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2abae5f1 | 1 | /* Detection of Static Control Parts (SCoP) for Graphite. |
c75c517d | 2 | Copyright (C) 2009, 2010 Free Software Foundation, Inc. |
2abae5f1 SP |
3 | Contributed by Sebastian Pop <sebastian.pop@amd.com> and |
4 | Tobias Grosser <grosser@fim.uni-passau.de>. | |
5 | ||
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 3, or (at your option) | |
11 | any later version. | |
12 | ||
13 | GCC is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GCC; see the file COPYING3. If not see | |
20 | <http://www.gnu.org/licenses/>. */ | |
21 | ||
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "coretypes.h" | |
2abae5f1 | 25 | #include "tree-flow.h" |
2abae5f1 SP |
26 | #include "cfgloop.h" |
27 | #include "tree-chrec.h" | |
28 | #include "tree-data-ref.h" | |
29 | #include "tree-scalar-evolution.h" | |
30 | #include "tree-pass.h" | |
2abae5f1 SP |
31 | #include "sese.h" |
32 | ||
33 | #ifdef HAVE_cloog | |
2abae5f1 SP |
34 | #include "ppl_c.h" |
35 | #include "graphite-ppl.h" | |
2abae5f1 SP |
36 | #include "graphite-poly.h" |
37 | #include "graphite-scop-detection.h" | |
38 | ||
39 | /* The type of the analyzed basic block. */ | |
40 | ||
41 | typedef enum gbb_type { | |
42 | GBB_UNKNOWN, | |
43 | GBB_LOOP_SING_EXIT_HEADER, | |
44 | GBB_LOOP_MULT_EXIT_HEADER, | |
45 | GBB_LOOP_EXIT, | |
46 | GBB_COND_HEADER, | |
47 | GBB_SIMPLE, | |
48 | GBB_LAST | |
49 | } gbb_type; | |
50 | ||
51 | /* Detect the type of BB. Loop headers are only marked, if they are | |
52 | new. This means their loop_father is different to LAST_LOOP. | |
53 | Otherwise they are treated like any other bb and their type can be | |
54 | any other type. */ | |
55 | ||
56 | static gbb_type | |
57 | get_bb_type (basic_block bb, struct loop *last_loop) | |
58 | { | |
59 | VEC (basic_block, heap) *dom; | |
60 | int nb_dom, nb_suc; | |
61 | struct loop *loop = bb->loop_father; | |
62 | ||
63 | /* Check, if we entry into a new loop. */ | |
64 | if (loop != last_loop) | |
65 | { | |
66 | if (single_exit (loop) != NULL) | |
67 | return GBB_LOOP_SING_EXIT_HEADER; | |
68 | else if (loop->num != 0) | |
69 | return GBB_LOOP_MULT_EXIT_HEADER; | |
70 | else | |
71 | return GBB_COND_HEADER; | |
72 | } | |
73 | ||
74 | dom = get_dominated_by (CDI_DOMINATORS, bb); | |
75 | nb_dom = VEC_length (basic_block, dom); | |
76 | VEC_free (basic_block, heap, dom); | |
77 | ||
78 | if (nb_dom == 0) | |
79 | return GBB_LAST; | |
80 | ||
81 | nb_suc = VEC_length (edge, bb->succs); | |
82 | ||
83 | if (nb_dom == 1 && nb_suc == 1) | |
84 | return GBB_SIMPLE; | |
85 | ||
86 | return GBB_COND_HEADER; | |
87 | } | |
88 | ||
89 | /* A SCoP detection region, defined using bbs as borders. | |
90 | ||
91 | All control flow touching this region, comes in passing basic_block | |
92 | ENTRY and leaves passing basic_block EXIT. By using bbs instead of | |
93 | edges for the borders we are able to represent also regions that do | |
94 | not have a single entry or exit edge. | |
95 | ||
96 | But as they have a single entry basic_block and a single exit | |
97 | basic_block, we are able to generate for every sd_region a single | |
98 | entry and exit edge. | |
99 | ||
100 | 1 2 | |
101 | \ / | |
102 | 3 <- entry | |
103 | | | |
104 | 4 | |
105 | / \ This region contains: {3, 4, 5, 6, 7, 8} | |
106 | 5 6 | |
107 | | | | |
108 | 7 8 | |
109 | \ / | |
110 | 9 <- exit */ | |
111 | ||
112 | ||
113 | typedef struct sd_region_p | |
114 | { | |
115 | /* The entry bb dominates all bbs in the sd_region. It is part of | |
116 | the region. */ | |
117 | basic_block entry; | |
118 | ||
119 | /* The exit bb postdominates all bbs in the sd_region, but is not | |
120 | part of the region. */ | |
121 | basic_block exit; | |
122 | } sd_region; | |
123 | ||
124 | DEF_VEC_O(sd_region); | |
125 | DEF_VEC_ALLOC_O(sd_region, heap); | |
126 | ||
127 | ||
128 | /* Moves the scops from SOURCE to TARGET and clean up SOURCE. */ | |
129 | ||
130 | static void | |
131 | move_sd_regions (VEC (sd_region, heap) **source, | |
132 | VEC (sd_region, heap) **target) | |
133 | { | |
134 | sd_region *s; | |
135 | int i; | |
136 | ||
ac47786e | 137 | FOR_EACH_VEC_ELT (sd_region, *source, i, s) |
2abae5f1 SP |
138 | VEC_safe_push (sd_region, heap, *target, s); |
139 | ||
140 | VEC_free (sd_region, heap, *source); | |
141 | } | |
142 | ||
143 | /* Something like "n * m" is not allowed. */ | |
144 | ||
145 | static bool | |
146 | graphite_can_represent_init (tree e) | |
147 | { | |
148 | switch (TREE_CODE (e)) | |
149 | { | |
150 | case POLYNOMIAL_CHREC: | |
151 | return graphite_can_represent_init (CHREC_LEFT (e)) | |
152 | && graphite_can_represent_init (CHREC_RIGHT (e)); | |
153 | ||
154 | case MULT_EXPR: | |
155 | if (chrec_contains_symbols (TREE_OPERAND (e, 0))) | |
d505015a SP |
156 | return graphite_can_represent_init (TREE_OPERAND (e, 0)) |
157 | && host_integerp (TREE_OPERAND (e, 1), 0); | |
2abae5f1 | 158 | else |
d505015a SP |
159 | return graphite_can_represent_init (TREE_OPERAND (e, 1)) |
160 | && host_integerp (TREE_OPERAND (e, 0), 0); | |
2abae5f1 SP |
161 | |
162 | case PLUS_EXPR: | |
163 | case POINTER_PLUS_EXPR: | |
164 | case MINUS_EXPR: | |
165 | return graphite_can_represent_init (TREE_OPERAND (e, 0)) | |
166 | && graphite_can_represent_init (TREE_OPERAND (e, 1)); | |
167 | ||
168 | case NEGATE_EXPR: | |
169 | case BIT_NOT_EXPR: | |
170 | CASE_CONVERT: | |
171 | case NON_LVALUE_EXPR: | |
172 | return graphite_can_represent_init (TREE_OPERAND (e, 0)); | |
173 | ||
174 | default: | |
175 | break; | |
176 | } | |
177 | ||
178 | return true; | |
179 | } | |
180 | ||
181 | /* Return true when SCEV can be represented in the polyhedral model. | |
182 | ||
183 | An expression can be represented, if it can be expressed as an | |
184 | affine expression. For loops (i, j) and parameters (m, n) all | |
185 | affine expressions are of the form: | |
186 | ||
187 | x1 * i + x2 * j + x3 * m + x4 * n + x5 * 1 where x1..x5 element of Z | |
188 | ||
189 | 1 i + 20 j + (-2) m + 25 | |
190 | ||
56f30f65 | 191 | Something like "i * n" or "n * m" is not allowed. */ |
2abae5f1 SP |
192 | |
193 | static bool | |
56f30f65 | 194 | graphite_can_represent_scev (tree scev) |
2abae5f1 SP |
195 | { |
196 | if (chrec_contains_undetermined (scev)) | |
197 | return false; | |
198 | ||
4b216ab0 SP |
199 | switch (TREE_CODE (scev)) |
200 | { | |
201 | case PLUS_EXPR: | |
202 | case MINUS_EXPR: | |
56f30f65 VK |
203 | return graphite_can_represent_scev (TREE_OPERAND (scev, 0)) |
204 | && graphite_can_represent_scev (TREE_OPERAND (scev, 1)); | |
