
3506 | struct data_dependence_relation *ddr) |
3507 | { | |
3508 | switch (TREE_CODE (access_fun)) | |
3509 | { | |
3510 | case POLYNOMIAL_CHREC: | |
3511 | { | |
3512 | tree left = CHREC_LEFT (access_fun); | |
3513 | tree right = CHREC_RIGHT (access_fun); | |
3514 | int var = CHREC_VARIABLE (access_fun); | |
3515 | unsigned var_idx; | |
3516 | ||
3517 | if (TREE_CODE (right) != INTEGER_CST) | |
3518 | return false; | |
3519 | ||
3520 | var_idx = index_in_loop_nest (var, DDR_LOOP_NEST (ddr)); | |
6b6fa4e9 | 3521 | pb->eqs[eq].coef[offset + var_idx + 1] = int_cst_value (right); |
3d8864c0 SP |
3522 | |
3523 | /* Compute the innermost loop index. */ | |
3524 | DDR_INNER_LOOP (ddr) = MAX (DDR_INNER_LOOP (ddr), var_idx); | |
3525 | ||
3526 | if (offset == 0) | |
b8698a0f | 3527 | pb->eqs[eq].coef[var_idx + DDR_NB_LOOPS (ddr) + 1] |
6b6fa4e9 | 3528 | += int_cst_value (right); |
3d8864c0 SP |
3529 | |
3530 | switch (TREE_CODE (left)) | |
3531 | { | |
3532 | case POLYNOMIAL_CHREC: | |
3533 | return init_omega_eq_with_af (pb, eq, offset, left, ddr); | |
3534 | ||
3535 | case INTEGER_CST: | |
6b6fa4e9 | 3536 | pb->eqs[eq].coef[0] += int_cst_value (left); |
3d8864c0 SP |
3537 | return true; |
3538 | ||
3539 | default: | |
3540 | return false; | |
3541 | } | |
3542 | } | |
3543 | ||
3544 | case INTEGER_CST: | |
6b6fa4e9 | 3545 | pb->eqs[eq].coef[0] += int_cst_value (access_fun); |
3d8864c0 SP |
3546 | return true; |
3547 | ||
3548 | default: | |
3549 | return false; | |
3550 | } | |
3551 | } | |
3552 | ||
3553 | /* As explained in the comments preceding init_omega_for_ddr, we have | |
3554 | to set up a system for each loop level, setting outer loops | |
3555 | variation to zero, and current loop variation to positive or zero. | |
3556 | Save each lexico positive distance vector. */ | |
3557 | ||
3558 | static void | |
3559 | omega_extract_distance_vectors (omega_pb pb, | |
3560 | struct data_dependence_relation *ddr) | |
3561 | { | |
3562 | int eq, geq; | |
3563 | unsigned i, j; | |
3564 | struct loop *loopi, *loopj; | |
3565 | enum omega_result res; | |
3566 | ||
3567 | /* Set a new problem for each loop in the nest. The basis is the | |
3568 | problem that we have initialized until now. On top of this we | |
3569 | add new constraints. */ | |
b8698a0f | 3570 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
3d8864c0 SP |
3571 | && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++) |
3572 | { | |
3573 | int dist = 0; | |
3574 | omega_pb copy = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), | |
3575 | DDR_NB_LOOPS (ddr)); | |
3576 | ||
3577 | omega_copy_problem (copy, pb); | |
3578 | ||
3579 | /* For all the outer loops "loop_j", add "dj = 0". */ | |
3580 | for (j = 0; | |
3581 | j < i && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), j, loopj); j++) | |
3582 | { | |
3583 | eq = omega_add_zero_eq (copy, omega_black); | |
3584 | copy->eqs[eq].coef[j + 1] = 1; | |
3585 | } | |
3586 | ||
3587 | /* For "loop_i", add "0 <= di". */ | |
3588 | geq = omega_add_zero_geq (copy, omega_black); | |
3589 | copy->geqs[geq].coef[i + 1] = 1; | |
3590 | ||
3591 | /* Reduce the constraint system, and test that the current | |
3592 | problem is feasible. */ | |
3593 | res = omega_simplify_problem (copy); | |
b8698a0f | 3594 | if (res == omega_false |
3d8864c0 SP |
3595 | || res == omega_unknown |
3596 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3597 | goto next_problem; | |
3598 | ||
3599 | for (eq = 0; eq < copy->num_subs; eq++) | |
3600 | if (copy->subs[eq].key == (int) i + 1) | |
3601 | { | |
3602 | dist = copy->subs[eq].coef[0]; | |
3603 | goto found_dist; | |
3604 | } | |
3605 | ||
3606 | if (dist == 0) | |
3607 | { | |
3608 | /* Reinitialize problem... */ | |
3609 | omega_copy_problem (copy, pb); | |
3610 | for (j = 0; | |
3611 | j < i && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), j, loopj); j++) | |
3612 | { | |
3613 | eq = omega_add_zero_eq (copy, omega_black); | |
3614 | copy->eqs[eq].coef[j + 1] = 1; | |
3615 | } | |
3616 | ||
3617 | /* ..., but this time "di = 1". */ | |
3618 | eq = omega_add_zero_eq (copy, omega_black); | |
3619 | copy->eqs[eq].coef[i + 1] = 1; | |
3620 | copy->eqs[eq].coef[0] = -1; | |
3621 | ||
3622 | res = omega_simplify_problem (copy); | |
b8698a0f | 3623 | if (res == omega_false |
3d8864c0 SP |
3624 | || res == omega_unknown |
3625 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3626 | goto next_problem; | |
3627 | ||
3628 | for (eq = 0; eq < copy->num_subs; eq++) | |
3629 | if (copy->subs[eq].key == (int) i + 1) | |
3630 | { | |
3631 | dist = copy->subs[eq].coef[0]; | |
3632 | goto found_dist; | |
3633 | } | |
3634 | } | |
3635 | ||
3636 | found_dist:; | |
3637 | /* Save the lexicographically positive distance vector. */ | |
3638 | if (dist >= 0) | |
3639 | { | |
3640 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3641 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3642 | ||
3643 | dist_v[i] = dist; | |
3644 | ||
3645 | for (eq = 0; eq < copy->num_subs; eq++) | |
3646 | if (copy->subs[eq].key > 0) | |
3647 | { | |
3648 | dist = copy->subs[eq].coef[0]; | |
3649 | dist_v[copy->subs[eq].key - 1] = dist; | |
3650 | } | |
3651 | ||
3652 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3653 | dir_v[j] = dir_from_dist (dist_v[j]); | |
3654 | ||
3655 | save_dist_v (ddr, dist_v); | |
3656 | save_dir_v (ddr, dir_v); | |
3657 | } | |
3658 | ||
3659 | next_problem:; | |
3660 | omega_free_problem (copy); | |
3661 | } | |
3662 | } | |
3663 | ||
3664 | /* This is called for each subscript of a tuple of data references: | |
3665 | insert an equality for representing the conflicts. */ | |
3666 | ||
3667 | static bool | |
3668 | omega_setup_subscript (tree access_fun_a, tree access_fun_b, | |
3669 | struct data_dependence_relation *ddr, | |
3670 | omega_pb pb, bool *maybe_dependent) | |
3671 | { | |
3672 | int eq; | |
33b30201 SP |
3673 | tree type = signed_type_for_types (TREE_TYPE (access_fun_a), |
3674 | TREE_TYPE (access_fun_b)); | |
726a989a RB |
3675 | tree fun_a = chrec_convert (type, access_fun_a, NULL); |
3676 | tree fun_b = chrec_convert (type, access_fun_b, NULL); | |
33b30201 | 3677 | tree difference = chrec_fold_minus (type, fun_a, fun_b); |
5a1f5f9a | 3678 | tree minus_one; |
3d8864c0 SP |
3679 | |
3680 | /* When the fun_a - fun_b is not constant, the dependence is not | |
3681 | captured by the classic distance vector representation. */ | |
3682 | if (TREE_CODE (difference) != INTEGER_CST) | |
3683 | return false; | |
3684 | ||
3685 | /* ZIV test. */ | |
3686 | if (ziv_subscript_p (fun_a, fun_b) && !integer_zerop (difference)) | |
3687 | { | |
3688 | /* There is no dependence. */ | |
3689 | *maybe_dependent = false; | |
3690 | return true; | |
3691 | } | |
3692 | ||
5a1f5f9a SP |
3693 | minus_one = build_int_cst (type, -1); |
3694 | fun_b = chrec_fold_multiply (type, fun_b, minus_one); | |
3d8864c0 SP |
3695 | |
3696 | eq = omega_add_zero_eq (pb, omega_black); | |
3697 | if (!init_omega_eq_with_af (pb, eq, DDR_NB_LOOPS (ddr), fun_a, ddr) | |
3698 | || !init_omega_eq_with_af (pb, eq, 0, fun_b, ddr)) | |
3699 | /* There is probably a dependence, but the system of | |
3700 | constraints cannot be built: answer "don't know". */ | |
3701 | return false; | |
3702 | ||
3703 | /* GCD test. */ | |
3704 | if (DDR_NB_LOOPS (ddr) != 0 && pb->eqs[eq].coef[0] | |
b8698a0f | 3705 | && !int_divides_p (lambda_vector_gcd |
3d8864c0 SP |
3706 | ((lambda_vector) &(pb->eqs[eq].coef[1]), |
3707 | 2 * DDR_NB_LOOPS (ddr)), | |
3708 | pb->eqs[eq].coef[0])) | |
3709 | { | |
3710 | /* There is no dependence. */ | |
3711 | *maybe_dependent = false; | |
3712 | return true; | |
3713 | } | |
3714 | ||
3715 | return true; | |
3716 | } | |
3717 | ||
3718 | /* Helper function, same as init_omega_for_ddr but specialized for | |
3719 | data references A and B. */ | |
3720 | ||
3721 | static bool | |
3722 | init_omega_for_ddr_1 (struct data_reference *dra, struct data_reference *drb, | |
3723 | struct data_dependence_relation *ddr, | |
3724 | omega_pb pb, bool *maybe_dependent) | |
3725 | { | |
3726 | unsigned i; | |
3727 | int ineq; | |
3728 | struct loop *loopi; | |
3729 | unsigned nb_loops = DDR_NB_LOOPS (ddr); | |
3730 | ||
3731 | /* Insert an equality per subscript. */ | |
3732 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3733 | { | |
3734 | if (!omega_setup_subscript (DR_ACCESS_FN (dra, i), DR_ACCESS_FN (drb, i), | |
3735 | ddr, pb, maybe_dependent)) | |
3736 | return false; | |
3737 | else if (*maybe_dependent == false) | |
3738 | { | |
3739 | /* There is no dependence. */ | |
3740 | DDR_ARE_DEPENDENT (ddr) = chrec_known; | |
3741 | return true; | |
3742 | } | |
3743 | } | |
3744 | ||
3745 | /* Insert inequalities: constraints corresponding to the iteration | |
3746 | domain, i.e. the loops surrounding the references "loop_x" and | |
3747 | the distance variables "dx". The layout of the OMEGA | |
3748 | representation is as follows: | |
3749 | - coef[0] is the constant | |
3750 | - coef[1..nb_loops] are the protected variables that will not be | |
3751 | removed by the solver: the "dx" | |
3752 | - coef[nb_loops + 1, 2*nb_loops] are the loop variables: "loop_x". | |
