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56cf8686 | 1 | /* Data references and dependences detectors. |
23a5b65a | 2 | Copyright (C) 2003-2014 Free Software Foundation, Inc. |
0ff4040e | 3 | Contributed by Sebastian Pop <pop@cri.ensmp.fr> |
56cf8686 SP |
4 | |
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 9 | Software Foundation; either version 3, or (at your option) any later |
56cf8686 SP |
10 | version. |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
56cf8686 SP |
20 | |
21 | /* This pass walks a given loop structure searching for array | |
22 | references. The information about the array accesses is recorded | |
b8698a0f L |
23 | in DATA_REFERENCE structures. |
24 | ||
25 | The basic test for determining the dependences is: | |
26 | given two access functions chrec1 and chrec2 to a same array, and | |
27 | x and y two vectors from the iteration domain, the same element of | |
56cf8686 SP |
28 | the array is accessed twice at iterations x and y if and only if: |
29 | | chrec1 (x) == chrec2 (y). | |
b8698a0f | 30 | |
56cf8686 | 31 | The goals of this analysis are: |
b8698a0f | 32 | |
56cf8686 SP |
33 | - to determine the independence: the relation between two |
34 | independent accesses is qualified with the chrec_known (this | |
35 | information allows a loop parallelization), | |
b8698a0f | 36 | |
56cf8686 SP |
37 | - when two data references access the same data, to qualify the |
38 | dependence relation with classic dependence representations: | |
b8698a0f | 39 | |
56cf8686 SP |
40 | - distance vectors |
41 | - direction vectors | |
42 | - loop carried level dependence | |
43 | - polyhedron dependence | |
44 | or with the chains of recurrences based representation, | |
b8698a0f L |
45 | |
46 | - to define a knowledge base for storing the data dependence | |
56cf8686 | 47 | information, |
b8698a0f | 48 | |
56cf8686 | 49 | - to define an interface to access this data. |
b8698a0f L |
50 | |
51 | ||
56cf8686 | 52 | Definitions: |
b8698a0f | 53 | |
56cf8686 SP |
54 | - subscript: given two array accesses a subscript is the tuple |
55 | composed of the access functions for a given dimension. Example: | |
56 | Given A[f1][f2][f3] and B[g1][g2][g3], there are three subscripts: | |
57 | (f1, g1), (f2, g2), (f3, g3). | |
58 | ||
59 | - Diophantine equation: an equation whose coefficients and | |
b8698a0f | 60 | solutions are integer constants, for example the equation |
56cf8686 SP |
61 | | 3*x + 2*y = 1 |
62 | has an integer solution x = 1 and y = -1. | |
b8698a0f | 63 | |
56cf8686 | 64 | References: |
b8698a0f | 65 | |
56cf8686 SP |
66 | - "Advanced Compilation for High Performance Computing" by Randy |
67 | Allen and Ken Kennedy. | |
b8698a0f L |
68 | http://citeseer.ist.psu.edu/goff91practical.html |
69 | ||
70 | - "Loop Transformations for Restructuring Compilers - The Foundations" | |
56cf8686 SP |
71 | by Utpal Banerjee. |
72 | ||
b8698a0f | 73 | |
56cf8686 SP |
74 | */ |
75 | ||
76 | #include "config.h" | |
77 | #include "system.h" | |
78 | #include "coretypes.h" | |
cf2d1b38 | 79 | #include "tree.h" |
d8a2d370 | 80 | #include "expr.h" |
cf835838 | 81 | #include "gimple-pretty-print.h" |
60393bbc AM |
82 | #include "predict.h" |
83 | #include "vec.h" | |
84 | #include "hashtab.h" | |
85 | #include "hash-set.h" | |
86 | #include "machmode.h" | |
87 | #include "tm.h" | |
88 | #include "hard-reg-set.h" | |
89 | #include "input.h" | |
90 | #include "function.h" | |
91 | #include "dominance.h" | |
92 | #include "cfg.h" | |
2fb9a547 AM |
93 | #include "basic-block.h" |
94 | #include "tree-ssa-alias.h" | |
95 | #include "internal-fn.h" | |
96 | #include "gimple-expr.h" | |
97 | #include "is-a.h" | |
442b4905 | 98 | #include "gimple.h" |
5be5c238 | 99 | #include "gimple-iterator.h" |
e28030cf | 100 | #include "tree-ssa-loop-niter.h" |
442b4905 | 101 | #include "tree-ssa-loop.h" |
7a300452 | 102 | #include "tree-ssa.h" |
56cf8686 | 103 | #include "cfgloop.h" |
56cf8686 SP |
104 | #include "tree-data-ref.h" |
105 | #include "tree-scalar-evolution.h" | |
7ee2468b | 106 | #include "dumpfile.h" |
946e1bc7 | 107 | #include "langhooks.h" |
02f5d6c5 | 108 | #include "tree-affine.h" |
3881dee9 | 109 | #include "params.h" |
56cf8686 | 110 | |
0ff4040e SP |
111 | static struct datadep_stats |
112 | { | |
113 | int num_dependence_tests; | |
114 | int num_dependence_dependent; | |
115 | int num_dependence_independent; | |
116 | int num_dependence_undetermined; | |
117 | ||
118 | int num_subscript_tests; | |
119 | int num_subscript_undetermined; | |
120 | int num_same_subscript_function; | |
121 | ||
122 | int num_ziv; | |
123 | int num_ziv_independent; | |
124 | int num_ziv_dependent; | |
125 | int num_ziv_unimplemented; | |
126 | ||
127 | int num_siv; | |
128 | int num_siv_independent; | |
129 | int num_siv_dependent; | |
130 | int num_siv_unimplemented; | |
131 | ||
132 | int num_miv; | |
133 | int num_miv_independent; | |
134 | int num_miv_dependent; | |
135 | int num_miv_unimplemented; | |
136 | } dependence_stats; | |
137 | ||
ba42e045 SP |
138 | static bool subscript_dependence_tester_1 (struct data_dependence_relation *, |
139 | struct data_reference *, | |
da9a21f4 SP |
140 | struct data_reference *, |
141 | struct loop *); | |
56cf8686 SP |
142 | /* Returns true iff A divides B. */ |
143 | ||
b8698a0f | 144 | static inline bool |
ed7a4b4b | 145 | tree_fold_divides_p (const_tree a, const_tree b) |
56cf8686 | 146 | { |
b73a6056 RS |
147 | gcc_assert (TREE_CODE (a) == INTEGER_CST); |
148 | gcc_assert (TREE_CODE (b) == INTEGER_CST); | |
d35936ab | 149 | return integer_zerop (int_const_binop (TRUNC_MOD_EXPR, b, a)); |
56cf8686 SP |
150 | } |
151 | ||
86df10e3 SP |
152 | /* Returns true iff A divides B. */ |
153 | ||
b8698a0f | 154 | static inline bool |
86df10e3 SP |
155 | int_divides_p (int a, int b) |
156 | { | |
157 | return ((b % a) == 0); | |
56cf8686 SP |
158 | } |
159 | ||
160 | \f | |
161 | ||
b8698a0f | 162 | /* Dump into FILE all the data references from DATAREFS. */ |
56cf8686 | 163 | |
aeb83f09 | 164 | static void |
9771b263 | 165 | dump_data_references (FILE *file, vec<data_reference_p> datarefs) |
56cf8686 SP |
166 | { |
167 | unsigned int i; | |
ebf78a47 SP |
168 | struct data_reference *dr; |
169 | ||
9771b263 | 170 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
ebf78a47 | 171 | dump_data_reference (file, dr); |
56cf8686 SP |
172 | } |
173 | ||
7b3b6ae4 LC |
174 | /* Unified dump into FILE all the data references from DATAREFS. */ |
175 | ||
176 | DEBUG_FUNCTION void | |
177 | debug (vec<data_reference_p> &ref) | |
178 | { | |
179 | dump_data_references (stderr, ref); | |
180 | } | |
181 | ||
182 | DEBUG_FUNCTION void | |
183 | debug (vec<data_reference_p> *ptr) | |
184 | { | |
185 | if (ptr) | |
186 | debug (*ptr); | |
187 | else | |
188 | fprintf (stderr, "<nil>\n"); | |
189 | } | |
190 | ||
191 | ||
b8698a0f | 192 | /* Dump into STDERR all the data references from DATAREFS. */ |
a37d995a | 193 | |
24e47c76 | 194 | DEBUG_FUNCTION void |
9771b263 | 195 | debug_data_references (vec<data_reference_p> datarefs) |
a37d995a SP |
196 | { |
197 | dump_data_references (stderr, datarefs); | |
198 | } | |
199 | ||
a37d995a SP |
200 | /* Print to STDERR the data_reference DR. */ |
201 | ||
24e47c76 | 202 | DEBUG_FUNCTION void |
a37d995a SP |
203 | debug_data_reference (struct data_reference *dr) |
204 | { | |
205 | dump_data_reference (stderr, dr); | |
206 | } | |
207 | ||
56cf8686 SP |
208 | /* Dump function for a DATA_REFERENCE structure. */ |
209 | ||
b8698a0f L |
210 | void |
211 | dump_data_reference (FILE *outf, | |
56cf8686 SP |
212 | struct data_reference *dr) |
213 | { | |
214 | unsigned int i; | |
b8698a0f | 215 | |
28c5db57 SP |
216 | fprintf (outf, "#(Data Ref: \n"); |
217 | fprintf (outf, "# bb: %d \n", gimple_bb (DR_STMT (dr))->index); | |
218 | fprintf (outf, "# stmt: "); | |
726a989a | 219 | print_gimple_stmt (outf, DR_STMT (dr), 0, 0); |
03922af3 | 220 | fprintf (outf, "# ref: "); |
56cf8686 | 221 | print_generic_stmt (outf, DR_REF (dr), 0); |
03922af3 | 222 | fprintf (outf, "# base_object: "); |
86a07404 | 223 | print_generic_stmt (outf, DR_BASE_OBJECT (dr), 0); |
b8698a0f | 224 | |
56cf8686 SP |
225 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
226 | { | |
03922af3 | 227 | fprintf (outf, "# Access function %d: ", i); |
56cf8686 SP |
228 | print_generic_stmt (outf, DR_ACCESS_FN (dr, i), 0); |
229 | } | |
03922af3 | 230 | fprintf (outf, "#)\n"); |
56cf8686 SP |
231 | } |
232 | ||
7b3b6ae4 LC |
233 | /* Unified dump function for a DATA_REFERENCE structure. */ |
234 | ||
235 | DEBUG_FUNCTION void | |
236 | debug (data_reference &ref) | |
237 | { | |
238 | dump_data_reference (stderr, &ref); | |
239 | } | |
240 | ||
241 | DEBUG_FUNCTION void | |
242 | debug (data_reference *ptr) | |
243 | { | |
244 | if (ptr) | |
245 | debug (*ptr); | |
246 | else | |
247 | fprintf (stderr, "<nil>\n"); | |
248 | } | |
249 | ||
250 | ||
d93817c4 ZD |
251 | /* Dumps the affine function described by FN to the file OUTF. */ |
252 | ||
253 | static void | |
254 | dump_affine_function (FILE *outf, affine_fn fn) | |
255 | { | |
256 | unsigned i; | |
257 | tree coef; | |
258 | ||
9771b263 DN |
259 | print_generic_expr (outf, fn[0], TDF_SLIM); |
260 | for (i = 1; fn.iterate (i, &coef); i++) | |
d93817c4 ZD |
261 | { |
262 | fprintf (outf, " + "); | |
263 | print_generic_expr (outf, coef, TDF_SLIM); | |
264 | fprintf (outf, " * x_%u", i); | |
265 | } | |
266 | } | |
267 | ||
268 | /* Dumps the conflict function CF to the file OUTF. */ | |
269 | ||
270 | static void | |
271 | dump_conflict_function (FILE *outf, conflict_function *cf) | |
272 | { | |
273 | unsigned i; | |
274 | ||
275 | if (cf->n == NO_DEPENDENCE) | |
bcf1ef00 | 276 | fprintf (outf, "no dependence"); |
d93817c4 | 277 | else if (cf->n == NOT_KNOWN) |
bcf1ef00 | 278 | fprintf (outf, "not known"); |
d93817c4 ZD |
279 | else |
280 | { | |
281 | for (i = 0; i < cf->n; i++) | |
282 | { | |
bcf1ef00 RB |
283 | if (i != 0) |
284 | fprintf (outf, " "); | |
d93817c4 ZD |
285 | fprintf (outf, "["); |
286 | dump_affine_function (outf, cf->fns[i]); | |
bcf1ef00 | 287 | fprintf (outf, "]"); |
d93817c4 ZD |
288 | } |
289 | } | |
290 | } | |
291 | ||
86df10e3 SP |
292 | /* Dump function for a SUBSCRIPT structure. */ |
293 | ||
aeb83f09 | 294 | static void |
86df10e3 SP |
295 | dump_subscript (FILE *outf, struct subscript *subscript) |
296 | { | |
d93817c4 | 297 | conflict_function *cf = SUB_CONFLICTS_IN_A (subscript); |
86df10e3 SP |
298 | |
299 | fprintf (outf, "\n (subscript \n"); | |
300 | fprintf (outf, " iterations_that_access_an_element_twice_in_A: "); | |
d93817c4 ZD |
301 | dump_conflict_function (outf, cf); |
302 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
303 | { |
304 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
bcf1ef00 RB |
305 | fprintf (outf, "\n last_conflict: "); |
306 | print_generic_expr (outf, last_iteration, 0); | |
86df10e3 | 307 | } |
b8698a0f | 308 | |
d93817c4 | 309 | cf = SUB_CONFLICTS_IN_B (subscript); |
bcf1ef00 | 310 | fprintf (outf, "\n iterations_that_access_an_element_twice_in_B: "); |
d93817c4 ZD |
311 | dump_conflict_function (outf, cf); |
312 | if (CF_NONTRIVIAL_P (cf)) | |
86df10e3 SP |
313 | { |
314 | tree last_iteration = SUB_LAST_CONFLICT (subscript); | |
bcf1ef00 RB |
315 | fprintf (outf, "\n last_conflict: "); |
316 | print_generic_expr (outf, last_iteration, 0); | |
86df10e3 SP |
317 | } |
318 | ||
bcf1ef00 RB |
319 | fprintf (outf, "\n (Subscript distance: "); |
320 | print_generic_expr (outf, SUB_DISTANCE (subscript), 0); | |
321 | fprintf (outf, " ))\n"); | |
86df10e3 SP |
322 | } |
323 | ||
0ff4040e SP |
324 | /* Print the classic direction vector DIRV to OUTF. */ |
325 | ||
aeb83f09 | 326 | static void |
0ff4040e SP |
327 | print_direction_vector (FILE *outf, |
328 | lambda_vector dirv, | |
329 | int length) | |
330 | { | |
331 | int eq; | |
332 | ||
333 | for (eq = 0; eq < length; eq++) | |
334 | { | |
81f40b79 ILT |
335 | enum data_dependence_direction dir = ((enum data_dependence_direction) |
336 | dirv[eq]); | |
0ff4040e SP |
337 | |
338 | switch (dir) | |
339 | { | |
340 | case dir_positive: | |
341 | fprintf (outf, " +"); | |
342 | break; | |
343 | case dir_negative: | |
344 | fprintf (outf, " -"); | |
345 | break; | |
346 | case dir_equal: | |
347 | fprintf (outf, " ="); | |
348 | break; | |
349 | case dir_positive_or_equal: | |
350 | fprintf (outf, " +="); | |
351 | break; | |
352 | case dir_positive_or_negative: | |
353 | fprintf (outf, " +-"); | |
354 | break; | |
355 | case dir_negative_or_equal: | |
356 | fprintf (outf, " -="); | |
357 | break; | |
358 | case dir_star: | |
359 | fprintf (outf, " *"); | |
360 | break; | |
361 | default: | |
362 | fprintf (outf, "indep"); | |
363 | break; | |
364 | } | |
365 | } | |
366 | fprintf (outf, "\n"); | |
367 | } | |
368 | ||
ba42e045 SP |
369 | /* Print a vector of direction vectors. */ |
370 | ||
aeb83f09 | 371 | static void |
9771b263 | 372 | print_dir_vectors (FILE *outf, vec<lambda_vector> dir_vects, |
ba42e045 SP |
373 | int length) |
374 | { | |
375 | unsigned j; | |
376 | lambda_vector v; | |
377 | ||
9771b263 | 378 | FOR_EACH_VEC_ELT (dir_vects, j, v) |
ba42e045 SP |
379 | print_direction_vector (outf, v, length); |
380 | } | |
381 | ||
b305e3da SP |
382 | /* Print out a vector VEC of length N to OUTFILE. */ |
383 | ||
384 | static inline void | |
385 | print_lambda_vector (FILE * outfile, lambda_vector vector, int n) | |
386 | { | |
387 | int i; | |
388 | ||
389 | for (i = 0; i < n; i++) | |
390 | fprintf (outfile, "%3d ", vector[i]); | |
391 | fprintf (outfile, "\n"); | |
392 | } | |
393 | ||
ba42e045 SP |
394 | /* Print a vector of distance vectors. */ |
395 | ||
aeb83f09 | 396 | static void |
9771b263 | 397 | print_dist_vectors (FILE *outf, vec<lambda_vector> dist_vects, |
aeb83f09 | 398 | int length) |
ba42e045 SP |
399 | { |
400 | unsigned j; | |
401 | lambda_vector v; | |
402 | ||
9771b263 | 403 | FOR_EACH_VEC_ELT (dist_vects, j, v) |
ba42e045 SP |
404 | print_lambda_vector (outf, v, length); |
405 | } | |
406 | ||
56cf8686 SP |
407 | /* Dump function for a DATA_DEPENDENCE_RELATION structure. */ |
408 | ||
aeb83f09 | 409 | static void |
b8698a0f | 410 | dump_data_dependence_relation (FILE *outf, |
56cf8686 SP |
411 | struct data_dependence_relation *ddr) |
412 | { | |
56cf8686 | 413 | struct data_reference *dra, *drb; |
86df10e3 | 414 | |
86df10e3 | 415 | fprintf (outf, "(Data Dep: \n"); |
dea61d92 | 416 | |
ed2024ba MJ |
417 | if (!ddr || DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) |
418 | { | |
b61b1f17 MM |
419 | if (ddr) |
420 | { | |
421 | dra = DDR_A (ddr); | |
422 | drb = DDR_B (ddr); | |
423 | if (dra) | |
424 | dump_data_reference (outf, dra); | |
425 | else | |
426 | fprintf (outf, " (nil)\n"); | |
427 | if (drb) | |
428 | dump_data_reference (outf, drb); | |
429 | else | |
430 | fprintf (outf, " (nil)\n"); | |
431 | } | |
ed2024ba MJ |
432 | fprintf (outf, " (don't know)\n)\n"); |
433 | return; | |
434 | } | |
435 | ||
436 | dra = DDR_A (ddr); | |
437 | drb = DDR_B (ddr); | |
dea61d92 SP |
438 | dump_data_reference (outf, dra); |
439 | dump_data_reference (outf, drb); | |
440 | ||
ed2024ba | 441 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
56cf8686 | 442 | fprintf (outf, " (no dependence)\n"); |
b8698a0f | 443 | |
86df10e3 | 444 | else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
56cf8686 | 445 | { |
86df10e3 | 446 | unsigned int i; |
ba42e045 | 447 | struct loop *loopi; |
304afda6 | 448 | |
56cf8686 SP |
449 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
450 | { | |
56cf8686 SP |
451 | fprintf (outf, " access_fn_A: "); |
452 | print_generic_stmt (outf, DR_ACCESS_FN (dra, i), 0); | |
453 | fprintf (outf, " access_fn_B: "); | |
454 | print_generic_stmt (outf, DR_ACCESS_FN (drb, i), 0); | |
86df10e3 | 455 | dump_subscript (outf, DDR_SUBSCRIPT (ddr, i)); |
56cf8686 | 456 | } |
304afda6 | 457 | |
3d8864c0 | 458 | fprintf (outf, " inner loop index: %d\n", DDR_INNER_LOOP (ddr)); |
ba42e045 | 459 | fprintf (outf, " loop nest: ("); |
9771b263 | 460 | FOR_EACH_VEC_ELT (DDR_LOOP_NEST (ddr), i, loopi) |
ba42e045 SP |
461 | fprintf (outf, "%d ", loopi->num); |
462 | fprintf (outf, ")\n"); | |
463 | ||
304afda6 | 464 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) |
56cf8686 | 465 | { |
304afda6 SP |
466 | fprintf (outf, " distance_vector: "); |
467 | print_lambda_vector (outf, DDR_DIST_VECT (ddr, i), | |
ba42e045 | 468 | DDR_NB_LOOPS (ddr)); |
86df10e3 | 469 | } |
304afda6 SP |
470 | |
471 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
86df10e3 | 472 | { |
304afda6 | 473 | fprintf (outf, " direction_vector: "); |
0ff4040e | 474 | print_direction_vector (outf, DDR_DIR_VECT (ddr, i), |
ba42e045 | 475 | DDR_NB_LOOPS (ddr)); |
56cf8686 | 476 | } |
56cf8686 SP |
477 | } |
478 | ||
479 | fprintf (outf, ")\n"); | |
480 | } | |
481 | ||
aeb83f09 | 482 | /* Debug version. */ |
56cf8686 | 483 | |
aeb83f09 RG |
484 | DEBUG_FUNCTION void |
485 | debug_data_dependence_relation (struct data_dependence_relation *ddr) | |
56cf8686 | 486 | { |
aeb83f09 RG |
487 | dump_data_dependence_relation (stderr, ddr); |
488 | } | |
b8698a0f | 489 | |
aeb83f09 | 490 | /* Dump into FILE all the dependence relations from DDRS. */ |
b8698a0f | 491 | |
aeb83f09 RG |
492 | void |
493 | dump_data_dependence_relations (FILE *file, | |
9771b263 | 494 | vec<ddr_p> ddrs) |
aeb83f09 RG |
495 | { |
496 | unsigned int i; | |
497 | struct data_dependence_relation *ddr; | |
b8698a0f | 498 | |
9771b263 | 499 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
aeb83f09 RG |
500 | dump_data_dependence_relation (file, ddr); |
501 | } | |
b8698a0f | 502 | |
7b3b6ae4 LC |
503 | DEBUG_FUNCTION void |
504 | debug (vec<ddr_p> &ref) | |
505 | { | |
506 | dump_data_dependence_relations (stderr, ref); | |
507 | } | |
508 | ||
509 | DEBUG_FUNCTION void | |
510 | debug (vec<ddr_p> *ptr) | |
511 | { | |
512 | if (ptr) | |
513 | debug (*ptr); | |
514 | else | |
515 | fprintf (stderr, "<nil>\n"); | |
516 | } | |
517 | ||
518 | ||
aeb83f09 | 519 | /* Dump to STDERR all the dependence relations from DDRS. */ |
b8698a0f | 520 | |
aeb83f09 | 521 | DEBUG_FUNCTION void |
9771b263 | 522 | debug_data_dependence_relations (vec<ddr_p> ddrs) |
aeb83f09 RG |
523 | { |
524 | dump_data_dependence_relations (stderr, ddrs); | |
56cf8686 SP |
525 | } |
526 | ||
86df10e3 SP |
527 | /* Dumps the distance and direction vectors in FILE. DDRS contains |
528 | the dependence relations, and VECT_SIZE is the size of the | |
529 | dependence vectors, or in other words the number of loops in the | |
530 | considered nest. */ | |
531 | ||
aeb83f09 | 532 | static void |
9771b263 | 533 | dump_dist_dir_vectors (FILE *file, vec<ddr_p> ddrs) |
86df10e3 | 534 | { |
304afda6 | 535 | unsigned int i, j; |
ebf78a47 SP |
536 | struct data_dependence_relation *ddr; |
537 | lambda_vector v; | |
86df10e3 | 538 | |
9771b263 | 539 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
ebf78a47 SP |
540 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_AFFINE_P (ddr)) |
541 | { | |
9771b263 | 542 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), j, v) |
ebf78a47 SP |
543 | { |
544 | fprintf (file, "DISTANCE_V ("); | |
545 | print_lambda_vector (file, v, DDR_NB_LOOPS (ddr)); | |
546 | fprintf (file, ")\n"); | |
547 | } | |
548 | ||
9771b263 | 549 | FOR_EACH_VEC_ELT (DDR_DIR_VECTS (ddr), j, v) |
ebf78a47 SP |
550 | { |
551 | fprintf (file, "DIRECTION_V ("); | |
552 | print_direction_vector (file, v, DDR_NB_LOOPS (ddr)); | |
553 | fprintf (file, ")\n"); | |
554 | } | |
555 | } | |
304afda6 | 556 | |
86df10e3 SP |
557 | fprintf (file, "\n\n"); |
558 | } | |
559 | ||
560 | /* Dumps the data dependence relations DDRS in FILE. */ | |
561 | ||
aeb83f09 | 562 | static void |
9771b263 | 563 | dump_ddrs (FILE *file, vec<ddr_p> ddrs) |
86df10e3 SP |
564 | { |
565 | unsigned int i; | |
ebf78a47 SP |
566 | struct data_dependence_relation *ddr; |
567 | ||
9771b263 | 568 | FOR_EACH_VEC_ELT (ddrs, i, ddr) |
ebf78a47 | 569 | dump_data_dependence_relation (file, ddr); |
86df10e3 | 570 | |
86df10e3 SP |
571 | fprintf (file, "\n\n"); |
572 | } | |
573 | ||
aeb83f09 | 574 | DEBUG_FUNCTION void |
9771b263 | 575 | debug_ddrs (vec<ddr_p> ddrs) |
aeb83f09 RG |
576 | { |
577 | dump_ddrs (stderr, ddrs); | |
578 | } | |
579 | ||
726a989a RB |
580 | /* Helper function for split_constant_offset. Expresses OP0 CODE OP1 |
581 | (the type of the result is TYPE) as VAR + OFF, where OFF is a nonzero | |
582 | constant of type ssizetype, and returns true. If we cannot do this | |
583 | with OFF nonzero, OFF and VAR are set to NULL_TREE instead and false | |
584 | is returned. */ | |
86a07404 | 585 | |
726a989a RB |
586 | static bool |
587 | split_constant_offset_1 (tree type, tree op0, enum tree_code code, tree op1, | |
588 | tree *var, tree *off) | |
86a07404 | 589 | { |
3cb960c7 ZD |
590 | tree var0, var1; |
591 | tree off0, off1; | |
726a989a | 592 | enum tree_code ocode = code; |
86a07404 | 593 | |
726a989a RB |
594 | *var = NULL_TREE; |
595 | *off = NULL_TREE; | |
86a07404 | 596 | |
5be014d5 | 597 | switch (code) |
86a07404 | 598 | { |
3cb960c7 ZD |
599 | case INTEGER_CST: |
600 | *var = build_int_cst (type, 0); | |
726a989a RB |
601 | *off = fold_convert (ssizetype, op0); |
602 | return true; | |
86a07404 | 603 | |
5be014d5 | 604 | case POINTER_PLUS_EXPR: |
726a989a | 605 | ocode = PLUS_EXPR; |
5be014d5 | 606 | /* FALLTHROUGH */ |
3cb960c7 ZD |
607 | case PLUS_EXPR: |
608 | case MINUS_EXPR: | |
726a989a RB |
609 | split_constant_offset (op0, &var0, &off0); |
610 | split_constant_offset (op1, &var1, &off1); | |
611 | *var = fold_build2 (code, type, var0, var1); | |
612 | *off = size_binop (ocode, off0, off1); | |
613 | return true; | |
86a07404 | 614 | |
86a07404 | 615 | case MULT_EXPR: |
726a989a RB |
616 | if (TREE_CODE (op1) != INTEGER_CST) |
617 | return false; | |
3cb960c7 | 618 | |
726a989a RB |
619 | split_constant_offset (op0, &var0, &off0); |
620 | *var = fold_build2 (MULT_EXPR, type, var0, op1); | |
621 | *off = size_binop (MULT_EXPR, off0, fold_convert (ssizetype, op1)); | |
622 | return true; | |
86a07404 | 623 | |
3cb960c7 ZD |
624 | case ADDR_EXPR: |
625 | { | |
726a989a | 626 | tree base, poffset; |
3cb960c7 | 627 | HOST_WIDE_INT pbitsize, pbitpos; |
ef4bddc2 | 628 | machine_mode pmode; |
3cb960c7 | 629 | int punsignedp, pvolatilep; |
86a07404 | 630 | |
da4b6efc | 631 | op0 = TREE_OPERAND (op0, 0); |
726a989a | 632 | base = get_inner_reference (op0, &pbitsize, &pbitpos, &poffset, |
b3ecff82 | 633 | &pmode, &punsignedp, &pvolatilep, false); |
86a07404 | 634 | |
3cb960c7 | 635 | if (pbitpos % BITS_PER_UNIT != 0) |
726a989a | 636 | return false; |
3cb960c7 ZD |
637 | base = build_fold_addr_expr (base); |
638 | off0 = ssize_int (pbitpos / BITS_PER_UNIT); | |
86a07404 | 639 | |
3cb960c7 ZD |
640 | if (poffset) |
641 | { | |
642 | split_constant_offset (poffset, &poffset, &off1); | |
643 | off0 = size_binop (PLUS_EXPR, off0, off1); | |
36ad7922 | 644 | if (POINTER_TYPE_P (TREE_TYPE (base))) |
5d49b6a7 | 645 | base = fold_build_pointer_plus (base, poffset); |
36ad7922 JJ |
646 | else |
647 | base = fold_build2 (PLUS_EXPR, TREE_TYPE (base), base, | |
648 | fold_convert (TREE_TYPE (base), poffset)); | |
3cb960c7 ZD |
649 | } |
650 | ||
6481b879 JJ |
651 | var0 = fold_convert (type, base); |
652 | ||
653 | /* If variable length types are involved, punt, otherwise casts | |
654 | might be converted into ARRAY_REFs in gimplify_conversion. | |
655 | To compute that ARRAY_REF's element size TYPE_SIZE_UNIT, which | |
656 | possibly no longer appears in current GIMPLE, might resurface. | |
657 | This perhaps could run | |
1a87cf0c | 658 | if (CONVERT_EXPR_P (var0)) |
6481b879 JJ |
659 | { |
660 | gimplify_conversion (&var0); | |
661 | // Attempt to fill in any within var0 found ARRAY_REF's | |
662 | // element size from corresponding op embedded ARRAY_REF, | |
663 | // if unsuccessful, just punt. | |
664 | } */ | |
665 | while (POINTER_TYPE_P (type)) | |
666 | type = TREE_TYPE (type); | |
667 | if (int_size_in_bytes (type) < 0) | |
726a989a | 668 | return false; |
6481b879 JJ |
669 | |
670 | *var = var0; | |
3cb960c7 | 671 | *off = off0; |
726a989a | 672 | return true; |
3cb960c7 | 673 | } |
86a07404 | 674 | |
06cb4f79 JS |
675 | case SSA_NAME: |