2abae5f1 | 205 | |
4b216ab0 SP |
206 | case MULT_EXPR: |
207 | return !CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (scev, 0))) | |
208 | && !CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (scev, 1))) | |
209 | && !(chrec_contains_symbols (TREE_OPERAND (scev, 0)) | |
210 | && chrec_contains_symbols (TREE_OPERAND (scev, 1))) | |
c4c4983e | 211 | && graphite_can_represent_init (scev) |
56f30f65 VK |
212 | && graphite_can_represent_scev (TREE_OPERAND (scev, 0)) |
213 | && graphite_can_represent_scev (TREE_OPERAND (scev, 1)); | |
2abae5f1 | 214 | |
4b216ab0 SP |
215 | case POLYNOMIAL_CHREC: |
216 | /* Check for constant strides. With a non constant stride of | |
217 | 'n' we would have a value of 'iv * n'. Also check that the | |
218 | initial value can represented: for example 'n * m' cannot be | |
219 | represented. */ | |
220 | if (!evolution_function_right_is_integer_cst (scev) | |
221 | || !graphite_can_represent_init (scev)) | |
222 | return false; | |
223 | ||
224 | default: | |
225 | break; | |
226 | } | |
2abae5f1 SP |
227 | |
228 | /* Only affine functions can be represented. */ | |
229 | if (!scev_is_linear_expression (scev)) | |
230 | return false; | |
231 | ||
d9ae7906 | 232 | return true; |
2abae5f1 SP |
233 | } |
234 | ||
235 | ||
236 | /* Return true when EXPR can be represented in the polyhedral model. | |
237 | ||
238 | This means an expression can be represented, if it is linear with | |
239 | respect to the loops and the strides are non parametric. | |
56f30f65 | 240 | LOOP is the place where the expr will be evaluated. SCOP_ENTRY defines the |
2abae5f1 SP |
241 | entry of the region we analyse. */ |
242 | ||
243 | static bool | |
244 | graphite_can_represent_expr (basic_block scop_entry, loop_p loop, | |
56f30f65 | 245 | tree expr) |
2abae5f1 SP |
246 | { |
247 | tree scev = analyze_scalar_evolution (loop, expr); | |
248 | ||
249 | scev = instantiate_scev (scop_entry, loop, scev); | |
250 | ||
56f30f65 | 251 | return graphite_can_represent_scev (scev); |
2abae5f1 SP |
252 | } |
253 | ||
2abae5f1 SP |
254 | /* Return true if the data references of STMT can be represented by |
255 | Graphite. */ | |
256 | ||
257 | static bool | |
258 | stmt_has_simple_data_refs_p (loop_p outermost_loop, gimple stmt) | |
259 | { | |
260 | data_reference_p dr; | |
261 | unsigned i; | |
262 | int j; | |
263 | bool res = true; | |
2abae5f1 SP |
264 | VEC (data_reference_p, heap) *drs = VEC_alloc (data_reference_p, heap, 5); |
265 | ||
5c640e29 SP |
266 | graphite_find_data_references_in_stmt (outermost_loop, |
267 | loop_containing_stmt (stmt), | |
268 | stmt, &drs); | |
2abae5f1 | 269 | |
ac47786e | 270 | FOR_EACH_VEC_ELT (data_reference_p, drs, j, dr) |
2abae5f1 | 271 | for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) |
56f30f65 | 272 | if (!graphite_can_represent_scev (DR_ACCESS_FN (dr, i))) |
2abae5f1 SP |
273 | { |
274 | res = false; | |
275 | goto done; | |
276 | } | |
277 | ||
278 | done: | |
279 | free_data_refs (drs); | |
280 | return res; | |
281 | } | |
282 | ||
2abae5f1 SP |
283 | /* Return true only when STMT is simple enough for being handled by |
284 | Graphite. This depends on SCOP_ENTRY, as the parameters are | |
285 | initialized relatively to this basic block, the linear functions | |
286 | are initialized to OUTERMOST_LOOP and BB is the place where we try | |
287 | to evaluate the STMT. */ | |
288 | ||
289 | static bool | |
290 | stmt_simple_for_scop_p (basic_block scop_entry, loop_p outermost_loop, | |
291 | gimple stmt, basic_block bb) | |
292 | { | |
293 | loop_p loop = bb->loop_father; | |
294 | ||
295 | gcc_assert (scop_entry); | |
296 | ||
297 | /* GIMPLE_ASM and GIMPLE_CALL may embed arbitrary side effects. | |
298 | Calls have side-effects, except those to const or pure | |
299 | functions. */ | |
300 | if (gimple_has_volatile_ops (stmt) | |
301 | || (gimple_code (stmt) == GIMPLE_CALL | |
302 | && !(gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE))) | |
303 | || (gimple_code (stmt) == GIMPLE_ASM)) | |
304 | return false; | |
305 | ||
a3201927 AO |
306 | if (is_gimple_debug (stmt)) |
307 | return true; | |
308 | ||
2abae5f1 SP |
309 | if (!stmt_has_simple_data_refs_p (outermost_loop, stmt)) |
310 | return false; | |
311 | ||
312 | switch (gimple_code (stmt)) | |
313 | { | |
314 | case GIMPLE_RETURN: | |
315 | case GIMPLE_LABEL: | |
316 | return true; | |
317 | ||
318 | case GIMPLE_COND: | |
319 | { | |
320 | tree op; | |
321 | ssa_op_iter op_iter; | |
322 | enum tree_code code = gimple_cond_code (stmt); | |
323 | ||
324 | /* We can handle all binary comparisons. Inequalities are | |
325 | also supported as they can be represented with union of | |
326 | polyhedra. */ | |
327 | if (!(code == LT_EXPR | |
328 | || code == GT_EXPR | |
329 | || code == LE_EXPR | |
330 | || code == GE_EXPR | |
331 | || code == EQ_EXPR | |
332 | || code == NE_EXPR)) | |
333 | return false; | |
334 | ||
335 | FOR_EACH_SSA_TREE_OPERAND (op, stmt, op_iter, SSA_OP_ALL_USES) | |
56f30f65 | 336 | if (!graphite_can_represent_expr (scop_entry, loop, op) |
2abae5f1 SP |
337 | /* We can not handle REAL_TYPE. Failed for pr39260. */ |
338 | || TREE_CODE (TREE_TYPE (op)) == REAL_TYPE) | |
339 | return false; | |
340 | ||
341 | return true; | |
342 | } | |
343 | ||
344 | case GIMPLE_ASSIGN: | |
2abae5f1 | 345 | case GIMPLE_CALL: |
c8ae0613 | 346 | return true; |
2abae5f1 SP |
347 | |
348 | default: | |
349 | /* These nodes cut a new scope. */ | |
350 | return false; | |
351 | } | |
352 | ||
353 | return false; | |
354 | } | |
355 | ||
356 | /* Returns the statement of BB that contains a harmful operation: that | |
357 | can be a function call with side effects, the induction variables | |
358 | are not linear with respect to SCOP_ENTRY, etc. The current open | |
359 | scop should end before this statement. The evaluation is limited using | |
360 | OUTERMOST_LOOP as outermost loop that may change. */ | |
361 | ||
362 | static gimple | |
363 | harmful_stmt_in_bb (basic_block scop_entry, loop_p outer_loop, basic_block bb) | |
364 | { | |
365 | gimple_stmt_iterator gsi; | |
366 | ||
367 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
368 | if (!stmt_simple_for_scop_p (scop_entry, outer_loop, gsi_stmt (gsi), bb)) | |
369 | return gsi_stmt (gsi); | |
370 | ||
371 | return NULL; | |
372 | } | |
373 | ||
45fc26fc VK |
374 | /* Return true if LOOP can be represented in the polyhedral |
375 | representation. This is evaluated taking SCOP_ENTRY and | |
376 | OUTERMOST_LOOP in mind. */ | |
2abae5f1 SP |