3753 | */ | |
b8698a0f | 3754 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
3d8864c0 SP |
3755 | && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++) |
3756 | { | |
fd727b34 | 3757 | HOST_WIDE_INT nbi = estimated_loop_iterations_int (loopi, false); |
3d8864c0 SP |
3758 | |
3759 | /* 0 <= loop_x */ | |
3760 | ineq = omega_add_zero_geq (pb, omega_black); | |
3761 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3762 | ||
3763 | /* 0 <= loop_x + dx */ | |
3764 | ineq = omega_add_zero_geq (pb, omega_black); | |
3765 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3766 | pb->geqs[ineq].coef[i + 1] = 1; | |
3767 | ||
3768 | if (nbi != -1) | |
3769 | { | |
3770 | /* loop_x <= nb_iters */ | |
3771 | ineq = omega_add_zero_geq (pb, omega_black); | |
3772 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3773 | pb->geqs[ineq].coef[0] = nbi; | |
3774 | ||
3775 | /* loop_x + dx <= nb_iters */ | |
3776 | ineq = omega_add_zero_geq (pb, omega_black); | |
3777 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3778 | pb->geqs[ineq].coef[i + 1] = -1; | |
3779 | pb->geqs[ineq].coef[0] = nbi; | |
3780 | ||
3781 | /* A step "dx" bigger than nb_iters is not feasible, so | |
3782 | add "0 <= nb_iters + dx", */ | |
3783 | ineq = omega_add_zero_geq (pb, omega_black); | |
3784 | pb->geqs[ineq].coef[i + 1] = 1; | |
3785 | pb->geqs[ineq].coef[0] = nbi; | |
3786 | /* and "dx <= nb_iters". */ | |
3787 | ineq = omega_add_zero_geq (pb, omega_black); | |
3788 | pb->geqs[ineq].coef[i + 1] = -1; | |
3789 | pb->geqs[ineq].coef[0] = nbi; | |
3790 | } | |
3791 | } | |
3792 | ||
3793 | omega_extract_distance_vectors (pb, ddr); | |
3794 | ||
3795 | return true; | |
3796 | } | |
3797 | ||
3798 | /* Sets up the Omega dependence problem for the data dependence | |
3799 | relation DDR. Returns false when the constraint system cannot be | |
3800 | built, ie. when the test answers "don't know". Returns true | |
3801 | otherwise, and when independence has been proved (using one of the | |
3802 | trivial dependence test), set MAYBE_DEPENDENT to false, otherwise | |
3803 | set MAYBE_DEPENDENT to true. | |
3804 | ||
3805 | Example: for setting up the dependence system corresponding to the | |
b8698a0f | 3806 | conflicting accesses |
3d8864c0 SP |
3807 | |
3808 | | loop_i | |
3809 | | loop_j | |
3810 | | A[i, i+1] = ... | |
3811 | | ... A[2*j, 2*(i + j)] | |
3812 | | endloop_j | |
3813 | | endloop_i | |
b8698a0f | 3814 | |
3d8864c0 SP |
3815 | the following constraints come from the iteration domain: |
3816 | ||
3817 | 0 <= i <= Ni | |
3818 | 0 <= i + di <= Ni | |
3819 | 0 <= j <= Nj | |
3820 | 0 <= j + dj <= Nj | |
3821 | ||
3822 | where di, dj are the distance variables. The constraints | |
3823 | representing the conflicting elements are: | |
3824 | ||
3825 | i = 2 * (j + dj) | |
3826 | i + 1 = 2 * (i + di + j + dj) | |
3827 | ||
3828 | For asking that the resulting distance vector (di, dj) be | |
3829 | lexicographically positive, we insert the constraint "di >= 0". If | |
3830 | "di = 0" in the solution, we fix that component to zero, and we | |
3831 | look at the inner loops: we set a new problem where all the outer | |
3832 | loop distances are zero, and fix this inner component to be | |
3833 | positive. When one of the components is positive, we save that | |
3834 | distance, and set a new problem where the distance on this loop is | |
3835 | zero, searching for other distances in the inner loops. Here is | |
3836 | the classic example that illustrates that we have to set for each | |
3837 | inner loop a new problem: | |
3838 | ||
3839 | | loop_1 | |
3840 | | loop_2 | |
3841 | | A[10] | |
3842 | | endloop_2 | |
3843 | | endloop_1 | |
3844 | ||
3845 | we have to save two distances (1, 0) and (0, 1). | |
3846 | ||
3847 | Given two array references, refA and refB, we have to set the | |
3848 | dependence problem twice, refA vs. refB and refB vs. refA, and we | |
3849 | cannot do a single test, as refB might occur before refA in the | |
3850 | inner loops, and the contrary when considering outer loops: ex. | |
3851 | ||
3852 | | loop_0 | |
3853 | | loop_1 | |
3854 | | loop_2 | |
3855 | | T[{1,+,1}_2][{1,+,1}_1] // refA | |
3856 | | T[{2,+,1}_2][{0,+,1}_1] // refB | |
3857 | | endloop_2 | |
3858 | | endloop_1 | |
3859 | | endloop_0 | |
3860 | ||
3861 | refB touches the elements in T before refA, and thus for the same | |
3862 | loop_0 refB precedes refA: ie. the distance vector (0, 1, -1) | |
3863 | but for successive loop_0 iterations, we have (1, -1, 1) | |
3864 | ||
3865 | The Omega solver expects the distance variables ("di" in the | |
3866 | previous example) to come first in the constraint system (as | |
3867 | variables to be protected, or "safe" variables), the constraint | |
3868 | system is built using the following layout: | |
3869 | ||
3870 | "cst | distance vars | index vars". | |
3871 | */ | |
3872 | ||
3873 | static bool | |
3874 | init_omega_for_ddr (struct data_dependence_relation *ddr, | |
3875 | bool *maybe_dependent) | |
3876 | { | |
3877 | omega_pb pb; | |
3878 | bool res = false; | |
3879 | ||
3880 | *maybe_dependent = true; | |
3881 | ||
3882 | if (same_access_functions (ddr)) | |
3883 | { | |
3884 | unsigned j; | |
3885 | lambda_vector dir_v; | |
3886 | ||
3887 | /* Save the 0 vector. */ | |
3888 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
3889 | dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3890 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3891 | dir_v[j] = dir_equal; | |
3892 | save_dir_v (ddr, dir_v); | |
3893 | ||
3894 | /* Save the dependences carried by outer loops. */ | |
3895 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
3896 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
3897 | maybe_dependent); | |
3898 | omega_free_problem (pb); | |
3899 | return res; | |
3900 | } | |
3901 | ||
3902 | /* Omega expects the protected variables (those that have to be kept | |
3903 | after elimination) to appear first in the constraint system. | |
3904 | These variables are the distance variables. In the following | |
3905 | initialization we declare NB_LOOPS safe variables, and the total | |
3906 | number of variables for the constraint system is 2*NB_LOOPS. */ | |
3907 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
3908 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
3909 | maybe_dependent); | |
3910 | omega_free_problem (pb); | |
3911 | ||
3912 | /* Stop computation if not decidable, or no dependence. */ | |
3913 | if (res == false || *maybe_dependent == false) | |
3914 | return res; | |
3915 | ||
3916 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
3917 | res = init_omega_for_ddr_1 (DDR_B (ddr), DDR_A (ddr), ddr, pb, | |
3918 | maybe_dependent); | |
3919 | omega_free_problem (pb); | |
3920 | ||
3921 | return res; | |
3922 | } | |
3923 | ||
3924 | /* Return true when DDR contains the same information as that stored | |
3925 | in DIR_VECTS and in DIST_VECTS, return false otherwise. */ | |
3926 | ||
3927 | static bool | |
3928 | ddr_consistent_p (FILE *file, | |
3929 | struct data_dependence_relation *ddr, | |
3930 | VEC (lambda_vector, heap) *dist_vects, | |
3931 | VEC (lambda_vector, heap) *dir_vects) | |
3932 | { | |
3933 | unsigned int i, j; | |
3934 | ||
3935 | /* If dump_file is set, output there. */ | |
3936 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3937 | file = dump_file; | |
3938 | ||
3939 | if (VEC_length (lambda_vector, dist_vects) != DDR_NUM_DIST_VECTS (ddr)) | |
3940 | { | |
3941 | lambda_vector b_dist_v; | |
3942 | fprintf (file, "\n(Number of distance vectors differ: Banerjee has %d, Omega has %d.\n", | |
3943 | VEC_length (lambda_vector, dist_vects), | |
3944 | DDR_NUM_DIST_VECTS (ddr)); | |
3945 | ||
3946 | fprintf (file, "Banerjee dist vectors:\n"); | |
ac47786e | 3947 | FOR_EACH_VEC_ELT (lambda_vector, dist_vects, i, b_dist_v) |
3d8864c0 SP |
3948 | print_lambda_vector (file, b_dist_v, DDR_NB_LOOPS (ddr)); |
3949 | ||
3950 | fprintf (file, "Omega dist vectors:\n"); | |
3951 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3952 | print_lambda_vector (file, DDR_DIST_VECT (ddr, i), DDR_NB_LOOPS (ddr)); | |
3953 | ||
3954 | fprintf (file, "data dependence relation:\n"); | |
3955 | dump_data_dependence_relation (file, ddr); | |
3956 | ||
3957 | fprintf (file, ")\n"); | |
3958 | return false; | |
3959 | } | |
3960 | ||
3961 | if (VEC_length (lambda_vector, dir_vects) != DDR_NUM_DIR_VECTS (ddr)) | |
3962 | { | |
3963 | fprintf (file, "\n(Number of direction vectors differ: Banerjee has %d, Omega has %d.)\n", | |
3964 | VEC_length (lambda_vector, dir_vects), | |
3965 | DDR_NUM_DIR_VECTS (ddr)); | |
3966 | return false; | |
3967 | } | |
3968 | ||
3969 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3970 | { | |
3971 | lambda_vector a_dist_v; | |
3972 | lambda_vector b_dist_v = DDR_DIST_VECT (ddr, i); | |
3973 | ||
3974 | /* Distance vectors are not ordered in the same way in the DDR | |
3975 | and in the DIST_VECTS: search for a matching vector. */ | |
ac47786e | 3976 | FOR_EACH_VEC_ELT (lambda_vector, dist_vects, j, a_dist_v) |
3d8864c0 SP |
3977 | if (lambda_vector_equal (a_dist_v, b_dist_v, DDR_NB_LOOPS (ddr))) |
