Mercurial > hg > CbC > CbC_gcc
annotate gcc/tree-loop-distribution.c @ 127:4c56639505ff
fix function.c and add CbC-example Makefile
| author | mir3636 |
|---|---|
| date | Wed, 11 Apr 2018 18:46:58 +0900 |
| parents | 04ced10e8804 |
| children | 84e7813d76e9 |
| rev | line source |
|---|---|
| 0 | 1 /* Loop distribution. |
| 111 | 2 Copyright (C) 2006-2017 Free Software Foundation, Inc. |
| 0 | 3 Contributed by Georges-Andre Silber <Georges-Andre.Silber@ensmp.fr> |
| 4 and Sebastian Pop <sebastian.pop@amd.com>. | |
| 5 | |
| 6 This file is part of GCC. | |
|
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7 |
| 0 | 8 GCC is free software; you can redistribute it and/or modify it |
| 9 under the terms of the GNU General Public License as published by the | |
| 10 Free Software Foundation; either version 3, or (at your option) any | |
| 11 later version. | |
|
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12 |
| 0 | 13 GCC is distributed in the hope that it will be useful, but WITHOUT |
| 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 16 for more details. | |
|
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17 |
| 0 | 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 /* This pass performs loop distribution: for example, the loop | |
| 23 | |
| 24 |DO I = 2, N | |
| 25 | A(I) = B(I) + C | |
| 26 | D(I) = A(I-1)*E | |
| 27 |ENDDO | |
| 28 | |
|
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changeset
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29 is transformed to |
| 0 | 30 |
| 31 |DOALL I = 2, N | |
| 32 | A(I) = B(I) + C | |
| 33 |ENDDO | |
| 34 | | |
| 35 |DOALL I = 2, N | |
| 36 | D(I) = A(I-1)*E | |
| 37 |ENDDO | |
| 38 | |
| 111 | 39 Loop distribution is the dual of loop fusion. It separates statements |
| 40 of a loop (or loop nest) into multiple loops (or loop nests) with the | |
| 41 same loop header. The major goal is to separate statements which may | |
| 42 be vectorized from those that can't. This pass implements distribution | |
| 43 in the following steps: | |
| 44 | |
| 45 1) Seed partitions with specific type statements. For now we support | |
| 46 two types seed statements: statement defining variable used outside | |
| 47 of loop; statement storing to memory. | |
| 48 2) Build reduced dependence graph (RDG) for loop to be distributed. | |
| 49 The vertices (RDG:V) model all statements in the loop and the edges | |
| 50 (RDG:E) model flow and control dependencies between statements. | |
| 51 3) Apart from RDG, compute data dependencies between memory references. | |
| 52 4) Starting from seed statement, build up partition by adding depended | |
| 53 statements according to RDG's dependence information. Partition is | |
| 54 classified as parallel type if it can be executed paralleled; or as | |
| 55 sequential type if it can't. Parallel type partition is further | |
| 56 classified as different builtin kinds if it can be implemented as | |
| 57 builtin function calls. | |
| 58 5) Build partition dependence graph (PG) based on data dependencies. | |
| 59 The vertices (PG:V) model all partitions and the edges (PG:E) model | |
| 60 all data dependencies between every partitions pair. In general, | |
| 61 data dependence is either compilation time known or unknown. In C | |
| 62 family languages, there exists quite amount compilation time unknown | |
| 63 dependencies because of possible alias relation of data references. | |
| 64 We categorize PG's edge to two types: "true" edge that represents | |
| 65 compilation time known data dependencies; "alias" edge for all other | |
| 66 data dependencies. | |
| 67 6) Traverse subgraph of PG as if all "alias" edges don't exist. Merge | |
| 68 partitions in each strong connected component (SCC) correspondingly. | |
| 69 Build new PG for merged partitions. | |
| 70 7) Traverse PG again and this time with both "true" and "alias" edges | |
| 71 included. We try to break SCCs by removing some edges. Because | |
| 72 SCCs by "true" edges are all fused in step 6), we can break SCCs | |
| 73 by removing some "alias" edges. It's NP-hard to choose optimal | |
| 74 edge set, fortunately simple approximation is good enough for us | |
| 75 given the small problem scale. | |
| 76 8) Collect all data dependencies of the removed "alias" edges. Create | |
| 77 runtime alias checks for collected data dependencies. | |
| 78 9) Version loop under the condition of runtime alias checks. Given | |
| 79 loop distribution generally introduces additional overhead, it is | |
| 80 only useful if vectorization is achieved in distributed loop. We | |
| 81 version loop with internal function call IFN_LOOP_DIST_ALIAS. If | |
| 82 no distributed loop can be vectorized, we simply remove distributed | |
| 83 loops and recover to the original one. | |
| 84 | |
| 85 TODO: | |
| 86 1) We only distribute innermost two-level loop nest now. We should | |
| 87 extend it for arbitrary loop nests in the future. | |
| 88 2) We only fuse partitions in SCC now. A better fusion algorithm is | |
| 89 desired to minimize loop overhead, maximize parallelism and maximize | |
| 90 data reuse. */ | |