676 | { | |
726a989a RB |
677 | gimple def_stmt = SSA_NAME_DEF_STMT (op0); |
678 | enum tree_code subcode; | |
06cb4f79 | 679 | |
726a989a RB |
680 | if (gimple_code (def_stmt) != GIMPLE_ASSIGN) |
681 | return false; | |
682 | ||
683 | var0 = gimple_assign_rhs1 (def_stmt); | |
684 | subcode = gimple_assign_rhs_code (def_stmt); | |
685 | var1 = gimple_assign_rhs2 (def_stmt); | |
686 | ||
687 | return split_constant_offset_1 (type, var0, subcode, var1, var, off); | |
06cb4f79 | 688 | } |
b61b1f17 MM |
689 | CASE_CONVERT: |
690 | { | |
691 | /* We must not introduce undefined overflow, and we must not change the value. | |
692 | Hence we're okay if the inner type doesn't overflow to start with | |
693 | (pointer or signed), the outer type also is an integer or pointer | |
694 | and the outer precision is at least as large as the inner. */ | |
695 | tree itype = TREE_TYPE (op0); | |
696 | if ((POINTER_TYPE_P (itype) | |
697 | || (INTEGRAL_TYPE_P (itype) && TYPE_OVERFLOW_UNDEFINED (itype))) | |
698 | && TYPE_PRECISION (type) >= TYPE_PRECISION (itype) | |
699 | && (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type))) | |
700 | { | |
701 | split_constant_offset (op0, &var0, off); | |
702 | *var = fold_convert (type, var0); | |
703 | return true; | |
704 | } | |
705 | return false; | |
706 | } | |
06cb4f79 | 707 | |
86a07404 | 708 | default: |
726a989a | 709 | return false; |
86a07404 | 710 | } |
726a989a RB |
711 | } |
712 | ||
713 | /* Expresses EXP as VAR + OFF, where off is a constant. The type of OFF | |
714 | will be ssizetype. */ | |
715 | ||
716 | void | |
717 | split_constant_offset (tree exp, tree *var, tree *off) | |
718 | { | |
719 | tree type = TREE_TYPE (exp), otype, op0, op1, e, o; | |
720 | enum tree_code code; | |
86a07404 | 721 | |
726a989a | 722 | *var = exp; |
3cb960c7 | 723 | *off = ssize_int (0); |
726a989a RB |
724 | STRIP_NOPS (exp); |
725 | ||
ffd78b30 RG |
726 | if (tree_is_chrec (exp) |
727 | || get_gimple_rhs_class (TREE_CODE (exp)) == GIMPLE_TERNARY_RHS) | |
726a989a RB |
728 | return; |
729 | ||
730 | otype = TREE_TYPE (exp); | |
731 | code = TREE_CODE (exp); | |
732 | extract_ops_from_tree (exp, &code, &op0, &op1); | |
733 | if (split_constant_offset_1 (otype, op0, code, op1, &e, &o)) | |
734 | { | |
735 | *var = fold_convert (type, e); | |
736 | *off = o; | |
737 | } | |
86a07404 IR |
738 | } |
739 | ||
3cb960c7 ZD |
740 | /* Returns the address ADDR of an object in a canonical shape (without nop |
741 | casts, and with type of pointer to the object). */ | |
86a07404 IR |
742 | |
743 | static tree | |
3cb960c7 | 744 | canonicalize_base_object_address (tree addr) |
86a07404 | 745 | { |
bbc8a8dc ZD |
746 | tree orig = addr; |
747 | ||
3cb960c7 | 748 | STRIP_NOPS (addr); |
86a07404 | 749 | |
bbc8a8dc ZD |
750 | /* The base address may be obtained by casting from integer, in that case |
751 | keep the cast. */ | |
752 | if (!POINTER_TYPE_P (TREE_TYPE (addr))) | |
753 | return orig; | |
754 | ||
3cb960c7 ZD |
755 | if (TREE_CODE (addr) != ADDR_EXPR) |
756 | return addr; | |
86a07404 | 757 | |
3cb960c7 | 758 | return build_fold_addr_expr (TREE_OPERAND (addr, 0)); |
86a07404 IR |
759 | } |
760 | ||
b8698a0f | 761 | /* Analyzes the behavior of the memory reference DR in the innermost loop or |
4e4452b6 | 762 | basic block that contains it. Returns true if analysis succeed or false |
a70d6342 | 763 | otherwise. */ |
86a07404 | 764 | |
3661e899 | 765 | bool |
4e4452b6 | 766 | dr_analyze_innermost (struct data_reference *dr, struct loop *nest) |
86a07404 | 767 | { |
726a989a | 768 | gimple stmt = DR_STMT (dr); |
3cb960c7 ZD |
769 | struct loop *loop = loop_containing_stmt (stmt); |
770 | tree ref = DR_REF (dr); | |
86a07404 | 771 | HOST_WIDE_INT pbitsize, pbitpos; |
3cb960c7 | 772 | tree base, poffset; |
ef4bddc2 | 773 | machine_mode pmode; |
86a07404 | 774 | int punsignedp, pvolatilep; |
3cb960c7 ZD |
775 | affine_iv base_iv, offset_iv; |
776 | tree init, dinit, step; | |
a70d6342 | 777 | bool in_loop = (loop && loop->num); |
3cb960c7 ZD |
778 | |
779 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
780 | fprintf (dump_file, "analyze_innermost: "); | |
86a07404 | 781 | |
3cb960c7 | 782 | base = get_inner_reference (ref, &pbitsize, &pbitpos, &poffset, |
b3ecff82 | 783 | &pmode, &punsignedp, &pvolatilep, false); |
3cb960c7 | 784 | gcc_assert (base != NULL_TREE); |
86a07404 | 785 | |
3cb960c7 | 786 | if (pbitpos % BITS_PER_UNIT != 0) |
86a07404 | 787 | { |
3cb960c7 ZD |
788 | if (dump_file && (dump_flags & TDF_DETAILS)) |
789 | fprintf (dump_file, "failed: bit offset alignment.\n"); | |
3661e899 | 790 | return false; |
3cb960c7 | 791 | } |
86a07404 | 792 | |
70f34814 RG |
793 | if (TREE_CODE (base) == MEM_REF) |
794 | { | |
795 | if (!integer_zerop (TREE_OPERAND (base, 1))) | |
796 | { | |
807e902e KZ |
797 | offset_int moff = mem_ref_offset (base); |
798 | tree mofft = wide_int_to_tree (sizetype, moff); | |
70f34814 | 799 | if (!poffset) |
673910d7 | 800 | poffset = mofft; |
70f34814 | 801 | else |
673910d7 | 802 | poffset = size_binop (PLUS_EXPR, poffset, mofft); |
70f34814 RG |
803 | } |
804 | base = TREE_OPERAND (base, 0); | |
805 | } | |
806 | else | |
807 | base = build_fold_addr_expr (base); | |
4e4452b6 | 808 | |
a70d6342 | 809 | if (in_loop) |
3cb960c7 | 810 | { |
b8698a0f | 811 | if (!simple_iv (loop, loop_containing_stmt (stmt), base, &base_iv, |
319e6439 | 812 | nest ? true : false)) |
a70d6342 | 813 | { |
4e4452b6 IR |
814 | if (nest) |
815 | { | |
816 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
817 | fprintf (dump_file, "failed: evolution of base is not" | |
818 | " affine.\n"); | |
819 | return false; | |
820 | } | |
821 | else | |
822 | { | |
823 | base_iv.base = base; | |
824 | base_iv.step = ssize_int (0); | |
825 | base_iv.no_overflow = true; | |
826 | } | |
a70d6342 IR |
827 | } |
828 | } | |
829 | else | |
830 | { | |
831 | base_iv.base = base; | |
832 | base_iv.step = ssize_int (0); | |
833 | base_iv.no_overflow = true; | |
3cb960c7 | 834 | } |
a70d6342 | 835 | |
24adb18f | 836 | if (!poffset) |
3cb960c7 ZD |
837 | { |
838 | offset_iv.base = ssize_int (0); | |
839 | offset_iv.step = ssize_int (0); | |
840 | } | |
24adb18f | 841 | else |
3cb960c7 | 842 | { |
24adb18f IR |
843 | if (!in_loop) |
844 | { | |
845 | offset_iv.base = poffset; | |
846 | offset_iv.step = ssize_int (0); | |
847 | } | |
848 | else if (!simple_iv (loop, loop_containing_stmt (stmt), | |
319e6439 RG |
849 | poffset, &offset_iv, |
850 | nest ? true : false)) | |
24adb18f | 851 | { |
4e4452b6 IR |
852 | if (nest) |
853 | { | |
854 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
855 | fprintf (dump_file, "failed: evolution of offset is not" | |
856 | " affine.\n"); | |
857 | return false; | |
858 | } | |
859 | else | |
860 | { | |
861 | offset_iv.base = poffset; | |
862 | offset_iv.step = ssize_int (0); | |
863 | } | |
24adb18f | 864 | } |
3cb960c7 | 865 | } |
86a07404 | 866 | |
3cb960c7 ZD |
867 | init = ssize_int (pbitpos / BITS_PER_UNIT); |
868 | split_constant_offset (base_iv.base, &base_iv.base, &dinit); | |
869 | init = size_binop (PLUS_EXPR, init, dinit); | |
870 | split_constant_offset (offset_iv.base, &offset_iv.base, &dinit); | |
871 | init = size_binop (PLUS_EXPR, init, dinit); | |
86a07404 | 872 | |
3cb960c7 ZD |
873 | step = size_binop (PLUS_EXPR, |
874 | fold_convert (ssizetype, base_iv.step), | |
875 | fold_convert (ssizetype, offset_iv.step)); | |
86a07404 | 876 | |
3cb960c7 | 877 | DR_BASE_ADDRESS (dr) = canonicalize_base_object_address (base_iv.base); |
86a07404 | 878 | |
3cb960c7 ZD |
879 | DR_OFFSET (dr) = fold_convert (ssizetype, offset_iv.base); |
880 | DR_INIT (dr) = init; | |
881 | DR_STEP (dr) = step; | |
86a07404 | 882 | |
3cb960c7 | 883 | DR_ALIGNED_TO (dr) = size_int (highest_pow2_factor (offset_iv.base)); |
86a07404 | 884 | |
3cb960c7 ZD |
885 | if (dump_file && (dump_flags & TDF_DETAILS)) |
886 | fprintf (dump_file, "success.\n"); | |
3661e899 TB |
887 | |
888 | return true; | |
3cb960c7 | 889 | } |
86a07404 | 890 | |
3cb960c7 | 891 | /* Determines the base object and the list of indices of memory reference |
5c640e29 | 892 | DR, analyzed in LOOP and instantiated in loop nest NEST. */ |
86a07404 | 893 | |
3cb960c7 | 894 | static void |
5c640e29 | 895 | dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop) |
3cb960c7 | 896 | { |
6e1aa848 | 897 | vec<tree> access_fns = vNULL; |
c4ddde1b | 898 | tree ref, op; |
9fcb758b RG |
899 | tree base, off, access_fn; |
900 | basic_block before_loop; | |
b8698a0f | 901 | |
9fcb758b RG |
902 | /* If analyzing a basic-block there are no indices to analyze |
903 | and thus no access functions. */ | |
02f5d6c5 RG |
904 | if (!nest) |
905 | { | |
9fcb758b | 906 | DR_BASE_OBJECT (dr) = DR_REF (dr); |
9771b263 | 907 | DR_ACCESS_FNS (dr).create (0); |
02f5d6c5 RG |
908 | return; |
909 | } | |
910 | ||
c4ddde1b | 911 | ref = DR_REF (dr); |
02f5d6c5 | 912 | before_loop = block_before_loop (nest); |
b8698a0f | 913 | |
9fcb758b RG |
914 | /* REALPART_EXPR and IMAGPART_EXPR can be handled like accesses |
915 | into a two element array with a constant index. The base is | |
916 | then just the immediate underlying object. */ | |
917 | if (TREE_CODE (ref) == REALPART_EXPR) | |
918 | { | |
919 | ref = TREE_OPERAND (ref, 0); | |
9771b263 | 920 | access_fns.safe_push (integer_zero_node); |
9fcb758b RG |
921 | } |
922 | else if (TREE_CODE (ref) == IMAGPART_EXPR) | |
923 | { | |
924 | ref = TREE_OPERAND (ref, 0); | |
9771b263 | 925 | access_fns.safe_push (integer_one_node); |
9fcb758b RG |
926 | } |
927 | ||
b8324815 | 928 | /* Analyze access functions of dimensions we know to be independent. */ |
c4ddde1b | 929 | while (handled_component_p (ref)) |
86a07404 | 930 | { |
c4ddde1b | 931 | if (TREE_CODE (ref) == ARRAY_REF) |
86a07404 | 932 | { |
c4ddde1b | 933 | op = TREE_OPERAND (ref, 1); |
02f5d6c5 RG |
934 | access_fn = analyze_scalar_evolution (loop, op); |
935 | access_fn = instantiate_scev (before_loop, loop, access_fn); | |
9771b263 | 936 | access_fns.safe_push (access_fn); |
b8324815 | 937 | } |
c4ddde1b RG |
938 | else if (TREE_CODE (ref) == COMPONENT_REF |
939 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (ref, 0))) == RECORD_TYPE) | |
940 | { | |
941 | /* For COMPONENT_REFs of records (but not unions!) use the | |
942 | FIELD_DECL offset as constant access function so we can | |
943 | disambiguate a[i].f1 and a[i].f2. */ | |
944 | tree off = component_ref_field_offset (ref); | |
945 | off = size_binop (PLUS_EXPR, | |
946 | size_binop (MULT_EXPR, | |
947 | fold_convert (bitsizetype, off), | |
948 | bitsize_int (BITS_PER_UNIT)), | |
949 | DECL_FIELD_BIT_OFFSET (TREE_OPERAND (ref, 1))); | |
9771b263 | 950 | access_fns.safe_push (off); |
c4ddde1b RG |
951 | } |
952 | else | |
953 | /* If we have an unhandled component we could not translate | |
954 | to an access function stop analyzing. We have determined | |
955 | our base object in this case. */ | |
956 | break; | |
b8698a0f | 957 | |
c4ddde1b | 958 | ref = TREE_OPERAND (ref, 0); |
86a07404 IR |
959 | } |
960 | ||
8c330caa RG |
961 | /* If the address operand of a MEM_REF base has an evolution in the |
962 | analyzed nest, add it as an additional independent access-function. */ | |
c4ddde1b | 963 | if (TREE_CODE (ref) == MEM_REF) |
86a07404 | 964 | { |
c4ddde1b | 965 | op = TREE_OPERAND (ref, 0); |
3cb960c7 | 966 | access_fn = analyze_scalar_evolution (loop, op); |
a213b219 | 967 | access_fn = instantiate_scev (before_loop, loop, access_fn); |
8c330caa | 968 | if (TREE_CODE (access_fn) == POLYNOMIAL_CHREC) |
2946bd34 | 969 | { |
0a500dd3 | 970 | tree orig_type; |
c4ddde1b | 971 | tree memoff = TREE_OPERAND (ref, 1); |
8c330caa | 972 | base = initial_condition (access_fn); |
0a500dd3 RG |
973 | orig_type = TREE_TYPE (base); |
974 | STRIP_USELESS_TYPE_CONVERSION (base); | |
8c330caa | 975 | split_constant_offset (base, &base, &off); |
f65586dc | 976 | STRIP_USELESS_TYPE_CONVERSION (base); |
8c330caa RG |
977 | /* Fold the MEM_REF offset into the evolutions initial |
978 | value to make more bases comparable. */ | |
c4ddde1b | 979 | if (!integer_zerop (memoff)) |
8c330caa RG |
980 | { |
981 | off = size_binop (PLUS_EXPR, off, | |
c4ddde1b RG |
982 | fold_convert (ssizetype, memoff)); |
983 | memoff = build_int_cst (TREE_TYPE (memoff), 0); | |
8c330caa RG |
984 | } |
985 | access_fn = chrec_replace_initial_condition | |
0a500dd3 | 986 | (access_fn, fold_convert (orig_type, off)); |
c4ddde1b RG |
987 | /* ??? This is still not a suitable base object for |
988 | dr_may_alias_p - the base object needs to be an | |
989 | access that covers the object as whole. With | |
990 | an evolution in the pointer this cannot be | |
991 | guaranteed. | |
992 | As a band-aid, mark the access so we can special-case | |
993 | it in dr_may_alias_p. */ | |
f3dccf50 | 994 | tree old = ref; |
c4ddde1b RG |
995 | ref = fold_build2_loc (EXPR_LOCATION (ref), |
996 | MEM_REF, TREE_TYPE (ref), | |
997 | base, memoff); | |
f3dccf50 RB |
998 | MR_DEPENDENCE_CLIQUE (ref) = MR_DEPENDENCE_CLIQUE (old); |
999 | MR_DEPENDENCE_BASE (ref) = MR_DEPENDENCE_BASE (old); | |
9771b263 | 1000 | access_fns.safe_push (access_fn); |
2946bd34 | 1001 | } |
86a07404 | 1002 | } |
c4ddde1b RG |
1003 | else if (DECL_P (ref)) |
1004 | { | |
1005 | /* Canonicalize DR_BASE_OBJECT to MEM_REF form. */ | |
1006 | ref = build2 (MEM_REF, TREE_TYPE (ref), | |
1007 | build_fold_addr_expr (ref), | |
1008 | build_int_cst (reference_alias_ptr_type (ref), 0)); | |
1009 | } | |
86a07404 | 1010 | |
3cb960c7 ZD |
1011 | DR_BASE_OBJECT (dr) = ref; |
1012 | DR_ACCESS_FNS (dr) = access_fns; | |
86a07404 IR |
1013 | } |
1014 | ||
3cb960c7 | 1015 | /* Extracts the alias analysis information from the memory reference DR. */ |
86a07404 | 1016 | |
3cb960c7 ZD |
1017 | static void |
1018 | dr_analyze_alias (struct data_reference *dr) | |
86a07404 | 1019 | { |
3cb960c7 | 1020 | tree ref = DR_REF (dr); |
5006671f RG |
1021 | tree base = get_base_address (ref), addr; |
1022 | ||
70f34814 RG |
1023 | if (INDIRECT_REF_P (base) |
1024 | || TREE_CODE (base) == MEM_REF) | |
3cb960c7 ZD |
1025 | { |
1026 | addr = TREE_OPERAND (base, 0); | |
1027 | if (TREE_CODE (addr) == SSA_NAME) | |
5006671f | 1028 | DR_PTR_INFO (dr) = SSA_NAME_PTR_INFO (addr); |
3cb960c7 | 1029 | } |
3cb960c7 | 1030 | } |
86a07404 | 1031 | |
3cb960c7 | 1032 | /* Frees data reference DR. */ |
8fdbc9c6 | 1033 | |
dea61d92 | 1034 | void |
8fdbc9c6 ZD |
1035 | free_data_ref (data_reference_p dr) |
1036 | { | |
9771b263 | 1037 | DR_ACCESS_FNS (dr).release (); |
8fdbc9c6 ZD |
1038 | free (dr); |
1039 | } | |
86a07404 | 1040 | |
3cb960c7 ZD |
1041 | /* Analyzes memory reference MEMREF accessed in STMT. The reference |
1042 | is read if IS_READ is true, write otherwise. Returns the | |
5c640e29 SP |
1043 | data_reference description of MEMREF. NEST is the outermost loop |
1044 | in which the reference should be instantiated, LOOP is the loop in | |
1045 | which the data reference should be analyzed. */ | |
86a07404 | 1046 | |
5417e022 | 1047 | struct data_reference * |
5c640e29 SP |
1048 | create_data_ref (loop_p nest, loop_p loop, tree memref, gimple stmt, |
1049 | bool is_read) | |
86a07404 | 1050 | { |
3cb960c7 | 1051 | struct data_reference *dr; |
0ff4040e | 1052 | |
3cb960c7 | 1053 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e | 1054 | { |
3cb960c7 ZD |
1055 | fprintf (dump_file, "Creating dr for "); |
1056 | print_generic_expr (dump_file, memref, TDF_SLIM); | |
1057 | fprintf (dump_file, "\n"); | |
0ff4040e | 1058 | } |
e2157b49 | 1059 | |
3cb960c7 ZD |
1060 | dr = XCNEW (struct data_reference); |
1061 | DR_STMT (dr) = stmt; | |
1062 | DR_REF (dr) = memref; | |
1063 | DR_IS_READ (dr) = is_read; | |
86a07404 | 1064 | |
4e4452b6 | 1065 | dr_analyze_innermost (dr, nest); |
5c640e29 | 1066 | dr_analyze_indices (dr, nest, loop); |
3cb960c7 | 1067 | dr_analyze_alias (dr); |
86a07404 IR |
1068 | |
1069 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1070 | { | |
b8324815 | 1071 | unsigned i; |
3cb960c7 | 1072 | fprintf (dump_file, "\tbase_address: "); |
86a07404 IR |
1073 | print_generic_expr (dump_file, DR_BASE_ADDRESS (dr), TDF_SLIM); |
1074 | fprintf (dump_file, "\n\toffset from base address: "); | |
1075 | print_generic_expr (dump_file, DR_OFFSET (dr), TDF_SLIM); | |
1076 | fprintf (dump_file, "\n\tconstant offset from base address: "); | |
1077 | print_generic_expr (dump_file, DR_INIT (dr), TDF_SLIM); | |
86a07404 IR |
1078 | fprintf (dump_file, "\n\tstep: "); |
1079 | print_generic_expr (dump_file, DR_STEP (dr), TDF_SLIM); | |
3cb960c7 ZD |
1080 | fprintf (dump_file, "\n\taligned to: "); |
1081 | print_generic_expr (dump_file, DR_ALIGNED_TO (dr), TDF_SLIM); | |
1082 | fprintf (dump_file, "\n\tbase_object: "); | |
1083 | print_generic_expr (dump_file, DR_BASE_OBJECT (dr), TDF_SLIM); | |
86a07404 | 1084 | fprintf (dump_file, "\n"); |
b8324815 RG |
1085 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
1086 | { | |
1087 | fprintf (dump_file, "\tAccess function %d: ", i); | |
1088 | print_generic_stmt (dump_file, DR_ACCESS_FN (dr, i), TDF_SLIM); | |
1089 | } | |
3cb960c7 ZD |
1090 | } |
1091 | ||
b8698a0f | 1092 | return dr; |
86a07404 IR |
1093 | } |
1094 | ||
bfe068c3 IR |
1095 | /* Check if OFFSET1 and OFFSET2 (DR_OFFSETs of some data-refs) are identical |
1096 | expressions. */ | |
1097 | static bool | |
1098 | dr_equal_offsets_p1 (tree offset1, tree offset2) | |
1099 | { | |
1100 | bool res; | |
1101 | ||
1102 | STRIP_NOPS (offset1); | |
1103 | STRIP_NOPS (offset2); | |
1104 | ||
1105 | if (offset1 == offset2) | |
1106 | return true; | |
1107 | ||
1108 | if (TREE_CODE (offset1) != TREE_CODE (offset2) | |
1109 | || (!BINARY_CLASS_P (offset1) && !UNARY_CLASS_P (offset1))) | |
1110 | return false; | |
1111 | ||
1112 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 0), | |
1113 | TREE_OPERAND (offset2, 0)); | |
1114 | ||
1115 | if (!res || !BINARY_CLASS_P (offset1)) | |
1116 | return res; | |
1117 | ||
1118 | res = dr_equal_offsets_p1 (TREE_OPERAND (offset1, 1), | |
1119 | TREE_OPERAND (offset2, 1)); | |
1120 | ||
1121 | return res; | |
1122 | } | |
1123 | ||
1124 | /* Check if DRA and DRB have equal offsets. */ | |
1125 | bool | |
1126 | dr_equal_offsets_p (struct data_reference *dra, | |
1127 | struct data_reference *drb) | |
1128 | { | |
1129 | tree offset1, offset2; | |
1130 | ||
1131 | offset1 = DR_OFFSET (dra); | |
1132 | offset2 = DR_OFFSET (drb); | |
1133 | ||
1134 | return dr_equal_offsets_p1 (offset1, offset2); | |
1135 | } | |
1136 | ||
d93817c4 ZD |
1137 | /* Returns true if FNA == FNB. */ |
1138 | ||
1139 | static bool | |
1140 | affine_function_equal_p (affine_fn fna, affine_fn fnb) | |
1141 | { | |
9771b263 | 1142 | unsigned i, n = fna.length (); |
86a07404 | 1143 | |
9771b263 | 1144 | if (n != fnb.length ()) |
f86289d5 | 1145 | return false; |
86df10e3 | 1146 | |
d93817c4 | 1147 | for (i = 0; i < n; i++) |
9771b263 | 1148 | if (!operand_equal_p (fna[i], fnb[i], 0)) |
d93817c4 ZD |
1149 | return false; |
1150 | ||
1151 | return true; | |
1152 | } | |
1153 | ||
1154 | /* If all the functions in CF are the same, returns one of them, | |
1155 | otherwise returns NULL. */ | |
1156 | ||
1157 | static affine_fn | |
1158 | common_affine_function (conflict_function *cf) | |
86df10e3 | 1159 | { |
d93817c4 ZD |
1160 | unsigned i; |
1161 | affine_fn comm; | |
1162 | ||
1163 | if (!CF_NONTRIVIAL_P (cf)) | |
c3284718 | 1164 | return affine_fn (); |
d93817c4 ZD |
1165 | |
1166 | comm = cf->fns[0]; | |
1167 | ||
1168 | for (i = 1; i < cf->n; i++) | |
1169 | if (!affine_function_equal_p (comm, cf->fns[i])) | |
c3284718 | 1170 | return affine_fn (); |
d93817c4 ZD |
1171 | |
1172 | return comm; | |
1173 | } | |
86df10e3 | 1174 | |
d93817c4 ZD |
1175 | /* Returns the base of the affine function FN. */ |
1176 | ||
1177 | static tree | |
1178 | affine_function_base (affine_fn fn) | |
1179 | { | |
9771b263 | 1180 | return fn[0]; |
d93817c4 ZD |
1181 | } |
1182 | ||
1183 | /* Returns true if FN is a constant. */ | |
1184 | ||
1185 | static bool | |
1186 | affine_function_constant_p (affine_fn fn) | |
1187 | { | |
1188 | unsigned i; | |
1189 | tree coef; | |
1190 | ||
9771b263 | 1191 | for (i = 1; fn.iterate (i, &coef); i++) |
d93817c4 | 1192 | if (!integer_zerop (coef)) |
e2157b49 SP |
1193 | return false; |
1194 | ||
86df10e3 SP |
1195 | return true; |
1196 | } | |
1197 | ||
1baf2906 SP |
1198 | /* Returns true if FN is the zero constant function. */ |
1199 | ||
1200 | static bool | |
1201 | affine_function_zero_p (affine_fn fn) | |
1202 | { | |
1203 | return (integer_zerop (affine_function_base (fn)) | |
1204 | && affine_function_constant_p (fn)); | |
1205 | } | |
1206 | ||
33b30201 SP |
1207 | /* Returns a signed integer type with the largest precision from TA |
1208 | and TB. */ | |
1209 | ||
1210 | static tree | |
1211 | signed_type_for_types (tree ta, tree tb) | |
1212 | { | |
1213 | if (TYPE_PRECISION (ta) > TYPE_PRECISION (tb)) | |
1214 | return signed_type_for (ta); | |
1215 | else | |
1216 | return signed_type_for (tb); | |
1217 | } | |
1218 | ||
d93817c4 ZD |
1219 | /* Applies operation OP on affine functions FNA and FNB, and returns the |
1220 | result. */ | |
1221 | ||
1222 | static affine_fn | |
1223 | affine_fn_op (enum tree_code op, affine_fn fna, affine_fn fnb) | |
1224 | { | |
1225 | unsigned i, n, m; | |
1226 | affine_fn ret; | |
1227 | tree coef; | |
1228 | ||
9771b263 | 1229 | if (fnb.length () > fna.length ()) |
d93817c4 | 1230 | { |
9771b263 DN |
1231 | n = fna.length (); |
1232 | m = fnb.length (); | |
d93817c4 ZD |
1233 | } |
1234 | else | |
1235 | { | |
9771b263 DN |
1236 | n = fnb.length (); |
1237 | m = fna.length (); | |
d93817c4 ZD |
1238 | } |
1239 | ||
9771b263 | 1240 | ret.create (m); |
d93817c4 | 1241 | for (i = 0; i < n; i++) |
33b30201 | 1242 | { |
9771b263 DN |
1243 | tree type = signed_type_for_types (TREE_TYPE (fna[i]), |
1244 | TREE_TYPE (fnb[i])); | |
1245 | ret.quick_push (fold_build2 (op, type, fna[i], fnb[i])); | |
33b30201 | 1246 | } |
d93817c4 | 1247 | |
9771b263 DN |
1248 | for (; fna.iterate (i, &coef); i++) |
1249 | ret.quick_push (fold_build2 (op, signed_type_for (TREE_TYPE (coef)), | |
d93817c4 | 1250 | coef, integer_zero_node)); |
9771b263 DN |
1251 | for (; fnb.iterate (i, &coef); i++) |
1252 | ret.quick_push (fold_build2 (op, signed_type_for (TREE_TYPE (coef)), | |
d93817c4 ZD |
1253 | integer_zero_node, coef)); |
1254 | ||
1255 | return ret; | |
1256 | } | |
1257 | ||
1258 | /* Returns the sum of affine functions FNA and FNB. */ | |
1259 | ||
1260 | static affine_fn | |
1261 | affine_fn_plus (affine_fn fna, affine_fn fnb) | |
1262 | { | |
1263 | return affine_fn_op (PLUS_EXPR, fna, fnb); | |
1264 | } | |
1265 | ||
1266 | /* Returns the difference of affine functions FNA and FNB. */ | |
1267 | ||
1268 | static affine_fn | |
1269 | affine_fn_minus (affine_fn fna, affine_fn fnb) | |
1270 | { | |
1271 | return affine_fn_op (MINUS_EXPR, fna, fnb); | |
1272 | } | |
1273 | ||
1274 | /* Frees affine function FN. */ | |
1275 | ||
1276 | static void | |
1277 | affine_fn_free (affine_fn fn) | |
1278 | { | |
9771b263 | 1279 | fn.release (); |
d93817c4 ZD |
1280 | } |
1281 | ||
86df10e3 SP |
1282 | /* Determine for each subscript in the data dependence relation DDR |
1283 | the distance. */ | |
56cf8686 | 1284 | |
0ff4040e | 1285 | static void |
86df10e3 | 1286 | compute_subscript_distance (struct data_dependence_relation *ddr) |
56cf8686 | 1287 | { |
d93817c4 ZD |
1288 | conflict_function *cf_a, *cf_b; |
1289 | affine_fn fn_a, fn_b, diff; | |
1290 | ||
56cf8686 SP |
1291 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
1292 | { | |
1293 | unsigned int i; | |
b8698a0f | 1294 | |
56cf8686 SP |
1295 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
1296 | { | |
56cf8686 | 1297 | struct subscript *subscript; |
b8698a0f | 1298 | |
56cf8686 | 1299 | subscript = DDR_SUBSCRIPT (ddr, i); |
d93817c4 ZD |
1300 | cf_a = SUB_CONFLICTS_IN_A (subscript); |
1301 | cf_b = SUB_CONFLICTS_IN_B (subscript); | |
86df10e3 | 1302 | |
d93817c4 ZD |
1303 | fn_a = common_affine_function (cf_a); |
1304 | fn_b = common_affine_function (cf_b); | |
9771b263 | 1305 | if (!fn_a.exists () || !fn_b.exists ()) |
86df10e3 | 1306 | { |
d93817c4 ZD |
1307 | SUB_DISTANCE (subscript) = chrec_dont_know; |
1308 | return; | |
86df10e3 | 1309 | } |