3978 | break; | |
3979 | ||
3980 | if (j == VEC_length (lambda_vector, dist_vects)) | |
3981 | { | |
3982 | fprintf (file, "\n(Dist vectors from the first dependence analyzer:\n"); | |
3983 | print_dist_vectors (file, dist_vects, DDR_NB_LOOPS (ddr)); | |
3984 | fprintf (file, "not found in Omega dist vectors:\n"); | |
3985 | print_dist_vectors (file, DDR_DIST_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
3986 | fprintf (file, "data dependence relation:\n"); | |
3987 | dump_data_dependence_relation (file, ddr); | |
3988 | fprintf (file, ")\n"); | |
3989 | } | |
3990 | } | |
3991 | ||
3992 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
3993 | { | |
3994 | lambda_vector a_dir_v; | |
3995 | lambda_vector b_dir_v = DDR_DIR_VECT (ddr, i); | |
3996 | ||
3997 | /* Direction vectors are not ordered in the same way in the DDR | |
3998 | and in the DIR_VECTS: search for a matching vector. */ | |
ac47786e | 3999 | FOR_EACH_VEC_ELT (lambda_vector, dir_vects, j, a_dir_v) |
3d8864c0 SP |
4000 | if (lambda_vector_equal (a_dir_v, b_dir_v, DDR_NB_LOOPS (ddr))) |
4001 | break; | |
4002 | ||
4003 | if (j == VEC_length (lambda_vector, dist_vects)) | |
4004 | { | |
4005 | fprintf (file, "\n(Dir vectors from the first dependence analyzer:\n"); | |
4006 | print_dir_vectors (file, dir_vects, DDR_NB_LOOPS (ddr)); | |
4007 | fprintf (file, "not found in Omega dir vectors:\n"); | |
4008 | print_dir_vectors (file, DDR_DIR_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4009 | fprintf (file, "data dependence relation:\n"); | |
4010 | dump_data_dependence_relation (file, ddr); | |
4011 | fprintf (file, ")\n"); | |
4012 | } | |
4013 | } | |
4014 | ||
b8698a0f | 4015 | return true; |
3d8864c0 SP |
4016 | } |
4017 | ||
da9a21f4 SP |
4018 | /* This computes the affine dependence relation between A and B with |
4019 | respect to LOOP_NEST. CHREC_KNOWN is used for representing the | |
4020 | independence between two accesses, while CHREC_DONT_KNOW is used | |
4021 | for representing the unknown relation. | |
b8698a0f | 4022 | |
56cf8686 SP |
4023 | Note that it is possible to stop the computation of the dependence |
4024 | relation the first time we detect a CHREC_KNOWN element for a given | |
4025 | subscript. */ | |
4026 | ||
0ff4040e | 4027 | static void |
da9a21f4 SP |
4028 | compute_affine_dependence (struct data_dependence_relation *ddr, |
4029 | struct loop *loop_nest) | |
56cf8686 SP |
4030 | { |
4031 | struct data_reference *dra = DDR_A (ddr); | |
4032 | struct data_reference *drb = DDR_B (ddr); | |
b8698a0f | 4033 | |
56cf8686 SP |
4034 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4035 | { | |
36d59cf7 | 4036 | fprintf (dump_file, "(compute_affine_dependence\n"); |
56cf8686 | 4037 | fprintf (dump_file, " (stmt_a = \n"); |
726a989a | 4038 | print_gimple_stmt (dump_file, DR_STMT (dra), 0, 0); |
56cf8686 | 4039 | fprintf (dump_file, ")\n (stmt_b = \n"); |
726a989a | 4040 | print_gimple_stmt (dump_file, DR_STMT (drb), 0, 0); |
56cf8686 SP |
4041 | fprintf (dump_file, ")\n"); |
4042 | } | |
0ff4040e | 4043 | |
56cf8686 | 4044 | /* Analyze only when the dependence relation is not yet known. */ |
b3924be9 SP |
4045 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE |
4046 | && !DDR_SELF_REFERENCE (ddr)) | |
56cf8686 | 4047 | { |
0ff4040e SP |
4048 | dependence_stats.num_dependence_tests++; |
4049 | ||
da9a21f4 SP |
4050 | if (access_functions_are_affine_or_constant_p (dra, loop_nest) |
4051 | && access_functions_are_affine_or_constant_p (drb, loop_nest)) | |
3d8864c0 SP |
4052 | { |
4053 | if (flag_check_data_deps) | |
4054 | { | |
4055 | /* Compute the dependences using the first algorithm. */ | |
da9a21f4 | 4056 | subscript_dependence_tester (ddr, loop_nest); |
3d8864c0 SP |
4057 | |
4058 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4059 | { | |
4060 | fprintf (dump_file, "\n\nBanerjee Analyzer\n"); | |
4061 | dump_data_dependence_relation (dump_file, ddr); | |
4062 | } | |
4063 | ||
4064 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
4065 | { | |
4066 | bool maybe_dependent; | |
4067 | VEC (lambda_vector, heap) *dir_vects, *dist_vects; | |
4068 | ||
4069 | /* Save the result of the first DD analyzer. */ | |
4070 | dist_vects = DDR_DIST_VECTS (ddr); | |
4071 | dir_vects = DDR_DIR_VECTS (ddr); | |
4072 | ||
4073 | /* Reset the information. */ | |
4074 | DDR_DIST_VECTS (ddr) = NULL; | |
4075 | DDR_DIR_VECTS (ddr) = NULL; | |
4076 | ||
4077 | /* Compute the same information using Omega. */ | |
4078 | if (!init_omega_for_ddr (ddr, &maybe_dependent)) | |
4079 | goto csys_dont_know; | |
4080 | ||
4081 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4082 | { | |
4083 | fprintf (dump_file, "Omega Analyzer\n"); | |
4084 | dump_data_dependence_relation (dump_file, ddr); | |
4085 | } | |
4086 | ||
4087 | /* Check that we get the same information. */ | |
4088 | if (maybe_dependent) | |
4089 | gcc_assert (ddr_consistent_p (stderr, ddr, dist_vects, | |
4090 | dir_vects)); | |
4091 | } | |
4092 | } | |
4093 | else | |
da9a21f4 | 4094 | subscript_dependence_tester (ddr, loop_nest); |
3d8864c0 | 4095 | } |
b8698a0f | 4096 | |
56cf8686 SP |
4097 | /* As a last case, if the dependence cannot be determined, or if |
4098 | the dependence is considered too difficult to determine, answer | |
4099 | "don't know". */ | |
4100 | else | |
0ff4040e | 4101 | { |
3d8864c0 | 4102 | csys_dont_know:; |
0ff4040e SP |
4103 | dependence_stats.num_dependence_undetermined++; |
4104 | ||
4105 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4106 | { | |
4107 | fprintf (dump_file, "Data ref a:\n"); | |
4108 | dump_data_reference (dump_file, dra); | |
4109 | fprintf (dump_file, "Data ref b:\n"); | |
4110 | dump_data_reference (dump_file, drb); | |
4111 | fprintf (dump_file, "affine dependence test not usable: access function not affine or constant.\n"); | |
4112 | } | |
4113 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
4114 | } | |
56cf8686 | 4115 | } |
b8698a0f | 4116 | |
56cf8686 SP |
4117 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4118 | fprintf (dump_file, ")\n"); | |
4119 | } | |
4120 | ||
789246d7 SP |
4121 | /* This computes the dependence relation for the same data |
4122 | reference into DDR. */ | |
4123 | ||
4124 | static void | |
4125 | compute_self_dependence (struct data_dependence_relation *ddr) | |
4126 | { | |
4127 | unsigned int i; | |
ebf78a47 | 4128 | struct subscript *subscript; |
789246d7 | 4129 | |
3cb960c7 ZD |
4130 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
4131 | return; | |
4132 | ||
ebf78a47 SP |
4133 | for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript); |
4134 | i++) | |
789246d7 | 4135 | { |
6935bae7 SP |
4136 | if (SUB_CONFLICTS_IN_A (subscript)) |
4137 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
4138 | if (SUB_CONFLICTS_IN_B (subscript)) | |
4139 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
4140 | ||
789246d7 | 4141 | /* The accessed index overlaps for each iteration. */ |
d93817c4 | 4142 | SUB_CONFLICTS_IN_A (subscript) |
6935bae7 | 4143 | = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
d93817c4 | 4144 | SUB_CONFLICTS_IN_B (subscript) |
6935bae7 | 4145 | = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
789246d7 SP |
4146 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
4147 | } | |
789246d7 | 4148 | |
0ff4040e | 4149 | /* The distance vector is the zero vector. */ |
ba42e045 SP |
4150 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); |
4151 | save_dir_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
0ff4040e | 4152 | } |
7b8a92e1 | 4153 | |
ba42e045 SP |
4154 | /* Compute in DEPENDENCE_RELATIONS the data dependence graph for all |
4155 | the data references in DATAREFS, in the LOOP_NEST. When | |
ebf78a47 SP |
4156 | COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self |
4157 | relations. */ | |
56cf8686 | 4158 | |
b8698a0f | 4159 | void |
ebf78a47 | 4160 | compute_all_dependences (VEC (data_reference_p, heap) *datarefs, |
a84481aa | 4161 | VEC (ddr_p, heap) **dependence_relations, |
ba42e045 | 4162 | VEC (loop_p, heap) *loop_nest, |
ebf78a47 | 4163 | bool compute_self_and_rr) |
56cf8686 | 4164 | { |
ebf78a47 SP |
4165 | struct data_dependence_relation *ddr; |
4166 | struct data_reference *a, *b; | |
4167 | unsigned int i, j; | |
56cf8686 | 4168 | |
ac47786e | 4169 | FOR_EACH_VEC_ELT (data_reference_p, datarefs, i, a) |
ebf78a47 | 4170 | for (j = i + 1; VEC_iterate (data_reference_p, datarefs, j, b); j++) |
b0af49c4 | 4171 | if (DR_IS_WRITE (a) || DR_IS_WRITE (b) || compute_self_and_rr) |
ebf78a47 SP |
4172 | { |
4173 | ddr = initialize_data_dependence_relation (a, b, loop_nest); | |
a84481aa | 4174 | VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); |
a70d6342 IR |
4175 | if (loop_nest) |
4176 | compute_affine_dependence (ddr, VEC_index (loop_p, loop_nest, 0)); | |
ebf78a47 | 4177 | } |
789246d7 | 4178 | |
ebf78a47 | 4179 | if (compute_self_and_rr) |
ac47786e | 4180 | FOR_EACH_VEC_ELT (data_reference_p, datarefs, i, a) |
56cf8686 | 4181 | { |
ebf78a47 | 4182 | ddr = initialize_data_dependence_relation (a, a, loop_nest); |
a84481aa | 4183 | VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); |