| 0 | 91 |
| 92 #include "config.h" | |
| 111 | 93 #define INCLUDE_ALGORITHM /* stable_sort */ |
| 0 | 94 #include "system.h" |
| 95 #include "coretypes.h" | |
| 111 | 96 #include "backend.h" |
| 97 #include "tree.h" | |
| 98 #include "gimple.h" | |
| 99 #include "cfghooks.h" | |
| 0 | 100 #include "tree-pass.h" |
| 111 | 101 #include "ssa.h" |
| 102 #include "gimple-pretty-print.h" | |
| 103 #include "fold-const.h" | |
| 104 #include "cfganal.h" | |
| 105 #include "gimple-iterator.h" | |
| 106 #include "gimplify-me.h" | |
| 107 #include "stor-layout.h" | |
| 108 #include "tree-cfg.h" | |
| 109 #include "tree-ssa-loop-manip.h" | |
| 110 #include "tree-ssa-loop-ivopts.h" | |
| 111 #include "tree-ssa-loop.h" | |
| 112 #include "tree-into-ssa.h" | |
| 113 #include "tree-ssa.h" | |
| 114 #include "cfgloop.h" | |
| 115 #include "tree-scalar-evolution.h" | |
| 116 #include "params.h" | |
| 117 #include "tree-vectorizer.h" | |
| 118 | |
| 119 | |
| 120 #define MAX_DATAREFS_NUM \ | |
| 121 ((unsigned) PARAM_VALUE (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS)) | |
| 122 | |
| 123 /* Threshold controlling number of distributed partitions. Given it may | |
| 124 be unnecessary if a memory stream cost model is invented in the future, | |
| 125 we define it as a temporary macro, rather than a parameter. */ | |
| 126 #define NUM_PARTITION_THRESHOLD (4) | |
| 127 | |
| 128 /* Hashtable helpers. */ | |
| 129 | |
| 130 struct ddr_hasher : nofree_ptr_hash <struct data_dependence_relation> | |
| 131 { | |
| 132 static inline hashval_t hash (const data_dependence_relation *); | |
| 133 static inline bool equal (const data_dependence_relation *, | |
| 134 const data_dependence_relation *); | |
| 135 }; | |
| 136 | |
| 137 /* Hash function for data dependence. */ | |
| 138 | |
| 139 inline hashval_t | |
| 140 ddr_hasher::hash (const data_dependence_relation *ddr) | |
| 141 { | |
| 142 inchash::hash h; | |
| 143 h.add_ptr (DDR_A (ddr)); | |
| 144 h.add_ptr (DDR_B (ddr)); | |
| 145 return h.end (); | |
| 146 } | |
| 147 | |
| 148 /* Hash table equality function for data dependence. */ | |
| 149 | |
| 150 inline bool | |
| 151 ddr_hasher::equal (const data_dependence_relation *ddr1, | |
| 152 const data_dependence_relation *ddr2) | |
| 153 { | |
| 154 return (DDR_A (ddr1) == DDR_A (ddr2) && DDR_B (ddr1) == DDR_B (ddr2)); | |
| 155 } | |
| 156 | |
| 157 /* The loop (nest) to be distributed. */ | |
| 158 static vec<loop_p> loop_nest; | |
| 159 | |
| 160 /* Vector of data references in the loop to be distributed. */ | |
| 161 static vec<data_reference_p> datarefs_vec; | |
| 162 | |
| 163 /* Store index of data reference in aux field. */ | |
| 164 #define DR_INDEX(dr) ((uintptr_t) (dr)->aux) | |
| 165 | |
| 166 /* Hash table for data dependence relation in the loop to be distributed. */ | |
| 167 static hash_table<ddr_hasher> *ddrs_table; | |
| 168 | |
| 169 /* A Reduced Dependence Graph (RDG) vertex representing a statement. */ | |
| 170 struct rdg_vertex | |
| 171 { | |
| 172 /* The statement represented by this vertex. */ | |
| 173 gimple *stmt; | |
| 174 | |
| 175 /* Vector of data-references in this statement. */ | |
| 176 vec<data_reference_p> datarefs; | |
| 177 | |
| 178 /* True when the statement contains a write to memory. */ | |
| 179 bool has_mem_write; | |
| 180 | |
| 181 /* True when the statement contains a read from memory. */ | |
| 182 bool has_mem_reads; | |
| 183 }; | |
| 184 | |
| 185 #define RDGV_STMT(V) ((struct rdg_vertex *) ((V)->data))->stmt | |
| 186 #define RDGV_DATAREFS(V) ((struct rdg_vertex *) ((V)->data))->datarefs | |
| 187 #define RDGV_HAS_MEM_WRITE(V) ((struct rdg_vertex *) ((V)->data))->has_mem_write | |
| 188 #define RDGV_HAS_MEM_READS(V) ((struct rdg_vertex *) ((V)->data))->has_mem_reads | |
| 189 #define RDG_STMT(RDG, I) RDGV_STMT (&(RDG->vertices[I])) | |
| 190 #define RDG_DATAREFS(RDG, I) RDGV_DATAREFS (&(RDG->vertices[I])) | |
| 191 #define RDG_MEM_WRITE_STMT(RDG, I) RDGV_HAS_MEM_WRITE (&(RDG->vertices[I])) | |
| 192 #define RDG_MEM_READS_STMT(RDG, I) RDGV_HAS_MEM_READS (&(RDG->vertices[I])) | |
| 193 | |
| 194 /* Data dependence type. */ | |
| 195 | |
| 196 enum rdg_dep_type | |
| 197 { | |
| 198 /* Read After Write (RAW). */ | |
| 199 flow_dd = 'f', | |
| 200 | |
| 201 /* Control dependence (execute conditional on). */ | |
| 202 control_dd = 'c' | |
| 203 }; | |
| 204 | |
| 205 /* Dependence information attached to an edge of the RDG. */ | |
| 206 | |
| 207 struct rdg_edge | |
| 208 { | |
| 209 /* Type of the dependence. */ | |
| 210 enum rdg_dep_type type; | |
| 211 }; | |
| 212 | |
| 213 #define RDGE_TYPE(E) ((struct rdg_edge *) ((E)->data))->type | |
| 214 | |
| 215 /* Dump vertex I in RDG to FILE. */ | |
| 216 | |
| 217 static void | |
| 218 dump_rdg_vertex (FILE *file, struct graph *rdg, int i) | |
| 219 { | |
| 220 struct vertex *v = &(rdg->vertices[i]); | |
| 221 struct graph_edge *e; | |
| 222 | |
| 223 fprintf (file, "(vertex %d: (%s%s) (in:", i, | |
| 224 RDG_MEM_WRITE_STMT (rdg, i) ? "w" : "", | |
| 225 RDG_MEM_READS_STMT (rdg, i) ? "r" : ""); | |
| 226 | |
| 227 if (v->pred) | |