377 | |
378 | static bool | |
56f30f65 | 379 | graphite_can_represent_loop (basic_block scop_entry, loop_p loop) |
2abae5f1 | 380 | { |
cbc1994b SP |
381 | tree niter; |
382 | struct tree_niter_desc niter_desc; | |
2abae5f1 | 383 | |
cbc1994b SP |
384 | /* FIXME: For the moment, graphite cannot be used on loops that |
385 | iterate using induction variables that wrap. */ | |
2abae5f1 | 386 | |
cbc1994b SP |
387 | return number_of_iterations_exit (loop, single_exit (loop), &niter_desc, false) |
388 | && niter_desc.control.no_overflow | |
389 | && (niter = number_of_latch_executions (loop)) | |
390 | && !chrec_contains_undetermined (niter) | |
391 | && graphite_can_represent_expr (scop_entry, loop, niter); | |
2abae5f1 SP |
392 | } |
393 | ||
394 | /* Store information needed by scopdet_* functions. */ | |
395 | ||
396 | struct scopdet_info | |
397 | { | |
398 | /* Exit of the open scop would stop if the current BB is harmful. */ | |
399 | basic_block exit; | |
400 | ||
401 | /* Where the next scop would start if the current BB is harmful. */ | |
402 | basic_block next; | |
403 | ||
404 | /* The bb or one of its children contains open loop exits. That means | |
405 | loop exit nodes that are not surrounded by a loop dominated by bb. */ | |
406 | bool exits; | |
407 | ||
408 | /* The bb or one of its children contains only structures we can handle. */ | |
409 | bool difficult; | |
410 | }; | |
411 | ||
412 | static struct scopdet_info build_scops_1 (basic_block, loop_p, | |
413 | VEC (sd_region, heap) **, loop_p); | |
414 | ||
415 | /* Calculates BB infos. If bb is difficult we add valid SCoPs dominated by BB | |
416 | to SCOPS. TYPE is the gbb_type of BB. */ | |
417 | ||
418 | static struct scopdet_info | |
419 | scopdet_basic_block_info (basic_block bb, loop_p outermost_loop, | |
420 | VEC (sd_region, heap) **scops, gbb_type type) | |
421 | { | |
422 | loop_p loop = bb->loop_father; | |
423 | struct scopdet_info result; | |
424 | gimple stmt; | |
425 | ||
426 | /* XXX: ENTRY_BLOCK_PTR could be optimized in later steps. */ | |
427 | basic_block entry_block = ENTRY_BLOCK_PTR; | |
428 | stmt = harmful_stmt_in_bb (entry_block, outermost_loop, bb); | |
429 | result.difficult = (stmt != NULL); | |
430 | result.exit = NULL; | |
431 | ||
432 | switch (type) | |
433 | { | |
434 | case GBB_LAST: | |
435 | result.next = NULL; | |
436 | result.exits = false; | |
437 | ||
438 | /* Mark bbs terminating a SESE region difficult, if they start | |
439 | a condition. */ | |
440 | if (!single_succ_p (bb)) | |
441 | result.difficult = true; | |
442 | else | |
443 | result.exit = single_succ (bb); | |
444 | ||
445 | break; | |
446 | ||
447 | case GBB_SIMPLE: | |
448 | result.next = single_succ (bb); | |
449 | result.exits = false; | |
450 | result.exit = single_succ (bb); | |
451 | break; | |
452 | ||
453 | case GBB_LOOP_SING_EXIT_HEADER: | |
454 | { | |
455 | VEC (sd_region, heap) *regions = VEC_alloc (sd_region, heap, 3); | |
456 | struct scopdet_info sinfo; | |
457 | edge exit_e = single_exit (loop); | |
458 | ||
459 | sinfo = build_scops_1 (bb, outermost_loop, ®ions, loop); | |
460 | ||
56f30f65 | 461 | if (!graphite_can_represent_loop (entry_block, loop)) |
2abae5f1 SP |
462 | result.difficult = true; |
463 | ||
464 | result.difficult |= sinfo.difficult; | |
465 | ||
466 | /* Try again with another loop level. */ | |
467 | if (result.difficult | |
468 | && loop_depth (outermost_loop) + 1 == loop_depth (loop)) | |
469 | { | |
470 | outermost_loop = loop; | |
471 | ||
472 | VEC_free (sd_region, heap, regions); | |
473 | regions = VEC_alloc (sd_region, heap, 3); | |
474 | ||
475 | sinfo = scopdet_basic_block_info (bb, outermost_loop, scops, type); | |
476 | ||
477 | result = sinfo; | |
478 | result.difficult = true; | |
479 | ||
480 | if (sinfo.difficult) | |
481 | move_sd_regions (®ions, scops); | |
482 | else | |
483 | { | |
484 | sd_region open_scop; | |
485 | open_scop.entry = bb; | |
486 | open_scop.exit = exit_e->dest; | |
487 | VEC_safe_push (sd_region, heap, *scops, &open_scop); | |
488 | VEC_free (sd_region, heap, regions); | |
489 | } | |
490 | } | |
491 | else | |
492 | { | |
493 | result.exit = exit_e->dest; | |
494 | result.next = exit_e->dest; | |
495 | ||
496 | /* If we do not dominate result.next, remove it. It's either | |
497 | the EXIT_BLOCK_PTR, or another bb dominates it and will | |
498 | call the scop detection for this bb. */ | |
499 | if (!dominated_by_p (CDI_DOMINATORS, result.next, bb)) | |
500 | result.next = NULL; | |
501 | ||
502 | if (exit_e->src->loop_father != loop) | |
503 | result.next = NULL; | |
504 | ||
505 | result.exits = false; | |
506 | ||
507 | if (result.difficult) | |
508 | move_sd_regions (®ions, scops); | |
509 | else | |
510 | VEC_free (sd_region, heap, regions); | |
511 | } | |
512 | ||
513 | break; | |
514 | } | |
515 | ||
516 | case GBB_LOOP_MULT_EXIT_HEADER: | |
517 | { | |
518 | /* XXX: For now we just do not join loops with multiple exits. If the | |
519 | exits lead to the same bb it may be possible to join the loop. */ | |
520 | VEC (sd_region, heap) *regions = VEC_alloc (sd_region, heap, 3); | |
521 | VEC (edge, heap) *exits = get_loop_exit_edges (loop); | |
522 | edge e; | |
523 | int i; | |
524 | build_scops_1 (bb, loop, ®ions, loop); | |
525 | ||
526 | /* Scan the code dominated by this loop. This means all bbs, that are | |
527 | are dominated by a bb in this loop, but are not part of this loop. | |
528 | ||
529 | The easiest case: | |
530 | - The loop exit destination is dominated by the exit sources. | |
531 | ||
532 | TODO: We miss here the more complex cases: | |
533 | - The exit destinations are dominated by another bb inside | |
534 | the loop. | |
535 | - The loop dominates bbs, that are not exit destinations. */ | |
ac47786e | 536 | FOR_EACH_VEC_ELT (edge, exits, i, e) |
2abae5f1 SP |
537 | if (e->src->loop_father == loop |
538 | && dominated_by_p (CDI_DOMINATORS, e->dest, e->src)) | |
539 | { | |
540 | if (loop_outer (outermost_loop)) | |
541 | outermost_loop = loop_outer (outermost_loop); | |
542 | ||
543 | /* Pass loop_outer to recognize e->dest as loop header in | |
544 | build_scops_1. */ | |
545 | if (e->dest->loop_father->header == e->dest) | |
546 | build_scops_1 (e->dest, outermost_loop, ®ions, | |
547 | loop_outer (e->dest->loop_father)); | |
548 | else | |
549 | build_scops_1 (e->dest, outermost_loop, ®ions, | |
550 | e->dest->loop_father); | |
551 | } | |
552 | ||
553 | result.next = NULL; | |
554 | result.exit = NULL; | |
555 | result.difficult = true; | |
556 | result.exits = false; | |