ebf78a47 | 4184 | compute_self_dependence (ddr); |
56cf8686 SP |
4185 | } |
4186 | } | |
4187 | ||
946e1bc7 ZD |
4188 | /* Stores the locations of memory references in STMT to REFERENCES. Returns |
4189 | true if STMT clobbers memory, false otherwise. */ | |
4190 | ||
4191 | bool | |
726a989a | 4192 | get_references_in_stmt (gimple stmt, VEC (data_ref_loc, heap) **references) |
946e1bc7 ZD |
4193 | { |
4194 | bool clobbers_memory = false; | |
4195 | data_ref_loc *ref; | |
726a989a RB |
4196 | tree *op0, *op1; |
4197 | enum gimple_code stmt_code = gimple_code (stmt); | |
946e1bc7 ZD |
4198 | |
4199 | *references = NULL; | |
4200 | ||
4201 | /* ASM_EXPR and CALL_EXPR may embed arbitrary side effects. | |
4202 | Calls have side-effects, except those to const or pure | |
4203 | functions. */ | |
726a989a RB |
4204 | if ((stmt_code == GIMPLE_CALL |
4205 | && !(gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE))) | |
4206 | || (stmt_code == GIMPLE_ASM | |
4207 | && gimple_asm_volatile_p (stmt))) | |
946e1bc7 ZD |
4208 | clobbers_memory = true; |
4209 | ||
5006671f | 4210 | if (!gimple_vuse (stmt)) |
946e1bc7 ZD |
4211 | return clobbers_memory; |
4212 | ||
726a989a | 4213 | if (stmt_code == GIMPLE_ASSIGN) |
946e1bc7 | 4214 | { |
c8ae0bec | 4215 | tree base; |
726a989a RB |
4216 | op0 = gimple_assign_lhs_ptr (stmt); |
4217 | op1 = gimple_assign_rhs1_ptr (stmt); | |
b8698a0f | 4218 | |
946e1bc7 | 4219 | if (DECL_P (*op1) |
c8ae0bec RG |
4220 | || (REFERENCE_CLASS_P (*op1) |
4221 | && (base = get_base_address (*op1)) | |
4222 | && TREE_CODE (base) != SSA_NAME)) | |
946e1bc7 ZD |
4223 | { |
4224 | ref = VEC_safe_push (data_ref_loc, heap, *references, NULL); | |
4225 | ref->pos = op1; | |
4226 | ref->is_read = true; | |
4227 | } | |
4228 | ||
4229 | if (DECL_P (*op0) | |
0976ffb6 | 4230 | || (REFERENCE_CLASS_P (*op0) && get_base_address (*op0))) |
946e1bc7 ZD |
4231 | { |
4232 | ref = VEC_safe_push (data_ref_loc, heap, *references, NULL); | |
4233 | ref->pos = op0; | |
4234 | ref->is_read = false; | |
4235 | } | |
4236 | } | |
726a989a | 4237 | else if (stmt_code == GIMPLE_CALL) |
946e1bc7 | 4238 | { |
726a989a | 4239 | unsigned i, n = gimple_call_num_args (stmt); |
ac84e05e ZD |
4240 | |
4241 | for (i = 0; i < n; i++) | |
946e1bc7 | 4242 | { |
726a989a | 4243 | op0 = gimple_call_arg_ptr (stmt, i); |
ac84e05e | 4244 | |
946e1bc7 | 4245 | if (DECL_P (*op0) |
0976ffb6 | 4246 | || (REFERENCE_CLASS_P (*op0) && get_base_address (*op0))) |
946e1bc7 ZD |
4247 | { |
4248 | ref = VEC_safe_push (data_ref_loc, heap, *references, NULL); | |
4249 | ref->pos = op0; | |
4250 | ref->is_read = true; | |
4251 | } | |
4252 | } | |
4253 | } | |
4254 | ||
4255 | return clobbers_memory; | |
4256 | } | |
4257 | ||
4258 | /* Stores the data references in STMT to DATAREFS. If there is an unanalyzable | |
3cb960c7 | 4259 | reference, returns false, otherwise returns true. NEST is the outermost |
f8bf9252 | 4260 | loop of the loop nest in which the references should be analyzed. */ |
946e1bc7 | 4261 | |
f8bf9252 | 4262 | bool |
726a989a | 4263 | find_data_references_in_stmt (struct loop *nest, gimple stmt, |
946e1bc7 ZD |
4264 | VEC (data_reference_p, heap) **datarefs) |
4265 | { | |
4266 | unsigned i; | |
4267 | VEC (data_ref_loc, heap) *references; | |
4268 | data_ref_loc *ref; | |
4269 | bool ret = true; | |
4270 | data_reference_p dr; | |
4271 | ||
4272 | if (get_references_in_stmt (stmt, &references)) | |
4273 | { | |
4274 | VEC_free (data_ref_loc, heap, references); | |
4275 | return false; | |
4276 | } | |
4277 | ||
ac47786e | 4278 | FOR_EACH_VEC_ELT (data_ref_loc, references, i, ref) |
946e1bc7 | 4279 | { |
5c640e29 SP |
4280 | dr = create_data_ref (nest, loop_containing_stmt (stmt), |
4281 | *ref->pos, stmt, ref->is_read); | |
bbc8a8dc | 4282 | gcc_assert (dr != NULL); |
b8698a0f L |
4283 | |
4284 | /* FIXME -- data dependence analysis does not work correctly for objects | |
a70d6342 IR |
4285 | with invariant addresses in loop nests. Let us fail here until the |
4286 | problem is fixed. */ | |
4287 | if (dr_address_invariant_p (dr) && nest) | |
946e1bc7 | 4288 | { |
bbc8a8dc ZD |
4289 | free_data_ref (dr); |
4290 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4291 | fprintf (dump_file, "\tFAILED as dr address is invariant\n"); | |
946e1bc7 ZD |
4292 | ret = false; |
4293 | break; | |
4294 | } | |
bbc8a8dc ZD |
4295 | |
4296 | VEC_safe_push (data_reference_p, heap, *datarefs, dr); | |
946e1bc7 ZD |
4297 | } |
4298 | VEC_free (data_ref_loc, heap, references); | |
4299 | return ret; | |
4300 | } | |
4301 | ||
5c640e29 SP |
4302 | /* Stores the data references in STMT to DATAREFS. If there is an |
4303 | unanalyzable reference, returns false, otherwise returns true. | |
4304 | NEST is the outermost loop of the loop nest in which the references | |
4305 | should be instantiated, LOOP is the loop in which the references | |
4306 | should be analyzed. */ | |
ed91d661 SP |
4307 | |
4308 | bool | |
5c640e29 | 4309 | graphite_find_data_references_in_stmt (loop_p nest, loop_p loop, gimple stmt, |
ed91d661 SP |
4310 | VEC (data_reference_p, heap) **datarefs) |
4311 | { | |
4312 | unsigned i; | |
4313 | VEC (data_ref_loc, heap) *references; | |
4314 | data_ref_loc *ref; | |
4315 | bool ret = true; | |
4316 | data_reference_p dr; | |
4317 | ||
4318 | if (get_references_in_stmt (stmt, &references)) | |
4319 | { | |
4320 | VEC_free (data_ref_loc, heap, references); | |
4321 | return false; | |
4322 | } | |
4323 | ||
ac47786e | 4324 | FOR_EACH_VEC_ELT (data_ref_loc, references, i, ref) |
ed91d661 | 4325 | { |
5c640e29 | 4326 | dr = create_data_ref (nest, loop, *ref->pos, stmt, ref->is_read); |
ed91d661 SP |
4327 | gcc_assert (dr != NULL); |
4328 | VEC_safe_push (data_reference_p, heap, *datarefs, dr); | |
4329 | } | |
4330 | ||
4331 | VEC_free (data_ref_loc, heap, references); | |
4332 | return ret; | |
4333 | } | |
4334 | ||
a70d6342 IR |
4335 | /* Search the data references in LOOP, and record the information into |
4336 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4337 | difficult case, returns NULL_TREE otherwise. */ | |
4338 | ||
bfe068c3 | 4339 | tree |
a70d6342 IR |
4340 | find_data_references_in_bb (struct loop *loop, basic_block bb, |
4341 | VEC (data_reference_p, heap) **datarefs) | |
4342 | { | |
4343 | gimple_stmt_iterator bsi; | |
4344 | ||
4345 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
4346 | { | |
4347 | gimple stmt = gsi_stmt (bsi); | |
4348 | ||
4349 | if (!find_data_references_in_stmt (loop, stmt, datarefs)) | |
4350 | { | |
4351 | struct data_reference *res; | |
4352 | res = XCNEW (struct data_reference); | |
4353 | VEC_safe_push (data_reference_p, heap, *datarefs, res); | |
4354 | ||
4355 | return chrec_dont_know; | |
4356 | } | |
4357 | } | |
4358 | ||
4359 | return NULL_TREE; | |
4360 | } | |
4361 | ||
56cf8686 SP |
4362 | /* Search the data references in LOOP, and record the information into |
4363 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4364 | difficult case, returns NULL_TREE otherwise. | |
3cb960c7 | 4365 | |
464f49d8 DB |
4366 | TODO: This function should be made smarter so that it can handle address |
4367 | arithmetic as if they were array accesses, etc. */ | |
56cf8686 | 4368 | |
b8698a0f | 4369 | tree |
ebf78a47 | 4370 | find_data_references_in_loop (struct loop *loop, |
e14b10df | 4371 | VEC (data_reference_p, heap) **datarefs) |
56cf8686 | 4372 | { |
ccbdbf0a JL |
4373 | basic_block bb, *bbs; |
4374 | unsigned int i; | |
86df10e3 | 4375 | |
bbc8a8dc | 4376 | bbs = get_loop_body_in_dom_order (loop); |
ccbdbf0a JL |
4377 | |
4378 | for (i = 0; i < loop->num_nodes; i++) | |
56cf8686 | 4379 | { |
ccbdbf0a JL |
4380 | bb = bbs[i]; |
4381 | ||
a70d6342 IR |
4382 | if (find_data_references_in_bb (loop, bb, datarefs) == chrec_dont_know) |
4383 | { | |
4384 | free (bbs); | |
4385 | return chrec_dont_know; | |
4386 | } | |
56cf8686 | 4387 | } |
ccbdbf0a JL |
4388 | free (bbs); |
4389 | ||
4aad410d | 4390 | return NULL_TREE; |
56cf8686 SP |
4391 | } |
4392 | ||
ba42e045 SP |
4393 | /* Recursive helper function. */ |
4394 | ||
4395 | static bool | |
3ac57120 | 4396 | find_loop_nest_1 (struct loop *loop, VEC (loop_p, heap) **loop_nest) |
ba42e045 SP |
4397 | { |
4398 | /* Inner loops of the nest should not contain siblings. Example: | |
4399 | when there are two consecutive loops, | |
4400 | ||
4401 | | loop_0 | |
4402 | | loop_1 | |
4403 | | A[{0, +, 1}_1] | |
4404 | | endloop_1 | |
4405 | | loop_2 | |
4406 | | A[{0, +, 1}_2] | |
4407 | | endloop_2 | |
4408 | | endloop_0 | |
4409 | ||
4410 | the dependence relation cannot be captured by the distance | |
4411 | abstraction. */ | |
4412 | if (loop->next) | |
4413 | return false; | |
56cf8686 | 4414 | |
3ac57120 | 4415 | VEC_safe_push (loop_p, heap, *loop_nest, loop); |
ba42e045 SP |
4416 | if (loop->inner) |
4417 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4418 | return true; | |
4419 | } | |
4420 | ||
4421 | /* Return false when the LOOP is not well nested. Otherwise return | |
4422 | true and insert in LOOP_NEST the loops of the nest. LOOP_NEST will | |
4423 | contain the loops from the outermost to the innermost, as they will | |