| 228 for (e = v->pred; e; e = e->pred_next) | |
| 229 fprintf (file, " %d", e->src); | |
| 230 | |
| 231 fprintf (file, ") (out:"); | |
| 232 | |
| 233 if (v->succ) | |
| 234 for (e = v->succ; e; e = e->succ_next) | |
| 235 fprintf (file, " %d", e->dest); | |
| 236 | |
| 237 fprintf (file, ")\n"); | |
| 238 print_gimple_stmt (file, RDGV_STMT (v), 0, TDF_VOPS|TDF_MEMSYMS); | |
| 239 fprintf (file, ")\n"); | |
| 240 } | |
| 241 | |
| 242 /* Call dump_rdg_vertex on stderr. */ | |
| 243 | |
| 244 DEBUG_FUNCTION void | |
| 245 debug_rdg_vertex (struct graph *rdg, int i) | |
| 246 { | |
| 247 dump_rdg_vertex (stderr, rdg, i); | |
| 248 } | |
| 249 | |
| 250 /* Dump the reduced dependence graph RDG to FILE. */ | |
| 251 | |
| 252 static void | |
| 253 dump_rdg (FILE *file, struct graph *rdg) | |
| 254 { | |
| 255 fprintf (file, "(rdg\n"); | |
| 256 for (int i = 0; i < rdg->n_vertices; i++) | |
| 257 dump_rdg_vertex (file, rdg, i); | |
| 258 fprintf (file, ")\n"); | |
| 259 } | |
| 260 | |
| 261 /* Call dump_rdg on stderr. */ | |
| 262 | |
| 263 DEBUG_FUNCTION void | |
| 264 debug_rdg (struct graph *rdg) | |
| 265 { | |
| 266 dump_rdg (stderr, rdg); | |
| 267 } | |
| 268 | |
| 269 static void | |
| 270 dot_rdg_1 (FILE *file, struct graph *rdg) | |
| 271 { | |
| 272 int i; | |
| 273 pretty_printer buffer; | |
| 274 pp_needs_newline (&buffer) = false; | |
| 275 buffer.buffer->stream = file; | |
| 276 | |
| 277 fprintf (file, "digraph RDG {\n"); | |
| 278 | |
| 279 for (i = 0; i < rdg->n_vertices; i++) | |
| 280 { | |
| 281 struct vertex *v = &(rdg->vertices[i]); | |
| 282 struct graph_edge *e; | |
| 283 | |
| 284 fprintf (file, "%d [label=\"[%d] ", i, i); | |
| 285 pp_gimple_stmt_1 (&buffer, RDGV_STMT (v), 0, TDF_SLIM); | |
| 286 pp_flush (&buffer); | |
| 287 fprintf (file, "\"]\n"); | |
| 288 | |
| 289 /* Highlight reads from memory. */ | |
| 290 if (RDG_MEM_READS_STMT (rdg, i)) | |
| 291 fprintf (file, "%d [style=filled, fillcolor=green]\n", i); | |
| 292 | |
| 293 /* Highlight stores to memory. */ | |
| 294 if (RDG_MEM_WRITE_STMT (rdg, i)) | |
| 295 fprintf (file, "%d [style=filled, fillcolor=red]\n", i); | |
| 296 | |
| 297 if (v->succ) | |
| 298 for (e = v->succ; e; e = e->succ_next) | |
| 299 switch (RDGE_TYPE (e)) | |
| 300 { | |
| 301 case flow_dd: | |
| 302 /* These are the most common dependences: don't print these. */ | |
| 303 fprintf (file, "%d -> %d \n", i, e->dest); | |
| 304 break; | |
| 305 | |
| 306 case control_dd: | |
| 307 fprintf (file, "%d -> %d [label=control] \n", i, e->dest); | |
| 308 break; | |
| 309 | |
| 310 default: | |
| 311 gcc_unreachable (); | |
| 312 } | |
| 313 } | |
| 314 | |
| 315 fprintf (file, "}\n\n"); | |
| 316 } | |
| 317 | |
| 318 /* Display the Reduced Dependence Graph using dotty. */ | |
| 319 | |
| 320 DEBUG_FUNCTION void | |
| 321 dot_rdg (struct graph *rdg) | |
| 322 { | |
| 323 /* When debugging, you may want to enable the following code. */ | |
| 324 #ifdef HAVE_POPEN | |
| 325 FILE *file = popen ("dot -Tx11", "w"); | |
| 326 if (!file) | |
| 327 return; | |
| 328 dot_rdg_1 (file, rdg); | |
| 329 fflush (file); | |
| 330 close (fileno (file)); | |
| 331 pclose (file); | |
| 332 #else | |
| 333 dot_rdg_1 (stderr, rdg); | |
| 334 #endif | |
| 335 } | |
| 336 | |
| 337 /* Returns the index of STMT in RDG. */ | |
| 338 | |
| 339 static int | |
| 340 rdg_vertex_for_stmt (struct graph *rdg ATTRIBUTE_UNUSED, gimple *stmt) | |
| 341 { | |
| 342 int index = gimple_uid (stmt); | |
| 343 gcc_checking_assert (index == -1 || RDG_STMT (rdg, index) == stmt); | |
| 344 return index; | |
| 345 } | |
| 346 | |
| 347 /* Creates dependence edges in RDG for all the uses of DEF. IDEF is | |
| 348 the index of DEF in RDG. */ | |
| 349 | |
| 350 static void | |
| 351 create_rdg_edges_for_scalar (struct graph *rdg, tree def, int idef) | |
| 352 { | |
| 353 use_operand_p imm_use_p; | |
| 354 imm_use_iterator iterator; | |
| 355 | |
| 356 FOR_EACH_IMM_USE_FAST (imm_use_p, iterator, def) | |
| 357 { | |
| 358 struct graph_edge *e; | |
| 359 int use = rdg_vertex_for_stmt (rdg, USE_STMT (imm_use_p)); | |
| 360 | |
| 361 if (use < 0) | |
| 362 continue; | |
| 363 | |
| 364 e = add_edge (rdg, idef, use); | |
| 365 e->data = XNEW (struct rdg_edge); | |
| 366 RDGE_TYPE (e) = flow_dd; | |
| 367 } | |
| 368 } | |
| 369 | |
| 370 /* Creates an edge for the control dependences of BB to the vertex V. */ | |
| 371 | |
| 372 static void | |
| 373 create_edge_for_control_dependence (struct graph *rdg, basic_block bb, | |
| 374 int v, control_dependences *cd) | |
| 375 { | |
| 376 bitmap_iterator bi; | |
| 377 unsigned edge_n; | |
| 378 EXECUTE_IF_SET_IN_BITMAP (cd->get_edges_dependent_on (bb->index), | |
| 379 0, edge_n, bi) | |
| 380 { | |
| 381 basic_block cond_bb = cd->get_edge_src (edge_n); | |
| 382 gimple *stmt = last_stmt (cond_bb); | |
| 383 if (stmt && is_ctrl_stmt (stmt)) | |
| 384 { | |
| 385 struct graph_edge *e; | |
| 386 int c = rdg_vertex_for_stmt (rdg, stmt); | |
| 387 if (c < 0) | |
| 388 continue; | |
| 389 | |
| 390 e = add_edge (rdg, c, v); | |
| 391 e->data = XNEW (struct rdg_edge); | |
| 392 RDGE_TYPE (e) = control_dd; | |
| 393 } | |
| 394 } | |