d93817c4 | 1310 | diff = affine_fn_minus (fn_a, fn_b); |
b8698a0f | 1311 | |
d93817c4 ZD |
1312 | if (affine_function_constant_p (diff)) |
1313 | SUB_DISTANCE (subscript) = affine_function_base (diff); | |
56cf8686 SP |
1314 | else |
1315 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
d93817c4 ZD |
1316 | |
1317 | affine_fn_free (diff); | |
56cf8686 SP |
1318 | } |
1319 | } | |
1320 | } | |
1321 | ||
d93817c4 ZD |
1322 | /* Returns the conflict function for "unknown". */ |
1323 | ||
1324 | static conflict_function * | |
1325 | conflict_fn_not_known (void) | |
1326 | { | |
1327 | conflict_function *fn = XCNEW (conflict_function); | |
1328 | fn->n = NOT_KNOWN; | |
1329 | ||
1330 | return fn; | |
1331 | } | |
1332 | ||
1333 | /* Returns the conflict function for "independent". */ | |
1334 | ||
1335 | static conflict_function * | |
1336 | conflict_fn_no_dependence (void) | |
1337 | { | |
1338 | conflict_function *fn = XCNEW (conflict_function); | |
1339 | fn->n = NO_DEPENDENCE; | |
1340 | ||
1341 | return fn; | |
1342 | } | |
1343 | ||
3cb960c7 ZD |
1344 | /* Returns true if the address of OBJ is invariant in LOOP. */ |
1345 | ||
1346 | static bool | |
ed7a4b4b | 1347 | object_address_invariant_in_loop_p (const struct loop *loop, const_tree obj) |
3cb960c7 ZD |
1348 | { |
1349 | while (handled_component_p (obj)) | |
1350 | { | |
1351 | if (TREE_CODE (obj) == ARRAY_REF) | |
1352 | { | |
1353 | /* Index of the ARRAY_REF was zeroed in analyze_indices, thus we only | |
1354 | need to check the stride and the lower bound of the reference. */ | |
1355 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1356 | loop->num) | |
1357 | || chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 3), | |
1358 | loop->num)) | |
1359 | return false; | |
1360 | } | |
1361 | else if (TREE_CODE (obj) == COMPONENT_REF) | |
1362 | { | |
1363 | if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 2), | |
1364 | loop->num)) | |
1365 | return false; | |
1366 | } | |
1367 | obj = TREE_OPERAND (obj, 0); | |
1368 | } | |
1369 | ||
70f34814 RG |
1370 | if (!INDIRECT_REF_P (obj) |
1371 | && TREE_CODE (obj) != MEM_REF) | |
3cb960c7 ZD |
1372 | return true; |
1373 | ||
1374 | return !chrec_contains_symbols_defined_in_loop (TREE_OPERAND (obj, 0), | |
1375 | loop->num); | |
1376 | } | |
1377 | ||
3cb960c7 | 1378 | /* Returns false if we can prove that data references A and B do not alias, |
02f5d6c5 RG |
1379 | true otherwise. If LOOP_NEST is false no cross-iteration aliases are |
1380 | considered. */ | |
3cb960c7 | 1381 | |
f8bf9252 | 1382 | bool |
02f5d6c5 RG |
1383 | dr_may_alias_p (const struct data_reference *a, const struct data_reference *b, |
1384 | bool loop_nest) | |
3cb960c7 | 1385 | { |
7d36e538 RG |
1386 | tree addr_a = DR_BASE_OBJECT (a); |
1387 | tree addr_b = DR_BASE_OBJECT (b); | |
3cb960c7 | 1388 | |
02f5d6c5 RG |
1389 | /* If we are not processing a loop nest but scalar code we |
1390 | do not need to care about possible cross-iteration dependences | |
1391 | and thus can process the full original reference. Do so, | |
1392 | similar to how loop invariant motion applies extra offset-based | |
1393 | disambiguation. */ | |
1394 | if (!loop_nest) | |
1395 | { | |
1396 | aff_tree off1, off2; | |
807e902e | 1397 | widest_int size1, size2; |
02f5d6c5 RG |
1398 | get_inner_reference_aff (DR_REF (a), &off1, &size1); |
1399 | get_inner_reference_aff (DR_REF (b), &off2, &size2); | |
807e902e | 1400 | aff_combination_scale (&off1, -1); |
02f5d6c5 RG |
1401 | aff_combination_add (&off2, &off1); |
1402 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) | |
1403 | return false; | |
1404 | } | |
1405 | ||
f3dccf50 RB |
1406 | if ((TREE_CODE (addr_a) == MEM_REF || TREE_CODE (addr_a) == TARGET_MEM_REF) |
1407 | && (TREE_CODE (addr_b) == MEM_REF || TREE_CODE (addr_b) == TARGET_MEM_REF) | |
1408 | && MR_DEPENDENCE_CLIQUE (addr_a) == MR_DEPENDENCE_CLIQUE (addr_b) | |
1409 | && MR_DEPENDENCE_BASE (addr_a) != MR_DEPENDENCE_BASE (addr_b)) | |
1410 | return false; | |
1411 | ||
6e2028ff RB |
1412 | /* If we had an evolution in a pointer-based MEM_REF BASE_OBJECT we |
1413 | do not know the size of the base-object. So we cannot do any | |
1414 | offset/overlap based analysis but have to rely on points-to | |
1415 | information only. */ | |
c4ddde1b | 1416 | if (TREE_CODE (addr_a) == MEM_REF |
6e2028ff | 1417 | && TREE_CODE (TREE_OPERAND (addr_a, 0)) == SSA_NAME) |
c4ddde1b | 1418 | { |
6e2028ff RB |
1419 | /* For true dependences we can apply TBAA. */ |
1420 | if (flag_strict_aliasing | |
1421 | && DR_IS_WRITE (a) && DR_IS_READ (b) | |
1422 | && !alias_sets_conflict_p (get_alias_set (DR_REF (a)), | |
1423 | get_alias_set (DR_REF (b)))) | |
1424 | return false; | |
1425 | if (TREE_CODE (addr_b) == MEM_REF) | |
c4ddde1b RG |
1426 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), |
1427 | TREE_OPERAND (addr_b, 0)); | |
1428 | else | |
1429 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), | |
1430 | build_fold_addr_expr (addr_b)); | |
1431 | } | |
1432 | else if (TREE_CODE (addr_b) == MEM_REF | |
6e2028ff RB |
1433 | && TREE_CODE (TREE_OPERAND (addr_b, 0)) == SSA_NAME) |
1434 | { | |
1435 | /* For true dependences we can apply TBAA. */ | |
1436 | if (flag_strict_aliasing | |
1437 | && DR_IS_WRITE (a) && DR_IS_READ (b) | |
1438 | && !alias_sets_conflict_p (get_alias_set (DR_REF (a)), | |
1439 | get_alias_set (DR_REF (b)))) | |
1440 | return false; | |
1441 | if (TREE_CODE (addr_a) == MEM_REF) | |
1442 | return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0), | |
1443 | TREE_OPERAND (addr_b, 0)); | |
1444 | else | |
1445 | return ptr_derefs_may_alias_p (build_fold_addr_expr (addr_a), | |
1446 | TREE_OPERAND (addr_b, 0)); | |
1447 | } | |
c4ddde1b RG |
1448 | |
1449 | /* Otherwise DR_BASE_OBJECT is an access that covers the whole object | |
1450 | that is being subsetted in the loop nest. */ | |
b0af49c4 | 1451 | if (DR_IS_WRITE (a) && DR_IS_WRITE (b)) |
7d36e538 | 1452 | return refs_output_dependent_p (addr_a, addr_b); |
b0af49c4 | 1453 | else if (DR_IS_READ (a) && DR_IS_WRITE (b)) |
7d36e538 RG |
1454 | return refs_anti_dependent_p (addr_a, addr_b); |
1455 | return refs_may_alias_p (addr_a, addr_b); | |
3cb960c7 ZD |
1456 | } |
1457 | ||
0ff4040e SP |
1458 | /* Initialize a data dependence relation between data accesses A and |
1459 | B. NB_LOOPS is the number of loops surrounding the references: the | |
1460 | size of the classic distance/direction vectors. */ | |
56cf8686 | 1461 | |
aec7ae7d | 1462 | struct data_dependence_relation * |
b8698a0f | 1463 | initialize_data_dependence_relation (struct data_reference *a, |
0ff4040e | 1464 | struct data_reference *b, |
9771b263 | 1465 | vec<loop_p> loop_nest) |
56cf8686 SP |
1466 | { |
1467 | struct data_dependence_relation *res; | |
0ff4040e | 1468 | unsigned int i; |
b8698a0f | 1469 | |
5ed6ace5 | 1470 | res = XNEW (struct data_dependence_relation); |
56cf8686 SP |
1471 | DDR_A (res) = a; |
1472 | DDR_B (res) = b; | |
9771b263 | 1473 | DDR_LOOP_NEST (res).create (0); |
71d5b5e1 | 1474 | DDR_REVERSED_P (res) = false; |
9771b263 DN |
1475 | DDR_SUBSCRIPTS (res).create (0); |
1476 | DDR_DIR_VECTS (res).create (0); | |
1477 | DDR_DIST_VECTS (res).create (0); | |
56cf8686 | 1478 | |
86a07404 IR |
1479 | if (a == NULL || b == NULL) |
1480 | { | |
b8698a0f | 1481 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 | 1482 | return res; |
b8698a0f | 1483 | } |
86a07404 | 1484 | |
3cb960c7 | 1485 | /* If the data references do not alias, then they are independent. */ |
9771b263 | 1486 | if (!dr_may_alias_p (a, b, loop_nest.exists ())) |
86a07404 | 1487 | { |
b8698a0f | 1488 | DDR_ARE_DEPENDENT (res) = chrec_known; |
86a07404 IR |
1489 | return res; |
1490 | } | |
56cf8686 | 1491 | |
fea99a37 | 1492 | /* The case where the references are exactly the same. */ |
b3924be9 SP |
1493 | if (operand_equal_p (DR_REF (a), DR_REF (b), 0)) |
1494 | { | |
9771b263 DN |
1495 | if (loop_nest.exists () |
1496 | && !object_address_invariant_in_loop_p (loop_nest[0], | |
1a4571cb RL |
1497 | DR_BASE_OBJECT (a))) |
1498 | { | |
1499 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1500 | return res; | |
1501 | } | |
b3924be9 SP |
1502 | DDR_AFFINE_P (res) = true; |
1503 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
9771b263 | 1504 | DDR_SUBSCRIPTS (res).create (DR_NUM_DIMENSIONS (a)); |
b3924be9 SP |
1505 | DDR_LOOP_NEST (res) = loop_nest; |
1506 | DDR_INNER_LOOP (res) = 0; | |
1507 | DDR_SELF_REFERENCE (res) = true; | |
1a4571cb RL |
1508 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1509 | { | |
1510 | struct subscript *subscript; | |
1511 | ||
1512 | subscript = XNEW (struct subscript); | |
1513 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); | |
1514 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
1515 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; | |
1516 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
9771b263 | 1517 | DDR_SUBSCRIPTS (res).safe_push (subscript); |
1a4571cb | 1518 | } |
b3924be9 SP |
1519 | return res; |
1520 | } | |
1521 | ||
3cb960c7 ZD |
1522 | /* If the references do not access the same object, we do not know |
1523 | whether they alias or not. */ | |
1524 | if (!operand_equal_p (DR_BASE_OBJECT (a), DR_BASE_OBJECT (b), 0)) | |
56cf8686 | 1525 | { |
b8698a0f | 1526 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1527 | return res; |
1528 | } | |
0ff4040e | 1529 | |
3cb960c7 | 1530 | /* If the base of the object is not invariant in the loop nest, we cannot |
0d52bcc1 | 1531 | analyze it. TODO -- in fact, it would suffice to record that there may |
c80b4100 | 1532 | be arbitrary dependences in the loops where the base object varies. */ |
9771b263 DN |
1533 | if (loop_nest.exists () |
1534 | && !object_address_invariant_in_loop_p (loop_nest[0], | |
a70d6342 | 1535 | DR_BASE_OBJECT (a))) |
86a07404 | 1536 | { |
b8698a0f | 1537 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; |
86a07404 IR |
1538 | return res; |
1539 | } | |
3cb960c7 | 1540 | |
19368333 RG |
1541 | /* If the number of dimensions of the access to not agree we can have |
1542 | a pointer access to a component of the array element type and an | |
1543 | array access while the base-objects are still the same. Punt. */ | |
1544 | if (DR_NUM_DIMENSIONS (a) != DR_NUM_DIMENSIONS (b)) | |
1545 | { | |
1546 | DDR_ARE_DEPENDENT (res) = chrec_dont_know; | |
1547 | return res; | |
1548 | } | |
3cb960c7 | 1549 | |
86a07404 IR |
1550 | DDR_AFFINE_P (res) = true; |
1551 | DDR_ARE_DEPENDENT (res) = NULL_TREE; | |
9771b263 | 1552 | DDR_SUBSCRIPTS (res).create (DR_NUM_DIMENSIONS (a)); |
ba42e045 | 1553 | DDR_LOOP_NEST (res) = loop_nest; |
3d8864c0 | 1554 | DDR_INNER_LOOP (res) = 0; |
b3924be9 | 1555 | DDR_SELF_REFERENCE (res) = false; |
304afda6 | 1556 | |
86a07404 IR |
1557 | for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) |
1558 | { | |
1559 | struct subscript *subscript; | |
b8698a0f | 1560 | |
5ed6ace5 | 1561 | subscript = XNEW (struct subscript); |
d93817c4 ZD |
1562 | SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known (); |
1563 | SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known (); | |
86a07404 IR |
1564 | SUB_LAST_CONFLICT (subscript) = chrec_dont_know; |
1565 | SUB_DISTANCE (subscript) = chrec_dont_know; | |
9771b263 | 1566 | DDR_SUBSCRIPTS (res).safe_push (subscript); |
56cf8686 | 1567 | } |
ebf78a47 | 1568 | |
56cf8686 SP |
1569 | return res; |
1570 | } | |
1571 | ||
d93817c4 ZD |
1572 | /* Frees memory used by the conflict function F. */ |
1573 | ||
1574 | static void | |
1575 | free_conflict_function (conflict_function *f) | |
1576 | { | |
1577 | unsigned i; | |
1578 | ||
1579 | if (CF_NONTRIVIAL_P (f)) | |
1580 | { | |
1581 | for (i = 0; i < f->n; i++) | |
1582 | affine_fn_free (f->fns[i]); | |
1583 | } | |
1584 | free (f); | |
1585 | } | |
1586 | ||
1587 | /* Frees memory used by SUBSCRIPTS. */ | |
1588 | ||
1589 | static void | |
9771b263 | 1590 | free_subscripts (vec<subscript_p> subscripts) |
d93817c4 ZD |
1591 | { |
1592 | unsigned i; | |
1593 | subscript_p s; | |
1594 | ||
9771b263 | 1595 | FOR_EACH_VEC_ELT (subscripts, i, s) |
d93817c4 ZD |
1596 | { |
1597 | free_conflict_function (s->conflicting_iterations_in_a); | |
1598 | free_conflict_function (s->conflicting_iterations_in_b); | |
a0044be5 | 1599 | free (s); |
d93817c4 | 1600 | } |
9771b263 | 1601 | subscripts.release (); |
d93817c4 ZD |
1602 | } |
1603 | ||
56cf8686 SP |
1604 | /* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap |
1605 | description. */ | |
1606 | ||
1607 | static inline void | |
b8698a0f | 1608 | finalize_ddr_dependent (struct data_dependence_relation *ddr, |
56cf8686 SP |
1609 | tree chrec) |
1610 | { | |
b8698a0f | 1611 | DDR_ARE_DEPENDENT (ddr) = chrec; |
d93817c4 | 1612 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
9771b263 | 1613 | DDR_SUBSCRIPTS (ddr).create (0); |
56cf8686 SP |
1614 | } |
1615 | ||
86df10e3 SP |
1616 | /* The dependence relation DDR cannot be represented by a distance |
1617 | vector. */ | |
1618 | ||
1619 | static inline void | |
1620 | non_affine_dependence_relation (struct data_dependence_relation *ddr) | |
1621 | { | |
1622 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1623 | fprintf (dump_file, "(Dependence relation cannot be represented by distance vector.) \n"); | |
1624 | ||
1625 | DDR_AFFINE_P (ddr) = false; | |
1626 | } | |
1627 | ||
56cf8686 SP |
1628 | \f |
1629 | ||
1630 | /* This section contains the classic Banerjee tests. */ | |
1631 | ||
1632 | /* Returns true iff CHREC_A and CHREC_B are not dependent on any index | |
1633 | variables, i.e., if the ZIV (Zero Index Variable) test is true. */ | |
1634 | ||
1635 | static inline bool | |
ed7a4b4b | 1636 | ziv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1637 | { |
1638 | return (evolution_function_is_constant_p (chrec_a) | |
1639 | && evolution_function_is_constant_p (chrec_b)); | |
1640 | } | |
1641 | ||
1642 | /* Returns true iff CHREC_A and CHREC_B are dependent on an index | |
1643 | variable, i.e., if the SIV (Single Index Variable) test is true. */ | |
1644 | ||
1645 | static bool | |
ed7a4b4b | 1646 | siv_subscript_p (const_tree chrec_a, const_tree chrec_b) |
56cf8686 SP |
1647 | { |
1648 | if ((evolution_function_is_constant_p (chrec_a) | |
1649 | && evolution_function_is_univariate_p (chrec_b)) | |
1650 | || (evolution_function_is_constant_p (chrec_b) | |
1651 | && evolution_function_is_univariate_p (chrec_a))) | |
1652 | return true; | |
b8698a0f | 1653 | |
56cf8686 SP |
1654 | if (evolution_function_is_univariate_p (chrec_a) |
1655 | && evolution_function_is_univariate_p (chrec_b)) | |
1656 | { | |
1657 | switch (TREE_CODE (chrec_a)) | |
1658 | { | |
1659 | case POLYNOMIAL_CHREC: | |
1660 | switch (TREE_CODE (chrec_b)) | |
1661 | { | |
1662 | case POLYNOMIAL_CHREC: | |
1663 | if (CHREC_VARIABLE (chrec_a) != CHREC_VARIABLE (chrec_b)) | |
1664 | return false; | |
b8698a0f | 1665 | |
56cf8686 SP |
1666 | default: |
1667 | return true; | |
1668 | } | |
b8698a0f | 1669 | |
56cf8686 SP |
1670 | default: |
1671 | return true; | |
1672 | } | |
1673 | } | |
b8698a0f | 1674 | |
56cf8686 SP |
1675 | return false; |
1676 | } | |
1677 | ||
d93817c4 ZD |
1678 | /* Creates a conflict function with N dimensions. The affine functions |
1679 | in each dimension follow. */ | |
1680 | ||
1681 | static conflict_function * | |
1682 | conflict_fn (unsigned n, ...) | |
1683 | { | |
1684 | unsigned i; | |
1685 | conflict_function *ret = XCNEW (conflict_function); | |
1686 | va_list ap; | |
1687 | ||
b39c6706 | 1688 | gcc_assert (0 < n && n <= MAX_DIM); |
c3284718 | 1689 | va_start (ap, n); |
b8698a0f | 1690 | |
d93817c4 ZD |
1691 | ret->n = n; |
1692 | for (i = 0; i < n; i++) | |
1693 | ret->fns[i] = va_arg (ap, affine_fn); | |
c3284718 | 1694 | va_end (ap); |
d93817c4 ZD |
1695 | |
1696 | return ret; | |
1697 | } | |
1698 | ||
1699 | /* Returns constant affine function with value CST. */ | |
1700 | ||
1701 | static affine_fn | |
1702 | affine_fn_cst (tree cst) | |
1703 | { | |
9771b263 DN |
1704 | affine_fn fn; |
1705 | fn.create (1); | |
1706 | fn.quick_push (cst); | |
d93817c4 ZD |
1707 | return fn; |
1708 | } | |
1709 | ||
1710 | /* Returns affine function with single variable, CST + COEF * x_DIM. */ | |
1711 | ||
1712 | static affine_fn | |
1713 | affine_fn_univar (tree cst, unsigned dim, tree coef) | |
1714 | { | |
9771b263 DN |
1715 | affine_fn fn; |
1716 | fn.create (dim + 1); | |
d93817c4 ZD |
1717 | unsigned i; |
1718 | ||
1719 | gcc_assert (dim > 0); | |
9771b263 | 1720 | fn.quick_push (cst); |
d93817c4 | 1721 | for (i = 1; i < dim; i++) |
9771b263 DN |
1722 | fn.quick_push (integer_zero_node); |
1723 | fn.quick_push (coef); | |
d93817c4 ZD |
1724 | return fn; |
1725 | } | |
1726 | ||
56cf8686 SP |
1727 | /* Analyze a ZIV (Zero Index Variable) subscript. *OVERLAPS_A and |
1728 | *OVERLAPS_B are initialized to the functions that describe the | |
1729 | relation between the elements accessed twice by CHREC_A and | |
1730 | CHREC_B. For k >= 0, the following property is verified: | |
1731 | ||
1732 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1733 | ||
b8698a0f L |
1734 | static void |
1735 | analyze_ziv_subscript (tree chrec_a, | |
1736 | tree chrec_b, | |
d93817c4 | 1737 | conflict_function **overlaps_a, |
b8698a0f | 1738 | conflict_function **overlaps_b, |
86df10e3 | 1739 | tree *last_conflicts) |
56cf8686 | 1740 | { |
33b30201 | 1741 | tree type, difference; |
0ff4040e | 1742 | dependence_stats.num_ziv++; |
b8698a0f | 1743 | |
56cf8686 SP |
1744 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1745 | fprintf (dump_file, "(analyze_ziv_subscript \n"); | |
33b30201 SP |
1746 | |
1747 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); | |
726a989a RB |
1748 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1749 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1750 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
b8698a0f | 1751 | |
56cf8686 SP |
1752 | switch (TREE_CODE (difference)) |
1753 | { | |
1754 | case INTEGER_CST: | |
1755 | if (integer_zerop (difference)) | |
1756 | { | |
1757 | /* The difference is equal to zero: the accessed index | |
1758 | overlaps for each iteration in the loop. */ | |
d93817c4 ZD |
1759 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
1760 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 | 1761 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1762 | dependence_stats.num_ziv_dependent++; |
56cf8686 SP |
1763 | } |
1764 | else | |
1765 | { | |
1766 | /* The accesses do not overlap. */ | |
d93817c4 ZD |
1767 | *overlaps_a = conflict_fn_no_dependence (); |
1768 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 1769 | *last_conflicts = integer_zero_node; |
0ff4040e | 1770 | dependence_stats.num_ziv_independent++; |
56cf8686 SP |
1771 | } |
1772 | break; | |
b8698a0f | 1773 | |
56cf8686 | 1774 | default: |
b8698a0f | 1775 | /* We're not sure whether the indexes overlap. For the moment, |
56cf8686 | 1776 | conservatively answer "don't know". */ |
0ff4040e SP |
1777 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1778 | fprintf (dump_file, "ziv test failed: difference is non-integer.\n"); | |
1779 | ||
d93817c4 ZD |
1780 | *overlaps_a = conflict_fn_not_known (); |
1781 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1782 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1783 | dependence_stats.num_ziv_unimplemented++; |
56cf8686 SP |
1784 | break; |
1785 | } | |
b8698a0f | 1786 | |
56cf8686 SP |
1787 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1788 | fprintf (dump_file, ")\n"); | |
1789 | } | |
1790 | ||
b4a9343c | 1791 | /* Similar to max_stmt_executions_int, but returns the bound as a tree, |
4839cb59 | 1792 | and only if it fits to the int type. If this is not the case, or the |
b4a9343c | 1793 | bound on the number of iterations of LOOP could not be derived, returns |
4839cb59 ZD |
1794 | chrec_dont_know. */ |
1795 | ||
1796 | static tree | |
b4a9343c | 1797 | max_stmt_executions_tree (struct loop *loop) |
4839cb59 | 1798 | { |
807e902e | 1799 | widest_int nit; |
4839cb59 | 1800 | |
652c4c71 | 1801 | if (!max_stmt_executions (loop, &nit)) |
4839cb59 ZD |
1802 | return chrec_dont_know; |
1803 | ||
807e902e | 1804 | if (!wi::fits_to_tree_p (nit, unsigned_type_node)) |
4839cb59 ZD |
1805 | return chrec_dont_know; |
1806 | ||
807e902e | 1807 | return wide_int_to_tree (unsigned_type_node, nit); |
4839cb59 ZD |
1808 | } |
1809 | ||
5f1fab58 RG |
1810 | /* Determine whether the CHREC is always positive/negative. If the expression |
1811 | cannot be statically analyzed, return false, otherwise set the answer into | |
1812 | VALUE. */ | |
1813 | ||
1814 | static bool | |
1815 | chrec_is_positive (tree chrec, bool *value) | |
1816 | { | |
1817 | bool value0, value1, value2; | |
1818 | tree end_value, nb_iter; | |
1819 | ||
1820 | switch (TREE_CODE (chrec)) | |
1821 | { | |
1822 | case POLYNOMIAL_CHREC: | |
1823 | if (!chrec_is_positive (CHREC_LEFT (chrec), &value0) | |
1824 | || !chrec_is_positive (CHREC_RIGHT (chrec), &value1)) | |
1825 | return false; | |
1826 | ||
1827 | /* FIXME -- overflows. */ | |
1828 | if (value0 == value1) | |
1829 | { | |
1830 | *value = value0; | |
1831 | return true; | |
1832 | } | |
1833 | ||
1834 | /* Otherwise the chrec is under the form: "{-197, +, 2}_1", | |
1835 | and the proof consists in showing that the sign never | |
1836 | changes during the execution of the loop, from 0 to | |
1837 | loop->nb_iterations. */ | |
1838 | if (!evolution_function_is_affine_p (chrec)) | |
1839 | return false; | |
1840 | ||
1841 | nb_iter = number_of_latch_executions (get_chrec_loop (chrec)); | |
1842 | if (chrec_contains_undetermined (nb_iter)) | |
1843 | return false; | |
1844 | ||
1845 | #if 0 | |
1846 | /* TODO -- If the test is after the exit, we may decrease the number of | |
1847 | iterations by one. */ | |
1848 | if (after_exit) | |
1849 | nb_iter = chrec_fold_minus (type, nb_iter, build_int_cst (type, 1)); | |
1850 | #endif | |
1851 | ||
1852 | end_value = chrec_apply (CHREC_VARIABLE (chrec), chrec, nb_iter); | |
1853 | ||
1854 | if (!chrec_is_positive (end_value, &value2)) | |
1855 | return false; | |
1856 | ||
1857 | *value = value0; | |
1858 | return value0 == value1; | |
1859 | ||
1860 | case INTEGER_CST: | |
1861 | switch (tree_int_cst_sgn (chrec)) | |
1862 | { | |
1863 | case -1: | |
1864 | *value = false; | |
1865 | break; | |
1866 | case 1: | |
1867 | *value = true; | |
1868 | break; | |
1869 | default: | |
1870 | return false; | |
1871 | } | |
1872 | return true; | |
1873 | ||
1874 | default: | |
1875 | return false; | |
1876 | } | |
1877 | } | |
1878 | ||
1879 | ||
56cf8686 SP |
1880 | /* Analyze a SIV (Single Index Variable) subscript where CHREC_A is a |
1881 | constant, and CHREC_B is an affine function. *OVERLAPS_A and | |
1882 | *OVERLAPS_B are initialized to the functions that describe the | |
1883 | relation between the elements accessed twice by CHREC_A and | |
1884 | CHREC_B. For k >= 0, the following property is verified: | |
1885 | ||
1886 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
1887 | ||
1888 | static void | |
b8698a0f | 1889 | analyze_siv_subscript_cst_affine (tree chrec_a, |
56cf8686 | 1890 | tree chrec_b, |
b8698a0f L |
1891 | conflict_function **overlaps_a, |
1892 | conflict_function **overlaps_b, | |
86df10e3 | 1893 | tree *last_conflicts) |
56cf8686 SP |
1894 | { |
1895 | bool value0, value1, value2; | |
33b30201 | 1896 | tree type, difference, tmp; |
e2157b49 | 1897 | |
33b30201 | 1898 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
1899 | chrec_a = chrec_convert (type, chrec_a, NULL); |
1900 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 1901 | difference = chrec_fold_minus (type, initial_condition (chrec_b), chrec_a); |
b8698a0f | 1902 | |
5f1fab58 RG |
1903 | /* Special case overlap in the first iteration. */ |
1904 | if (integer_zerop (difference)) | |
1905 | { | |
1906 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
1907 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
1908 | *last_conflicts = integer_one_node; | |
1909 | return; | |
1910 | } | |
1911 | ||
56cf8686 SP |
1912 | if (!chrec_is_positive (initial_condition (difference), &value0)) |
1913 | { | |
0ff4040e | 1914 | if (dump_file && (dump_flags & TDF_DETAILS)) |