4424 | appear in the classic distance vector. */ | |
4425 | ||
5417e022 | 4426 | bool |
3ac57120 | 4427 | find_loop_nest (struct loop *loop, VEC (loop_p, heap) **loop_nest) |
ba42e045 | 4428 | { |
3ac57120 | 4429 | VEC_safe_push (loop_p, heap, *loop_nest, loop); |
ba42e045 SP |
4430 | if (loop->inner) |
4431 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4432 | return true; | |
4433 | } | |
56cf8686 | 4434 | |
9f275479 JS |
4435 | /* Returns true when the data dependences have been computed, false otherwise. |
4436 | Given a loop nest LOOP, the following vectors are returned: | |
b8698a0f L |
4437 | DATAREFS is initialized to all the array elements contained in this loop, |
4438 | DEPENDENCE_RELATIONS contains the relations between the data references. | |
4439 | Compute read-read and self relations if | |
86a07404 | 4440 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ |
56cf8686 | 4441 | |
9f275479 | 4442 | bool |
b8698a0f | 4443 | compute_data_dependences_for_loop (struct loop *loop, |
86a07404 | 4444 | bool compute_self_and_read_read_dependences, |
01be8516 | 4445 | VEC (loop_p, heap) **loop_nest, |
e14b10df SP |
4446 | VEC (data_reference_p, heap) **datarefs, |
4447 | VEC (ddr_p, heap) **dependence_relations) | |
56cf8686 | 4448 | { |
9f275479 | 4449 | bool res = true; |
86a07404 | 4450 | |
0ff4040e | 4451 | memset (&dependence_stats, 0, sizeof (dependence_stats)); |
56cf8686 | 4452 | |
b8698a0f | 4453 | /* If the loop nest is not well formed, or one of the data references |
ba42e045 SP |
4454 | is not computable, give up without spending time to compute other |
4455 | dependences. */ | |
3cb960c7 | 4456 | if (!loop |
01be8516 | 4457 | || !find_loop_nest (loop, loop_nest) |
ba42e045 | 4458 | || find_data_references_in_loop (loop, datarefs) == chrec_dont_know) |
56cf8686 SP |
4459 | { |
4460 | struct data_dependence_relation *ddr; | |
4461 | ||
4462 | /* Insert a single relation into dependence_relations: | |
4463 | chrec_dont_know. */ | |
01be8516 | 4464 | ddr = initialize_data_dependence_relation (NULL, NULL, *loop_nest); |
e14b10df | 4465 | VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); |
9f275479 | 4466 | res = false; |
56cf8686 | 4467 | } |
ba42e045 | 4468 | else |
01be8516 | 4469 | compute_all_dependences (*datarefs, dependence_relations, *loop_nest, |
ebf78a47 | 4470 | compute_self_and_read_read_dependences); |
0ff4040e SP |
4471 | |
4472 | if (dump_file && (dump_flags & TDF_STATS)) | |
56cf8686 | 4473 | { |
0ff4040e SP |
4474 | fprintf (dump_file, "Dependence tester statistics:\n"); |
4475 | ||
b8698a0f | 4476 | fprintf (dump_file, "Number of dependence tests: %d\n", |
0ff4040e | 4477 | dependence_stats.num_dependence_tests); |
b8698a0f | 4478 | fprintf (dump_file, "Number of dependence tests classified dependent: %d\n", |
0ff4040e | 4479 | dependence_stats.num_dependence_dependent); |
b8698a0f | 4480 | fprintf (dump_file, "Number of dependence tests classified independent: %d\n", |
0ff4040e | 4481 | dependence_stats.num_dependence_independent); |
b8698a0f | 4482 | fprintf (dump_file, "Number of undetermined dependence tests: %d\n", |
0ff4040e SP |
4483 | dependence_stats.num_dependence_undetermined); |
4484 | ||
b8698a0f | 4485 | fprintf (dump_file, "Number of subscript tests: %d\n", |
0ff4040e | 4486 | dependence_stats.num_subscript_tests); |
b8698a0f | 4487 | fprintf (dump_file, "Number of undetermined subscript tests: %d\n", |
0ff4040e | 4488 | dependence_stats.num_subscript_undetermined); |
b8698a0f | 4489 | fprintf (dump_file, "Number of same subscript function: %d\n", |
0ff4040e SP |
4490 | dependence_stats.num_same_subscript_function); |
4491 | ||
4492 | fprintf (dump_file, "Number of ziv tests: %d\n", | |
4493 | dependence_stats.num_ziv); | |
4494 | fprintf (dump_file, "Number of ziv tests returning dependent: %d\n", | |
4495 | dependence_stats.num_ziv_dependent); | |
4496 | fprintf (dump_file, "Number of ziv tests returning independent: %d\n", | |
4497 | dependence_stats.num_ziv_independent); | |
4498 | fprintf (dump_file, "Number of ziv tests unimplemented: %d\n", | |
b8698a0f | 4499 | dependence_stats.num_ziv_unimplemented); |
0ff4040e | 4500 | |
b8698a0f | 4501 | fprintf (dump_file, "Number of siv tests: %d\n", |
0ff4040e SP |
4502 | dependence_stats.num_siv); |
4503 | fprintf (dump_file, "Number of siv tests returning dependent: %d\n", | |
4504 | dependence_stats.num_siv_dependent); | |
4505 | fprintf (dump_file, "Number of siv tests returning independent: %d\n", | |
4506 | dependence_stats.num_siv_independent); | |
4507 | fprintf (dump_file, "Number of siv tests unimplemented: %d\n", | |
4508 | dependence_stats.num_siv_unimplemented); | |
4509 | ||
b8698a0f | 4510 | fprintf (dump_file, "Number of miv tests: %d\n", |
0ff4040e SP |
4511 | dependence_stats.num_miv); |
4512 | fprintf (dump_file, "Number of miv tests returning dependent: %d\n", | |
4513 | dependence_stats.num_miv_dependent); | |
4514 | fprintf (dump_file, "Number of miv tests returning independent: %d\n", | |
4515 | dependence_stats.num_miv_independent); | |
4516 | fprintf (dump_file, "Number of miv tests unimplemented: %d\n", | |
4517 | dependence_stats.num_miv_unimplemented); | |
9f275479 JS |
4518 | } |
4519 | ||
4520 | return res; | |
56cf8686 SP |
4521 | } |
4522 | ||
b8698a0f | 4523 | /* Returns true when the data dependences for the basic block BB have been |
a70d6342 | 4524 | computed, false otherwise. |
b8698a0f | 4525 | DATAREFS is initialized to all the array elements contained in this basic |
a70d6342 IR |
4526 | block, DEPENDENCE_RELATIONS contains the relations between the data |
4527 | references. Compute read-read and self relations if | |
4528 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ | |
4529 | bool | |
4530 | compute_data_dependences_for_bb (basic_block bb, | |
4531 | bool compute_self_and_read_read_dependences, | |
4532 | VEC (data_reference_p, heap) **datarefs, | |
4533 | VEC (ddr_p, heap) **dependence_relations) | |
4534 | { | |
4535 | if (find_data_references_in_bb (NULL, bb, datarefs) == chrec_dont_know) | |
4536 | return false; | |
4537 | ||
4538 | compute_all_dependences (*datarefs, dependence_relations, NULL, | |
4539 | compute_self_and_read_read_dependences); | |
4540 | return true; | |
4541 | } | |
4542 | ||
56cf8686 | 4543 | /* Entry point (for testing only). Analyze all the data references |
3d8864c0 | 4544 | and the dependence relations in LOOP. |
56cf8686 | 4545 | |
b8698a0f L |
4546 | The data references are computed first. |
4547 | ||
56cf8686 SP |
4548 | A relation on these nodes is represented by a complete graph. Some |
4549 | of the relations could be of no interest, thus the relations can be | |
4550 | computed on demand. | |
b8698a0f | 4551 | |
56cf8686 SP |
4552 | In the following function we compute all the relations. This is |
4553 | just a first implementation that is here for: | |
b8698a0f | 4554 | - for showing how to ask for the dependence relations, |
56cf8686 SP |
4555 | - for the debugging the whole dependence graph, |
4556 | - for the dejagnu testcases and maintenance. | |
b8698a0f | 4557 | |
56cf8686 SP |
4558 | It is possible to ask only for a part of the graph, avoiding to |
4559 | compute the whole dependence graph. The computed dependences are | |
4560 | stored in a knowledge base (KB) such that later queries don't | |
4561 | recompute the same information. The implementation of this KB is | |
4562 | transparent to the optimizer, and thus the KB can be changed with a | |
4563 | more efficient implementation, or the KB could be disabled. */ | |
b8698a0f | 4564 | static void |
3d8864c0 | 4565 | analyze_all_data_dependences (struct loop *loop) |
56cf8686 SP |
4566 | { |
4567 | unsigned int i; | |
56cf8686 | 4568 | int nb_data_refs = 10; |
b8698a0f | 4569 | VEC (data_reference_p, heap) *datarefs = |
ebf78a47 | 4570 | VEC_alloc (data_reference_p, heap, nb_data_refs); |
b8698a0f | 4571 | VEC (ddr_p, heap) *dependence_relations = |
ebf78a47 | 4572 | VEC_alloc (ddr_p, heap, nb_data_refs * nb_data_refs); |
01be8516 | 4573 | VEC (loop_p, heap) *loop_nest = VEC_alloc (loop_p, heap, 3); |
56cf8686 SP |
4574 | |
4575 | /* Compute DDs on the whole function. */ | |
01be8516 | 4576 | compute_data_dependences_for_loop (loop, false, &loop_nest, &datarefs, |
3d8864c0 | 4577 | &dependence_relations); |
56cf8686 SP |
4578 | |
4579 | if (dump_file) | |
4580 | { | |
4581 | dump_data_dependence_relations (dump_file, dependence_relations); | |
4582 | fprintf (dump_file, "\n\n"); | |
56cf8686 | 4583 | |
86df10e3 SP |
4584 | if (dump_flags & TDF_DETAILS) |
4585 | dump_dist_dir_vectors (dump_file, dependence_relations); | |
56cf8686 | 4586 | |
86df10e3 | 4587 | if (dump_flags & TDF_STATS) |
56cf8686 | 4588 | { |
86df10e3 SP |
4589 | unsigned nb_top_relations = 0; |
4590 | unsigned nb_bot_relations = 0; | |
86df10e3 | 4591 | unsigned nb_chrec_relations = 0; |
ebf78a47 | 4592 | struct data_dependence_relation *ddr; |
86df10e3 | 4593 | |
ac47786e | 4594 | FOR_EACH_VEC_ELT (ddr_p, dependence_relations, i, ddr) |
86df10e3 | 4595 | { |
86df10e3 SP |
4596 | if (chrec_contains_undetermined (DDR_ARE_DEPENDENT (ddr))) |
4597 | nb_top_relations++; | |