| 395 } | |
| 396 | |
| 397 /* Creates the edges of the reduced dependence graph RDG. */ | |
| 0 | 398 |
| 399 static void | |
| 111 | 400 create_rdg_flow_edges (struct graph *rdg) |
| 0 | 401 { |
| 111 | 402 int i; |
| 403 def_operand_p def_p; | |
| 404 ssa_op_iter iter; | |
| 405 | |
| 406 for (i = 0; i < rdg->n_vertices; i++) | |
| 407 FOR_EACH_PHI_OR_STMT_DEF (def_p, RDG_STMT (rdg, i), | |
| 408 iter, SSA_OP_DEF) | |
| 409 create_rdg_edges_for_scalar (rdg, DEF_FROM_PTR (def_p), i); | |
| 410 } | |
| 411 | |
| 412 /* Creates the edges of the reduced dependence graph RDG. */ | |
| 413 | |
| 414 static void | |
| 415 create_rdg_cd_edges (struct graph *rdg, control_dependences *cd, loop_p loop) | |
| 416 { | |
| 417 int i; | |
| 418 | |
| 419 for (i = 0; i < rdg->n_vertices; i++) | |
| 0 | 420 { |
| 111 | 421 gimple *stmt = RDG_STMT (rdg, i); |
| 422 if (gimple_code (stmt) == GIMPLE_PHI) | |
| 0 | 423 { |
| 111 | 424 edge_iterator ei; |
| 425 edge e; | |
| 426 FOR_EACH_EDGE (e, ei, gimple_bb (stmt)->preds) | |
| 427 if (flow_bb_inside_loop_p (loop, e->src)) | |
| 428 create_edge_for_control_dependence (rdg, e->src, i, cd); | |
| 0 | 429 } |
| 430 else | |
| 111 | 431 create_edge_for_control_dependence (rdg, gimple_bb (stmt), i, cd); |
| 432 } | |
| 433 } | |
| 434 | |
| 435 /* Build the vertices of the reduced dependence graph RDG. Return false | |
| 436 if that failed. */ | |
| 437 | |
| 438 static bool | |
| 439 create_rdg_vertices (struct graph *rdg, vec<gimple *> stmts, loop_p loop) | |
| 440 { | |
| 441 int i; | |
| 442 gimple *stmt; | |
| 443 | |
| 444 FOR_EACH_VEC_ELT (stmts, i, stmt) | |
| 445 { | |
| 446 struct vertex *v = &(rdg->vertices[i]); | |
| 447 | |
| 448 /* Record statement to vertex mapping. */ | |
| 449 gimple_set_uid (stmt, i); | |
| 450 | |
| 451 v->data = XNEW (struct rdg_vertex); | |
| 452 RDGV_STMT (v) = stmt; | |
| 453 RDGV_DATAREFS (v).create (0); | |
| 454 RDGV_HAS_MEM_WRITE (v) = false; | |
| 455 RDGV_HAS_MEM_READS (v) = false; | |
| 456 if (gimple_code (stmt) == GIMPLE_PHI) | |
| 457 continue; | |
| 458 | |
| 459 unsigned drp = datarefs_vec.length (); | |
| 460 if (!find_data_references_in_stmt (loop, stmt, &datarefs_vec)) | |
| 461 return false; | |
| 462 for (unsigned j = drp; j < datarefs_vec.length (); ++j) | |
| 463 { | |
| 464 data_reference_p dr = datarefs_vec[j]; | |
| 465 if (DR_IS_READ (dr)) | |
| 466 RDGV_HAS_MEM_READS (v) = true; | |
| 467 else | |
| 468 RDGV_HAS_MEM_WRITE (v) = true; | |
| 469 RDGV_DATAREFS (v).safe_push (dr); | |
| 470 } | |
| 471 } | |
| 472 return true; | |
| 473 } | |
| 474 | |
| 475 /* Array mapping basic block's index to its topological order. */ | |
| 476 static int *bb_top_order_index; | |
| 477 /* And size of the array. */ | |
| 478 static int bb_top_order_index_size; | |
| 479 | |
| 480 /* If X has a smaller topological sort number than Y, returns -1; | |
| 481 if greater, returns 1. */ | |
| 482 | |
| 483 static int | |
| 484 bb_top_order_cmp (const void *x, const void *y) | |
| 485 { | |
| 486 basic_block bb1 = *(const basic_block *) x; | |
| 487 basic_block bb2 = *(const basic_block *) y; | |
| 488 | |
| 489 gcc_assert (bb1->index < bb_top_order_index_size | |
| 490 && bb2->index < bb_top_order_index_size); | |
| 491 gcc_assert (bb1 == bb2 | |
| 492 || bb_top_order_index[bb1->index] | |
| 493 != bb_top_order_index[bb2->index]); | |
| 494 | |
| 495 return (bb_top_order_index[bb1->index] - bb_top_order_index[bb2->index]); | |
| 496 } | |
| 497 | |
| 498 /* Initialize STMTS with all the statements of LOOP. We use topological | |
| 499 order to discover all statements. The order is important because | |
| 500 generate_loops_for_partition is using the same traversal for identifying | |
| 501 statements in loop copies. */ | |
| 502 | |
| 503 static void | |
| 504 stmts_from_loop (struct loop *loop, vec<gimple *> *stmts) | |
| 505 { | |
| 506 unsigned int i; | |
| 507 basic_block *bbs = get_loop_body_in_custom_order (loop, bb_top_order_cmp); | |
| 508 | |
| 509 for (i = 0; i < loop->num_nodes; i++) | |
| 510 { | |
| 511 basic_block bb = bbs[i]; | |
| 512 | |
| 513 for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); | |
| 514 gsi_next (&bsi)) | |
| 515 if (!virtual_operand_p (gimple_phi_result (bsi.phi ()))) | |
| 516 stmts->safe_push (bsi.phi ()); | |
| 517 | |
| 518 for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); | |
| 519 gsi_next (&bsi)) | |
| 520 { | |
| 521 gimple *stmt = gsi_stmt (bsi); | |
| 522 if (gimple_code (stmt) != GIMPLE_LABEL && !is_gimple_debug (stmt)) | |
| 523 stmts->safe_push (stmt); | |
| 524 } | |
| 525 } | |
| 526 | |
| 527 free (bbs); | |
| 528 } | |
| 529 | |
| 530 /* Free the reduced dependence graph RDG. */ | |
| 531 | |
| 532 static void | |
| 533 free_rdg (struct graph *rdg) | |
| 534 { | |
| 535 int i; | |
| 536 | |
| 537 for (i = 0; i < rdg->n_vertices; i++) | |
| 538 { | |
| 539 struct vertex *v = &(rdg->vertices[i]); | |
| 540 struct graph_edge *e; | |
| 541 | |
| 542 for (e = v->succ; e; e = e->succ_next) | |
| 543 free (e->data); | |
| 544 | |
| 545 if (v->data) | |
| 546 { | |
| 547 gimple_set_uid (RDGV_STMT (v), -1); | |