557 | move_sd_regions (®ions, scops); | |
558 | VEC_free (edge, heap, exits); | |
559 | break; | |
560 | } | |
561 | case GBB_COND_HEADER: | |
562 | { | |
563 | VEC (sd_region, heap) *regions = VEC_alloc (sd_region, heap, 3); | |
564 | struct scopdet_info sinfo; | |
565 | VEC (basic_block, heap) *dominated; | |
566 | int i; | |
567 | basic_block dom_bb; | |
568 | basic_block last_exit = NULL; | |
569 | edge e; | |
570 | result.exits = false; | |
571 | ||
572 | /* First check the successors of BB, and check if it is | |
573 | possible to join the different branches. */ | |
ac47786e | 574 | FOR_EACH_VEC_ELT (edge, bb->succs, i, e) |
2abae5f1 SP |
575 | { |
576 | /* Ignore loop exits. They will be handled after the loop | |
577 | body. */ | |
f4ce375d | 578 | if (loop_exits_to_bb_p (loop, e->dest)) |
2abae5f1 SP |
579 | { |
580 | result.exits = true; | |
581 | continue; | |
582 | } | |
583 | ||
584 | /* Do not follow edges that lead to the end of the | |
585 | conditions block. For example, in | |
586 | ||
587 | | 0 | |
588 | | /|\ | |
589 | | 1 2 | | |
590 | | | | | | |
591 | | 3 4 | | |
592 | | \|/ | |
593 | | 6 | |
594 | ||
595 | the edge from 0 => 6. Only check if all paths lead to | |
596 | the same node 6. */ | |
597 | ||
598 | if (!single_pred_p (e->dest)) | |
599 | { | |
600 | /* Check, if edge leads directly to the end of this | |
601 | condition. */ | |
602 | if (!last_exit) | |
603 | last_exit = e->dest; | |
604 | ||
605 | if (e->dest != last_exit) | |
606 | result.difficult = true; | |
607 | ||
608 | continue; | |
609 | } | |
610 | ||
611 | if (!dominated_by_p (CDI_DOMINATORS, e->dest, bb)) | |
612 | { | |
613 | result.difficult = true; | |
614 | continue; | |
615 | } | |
616 | ||
617 | sinfo = build_scops_1 (e->dest, outermost_loop, ®ions, loop); | |
618 | ||
619 | result.exits |= sinfo.exits; | |
620 | result.difficult |= sinfo.difficult; | |
621 | ||
622 | /* Checks, if all branches end at the same point. | |
623 | If that is true, the condition stays joinable. | |
624 | Have a look at the example above. */ | |
625 | if (sinfo.exit) | |
626 | { | |
627 | if (!last_exit) | |
628 | last_exit = sinfo.exit; | |
629 | ||
630 | if (sinfo.exit != last_exit) | |
631 | result.difficult = true; | |
632 | } | |
633 | else | |
634 | result.difficult = true; | |
635 | } | |
636 | ||
637 | if (!last_exit) | |
638 | result.difficult = true; | |
639 | ||
640 | /* Join the branches of the condition if possible. */ | |
641 | if (!result.exits && !result.difficult) | |
642 | { | |
643 | /* Only return a next pointer if we dominate this pointer. | |
644 | Otherwise it will be handled by the bb dominating it. */ | |
645 | if (dominated_by_p (CDI_DOMINATORS, last_exit, bb) | |
646 | && last_exit != bb) | |
647 | result.next = last_exit; | |
648 | else | |
649 | result.next = NULL; | |
650 | ||
651 | result.exit = last_exit; | |
652 | ||
653 | VEC_free (sd_region, heap, regions); | |
654 | break; | |
655 | } | |
656 | ||
657 | /* Scan remaining bbs dominated by BB. */ | |
658 | dominated = get_dominated_by (CDI_DOMINATORS, bb); | |
659 | ||
ac47786e | 660 | FOR_EACH_VEC_ELT (basic_block, dominated, i, dom_bb) |
2abae5f1 SP |
661 | { |
662 | /* Ignore loop exits: they will be handled after the loop body. */ | |
663 | if (loop_depth (find_common_loop (loop, dom_bb->loop_father)) | |
664 | < loop_depth (loop)) | |
665 | { | |
666 | result.exits = true; | |
667 | continue; | |
668 | } | |
669 | ||
670 | /* Ignore the bbs processed above. */ | |
671 | if (single_pred_p (dom_bb) && single_pred (dom_bb) == bb) | |
672 | continue; | |
673 | ||
674 | if (loop_depth (loop) > loop_depth (dom_bb->loop_father)) | |
675 | sinfo = build_scops_1 (dom_bb, outermost_loop, ®ions, | |
676 | loop_outer (loop)); | |
677 | else | |
678 | sinfo = build_scops_1 (dom_bb, outermost_loop, ®ions, loop); | |
679 | ||
680 | result.exits |= sinfo.exits; | |
681 | result.difficult = true; | |
682 | result.exit = NULL; | |
683 | } | |
684 | ||
685 | VEC_free (basic_block, heap, dominated); | |
686 | ||
687 | result.next = NULL; | |
688 | move_sd_regions (®ions, scops); | |
689 | ||
690 | break; | |
691 | } | |
692 | ||
693 | default: | |
694 | gcc_unreachable (); | |
695 | } | |
696 | ||
697 | return result; | |
698 | } | |
699 | ||
700 | /* Starting from CURRENT we walk the dominance tree and add new sd_regions to | |
701 | SCOPS. The analyse if a sd_region can be handled is based on the value | |
702 | of OUTERMOST_LOOP. Only loops inside OUTERMOST loops may change. LOOP | |
703 | is the loop in which CURRENT is handled. | |
704 | ||
705 | TODO: These functions got a little bit big. They definitely should be cleaned | |
706 | up. */ | |
707 | ||
708 | static struct scopdet_info | |
709 | build_scops_1 (basic_block current, loop_p outermost_loop, | |
710 | VEC (sd_region, heap) **scops, loop_p loop) | |
711 | { | |
712 | bool in_scop = false; | |
713 | sd_region open_scop; | |
714 | struct scopdet_info sinfo; | |
715 | ||
716 | /* Initialize result. */ | |
717 | struct scopdet_info result; | |
718 | result.exits = false; | |
719 | result.difficult = false; | |
720 | result.next = NULL; | |
721 | result.exit = NULL; | |
722 | open_scop.entry = NULL; | |
723 | open_scop.exit = NULL; | |
724 | sinfo.exit = NULL; | |
725 | ||
726 | /* Loop over the dominance tree. If we meet a difficult bb, close | |
727 | the current SCoP. Loop and condition header start a new layer, | |
728 | and can only be added if all bbs in deeper layers are simple. */ | |
729 | while (current != NULL) | |
730 | { | |
731 | sinfo = scopdet_basic_block_info (current, outermost_loop, scops, | |
732 | get_bb_type (current, loop)); | |
733 | ||
734 | if (!in_scop && !(sinfo.exits || sinfo.difficult)) | |
735 | { | |
736 | open_scop.entry = current; | |
737 | open_scop.exit = NULL; | |
738 | in_scop = true; | |
739 | } | |
740 | else if (in_scop && (sinfo.exits || sinfo.difficult)) | |
741 | { | |
742 | open_scop.exit = current; | |
743 | VEC_safe_push (sd_region, heap, *scops, &open_scop); | |
744 | in_scop = false; | |
745 | } | |
746 | ||
747 | result.difficult |= sinfo.difficult; | |
748 | result.exits |= sinfo.exits; | |
749 | ||
750 | current = sinfo.next; | |
751 | } | |
752 | ||
753 | /* Try to close open_scop, if we are still in an open SCoP. */ | |
754 | if (in_scop) | |
755 | { | |
756 | open_scop.exit = sinfo.exit; | |
757 | gcc_assert (open_scop.exit); | |
758 | VEC_safe_push (sd_region, heap, *scops, &open_scop); | |
759 | } | |
760 | ||
761 | result.exit = sinfo.exit; | |
762 | return result; | |
763 | } | |