b8698a0f | 4598 | |
86df10e3 | 4599 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
5006671f | 4600 | nb_bot_relations++; |
b8698a0f L |
4601 | |
4602 | else | |
86df10e3 SP |
4603 | nb_chrec_relations++; |
4604 | } | |
b8698a0f | 4605 | |
86df10e3 SP |
4606 | gather_stats_on_scev_database (); |
4607 | } | |
56cf8686 | 4608 | } |
36d59cf7 | 4609 | |
01be8516 | 4610 | VEC_free (loop_p, heap, loop_nest); |
36d59cf7 DB |
4611 | free_dependence_relations (dependence_relations); |
4612 | free_data_refs (datarefs); | |
4613 | } | |
3d8864c0 SP |
4614 | |
4615 | /* Computes all the data dependences and check that the results of | |
4616 | several analyzers are the same. */ | |
4617 | ||
4618 | void | |
4619 | tree_check_data_deps (void) | |
4620 | { | |
4621 | loop_iterator li; | |
4622 | struct loop *loop_nest; | |
4623 | ||
4624 | FOR_EACH_LOOP (li, loop_nest, 0) | |
4625 | analyze_all_data_dependences (loop_nest); | |
4626 | } | |
36d59cf7 DB |
4627 | |
4628 | /* Free the memory used by a data dependence relation DDR. */ | |
4629 | ||
4630 | void | |
4631 | free_dependence_relation (struct data_dependence_relation *ddr) | |
4632 | { | |
4633 | if (ddr == NULL) | |
4634 | return; | |
4635 | ||
2f470326 | 4636 | if (DDR_SUBSCRIPTS (ddr)) |
d93817c4 | 4637 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
2f470326 JJ |
4638 | if (DDR_DIST_VECTS (ddr)) |
4639 | VEC_free (lambda_vector, heap, DDR_DIST_VECTS (ddr)); | |
4640 | if (DDR_DIR_VECTS (ddr)) | |
4641 | VEC_free (lambda_vector, heap, DDR_DIR_VECTS (ddr)); | |
ebf78a47 | 4642 | |
36d59cf7 DB |
4643 | free (ddr); |
4644 | } | |
4645 | ||
4646 | /* Free the memory used by the data dependence relations from | |
4647 | DEPENDENCE_RELATIONS. */ | |
4648 | ||
b8698a0f | 4649 | void |
ebf78a47 | 4650 | free_dependence_relations (VEC (ddr_p, heap) *dependence_relations) |
36d59cf7 DB |
4651 | { |
4652 | unsigned int i; | |
ebf78a47 | 4653 | struct data_dependence_relation *ddr; |
36d59cf7 | 4654 | |
ac47786e | 4655 | FOR_EACH_VEC_ELT (ddr_p, dependence_relations, i, ddr) |
01be8516 | 4656 | if (ddr) |
3ac57120 | 4657 | free_dependence_relation (ddr); |
ebf78a47 SP |
4658 | |
4659 | VEC_free (ddr_p, heap, dependence_relations); | |
56cf8686 SP |
4660 | } |
4661 | ||
36d59cf7 DB |
4662 | /* Free the memory used by the data references from DATAREFS. */ |
4663 | ||
4664 | void | |
ebf78a47 | 4665 | free_data_refs (VEC (data_reference_p, heap) *datarefs) |
36d59cf7 DB |
4666 | { |
4667 | unsigned int i; | |
ebf78a47 | 4668 | struct data_reference *dr; |
56cf8686 | 4669 | |
ac47786e | 4670 | FOR_EACH_VEC_ELT (data_reference_p, datarefs, i, dr) |
8fdbc9c6 | 4671 | free_data_ref (dr); |
ebf78a47 | 4672 | VEC_free (data_reference_p, heap, datarefs); |
36d59cf7 | 4673 | } |
86df10e3 | 4674 | |
3a796c6f SP |
4675 | \f |
4676 | ||
dea61d92 | 4677 | /* Dump vertex I in RDG to FILE. */ |
3a796c6f | 4678 | |
dea61d92 SP |
4679 | void |
4680 | dump_rdg_vertex (FILE *file, struct graph *rdg, int i) | |
4681 | { | |
4682 | struct vertex *v = &(rdg->vertices[i]); | |
4683 | struct graph_edge *e; | |
4684 | ||
b8698a0f | 4685 | fprintf (file, "(vertex %d: (%s%s) (in:", i, |
dea61d92 SP |
4686 | RDG_MEM_WRITE_STMT (rdg, i) ? "w" : "", |
4687 | RDG_MEM_READS_STMT (rdg, i) ? "r" : ""); | |
4688 | ||
4689 | if (v->pred) | |
4690 | for (e = v->pred; e; e = e->pred_next) | |
4691 | fprintf (file, " %d", e->src); | |
4692 | ||
4693 | fprintf (file, ") (out:"); | |
4694 | ||
4695 | if (v->succ) | |
4696 | for (e = v->succ; e; e = e->succ_next) | |
4697 | fprintf (file, " %d", e->dest); | |
4698 | ||
cfee318d | 4699 | fprintf (file, ")\n"); |
726a989a | 4700 | print_gimple_stmt (file, RDGV_STMT (v), 0, TDF_VOPS|TDF_MEMSYMS); |
dea61d92 SP |
4701 | fprintf (file, ")\n"); |
4702 | } | |
4703 | ||
4704 | /* Call dump_rdg_vertex on stderr. */ | |
4705 | ||
24e47c76 | 4706 | DEBUG_FUNCTION void |
dea61d92 SP |
4707 | debug_rdg_vertex (struct graph *rdg, int i) |
4708 | { | |
4709 | dump_rdg_vertex (stderr, rdg, i); | |
4710 | } | |
4711 | ||
4712 | /* Dump component C of RDG to FILE. If DUMPED is non-null, set the | |
4713 | dumped vertices to that bitmap. */ | |
4714 | ||
4715 | void dump_rdg_component (FILE *file, struct graph *rdg, int c, bitmap dumped) | |
4716 | { | |
4717 | int i; | |
4718 | ||
4719 | fprintf (file, "(%d\n", c); | |
4720 | ||
4721 | for (i = 0; i < rdg->n_vertices; i++) | |
4722 | if (rdg->vertices[i].component == c) | |
4723 | { | |
4724 | if (dumped) | |
4725 | bitmap_set_bit (dumped, i); | |
4726 | ||
4727 | dump_rdg_vertex (file, rdg, i); | |
4728 | } | |
4729 | ||
4730 | fprintf (file, ")\n"); | |
4731 | } | |
4732 | ||
4733 | /* Call dump_rdg_vertex on stderr. */ | |
4734 | ||
24e47c76 | 4735 | DEBUG_FUNCTION void |
dea61d92 SP |
4736 | debug_rdg_component (struct graph *rdg, int c) |
4737 | { | |
4738 | dump_rdg_component (stderr, rdg, c, NULL); | |
4739 | } | |
4740 | ||
4741 | /* Dump the reduced dependence graph RDG to FILE. */ | |
4742 | ||
4743 | void | |
4744 | dump_rdg (FILE *file, struct graph *rdg) | |
3a796c6f SP |
4745 | { |
4746 | int i; | |
dea61d92 SP |
4747 | bitmap dumped = BITMAP_ALLOC (NULL); |
4748 | ||
4749 | fprintf (file, "(rdg\n"); | |
3a796c6f SP |
4750 | |
4751 | for (i = 0; i < rdg->n_vertices; i++) | |
dea61d92 SP |
4752 | if (!bitmap_bit_p (dumped, i)) |
4753 | dump_rdg_component (file, rdg, rdg->vertices[i].component, dumped); | |
3a796c6f | 4754 | |
dea61d92 SP |
4755 | fprintf (file, ")\n"); |
4756 | BITMAP_FREE (dumped); | |
3a796c6f SP |
4757 | } |
4758 | ||
dea61d92 SP |
4759 | /* Call dump_rdg on stderr. */ |
4760 | ||
24e47c76 | 4761 | DEBUG_FUNCTION void |
dea61d92 SP |
4762 | debug_rdg (struct graph *rdg) |
4763 | { | |
4764 | dump_rdg (stderr, rdg); | |
4765 | } | |
3a796c6f | 4766 | |
f3241b29 SP |
4767 | static void |
4768 | dot_rdg_1 (FILE *file, struct graph *rdg) | |
4769 | { | |
4770 | int i; | |
4771 | ||
4772 | fprintf (file, "digraph RDG {\n"); | |
4773 | ||
4774 | for (i = 0; i < rdg->n_vertices; i++) | |
4775 | { | |
4776 | struct vertex *v = &(rdg->vertices[i]); | |
4777 | struct graph_edge *e; | |
4778 | ||
4779 | /* Highlight reads from memory. */ | |
4780 | if (RDG_MEM_READS_STMT (rdg, i)) | |
4781 | fprintf (file, "%d [style=filled, fillcolor=green]\n", i); | |
4782 | ||
4783 | /* Highlight stores to memory. */ | |
4784 | if (RDG_MEM_WRITE_STMT (rdg, i)) | |
4785 | fprintf (file, "%d [style=filled, fillcolor=red]\n", i); | |
4786 | ||
4787 | if (v->succ) | |
4788 | for (e = v->succ; e; e = e->succ_next) | |
4789 | switch (RDGE_TYPE (e)) | |
4790 | { | |
4791 | case input_dd: | |
4792 | fprintf (file, "%d -> %d [label=input] \n", i, e->dest); | |
4793 | break; | |
4794 | ||
4795 | case output_dd: | |
4796 | fprintf (file, "%d -> %d [label=output] \n", i, e->dest); | |
4797 | break; | |
4798 | ||
4799 | case flow_dd: | |
4800 | /* These are the most common dependences: don't print these. */ | |
4801 | fprintf (file, "%d -> %d \n", i, e->dest); | |
4802 | break; | |
4803 | ||
4804 | case anti_dd: | |
4805 | fprintf (file, "%d -> %d [label=anti] \n", i, e->dest); | |
4806 | break; | |
4807 | ||
4808 | default: | |
4809 | gcc_unreachable (); | |
4810 | } | |
4811 | } | |
4812 | ||
4813 | fprintf (file, "}\n\n"); | |
4814 | } | |
4815 | ||
4816 | /* Display the Reduced Dependence Graph using dotty. */ | |
4817 | extern void dot_rdg (struct graph *); | |
4818 | ||
4819 | DEBUG_FUNCTION void | |
4820 | dot_rdg (struct graph *rdg) | |
4821 | { | |
4822 | /* When debugging, enable the following code. This cannot be used | |
4823 | in production compilers because it calls "system". */ | |
4824 | #if 0 | |
4825 | FILE *file = fopen ("/tmp/rdg.dot", "w"); | |
4826 | gcc_assert (file != NULL); | |
4827 | ||
4828 | dot_rdg_1 (file, rdg); | |
4829 | fclose (file); | |
4830 | ||
4831 | system ("dotty /tmp/rdg.dot &"); | |
4832 | #else | |
4833 | dot_rdg_1 (stderr, rdg); | |
4834 | #endif | |
4835 | } | |
4836 | ||
dea61d92 SP |
4837 | /* This structure is used for recording the mapping statement index in |
4838 | the RDG. */ | |
4839 | ||
d1b38208 | 4840 | struct GTY(()) rdg_vertex_info |
dea61d92 | 4841 | { |
726a989a | 4842 | gimple stmt; |
dea61d92 SP |
4843 | int index; |
4844 | }; | |
4845 | ||
4846 | /* Returns the index of STMT in RDG. */ | |
4847 | ||
4848 | int | |
726a989a | 4849 | rdg_vertex_for_stmt (struct graph *rdg, gimple stmt) |
dea61d92 SP |
4850 | { |
4851 | struct rdg_vertex_info rvi, *slot; | |
4852 | ||
4853 | rvi.stmt = stmt; | |
4854 | slot = (struct rdg_vertex_info *) htab_find (rdg->indices, &rvi); | |
4855 | ||
4856 | if (!slot) | |
4857 | return -1; | |
4858 | ||
4859 | return slot->index; | |
4860 | } | |
4861 | ||
4862 | /* Creates an edge in RDG for each distance vector from DDR. The | |
4863 | order that we keep track of in the RDG is the order in which | |
4864 | statements have to be executed. */ | |
4865 | ||
4866 | static void | |
4867 | create_rdg_edge_for_ddr (struct graph *rdg, ddr_p ddr) | |
4868 | { | |
4869 | struct graph_edge *e; | |
4870 | int va, vb; | |
4871 | data_reference_p dra = DDR_A (ddr); | |
4872 | data_reference_p drb = DDR_B (ddr); | |
4873 | unsigned level = ddr_dependence_level (ddr); | |