| 548 (RDGV_DATAREFS (v)).release (); | |
| 549 free (v->data); | |
| 550 } | |
| 551 } | |
| 552 | |
| 553 free_graph (rdg); | |
| 554 } | |
| 555 | |
| 556 /* Build the Reduced Dependence Graph (RDG) with one vertex per statement of | |
| 557 LOOP, and one edge per flow dependence or control dependence from control | |
| 558 dependence CD. During visiting each statement, data references are also | |
| 559 collected and recorded in global data DATAREFS_VEC. */ | |
| 560 | |
| 561 static struct graph * | |
| 562 build_rdg (struct loop *loop, control_dependences *cd) | |
| 563 { | |
| 564 struct graph *rdg; | |
| 565 | |
| 566 /* Create the RDG vertices from the stmts of the loop nest. */ | |
| 567 auto_vec<gimple *, 10> stmts; | |
| 568 stmts_from_loop (loop, &stmts); | |
| 569 rdg = new_graph (stmts.length ()); | |
| 570 if (!create_rdg_vertices (rdg, stmts, loop)) | |
| 571 { | |
| 572 free_rdg (rdg); | |
| 573 return NULL; | |
| 0 | 574 } |
| 111 | 575 stmts.release (); |
| 576 | |
| 577 create_rdg_flow_edges (rdg); | |
| 578 if (cd) | |
| 579 create_rdg_cd_edges (rdg, cd, loop); | |
| 580 | |
| 581 return rdg; | |
| 582 } | |
| 583 | |
| 584 | |
| 585 /* Kind of distributed loop. */ | |
| 586 enum partition_kind { | |
| 587 PKIND_NORMAL, PKIND_MEMSET, PKIND_MEMCPY, PKIND_MEMMOVE | |
| 588 }; | |
| 589 | |
| 590 /* Type of distributed loop. */ | |
| 591 enum partition_type { | |
| 592 /* The distributed loop can be executed parallelly. */ | |
| 593 PTYPE_PARALLEL = 0, | |
| 594 /* The distributed loop has to be executed sequentially. */ | |
| 595 PTYPE_SEQUENTIAL | |
| 596 }; | |
| 597 | |
| 598 /* Builtin info for loop distribution. */ | |
| 599 struct builtin_info | |
| 600 { | |
| 601 /* data-references a kind != PKIND_NORMAL partition is about. */ | |
| 602 data_reference_p dst_dr; | |
| 603 data_reference_p src_dr; | |
| 604 /* Base address and size of memory objects operated by the builtin. Note | |
| 605 both dest and source memory objects must have the same size. */ | |
| 606 tree dst_base; | |
| 607 tree src_base; | |
| 608 tree size; | |
| 609 /* Base and offset part of dst_base after stripping constant offset. This | |
| 610 is only used in memset builtin distribution for now. */ | |
| 611 tree dst_base_base; | |
| 612 unsigned HOST_WIDE_INT dst_base_offset; | |
| 613 }; | |
| 614 | |
| 615 /* Partition for loop distribution. */ | |
| 616 struct partition | |
| 617 { | |
| 618 /* Statements of the partition. */ | |
| 619 bitmap stmts; | |
| 620 /* True if the partition defines variable which is used outside of loop. */ | |
| 621 bool reduction_p; | |
| 622 enum partition_kind kind; | |
| 623 enum partition_type type; | |
| 624 /* Data references in the partition. */ | |
| 625 bitmap datarefs; | |
| 626 /* Information of builtin parition. */ | |
| 627 struct builtin_info *builtin; | |
| 628 }; | |
| 629 | |
| 630 | |
| 631 /* Allocate and initialize a partition from BITMAP. */ | |
| 632 | |
| 633 static partition * | |
| 634 partition_alloc (void) | |
| 635 { | |
| 636 partition *partition = XCNEW (struct partition); | |
| 637 partition->stmts = BITMAP_ALLOC (NULL); | |
| 638 partition->reduction_p = false; | |
| 639 partition->kind = PKIND_NORMAL; | |
| 640 partition->datarefs = BITMAP_ALLOC (NULL); | |
| 641 return partition; | |
| 642 } | |
| 643 | |
| 644 /* Free PARTITION. */ | |
| 645 | |
| 646 static void | |
| 647 partition_free (partition *partition) | |
| 648 { | |
| 649 BITMAP_FREE (partition->stmts); | |
| 650 BITMAP_FREE (partition->datarefs); | |
| 651 if (partition->builtin) | |
| 652 free (partition->builtin); | |
| 653 | |
| 654 free (partition); | |
| 655 } | |
| 656 | |
| 657 /* Returns true if the partition can be generated as a builtin. */ | |
| 658 | |
| 659 static bool | |
| 660 partition_builtin_p (partition *partition) | |
| 661 { | |
| 662 return partition->kind != PKIND_NORMAL; | |
| 663 } | |
| 664 | |
| 665 /* Returns true if the partition contains a reduction. */ | |
| 666 | |
| 667 static bool | |
| 668 partition_reduction_p (partition *partition) | |
| 669 { | |
| 670 return partition->reduction_p; | |
| 671 } | |
| 672 | |
| 673 /* Partitions are fused because of different reasons. */ | |
| 674 enum fuse_type | |
| 675 { | |
| 676 FUSE_NON_BUILTIN = 0, | |
| 677 FUSE_REDUCTION = 1, | |
| 678 FUSE_SHARE_REF = 2, | |
| 679 FUSE_SAME_SCC = 3, | |
| 680 FUSE_FINALIZE = 4 | |
| 681 }; | |
| 682 | |
| 683 /* Description on different fusing reason. */ | |
| 684 static const char *fuse_message[] = { | |
| 685 "they are non-builtins", | |
| 686 "they have reductions", | |
| 687 "they have shared memory refs", | |
| 688 "they are in the same dependence scc", | |
| 689 "there is no point to distribute loop"}; | |
| 690 | |
| 691 static void | |
| 692 update_type_for_merge (struct graph *, partition *, partition *); | |
| 693 | |
| 694 /* Merge PARTITION into the partition DEST. RDG is the reduced dependence | |
| 695 graph and we update type for result partition if it is non-NULL. */ | |
| 696 | |
| 697 static void | |
| 698 partition_merge_into (struct graph *rdg, partition *dest, | |