764 | ||
765 | /* Checks if a bb is contained in REGION. */ | |
766 | ||
767 | static bool | |
768 | bb_in_sd_region (basic_block bb, sd_region *region) | |
769 | { | |
770 | return bb_in_region (bb, region->entry, region->exit); | |
771 | } | |
772 | ||
773 | /* Returns the single entry edge of REGION, if it does not exits NULL. */ | |
774 | ||
775 | static edge | |
776 | find_single_entry_edge (sd_region *region) | |
777 | { | |
778 | edge e; | |
779 | edge_iterator ei; | |
780 | edge entry = NULL; | |
781 | ||
782 | FOR_EACH_EDGE (e, ei, region->entry->preds) | |
783 | if (!bb_in_sd_region (e->src, region)) | |
784 | { | |
785 | if (entry) | |
786 | { | |
787 | entry = NULL; | |
788 | break; | |
789 | } | |
790 | ||
791 | else | |
792 | entry = e; | |
793 | } | |
794 | ||
795 | return entry; | |
796 | } | |
797 | ||
798 | /* Returns the single exit edge of REGION, if it does not exits NULL. */ | |
799 | ||
800 | static edge | |
801 | find_single_exit_edge (sd_region *region) | |
802 | { | |
803 | edge e; | |
804 | edge_iterator ei; | |
805 | edge exit = NULL; | |
806 | ||
807 | FOR_EACH_EDGE (e, ei, region->exit->preds) | |
808 | if (bb_in_sd_region (e->src, region)) | |
809 | { | |
810 | if (exit) | |
811 | { | |
812 | exit = NULL; | |
813 | break; | |
814 | } | |
815 | ||
816 | else | |
817 | exit = e; | |
818 | } | |
819 | ||
820 | return exit; | |
821 | } | |
822 | ||
823 | /* Create a single entry edge for REGION. */ | |
824 | ||
825 | static void | |
826 | create_single_entry_edge (sd_region *region) | |
827 | { | |
828 | if (find_single_entry_edge (region)) | |
829 | return; | |
830 | ||
831 | /* There are multiple predecessors for bb_3 | |
832 | ||
833 | | 1 2 | |
834 | | | / | |
835 | | |/ | |
836 | | 3 <- entry | |
837 | | |\ | |
838 | | | | | |
839 | | 4 ^ | |
840 | | | | | |
841 | | |/ | |
842 | | 5 | |
843 | ||
844 | There are two edges (1->3, 2->3), that point from outside into the region, | |
845 | and another one (5->3), a loop latch, lead to bb_3. | |
846 | ||
847 | We split bb_3. | |
848 | ||
849 | | 1 2 | |
850 | | | / | |
851 | | |/ | |
852 | |3.0 | |
853 | | |\ (3.0 -> 3.1) = single entry edge | |
854 | |3.1 | <- entry | |
855 | | | | | |
856 | | | | | |
857 | | 4 ^ | |
858 | | | | | |
859 | | |/ | |
860 | | 5 | |
861 | ||
862 | If the loop is part of the SCoP, we have to redirect the loop latches. | |
863 | ||
864 | | 1 2 | |
865 | | | / | |
866 | | |/ | |
867 | |3.0 | |
868 | | | (3.0 -> 3.1) = entry edge | |
869 | |3.1 <- entry | |
870 | | |\ | |
871 | | | | | |
872 | | 4 ^ | |
873 | | | | | |
874 | | |/ | |
875 | | 5 */ | |
876 | ||
877 | if (region->entry->loop_father->header != region->entry | |
878 | || dominated_by_p (CDI_DOMINATORS, | |
879 | loop_latch_edge (region->entry->loop_father)->src, | |
880 | region->exit)) | |
881 | { | |
882 | edge forwarder = split_block_after_labels (region->entry); | |
883 | region->entry = forwarder->dest; | |
884 | } | |
885 | else | |
886 | /* This case is never executed, as the loop headers seem always to have a | |
887 | single edge pointing from outside into the loop. */ | |
888 | gcc_unreachable (); | |
889 | ||
77a74ed7 | 890 | gcc_checking_assert (find_single_entry_edge (region)); |
2abae5f1 SP |
891 | } |
892 | ||
893 | /* Check if the sd_region, mentioned in EDGE, has no exit bb. */ | |
894 | ||
895 | static bool | |
896 | sd_region_without_exit (edge e) | |
897 | { | |
898 | sd_region *r = (sd_region *) e->aux; | |
899 | ||
900 | if (r) | |
901 | return r->exit == NULL; | |
902 | else | |
903 | return false; | |
904 | } | |
905 | ||
906 | /* Create a single exit edge for REGION. */ | |
907 | ||
908 | static void | |
909 | create_single_exit_edge (sd_region *region) | |
910 | { | |
911 | edge e; | |
912 | edge_iterator ei; | |
913 | edge forwarder = NULL; | |
914 | basic_block exit; | |
915 | ||
2abae5f1 SP |
916 | /* We create a forwarder bb (5) for all edges leaving this region |
917 | (3->5, 4->5). All other edges leading to the same bb, are moved | |
918 | to a new bb (6). If these edges where part of another region (2->5) | |
919 | we update the region->exit pointer, of this region. | |
920 | ||
921 | To identify which edge belongs to which region we depend on the e->aux | |
922 | pointer in every edge. It points to the region of the edge or to NULL, | |
923 | if the edge is not part of any region. | |
924 | ||
925 | 1 2 3 4 1->5 no region, 2->5 region->exit = 5, | |
926 | \| |/ 3->5 region->exit = NULL, 4->5 region->exit = NULL | |
927 | 5 <- exit | |
928 | ||
929 | changes to | |
930 | ||
931 | 1 2 3 4 1->6 no region, 2->6 region->exit = 6, | |
932 | | | \/ 3->5 no region, 4->5 no region, | |
933 | | | 5 | |
934 | \| / 5->6 region->exit = 6 | |
935 | 6 | |
936 | ||
937 | Now there is only a single exit edge (5->6). */ | |
938 | exit = region->exit; | |
939 | region->exit = NULL; | |
940 | forwarder = make_forwarder_block (exit, &sd_region_without_exit, NULL); | |
941 | ||
942 | /* Unmark the edges, that are no longer exit edges. */ | |
943 | FOR_EACH_EDGE (e, ei, forwarder->src->preds) | |
944 | if (e->aux) | |
945 | e->aux = NULL; | |
946 | ||
947 | /* Mark the new exit edge. */ | |
948 | single_succ_edge (forwarder->src)->aux = region; | |
949 | ||
950 | /* Update the exit bb of all regions, where exit edges lead to | |
951 | forwarder->dest. */ | |
952 | FOR_EACH_EDGE (e, ei, forwarder->dest->preds) | |
953 | if (e->aux) | |
954 | ((sd_region *) e->aux)->exit = forwarder->dest; | |
955 | ||
77a74ed7 | 956 | gcc_checking_assert (find_single_exit_edge (region)); |
2abae5f1 SP |
957 | } |
958 | ||
959 | /* Unmark the exit edges of all REGIONS. | |
960 | See comment in "create_single_exit_edge". */ | |
961 | ||
962 | static void | |
963 | unmark_exit_edges (VEC (sd_region, heap) *regions) | |
964 | { | |
965 | int i; | |
966 | sd_region *s; | |
967 | edge e; | |
968 | edge_iterator ei; | |
969 | ||
ac47786e | 970 | FOR_EACH_VEC_ELT (sd_region, regions, i, s) |
2abae5f1 SP |
971 | FOR_EACH_EDGE (e, ei, s->exit->preds) |
972 | e->aux = NULL; | |
973 | } | |
974 | ||
975 | ||
976 | /* Mark the exit edges of all REGIONS. | |
977 | See comment in "create_single_exit_edge". */ | |
978 | ||
979 | static void | |
980 | mark_exit_edges (VEC (sd_region, heap) *regions) | |
981 | { | |
982 | int i; | |
983 | sd_region *s; | |
984 | edge e; | |
985 | edge_iterator ei; | |
986 | ||
ac47786e | 987 | FOR_EACH_VEC_ELT (sd_region, regions, i, s) |
2abae5f1 SP |
988 | FOR_EACH_EDGE (e, ei, s->exit->preds) |
989 | if (bb_in_sd_region (e->src, s)) | |
990 | e->aux = s; | |