4874 | ||
4875 | /* For non scalar dependences, when the dependence is REVERSED, | |
4876 | statement B has to be executed before statement A. */ | |
4877 | if (level > 0 | |
4878 | && !DDR_REVERSED_P (ddr)) | |
3a796c6f | 4879 | { |
dea61d92 SP |
4880 | data_reference_p tmp = dra; |
4881 | dra = drb; | |
4882 | drb = tmp; | |
3a796c6f SP |
4883 | } |
4884 | ||
dea61d92 SP |
4885 | va = rdg_vertex_for_stmt (rdg, DR_STMT (dra)); |
4886 | vb = rdg_vertex_for_stmt (rdg, DR_STMT (drb)); | |
4887 | ||
4888 | if (va < 0 || vb < 0) | |
4889 | return; | |
3a796c6f SP |
4890 | |
4891 | e = add_edge (rdg, va, vb); | |
4892 | e->data = XNEW (struct rdg_edge); | |
4893 | ||
dea61d92 | 4894 | RDGE_LEVEL (e) = level; |
f8bf9252 | 4895 | RDGE_RELATION (e) = ddr; |
dea61d92 | 4896 | |
3a796c6f SP |
4897 | /* Determines the type of the data dependence. */ |
4898 | if (DR_IS_READ (dra) && DR_IS_READ (drb)) | |
4899 | RDGE_TYPE (e) = input_dd; | |
b0af49c4 | 4900 | else if (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)) |
3a796c6f | 4901 | RDGE_TYPE (e) = output_dd; |
b0af49c4 | 4902 | else if (DR_IS_WRITE (dra) && DR_IS_READ (drb)) |
3a796c6f | 4903 | RDGE_TYPE (e) = flow_dd; |
b0af49c4 | 4904 | else if (DR_IS_READ (dra) && DR_IS_WRITE (drb)) |
3a796c6f SP |
4905 | RDGE_TYPE (e) = anti_dd; |
4906 | } | |
4907 | ||
4908 | /* Creates dependence edges in RDG for all the uses of DEF. IDEF is | |
4909 | the index of DEF in RDG. */ | |
4910 | ||
4911 | static void | |
4912 | create_rdg_edges_for_scalar (struct graph *rdg, tree def, int idef) | |
4913 | { | |
4914 | use_operand_p imm_use_p; | |
4915 | imm_use_iterator iterator; | |
b8698a0f | 4916 | |
3a796c6f SP |
4917 | FOR_EACH_IMM_USE_FAST (imm_use_p, iterator, def) |
4918 | { | |
dea61d92 SP |
4919 | struct graph_edge *e; |
4920 | int use = rdg_vertex_for_stmt (rdg, USE_STMT (imm_use_p)); | |
3a796c6f | 4921 | |
dea61d92 SP |
4922 | if (use < 0) |
4923 | continue; | |
4924 | ||
4925 | e = add_edge (rdg, idef, use); | |
3a796c6f SP |
4926 | e->data = XNEW (struct rdg_edge); |
4927 | RDGE_TYPE (e) = flow_dd; | |
f8bf9252 | 4928 | RDGE_RELATION (e) = NULL; |
3a796c6f SP |
4929 | } |
4930 | } | |
4931 | ||
4932 | /* Creates the edges of the reduced dependence graph RDG. */ | |
4933 | ||
4934 | static void | |
4935 | create_rdg_edges (struct graph *rdg, VEC (ddr_p, heap) *ddrs) | |
4936 | { | |
4937 | int i; | |
4938 | struct data_dependence_relation *ddr; | |
4939 | def_operand_p def_p; | |
4940 | ssa_op_iter iter; | |
4941 | ||
ac47786e | 4942 | FOR_EACH_VEC_ELT (ddr_p, ddrs, i, ddr) |
3a796c6f SP |
4943 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
4944 | create_rdg_edge_for_ddr (rdg, ddr); | |
4945 | ||
4946 | for (i = 0; i < rdg->n_vertices; i++) | |
dea61d92 SP |
4947 | FOR_EACH_PHI_OR_STMT_DEF (def_p, RDG_STMT (rdg, i), |
4948 | iter, SSA_OP_DEF) | |
3a796c6f SP |
4949 | create_rdg_edges_for_scalar (rdg, DEF_FROM_PTR (def_p), i); |
4950 | } | |
4951 | ||
4952 | /* Build the vertices of the reduced dependence graph RDG. */ | |
4953 | ||
f8bf9252 | 4954 | void |
726a989a | 4955 | create_rdg_vertices (struct graph *rdg, VEC (gimple, heap) *stmts) |
3a796c6f | 4956 | { |
dea61d92 | 4957 | int i, j; |
726a989a | 4958 | gimple stmt; |
3a796c6f | 4959 | |
ac47786e | 4960 | FOR_EACH_VEC_ELT (gimple, stmts, i, stmt) |
3a796c6f | 4961 | { |
dea61d92 SP |
4962 | VEC (data_ref_loc, heap) *references; |
4963 | data_ref_loc *ref; | |
3a796c6f | 4964 | struct vertex *v = &(rdg->vertices[i]); |
dea61d92 SP |
4965 | struct rdg_vertex_info *rvi = XNEW (struct rdg_vertex_info); |
4966 | struct rdg_vertex_info **slot; | |
4967 | ||
4968 | rvi->stmt = stmt; | |
4969 | rvi->index = i; | |
4970 | slot = (struct rdg_vertex_info **) htab_find_slot (rdg->indices, rvi, INSERT); | |
4971 | ||
4972 | if (!*slot) | |
4973 | *slot = rvi; | |
4974 | else | |
4975 | free (rvi); | |
3a796c6f SP |
4976 | |
4977 | v->data = XNEW (struct rdg_vertex); | |
dea61d92 SP |
4978 | RDG_STMT (rdg, i) = stmt; |
4979 | ||
4980 | RDG_MEM_WRITE_STMT (rdg, i) = false; | |
4981 | RDG_MEM_READS_STMT (rdg, i) = false; | |
726a989a | 4982 | if (gimple_code (stmt) == GIMPLE_PHI) |
dea61d92 SP |
4983 | continue; |
4984 | ||
4985 | get_references_in_stmt (stmt, &references); | |
ac47786e | 4986 | FOR_EACH_VEC_ELT (data_ref_loc, references, j, ref) |
dea61d92 SP |
4987 | if (!ref->is_read) |
4988 | RDG_MEM_WRITE_STMT (rdg, i) = true; | |
4989 | else | |
4990 | RDG_MEM_READS_STMT (rdg, i) = true; | |
4991 | ||
4992 | VEC_free (data_ref_loc, heap, references); | |
3a796c6f SP |
4993 | } |
4994 | } | |
4995 | ||
dea61d92 SP |
4996 | /* Initialize STMTS with all the statements of LOOP. When |
4997 | INCLUDE_PHIS is true, include also the PHI nodes. The order in | |
4998 | which we discover statements is important as | |
4999 | generate_loops_for_partition is using the same traversal for | |
5000 | identifying statements. */ | |
3a796c6f SP |
5001 | |
5002 | static void | |
726a989a | 5003 | stmts_from_loop (struct loop *loop, VEC (gimple, heap) **stmts) |
3a796c6f SP |
5004 | { |
5005 | unsigned int i; | |
5006 | basic_block *bbs = get_loop_body_in_dom_order (loop); | |
5007 | ||
5008 | for (i = 0; i < loop->num_nodes; i++) | |
5009 | { | |
3a796c6f | 5010 | basic_block bb = bbs[i]; |
726a989a RB |
5011 | gimple_stmt_iterator bsi; |
5012 | gimple stmt; | |
3a796c6f | 5013 | |
726a989a RB |
5014 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
5015 | VEC_safe_push (gimple, heap, *stmts, gsi_stmt (bsi)); | |
3a796c6f | 5016 | |
726a989a RB |
5017 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
5018 | { | |
5019 | stmt = gsi_stmt (bsi); | |
5020 | if (gimple_code (stmt) != GIMPLE_LABEL) | |
5021 | VEC_safe_push (gimple, heap, *stmts, stmt); | |
5022 | } | |
3a796c6f SP |
5023 | } |
5024 | ||
5025 | free (bbs); | |
5026 | } | |
5027 | ||
5028 | /* Returns true when all the dependences are computable. */ | |
5029 | ||
5030 | static bool | |
5031 | known_dependences_p (VEC (ddr_p, heap) *dependence_relations) | |
5032 | { | |
5033 | ddr_p ddr; | |
5034 | unsigned int i; | |
5035 | ||
ac47786e | 5036 | FOR_EACH_VEC_ELT (ddr_p, dependence_relations, i, ddr) |
3a796c6f SP |
5037 | if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) |
5038 | return false; | |
b8698a0f | 5039 | |
3a796c6f SP |
5040 | return true; |
5041 | } | |
5042 | ||
dea61d92 SP |
5043 | /* Computes a hash function for element ELT. */ |
5044 | ||
5045 | static hashval_t | |
5046 | hash_stmt_vertex_info (const void *elt) | |
5047 | { | |
1634b18f KG |
5048 | const struct rdg_vertex_info *const rvi = |
5049 | (const struct rdg_vertex_info *) elt; | |
726a989a | 5050 | gimple stmt = rvi->stmt; |
dea61d92 SP |
5051 | |
5052 | return htab_hash_pointer (stmt); | |
5053 | } | |
5054 | ||
5055 | /* Compares database elements E1 and E2. */ | |
5056 | ||
5057 | static int | |
5058 | eq_stmt_vertex_info (const void *e1, const void *e2) | |
5059 | { | |
5060 | const struct rdg_vertex_info *elt1 = (const struct rdg_vertex_info *) e1; | |
5061 | const struct rdg_vertex_info *elt2 = (const struct rdg_vertex_info *) e2; | |
5062 | ||
5063 | return elt1->stmt == elt2->stmt; | |
5064 | } | |
5065 | ||
5066 | /* Free the element E. */ | |
5067 | ||
5068 | static void | |
5069 | hash_stmt_vertex_del (void *e) | |
5070 | { | |
5071 | free (e); | |
5072 | } | |
5073 | ||
f8bf9252 SP |
5074 | /* Build the Reduced Dependence Graph (RDG) with one vertex per |
5075 | statement of the loop nest, and one edge per data dependence or | |
5076 | scalar dependence. */ | |
5077 | ||
5078 | struct graph * | |
5079 | build_empty_rdg (int n_stmts) | |
5080 | { | |
5081 | int nb_data_refs = 10; | |
5082 | struct graph *rdg = new_graph (n_stmts); | |
5083 | ||
5084 | rdg->indices = htab_create (nb_data_refs, hash_stmt_vertex_info, | |
5085 | eq_stmt_vertex_info, hash_stmt_vertex_del); | |
5086 | return rdg; | |
5087 | } | |
5088 | ||
dea61d92 SP |
5089 | /* Build the Reduced Dependence Graph (RDG) with one vertex per |
5090 | statement of the loop nest, and one edge per data dependence or | |
5091 | scalar dependence. */ | |
3a796c6f SP |
5092 | |
5093 | struct graph * | |
01be8516 SP |
5094 | build_rdg (struct loop *loop, |
5095 | VEC (loop_p, heap) **loop_nest, | |
5096 | VEC (ddr_p, heap) **dependence_relations, | |
5097 | VEC (data_reference_p, heap) **datarefs) | |
3a796c6f | 5098 | { |
3a796c6f | 5099 | struct graph *rdg = NULL; |
01be8516 | 5100 | VEC (gimple, heap) *stmts = VEC_alloc (gimple, heap, 10); |
3a796c6f | 5101 | |
01be8516 SP |
5102 | compute_data_dependences_for_loop (loop, false, loop_nest, datarefs, |
5103 | dependence_relations); | |
dea61d92 | 5104 | |
01be8516 SP |
5105 | if (known_dependences_p (*dependence_relations)) |
5106 | { | |
5107 | stmts_from_loop (loop, &stmts); | |
5108 | rdg = build_empty_rdg (VEC_length (gimple, stmts)); | |
5109 | create_rdg_vertices (rdg, stmts); | |
5110 | create_rdg_edges (rdg, *dependence_relations); | |
5111 | } | |
3a796c6f | 5112 | |
726a989a | 5113 | VEC_free (gimple, heap, stmts); |
3a796c6f SP |
5114 | return rdg; |
5115 | } | |
dea61d92 SP |
5116 | |
5117 | /* Free the reduced dependence graph RDG. */ | |