| 699 partition *partition, enum fuse_type ft) | |
| 700 { | |
| 701 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 702 { | |
| 703 fprintf (dump_file, "Fuse partitions because %s:\n", fuse_message[ft]); | |
| 704 fprintf (dump_file, " Part 1: "); | |
| 705 dump_bitmap (dump_file, dest->stmts); | |
| 706 fprintf (dump_file, " Part 2: "); | |
| 707 dump_bitmap (dump_file, partition->stmts); | |
| 708 } | |
| 709 | |
| 710 dest->kind = PKIND_NORMAL; | |
| 711 if (dest->type == PTYPE_PARALLEL) | |
| 712 dest->type = partition->type; | |
| 713 | |
| 714 bitmap_ior_into (dest->stmts, partition->stmts); | |
| 715 if (partition_reduction_p (partition)) | |
| 716 dest->reduction_p = true; | |
| 717 | |
| 718 /* Further check if any data dependence prevents us from executing the | |
| 719 new partition parallelly. */ | |
| 720 if (dest->type == PTYPE_PARALLEL && rdg != NULL) | |
| 721 update_type_for_merge (rdg, dest, partition); | |
| 722 | |
| 723 bitmap_ior_into (dest->datarefs, partition->datarefs); | |
| 724 } | |
| 725 | |
| 726 | |
| 727 /* Returns true when DEF is an SSA_NAME defined in LOOP and used after | |
| 728 the LOOP. */ | |
| 729 | |
| 730 static bool | |
| 731 ssa_name_has_uses_outside_loop_p (tree def, loop_p loop) | |
| 732 { | |
| 733 imm_use_iterator imm_iter; | |
| 734 use_operand_p use_p; | |
| 735 | |
| 736 FOR_EACH_IMM_USE_FAST (use_p, imm_iter, def) | |
| 737 { | |
| 738 if (is_gimple_debug (USE_STMT (use_p))) | |
| 739 continue; | |
| 740 | |
| 741 basic_block use_bb = gimple_bb (USE_STMT (use_p)); | |
| 742 if (!flow_bb_inside_loop_p (loop, use_bb)) | |
| 743 return true; | |
| 744 } | |
| 745 | |
| 746 return false; | |
| 747 } | |
| 748 | |
| 749 /* Returns true when STMT defines a scalar variable used after the | |
| 750 loop LOOP. */ | |
| 751 | |
| 752 static bool | |
| 753 stmt_has_scalar_dependences_outside_loop (loop_p loop, gimple *stmt) | |
| 754 { | |
| 755 def_operand_p def_p; | |
| 756 ssa_op_iter op_iter; | |
| 757 | |
| 758 if (gimple_code (stmt) == GIMPLE_PHI) | |
| 759 return ssa_name_has_uses_outside_loop_p (gimple_phi_result (stmt), loop); | |
| 760 | |
| 761 FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, op_iter, SSA_OP_DEF) | |
| 762 if (ssa_name_has_uses_outside_loop_p (DEF_FROM_PTR (def_p), loop)) | |
| 763 return true; | |
| 764 | |
| 765 return false; | |
| 0 | 766 } |
| 767 | |
| 768 /* Return a copy of LOOP placed before LOOP. */ | |
| 769 | |
| 770 static struct loop * | |
| 771 copy_loop_before (struct loop *loop) | |
| 772 { | |
| 773 struct loop *res; | |
| 774 edge preheader = loop_preheader_edge (loop); | |
| 775 | |
| 776 initialize_original_copy_tables (); | |
| 111 | 777 res = slpeel_tree_duplicate_loop_to_edge_cfg (loop, NULL, preheader); |
| 778 gcc_assert (res != NULL); | |
| 0 | 779 free_original_copy_tables (); |
| 111 | 780 delete_update_ssa (); |
| 0 | 781 |
| 782 return res; | |
| 783 } | |
| 784 | |
| 785 /* Creates an empty basic block after LOOP. */ | |
| 786 | |
| 787 static void | |
| 788 create_bb_after_loop (struct loop *loop) | |
| 789 { | |
| 790 edge exit = single_exit (loop); | |
| 791 | |
| 792 if (!exit) | |
| 793 return; | |
| 794 | |
| 795 split_edge (exit); | |
| 796 } | |
| 797 | |
| 798 /* Generate code for PARTITION from the code in LOOP. The loop is | |
| 799 copied when COPY_P is true. All the statements not flagged in the | |
| 800 PARTITION bitmap are removed from the loop or from its copy. The | |
| 801 statements are indexed in sequence inside a basic block, and the | |
| 111 | 802 basic blocks of a loop are taken in dom order. */ |
| 803 | |
| 804 static void | |
| 805 generate_loops_for_partition (struct loop *loop, partition *partition, | |
| 806 bool copy_p) | |
| 0 | 807 { |
| 111 | 808 unsigned i; |
| 0 | 809 basic_block *bbs; |
| 810 | |
| 811 if (copy_p) | |
| 812 { | |
| 111 | 813 int orig_loop_num = loop->orig_loop_num; |
| 0 | 814 loop = copy_loop_before (loop); |
| 111 | 815 gcc_assert (loop != NULL); |
| 816 loop->orig_loop_num = orig_loop_num; | |
| 0 | 817 create_preheader (loop, CP_SIMPLE_PREHEADERS); |
| 818 create_bb_after_loop (loop); | |
| 819 } | |
| 111 | 820 else |
| 0 | 821 { |
| 111 | 822 /* Origin number is set to the new versioned loop's num. */ |
| 823 gcc_assert (loop->orig_loop_num != loop->num); | |
| 0 | 824 } |
| 825 | |
| 111 | 826 /* Remove stmts not in the PARTITION bitmap. */ |
| 0 | 827 bbs = get_loop_body_in_dom_order (loop); |
| 828 | |
| 111 | 829 if (MAY_HAVE_DEBUG_STMTS) |
| 830 for (i = 0; i < loop->num_nodes; i++) | |
| 831 { | |
| 832 basic_block bb = bbs[i]; | |
| 833 | |
| 834 for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); | |
| 835 gsi_next (&bsi)) | |
| 836 { | |
| 837 gphi *phi = bsi.phi (); | |
| 838 if (!virtual_operand_p (gimple_phi_result (phi)) | |
| 839 && !bitmap_bit_p (partition->stmts, gimple_uid (phi))) | |
| 840 reset_debug_uses (phi); | |
| 841 } | |
| 842 | |
| 843 for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
| 844 { | |
| 845 gimple *stmt = gsi_stmt (bsi); | |
| 846 if (gimple_code (stmt) != GIMPLE_LABEL | |
| 847 && !is_gimple_debug (stmt) | |