b8698a0f | 1915 | fprintf (dump_file, "siv test failed: chrec is not positive.\n"); |
0ff4040e SP |
1916 | |
1917 | dependence_stats.num_siv_unimplemented++; | |
d93817c4 ZD |
1918 | *overlaps_a = conflict_fn_not_known (); |
1919 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 1920 | *last_conflicts = chrec_dont_know; |
56cf8686 SP |
1921 | return; |
1922 | } | |
1923 | else | |
1924 | { | |
1925 | if (value0 == false) | |
1926 | { | |
1927 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value1)) | |
1928 | { | |
0ff4040e SP |
1929 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1930 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
1931 | ||
d93817c4 | 1932 | *overlaps_a = conflict_fn_not_known (); |
b8698a0f | 1933 | *overlaps_b = conflict_fn_not_known (); |
86df10e3 | 1934 | *last_conflicts = chrec_dont_know; |
0ff4040e | 1935 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
1936 | return; |
1937 | } | |
1938 | else | |
1939 | { | |
1940 | if (value1 == true) | |
1941 | { | |
b8698a0f | 1942 | /* Example: |
56cf8686 SP |
1943 | chrec_a = 12 |
1944 | chrec_b = {10, +, 1} | |
1945 | */ | |
b8698a0f | 1946 | |
f457cf40 | 1947 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 1948 | { |
4839cb59 ZD |
1949 | HOST_WIDE_INT numiter; |
1950 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 1951 | |
d93817c4 | 1952 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 SP |
1953 | tmp = fold_build2 (EXACT_DIV_EXPR, type, |
1954 | fold_build1 (ABS_EXPR, type, difference), | |
d93817c4 ZD |
1955 | CHREC_RIGHT (chrec_b)); |
1956 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 1957 | *last_conflicts = integer_one_node; |
b8698a0f | 1958 | |
416f403e DB |
1959 | |
1960 | /* Perform weak-zero siv test to see if overlap is | |
1961 | outside the loop bounds. */ | |
652c4c71 | 1962 | numiter = max_stmt_executions_int (loop); |
416f403e | 1963 | |
4839cb59 ZD |
1964 | if (numiter >= 0 |
1965 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 1966 | { |
d93817c4 ZD |
1967 | free_conflict_function (*overlaps_a); |
1968 | free_conflict_function (*overlaps_b); | |
1969 | *overlaps_a = conflict_fn_no_dependence (); | |
1970 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 1971 | *last_conflicts = integer_zero_node; |
0ff4040e | 1972 | dependence_stats.num_siv_independent++; |
416f403e | 1973 | return; |
b8698a0f | 1974 | } |
0ff4040e | 1975 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
1976 | return; |
1977 | } | |
b8698a0f | 1978 | |
f457cf40 | 1979 | /* When the step does not divide the difference, there are |
56cf8686 SP |
1980 | no overlaps. */ |
1981 | else | |
1982 | { | |
d93817c4 | 1983 | *overlaps_a = conflict_fn_no_dependence (); |
b8698a0f | 1984 | *overlaps_b = conflict_fn_no_dependence (); |
86df10e3 | 1985 | *last_conflicts = integer_zero_node; |
0ff4040e | 1986 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
1987 | return; |
1988 | } | |
1989 | } | |
b8698a0f | 1990 | |
56cf8686 SP |
1991 | else |
1992 | { | |
b8698a0f | 1993 | /* Example: |
56cf8686 SP |
1994 | chrec_a = 12 |
1995 | chrec_b = {10, +, -1} | |
b8698a0f | 1996 | |
56cf8686 | 1997 | In this case, chrec_a will not overlap with chrec_b. */ |
d93817c4 ZD |
1998 | *overlaps_a = conflict_fn_no_dependence (); |
1999 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2000 | *last_conflicts = integer_zero_node; |
0ff4040e | 2001 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
2002 | return; |
2003 | } | |
2004 | } | |
2005 | } | |
b8698a0f | 2006 | else |
56cf8686 SP |
2007 | { |
2008 | if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value2)) | |
2009 | { | |
0ff4040e SP |
2010 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2011 | fprintf (dump_file, "siv test failed: chrec not positive.\n"); | |
2012 | ||
d93817c4 | 2013 | *overlaps_a = conflict_fn_not_known (); |
b8698a0f | 2014 | *overlaps_b = conflict_fn_not_known (); |
86df10e3 | 2015 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2016 | dependence_stats.num_siv_unimplemented++; |
56cf8686 SP |
2017 | return; |
2018 | } | |
2019 | else | |
2020 | { | |
2021 | if (value2 == false) | |
2022 | { | |
b8698a0f | 2023 | /* Example: |
56cf8686 SP |
2024 | chrec_a = 3 |
2025 | chrec_b = {10, +, -1} | |
2026 | */ | |
f457cf40 | 2027 | if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) |
56cf8686 | 2028 | { |
4839cb59 ZD |
2029 | HOST_WIDE_INT numiter; |
2030 | struct loop *loop = get_chrec_loop (chrec_b); | |
416f403e | 2031 | |
d93817c4 | 2032 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
33b30201 | 2033 | tmp = fold_build2 (EXACT_DIV_EXPR, type, difference, |
d93817c4 ZD |
2034 | CHREC_RIGHT (chrec_b)); |
2035 | *overlaps_b = conflict_fn (1, affine_fn_cst (tmp)); | |
86df10e3 | 2036 | *last_conflicts = integer_one_node; |
416f403e DB |
2037 | |
2038 | /* Perform weak-zero siv test to see if overlap is | |
2039 | outside the loop bounds. */ | |
652c4c71 | 2040 | numiter = max_stmt_executions_int (loop); |
416f403e | 2041 | |
4839cb59 ZD |
2042 | if (numiter >= 0 |
2043 | && compare_tree_int (tmp, numiter) > 0) | |
416f403e | 2044 | { |
d93817c4 ZD |
2045 | free_conflict_function (*overlaps_a); |
2046 | free_conflict_function (*overlaps_b); | |
2047 | *overlaps_a = conflict_fn_no_dependence (); | |
2048 | *overlaps_b = conflict_fn_no_dependence (); | |
416f403e | 2049 | *last_conflicts = integer_zero_node; |
0ff4040e | 2050 | dependence_stats.num_siv_independent++; |
416f403e | 2051 | return; |
b8698a0f | 2052 | } |
0ff4040e | 2053 | dependence_stats.num_siv_dependent++; |
56cf8686 SP |
2054 | return; |
2055 | } | |
b8698a0f | 2056 | |
4286d8ce | 2057 | /* When the step does not divide the difference, there |
56cf8686 SP |
2058 | are no overlaps. */ |
2059 | else | |
2060 | { | |
d93817c4 | 2061 | *overlaps_a = conflict_fn_no_dependence (); |
b8698a0f | 2062 | *overlaps_b = conflict_fn_no_dependence (); |
86df10e3 | 2063 | *last_conflicts = integer_zero_node; |
0ff4040e | 2064 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
2065 | return; |
2066 | } | |
2067 | } | |
2068 | else | |
2069 | { | |
b8698a0f L |
2070 | /* Example: |
2071 | chrec_a = 3 | |
56cf8686 | 2072 | chrec_b = {4, +, 1} |
b8698a0f | 2073 | |
56cf8686 | 2074 | In this case, chrec_a will not overlap with chrec_b. */ |
d93817c4 ZD |
2075 | *overlaps_a = conflict_fn_no_dependence (); |
2076 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2077 | *last_conflicts = integer_zero_node; |
0ff4040e | 2078 | dependence_stats.num_siv_independent++; |
56cf8686 SP |
2079 | return; |
2080 | } | |
2081 | } | |
2082 | } | |
2083 | } | |
2084 | } | |
2085 | ||
50300b4c | 2086 | /* Helper recursive function for initializing the matrix A. Returns |
86df10e3 | 2087 | the initial value of CHREC. */ |
56cf8686 | 2088 | |
5b78fc3e | 2089 | static tree |
86df10e3 SP |
2090 | initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) |
2091 | { | |
2092 | gcc_assert (chrec); | |
2093 | ||
5b78fc3e JS |
2094 | switch (TREE_CODE (chrec)) |
2095 | { | |
2096 | case POLYNOMIAL_CHREC: | |
2097 | gcc_assert (TREE_CODE (CHREC_RIGHT (chrec)) == INTEGER_CST); | |
2098 | ||
2099 | A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); | |
2100 | return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); | |
2101 | ||
2102 | case PLUS_EXPR: | |
2103 | case MULT_EXPR: | |
2104 | case MINUS_EXPR: | |
2105 | { | |
2106 | tree op0 = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
2107 | tree op1 = initialize_matrix_A (A, TREE_OPERAND (chrec, 1), index, mult); | |
2108 | ||
2109 | return chrec_fold_op (TREE_CODE (chrec), chrec_type (chrec), op0, op1); | |
2110 | } | |
2111 | ||
625a9766 | 2112 | CASE_CONVERT: |
5b78fc3e JS |
2113 | { |
2114 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
726a989a | 2115 | return chrec_convert (chrec_type (chrec), op, NULL); |
5b78fc3e JS |
2116 | } |
2117 | ||
418df9d7 JJ |
2118 | case BIT_NOT_EXPR: |
2119 | { | |
2120 | /* Handle ~X as -1 - X. */ | |
2121 | tree op = initialize_matrix_A (A, TREE_OPERAND (chrec, 0), index, mult); | |
2122 | return chrec_fold_op (MINUS_EXPR, chrec_type (chrec), | |
2123 | build_int_cst (TREE_TYPE (chrec), -1), op); | |
2124 | } | |
2125 | ||
5b78fc3e JS |
2126 | case INTEGER_CST: |
2127 | return chrec; | |
a1a5996d | 2128 | |
5b78fc3e JS |
2129 | default: |
2130 | gcc_unreachable (); | |
2131 | return NULL_TREE; | |
2132 | } | |
86df10e3 SP |
2133 | } |
2134 | ||
2135 | #define FLOOR_DIV(x,y) ((x) / (y)) | |
2136 | ||
b8698a0f | 2137 | /* Solves the special case of the Diophantine equation: |
86df10e3 SP |
2138 | | {0, +, STEP_A}_x (OVERLAPS_A) = {0, +, STEP_B}_y (OVERLAPS_B) |
2139 | ||
2140 | Computes the descriptions OVERLAPS_A and OVERLAPS_B. NITER is the | |
2141 | number of iterations that loops X and Y run. The overlaps will be | |
2142 | constructed as evolutions in dimension DIM. */ | |
56cf8686 SP |
2143 | |
2144 | static void | |
b8698a0f | 2145 | compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b, |
d93817c4 | 2146 | affine_fn *overlaps_a, |
b8698a0f | 2147 | affine_fn *overlaps_b, |
86df10e3 SP |
2148 | tree *last_conflicts, int dim) |
2149 | { | |
2150 | if (((step_a > 0 && step_b > 0) | |
2151 | || (step_a < 0 && step_b < 0))) | |
2152 | { | |
2153 | int step_overlaps_a, step_overlaps_b; | |
2154 | int gcd_steps_a_b, last_conflict, tau2; | |
2155 | ||
2156 | gcd_steps_a_b = gcd (step_a, step_b); | |
2157 | step_overlaps_a = step_b / gcd_steps_a_b; | |
2158 | step_overlaps_b = step_a / gcd_steps_a_b; | |
2159 | ||
2c26cbfd SP |
2160 | if (niter > 0) |
2161 | { | |
2162 | tau2 = FLOOR_DIV (niter, step_overlaps_a); | |
2163 | tau2 = MIN (tau2, FLOOR_DIV (niter, step_overlaps_b)); | |
2164 | last_conflict = tau2; | |
2165 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); | |
2166 | } | |
2167 | else | |
2168 | *last_conflicts = chrec_dont_know; | |
86df10e3 | 2169 | |
b8698a0f | 2170 | *overlaps_a = affine_fn_univar (integer_zero_node, dim, |
d93817c4 ZD |
2171 | build_int_cst (NULL_TREE, |
2172 | step_overlaps_a)); | |
b8698a0f L |
2173 | *overlaps_b = affine_fn_univar (integer_zero_node, dim, |
2174 | build_int_cst (NULL_TREE, | |
d93817c4 | 2175 | step_overlaps_b)); |
86df10e3 SP |
2176 | } |
2177 | ||
2178 | else | |
2179 | { | |
d93817c4 ZD |
2180 | *overlaps_a = affine_fn_cst (integer_zero_node); |
2181 | *overlaps_b = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
2182 | *last_conflicts = integer_zero_node; |
2183 | } | |
2184 | } | |
2185 | ||
86df10e3 SP |
2186 | /* Solves the special case of a Diophantine equation where CHREC_A is |
2187 | an affine bivariate function, and CHREC_B is an affine univariate | |
b8698a0f | 2188 | function. For example, |
86df10e3 SP |
2189 | |
2190 | | {{0, +, 1}_x, +, 1335}_y = {0, +, 1336}_z | |
b8698a0f L |
2191 | |
2192 | has the following overlapping functions: | |
86df10e3 SP |
2193 | |
2194 | | x (t, u, v) = {{0, +, 1336}_t, +, 1}_v | |
2195 | | y (t, u, v) = {{0, +, 1336}_u, +, 1}_v | |
2196 | | z (t, u, v) = {{{0, +, 1}_t, +, 1335}_u, +, 1}_v | |
2197 | ||
35fd3193 | 2198 | FORNOW: This is a specialized implementation for a case occurring in |
86df10e3 SP |
2199 | a common benchmark. Implement the general algorithm. */ |
2200 | ||
2201 | static void | |
b8698a0f | 2202 | compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b, |
d93817c4 | 2203 | conflict_function **overlaps_a, |
b8698a0f | 2204 | conflict_function **overlaps_b, |
86df10e3 | 2205 | tree *last_conflicts) |
56cf8686 | 2206 | { |
86df10e3 SP |
2207 | bool xz_p, yz_p, xyz_p; |
2208 | int step_x, step_y, step_z; | |
4839cb59 | 2209 | HOST_WIDE_INT niter_x, niter_y, niter_z, niter; |
d93817c4 ZD |
2210 | affine_fn overlaps_a_xz, overlaps_b_xz; |
2211 | affine_fn overlaps_a_yz, overlaps_b_yz; | |
2212 | affine_fn overlaps_a_xyz, overlaps_b_xyz; | |
2213 | affine_fn ova1, ova2, ovb; | |
2214 | tree last_conflicts_xz, last_conflicts_yz, last_conflicts_xyz; | |
86df10e3 | 2215 | |
6b6fa4e9 SP |
2216 | step_x = int_cst_value (CHREC_RIGHT (CHREC_LEFT (chrec_a))); |
2217 | step_y = int_cst_value (CHREC_RIGHT (chrec_a)); | |
2218 | step_z = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2219 | |
652c4c71 RG |
2220 | niter_x = max_stmt_executions_int (get_chrec_loop (CHREC_LEFT (chrec_a))); |
2221 | niter_y = max_stmt_executions_int (get_chrec_loop (chrec_a)); | |
2222 | niter_z = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
b8698a0f | 2223 | |
4839cb59 | 2224 | if (niter_x < 0 || niter_y < 0 || niter_z < 0) |
86df10e3 | 2225 | { |
0ff4040e SP |
2226 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2227 | fprintf (dump_file, "overlap steps test failed: no iteration counts.\n"); | |
b8698a0f | 2228 | |
d93817c4 ZD |
2229 | *overlaps_a = conflict_fn_not_known (); |
2230 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2231 | *last_conflicts = chrec_dont_know; |
2232 | return; | |
2233 | } | |
2234 | ||
86df10e3 SP |
2235 | niter = MIN (niter_x, niter_z); |
2236 | compute_overlap_steps_for_affine_univar (niter, step_x, step_z, | |
2237 | &overlaps_a_xz, | |
2238 | &overlaps_b_xz, | |
2239 | &last_conflicts_xz, 1); | |
2240 | niter = MIN (niter_y, niter_z); | |
2241 | compute_overlap_steps_for_affine_univar (niter, step_y, step_z, | |
2242 | &overlaps_a_yz, | |
2243 | &overlaps_b_yz, | |
2244 | &last_conflicts_yz, 2); | |
2245 | niter = MIN (niter_x, niter_z); | |
2246 | niter = MIN (niter_y, niter); | |
2247 | compute_overlap_steps_for_affine_univar (niter, step_x + step_y, step_z, | |
2248 | &overlaps_a_xyz, | |
2249 | &overlaps_b_xyz, | |
2250 | &last_conflicts_xyz, 3); | |
2251 | ||
2252 | xz_p = !integer_zerop (last_conflicts_xz); | |
2253 | yz_p = !integer_zerop (last_conflicts_yz); | |
2254 | xyz_p = !integer_zerop (last_conflicts_xyz); | |
2255 | ||
2256 | if (xz_p || yz_p || xyz_p) | |
2257 | { | |
d93817c4 ZD |
2258 | ova1 = affine_fn_cst (integer_zero_node); |
2259 | ova2 = affine_fn_cst (integer_zero_node); | |
2260 | ovb = affine_fn_cst (integer_zero_node); | |
86df10e3 SP |
2261 | if (xz_p) |
2262 | { | |
d93817c4 ZD |
2263 | affine_fn t0 = ova1; |
2264 | affine_fn t2 = ovb; | |
2265 | ||
2266 | ova1 = affine_fn_plus (ova1, overlaps_a_xz); | |
2267 | ovb = affine_fn_plus (ovb, overlaps_b_xz); | |
2268 | affine_fn_free (t0); | |
2269 | affine_fn_free (t2); | |
86df10e3 SP |
2270 | *last_conflicts = last_conflicts_xz; |
2271 | } | |
2272 | if (yz_p) | |
2273 | { | |
d93817c4 ZD |
2274 | affine_fn t0 = ova2; |
2275 | affine_fn t2 = ovb; | |
2276 | ||
2277 | ova2 = affine_fn_plus (ova2, overlaps_a_yz); | |
2278 | ovb = affine_fn_plus (ovb, overlaps_b_yz); | |
2279 | affine_fn_free (t0); | |
2280 | affine_fn_free (t2); | |
86df10e3 SP |
2281 | *last_conflicts = last_conflicts_yz; |
2282 | } | |
2283 | if (xyz_p) | |
2284 | { | |
d93817c4 ZD |
2285 | affine_fn t0 = ova1; |
2286 | affine_fn t2 = ova2; | |
2287 | affine_fn t4 = ovb; | |
2288 | ||
2289 | ova1 = affine_fn_plus (ova1, overlaps_a_xyz); | |
2290 | ova2 = affine_fn_plus (ova2, overlaps_a_xyz); | |
2291 | ovb = affine_fn_plus (ovb, overlaps_b_xyz); | |
2292 | affine_fn_free (t0); | |
2293 | affine_fn_free (t2); | |
2294 | affine_fn_free (t4); | |
86df10e3 SP |
2295 | *last_conflicts = last_conflicts_xyz; |
2296 | } | |
d93817c4 ZD |
2297 | *overlaps_a = conflict_fn (2, ova1, ova2); |
2298 | *overlaps_b = conflict_fn (1, ovb); | |
86df10e3 SP |
2299 | } |
2300 | else | |
2301 | { | |
d93817c4 ZD |
2302 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2303 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
86df10e3 SP |
2304 | *last_conflicts = integer_zero_node; |
2305 | } | |
d93817c4 ZD |
2306 | |
2307 | affine_fn_free (overlaps_a_xz); | |
2308 | affine_fn_free (overlaps_b_xz); | |
2309 | affine_fn_free (overlaps_a_yz); | |
2310 | affine_fn_free (overlaps_b_yz); | |
2311 | affine_fn_free (overlaps_a_xyz); | |
2312 | affine_fn_free (overlaps_b_xyz); | |
56cf8686 SP |
2313 | } |
2314 | ||
b305e3da SP |
2315 | /* Copy the elements of vector VEC1 with length SIZE to VEC2. */ |
2316 | ||
2317 | static void | |
2318 | lambda_vector_copy (lambda_vector vec1, lambda_vector vec2, | |
2319 | int size) | |
2320 | { | |
2321 | memcpy (vec2, vec1, size * sizeof (*vec1)); | |
2322 | } | |
2323 | ||
2324 | /* Copy the elements of M x N matrix MAT1 to MAT2. */ | |
2325 | ||
2326 | static void | |
2327 | lambda_matrix_copy (lambda_matrix mat1, lambda_matrix mat2, | |
2328 | int m, int n) | |
2329 | { | |
2330 | int i; | |
2331 | ||
2332 | for (i = 0; i < m; i++) | |
2333 | lambda_vector_copy (mat1[i], mat2[i], n); | |
2334 | } | |
2335 | ||
2336 | /* Store the N x N identity matrix in MAT. */ | |
2337 | ||
2338 | static void | |
2339 | lambda_matrix_id (lambda_matrix mat, int size) | |
2340 | { | |
2341 | int i, j; | |
2342 | ||
2343 | for (i = 0; i < size; i++) | |
2344 | for (j = 0; j < size; j++) | |
2345 | mat[i][j] = (i == j) ? 1 : 0; | |
2346 | } | |
2347 | ||
2348 | /* Return the first nonzero element of vector VEC1 between START and N. | |
2349 | We must have START <= N. Returns N if VEC1 is the zero vector. */ | |
2350 | ||
2351 | static int | |
2352 | lambda_vector_first_nz (lambda_vector vec1, int n, int start) | |
2353 | { | |
2354 | int j = start; | |
2355 | while (j < n && vec1[j] == 0) | |
2356 | j++; | |
2357 | return j; | |
2358 | } | |
2359 | ||
2360 | /* Add a multiple of row R1 of matrix MAT with N columns to row R2: | |
2361 | R2 = R2 + CONST1 * R1. */ | |
2362 | ||
2363 | static void | |
2364 | lambda_matrix_row_add (lambda_matrix mat, int n, int r1, int r2, int const1) | |
2365 | { | |
2366 | int i; | |
2367 | ||
2368 | if (const1 == 0) | |
2369 | return; | |
2370 | ||
2371 | for (i = 0; i < n; i++) | |
2372 | mat[r2][i] += const1 * mat[r1][i]; | |
2373 | } | |
2374 | ||
2375 | /* Swap rows R1 and R2 in matrix MAT. */ | |
2376 | ||
2377 | static void | |
2378 | lambda_matrix_row_exchange (lambda_matrix mat, int r1, int r2) | |
2379 | { | |
2380 | lambda_vector row; | |
2381 | ||
2382 | row = mat[r1]; | |
2383 | mat[r1] = mat[r2]; | |
2384 | mat[r2] = row; | |
2385 | } | |
2386 | ||
2387 | /* Multiply vector VEC1 of length SIZE by a constant CONST1, | |
2388 | and store the result in VEC2. */ | |
2389 | ||
2390 | static void | |
2391 | lambda_vector_mult_const (lambda_vector vec1, lambda_vector vec2, | |
2392 | int size, int const1) | |
2393 | { | |
2394 | int i; | |
2395 | ||
2396 | if (const1 == 0) | |
2397 | lambda_vector_clear (vec2, size); | |
2398 | else | |
2399 | for (i = 0; i < size; i++) | |
2400 | vec2[i] = const1 * vec1[i]; | |
2401 | } | |
2402 | ||
2403 | /* Negate vector VEC1 with length SIZE and store it in VEC2. */ | |
2404 | ||
2405 | static void | |
2406 | lambda_vector_negate (lambda_vector vec1, lambda_vector vec2, | |
2407 | int size) | |
2408 | { | |
2409 | lambda_vector_mult_const (vec1, vec2, size, -1); | |
2410 | } | |
2411 | ||
2412 | /* Negate row R1 of matrix MAT which has N columns. */ | |
2413 | ||
2414 | static void | |
2415 | lambda_matrix_row_negate (lambda_matrix mat, int n, int r1) | |
2416 | { | |
2417 | lambda_vector_negate (mat[r1], mat[r1], n); | |
2418 | } | |
2419 | ||
2420 | /* Return true if two vectors are equal. */ | |
2421 | ||
2422 | static bool | |
2423 | lambda_vector_equal (lambda_vector vec1, lambda_vector vec2, int size) | |
2424 | { | |
2425 | int i; | |
2426 | for (i = 0; i < size; i++) | |
2427 | if (vec1[i] != vec2[i]) | |
2428 | return false; | |
2429 | return true; | |
2430 | } | |
2431 | ||
2432 | /* Given an M x N integer matrix A, this function determines an M x | |
2433 | M unimodular matrix U, and an M x N echelon matrix S such that | |
2434 | "U.A = S". This decomposition is also known as "right Hermite". | |
2435 | ||
2436 | Ref: Algorithm 2.1 page 33 in "Loop Transformations for | |
2437 | Restructuring Compilers" Utpal Banerjee. */ | |
2438 | ||
2439 | static void | |
2440 | lambda_matrix_right_hermite (lambda_matrix A, int m, int n, | |
2441 | lambda_matrix S, lambda_matrix U) | |
2442 | { | |
2443 | int i, j, i0 = 0; | |
2444 | ||
2445 | lambda_matrix_copy (A, S, m, n); | |
2446 | lambda_matrix_id (U, m); | |
2447 | ||
2448 | for (j = 0; j < n; j++) | |
2449 | { | |
2450 | if (lambda_vector_first_nz (S[j], m, i0) < m) | |
2451 | { | |
2452 | ++i0; | |
2453 | for (i = m - 1; i >= i0; i--) | |
2454 | { | |
2455 | while (S[i][j] != 0) | |
2456 | { | |
2457 | int sigma, factor, a, b; | |
2458 | ||
2459 | a = S[i-1][j]; | |
2460 | b = S[i][j]; | |
2461 | sigma = (a * b < 0) ? -1: 1; | |
2462 | a = abs (a); | |
2463 | b = abs (b); | |
2464 | factor = sigma * (a / b); | |
2465 | ||
2466 | lambda_matrix_row_add (S, n, i, i-1, -factor); | |
2467 | lambda_matrix_row_exchange (S, i, i-1); | |
2468 | ||
2469 | lambda_matrix_row_add (U, m, i, i-1, -factor); | |
2470 | lambda_matrix_row_exchange (U, i, i-1); | |
2471 | } | |
2472 | } | |
2473 | } | |
2474 | } | |
2475 | } | |
2476 | ||
56cf8686 | 2477 | /* Determines the overlapping elements due to accesses CHREC_A and |
0ff4040e SP |
2478 | CHREC_B, that are affine functions. This function cannot handle |
2479 | symbolic evolution functions, ie. when initial conditions are | |
2480 | parameters, because it uses lambda matrices of integers. */ | |
56cf8686 SP |
2481 | |
2482 | static void | |
b8698a0f | 2483 | analyze_subscript_affine_affine (tree chrec_a, |
56cf8686 | 2484 | tree chrec_b, |
b8698a0f L |
2485 | conflict_function **overlaps_a, |
2486 | conflict_function **overlaps_b, | |
86df10e3 | 2487 | tree *last_conflicts) |
56cf8686 | 2488 | { |
86df10e3 | 2489 | unsigned nb_vars_a, nb_vars_b, dim; |
fd727b34 | 2490 | HOST_WIDE_INT init_a, init_b, gamma, gcd_alpha_beta; |
86df10e3 | 2491 | lambda_matrix A, U, S; |
f873b205 | 2492 | struct obstack scratch_obstack; |
86df10e3 | 2493 | |
e2157b49 | 2494 | if (eq_evolutions_p (chrec_a, chrec_b)) |
416f403e | 2495 | { |
e2157b49 SP |
2496 | /* The accessed index overlaps for each iteration in the |
2497 | loop. */ | |
d93817c4 ZD |
2498 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2499 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
416f403e DB |
2500 | *last_conflicts = chrec_dont_know; |
2501 | return; | |
2502 | } | |
56cf8686 SP |
2503 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2504 | fprintf (dump_file, "(analyze_subscript_affine_affine \n"); | |
b8698a0f | 2505 | |
56cf8686 SP |
2506 | /* For determining the initial intersection, we have to solve a |
2507 | Diophantine equation. This is the most time consuming part. | |
b8698a0f | 2508 | |
56cf8686 SP |
2509 | For answering to the question: "Is there a dependence?" we have |
2510 | to prove that there exists a solution to the Diophantine | |
2511 | equation, and that the solution is in the iteration domain, | |
89dbed81 | 2512 | i.e. the solution is positive or zero, and that the solution |
56cf8686 SP |
2513 | happens before the upper bound loop.nb_iterations. Otherwise |
2514 | there is no dependence. This function outputs a description of | |
2515 | the iterations that hold the intersections. */ | |
2516 | ||
86df10e3 SP |
2517 | nb_vars_a = nb_vars_in_chrec (chrec_a); |
2518 | nb_vars_b = nb_vars_in_chrec (chrec_b); | |
2519 | ||
f873b205 LB |
2520 | gcc_obstack_init (&scratch_obstack); |
2521 | ||
86df10e3 | 2522 | dim = nb_vars_a + nb_vars_b; |
f873b205 LB |
2523 | U = lambda_matrix_new (dim, dim, &scratch_obstack); |
2524 | A = lambda_matrix_new (dim, 1, &scratch_obstack); | |
2525 | S = lambda_matrix_new (dim, 1, &scratch_obstack); | |
86df10e3 | 2526 | |
5b78fc3e JS |
2527 | init_a = int_cst_value (initialize_matrix_A (A, chrec_a, 0, 1)); |
2528 | init_b = int_cst_value (initialize_matrix_A (A, chrec_b, nb_vars_a, -1)); | |
86df10e3 SP |
2529 | gamma = init_b - init_a; |
2530 | ||
2531 | /* Don't do all the hard work of solving the Diophantine equation | |
b8698a0f | 2532 | when we already know the solution: for example, |
86df10e3 SP |
2533 | | {3, +, 1}_1 |
2534 | | {3, +, 4}_2 | |
2535 | | gamma = 3 - 3 = 0. | |
b8698a0f | 2536 | Then the first overlap occurs during the first iterations: |
86df10e3 SP |
2537 | | {3, +, 1}_1 ({0, +, 4}_x) = {3, +, 4}_2 ({0, +, 1}_x) |
2538 | */ | |
2539 | if (gamma == 0) | |
56cf8686 | 2540 | { |
86df10e3 | 2541 | if (nb_vars_a == 1 && nb_vars_b == 1) |
56cf8686 | 2542 | { |
fd727b34 | 2543 | HOST_WIDE_INT step_a, step_b; |