5118 | ||
5119 | void | |
5120 | free_rdg (struct graph *rdg) | |
5121 | { | |
5122 | int i; | |
5123 | ||
5124 | for (i = 0; i < rdg->n_vertices; i++) | |
01be8516 SP |
5125 | { |
5126 | struct vertex *v = &(rdg->vertices[i]); | |
5127 | struct graph_edge *e; | |
5128 | ||
5129 | for (e = v->succ; e; e = e->succ_next) | |
04695783 | 5130 | free (e->data); |
01be8516 | 5131 | |
04695783 | 5132 | free (v->data); |
01be8516 | 5133 | } |
dea61d92 SP |
5134 | |
5135 | htab_delete (rdg->indices); | |
5136 | free_graph (rdg); | |
5137 | } | |
5138 | ||
5139 | /* Initialize STMTS with all the statements of LOOP that contain a | |
5140 | store to memory. */ | |
5141 | ||
5142 | void | |
726a989a | 5143 | stores_from_loop (struct loop *loop, VEC (gimple, heap) **stmts) |
dea61d92 SP |
5144 | { |
5145 | unsigned int i; | |
5146 | basic_block *bbs = get_loop_body_in_dom_order (loop); | |
5147 | ||
5148 | for (i = 0; i < loop->num_nodes; i++) | |
5149 | { | |
5150 | basic_block bb = bbs[i]; | |
726a989a | 5151 | gimple_stmt_iterator bsi; |
dea61d92 | 5152 | |
726a989a | 5153 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
5006671f | 5154 | if (gimple_vdef (gsi_stmt (bsi))) |
726a989a | 5155 | VEC_safe_push (gimple, heap, *stmts, gsi_stmt (bsi)); |
dea61d92 SP |
5156 | } |
5157 | ||
5158 | free (bbs); | |
5159 | } | |
5160 | ||
cfee318d SP |
5161 | /* Returns true when the statement at STMT is of the form "A[i] = 0" |
5162 | that contains a data reference on its LHS with a stride of the same | |
5163 | size as its unit type. */ | |
5e37ea0e | 5164 | |
cfee318d SP |
5165 | bool |
5166 | stmt_with_adjacent_zero_store_dr_p (gimple stmt) | |
5e37ea0e | 5167 | { |
cfee318d | 5168 | tree op0, op1; |
5e37ea0e | 5169 | bool res; |
cfee318d SP |
5170 | struct data_reference *dr; |
5171 | ||
5172 | if (!stmt | |
5173 | || !gimple_vdef (stmt) | |
5174 | || !is_gimple_assign (stmt) | |
5175 | || !gimple_assign_single_p (stmt) | |
5176 | || !(op1 = gimple_assign_rhs1 (stmt)) | |
5177 | || !(integer_zerop (op1) || real_zerop (op1))) | |
5178 | return false; | |
5179 | ||
5180 | dr = XCNEW (struct data_reference); | |
5181 | op0 = gimple_assign_lhs (stmt); | |
5e37ea0e SP |
5182 | |
5183 | DR_STMT (dr) = stmt; | |
5184 | DR_REF (dr) = op0; | |
5185 | ||
5186 | res = dr_analyze_innermost (dr) | |
5187 | && stride_of_unit_type_p (DR_STEP (dr), TREE_TYPE (op0)); | |
5188 | ||
5189 | free_data_ref (dr); | |
5190 | return res; | |
5191 | } | |
5192 | ||
20769d5e SP |
5193 | /* Initialize STMTS with all the statements of LOOP that contain a |
5194 | store to memory of the form "A[i] = 0". */ | |
5195 | ||
5196 | void | |
5197 | stores_zero_from_loop (struct loop *loop, VEC (gimple, heap) **stmts) | |
5198 | { | |
5199 | unsigned int i; | |
5200 | basic_block bb; | |
5201 | gimple_stmt_iterator si; | |
5202 | gimple stmt; | |
20769d5e SP |
5203 | basic_block *bbs = get_loop_body_in_dom_order (loop); |
5204 | ||
5205 | for (i = 0; i < loop->num_nodes; i++) | |
5206 | for (bb = bbs[i], si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) | |
5207 | if ((stmt = gsi_stmt (si)) | |
cfee318d | 5208 | && stmt_with_adjacent_zero_store_dr_p (stmt)) |
20769d5e SP |
5209 | VEC_safe_push (gimple, heap, *stmts, gsi_stmt (si)); |
5210 | ||
5211 | free (bbs); | |
5212 | } | |
5213 | ||
dea61d92 SP |
5214 | /* For a data reference REF, return the declaration of its base |
5215 | address or NULL_TREE if the base is not determined. */ | |
5216 | ||
5217 | static inline tree | |
726a989a | 5218 | ref_base_address (gimple stmt, data_ref_loc *ref) |
dea61d92 SP |
5219 | { |
5220 | tree base = NULL_TREE; | |
5221 | tree base_address; | |
5222 | struct data_reference *dr = XCNEW (struct data_reference); | |
5223 | ||
5224 | DR_STMT (dr) = stmt; | |
5225 | DR_REF (dr) = *ref->pos; | |
5226 | dr_analyze_innermost (dr); | |
5227 | base_address = DR_BASE_ADDRESS (dr); | |
5228 | ||
5229 | if (!base_address) | |
5230 | goto end; | |
5231 | ||
5232 | switch (TREE_CODE (base_address)) | |
5233 | { | |
5234 | case ADDR_EXPR: | |
5235 | base = TREE_OPERAND (base_address, 0); | |
5236 | break; | |
5237 | ||
5238 | default: | |
5239 | base = base_address; | |
5240 | break; | |
5241 | } | |
5242 | ||
5243 | end: | |
5244 | free_data_ref (dr); | |
5245 | return base; | |
5246 | } | |
5247 | ||
5248 | /* Determines whether the statement from vertex V of the RDG has a | |
5249 | definition used outside the loop that contains this statement. */ | |
5250 | ||
5251 | bool | |
5252 | rdg_defs_used_in_other_loops_p (struct graph *rdg, int v) | |
5253 | { | |
726a989a | 5254 | gimple stmt = RDG_STMT (rdg, v); |
dea61d92 SP |
5255 | struct loop *loop = loop_containing_stmt (stmt); |
5256 | use_operand_p imm_use_p; | |
5257 | imm_use_iterator iterator; | |
5258 | ssa_op_iter it; | |
5259 | def_operand_p def_p; | |
5260 | ||
5261 | if (!loop) | |
5262 | return true; | |
5263 | ||
5264 | FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, it, SSA_OP_DEF) | |
5265 | { | |
5266 | FOR_EACH_IMM_USE_FAST (imm_use_p, iterator, DEF_FROM_PTR (def_p)) | |
5267 | { | |
5268 | if (loop_containing_stmt (USE_STMT (imm_use_p)) != loop) | |
5269 | return true; | |
5270 | } | |
5271 | } | |
5272 | ||
5273 | return false; | |
5274 | } | |
5275 | ||
5276 | /* Determines whether statements S1 and S2 access to similar memory | |
5277 | locations. Two memory accesses are considered similar when they | |
5278 | have the same base address declaration, i.e. when their | |
5279 | ref_base_address is the same. */ | |
5280 | ||
5281 | bool | |
726a989a | 5282 | have_similar_memory_accesses (gimple s1, gimple s2) |
dea61d92 SP |
5283 | { |
5284 | bool res = false; | |
5285 | unsigned i, j; | |
5286 | VEC (data_ref_loc, heap) *refs1, *refs2; | |
5287 | data_ref_loc *ref1, *ref2; | |
5288 | ||
5289 | get_references_in_stmt (s1, &refs1); | |
5290 | get_references_in_stmt (s2, &refs2); | |
5291 | ||
ac47786e | 5292 | FOR_EACH_VEC_ELT (data_ref_loc, refs1, i, ref1) |
dea61d92 SP |
5293 | { |
5294 | tree base1 = ref_base_address (s1, ref1); | |
5295 | ||
5296 | if (base1) | |
ac47786e | 5297 | FOR_EACH_VEC_ELT (data_ref_loc, refs2, j, ref2) |
dea61d92 SP |
5298 | if (base1 == ref_base_address (s2, ref2)) |
5299 | { | |
5300 | res = true; | |
5301 | goto end; | |
5302 | } | |
5303 | } | |
5304 | ||
5305 | end: | |
5306 | VEC_free (data_ref_loc, heap, refs1); | |
5307 | VEC_free (data_ref_loc, heap, refs2); | |
5308 | return res; | |
5309 | } | |
5310 | ||
5311 | /* Helper function for the hashtab. */ | |
5312 | ||
5313 | static int | |
5314 | have_similar_memory_accesses_1 (const void *s1, const void *s2) | |
5315 | { | |
726a989a RB |
5316 | return have_similar_memory_accesses (CONST_CAST_GIMPLE ((const_gimple) s1), |
5317 | CONST_CAST_GIMPLE ((const_gimple) s2)); | |
dea61d92 SP |
5318 | } |
5319 | ||
5320 | /* Helper function for the hashtab. */ | |
5321 | ||
5322 | static hashval_t | |
5323 | ref_base_address_1 (const void *s) | |
5324 | { | |
726a989a | 5325 | gimple stmt = CONST_CAST_GIMPLE ((const_gimple) s); |
dea61d92 SP |
5326 | unsigned i; |
5327 | VEC (data_ref_loc, heap) *refs; | |
5328 | data_ref_loc *ref; | |
5329 | hashval_t res = 0; | |
5330 | ||
5331 | get_references_in_stmt (stmt, &refs); | |
5332 | ||
ac47786e | 5333 | FOR_EACH_VEC_ELT (data_ref_loc, refs, i, ref) |
dea61d92 SP |
5334 | if (!ref->is_read) |
5335 | { | |
5336 | res = htab_hash_pointer (ref_base_address (stmt, ref)); | |
5337 | break; | |
5338 | } | |
5339 | ||
5340 | VEC_free (data_ref_loc, heap, refs); | |
5341 | return res; | |
5342 | } | |
5343 | ||
5344 | /* Try to remove duplicated write data references from STMTS. */ | |
5345 | ||
5346 | void | |
726a989a | 5347 | remove_similar_memory_refs (VEC (gimple, heap) **stmts) |
dea61d92 SP |
5348 | { |
5349 | unsigned i; | |
726a989a RB |
5350 | gimple stmt; |
5351 | htab_t seen = htab_create (VEC_length (gimple, *stmts), ref_base_address_1, | |
dea61d92 SP |
5352 | have_similar_memory_accesses_1, NULL); |
5353 | ||
726a989a | 5354 | for (i = 0; VEC_iterate (gimple, *stmts, i, stmt); ) |
dea61d92 SP |
5355 | { |
5356 | void **slot; | |
5357 | ||
5358 | slot = htab_find_slot (seen, stmt, INSERT); | |
5359 | ||
5360 | if (*slot) | |
726a989a | 5361 | VEC_ordered_remove (gimple, *stmts, i); |
dea61d92 SP |
5362 | else |
5363 | { | |
5364 | *slot = (void *) stmt; | |
5365 | i++; | |
5366 | } | |
5367 | } | |
5368 | ||
5369 | htab_delete (seen); | |
5370 | } | |
5371 | ||
9f275479 JS |
5372 | /* Returns the index of PARAMETER in the parameters vector of the |
5373 | ACCESS_MATRIX. If PARAMETER does not exist return -1. */ | |
5374 | ||
b8698a0f L |
5375 | int |
5376 | access_matrix_get_index_for_parameter (tree parameter, | |
9f275479 JS |
5377 | struct access_matrix *access_matrix) |
5378 | { | |
5379 | int i; | |
5380 | VEC (tree,heap) *lambda_parameters = AM_PARAMETERS (access_matrix); | |
5381 | tree lambda_parameter; | |
5382 | ||
ac47786e | 5383 | FOR_EACH_VEC_ELT (tree, lambda_parameters, i, lambda_parameter) |
9f275479 JS |
5384 | if (lambda_parameter == parameter) |
5385 | return i + AM_NB_INDUCTION_VARS (access_matrix); | |
5386 | ||
5387 | return -1; | |
5388 | } |