991 | } | |
992 | ||
993 | /* Create for all scop regions a single entry and a single exit edge. */ | |
994 | ||
995 | static void | |
996 | create_sese_edges (VEC (sd_region, heap) *regions) | |
997 | { | |
998 | int i; | |
999 | sd_region *s; | |
1000 | ||
ac47786e | 1001 | FOR_EACH_VEC_ELT (sd_region, regions, i, s) |
2abae5f1 SP |
1002 | create_single_entry_edge (s); |
1003 | ||
1004 | mark_exit_edges (regions); | |
1005 | ||
ac47786e | 1006 | FOR_EACH_VEC_ELT (sd_region, regions, i, s) |
4caa8e21 SP |
1007 | /* Don't handle multiple edges exiting the function. */ |
1008 | if (!find_single_exit_edge (s) | |
1009 | && s->exit != EXIT_BLOCK_PTR) | |
1010 | create_single_exit_edge (s); | |
2abae5f1 SP |
1011 | |
1012 | unmark_exit_edges (regions); | |
1013 | ||
1014 | fix_loop_structure (NULL); | |
1015 | ||
1016 | #ifdef ENABLE_CHECKING | |
1017 | verify_loop_structure (); | |
1018 | verify_dominators (CDI_DOMINATORS); | |
1019 | verify_ssa (false); | |
1020 | #endif | |
1021 | } | |
1022 | ||
1023 | /* Create graphite SCoPs from an array of scop detection REGIONS. */ | |
1024 | ||
1025 | static void | |
1026 | build_graphite_scops (VEC (sd_region, heap) *regions, | |
1027 | VEC (scop_p, heap) **scops) | |
1028 | { | |
1029 | int i; | |
1030 | sd_region *s; | |
1031 | ||
ac47786e | 1032 | FOR_EACH_VEC_ELT (sd_region, regions, i, s) |
2abae5f1 SP |
1033 | { |
1034 | edge entry = find_single_entry_edge (s); | |
1035 | edge exit = find_single_exit_edge (s); | |
4caa8e21 SP |
1036 | scop_p scop; |
1037 | ||
1038 | if (!exit) | |
1039 | continue; | |
1040 | ||
1041 | scop = new_scop (new_sese (entry, exit)); | |
2abae5f1 SP |
1042 | VEC_safe_push (scop_p, heap, *scops, scop); |
1043 | ||
1044 | /* Are there overlapping SCoPs? */ | |
1045 | #ifdef ENABLE_CHECKING | |
1046 | { | |
1047 | int j; | |
1048 | sd_region *s2; | |
1049 | ||
ac47786e | 1050 | FOR_EACH_VEC_ELT (sd_region, regions, j, s2) |
2abae5f1 SP |
1051 | if (s != s2) |
1052 | gcc_assert (!bb_in_sd_region (s->entry, s2)); | |
1053 | } | |
1054 | #endif | |
1055 | } | |
1056 | } | |
1057 | ||
1058 | /* Returns true when BB contains only close phi nodes. */ | |
1059 | ||
1060 | static bool | |
1061 | contains_only_close_phi_nodes (basic_block bb) | |
1062 | { | |
1063 | gimple_stmt_iterator gsi; | |
1064 | ||
1065 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1066 | if (gimple_code (gsi_stmt (gsi)) != GIMPLE_LABEL) | |
1067 | return false; | |
1068 | ||
1069 | return true; | |
1070 | } | |
1071 | ||
1072 | /* Print statistics for SCOP to FILE. */ | |
1073 | ||
1074 | static void | |
1075 | print_graphite_scop_statistics (FILE* file, scop_p scop) | |
1076 | { | |
1077 | long n_bbs = 0; | |
1078 | long n_loops = 0; | |
1079 | long n_stmts = 0; | |
1080 | long n_conditions = 0; | |
1081 | long n_p_bbs = 0; | |
1082 | long n_p_loops = 0; | |
1083 | long n_p_stmts = 0; | |
1084 | long n_p_conditions = 0; | |
1085 | ||
1086 | basic_block bb; | |
1087 | ||
1088 | FOR_ALL_BB (bb) | |
1089 | { | |
1090 | gimple_stmt_iterator psi; | |
1091 | loop_p loop = bb->loop_father; | |
1092 | ||
1093 | if (!bb_in_sese_p (bb, SCOP_REGION (scop))) | |
1094 | continue; | |
1095 | ||
1096 | n_bbs++; | |
1097 | n_p_bbs += bb->count; | |
1098 | ||
1099 | if (VEC_length (edge, bb->succs) > 1) | |
1100 | { | |
1101 | n_conditions++; | |
1102 | n_p_conditions += bb->count; | |
1103 | } | |
1104 | ||
1105 | for (psi = gsi_start_bb (bb); !gsi_end_p (psi); gsi_next (&psi)) | |
1106 | { | |
1107 | n_stmts++; | |
1108 | n_p_stmts += bb->count; | |
1109 | } | |
1110 | ||
1111 | if (loop->header == bb && loop_in_sese_p (loop, SCOP_REGION (scop))) | |
1112 | { | |
1113 | n_loops++; | |
1114 | n_p_loops += bb->count; | |
1115 | } | |
1116 | ||
1117 | } | |
1118 | ||
1119 | fprintf (file, "\nBefore limit_scops SCoP statistics ("); | |
1120 | fprintf (file, "BBS:%ld, ", n_bbs); | |
1121 | fprintf (file, "LOOPS:%ld, ", n_loops); | |
1122 | fprintf (file, "CONDITIONS:%ld, ", n_conditions); | |
1123 | fprintf (file, "STMTS:%ld)\n", n_stmts); | |
1124 | fprintf (file, "\nBefore limit_scops SCoP profiling statistics ("); | |
1125 | fprintf (file, "BBS:%ld, ", n_p_bbs); | |
1126 | fprintf (file, "LOOPS:%ld, ", n_p_loops); | |
1127 | fprintf (file, "CONDITIONS:%ld, ", n_p_conditions); | |
1128 | fprintf (file, "STMTS:%ld)\n", n_p_stmts); | |
1129 | } | |
1130 | ||
1131 | /* Print statistics for SCOPS to FILE. */ | |
1132 | ||
1133 | static void | |
1134 | print_graphite_statistics (FILE* file, VEC (scop_p, heap) *scops) | |
1135 | { | |
1136 | int i; | |
1137 | scop_p scop; | |
1138 | ||
ac47786e | 1139 | FOR_EACH_VEC_ELT (scop_p, scops, i, scop) |
2abae5f1 SP |
1140 | print_graphite_scop_statistics (file, scop); |
1141 | } | |
1142 | ||
2abae5f1 SP |
1143 | /* We limit all SCoPs to SCoPs, that are completely surrounded by a loop. |
1144 | ||
1145 | Example: | |
1146 | ||
1147 | for (i | | |
1148 | { | | |
1149 | for (j | SCoP 1 | |
1150 | for (k | | |
1151 | } | | |
1152 | ||
1153 | * SCoP frontier, as this line is not surrounded by any loop. * | |
1154 | ||
1155 | for (l | SCoP 2 | |
1156 | ||
1157 | This is necessary as scalar evolution and parameter detection need a | |
1158 | outermost loop to initialize parameters correctly. | |
1159 | ||
1160 | TODO: FIX scalar evolution and parameter detection to allow more flexible | |
1161 | SCoP frontiers. */ | |
1162 | ||
1163 | static void | |
1164 | limit_scops (VEC (scop_p, heap) **scops) | |
1165 | { | |
1166 | VEC (sd_region, heap) *regions = VEC_alloc (sd_region, heap, 3); | |
1167 | ||
1168 | int i; | |
1169 | scop_p scop; | |
1170 | ||
ac47786e | 1171 | FOR_EACH_VEC_ELT (scop_p, *scops, i, scop) |
2abae5f1 SP |
1172 | { |
1173 | int j; | |
1174 | loop_p loop; | |
1175 | sese region = SCOP_REGION (scop); | |
2abae5f1 SP |
1176 | build_sese_loop_nests (region); |
1177 | ||
ac47786e | 1178 | FOR_EACH_VEC_ELT (loop_p, SESE_LOOP_NEST (region), j, loop) |
2abae5f1 SP |
1179 | if (!loop_in_sese_p (loop_outer (loop), region) |
1180 | && single_exit (loop)) | |
1181 | { | |
1182 | sd_region open_scop; | |
1183 | open_scop.entry = loop->header; | |
1184 | open_scop.exit = single_exit (loop)->dest; | |
1185 | ||
1186 | /* This is a hack on top of the limit_scops hack. The | |
1187 | limit_scops hack should disappear all together. */ | |
1188 | if (single_succ_p (open_scop.exit) | |
1189 | && contains_only_close_phi_nodes (open_scop.exit)) | |
1190 | open_scop.exit = single_succ_edge (open_scop.exit)->dest; | |
1191 | ||
1192 | VEC_safe_push (sd_region, heap, regions, &open_scop); | |