4839cb59 | 2544 | HOST_WIDE_INT niter, niter_a, niter_b; |
d93817c4 | 2545 | affine_fn ova, ovb; |
86df10e3 | 2546 | |
652c4c71 RG |
2547 | niter_a = max_stmt_executions_int (get_chrec_loop (chrec_a)); |
2548 | niter_b = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
86df10e3 | 2549 | niter = MIN (niter_a, niter_b); |
6b6fa4e9 SP |
2550 | step_a = int_cst_value (CHREC_RIGHT (chrec_a)); |
2551 | step_b = int_cst_value (CHREC_RIGHT (chrec_b)); | |
86df10e3 | 2552 | |
b8698a0f L |
2553 | compute_overlap_steps_for_affine_univar (niter, step_a, step_b, |
2554 | &ova, &ovb, | |
86df10e3 | 2555 | last_conflicts, 1); |
d93817c4 ZD |
2556 | *overlaps_a = conflict_fn (1, ova); |
2557 | *overlaps_b = conflict_fn (1, ovb); | |
56cf8686 | 2558 | } |
86df10e3 SP |
2559 | |
2560 | else if (nb_vars_a == 2 && nb_vars_b == 1) | |
2561 | compute_overlap_steps_for_affine_1_2 | |
2562 | (chrec_a, chrec_b, overlaps_a, overlaps_b, last_conflicts); | |
2563 | ||
2564 | else if (nb_vars_a == 1 && nb_vars_b == 2) | |
2565 | compute_overlap_steps_for_affine_1_2 | |
2566 | (chrec_b, chrec_a, overlaps_b, overlaps_a, last_conflicts); | |
2567 | ||
2568 | else | |
56cf8686 | 2569 | { |
0ff4040e SP |
2570 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2571 | fprintf (dump_file, "affine-affine test failed: too many variables.\n"); | |
d93817c4 ZD |
2572 | *overlaps_a = conflict_fn_not_known (); |
2573 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2574 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2575 | } |
0ff4040e | 2576 | goto end_analyze_subs_aa; |
86df10e3 SP |
2577 | } |
2578 | ||
2579 | /* U.A = S */ | |
2580 | lambda_matrix_right_hermite (A, dim, 1, S, U); | |
2581 | ||
2582 | if (S[0][0] < 0) | |
2583 | { | |
2584 | S[0][0] *= -1; | |
2585 | lambda_matrix_row_negate (U, dim, 0); | |
2586 | } | |
2587 | gcd_alpha_beta = S[0][0]; | |
2588 | ||
ba42e045 SP |
2589 | /* Something went wrong: for example in {1, +, 0}_5 vs. {0, +, 0}_5, |
2590 | but that is a quite strange case. Instead of ICEing, answer | |
2591 | don't know. */ | |
2592 | if (gcd_alpha_beta == 0) | |
2593 | { | |
d93817c4 ZD |
2594 | *overlaps_a = conflict_fn_not_known (); |
2595 | *overlaps_b = conflict_fn_not_known (); | |
ba42e045 SP |
2596 | *last_conflicts = chrec_dont_know; |
2597 | goto end_analyze_subs_aa; | |
2598 | } | |
2599 | ||
86df10e3 SP |
2600 | /* The classic "gcd-test". */ |
2601 | if (!int_divides_p (gcd_alpha_beta, gamma)) | |
2602 | { | |
2603 | /* The "gcd-test" has determined that there is no integer | |
2604 | solution, i.e. there is no dependence. */ | |
d93817c4 ZD |
2605 | *overlaps_a = conflict_fn_no_dependence (); |
2606 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 SP |
2607 | *last_conflicts = integer_zero_node; |
2608 | } | |
2609 | ||
2610 | /* Both access functions are univariate. This includes SIV and MIV cases. */ | |
2611 | else if (nb_vars_a == 1 && nb_vars_b == 1) | |
2612 | { | |
2613 | /* Both functions should have the same evolution sign. */ | |
2614 | if (((A[0][0] > 0 && -A[1][0] > 0) | |
2615 | || (A[0][0] < 0 && -A[1][0] < 0))) | |
56cf8686 SP |
2616 | { |
2617 | /* The solutions are given by: | |
b8698a0f | 2618 | | |
86df10e3 SP |
2619 | | [GAMMA/GCD_ALPHA_BETA t].[u11 u12] = [x0] |
2620 | | [u21 u22] [y0] | |
b8698a0f | 2621 | |
56cf8686 | 2622 | For a given integer t. Using the following variables, |
b8698a0f | 2623 | |
56cf8686 SP |
2624 | | i0 = u11 * gamma / gcd_alpha_beta |
2625 | | j0 = u12 * gamma / gcd_alpha_beta | |
2626 | | i1 = u21 | |
2627 | | j1 = u22 | |
b8698a0f | 2628 | |
56cf8686 | 2629 | the solutions are: |
b8698a0f L |
2630 | |
2631 | | x0 = i0 + i1 * t, | |
86df10e3 | 2632 | | y0 = j0 + j1 * t. */ |
2c26cbfd | 2633 | HOST_WIDE_INT i0, j0, i1, j1; |
86df10e3 SP |
2634 | |
2635 | i0 = U[0][0] * gamma / gcd_alpha_beta; | |
2636 | j0 = U[0][1] * gamma / gcd_alpha_beta; | |
2637 | i1 = U[1][0]; | |
2638 | j1 = U[1][1]; | |
2639 | ||
2640 | if ((i1 == 0 && i0 < 0) | |
2641 | || (j1 == 0 && j0 < 0)) | |
56cf8686 | 2642 | { |
b8698a0f L |
2643 | /* There is no solution. |
2644 | FIXME: The case "i0 > nb_iterations, j0 > nb_iterations" | |
2645 | falls in here, but for the moment we don't look at the | |
56cf8686 | 2646 | upper bound of the iteration domain. */ |
d93817c4 ZD |
2647 | *overlaps_a = conflict_fn_no_dependence (); |
2648 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2649 | *last_conflicts = integer_zero_node; |
2c26cbfd | 2650 | goto end_analyze_subs_aa; |
86df10e3 SP |
2651 | } |
2652 | ||
2c26cbfd | 2653 | if (i1 > 0 && j1 > 0) |
56cf8686 | 2654 | { |
652c4c71 RG |
2655 | HOST_WIDE_INT niter_a |
2656 | = max_stmt_executions_int (get_chrec_loop (chrec_a)); | |
2657 | HOST_WIDE_INT niter_b | |
2658 | = max_stmt_executions_int (get_chrec_loop (chrec_b)); | |
2c26cbfd SP |
2659 | HOST_WIDE_INT niter = MIN (niter_a, niter_b); |
2660 | ||
2661 | /* (X0, Y0) is a solution of the Diophantine equation: | |
2662 | "chrec_a (X0) = chrec_b (Y0)". */ | |
2663 | HOST_WIDE_INT tau1 = MAX (CEIL (-i0, i1), | |
2664 | CEIL (-j0, j1)); | |
2665 | HOST_WIDE_INT x0 = i1 * tau1 + i0; | |
2666 | HOST_WIDE_INT y0 = j1 * tau1 + j0; | |
2667 | ||
2668 | /* (X1, Y1) is the smallest positive solution of the eq | |
2669 | "chrec_a (X1) = chrec_b (Y1)", i.e. this is where the | |
2670 | first conflict occurs. */ | |
2671 | HOST_WIDE_INT min_multiple = MIN (x0 / i1, y0 / j1); | |
2672 | HOST_WIDE_INT x1 = x0 - i1 * min_multiple; | |
2673 | HOST_WIDE_INT y1 = y0 - j1 * min_multiple; | |
2674 | ||
2675 | if (niter > 0) | |
56cf8686 | 2676 | { |
2c26cbfd SP |
2677 | HOST_WIDE_INT tau2 = MIN (FLOOR_DIV (niter - i0, i1), |
2678 | FLOOR_DIV (niter - j0, j1)); | |
2679 | HOST_WIDE_INT last_conflict = tau2 - (x1 - i0)/i1; | |
86df10e3 | 2680 | |
2c26cbfd SP |
2681 | /* If the overlap occurs outside of the bounds of the |
2682 | loop, there is no dependence. */ | |
9e517d61 | 2683 | if (x1 >= niter || y1 >= niter) |
56cf8686 | 2684 | { |
2c26cbfd SP |
2685 | *overlaps_a = conflict_fn_no_dependence (); |
2686 | *overlaps_b = conflict_fn_no_dependence (); | |
2687 | *last_conflicts = integer_zero_node; | |
2688 | goto end_analyze_subs_aa; | |
56cf8686 SP |
2689 | } |
2690 | else | |
2c26cbfd | 2691 | *last_conflicts = build_int_cst (NULL_TREE, last_conflict); |
56cf8686 | 2692 | } |
56cf8686 | 2693 | else |
2c26cbfd SP |
2694 | *last_conflicts = chrec_dont_know; |
2695 | ||
2696 | *overlaps_a | |
2697 | = conflict_fn (1, | |
2698 | affine_fn_univar (build_int_cst (NULL_TREE, x1), | |
2699 | 1, | |
2700 | build_int_cst (NULL_TREE, i1))); | |
2701 | *overlaps_b | |
2702 | = conflict_fn (1, | |
2703 | affine_fn_univar (build_int_cst (NULL_TREE, y1), | |
2704 | 1, | |
2705 | build_int_cst (NULL_TREE, j1))); | |
2706 | } | |
2707 | else | |
2708 | { | |
2709 | /* FIXME: For the moment, the upper bound of the | |
2710 | iteration domain for i and j is not checked. */ | |
2711 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2712 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
2713 | *overlaps_a = conflict_fn_not_known (); | |
2714 | *overlaps_b = conflict_fn_not_known (); | |
2715 | *last_conflicts = chrec_dont_know; | |
56cf8686 SP |
2716 | } |
2717 | } | |
86df10e3 SP |
2718 | else |
2719 | { | |
0ff4040e SP |
2720 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2721 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2722 | *overlaps_a = conflict_fn_not_known (); |
2723 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 SP |
2724 | *last_conflicts = chrec_dont_know; |
2725 | } | |
56cf8686 | 2726 | } |
56cf8686 SP |
2727 | else |
2728 | { | |
0ff4040e SP |
2729 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2730 | fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); | |
d93817c4 ZD |
2731 | *overlaps_a = conflict_fn_not_known (); |
2732 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2733 | *last_conflicts = chrec_dont_know; |
56cf8686 | 2734 | } |
86df10e3 | 2735 | |
b8698a0f | 2736 | end_analyze_subs_aa: |
f873b205 | 2737 | obstack_free (&scratch_obstack, NULL); |
56cf8686 SP |
2738 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2739 | { | |
2740 | fprintf (dump_file, " (overlaps_a = "); | |
d93817c4 | 2741 | dump_conflict_function (dump_file, *overlaps_a); |
56cf8686 | 2742 | fprintf (dump_file, ")\n (overlaps_b = "); |
d93817c4 | 2743 | dump_conflict_function (dump_file, *overlaps_b); |
bcf1ef00 | 2744 | fprintf (dump_file, "))\n"); |
56cf8686 | 2745 | } |
0ff4040e SP |
2746 | } |
2747 | ||
2748 | /* Returns true when analyze_subscript_affine_affine can be used for | |
2749 | determining the dependence relation between chrec_a and chrec_b, | |
2750 | that contain symbols. This function modifies chrec_a and chrec_b | |
2751 | such that the analysis result is the same, and such that they don't | |
b8698a0f | 2752 | contain symbols, and then can safely be passed to the analyzer. |
0ff4040e SP |
2753 | |
2754 | Example: The analysis of the following tuples of evolutions produce | |
2755 | the same results: {x+1, +, 1}_1 vs. {x+3, +, 1}_1, and {-2, +, 1}_1 | |
2756 | vs. {0, +, 1}_1 | |
b8698a0f | 2757 | |
0ff4040e SP |
2758 | {x+1, +, 1}_1 ({2, +, 1}_1) = {x+3, +, 1}_1 ({0, +, 1}_1) |
2759 | {-2, +, 1}_1 ({2, +, 1}_1) = {0, +, 1}_1 ({0, +, 1}_1) | |
2760 | */ | |
2761 | ||
2762 | static bool | |
2763 | can_use_analyze_subscript_affine_affine (tree *chrec_a, tree *chrec_b) | |
2764 | { | |
16a2acea | 2765 | tree diff, type, left_a, left_b, right_b; |
0ff4040e SP |
2766 | |
2767 | if (chrec_contains_symbols (CHREC_RIGHT (*chrec_a)) | |
2768 | || chrec_contains_symbols (CHREC_RIGHT (*chrec_b))) | |
2769 | /* FIXME: For the moment not handled. Might be refined later. */ | |
2770 | return false; | |
2771 | ||
16a2acea SP |
2772 | type = chrec_type (*chrec_a); |
2773 | left_a = CHREC_LEFT (*chrec_a); | |
726a989a | 2774 | left_b = chrec_convert (type, CHREC_LEFT (*chrec_b), NULL); |
16a2acea SP |
2775 | diff = chrec_fold_minus (type, left_a, left_b); |
2776 | ||
0ff4040e SP |
2777 | if (!evolution_function_is_constant_p (diff)) |
2778 | return false; | |
2779 | ||
56cf8686 | 2780 | if (dump_file && (dump_flags & TDF_DETAILS)) |
0ff4040e SP |
2781 | fprintf (dump_file, "can_use_subscript_aff_aff_for_symbolic \n"); |
2782 | ||
b8698a0f | 2783 | *chrec_a = build_polynomial_chrec (CHREC_VARIABLE (*chrec_a), |
0ff4040e | 2784 | diff, CHREC_RIGHT (*chrec_a)); |
726a989a | 2785 | right_b = chrec_convert (type, CHREC_RIGHT (*chrec_b), NULL); |
0ff4040e | 2786 | *chrec_b = build_polynomial_chrec (CHREC_VARIABLE (*chrec_b), |
dc61cc6b | 2787 | build_int_cst (type, 0), |
16a2acea | 2788 | right_b); |
0ff4040e | 2789 | return true; |
56cf8686 SP |
2790 | } |
2791 | ||
2792 | /* Analyze a SIV (Single Index Variable) subscript. *OVERLAPS_A and | |
2793 | *OVERLAPS_B are initialized to the functions that describe the | |
2794 | relation between the elements accessed twice by CHREC_A and | |
2795 | CHREC_B. For k >= 0, the following property is verified: | |
2796 | ||
2797 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2798 | ||
2799 | static void | |
b8698a0f | 2800 | analyze_siv_subscript (tree chrec_a, |
56cf8686 | 2801 | tree chrec_b, |
b8698a0f L |
2802 | conflict_function **overlaps_a, |
2803 | conflict_function **overlaps_b, | |
5b78fc3e JS |
2804 | tree *last_conflicts, |
2805 | int loop_nest_num) | |
56cf8686 | 2806 | { |
0ff4040e | 2807 | dependence_stats.num_siv++; |
b8698a0f | 2808 | |
56cf8686 SP |
2809 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2810 | fprintf (dump_file, "(analyze_siv_subscript \n"); | |
b8698a0f | 2811 | |
56cf8686 | 2812 | if (evolution_function_is_constant_p (chrec_a) |
5b78fc3e | 2813 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) |
b8698a0f | 2814 | analyze_siv_subscript_cst_affine (chrec_a, chrec_b, |
86df10e3 | 2815 | overlaps_a, overlaps_b, last_conflicts); |
b8698a0f | 2816 | |
5b78fc3e | 2817 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
56cf8686 | 2818 | && evolution_function_is_constant_p (chrec_b)) |
b8698a0f | 2819 | analyze_siv_subscript_cst_affine (chrec_b, chrec_a, |
86df10e3 | 2820 | overlaps_b, overlaps_a, last_conflicts); |
b8698a0f | 2821 | |
5b78fc3e JS |
2822 | else if (evolution_function_is_affine_in_loop (chrec_a, loop_nest_num) |
2823 | && evolution_function_is_affine_in_loop (chrec_b, loop_nest_num)) | |
0ff4040e SP |
2824 | { |
2825 | if (!chrec_contains_symbols (chrec_a) | |
2826 | && !chrec_contains_symbols (chrec_b)) | |
2827 | { | |
b8698a0f L |
2828 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2829 | overlaps_a, overlaps_b, | |
0ff4040e SP |
2830 | last_conflicts); |
2831 | ||
d93817c4 ZD |
2832 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2833 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2834 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2835 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2836 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2837 | dependence_stats.num_siv_independent++; |
2838 | else | |
2839 | dependence_stats.num_siv_dependent++; | |
2840 | } | |
b8698a0f | 2841 | else if (can_use_analyze_subscript_affine_affine (&chrec_a, |
0ff4040e SP |
2842 | &chrec_b)) |
2843 | { | |
b8698a0f L |
2844 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
2845 | overlaps_a, overlaps_b, | |
0ff4040e | 2846 | last_conflicts); |
0ff4040e | 2847 | |
d93817c4 ZD |
2848 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2849 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2850 | dependence_stats.num_siv_unimplemented++; |
d93817c4 ZD |
2851 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2852 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2853 | dependence_stats.num_siv_independent++; |
2854 | else | |
2855 | dependence_stats.num_siv_dependent++; | |
2856 | } | |
2857 | else | |
2858 | goto siv_subscript_dontknow; | |
2859 | } | |
2860 | ||
56cf8686 SP |
2861 | else |
2862 | { | |
0ff4040e SP |
2863 | siv_subscript_dontknow:; |
2864 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
bcf1ef00 | 2865 | fprintf (dump_file, " siv test failed: unimplemented"); |
d93817c4 ZD |
2866 | *overlaps_a = conflict_fn_not_known (); |
2867 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2868 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2869 | dependence_stats.num_siv_unimplemented++; |
56cf8686 | 2870 | } |
b8698a0f | 2871 | |
56cf8686 SP |
2872 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2873 | fprintf (dump_file, ")\n"); | |
2874 | } | |
2875 | ||
55a700ac ZD |
2876 | /* Returns false if we can prove that the greatest common divisor of the steps |
2877 | of CHREC does not divide CST, false otherwise. */ | |
56cf8686 SP |
2878 | |
2879 | static bool | |
ed7a4b4b | 2880 | gcd_of_steps_may_divide_p (const_tree chrec, const_tree cst) |
56cf8686 | 2881 | { |
55a700ac ZD |
2882 | HOST_WIDE_INT cd = 0, val; |
2883 | tree step; | |
0ff4040e | 2884 | |
9541ffee | 2885 | if (!tree_fits_shwi_p (cst)) |
55a700ac | 2886 | return true; |
9439e9a1 | 2887 | val = tree_to_shwi (cst); |
55a700ac ZD |
2888 | |
2889 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC) | |
2890 | { | |
2891 | step = CHREC_RIGHT (chrec); | |
9541ffee | 2892 | if (!tree_fits_shwi_p (step)) |
55a700ac | 2893 | return true; |
9439e9a1 | 2894 | cd = gcd (cd, tree_to_shwi (step)); |
55a700ac | 2895 | chrec = CHREC_LEFT (chrec); |
56cf8686 | 2896 | } |
55a700ac ZD |
2897 | |
2898 | return val % cd == 0; | |
56cf8686 SP |
2899 | } |
2900 | ||
da9a21f4 SP |
2901 | /* Analyze a MIV (Multiple Index Variable) subscript with respect to |
2902 | LOOP_NEST. *OVERLAPS_A and *OVERLAPS_B are initialized to the | |
2903 | functions that describe the relation between the elements accessed | |
2904 | twice by CHREC_A and CHREC_B. For k >= 0, the following property | |
2905 | is verified: | |
56cf8686 SP |
2906 | |
2907 | CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ | |
2908 | ||
2909 | static void | |
b8698a0f L |
2910 | analyze_miv_subscript (tree chrec_a, |
2911 | tree chrec_b, | |
2912 | conflict_function **overlaps_a, | |
2913 | conflict_function **overlaps_b, | |
da9a21f4 SP |
2914 | tree *last_conflicts, |
2915 | struct loop *loop_nest) | |
56cf8686 | 2916 | { |
33b30201 SP |
2917 | tree type, difference; |
2918 | ||
0ff4040e | 2919 | dependence_stats.num_miv++; |
56cf8686 SP |
2920 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2921 | fprintf (dump_file, "(analyze_miv_subscript \n"); | |
e2157b49 | 2922 | |
33b30201 | 2923 | type = signed_type_for_types (TREE_TYPE (chrec_a), TREE_TYPE (chrec_b)); |
726a989a RB |
2924 | chrec_a = chrec_convert (type, chrec_a, NULL); |
2925 | chrec_b = chrec_convert (type, chrec_b, NULL); | |
33b30201 | 2926 | difference = chrec_fold_minus (type, chrec_a, chrec_b); |
b8698a0f | 2927 | |
e2157b49 | 2928 | if (eq_evolutions_p (chrec_a, chrec_b)) |
56cf8686 SP |
2929 | { |
2930 | /* Access functions are the same: all the elements are accessed | |
2931 | in the same order. */ | |
d93817c4 ZD |
2932 | *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
2933 | *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
b4a9343c | 2934 | *last_conflicts = max_stmt_executions_tree (get_chrec_loop (chrec_a)); |
0ff4040e | 2935 | dependence_stats.num_miv_dependent++; |
56cf8686 | 2936 | } |
b8698a0f | 2937 | |
56cf8686 SP |
2938 | else if (evolution_function_is_constant_p (difference) |
2939 | /* For the moment, the following is verified: | |
da9a21f4 SP |
2940 | evolution_function_is_affine_multivariate_p (chrec_a, |
2941 | loop_nest->num) */ | |
55a700ac | 2942 | && !gcd_of_steps_may_divide_p (chrec_a, difference)) |
56cf8686 SP |
2943 | { |
2944 | /* testsuite/.../ssa-chrec-33.c | |
b8698a0f L |
2945 | {{21, +, 2}_1, +, -2}_2 vs. {{20, +, 2}_1, +, -2}_2 |
2946 | ||
55a700ac ZD |
2947 | The difference is 1, and all the evolution steps are multiples |
2948 | of 2, consequently there are no overlapping elements. */ | |
d93817c4 ZD |
2949 | *overlaps_a = conflict_fn_no_dependence (); |
2950 | *overlaps_b = conflict_fn_no_dependence (); | |
86df10e3 | 2951 | *last_conflicts = integer_zero_node; |
0ff4040e | 2952 | dependence_stats.num_miv_independent++; |
56cf8686 | 2953 | } |
b8698a0f | 2954 | |
da9a21f4 | 2955 | else if (evolution_function_is_affine_multivariate_p (chrec_a, loop_nest->num) |
0ff4040e | 2956 | && !chrec_contains_symbols (chrec_a) |
da9a21f4 | 2957 | && evolution_function_is_affine_multivariate_p (chrec_b, loop_nest->num) |
0ff4040e | 2958 | && !chrec_contains_symbols (chrec_b)) |
56cf8686 SP |
2959 | { |
2960 | /* testsuite/.../ssa-chrec-35.c | |
2961 | {0, +, 1}_2 vs. {0, +, 1}_3 | |
2962 | the overlapping elements are respectively located at iterations: | |
b8698a0f L |
2963 | {0, +, 1}_x and {0, +, 1}_x, |
2964 | in other words, we have the equality: | |
86df10e3 | 2965 | {0, +, 1}_2 ({0, +, 1}_x) = {0, +, 1}_3 ({0, +, 1}_x) |
b8698a0f L |
2966 | |
2967 | Other examples: | |
2968 | {{0, +, 1}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) = | |
86df10e3 SP |
2969 | {0, +, 1}_1 ({{0, +, 1}_x, +, 2}_y) |
2970 | ||
b8698a0f | 2971 | {{0, +, 2}_1, +, 3}_2 ({0, +, 1}_y, {0, +, 1}_x) = |
86df10e3 | 2972 | {{0, +, 3}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) |
56cf8686 | 2973 | */ |
b8698a0f | 2974 | analyze_subscript_affine_affine (chrec_a, chrec_b, |
86df10e3 | 2975 | overlaps_a, overlaps_b, last_conflicts); |
0ff4040e | 2976 | |
d93817c4 ZD |
2977 | if (CF_NOT_KNOWN_P (*overlaps_a) |
2978 | || CF_NOT_KNOWN_P (*overlaps_b)) | |
0ff4040e | 2979 | dependence_stats.num_miv_unimplemented++; |
d93817c4 ZD |
2980 | else if (CF_NO_DEPENDENCE_P (*overlaps_a) |
2981 | || CF_NO_DEPENDENCE_P (*overlaps_b)) | |
0ff4040e SP |
2982 | dependence_stats.num_miv_independent++; |
2983 | else | |
2984 | dependence_stats.num_miv_dependent++; | |
56cf8686 | 2985 | } |
b8698a0f | 2986 | |
56cf8686 SP |
2987 | else |
2988 | { | |
2989 | /* When the analysis is too difficult, answer "don't know". */ | |
0ff4040e SP |
2990 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2991 | fprintf (dump_file, "analyze_miv_subscript test failed: unimplemented.\n"); | |
2992 | ||
d93817c4 ZD |
2993 | *overlaps_a = conflict_fn_not_known (); |
2994 | *overlaps_b = conflict_fn_not_known (); | |
86df10e3 | 2995 | *last_conflicts = chrec_dont_know; |
0ff4040e | 2996 | dependence_stats.num_miv_unimplemented++; |
56cf8686 | 2997 | } |
b8698a0f | 2998 | |
56cf8686 SP |
2999 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3000 | fprintf (dump_file, ")\n"); | |
3001 | } | |
3002 | ||
da9a21f4 SP |
3003 | /* Determines the iterations for which CHREC_A is equal to CHREC_B in |
3004 | with respect to LOOP_NEST. OVERLAP_ITERATIONS_A and | |
3005 | OVERLAP_ITERATIONS_B are initialized with two functions that | |
3006 | describe the iterations that contain conflicting elements. | |
b8698a0f | 3007 | |
56cf8686 | 3008 | Remark: For an integer k >= 0, the following equality is true: |
b8698a0f | 3009 | |
56cf8686 SP |
3010 | CHREC_A (OVERLAP_ITERATIONS_A (k)) == CHREC_B (OVERLAP_ITERATIONS_B (k)). |
3011 | */ | |
3012 | ||
b8698a0f L |
3013 | static void |
3014 | analyze_overlapping_iterations (tree chrec_a, | |
3015 | tree chrec_b, | |
3016 | conflict_function **overlap_iterations_a, | |
3017 | conflict_function **overlap_iterations_b, | |
da9a21f4 | 3018 | tree *last_conflicts, struct loop *loop_nest) |
56cf8686 | 3019 | { |
da9a21f4 SP |
3020 | unsigned int lnn = loop_nest->num; |
3021 | ||
0ff4040e | 3022 | dependence_stats.num_subscript_tests++; |
b8698a0f | 3023 | |
56cf8686 SP |
3024 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3025 | { | |
3026 | fprintf (dump_file, "(analyze_overlapping_iterations \n"); | |
3027 | fprintf (dump_file, " (chrec_a = "); | |
3028 | print_generic_expr (dump_file, chrec_a, 0); | |
0ff4040e | 3029 | fprintf (dump_file, ")\n (chrec_b = "); |
56cf8686 SP |
3030 | print_generic_expr (dump_file, chrec_b, 0); |
3031 | fprintf (dump_file, ")\n"); | |
3032 | } | |
0ff4040e | 3033 | |
56cf8686 SP |
3034 | if (chrec_a == NULL_TREE |
3035 | || chrec_b == NULL_TREE | |
3036 | || chrec_contains_undetermined (chrec_a) | |
0ff4040e | 3037 | || chrec_contains_undetermined (chrec_b)) |
56cf8686 | 3038 | { |
0ff4040e | 3039 | dependence_stats.num_subscript_undetermined++; |
b8698a0f | 3040 | |
d93817c4 ZD |
3041 | *overlap_iterations_a = conflict_fn_not_known (); |
3042 | *overlap_iterations_b = conflict_fn_not_known (); | |
56cf8686 | 3043 | } |
0ff4040e | 3044 | |
b8698a0f | 3045 | /* If they are the same chrec, and are affine, they overlap |
0ff4040e SP |
3046 | on every iteration. */ |
3047 | else if (eq_evolutions_p (chrec_a, chrec_b) | |
3e6f8b56 SP |
3048 | && (evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
3049 | || operand_equal_p (chrec_a, chrec_b, 0))) | |
0ff4040e SP |
3050 | { |
3051 | dependence_stats.num_same_subscript_function++; | |
d93817c4 ZD |
3052 | *overlap_iterations_a = conflict_fn (1, affine_fn_cst (integer_zero_node)); |
3053 | *overlap_iterations_b = conflict_fn (1, affine_fn_cst (integer_zero_node)); | |
0ff4040e SP |
3054 | *last_conflicts = chrec_dont_know; |
3055 | } | |
3056 | ||
3057 | /* If they aren't the same, and aren't affine, we can't do anything | |
3e6f8b56 | 3058 | yet. */ |
b8698a0f | 3059 | else if ((chrec_contains_symbols (chrec_a) |
0ff4040e | 3060 | || chrec_contains_symbols (chrec_b)) |
da9a21f4 SP |
3061 | && (!evolution_function_is_affine_multivariate_p (chrec_a, lnn) |
3062 | || !evolution_function_is_affine_multivariate_p (chrec_b, lnn))) | |
0ff4040e SP |
3063 | { |
3064 | dependence_stats.num_subscript_undetermined++; | |
d93817c4 ZD |
3065 | *overlap_iterations_a = conflict_fn_not_known (); |
3066 | *overlap_iterations_b = conflict_fn_not_known (); | |
0ff4040e SP |
3067 | } |
3068 | ||
56cf8686 | 3069 | else if (ziv_subscript_p (chrec_a, chrec_b)) |
b8698a0f | 3070 | analyze_ziv_subscript (chrec_a, chrec_b, |
86df10e3 SP |
3071 | overlap_iterations_a, overlap_iterations_b, |
3072 | last_conflicts); | |
b8698a0f | 3073 | |
56cf8686 | 3074 | else if (siv_subscript_p (chrec_a, chrec_b)) |
b8698a0f L |
3075 | analyze_siv_subscript (chrec_a, chrec_b, |
3076 | overlap_iterations_a, overlap_iterations_b, | |
5b78fc3e | 3077 | last_conflicts, lnn); |
b8698a0f | 3078 | |
56cf8686 | 3079 | else |
b8698a0f | 3080 | analyze_miv_subscript (chrec_a, chrec_b, |