| 848 && !bitmap_bit_p (partition->stmts, gimple_uid (stmt))) | |
| 849 reset_debug_uses (stmt); | |
| 850 } | |
| 851 } | |
| 852 | |
| 0 | 853 for (i = 0; i < loop->num_nodes; i++) |
| 854 { | |
| 855 basic_block bb = bbs[i]; | |
| 111 | 856 edge inner_exit = NULL; |
| 857 | |
| 858 if (loop != bb->loop_father) | |
| 859 inner_exit = single_exit (bb->loop_father); | |
| 860 | |
| 861 for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi);) | |
| 862 { | |
| 863 gphi *phi = bsi.phi (); | |
| 864 if (!virtual_operand_p (gimple_phi_result (phi)) | |
| 865 && !bitmap_bit_p (partition->stmts, gimple_uid (phi))) | |
| 866 remove_phi_node (&bsi, true); | |
| 867 else | |
| 868 gsi_next (&bsi); | |
| 869 } | |
| 870 | |
| 871 for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi);) | |
| 0 | 872 { |
| 111 | 873 gimple *stmt = gsi_stmt (bsi); |
| 874 if (gimple_code (stmt) != GIMPLE_LABEL | |
| 875 && !is_gimple_debug (stmt) | |
| 876 && !bitmap_bit_p (partition->stmts, gimple_uid (stmt))) | |
| 0 | 877 { |
| 111 | 878 /* In distribution of loop nest, if bb is inner loop's exit_bb, |
| 879 we choose its exit edge/path in order to avoid generating | |
| 880 infinite loop. For all other cases, we choose an arbitrary | |
| 881 path through the empty CFG part that this unnecessary | |
| 882 control stmt controls. */ | |
| 883 if (gcond *cond_stmt = dyn_cast <gcond *> (stmt)) | |
| 884 { | |
| 885 if (inner_exit && inner_exit->flags & EDGE_TRUE_VALUE) | |
| 886 gimple_cond_make_true (cond_stmt); | |
| 887 else | |
| 888 gimple_cond_make_false (cond_stmt); | |
| 889 update_stmt (stmt); | |
| 890 } | |
| 891 else if (gimple_code (stmt) == GIMPLE_SWITCH) | |
| 892 { | |
| 893 gswitch *switch_stmt = as_a <gswitch *> (stmt); | |
| 894 gimple_switch_set_index | |
| 895 (switch_stmt, CASE_LOW (gimple_switch_label (switch_stmt, 1))); | |
| 896 update_stmt (stmt); | |
| 897 } | |
| 898 else | |
| 899 { | |
| 900 unlink_stmt_vdef (stmt); | |
| 901 gsi_remove (&bsi, true); | |
| 902 release_defs (stmt); | |
| 903 continue; | |
| 904 } | |
| 0 | 905 } |
| 111 | 906 gsi_next (&bsi); |
| 0 | 907 } |
| 908 } | |
| 909 | |
| 111 | 910 free (bbs); |
| 911 } | |
| 912 | |
| 913 /* If VAL memory representation contains the same value in all bytes, | |
| 914 return that value, otherwise return -1. | |
| 915 E.g. for 0x24242424 return 0x24, for IEEE double | |
| 916 747708026454360457216.0 return 0x44, etc. */ | |
| 917 | |
| 918 static int | |
| 919 const_with_all_bytes_same (tree val) | |
| 920 { | |
| 921 unsigned char buf[64]; | |
| 922 int i, len; | |
| 923 | |
| 924 if (integer_zerop (val) | |
| 925 || (TREE_CODE (val) == CONSTRUCTOR | |
| 926 && !TREE_CLOBBER_P (val) | |
| 927 && CONSTRUCTOR_NELTS (val) == 0)) | |
| 928 return 0; | |
| 929 | |
| 930 if (real_zerop (val)) | |
| 931 { | |
| 932 /* Only return 0 for +0.0, not for -0.0, which doesn't have | |
| 933 an all bytes same memory representation. Don't transform | |
| 934 -0.0 stores into +0.0 even for !HONOR_SIGNED_ZEROS. */ | |
| 935 switch (TREE_CODE (val)) | |
| 936 { | |
| 937 case REAL_CST: | |
| 938 if (!real_isneg (TREE_REAL_CST_PTR (val))) | |
| 939 return 0; | |
| 940 break; | |
| 941 case COMPLEX_CST: | |
| 942 if (!const_with_all_bytes_same (TREE_REALPART (val)) | |
| 943 && !const_with_all_bytes_same (TREE_IMAGPART (val))) | |
| 944 return 0; | |
| 945 break; | |
| 946 case VECTOR_CST: | |
| 947 unsigned int j; | |
| 948 for (j = 0; j < VECTOR_CST_NELTS (val); ++j) | |
| 949 if (const_with_all_bytes_same (VECTOR_CST_ELT (val, j))) | |
| 950 break; | |
| 951 if (j == VECTOR_CST_NELTS (val)) | |
| 952 return 0; | |
| 953 break; | |
| 954 default: | |
| 955 break; | |
| 956 } | |
| 957 } | |
| 958 | |
| 959 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8) | |
| 960 return -1; | |
| 961 | |
| 962 len = native_encode_expr (val, buf, sizeof (buf)); | |
| 963 if (len == 0) | |
| 964 return -1; | |
| 965 for (i = 1; i < len; i++) | |
| 966 if (buf[i] != buf[0]) | |
| 967 return -1; | |
| 968 return buf[0]; | |
| 969 } | |
| 970 | |
| 971 /* Generate a call to memset for PARTITION in LOOP. */ | |
| 972 | |
| 973 static void | |
| 974 generate_memset_builtin (struct loop *loop, partition *partition) | |
| 975 { | |
| 976 gimple_stmt_iterator gsi; | |
| 977 tree mem, fn, nb_bytes; | |
| 978 tree val; | |
| 979 struct builtin_info *builtin = partition->builtin; | |
| 980 gimple *fn_call; | |
| 0 | 981 |
| 982 /* The new statements will be placed before LOOP. */ | |
| 111 | 983 gsi = gsi_last_bb (loop_preheader_edge (loop)->src); |
| 984 | |
| 985 nb_bytes = builtin->size; | |
| 986 nb_bytes = force_gimple_operand_gsi (&gsi, nb_bytes, true, NULL_TREE, | |
| 987 false, GSI_CONTINUE_LINKING); | |
| 988 mem = builtin->dst_base; | |
| 989 mem = force_gimple_operand_gsi (&gsi, mem, true, NULL_TREE, | |
| 990 false, GSI_CONTINUE_LINKING); | |
| 991 | |
| 992 /* This exactly matches the pattern recognition in classify_partition. */ | |
| 993 val = gimple_assign_rhs1 (DR_STMT (builtin->dst_dr)); | |
| 994 /* Handle constants like 0x15151515 and similarly | |
| 995 floating point constants etc. where all bytes are the same. */ | |