1193 | } | |
1194 | } | |
1195 | ||
7a521ff2 | 1196 | free_scops (*scops); |
2abae5f1 SP |
1197 | *scops = VEC_alloc (scop_p, heap, 3); |
1198 | ||
1199 | create_sese_edges (regions); | |
1200 | build_graphite_scops (regions, scops); | |
1201 | VEC_free (sd_region, heap, regions); | |
1202 | } | |
1203 | ||
3a292d59 SP |
1204 | /* Returns true when P1 and P2 are close phis with the same |
1205 | argument. */ | |
1206 | ||
1207 | static inline bool | |
1208 | same_close_phi_node (gimple p1, gimple p2) | |
1209 | { | |
1210 | return operand_equal_p (gimple_phi_arg_def (p1, 0), | |
1211 | gimple_phi_arg_def (p2, 0), 0); | |
1212 | } | |
1213 | ||
1214 | /* Remove the close phi node at GSI and replace its rhs with the rhs | |
1215 | of PHI. */ | |
1216 | ||
1217 | static void | |
1218 | remove_duplicate_close_phi (gimple phi, gimple_stmt_iterator *gsi) | |
1219 | { | |
1220 | gimple use_stmt; | |
1221 | use_operand_p use_p; | |
1222 | imm_use_iterator imm_iter; | |
1223 | tree res = gimple_phi_result (phi); | |
1224 | tree def = gimple_phi_result (gsi_stmt (*gsi)); | |
1225 | ||
1226 | gcc_assert (same_close_phi_node (phi, gsi_stmt (*gsi))); | |
1227 | ||
1228 | FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, def) | |
1229 | { | |
1230 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) | |
1231 | SET_USE (use_p, res); | |
1232 | ||
1233 | update_stmt (use_stmt); | |
1234 | } | |
1235 | ||
1236 | remove_phi_node (gsi, true); | |
1237 | } | |
1238 | ||
1239 | /* Removes all the close phi duplicates from BB. */ | |
1240 | ||
1241 | static void | |
1242 | make_close_phi_nodes_unique (basic_block bb) | |
1243 | { | |
1244 | gimple_stmt_iterator psi; | |
1245 | ||
1246 | for (psi = gsi_start_phis (bb); !gsi_end_p (psi); gsi_next (&psi)) | |
1247 | { | |
1248 | gimple_stmt_iterator gsi = psi; | |
1249 | gimple phi = gsi_stmt (psi); | |
1250 | ||
1251 | /* At this point, PHI should be a close phi in normal form. */ | |
1252 | gcc_assert (gimple_phi_num_args (phi) == 1); | |
1253 | ||
1254 | /* Iterate over the next phis and remove duplicates. */ | |
1255 | gsi_next (&gsi); | |
1256 | while (!gsi_end_p (gsi)) | |
1257 | if (same_close_phi_node (phi, gsi_stmt (gsi))) | |
1258 | remove_duplicate_close_phi (phi, &gsi); | |
1259 | else | |
1260 | gsi_next (&gsi); | |
1261 | } | |
1262 | } | |
1263 | ||
2abae5f1 SP |
1264 | /* Transforms LOOP to the canonical loop closed SSA form. */ |
1265 | ||
1266 | static void | |
1267 | canonicalize_loop_closed_ssa (loop_p loop) | |
1268 | { | |
1269 | edge e = single_exit (loop); | |
1270 | basic_block bb; | |
1271 | ||
1272 | if (!e || e->flags & EDGE_ABNORMAL) | |
1273 | return; | |
1274 | ||
1275 | bb = e->dest; | |
1276 | ||
1277 | if (VEC_length (edge, bb->preds) == 1) | |
3a292d59 SP |
1278 | { |
1279 | e = split_block_after_labels (bb); | |
1280 | make_close_phi_nodes_unique (e->src); | |
1281 | } | |
2abae5f1 SP |
1282 | else |
1283 | { | |
1284 | gimple_stmt_iterator psi; | |
1285 | basic_block close = split_edge (e); | |
1286 | ||
1287 | e = single_succ_edge (close); | |
1288 | ||
1289 | for (psi = gsi_start_phis (bb); !gsi_end_p (psi); gsi_next (&psi)) | |
1290 | { | |
1291 | gimple phi = gsi_stmt (psi); | |
1292 | unsigned i; | |
1293 | ||
1294 | for (i = 0; i < gimple_phi_num_args (phi); i++) | |
1295 | if (gimple_phi_arg_edge (phi, i) == e) | |
1296 | { | |
1297 | tree res, arg = gimple_phi_arg_def (phi, i); | |
1298 | use_operand_p use_p; | |
1299 | gimple close_phi; | |
1300 | ||
1301 | if (TREE_CODE (arg) != SSA_NAME) | |
1302 | continue; | |
1303 | ||
1304 | close_phi = create_phi_node (arg, close); | |
1305 | res = create_new_def_for (gimple_phi_result (close_phi), | |
1306 | close_phi, | |
1307 | gimple_phi_result_ptr (close_phi)); | |
1308 | add_phi_arg (close_phi, arg, | |
1309 | gimple_phi_arg_edge (close_phi, 0), | |
1310 | UNKNOWN_LOCATION); | |
1311 | use_p = gimple_phi_arg_imm_use_ptr (phi, i); | |
1312 | replace_exp (use_p, res); | |
1313 | update_stmt (phi); | |
1314 | } | |
1315 | } | |
3a292d59 SP |
1316 | |
1317 | make_close_phi_nodes_unique (close); | |
2abae5f1 | 1318 | } |
1c3ba85b SP |
1319 | |
1320 | /* The code above does not properly handle changes in the post dominance | |
1321 | information (yet). */ | |
1322 | free_dominance_info (CDI_POST_DOMINATORS); | |
2abae5f1 SP |
1323 | } |
1324 | ||
1325 | /* Converts the current loop closed SSA form to a canonical form | |
1326 | expected by the Graphite code generation. | |
1327 | ||
1328 | The loop closed SSA form has the following invariant: a variable | |
1329 | defined in a loop that is used outside the loop appears only in the | |
1330 | phi nodes in the destination of the loop exit. These phi nodes are | |
1331 | called close phi nodes. | |
1332 | ||
1333 | The canonical loop closed SSA form contains the extra invariants: | |
1334 | ||
1335 | - when the loop contains only one exit, the close phi nodes contain | |
1336 | only one argument. That implies that the basic block that contains | |
1337 | the close phi nodes has only one predecessor, that is a basic block | |
1338 | in the loop. | |
1339 | ||
1340 | - the basic block containing the close phi nodes does not contain | |
1341 | other statements. | |
3a292d59 SP |
1342 | |
1343 | - there exist only one phi node per definition in the loop. | |
2abae5f1 SP |
1344 | */ |
1345 | ||
1346 | static void | |
1347 | canonicalize_loop_closed_ssa_form (void) | |
1348 | { | |
1349 | loop_iterator li; | |
1350 | loop_p loop; | |
1351 | ||
1352 | #ifdef ENABLE_CHECKING | |
a3b9e73c | 1353 | verify_loop_closed_ssa (true); |
2abae5f1 SP |
1354 | #endif |
1355 | ||
1356 | FOR_EACH_LOOP (li, loop, 0) | |
1357 | canonicalize_loop_closed_ssa (loop); | |
1358 | ||
1359 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); | |
1360 | update_ssa (TODO_update_ssa); | |
1361 | ||
1362 | #ifdef ENABLE_CHECKING | |
a3b9e73c | 1363 | verify_loop_closed_ssa (true); |
2abae5f1 SP |
1364 | #endif |
1365 | } | |
1366 | ||
1367 | /* Find Static Control Parts (SCoP) in the current function and pushes | |
1368 | them to SCOPS. */ | |
1369 | ||
1370 | void | |
1371 | build_scops (VEC (scop_p, heap) **scops) | |
1372 | { | |
1373 | struct loop *loop = current_loops->tree_root; | |
1374 | VEC (sd_region, heap) *regions = VEC_alloc (sd_region, heap, 3); | |
1375 | ||
1376 | canonicalize_loop_closed_ssa_form (); | |
1377 | build_scops_1 (single_succ (ENTRY_BLOCK_PTR), ENTRY_BLOCK_PTR->loop_father, | |
4caa8e21 | 1378 | ®ions, loop); |
2abae5f1 SP |
1379 | create_sese_edges (regions); |