86df10e3 | 3081 | overlap_iterations_a, overlap_iterations_b, |
da9a21f4 | 3082 | last_conflicts, loop_nest); |
b8698a0f | 3083 | |
56cf8686 SP |
3084 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3085 | { | |
3086 | fprintf (dump_file, " (overlap_iterations_a = "); | |
d93817c4 | 3087 | dump_conflict_function (dump_file, *overlap_iterations_a); |
56cf8686 | 3088 | fprintf (dump_file, ")\n (overlap_iterations_b = "); |
d93817c4 | 3089 | dump_conflict_function (dump_file, *overlap_iterations_b); |
bcf1ef00 | 3090 | fprintf (dump_file, "))\n"); |
56cf8686 SP |
3091 | } |
3092 | } | |
3093 | ||
ba42e045 | 3094 | /* Helper function for uniquely inserting distance vectors. */ |
56cf8686 | 3095 | |
ba42e045 SP |
3096 | static void |
3097 | save_dist_v (struct data_dependence_relation *ddr, lambda_vector dist_v) | |
3098 | { | |
3099 | unsigned i; | |
3100 | lambda_vector v; | |
56cf8686 | 3101 | |
9771b263 | 3102 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, v) |
ba42e045 SP |
3103 | if (lambda_vector_equal (v, dist_v, DDR_NB_LOOPS (ddr))) |
3104 | return; | |
56cf8686 | 3105 | |
9771b263 | 3106 | DDR_DIST_VECTS (ddr).safe_push (dist_v); |
ba42e045 | 3107 | } |
56cf8686 | 3108 | |
ba42e045 SP |
3109 | /* Helper function for uniquely inserting direction vectors. */ |
3110 | ||
3111 | static void | |
3112 | save_dir_v (struct data_dependence_relation *ddr, lambda_vector dir_v) | |
56cf8686 SP |
3113 | { |
3114 | unsigned i; | |
ba42e045 | 3115 | lambda_vector v; |
0ff4040e | 3116 | |
9771b263 | 3117 | FOR_EACH_VEC_ELT (DDR_DIR_VECTS (ddr), i, v) |
ba42e045 SP |
3118 | if (lambda_vector_equal (v, dir_v, DDR_NB_LOOPS (ddr))) |
3119 | return; | |
3120 | ||
9771b263 | 3121 | DDR_DIR_VECTS (ddr).safe_push (dir_v); |
ba42e045 SP |
3122 | } |
3123 | ||
3124 | /* Add a distance of 1 on all the loops outer than INDEX. If we | |
3125 | haven't yet determined a distance for this outer loop, push a new | |
3126 | distance vector composed of the previous distance, and a distance | |
3127 | of 1 for this outer loop. Example: | |
3128 | ||
3129 | | loop_1 | |
3130 | | loop_2 | |
3131 | | A[10] | |
3132 | | endloop_2 | |
3133 | | endloop_1 | |
3134 | ||
3135 | Saved vectors are of the form (dist_in_1, dist_in_2). First, we | |
3136 | save (0, 1), then we have to save (1, 0). */ | |
3137 | ||
3138 | static void | |
3139 | add_outer_distances (struct data_dependence_relation *ddr, | |
3140 | lambda_vector dist_v, int index) | |
3141 | { | |
3142 | /* For each outer loop where init_v is not set, the accesses are | |
3143 | in dependence of distance 1 in the loop. */ | |
3144 | while (--index >= 0) | |
3145 | { | |
3146 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3147 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
3148 | save_v[index] = 1; | |
3149 | save_dist_v (ddr, save_v); | |
3150 | } | |
3151 | } | |
3152 | ||
3153 | /* Return false when fail to represent the data dependence as a | |
3154 | distance vector. INIT_B is set to true when a component has been | |
3155 | added to the distance vector DIST_V. INDEX_CARRY is then set to | |
3156 | the index in DIST_V that carries the dependence. */ | |
3157 | ||
3158 | static bool | |
3159 | build_classic_dist_vector_1 (struct data_dependence_relation *ddr, | |
3160 | struct data_reference *ddr_a, | |
3161 | struct data_reference *ddr_b, | |
3162 | lambda_vector dist_v, bool *init_b, | |
3163 | int *index_carry) | |
3164 | { | |
3165 | unsigned i; | |
3166 | lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
0ff4040e | 3167 | |
36d59cf7 | 3168 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
56cf8686 | 3169 | { |
86df10e3 | 3170 | tree access_fn_a, access_fn_b; |
36d59cf7 | 3171 | struct subscript *subscript = DDR_SUBSCRIPT (ddr, i); |
56cf8686 SP |
3172 | |
3173 | if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
3174 | { |
3175 | non_affine_dependence_relation (ddr); | |
ba42e045 | 3176 | return false; |
86df10e3 SP |
3177 | } |
3178 | ||
ba42e045 SP |
3179 | access_fn_a = DR_ACCESS_FN (ddr_a, i); |
3180 | access_fn_b = DR_ACCESS_FN (ddr_b, i); | |
56cf8686 | 3181 | |
b8698a0f | 3182 | if (TREE_CODE (access_fn_a) == POLYNOMIAL_CHREC |
86df10e3 | 3183 | && TREE_CODE (access_fn_b) == POLYNOMIAL_CHREC) |
56cf8686 | 3184 | { |
ba42e045 | 3185 | int dist, index; |
a130584a SP |
3186 | int var_a = CHREC_VARIABLE (access_fn_a); |
3187 | int var_b = CHREC_VARIABLE (access_fn_b); | |
ba42e045 | 3188 | |
a130584a SP |
3189 | if (var_a != var_b |
3190 | || chrec_contains_undetermined (SUB_DISTANCE (subscript))) | |
86df10e3 SP |
3191 | { |
3192 | non_affine_dependence_relation (ddr); | |
ba42e045 | 3193 | return false; |
86df10e3 | 3194 | } |
b8698a0f | 3195 | |
6b6fa4e9 | 3196 | dist = int_cst_value (SUB_DISTANCE (subscript)); |
a130584a SP |
3197 | index = index_in_loop_nest (var_a, DDR_LOOP_NEST (ddr)); |
3198 | *index_carry = MIN (index, *index_carry); | |
56cf8686 | 3199 | |
ba42e045 SP |
3200 | /* This is the subscript coupling test. If we have already |
3201 | recorded a distance for this loop (a distance coming from | |
3202 | another subscript), it should be the same. For example, | |
3203 | in the following code, there is no dependence: | |
3204 | ||
56cf8686 SP |
3205 | | loop i = 0, N, 1 |
3206 | | T[i+1][i] = ... | |
3207 | | ... = T[i][i] | |
3208 | | endloop | |
ba42e045 SP |
3209 | */ |
3210 | if (init_v[index] != 0 && dist_v[index] != dist) | |
56cf8686 | 3211 | { |
36d59cf7 | 3212 | finalize_ddr_dependent (ddr, chrec_known); |
ba42e045 | 3213 | return false; |
56cf8686 SP |
3214 | } |
3215 | ||
ba42e045 SP |
3216 | dist_v[index] = dist; |
3217 | init_v[index] = 1; | |
3218 | *init_b = true; | |
3219 | } | |
a50411de | 3220 | else if (!operand_equal_p (access_fn_a, access_fn_b, 0)) |
ba42e045 SP |
3221 | { |
3222 | /* This can be for example an affine vs. constant dependence | |
3223 | (T[i] vs. T[3]) that is not an affine dependence and is | |
3224 | not representable as a distance vector. */ | |
3225 | non_affine_dependence_relation (ddr); | |
3226 | return false; | |
56cf8686 SP |
3227 | } |
3228 | } | |
304afda6 | 3229 | |
ba42e045 SP |
3230 | return true; |
3231 | } | |
304afda6 | 3232 | |
1baf2906 SP |
3233 | /* Return true when the DDR contains only constant access functions. */ |
3234 | ||
3235 | static bool | |
ed7a4b4b | 3236 | constant_access_functions (const struct data_dependence_relation *ddr) |
1baf2906 SP |
3237 | { |
3238 | unsigned i; | |
3239 | ||
3240 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3241 | if (!evolution_function_is_constant_p (DR_ACCESS_FN (DDR_A (ddr), i)) | |
3242 | || !evolution_function_is_constant_p (DR_ACCESS_FN (DDR_B (ddr), i))) | |
3243 | return false; | |
3244 | ||
3245 | return true; | |
3246 | } | |
3247 | ||
ba42e045 | 3248 | /* Helper function for the case where DDR_A and DDR_B are the same |
097392de SP |
3249 | multivariate access function with a constant step. For an example |
3250 | see pr34635-1.c. */ | |
86df10e3 | 3251 | |
ba42e045 SP |
3252 | static void |
3253 | add_multivariate_self_dist (struct data_dependence_relation *ddr, tree c_2) | |
3254 | { | |
3255 | int x_1, x_2; | |
3256 | tree c_1 = CHREC_LEFT (c_2); | |
3257 | tree c_0 = CHREC_LEFT (c_1); | |
3258 | lambda_vector dist_v; | |
0ca2faee | 3259 | int v1, v2, cd; |
86df10e3 | 3260 | |
b1e75954 SP |
3261 | /* Polynomials with more than 2 variables are not handled yet. When |
3262 | the evolution steps are parameters, it is not possible to | |
3263 | represent the dependence using classical distance vectors. */ | |
3264 | if (TREE_CODE (c_0) != INTEGER_CST | |
3265 | || TREE_CODE (CHREC_RIGHT (c_1)) != INTEGER_CST | |
3266 | || TREE_CODE (CHREC_RIGHT (c_2)) != INTEGER_CST) | |
3267 | { | |
3268 | DDR_AFFINE_P (ddr) = false; | |
ba42e045 SP |
3269 | return; |
3270 | } | |
304afda6 | 3271 | |
ba42e045 SP |
3272 | x_2 = index_in_loop_nest (CHREC_VARIABLE (c_2), DDR_LOOP_NEST (ddr)); |
3273 | x_1 = index_in_loop_nest (CHREC_VARIABLE (c_1), DDR_LOOP_NEST (ddr)); | |
304afda6 | 3274 | |
ba42e045 SP |
3275 | /* For "{{0, +, 2}_1, +, 3}_2" the distance vector is (3, -2). */ |
3276 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
6b6fa4e9 SP |
3277 | v1 = int_cst_value (CHREC_RIGHT (c_1)); |
3278 | v2 = int_cst_value (CHREC_RIGHT (c_2)); | |
0ca2faee ZD |
3279 | cd = gcd (v1, v2); |
3280 | v1 /= cd; | |
3281 | v2 /= cd; | |
3282 | ||
3283 | if (v2 < 0) | |
3284 | { | |
3285 | v2 = -v2; | |
3286 | v1 = -v1; | |
3287 | } | |
3288 | ||
3289 | dist_v[x_1] = v2; | |
3290 | dist_v[x_2] = -v1; | |
ba42e045 | 3291 | save_dist_v (ddr, dist_v); |
304afda6 | 3292 | |
ba42e045 SP |
3293 | add_outer_distances (ddr, dist_v, x_1); |
3294 | } | |
304afda6 | 3295 | |
ba42e045 SP |
3296 | /* Helper function for the case where DDR_A and DDR_B are the same |
3297 | access functions. */ | |
37b8a73b | 3298 | |
ba42e045 SP |
3299 | static void |
3300 | add_other_self_distances (struct data_dependence_relation *ddr) | |
3301 | { | |
3302 | lambda_vector dist_v; | |
3303 | unsigned i; | |
3304 | int index_carry = DDR_NB_LOOPS (ddr); | |
304afda6 | 3305 | |
ba42e045 | 3306 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) |
37b8a73b | 3307 | { |
ba42e045 | 3308 | tree access_fun = DR_ACCESS_FN (DDR_A (ddr), i); |
304afda6 | 3309 | |
ba42e045 | 3310 | if (TREE_CODE (access_fun) == POLYNOMIAL_CHREC) |
304afda6 | 3311 | { |
ba42e045 SP |
3312 | if (!evolution_function_is_univariate_p (access_fun)) |
3313 | { | |
3314 | if (DDR_NUM_SUBSCRIPTS (ddr) != 1) | |
3315 | { | |
3316 | DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; | |
3317 | return; | |
3318 | } | |
3319 | ||
097392de SP |
3320 | access_fun = DR_ACCESS_FN (DDR_A (ddr), 0); |
3321 | ||
3322 | if (TREE_CODE (CHREC_LEFT (access_fun)) == POLYNOMIAL_CHREC) | |
3323 | add_multivariate_self_dist (ddr, access_fun); | |
3324 | else | |
3325 | /* The evolution step is not constant: it varies in | |
3326 | the outer loop, so this cannot be represented by a | |
3327 | distance vector. For example in pr34635.c the | |
3328 | evolution is {0, +, {0, +, 4}_1}_2. */ | |
3329 | DDR_AFFINE_P (ddr) = false; | |
3330 | ||
ba42e045 SP |
3331 | return; |
3332 | } | |
3333 | ||
3334 | index_carry = MIN (index_carry, | |
3335 | index_in_loop_nest (CHREC_VARIABLE (access_fun), | |
3336 | DDR_LOOP_NEST (ddr))); | |
304afda6 | 3337 | } |
37b8a73b SP |
3338 | } |
3339 | ||
ba42e045 SP |
3340 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3341 | add_outer_distances (ddr, dist_v, index_carry); | |
56cf8686 SP |
3342 | } |
3343 | ||
1baf2906 SP |
3344 | static void |
3345 | insert_innermost_unit_dist_vector (struct data_dependence_relation *ddr) | |
3346 | { | |
3347 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3348 | ||
3349 | dist_v[DDR_INNER_LOOP (ddr)] = 1; | |
3350 | save_dist_v (ddr, dist_v); | |
3351 | } | |
3352 | ||
3353 | /* Adds a unit distance vector to DDR when there is a 0 overlap. This | |
3354 | is the case for example when access functions are the same and | |
3355 | equal to a constant, as in: | |
3356 | ||
3357 | | loop_1 | |
3358 | | A[3] = ... | |
3359 | | ... = A[3] | |
3360 | | endloop_1 | |
3361 | ||
3362 | in which case the distance vectors are (0) and (1). */ | |
3363 | ||
3364 | static void | |
3365 | add_distance_for_zero_overlaps (struct data_dependence_relation *ddr) | |
3366 | { | |
3367 | unsigned i, j; | |
3368 | ||
3369 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3370 | { | |
3371 | subscript_p sub = DDR_SUBSCRIPT (ddr, i); | |
3372 | conflict_function *ca = SUB_CONFLICTS_IN_A (sub); | |
3373 | conflict_function *cb = SUB_CONFLICTS_IN_B (sub); | |
3374 | ||
3375 | for (j = 0; j < ca->n; j++) | |
3376 | if (affine_function_zero_p (ca->fns[j])) | |
3377 | { | |
3378 | insert_innermost_unit_dist_vector (ddr); | |
3379 | return; | |
3380 | } | |
3381 | ||
3382 | for (j = 0; j < cb->n; j++) | |
3383 | if (affine_function_zero_p (cb->fns[j])) | |
3384 | { | |
3385 | insert_innermost_unit_dist_vector (ddr); | |
3386 | return; | |
3387 | } | |
3388 | } | |
3389 | } | |
3390 | ||
ba42e045 SP |
3391 | /* Compute the classic per loop distance vector. DDR is the data |
3392 | dependence relation to build a vector from. Return false when fail | |
3393 | to represent the data dependence as a distance vector. */ | |
56cf8686 | 3394 | |
464f49d8 | 3395 | static bool |
da9a21f4 SP |
3396 | build_classic_dist_vector (struct data_dependence_relation *ddr, |
3397 | struct loop *loop_nest) | |
56cf8686 | 3398 | { |
304afda6 | 3399 | bool init_b = false; |
ba42e045 SP |
3400 | int index_carry = DDR_NB_LOOPS (ddr); |
3401 | lambda_vector dist_v; | |
304afda6 | 3402 | |
36d59cf7 | 3403 | if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) |
2f470326 | 3404 | return false; |
ba42e045 SP |
3405 | |
3406 | if (same_access_functions (ddr)) | |
56cf8686 | 3407 | { |
ba42e045 SP |
3408 | /* Save the 0 vector. */ |
3409 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3410 | save_dist_v (ddr, dist_v); | |
56cf8686 | 3411 | |
1baf2906 SP |
3412 | if (constant_access_functions (ddr)) |
3413 | add_distance_for_zero_overlaps (ddr); | |
3414 | ||
ba42e045 SP |
3415 | if (DDR_NB_LOOPS (ddr) > 1) |
3416 | add_other_self_distances (ddr); | |
86df10e3 | 3417 | |
ba42e045 SP |
3418 | return true; |
3419 | } | |
86df10e3 | 3420 | |
ba42e045 SP |
3421 | dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
3422 | if (!build_classic_dist_vector_1 (ddr, DDR_A (ddr), DDR_B (ddr), | |
3423 | dist_v, &init_b, &index_carry)) | |
3424 | return false; | |
86df10e3 | 3425 | |
ba42e045 SP |
3426 | /* Save the distance vector if we initialized one. */ |
3427 | if (init_b) | |
3428 | { | |
3429 | /* Verify a basic constraint: classic distance vectors should | |
3430 | always be lexicographically positive. | |
3431 | ||
3432 | Data references are collected in the order of execution of | |
3433 | the program, thus for the following loop | |
3434 | ||
3435 | | for (i = 1; i < 100; i++) | |
3436 | | for (j = 1; j < 100; j++) | |
3437 | | { | |
3438 | | t = T[j+1][i-1]; // A | |
3439 | | T[j][i] = t + 2; // B | |
3440 | | } | |
3441 | ||
3442 | references are collected following the direction of the wind: | |
3443 | A then B. The data dependence tests are performed also | |
3444 | following this order, such that we're looking at the distance | |
3445 | separating the elements accessed by A from the elements later | |
3446 | accessed by B. But in this example, the distance returned by | |
3447 | test_dep (A, B) is lexicographically negative (-1, 1), that | |
3448 | means that the access A occurs later than B with respect to | |
3449 | the outer loop, ie. we're actually looking upwind. In this | |
3450 | case we solve test_dep (B, A) looking downwind to the | |
3451 | lexicographically positive solution, that returns the | |
3452 | distance vector (1, -1). */ | |
3453 | if (!lambda_vector_lexico_pos (dist_v, DDR_NB_LOOPS (ddr))) | |
3454 | { | |
3455 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
2f470326 JJ |
3456 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3457 | loop_nest)) | |
3458 | return false; | |
ba42e045 | 3459 | compute_subscript_distance (ddr); |
2f470326 JJ |
3460 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3461 | save_v, &init_b, &index_carry)) | |
3462 | return false; | |
ba42e045 | 3463 | save_dist_v (ddr, save_v); |
71d5b5e1 | 3464 | DDR_REVERSED_P (ddr) = true; |
ba42e045 SP |
3465 | |
3466 | /* In this case there is a dependence forward for all the | |
3467 | outer loops: | |
3468 | ||
3469 | | for (k = 1; k < 100; k++) | |
3470 | | for (i = 1; i < 100; i++) | |
3471 | | for (j = 1; j < 100; j++) | |
3472 | | { | |
3473 | | t = T[j+1][i-1]; // A | |
3474 | | T[j][i] = t + 2; // B | |
3475 | | } | |
3476 | ||
b8698a0f | 3477 | the vectors are: |
ba42e045 SP |
3478 | (0, 1, -1) |
3479 | (1, 1, -1) | |
3480 | (1, -1, 1) | |
3481 | */ | |
3482 | if (DDR_NB_LOOPS (ddr) > 1) | |
3483 | { | |
3484 | add_outer_distances (ddr, save_v, index_carry); | |
3485 | add_outer_distances (ddr, dist_v, index_carry); | |
86df10e3 | 3486 | } |
ba42e045 SP |
3487 | } |
3488 | else | |
3489 | { | |
3490 | lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3491 | lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3492 | |
ba42e045 | 3493 | if (DDR_NB_LOOPS (ddr) > 1) |
56cf8686 | 3494 | { |
ba42e045 | 3495 | lambda_vector opposite_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); |
86df10e3 | 3496 | |
2f470326 JJ |
3497 | if (!subscript_dependence_tester_1 (ddr, DDR_B (ddr), |
3498 | DDR_A (ddr), loop_nest)) | |
3499 | return false; | |
ba42e045 | 3500 | compute_subscript_distance (ddr); |
2f470326 JJ |
3501 | if (!build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), |
3502 | opposite_v, &init_b, | |
3503 | &index_carry)) | |
3504 | return false; | |
86df10e3 | 3505 | |
2f470326 | 3506 | save_dist_v (ddr, save_v); |
ba42e045 SP |
3507 | add_outer_distances (ddr, dist_v, index_carry); |
3508 | add_outer_distances (ddr, opposite_v, index_carry); | |
56cf8686 | 3509 | } |
2f470326 JJ |
3510 | else |
3511 | save_dist_v (ddr, save_v); | |
56cf8686 SP |
3512 | } |
3513 | } | |
ba42e045 SP |
3514 | else |
3515 | { | |
3516 | /* There is a distance of 1 on all the outer loops: Example: | |
3517 | there is a dependence of distance 1 on loop_1 for the array A. | |
304afda6 | 3518 | |
ba42e045 SP |
3519 | | loop_1 |
3520 | | A[5] = ... | |
3521 | | endloop | |
3522 | */ | |
3523 | add_outer_distances (ddr, dist_v, | |
3524 | lambda_vector_first_nz (dist_v, | |
3525 | DDR_NB_LOOPS (ddr), 0)); | |
3526 | } | |
3527 | ||
3528 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
304afda6 | 3529 | { |
ba42e045 | 3530 | unsigned i; |
304afda6 | 3531 | |
ba42e045 SP |
3532 | fprintf (dump_file, "(build_classic_dist_vector\n"); |
3533 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
3534 | { | |
3535 | fprintf (dump_file, " dist_vector = ("); | |
3536 | print_lambda_vector (dump_file, DDR_DIST_VECT (ddr, i), | |
3537 | DDR_NB_LOOPS (ddr)); | |
3538 | fprintf (dump_file, " )\n"); | |
3539 | } | |
3540 | fprintf (dump_file, ")\n"); | |
304afda6 SP |
3541 | } |
3542 | ||
ba42e045 SP |
3543 | return true; |
3544 | } | |
56cf8686 | 3545 | |
ba42e045 SP |
3546 | /* Return the direction for a given distance. |
3547 | FIXME: Computing dir this way is suboptimal, since dir can catch | |
3548 | cases that dist is unable to represent. */ | |
86df10e3 | 3549 | |
ba42e045 SP |
3550 | static inline enum data_dependence_direction |
3551 | dir_from_dist (int dist) | |
3552 | { | |
3553 | if (dist > 0) | |
3554 | return dir_positive; | |
3555 | else if (dist < 0) | |
3556 | return dir_negative; | |
3557 | else | |
3558 | return dir_equal; | |
3559 | } | |
304afda6 | 3560 | |
ba42e045 SP |
3561 | /* Compute the classic per loop direction vector. DDR is the data |
3562 | dependence relation to build a vector from. */ | |
304afda6 | 3563 | |
ba42e045 SP |
3564 | static void |
3565 | build_classic_dir_vector (struct data_dependence_relation *ddr) | |
3566 | { | |
3567 | unsigned i, j; | |
3568 | lambda_vector dist_v; | |
86df10e3 | 3569 | |
9771b263 | 3570 | FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, dist_v) |
ba42e045 SP |
3571 | { |
3572 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
86df10e3 | 3573 | |
ba42e045 SP |
3574 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) |
3575 | dir_v[j] = dir_from_dist (dist_v[j]); | |
304afda6 | 3576 | |
ba42e045 SP |
3577 | save_dir_v (ddr, dir_v); |
3578 | } | |
56cf8686 SP |
3579 | } |
3580 | ||
ba42e045 SP |
3581 | /* Helper function. Returns true when there is a dependence between |
3582 | data references DRA and DRB. */ | |
0ff4040e | 3583 | |
ba42e045 SP |
3584 | static bool |
3585 | subscript_dependence_tester_1 (struct data_dependence_relation *ddr, | |
3586 | struct data_reference *dra, | |
da9a21f4 SP |
3587 | struct data_reference *drb, |
3588 | struct loop *loop_nest) | |
0ff4040e SP |
3589 | { |
3590 | unsigned int i; | |
0ff4040e | 3591 | tree last_conflicts; |
ebf78a47 | 3592 | struct subscript *subscript; |
9b00587c | 3593 | tree res = NULL_TREE; |
ba42e045 | 3594 | |
9771b263 | 3595 | for (i = 0; DDR_SUBSCRIPTS (ddr).iterate (i, &subscript); i++) |
0ff4040e | 3596 | { |
d93817c4 | 3597 | conflict_function *overlaps_a, *overlaps_b; |
ebf78a47 | 3598 | |
b8698a0f | 3599 | analyze_overlapping_iterations (DR_ACCESS_FN (dra, i), |
0ff4040e | 3600 | DR_ACCESS_FN (drb, i), |
b8698a0f | 3601 | &overlaps_a, &overlaps_b, |
da9a21f4 | 3602 | &last_conflicts, loop_nest); |
ebf78a47 | 3603 | |
9b00587c RG |
3604 | if (SUB_CONFLICTS_IN_A (subscript)) |
3605 | free_conflict_function (SUB_CONFLICTS_IN_A (subscript)); | |
3606 | if (SUB_CONFLICTS_IN_B (subscript)) | |
3607 | free_conflict_function (SUB_CONFLICTS_IN_B (subscript)); | |
3608 | ||
3609 | SUB_CONFLICTS_IN_A (subscript) = overlaps_a; | |
3610 | SUB_CONFLICTS_IN_B (subscript) = overlaps_b; | |
3611 | SUB_LAST_CONFLICT (subscript) = last_conflicts; | |
3612 | ||
3613 | /* If there is any undetermined conflict function we have to | |
3614 | give a conservative answer in case we cannot prove that | |
3615 | no dependence exists when analyzing another subscript. */ | |
d93817c4 ZD |
3616 | if (CF_NOT_KNOWN_P (overlaps_a) |
3617 | || CF_NOT_KNOWN_P (overlaps_b)) | |
0ff4040e | 3618 | { |
9b00587c RG |
3619 | res = chrec_dont_know; |
3620 | continue; | |
0ff4040e | 3621 | } |
ebf78a47 | 3622 | |
9b00587c | 3623 | /* When there is a subscript with no dependence we can stop. */ |
d93817c4 ZD |
3624 | else if (CF_NO_DEPENDENCE_P (overlaps_a) |
3625 | || CF_NO_DEPENDENCE_P (overlaps_b)) | |
0ff4040e | 3626 | { |
9b00587c RG |
3627 | res = chrec_known; |
3628 | break; | |
0ff4040e SP |
3629 | } |
3630 | } | |
3631 | ||
9b00587c RG |
3632 | if (res == NULL_TREE) |
3633 | return true; | |
3634 | ||
3635 | if (res == chrec_known) | |
3636 | dependence_stats.num_dependence_independent++; | |
3637 | else | |
3638 | dependence_stats.num_dependence_undetermined++; | |
3639 | finalize_ddr_dependent (ddr, res); | |
3640 | return false; | |
ba42e045 SP |
3641 | } |
3642 | ||
da9a21f4 | 3643 | /* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */ |
ba42e045 SP |
3644 | |
3645 | static void | |
da9a21f4 SP |
3646 | subscript_dependence_tester (struct data_dependence_relation *ddr, |
3647 | struct loop *loop_nest) | |
ba42e045 | 3648 | { |
da9a21f4 | 3649 | if (subscript_dependence_tester_1 (ddr, DDR_A (ddr), DDR_B (ddr), loop_nest)) |
ba42e045 | 3650 | dependence_stats.num_dependence_dependent++; |
0ff4040e | 3651 | |
0ff4040e | 3652 | compute_subscript_distance (ddr); |
da9a21f4 | 3653 | if (build_classic_dist_vector (ddr, loop_nest)) |
ba42e045 | 3654 | build_classic_dir_vector (ddr); |
0ff4040e SP |
3655 | } |
3656 | ||
56cf8686 | 3657 | /* Returns true when all the access functions of A are affine or |
da9a21f4 | 3658 | constant with respect to LOOP_NEST. */ |
56cf8686 | 3659 | |
b8698a0f | 3660 | static bool |
ed7a4b4b KG |
3661 | access_functions_are_affine_or_constant_p (const struct data_reference *a, |
3662 | const struct loop *loop_nest) | |
56cf8686 SP |
3663 | { |
3664 | unsigned int i; | |
9771b263 | 3665 | vec<tree> fns = DR_ACCESS_FNS (a); |
9cbb7989 | 3666 | tree t; |
3d8864c0 | 3667 | |
9771b263 | 3668 | FOR_EACH_VEC_ELT (fns, i, t) |
da9a21f4 SP |
3669 | if (!evolution_function_is_invariant_p (t, loop_nest->num) |
3670 | && !evolution_function_is_affine_multivariate_p (t, loop_nest->num)) | |
56cf8686 | 3671 | return false; |
b8698a0f | 3672 | |
56cf8686 SP |
3673 | return true; |
3674 | } | |
3675 | ||
3d8864c0 SP |
3676 | /* Initializes an equation for an OMEGA problem using the information |
3677 | contained in the ACCESS_FUN. Returns true when the operation | |
3678 | succeeded. | |
3679 | ||
3680 | PB is the omega constraint system. | |
3681 | EQ is the number of the equation to be initialized. | |
3682 | OFFSET is used for shifting the variables names in the constraints: | |
3683 | a constrain is composed of 2 * the number of variables surrounding | |
3684 | dependence accesses. OFFSET is set either to 0 for the first n variables, | |
3685 | then it is set to n. | |
3686 | ACCESS_FUN is expected to be an affine chrec. */ | |
3687 | ||
3688 | static bool | |
b8698a0f L |
3689 | init_omega_eq_with_af (omega_pb pb, unsigned eq, |
3690 | unsigned int offset, tree access_fun, | |
3d8864c0 SP |
3691 | struct data_dependence_relation *ddr) |
3692 | { | |
3693 | switch (TREE_CODE (access_fun)) | |
3694 | { | |
3695 | case POLYNOMIAL_CHREC: | |
3696 | { | |
3697 | tree left = CHREC_LEFT (access_fun); | |
3698 | tree right = CHREC_RIGHT (access_fun); | |
3699 | int var = CHREC_VARIABLE (access_fun); | |
3700 | unsigned var_idx; | |
3701 | ||
3702 | if (TREE_CODE (right) != INTEGER_CST) | |
3703 | return false; | |
3704 | ||
3705 | var_idx = index_in_loop_nest (var, DDR_LOOP_NEST (ddr)); | |
6b6fa4e9 | 3706 | pb->eqs[eq].coef[offset + var_idx + 1] = int_cst_value (right); |
3d8864c0 SP |
3707 | |
3708 | /* Compute the innermost loop index. */ | |
3709 | DDR_INNER_LOOP (ddr) = MAX (DDR_INNER_LOOP (ddr), var_idx); | |
3710 | ||
3711 | if (offset == 0) | |
b8698a0f | 3712 | pb->eqs[eq].coef[var_idx + DDR_NB_LOOPS (ddr) + 1] |
6b6fa4e9 | 3713 | += int_cst_value (right); |
3d8864c0 SP |
3714 | |
3715 | switch (TREE_CODE (left)) | |
3716 | { | |
3717 | case POLYNOMIAL_CHREC: | |
3718 | return init_omega_eq_with_af (pb, eq, offset, left, ddr); | |
3719 | ||
3720 | case INTEGER_CST: | |
6b6fa4e9 | 3721 | pb->eqs[eq].coef[0] += int_cst_value (left); |
3d8864c0 SP |
3722 | return true; |
3723 | ||
3724 | default: | |
3725 | return false; | |
3726 | } | |
3727 | } | |
3728 | ||
3729 | case INTEGER_CST: | |
6b6fa4e9 | 3730 | pb->eqs[eq].coef[0] += int_cst_value (access_fun); |
3d8864c0 SP |
3731 | return true; |
3732 | ||
3733 | default: | |
3734 | return false; | |
3735 | } | |
3736 | } | |
3737 | ||
3738 | /* As explained in the comments preceding init_omega_for_ddr, we have | |
3739 | to set up a system for each loop level, setting outer loops | |
3740 | variation to zero, and current loop variation to positive or zero. | |
3741 | Save each lexico positive distance vector. */ | |
3742 | ||
3743 | static void | |
3744 | omega_extract_distance_vectors (omega_pb pb, | |
3745 | struct data_dependence_relation *ddr) | |
3746 | { | |
3747 | int eq, geq; | |
3748 | unsigned i, j; | |
3749 | struct loop *loopi, *loopj; | |
3750 | enum omega_result res; | |
3751 | ||
3752 | /* Set a new problem for each loop in the nest. The basis is the | |
3753 | problem that we have initialized until now. On top of this we | |
3754 | add new constraints. */ | |
b8698a0f | 3755 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
9771b263 | 3756 | && DDR_LOOP_NEST (ddr).iterate (i, &loopi); i++) |
3d8864c0 SP |
3757 | { |
3758 | int dist = 0; | |
3759 | omega_pb copy = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), | |
3760 | DDR_NB_LOOPS (ddr)); | |
3761 | ||
3762 | omega_copy_problem (copy, pb); | |
3763 | ||
3764 | /* For all the outer loops "loop_j", add "dj = 0". */ | |
9771b263 | 3765 | for (j = 0; j < i && DDR_LOOP_NEST (ddr).iterate (j, &loopj); j++) |
3d8864c0 SP |
3766 | { |
3767 | eq = omega_add_zero_eq (copy, omega_black); | |
3768 | copy->eqs[eq].coef[j + 1] = 1; | |
3769 | } | |
3770 | ||
3771 | /* For "loop_i", add "0 <= di". */ | |
3772 | geq = omega_add_zero_geq (copy, omega_black); | |
3773 | copy->geqs[geq].coef[i + 1] = 1; | |
3774 | ||
3775 | /* Reduce the constraint system, and test that the current | |
3776 | problem is feasible. */ | |
3777 | res = omega_simplify_problem (copy); | |
b8698a0f | 3778 | if (res == omega_false |
3d8864c0 SP |
3779 | || res == omega_unknown |
3780 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3781 | goto next_problem; | |
3782 | ||
3783 | for (eq = 0; eq < copy->num_subs; eq++) | |
3784 | if (copy->subs[eq].key == (int) i + 1) | |
3785 | { | |
3786 | dist = copy->subs[eq].coef[0]; | |
3787 | goto found_dist; | |
3788 | } | |
3789 | ||
3790 | if (dist == 0) | |
3791 | { | |
3792 | /* Reinitialize problem... */ | |
3793 | omega_copy_problem (copy, pb); | |
9771b263 | 3794 | for (j = 0; j < i && DDR_LOOP_NEST (ddr).iterate (j, &loopj); j++) |
3d8864c0 SP |
3795 | { |
3796 | eq = omega_add_zero_eq (copy, omega_black); | |
3797 | copy->eqs[eq].coef[j + 1] = 1; | |
3798 | } | |
3799 | ||
3800 | /* ..., but this time "di = 1". */ | |
3801 | eq = omega_add_zero_eq (copy, omega_black); | |
3802 | copy->eqs[eq].coef[i + 1] = 1; | |
3803 | copy->eqs[eq].coef[0] = -1; | |
3804 | ||
3805 | res = omega_simplify_problem (copy); | |
b8698a0f | 3806 | if (res == omega_false |
3d8864c0 SP |
3807 | || res == omega_unknown |
3808 | || copy->num_geqs > (int) DDR_NB_LOOPS (ddr)) | |
3809 | goto next_problem; | |
3810 | ||
3811 | for (eq = 0; eq < copy->num_subs; eq++) | |
3812 | if (copy->subs[eq].key == (int) i + 1) | |
3813 | { | |
3814 | dist = copy->subs[eq].coef[0]; | |
3815 | goto found_dist; | |
3816 | } | |
3817 | } | |
3818 | ||
3819 | found_dist:; | |
3820 | /* Save the lexicographically positive distance vector. */ | |
3821 | if (dist >= 0) | |
3822 | { | |
3823 | lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3824 | lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
3825 | ||
3826 | dist_v[i] = dist; | |
3827 | ||
3828 | for (eq = 0; eq < copy->num_subs; eq++) | |
3829 | if (copy->subs[eq].key > 0) | |
3830 | { | |
3831 | dist = copy->subs[eq].coef[0]; | |
3832 | dist_v[copy->subs[eq].key - 1] = dist; | |
3833 | } | |
3834 | ||
3835 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
3836 | dir_v[j] = dir_from_dist (dist_v[j]); | |
3837 | ||
3838 | save_dist_v (ddr, dist_v); | |
3839 | save_dir_v (ddr, dir_v); | |
3840 | } | |
3841 | ||
3842 | next_problem:; | |
3843 | omega_free_problem (copy); | |
3844 | } | |
3845 | } | |
3846 | ||
3847 | /* This is called for each subscript of a tuple of data references: | |
3848 | insert an equality for representing the conflicts. */ | |
3849 | ||
3850 | static bool | |
3851 | omega_setup_subscript (tree access_fun_a, tree access_fun_b, | |
3852 | struct data_dependence_relation *ddr, | |
3853 | omega_pb pb, bool *maybe_dependent) | |
3854 | { | |
3855 | int eq; | |
33b30201 SP |
3856 | tree type = signed_type_for_types (TREE_TYPE (access_fun_a), |
3857 | TREE_TYPE (access_fun_b)); | |
726a989a RB |
3858 | tree fun_a = chrec_convert (type, access_fun_a, NULL); |
3859 | tree fun_b = chrec_convert (type, access_fun_b, NULL); | |
33b30201 | 3860 | tree difference = chrec_fold_minus (type, fun_a, fun_b); |
5a1f5f9a | 3861 | tree minus_one; |
3d8864c0 SP |
3862 | |
3863 | /* When the fun_a - fun_b is not constant, the dependence is not | |
3864 | captured by the classic distance vector representation. */ | |
3865 | if (TREE_CODE (difference) != INTEGER_CST) | |
3866 | return false; | |
3867 | ||
3868 | /* ZIV test. */ | |
3869 | if (ziv_subscript_p (fun_a, fun_b) && !integer_zerop (difference)) | |
3870 | { | |
3871 | /* There is no dependence. */ | |
3872 | *maybe_dependent = false; | |
3873 | return true; | |
3874 | } | |
3875 | ||
5a1f5f9a SP |
3876 | minus_one = build_int_cst (type, -1); |
3877 | fun_b = chrec_fold_multiply (type, fun_b, minus_one); | |
3d8864c0 SP |
3878 | |
3879 | eq = omega_add_zero_eq (pb, omega_black); | |
3880 | if (!init_omega_eq_with_af (pb, eq, DDR_NB_LOOPS (ddr), fun_a, ddr) | |
3881 | || !init_omega_eq_with_af (pb, eq, 0, fun_b, ddr)) | |
3882 | /* There is probably a dependence, but the system of | |
3883 | constraints cannot be built: answer "don't know". */ | |
3884 | return false; | |
3885 | ||
3886 | /* GCD test. */ | |
3887 | if (DDR_NB_LOOPS (ddr) != 0 && pb->eqs[eq].coef[0] | |
b8698a0f | 3888 | && !int_divides_p (lambda_vector_gcd |
3d8864c0 SP |
3889 | ((lambda_vector) &(pb->eqs[eq].coef[1]), |
3890 | 2 * DDR_NB_LOOPS (ddr)), | |
3891 | pb->eqs[eq].coef[0])) | |
3892 | { | |
3893 | /* There is no dependence. */ | |
3894 | *maybe_dependent = false; | |
3895 | return true; | |
3896 | } | |
3897 | ||
3898 | return true; | |
3899 | } | |
3900 | ||
3901 | /* Helper function, same as init_omega_for_ddr but specialized for | |
3902 | data references A and B. */ | |
3903 | ||
3904 | static bool | |
3905 | init_omega_for_ddr_1 (struct data_reference *dra, struct data_reference *drb, | |
3906 | struct data_dependence_relation *ddr, | |
3907 | omega_pb pb, bool *maybe_dependent) | |
3908 | { | |
3909 | unsigned i; | |
3910 | int ineq; | |
3911 | struct loop *loopi; | |
3912 | unsigned nb_loops = DDR_NB_LOOPS (ddr); | |
3913 | ||
3914 | /* Insert an equality per subscript. */ | |
3915 | for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) | |
3916 | { | |
3917 | if (!omega_setup_subscript (DR_ACCESS_FN (dra, i), DR_ACCESS_FN (drb, i), | |
3918 | ddr, pb, maybe_dependent)) | |
3919 | return false; | |
3920 | else if (*maybe_dependent == false) | |
3921 | { | |
3922 | /* There is no dependence. */ | |
3923 | DDR_ARE_DEPENDENT (ddr) = chrec_known; | |
3924 | return true; | |
3925 | } | |
3926 | } | |
3927 | ||
3928 | /* Insert inequalities: constraints corresponding to the iteration | |
3929 | domain, i.e. the loops surrounding the references "loop_x" and | |
3930 | the distance variables "dx". The layout of the OMEGA | |
3931 | representation is as follows: | |
3932 | - coef[0] is the constant | |
3933 | - coef[1..nb_loops] are the protected variables that will not be | |
3934 | removed by the solver: the "dx" | |
3935 | - coef[nb_loops + 1, 2*nb_loops] are the loop variables: "loop_x". | |
3936 | */ | |
b8698a0f | 3937 | for (i = 0; i <= DDR_INNER_LOOP (ddr) |
9771b263 | 3938 | && DDR_LOOP_NEST (ddr).iterate (i, &loopi); i++) |
3d8864c0 | 3939 | { |
652c4c71 | 3940 | HOST_WIDE_INT nbi = max_stmt_executions_int (loopi); |
3d8864c0 SP |
3941 | |
3942 | /* 0 <= loop_x */ | |
3943 | ineq = omega_add_zero_geq (pb, omega_black); | |
3944 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3945 | ||
3946 | /* 0 <= loop_x + dx */ | |
3947 | ineq = omega_add_zero_geq (pb, omega_black); | |
3948 | pb->geqs[ineq].coef[i + nb_loops + 1] = 1; | |
3949 | pb->geqs[ineq].coef[i + 1] = 1; | |
3950 | ||
3951 | if (nbi != -1) | |
3952 | { | |
3953 | /* loop_x <= nb_iters */ | |
3954 | ineq = omega_add_zero_geq (pb, omega_black); | |
3955 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3956 | pb->geqs[ineq].coef[0] = nbi; | |
3957 | ||
3958 | /* loop_x + dx <= nb_iters */ | |
3959 | ineq = omega_add_zero_geq (pb, omega_black); | |
3960 | pb->geqs[ineq].coef[i + nb_loops + 1] = -1; | |
3961 | pb->geqs[ineq].coef[i + 1] = -1; | |
3962 | pb->geqs[ineq].coef[0] = nbi; | |
3963 | ||
3964 | /* A step "dx" bigger than nb_iters is not feasible, so | |
3965 | add "0 <= nb_iters + dx", */ | |
3966 | ineq = omega_add_zero_geq (pb, omega_black); | |
3967 | pb->geqs[ineq].coef[i + 1] = 1; | |
3968 | pb->geqs[ineq].coef[0] = nbi; | |
3969 | /* and "dx <= nb_iters". */ | |
3970 | ineq = omega_add_zero_geq (pb, omega_black); | |
3971 | pb->geqs[ineq].coef[i + 1] = -1; | |
3972 | pb->geqs[ineq].coef[0] = nbi; | |
3973 | } | |
3974 | } | |
3975 | ||
3976 | omega_extract_distance_vectors (pb, ddr); | |
3977 | ||
3978 | return true; | |
3979 | } | |
3980 | ||
3981 | /* Sets up the Omega dependence problem for the data dependence | |
3982 | relation DDR. Returns false when the constraint system cannot be | |
3983 | built, ie. when the test answers "don't know". Returns true | |
3984 | otherwise, and when independence has been proved (using one of the | |
3985 | trivial dependence test), set MAYBE_DEPENDENT to false, otherwise | |
3986 | set MAYBE_DEPENDENT to true. | |
3987 | ||
3988 | Example: for setting up the dependence system corresponding to the | |
b8698a0f | 3989 | conflicting accesses |
3d8864c0 SP |
3990 | |
3991 | | loop_i | |
3992 | | loop_j | |
3993 | | A[i, i+1] = ... | |
3994 | | ... A[2*j, 2*(i + j)] | |
3995 | | endloop_j | |
3996 | | endloop_i | |
b8698a0f | 3997 | |
3d8864c0 SP |
3998 | the following constraints come from the iteration domain: |
3999 | ||
4000 | 0 <= i <= Ni | |
4001 | 0 <= i + di <= Ni | |
4002 | 0 <= j <= Nj | |
4003 | 0 <= j + dj <= Nj | |
4004 | ||
4005 | where di, dj are the distance variables. The constraints | |
4006 | representing the conflicting elements are: | |
4007 | ||
4008 | i = 2 * (j + dj) | |
4009 | i + 1 = 2 * (i + di + j + dj) | |
4010 | ||
4011 | For asking that the resulting distance vector (di, dj) be | |
4012 | lexicographically positive, we insert the constraint "di >= 0". If | |
4013 | "di = 0" in the solution, we fix that component to zero, and we | |
4014 | look at the inner loops: we set a new problem where all the outer | |
4015 | loop distances are zero, and fix this inner component to be | |
4016 | positive. When one of the components is positive, we save that | |
4017 | distance, and set a new problem where the distance on this loop is | |
4018 | zero, searching for other distances in the inner loops. Here is | |
4019 | the classic example that illustrates that we have to set for each | |
4020 | inner loop a new problem: | |
4021 | ||
4022 | | loop_1 | |
4023 | | loop_2 | |
4024 | | A[10] | |
4025 | | endloop_2 | |
4026 | | endloop_1 | |
4027 | ||
4028 | we have to save two distances (1, 0) and (0, 1). | |
4029 | ||
4030 | Given two array references, refA and refB, we have to set the | |
4031 | dependence problem twice, refA vs. refB and refB vs. refA, and we | |
4032 | cannot do a single test, as refB might occur before refA in the | |
4033 | inner loops, and the contrary when considering outer loops: ex. | |
4034 | ||
4035 | | loop_0 | |
4036 | | loop_1 | |
4037 | | loop_2 | |
4038 | | T[{1,+,1}_2][{1,+,1}_1] // refA | |
4039 | | T[{2,+,1}_2][{0,+,1}_1] // refB | |
4040 | | endloop_2 | |
4041 | | endloop_1 | |
4042 | | endloop_0 | |
4043 | ||
4044 | refB touches the elements in T before refA, and thus for the same | |
4045 | loop_0 refB precedes refA: ie. the distance vector (0, 1, -1) | |
4046 | but for successive loop_0 iterations, we have (1, -1, 1) | |
4047 | ||
4048 | The Omega solver expects the distance variables ("di" in the | |
4049 | previous example) to come first in the constraint system (as | |
4050 | variables to be protected, or "safe" variables), the constraint | |
4051 | system is built using the following layout: | |
4052 | ||
4053 | "cst | distance vars | index vars". | |
4054 | */ | |
4055 | ||
4056 | static bool | |
4057 | init_omega_for_ddr (struct data_dependence_relation *ddr, | |
4058 | bool *maybe_dependent) | |
4059 | { | |
4060 | omega_pb pb; | |
4061 | bool res = false; | |
4062 | ||
4063 | *maybe_dependent = true; | |
4064 | ||
4065 | if (same_access_functions (ddr)) | |
4066 | { | |
4067 | unsigned j; | |
4068 | lambda_vector dir_v; | |
4069 | ||
4070 | /* Save the 0 vector. */ | |
4071 | save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); | |
4072 | dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); | |
4073 | for (j = 0; j < DDR_NB_LOOPS (ddr); j++) | |
4074 | dir_v[j] = dir_equal; | |
4075 | save_dir_v (ddr, dir_v); | |
4076 | ||
4077 | /* Save the dependences carried by outer loops. */ | |
4078 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4079 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
4080 | maybe_dependent); | |
4081 | omega_free_problem (pb); | |
4082 | return res; | |
4083 | } | |
4084 | ||
4085 | /* Omega expects the protected variables (those that have to be kept | |
4086 | after elimination) to appear first in the constraint system. | |
4087 | These variables are the distance variables. In the following | |
4088 | initialization we declare NB_LOOPS safe variables, and the total | |
4089 | number of variables for the constraint system is 2*NB_LOOPS. */ | |
4090 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4091 | res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb, | |
4092 | maybe_dependent); | |
4093 | omega_free_problem (pb); | |
4094 | ||
4095 | /* Stop computation if not decidable, or no dependence. */ | |
4096 | if (res == false || *maybe_dependent == false) | |
4097 | return res; | |
4098 | ||
4099 | pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr)); | |
4100 | res = init_omega_for_ddr_1 (DDR_B (ddr), DDR_A (ddr), ddr, pb, | |
4101 | maybe_dependent); | |
4102 | omega_free_problem (pb); | |
4103 | ||
4104 | return res; | |
4105 | } | |
4106 | ||
4107 | /* Return true when DDR contains the same information as that stored | |
4108 | in DIR_VECTS and in DIST_VECTS, return false otherwise. */ | |
4109 | ||
4110 | static bool | |
4111 | ddr_consistent_p (FILE *file, | |
4112 | struct data_dependence_relation *ddr, | |
9771b263 DN |
4113 | vec<lambda_vector> dist_vects, |
4114 | vec<lambda_vector> dir_vects) | |
3d8864c0 SP |
4115 | { |
4116 | unsigned int i, j; | |
4117 | ||
4118 | /* If dump_file is set, output there. */ | |
4119 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4120 | file = dump_file; | |
4121 | ||
9771b263 | 4122 | if (dist_vects.length () != DDR_NUM_DIST_VECTS (ddr)) |
3d8864c0 SP |
4123 | { |
4124 | lambda_vector b_dist_v; | |
4125 | fprintf (file, "\n(Number of distance vectors differ: Banerjee has %d, Omega has %d.\n", | |
9771b263 | 4126 | dist_vects.length (), |
3d8864c0 SP |
4127 | DDR_NUM_DIST_VECTS (ddr)); |
4128 | ||
4129 | fprintf (file, "Banerjee dist vectors:\n"); | |
9771b263 | 4130 | FOR_EACH_VEC_ELT (dist_vects, i, b_dist_v) |
3d8864c0 SP |
4131 | print_lambda_vector (file, b_dist_v, DDR_NB_LOOPS (ddr)); |
4132 | ||
4133 | fprintf (file, "Omega dist vectors:\n"); | |
4134 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
4135 | print_lambda_vector (file, DDR_DIST_VECT (ddr, i), DDR_NB_LOOPS (ddr)); | |
4136 | ||
4137 | fprintf (file, "data dependence relation:\n"); | |
4138 | dump_data_dependence_relation (file, ddr); | |
4139 | ||
4140 | fprintf (file, ")\n"); | |
4141 | return false; | |
4142 | } | |
4143 | ||
9771b263 | 4144 | if (dir_vects.length () != DDR_NUM_DIR_VECTS (ddr)) |
3d8864c0 SP |
4145 | { |
4146 | fprintf (file, "\n(Number of direction vectors differ: Banerjee has %d, Omega has %d.)\n", | |
9771b263 | 4147 | dir_vects.length (), |
3d8864c0 SP |
4148 | DDR_NUM_DIR_VECTS (ddr)); |
4149 | return false; | |
4150 | } | |
4151 | ||
4152 | for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) | |
4153 | { | |
4154 | lambda_vector a_dist_v; | |
4155 | lambda_vector b_dist_v = DDR_DIST_VECT (ddr, i); | |
4156 | ||
4157 | /* Distance vectors are not ordered in the same way in the DDR | |
4158 | and in the DIST_VECTS: search for a matching vector. */ | |
9771b263 | 4159 | FOR_EACH_VEC_ELT (dist_vects, j, a_dist_v) |
3d8864c0 SP |
4160 | if (lambda_vector_equal (a_dist_v, b_dist_v, DDR_NB_LOOPS (ddr))) |
4161 | break; | |
4162 | ||
9771b263 | 4163 | if (j == dist_vects.length ()) |
3d8864c0 SP |
4164 | { |
4165 | fprintf (file, "\n(Dist vectors from the first dependence analyzer:\n"); | |
4166 | print_dist_vectors (file, dist_vects, DDR_NB_LOOPS (ddr)); | |
4167 | fprintf (file, "not found in Omega dist vectors:\n"); | |
4168 | print_dist_vectors (file, DDR_DIST_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4169 | fprintf (file, "data dependence relation:\n"); | |
4170 | dump_data_dependence_relation (file, ddr); | |
4171 | fprintf (file, ")\n"); | |
4172 | } | |
4173 | } | |
4174 | ||
4175 | for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) | |
4176 | { | |
4177 | lambda_vector a_dir_v; | |
4178 | lambda_vector b_dir_v = DDR_DIR_VECT (ddr, i); | |
4179 | ||
4180 | /* Direction vectors are not ordered in the same way in the DDR | |
4181 | and in the DIR_VECTS: search for a matching vector. */ | |
9771b263 | 4182 | FOR_EACH_VEC_ELT (dir_vects, j, a_dir_v) |
3d8864c0 SP |
4183 | if (lambda_vector_equal (a_dir_v, b_dir_v, DDR_NB_LOOPS (ddr))) |
4184 | break; | |
4185 | ||
9771b263 | 4186 | if (j == dist_vects.length ()) |
3d8864c0 SP |
4187 | { |
4188 | fprintf (file, "\n(Dir vectors from the first dependence analyzer:\n"); | |
4189 | print_dir_vectors (file, dir_vects, DDR_NB_LOOPS (ddr)); | |
4190 | fprintf (file, "not found in Omega dir vectors:\n"); | |
4191 | print_dir_vectors (file, DDR_DIR_VECTS (ddr), DDR_NB_LOOPS (ddr)); | |
4192 | fprintf (file, "data dependence relation:\n"); | |
4193 | dump_data_dependence_relation (file, ddr); | |
4194 | fprintf (file, ")\n"); | |
4195 | } | |
4196 | } | |
4197 | ||
b8698a0f | 4198 | return true; |
3d8864c0 SP |
4199 | } |
4200 | ||
da9a21f4 SP |
4201 | /* This computes the affine dependence relation between A and B with |
4202 | respect to LOOP_NEST. CHREC_KNOWN is used for representing the | |
4203 | independence between two accesses, while CHREC_DONT_KNOW is used | |
4204 | for representing the unknown relation. | |
b8698a0f | 4205 | |
56cf8686 SP |
4206 | Note that it is possible to stop the computation of the dependence |
4207 | relation the first time we detect a CHREC_KNOWN element for a given | |
4208 | subscript. */ | |
4209 | ||
f20132e7 | 4210 | void |
da9a21f4 SP |
4211 | compute_affine_dependence (struct data_dependence_relation *ddr, |
4212 | struct loop *loop_nest) | |
56cf8686 SP |
4213 | { |
4214 | struct data_reference *dra = DDR_A (ddr); | |
4215 | struct data_reference *drb = DDR_B (ddr); | |
b8698a0f | 4216 | |
56cf8686 SP |
4217 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4218 | { | |
36d59cf7 | 4219 | fprintf (dump_file, "(compute_affine_dependence\n"); |
c4ddde1b RG |
4220 | fprintf (dump_file, " stmt_a: "); |
4221 | print_gimple_stmt (dump_file, DR_STMT (dra), 0, TDF_SLIM); | |
4222 | fprintf (dump_file, " stmt_b: "); | |
4223 | print_gimple_stmt (dump_file, DR_STMT (drb), 0, TDF_SLIM); | |
56cf8686 | 4224 | } |
0ff4040e | 4225 | |
56cf8686 | 4226 | /* Analyze only when the dependence relation is not yet known. */ |
1a4571cb | 4227 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) |
56cf8686 | 4228 | { |
0ff4040e SP |
4229 | dependence_stats.num_dependence_tests++; |
4230 | ||
da9a21f4 SP |
4231 | if (access_functions_are_affine_or_constant_p (dra, loop_nest) |
4232 | && access_functions_are_affine_or_constant_p (drb, loop_nest)) | |
3d8864c0 | 4233 | { |
bcf1ef00 RB |
4234 | subscript_dependence_tester (ddr, loop_nest); |
4235 | ||
3d8864c0 SP |
4236 | if (flag_check_data_deps) |
4237 | { | |
bcf1ef00 | 4238 | /* Dump the dependences from the first algorithm. */ |
3d8864c0 SP |
4239 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4240 | { | |
4241 | fprintf (dump_file, "\n\nBanerjee Analyzer\n"); | |
4242 | dump_data_dependence_relation (dump_file, ddr); | |
4243 | } | |
4244 | ||
4245 | if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
4246 | { | |
4247 | bool maybe_dependent; | |
9771b263 | 4248 | vec<lambda_vector> dir_vects, dist_vects; |
3d8864c0 SP |
4249 | |
4250 | /* Save the result of the first DD analyzer. */ | |
4251 | dist_vects = DDR_DIST_VECTS (ddr); | |
4252 | dir_vects = DDR_DIR_VECTS (ddr); | |
4253 | ||
4254 | /* Reset the information. */ | |
9771b263 DN |
4255 | DDR_DIST_VECTS (ddr).create (0); |
4256 | DDR_DIR_VECTS (ddr).create (0); | |
3d8864c0 SP |
4257 | |
4258 | /* Compute the same information using Omega. */ | |
4259 | if (!init_omega_for_ddr (ddr, &maybe_dependent)) | |
4260 | goto csys_dont_know; | |
4261 | ||
4262 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4263 | { | |
4264 | fprintf (dump_file, "Omega Analyzer\n"); | |
4265 | dump_data_dependence_relation (dump_file, ddr); | |
4266 | } | |
4267 | ||
4268 | /* Check that we get the same information. */ | |
4269 | if (maybe_dependent) | |
4270 | gcc_assert (ddr_consistent_p (stderr, ddr, dist_vects, | |
4271 | dir_vects)); | |
4272 | } | |
4273 | } | |
3d8864c0 | 4274 | } |
b8698a0f | 4275 | |
56cf8686 SP |
4276 | /* As a last case, if the dependence cannot be determined, or if |
4277 | the dependence is considered too difficult to determine, answer | |
4278 | "don't know". */ | |
4279 | else | |
0ff4040e | 4280 | { |
3d8864c0 | 4281 | csys_dont_know:; |
0ff4040e SP |
4282 | dependence_stats.num_dependence_undetermined++; |
4283 | ||
4284 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4285 | { | |
4286 | fprintf (dump_file, "Data ref a:\n"); | |
4287 | dump_data_reference (dump_file, dra); | |
4288 | fprintf (dump_file, "Data ref b:\n"); | |
4289 | dump_data_reference (dump_file, drb); | |
4290 | fprintf (dump_file, "affine dependence test not usable: access function not affine or constant.\n"); | |
4291 | } | |
4292 | finalize_ddr_dependent (ddr, chrec_dont_know); | |
4293 | } | |
56cf8686 | 4294 | } |
b8698a0f | 4295 | |
56cf8686 | 4296 | if (dump_file && (dump_flags & TDF_DETAILS)) |
c4ddde1b RG |
4297 | { |