1380 | build_graphite_scops (regions, scops); | |
1381 | ||
1382 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1383 | print_graphite_statistics (dump_file, *scops); | |
1384 | ||
1385 | limit_scops (scops); | |
1386 | VEC_free (sd_region, heap, regions); | |
1387 | ||
1388 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1389 | fprintf (dump_file, "\nnumber of SCoPs: %d\n", | |
1390 | VEC_length (scop_p, *scops)); | |
1391 | } | |
1392 | ||
afae0207 SP |
1393 | /* Pretty print to FILE all the SCoPs in DOT format and mark them with |
1394 | different colors. If there are not enough colors, paint the | |
1395 | remaining SCoPs in gray. | |
1396 | ||
2abae5f1 | 1397 | Special nodes: |
afae0207 SP |
1398 | - "*" after the node number denotes the entry of a SCoP, |
1399 | - "#" after the node number denotes the exit of a SCoP, | |
1400 | - "()" around the node number denotes the entry or the | |
1401 | exit nodes of the SCOP. These are not part of SCoP. */ | |
2abae5f1 SP |
1402 | |
1403 | static void | |
1404 | dot_all_scops_1 (FILE *file, VEC (scop_p, heap) *scops) | |
1405 | { | |
1406 | basic_block bb; | |
1407 | edge e; | |
1408 | edge_iterator ei; | |
1409 | scop_p scop; | |
1410 | const char* color; | |
1411 | int i; | |
1412 | ||
1413 | /* Disable debugging while printing graph. */ | |
1414 | int tmp_dump_flags = dump_flags; | |
1415 | dump_flags = 0; | |
1416 | ||
1417 | fprintf (file, "digraph all {\n"); | |
1418 | ||
1419 | FOR_ALL_BB (bb) | |
1420 | { | |
1421 | int part_of_scop = false; | |
1422 | ||
1423 | /* Use HTML for every bb label. So we are able to print bbs | |
1424 | which are part of two different SCoPs, with two different | |
1425 | background colors. */ | |
1426 | fprintf (file, "%d [label=<\n <TABLE BORDER=\"0\" CELLBORDER=\"1\" ", | |
1427 | bb->index); | |
1428 | fprintf (file, "CELLSPACING=\"0\">\n"); | |
1429 | ||
1430 | /* Select color for SCoP. */ | |
ac47786e | 1431 | FOR_EACH_VEC_ELT (scop_p, scops, i, scop) |
2abae5f1 SP |
1432 | { |
1433 | sese region = SCOP_REGION (scop); | |
1434 | if (bb_in_sese_p (bb, region) | |
1435 | || (SESE_EXIT_BB (region) == bb) | |
1436 | || (SESE_ENTRY_BB (region) == bb)) | |
1437 | { | |
1438 | switch (i % 17) | |
1439 | { | |
1440 | case 0: /* red */ | |
1441 | color = "#e41a1c"; | |
1442 | break; | |
1443 | case 1: /* blue */ | |
1444 | color = "#377eb8"; | |
1445 | break; | |
1446 | case 2: /* green */ | |
1447 | color = "#4daf4a"; | |
1448 | break; | |
1449 | case 3: /* purple */ | |
1450 | color = "#984ea3"; | |
1451 | break; | |
1452 | case 4: /* orange */ | |
1453 | color = "#ff7f00"; | |
1454 | break; | |
1455 | case 5: /* yellow */ | |
1456 | color = "#ffff33"; | |
1457 | break; | |
1458 | case 6: /* brown */ | |
1459 | color = "#a65628"; | |
1460 | break; | |
1461 | case 7: /* rose */ | |
1462 | color = "#f781bf"; | |
1463 | break; | |
1464 | case 8: | |
1465 | color = "#8dd3c7"; | |
1466 | break; | |
1467 | case 9: | |
1468 | color = "#ffffb3"; | |
1469 | break; | |
1470 | case 10: | |
1471 | color = "#bebada"; | |
1472 | break; | |
1473 | case 11: | |
1474 | color = "#fb8072"; | |
1475 | break; | |
1476 | case 12: | |
1477 | color = "#80b1d3"; | |
1478 | break; | |
1479 | case 13: | |
1480 | color = "#fdb462"; | |
1481 | break; | |
1482 | case 14: | |
1483 | color = "#b3de69"; | |
1484 | break; | |
1485 | case 15: | |
1486 | color = "#fccde5"; | |
1487 | break; | |
1488 | case 16: | |
1489 | color = "#bc80bd"; | |
1490 | break; | |
1491 | default: /* gray */ | |
1492 | color = "#999999"; | |
1493 | } | |
1494 | ||
1495 | fprintf (file, " <TR><TD WIDTH=\"50\" BGCOLOR=\"%s\">", color); | |
1496 | ||
1497 | if (!bb_in_sese_p (bb, region)) | |
1498 | fprintf (file, " ("); | |
1499 | ||
1500 | if (bb == SESE_ENTRY_BB (region) | |
1501 | && bb == SESE_EXIT_BB (region)) | |
1502 | fprintf (file, " %d*# ", bb->index); | |
1503 | else if (bb == SESE_ENTRY_BB (region)) | |
1504 | fprintf (file, " %d* ", bb->index); | |
1505 | else if (bb == SESE_EXIT_BB (region)) | |
1506 | fprintf (file, " %d# ", bb->index); | |
1507 | else | |
1508 | fprintf (file, " %d ", bb->index); | |
1509 | ||
1510 | if (!bb_in_sese_p (bb,region)) | |
1511 | fprintf (file, ")"); | |
1512 | ||
1513 | fprintf (file, "</TD></TR>\n"); | |
1514 | part_of_scop = true; | |
1515 | } | |
1516 | } | |
1517 | ||
1518 | if (!part_of_scop) | |
1519 | { | |
1520 | fprintf (file, " <TR><TD WIDTH=\"50\" BGCOLOR=\"#ffffff\">"); | |
1521 | fprintf (file, " %d </TD></TR>\n", bb->index); | |
1522 | } | |
1523 | fprintf (file, " </TABLE>>, shape=box, style=\"setlinewidth(0)\"]\n"); | |
1524 | } | |
1525 | ||
1526 | FOR_ALL_BB (bb) | |
1527 | { | |
1528 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1529 | fprintf (file, "%d -> %d;\n", bb->index, e->dest->index); | |
1530 | } | |
1531 | ||
1532 | fputs ("}\n\n", file); | |
1533 | ||
1534 | /* Enable debugging again. */ | |
1535 | dump_flags = tmp_dump_flags; | |
1536 | } | |
1537 | ||
1538 | /* Display all SCoPs using dotty. */ | |
1539 | ||
1f424006 | 1540 | DEBUG_FUNCTION void |
2abae5f1 SP |
1541 | dot_all_scops (VEC (scop_p, heap) *scops) |
1542 | { | |
1543 | /* When debugging, enable the following code. This cannot be used | |
1544 | in production compilers because it calls "system". */ | |
1545 | #if 0 | |
1546 | int x; | |
1547 | FILE *stream = fopen ("/tmp/allscops.dot", "w"); | |
1548 | gcc_assert (stream); | |
1549 | ||
1550 | dot_all_scops_1 (stream, scops); | |
1551 | fclose (stream); | |
1552 | ||
4c8f3c48 | 1553 | x = system ("dotty /tmp/allscops.dot &"); |
2abae5f1 SP |
1554 | #else |
1555 | dot_all_scops_1 (stderr, scops); | |
1556 | #endif | |
1557 | } | |
1558 | ||
1559 | /* Display all SCoPs using dotty. */ | |
1560 | ||
1f424006 | 1561 | DEBUG_FUNCTION void |
2abae5f1 SP |
1562 | dot_scop (scop_p scop) |
1563 | { | |
1564 | VEC (scop_p, heap) *scops = NULL; | |
1565 | ||
1566 | if (scop) | |
1567 | VEC_safe_push (scop_p, heap, scops, scop); | |
1568 | ||
1569 | /* When debugging, enable the following code. This cannot be used | |
1570 | in production compilers because it calls "system". */ | |
1571 | #if 0 | |
1572 | { | |
1573 | int x; | |
1574 | FILE *stream = fopen ("/tmp/allscops.dot", "w"); | |
1575 | gcc_assert (stream); | |
1576 | ||
1577 | dot_all_scops_1 (stream, scops); | |
1578 | fclose (stream); | |
4c8f3c48 | 1579 | x = system ("dotty /tmp/allscops.dot &"); |
2abae5f1 SP |
1580 | } |
1581 | #else | |
1582 | dot_all_scops_1 (stderr, scops); | |
1583 | #endif | |
1584 | ||
1585 | VEC_free (scop_p, heap, scops); | |
1586 | } | |
1587 | ||
1588 | #endif |