4298 | if (DDR_ARE_DEPENDENT (ddr) == chrec_known) | |
4299 | fprintf (dump_file, ") -> no dependence\n"); | |
4300 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) | |
4301 | fprintf (dump_file, ") -> dependence analysis failed\n"); | |
4302 | else | |
4303 | fprintf (dump_file, ")\n"); | |
4304 | } | |
56cf8686 SP |
4305 | } |
4306 | ||
ba42e045 SP |
4307 | /* Compute in DEPENDENCE_RELATIONS the data dependence graph for all |
4308 | the data references in DATAREFS, in the LOOP_NEST. When | |
ebf78a47 | 4309 | COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self |
3881dee9 AB |
4310 | relations. Return true when successful, i.e. data references number |
4311 | is small enough to be handled. */ | |
56cf8686 | 4312 | |
3881dee9 | 4313 | bool |
9771b263 DN |
4314 | compute_all_dependences (vec<data_reference_p> datarefs, |
4315 | vec<ddr_p> *dependence_relations, | |
4316 | vec<loop_p> loop_nest, | |
ebf78a47 | 4317 | bool compute_self_and_rr) |
56cf8686 | 4318 | { |
ebf78a47 SP |
4319 | struct data_dependence_relation *ddr; |
4320 | struct data_reference *a, *b; | |
4321 | unsigned int i, j; | |
56cf8686 | 4322 | |
9771b263 | 4323 | if ((int) datarefs.length () |
3881dee9 AB |
4324 | > PARAM_VALUE (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS)) |
4325 | { | |
4326 | struct data_dependence_relation *ddr; | |
4327 | ||
4328 | /* Insert a single relation into dependence_relations: | |
4329 | chrec_dont_know. */ | |
4330 | ddr = initialize_data_dependence_relation (NULL, NULL, loop_nest); | |
9771b263 | 4331 | dependence_relations->safe_push (ddr); |
3881dee9 AB |
4332 | return false; |
4333 | } | |
4334 | ||
9771b263 DN |
4335 | FOR_EACH_VEC_ELT (datarefs, i, a) |
4336 | for (j = i + 1; datarefs.iterate (j, &b); j++) | |
b0af49c4 | 4337 | if (DR_IS_WRITE (a) || DR_IS_WRITE (b) || compute_self_and_rr) |
ebf78a47 SP |
4338 | { |
4339 | ddr = initialize_data_dependence_relation (a, b, loop_nest); | |
9771b263 DN |
4340 | dependence_relations->safe_push (ddr); |
4341 | if (loop_nest.exists ()) | |
4342 | compute_affine_dependence (ddr, loop_nest[0]); | |
ebf78a47 | 4343 | } |
789246d7 | 4344 | |
ebf78a47 | 4345 | if (compute_self_and_rr) |
9771b263 | 4346 | FOR_EACH_VEC_ELT (datarefs, i, a) |
56cf8686 | 4347 | { |
ebf78a47 | 4348 | ddr = initialize_data_dependence_relation (a, a, loop_nest); |
9771b263 DN |
4349 | dependence_relations->safe_push (ddr); |
4350 | if (loop_nest.exists ()) | |
4351 | compute_affine_dependence (ddr, loop_nest[0]); | |
56cf8686 | 4352 | } |
3881dee9 AB |
4353 | |
4354 | return true; | |
56cf8686 SP |
4355 | } |
4356 | ||
aeb83f09 RG |
4357 | /* Describes a location of a memory reference. */ |
4358 | ||
4359 | typedef struct data_ref_loc_d | |
4360 | { | |
a3698dfc JJ |
4361 | /* The memory reference. */ |
4362 | tree ref; | |
aeb83f09 | 4363 | |
fcac74a1 RB |
4364 | /* True if the memory reference is read. */ |
4365 | bool is_read; | |
aeb83f09 RG |
4366 | } data_ref_loc; |
4367 | ||
aeb83f09 | 4368 | |
946e1bc7 ZD |
4369 | /* Stores the locations of memory references in STMT to REFERENCES. Returns |
4370 | true if STMT clobbers memory, false otherwise. */ | |
4371 | ||
aeb83f09 | 4372 | static bool |
ff4c81cc | 4373 | get_references_in_stmt (gimple stmt, vec<data_ref_loc, va_heap> *references) |
946e1bc7 ZD |
4374 | { |
4375 | bool clobbers_memory = false; | |
f32682ca | 4376 | data_ref_loc ref; |
a3698dfc | 4377 | tree op0, op1; |
726a989a | 4378 | enum gimple_code stmt_code = gimple_code (stmt); |
946e1bc7 | 4379 | |
946e1bc7 | 4380 | /* ASM_EXPR and CALL_EXPR may embed arbitrary side effects. |
f2ea3c15 RG |
4381 | As we cannot model data-references to not spelled out |
4382 | accesses give up if they may occur. */ | |
74bf76ed JJ |
4383 | if (stmt_code == GIMPLE_CALL |
4384 | && !(gimple_call_flags (stmt) & ECF_CONST)) | |
4385 | { | |
4386 | /* Allow IFN_GOMP_SIMD_LANE in their own loops. */ | |
5ce9450f JJ |
4387 | if (gimple_call_internal_p (stmt)) |
4388 | switch (gimple_call_internal_fn (stmt)) | |
4389 | { | |
4390 | case IFN_GOMP_SIMD_LANE: | |
4391 | { | |
4392 | struct loop *loop = gimple_bb (stmt)->loop_father; | |
4393 | tree uid = gimple_call_arg (stmt, 0); | |
4394 | gcc_assert (TREE_CODE (uid) == SSA_NAME); | |
4395 | if (loop == NULL | |
4396 | || loop->simduid != SSA_NAME_VAR (uid)) | |
4397 | clobbers_memory = true; | |
4398 | break; | |
4399 | } | |
4400 | case IFN_MASK_LOAD: | |
4401 | case IFN_MASK_STORE: | |
4402 | break; | |
4403 | default: | |
74bf76ed | 4404 | clobbers_memory = true; |
5ce9450f JJ |
4405 | break; |
4406 | } | |
74bf76ed JJ |
4407 | else |
4408 | clobbers_memory = true; | |
4409 | } | |
4410 | else if (stmt_code == GIMPLE_ASM | |
538dd0b7 DM |
4411 | && (gimple_asm_volatile_p (as_a <gasm *> (stmt)) |
4412 | || gimple_vuse (stmt))) | |
946e1bc7 ZD |
4413 | clobbers_memory = true; |
4414 | ||
5006671f | 4415 | if (!gimple_vuse (stmt)) |
946e1bc7 ZD |
4416 | return clobbers_memory; |
4417 | ||
726a989a | 4418 | if (stmt_code == GIMPLE_ASSIGN) |
946e1bc7 | 4419 | { |
c8ae0bec | 4420 | tree base; |
a3698dfc JJ |
4421 | op0 = gimple_assign_lhs (stmt); |
4422 | op1 = gimple_assign_rhs1 (stmt); | |
b8698a0f | 4423 | |
a3698dfc JJ |
4424 | if (DECL_P (op1) |
4425 | || (REFERENCE_CLASS_P (op1) | |
4426 | && (base = get_base_address (op1)) | |
c8ae0bec | 4427 | && TREE_CODE (base) != SSA_NAME)) |
946e1bc7 | 4428 | { |
a3698dfc | 4429 | ref.ref = op1; |
f32682ca | 4430 | ref.is_read = true; |
9771b263 | 4431 | references->safe_push (ref); |
946e1bc7 | 4432 | } |
946e1bc7 | 4433 | } |
726a989a | 4434 | else if (stmt_code == GIMPLE_CALL) |
946e1bc7 | 4435 | { |
1b14d815 | 4436 | unsigned i, n; |
ac84e05e | 4437 | |
5ce9450f JJ |
4438 | ref.is_read = false; |
4439 | if (gimple_call_internal_p (stmt)) | |
4440 | switch (gimple_call_internal_fn (stmt)) | |
4441 | { | |
4442 | case IFN_MASK_LOAD: | |
8e91d222 JJ |
4443 | if (gimple_call_lhs (stmt) == NULL_TREE) |
4444 | break; | |
5ce9450f JJ |
4445 | ref.is_read = true; |
4446 | case IFN_MASK_STORE: | |
4447 | ref.ref = fold_build2 (MEM_REF, | |
4448 | ref.is_read | |
4449 | ? TREE_TYPE (gimple_call_lhs (stmt)) | |
4450 | : TREE_TYPE (gimple_call_arg (stmt, 3)), | |
4451 | gimple_call_arg (stmt, 0), | |
4452 | gimple_call_arg (stmt, 1)); | |
4453 | references->safe_push (ref); | |
4454 | return false; | |
4455 | default: | |
4456 | break; | |
4457 | } | |
4458 | ||
a3698dfc | 4459 | op0 = gimple_call_lhs (stmt); |
1b14d815 | 4460 | n = gimple_call_num_args (stmt); |
ac84e05e | 4461 | for (i = 0; i < n; i++) |
946e1bc7 | 4462 | { |
a3698dfc | 4463 | op1 = gimple_call_arg (stmt, i); |
ac84e05e | 4464 | |
a3698dfc JJ |
4465 | if (DECL_P (op1) |
4466 | || (REFERENCE_CLASS_P (op1) && get_base_address (op1))) | |
946e1bc7 | 4467 | { |
a3698dfc | 4468 | ref.ref = op1; |
f32682ca | 4469 | ref.is_read = true; |
9771b263 | 4470 | references->safe_push (ref); |
946e1bc7 ZD |
4471 | } |
4472 | } | |
4473 | } | |
1b14d815 RS |
4474 | else |
4475 | return clobbers_memory; | |
946e1bc7 | 4476 | |
a3698dfc JJ |
4477 | if (op0 |
4478 | && (DECL_P (op0) | |
4479 | || (REFERENCE_CLASS_P (op0) && get_base_address (op0)))) | |
1b14d815 | 4480 | { |
a3698dfc | 4481 | ref.ref = op0; |
f32682ca | 4482 | ref.is_read = false; |
9771b263 | 4483 | references->safe_push (ref); |
1b14d815 | 4484 | } |
946e1bc7 ZD |
4485 | return clobbers_memory; |
4486 | } | |
4487 | ||
4488 | /* Stores the data references in STMT to DATAREFS. If there is an unanalyzable | |
3cb960c7 | 4489 | reference, returns false, otherwise returns true. NEST is the outermost |
f8bf9252 | 4490 | loop of the loop nest in which the references should be analyzed. */ |
946e1bc7 | 4491 | |
f8bf9252 | 4492 | bool |
726a989a | 4493 | find_data_references_in_stmt (struct loop *nest, gimple stmt, |
9771b263 | 4494 | vec<data_reference_p> *datarefs) |
946e1bc7 ZD |
4495 | { |
4496 | unsigned i; | |
00f96dc9 | 4497 | auto_vec<data_ref_loc, 2> references; |
946e1bc7 ZD |
4498 | data_ref_loc *ref; |
4499 | bool ret = true; | |
4500 | data_reference_p dr; | |
4501 | ||
4502 | if (get_references_in_stmt (stmt, &references)) | |
ff4c81cc | 4503 | return false; |
946e1bc7 | 4504 | |
9771b263 | 4505 | FOR_EACH_VEC_ELT (references, i, ref) |
946e1bc7 | 4506 | { |
5c640e29 | 4507 | dr = create_data_ref (nest, loop_containing_stmt (stmt), |
a3698dfc | 4508 | ref->ref, stmt, ref->is_read); |
bbc8a8dc | 4509 | gcc_assert (dr != NULL); |
9771b263 | 4510 | datarefs->safe_push (dr); |
946e1bc7 | 4511 | } |
9771b263 | 4512 | references.release (); |
946e1bc7 ZD |
4513 | return ret; |
4514 | } | |
4515 | ||
5c640e29 SP |
4516 | /* Stores the data references in STMT to DATAREFS. If there is an |
4517 | unanalyzable reference, returns false, otherwise returns true. | |
4518 | NEST is the outermost loop of the loop nest in which the references | |
4519 | should be instantiated, LOOP is the loop in which the references | |
4520 | should be analyzed. */ | |
ed91d661 SP |
4521 | |
4522 | bool | |
5c640e29 | 4523 | graphite_find_data_references_in_stmt (loop_p nest, loop_p loop, gimple stmt, |
9771b263 | 4524 | vec<data_reference_p> *datarefs) |
ed91d661 SP |
4525 | { |
4526 | unsigned i; | |
00f96dc9 | 4527 | auto_vec<data_ref_loc, 2> references; |
ed91d661 SP |
4528 | data_ref_loc *ref; |
4529 | bool ret = true; | |
4530 | data_reference_p dr; | |
4531 | ||
4532 | if (get_references_in_stmt (stmt, &references)) | |
ff4c81cc | 4533 | return false; |
ed91d661 | 4534 | |
9771b263 | 4535 | FOR_EACH_VEC_ELT (references, i, ref) |
ed91d661 | 4536 | { |
a3698dfc | 4537 | dr = create_data_ref (nest, loop, ref->ref, stmt, ref->is_read); |
ed91d661 | 4538 | gcc_assert (dr != NULL); |
9771b263 | 4539 | datarefs->safe_push (dr); |
ed91d661 SP |
4540 | } |
4541 | ||
9771b263 | 4542 | references.release (); |
ed91d661 SP |
4543 | return ret; |
4544 | } | |
4545 | ||
a70d6342 IR |
4546 | /* Search the data references in LOOP, and record the information into |
4547 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4548 | difficult case, returns NULL_TREE otherwise. */ | |
4549 | ||
bfe068c3 | 4550 | tree |
a70d6342 | 4551 | find_data_references_in_bb (struct loop *loop, basic_block bb, |
9771b263 | 4552 | vec<data_reference_p> *datarefs) |
a70d6342 IR |
4553 | { |
4554 | gimple_stmt_iterator bsi; | |
4555 | ||
4556 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
4557 | { | |
4558 | gimple stmt = gsi_stmt (bsi); | |
4559 | ||
4560 | if (!find_data_references_in_stmt (loop, stmt, datarefs)) | |
4561 | { | |
4562 | struct data_reference *res; | |
4563 | res = XCNEW (struct data_reference); | |
9771b263 | 4564 | datarefs->safe_push (res); |
a70d6342 IR |
4565 | |
4566 | return chrec_dont_know; | |
4567 | } | |
4568 | } | |
4569 | ||
4570 | return NULL_TREE; | |
4571 | } | |
4572 | ||
56cf8686 SP |
4573 | /* Search the data references in LOOP, and record the information into |
4574 | DATAREFS. Returns chrec_dont_know when failing to analyze a | |
4575 | difficult case, returns NULL_TREE otherwise. | |
3cb960c7 | 4576 | |
464f49d8 DB |
4577 | TODO: This function should be made smarter so that it can handle address |
4578 | arithmetic as if they were array accesses, etc. */ | |
56cf8686 | 4579 | |
fcac74a1 | 4580 | tree |
ebf78a47 | 4581 | find_data_references_in_loop (struct loop *loop, |
9771b263 | 4582 | vec<data_reference_p> *datarefs) |
56cf8686 | 4583 | { |
ccbdbf0a JL |
4584 | basic_block bb, *bbs; |
4585 | unsigned int i; | |
86df10e3 | 4586 | |
bbc8a8dc | 4587 | bbs = get_loop_body_in_dom_order (loop); |
ccbdbf0a JL |
4588 | |
4589 | for (i = 0; i < loop->num_nodes; i++) | |
56cf8686 | 4590 | { |
ccbdbf0a JL |
4591 | bb = bbs[i]; |
4592 | ||
a70d6342 IR |
4593 | if (find_data_references_in_bb (loop, bb, datarefs) == chrec_dont_know) |
4594 | { | |
4595 | free (bbs); | |
4596 | return chrec_dont_know; | |
4597 | } | |
56cf8686 | 4598 | } |
ccbdbf0a JL |
4599 | free (bbs); |
4600 | ||
4aad410d | 4601 | return NULL_TREE; |
56cf8686 SP |
4602 | } |
4603 | ||
ba42e045 SP |
4604 | /* Recursive helper function. */ |
4605 | ||
4606 | static bool | |
9771b263 | 4607 | find_loop_nest_1 (struct loop *loop, vec<loop_p> *loop_nest) |
ba42e045 SP |
4608 | { |
4609 | /* Inner loops of the nest should not contain siblings. Example: | |
4610 | when there are two consecutive loops, | |
4611 | ||
4612 | | loop_0 | |
4613 | | loop_1 | |
4614 | | A[{0, +, 1}_1] | |
4615 | | endloop_1 | |
4616 | | loop_2 | |
4617 | | A[{0, +, 1}_2] | |
4618 | | endloop_2 | |
4619 | | endloop_0 | |
4620 | ||
4621 | the dependence relation cannot be captured by the distance | |
4622 | abstraction. */ | |
4623 | if (loop->next) | |
4624 | return false; | |
56cf8686 | 4625 | |
9771b263 | 4626 | loop_nest->safe_push (loop); |
ba42e045 SP |
4627 | if (loop->inner) |
4628 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4629 | return true; | |
4630 | } | |
4631 | ||
4632 | /* Return false when the LOOP is not well nested. Otherwise return | |
4633 | true and insert in LOOP_NEST the loops of the nest. LOOP_NEST will | |
4634 | contain the loops from the outermost to the innermost, as they will | |
4635 | appear in the classic distance vector. */ | |
4636 | ||
5417e022 | 4637 | bool |
9771b263 | 4638 | find_loop_nest (struct loop *loop, vec<loop_p> *loop_nest) |
ba42e045 | 4639 | { |
9771b263 | 4640 | loop_nest->safe_push (loop); |
ba42e045 SP |
4641 | if (loop->inner) |
4642 | return find_loop_nest_1 (loop->inner, loop_nest); | |
4643 | return true; | |
4644 | } | |
56cf8686 | 4645 | |
9f275479 JS |
4646 | /* Returns true when the data dependences have been computed, false otherwise. |
4647 | Given a loop nest LOOP, the following vectors are returned: | |
b8698a0f L |
4648 | DATAREFS is initialized to all the array elements contained in this loop, |
4649 | DEPENDENCE_RELATIONS contains the relations between the data references. | |
4650 | Compute read-read and self relations if | |
86a07404 | 4651 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ |
56cf8686 | 4652 | |
9f275479 | 4653 | bool |
b8698a0f | 4654 | compute_data_dependences_for_loop (struct loop *loop, |
86a07404 | 4655 | bool compute_self_and_read_read_dependences, |
9771b263 DN |
4656 | vec<loop_p> *loop_nest, |
4657 | vec<data_reference_p> *datarefs, | |
4658 | vec<ddr_p> *dependence_relations) | |
56cf8686 | 4659 | { |
9f275479 | 4660 | bool res = true; |
86a07404 | 4661 | |
0ff4040e | 4662 | memset (&dependence_stats, 0, sizeof (dependence_stats)); |
56cf8686 | 4663 | |
b8698a0f | 4664 | /* If the loop nest is not well formed, or one of the data references |
ba42e045 SP |
4665 | is not computable, give up without spending time to compute other |
4666 | dependences. */ | |
3cb960c7 | 4667 | if (!loop |
01be8516 | 4668 | || !find_loop_nest (loop, loop_nest) |
3881dee9 AB |
4669 | || find_data_references_in_loop (loop, datarefs) == chrec_dont_know |
4670 | || !compute_all_dependences (*datarefs, dependence_relations, *loop_nest, | |
4671 | compute_self_and_read_read_dependences)) | |
4672 | res = false; | |
0ff4040e SP |
4673 | |
4674 | if (dump_file && (dump_flags & TDF_STATS)) | |
56cf8686 | 4675 | { |
0ff4040e SP |
4676 | fprintf (dump_file, "Dependence tester statistics:\n"); |
4677 | ||
b8698a0f | 4678 | fprintf (dump_file, "Number of dependence tests: %d\n", |
0ff4040e | 4679 | dependence_stats.num_dependence_tests); |
b8698a0f | 4680 | fprintf (dump_file, "Number of dependence tests classified dependent: %d\n", |
0ff4040e | 4681 | dependence_stats.num_dependence_dependent); |
b8698a0f | 4682 | fprintf (dump_file, "Number of dependence tests classified independent: %d\n", |
0ff4040e | 4683 | dependence_stats.num_dependence_independent); |
b8698a0f | 4684 | fprintf (dump_file, "Number of undetermined dependence tests: %d\n", |
0ff4040e SP |
4685 | dependence_stats.num_dependence_undetermined); |
4686 | ||
b8698a0f | 4687 | fprintf (dump_file, "Number of subscript tests: %d\n", |
0ff4040e | 4688 | dependence_stats.num_subscript_tests); |
b8698a0f | 4689 | fprintf (dump_file, "Number of undetermined subscript tests: %d\n", |
0ff4040e | 4690 | dependence_stats.num_subscript_undetermined); |
b8698a0f | 4691 | fprintf (dump_file, "Number of same subscript function: %d\n", |
0ff4040e SP |
4692 | dependence_stats.num_same_subscript_function); |
4693 | ||
4694 | fprintf (dump_file, "Number of ziv tests: %d\n", | |
4695 | dependence_stats.num_ziv); | |
4696 | fprintf (dump_file, "Number of ziv tests returning dependent: %d\n", | |
4697 | dependence_stats.num_ziv_dependent); | |
4698 | fprintf (dump_file, "Number of ziv tests returning independent: %d\n", | |
4699 | dependence_stats.num_ziv_independent); | |
4700 | fprintf (dump_file, "Number of ziv tests unimplemented: %d\n", | |
b8698a0f | 4701 | dependence_stats.num_ziv_unimplemented); |
0ff4040e | 4702 | |
b8698a0f | 4703 | fprintf (dump_file, "Number of siv tests: %d\n", |
0ff4040e SP |
4704 | dependence_stats.num_siv); |
4705 | fprintf (dump_file, "Number of siv tests returning dependent: %d\n", | |
4706 | dependence_stats.num_siv_dependent); | |
4707 | fprintf (dump_file, "Number of siv tests returning independent: %d\n", | |
4708 | dependence_stats.num_siv_independent); | |
4709 | fprintf (dump_file, "Number of siv tests unimplemented: %d\n", | |
4710 | dependence_stats.num_siv_unimplemented); | |
4711 | ||
b8698a0f | 4712 | fprintf (dump_file, "Number of miv tests: %d\n", |
0ff4040e SP |
4713 | dependence_stats.num_miv); |
4714 | fprintf (dump_file, "Number of miv tests returning dependent: %d\n", | |
4715 | dependence_stats.num_miv_dependent); | |
4716 | fprintf (dump_file, "Number of miv tests returning independent: %d\n", | |
4717 | dependence_stats.num_miv_independent); | |
4718 | fprintf (dump_file, "Number of miv tests unimplemented: %d\n", | |
4719 | dependence_stats.num_miv_unimplemented); | |
9f275479 JS |
4720 | } |
4721 | ||
4722 | return res; | |
56cf8686 SP |
4723 | } |
4724 | ||
b8698a0f | 4725 | /* Returns true when the data dependences for the basic block BB have been |
a70d6342 | 4726 | computed, false otherwise. |
b8698a0f | 4727 | DATAREFS is initialized to all the array elements contained in this basic |
a70d6342 IR |
4728 | block, DEPENDENCE_RELATIONS contains the relations between the data |
4729 | references. Compute read-read and self relations if | |
4730 | COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ | |
4731 | bool | |
4732 | compute_data_dependences_for_bb (basic_block bb, | |
4733 | bool compute_self_and_read_read_dependences, | |
9771b263 DN |
4734 | vec<data_reference_p> *datarefs, |
4735 | vec<ddr_p> *dependence_relations) | |
a70d6342 IR |
4736 | { |
4737 | if (find_data_references_in_bb (NULL, bb, datarefs) == chrec_dont_know) | |
4738 | return false; | |
4739 | ||
6e1aa848 | 4740 | return compute_all_dependences (*datarefs, dependence_relations, vNULL, |
3881dee9 | 4741 | compute_self_and_read_read_dependences); |
a70d6342 IR |
4742 | } |
4743 | ||
56cf8686 | 4744 | /* Entry point (for testing only). Analyze all the data references |
3d8864c0 | 4745 | and the dependence relations in LOOP. |
56cf8686 | 4746 | |
b8698a0f L |
4747 | The data references are computed first. |
4748 | ||
56cf8686 SP |
4749 | A relation on these nodes is represented by a complete graph. Some |
4750 | of the relations could be of no interest, thus the relations can be | |
4751 | computed on demand. | |
b8698a0f | 4752 | |
56cf8686 SP |
4753 | In the following function we compute all the relations. This is |
4754 | just a first implementation that is here for: | |
b8698a0f | 4755 | - for showing how to ask for the dependence relations, |
56cf8686 SP |
4756 | - for the debugging the whole dependence graph, |
4757 | - for the dejagnu testcases and maintenance. | |
b8698a0f | 4758 | |
56cf8686 SP |
4759 | It is possible to ask only for a part of the graph, avoiding to |
4760 | compute the whole dependence graph. The computed dependences are | |
4761 | stored in a knowledge base (KB) such that later queries don't | |
4762 | recompute the same information. The implementation of this KB is | |
4763 | transparent to the optimizer, and thus the KB can be changed with a | |
4764 | more efficient implementation, or the KB could be disabled. */ | |
b8698a0f | 4765 | static void |
3d8864c0 | 4766 | analyze_all_data_dependences (struct loop *loop) |
56cf8686 SP |
4767 | { |
4768 | unsigned int i; | |
56cf8686 | 4769 | int nb_data_refs = 10; |
9771b263 DN |
4770 | vec<data_reference_p> datarefs; |
4771 | datarefs.create (nb_data_refs); | |
4772 | vec<ddr_p> dependence_relations; | |
4773 | dependence_relations.create (nb_data_refs * nb_data_refs); | |
4774 | vec<loop_p> loop_nest; | |
4775 | loop_nest.create (3); | |
56cf8686 SP |
4776 | |
4777 | /* Compute DDs on the whole function. */ | |
01be8516 | 4778 | compute_data_dependences_for_loop (loop, false, &loop_nest, &datarefs, |
3d8864c0 | 4779 | &dependence_relations); |
56cf8686 SP |
4780 | |
4781 | if (dump_file) | |
4782 | { | |
4783 | dump_data_dependence_relations (dump_file, dependence_relations); | |
4784 | fprintf (dump_file, "\n\n"); | |
56cf8686 | 4785 | |
86df10e3 SP |
4786 | if (dump_flags & TDF_DETAILS) |
4787 | dump_dist_dir_vectors (dump_file, dependence_relations); | |
56cf8686 | 4788 | |
86df10e3 | 4789 | if (dump_flags & TDF_STATS) |
56cf8686 | 4790 | { |
86df10e3 SP |
4791 | unsigned nb_top_relations = 0; |
4792 | unsigned nb_bot_relations = 0; | |
86df10e3 | 4793 | unsigned nb_chrec_relations = 0; |
ebf78a47 | 4794 | struct data_dependence_relation *ddr; |
86df10e3 | 4795 | |
9771b263 | 4796 | FOR_EACH_VEC_ELT (dependence_relations, i, ddr) |
86df10e3 | 4797 | { |
86df10e3 SP |
4798 | if (chrec_contains_undetermined (DDR_ARE_DEPENDENT (ddr))) |
4799 | nb_top_relations++; | |
b8698a0f | 4800 | |
86df10e3 | 4801 | else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) |
5006671f | 4802 | nb_bot_relations++; |
b8698a0f L |
4803 | |
4804 | else | |
86df10e3 SP |
4805 | nb_chrec_relations++; |
4806 | } | |
b8698a0f | 4807 | |
86df10e3 SP |
4808 | gather_stats_on_scev_database (); |
4809 | } | |
56cf8686 | 4810 | } |
36d59cf7 | 4811 | |
9771b263 | 4812 | loop_nest.release (); |
36d59cf7 DB |
4813 | free_dependence_relations (dependence_relations); |
4814 | free_data_refs (datarefs); | |
4815 | } | |
3d8864c0 SP |
4816 | |
4817 | /* Computes all the data dependences and check that the results of | |
4818 | several analyzers are the same. */ | |
4819 | ||
4820 | void | |
4821 | tree_check_data_deps (void) | |
4822 | { | |
3d8864c0 SP |
4823 | struct loop *loop_nest; |
4824 | ||
f0bd40b1 | 4825 | FOR_EACH_LOOP (loop_nest, 0) |
3d8864c0 SP |
4826 | analyze_all_data_dependences (loop_nest); |
4827 | } | |
36d59cf7 DB |
4828 | |
4829 | /* Free the memory used by a data dependence relation DDR. */ | |
4830 | ||
4831 | void | |
4832 | free_dependence_relation (struct data_dependence_relation *ddr) | |
4833 | { | |
4834 | if (ddr == NULL) | |
4835 | return; | |
4836 | ||
9771b263 | 4837 | if (DDR_SUBSCRIPTS (ddr).exists ()) |
d93817c4 | 4838 | free_subscripts (DDR_SUBSCRIPTS (ddr)); |
9771b263 DN |
4839 | DDR_DIST_VECTS (ddr).release (); |
4840 | DDR_DIR_VECTS (ddr).release (); | |
ebf78a47 | 4841 | |
36d59cf7 DB |
4842 | free (ddr); |
4843 | } | |
4844 | ||
4845 | /* Free the memory used by the data dependence relations from | |
4846 | DEPENDENCE_RELATIONS. */ | |
4847 | ||
b8698a0f | 4848 | void |
9771b263 | 4849 | free_dependence_relations (vec<ddr_p> dependence_relations) |
36d59cf7 DB |
4850 | { |
4851 | unsigned int i; | |
ebf78a47 | 4852 | struct data_dependence_relation *ddr; |
36d59cf7 | 4853 | |
9771b263 | 4854 | FOR_EACH_VEC_ELT (dependence_relations, i, ddr) |
01be8516 | 4855 | if (ddr) |
3ac57120 | 4856 | free_dependence_relation (ddr); |
ebf78a47 | 4857 | |
9771b263 | 4858 | dependence_relations.release (); |
56cf8686 SP |
4859 | } |
4860 | ||
36d59cf7 DB |
4861 | /* Free the memory used by the data references from DATAREFS. */ |
4862 | ||
4863 | void | |
9771b263 | 4864 | free_data_refs (vec<data_reference_p> datarefs) |
36d59cf7 DB |
4865 | { |
4866 | unsigned int i; | |
ebf78a47 | 4867 | struct data_reference *dr; |
56cf8686 | 4868 | |
9771b263 | 4869 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
8fdbc9c6 | 4870 | free_data_ref (dr); |
9771b263 | 4871 | datarefs.release (); |
36d59cf7 | 4872 | } |