| 996 int bytev = const_with_all_bytes_same (val); | |
| 997 if (bytev != -1) | |
| 998 val = build_int_cst (integer_type_node, bytev); | |
| 999 else if (TREE_CODE (val) == INTEGER_CST) | |
| 1000 val = fold_convert (integer_type_node, val); | |
| 1001 else if (!useless_type_conversion_p (integer_type_node, TREE_TYPE (val))) | |
| 1002 { | |
| 1003 tree tem = make_ssa_name (integer_type_node); | |
| 1004 gimple *cstmt = gimple_build_assign (tem, NOP_EXPR, val); | |
| 1005 gsi_insert_after (&gsi, cstmt, GSI_CONTINUE_LINKING); | |
| 1006 val = tem; | |
| 1007 } | |
| 1008 | |
| 1009 fn = build_fold_addr_expr (builtin_decl_implicit (BUILT_IN_MEMSET)); | |
| 1010 fn_call = gimple_build_call (fn, 3, mem, val, nb_bytes); | |
| 1011 gsi_insert_after (&gsi, fn_call, GSI_CONTINUE_LINKING); | |
| 1012 | |
| 1013 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 0 | 1014 { |
| 111 | 1015 fprintf (dump_file, "generated memset"); |
| 1016 if (bytev == 0) | |
| 1017 fprintf (dump_file, " zero\n"); | |
| 1018 else | |
| 1019 fprintf (dump_file, "\n"); | |
| 1020 } | |
| 1021 } | |
| 1022 | |
| 1023 /* Generate a call to memcpy for PARTITION in LOOP. */ | |
| 1024 | |
| 1025 static void | |
| 1026 generate_memcpy_builtin (struct loop *loop, partition *partition) | |
| 1027 { | |
| 1028 gimple_stmt_iterator gsi; | |
| 1029 gimple *fn_call; | |
| 1030 tree dest, src, fn, nb_bytes; | |
| 1031 enum built_in_function kind; | |
| 1032 struct builtin_info *builtin = partition->builtin; | |
| 1033 | |
| 1034 /* The new statements will be placed before LOOP. */ | |
| 1035 gsi = gsi_last_bb (loop_preheader_edge (loop)->src); | |
| 1036 | |
| 1037 nb_bytes = builtin->size; | |
| 1038 nb_bytes = force_gimple_operand_gsi (&gsi, nb_bytes, true, NULL_TREE, | |
| 1039 false, GSI_CONTINUE_LINKING); | |
| 1040 dest = builtin->dst_base; | |
| 1041 src = builtin->src_base; | |
| 1042 if (partition->kind == PKIND_MEMCPY | |
| 1043 || ! ptr_derefs_may_alias_p (dest, src)) | |
| 1044 kind = BUILT_IN_MEMCPY; | |
| 1045 else | |
| 1046 kind = BUILT_IN_MEMMOVE; | |
| 1047 | |
| 1048 dest = force_gimple_operand_gsi (&gsi, dest, true, NULL_TREE, | |
| 1049 false, GSI_CONTINUE_LINKING); | |
| 1050 src = force_gimple_operand_gsi (&gsi, src, true, NULL_TREE, | |
| 1051 false, GSI_CONTINUE_LINKING); | |
| 1052 fn = build_fold_addr_expr (builtin_decl_implicit (kind)); | |
| 1053 fn_call = gimple_build_call (fn, 3, dest, src, nb_bytes); | |
| 1054 gsi_insert_after (&gsi, fn_call, GSI_CONTINUE_LINKING); | |
| 1055 | |
| 1056 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 1057 { | |
| 1058 if (kind == BUILT_IN_MEMCPY) | |
| 1059 fprintf (dump_file, "generated memcpy\n"); | |
| 1060 else | |
| 1061 fprintf (dump_file, "generated memmove\n"); | |
| 0 | 1062 } |
| 1063 } | |
| 1064 | |
| 111 | 1065 /* Remove and destroy the loop LOOP. */ |
| 1066 | |
| 1067 static void | |
| 1068 destroy_loop (struct loop *loop) | |
| 0 | 1069 { |
| 111 | 1070 unsigned nbbs = loop->num_nodes; |
| 1071 edge exit = single_exit (loop); | |
| 1072 basic_block src = loop_preheader_edge (loop)->src, dest = exit->dest; | |
| 1073 basic_block *bbs; | |
| 1074 unsigned i; | |
| 1075 | |
| 1076 bbs = get_loop_body_in_dom_order (loop); | |
| 1077 | |
| 1078 redirect_edge_pred (exit, src); | |
| 1079 exit->flags &= ~(EDGE_TRUE_VALUE|EDGE_FALSE_VALUE); | |
| 1080 exit->flags |= EDGE_FALLTHRU; | |
| 1081 cancel_loop_tree (loop); | |
| 1082 rescan_loop_exit (exit, false, true); | |
| 1083 | |
| 1084 i = nbbs; | |
| 1085 do | |
| 1086 { | |
| 1087 /* We have made sure to not leave any dangling uses of SSA | |
| 1088 names defined in the loop. With the exception of virtuals. | |
| 1089 Make sure we replace all uses of virtual defs that will remain | |
| 1090 outside of the loop with the bare symbol as delete_basic_block | |
| 1091 will release them. */ | |
| 1092 --i; | |
| 1093 for (gphi_iterator gsi = gsi_start_phis (bbs[i]); !gsi_end_p (gsi); | |
| 1094 gsi_next (&gsi)) | |
| 1095 { | |
| 1096 gphi *phi = gsi.phi (); | |
| 1097 if (virtual_operand_p (gimple_phi_result (phi))) | |
| 1098 mark_virtual_phi_result_for_renaming (phi); | |
| 1099 } | |
| 1100 for (gimple_stmt_iterator gsi = gsi_start_bb (bbs[i]); !gsi_end_p (gsi); | |
| 1101 gsi_next (&gsi)) | |
| 1102 { | |
| 1103 gimple *stmt = gsi_stmt (gsi); | |
| 1104 tree vdef = gimple_vdef (stmt); | |
| 1105 if (vdef && TREE_CODE (vdef) == SSA_NAME) | |
| 1106 mark_virtual_operand_for_renaming (vdef); | |
| 1107 } | |
| 1108 delete_basic_block (bbs[i]); | |
| 1109 } | |
| 1110 while (i != 0); | |
| 1111 | |
| 1112 free (bbs); | |
| 1113 | |
| 1114 set_immediate_dominator (CDI_DOMINATORS, dest, | |
| 1115 recompute_dominator (CDI_DOMINATORS, dest)); | |
| 1116 } | |
| 1117 | |
| 1118 /* Generates code for PARTITION. Return whether LOOP needs to be destroyed. */ | |
| 1119 | |
| 1120 static bool | |
| 1121 generate_code_for_partition (struct loop *loop, | |
| 1122 partition *partition, bool copy_p) | |
| 1123 { | |
| 1124 switch (partition->kind) | |
| 1125 { | |
| 1126 case PKIND_NORMAL: | |
| 1127 /* Reductions all have to be in the last partition. */ | |
| 1128 gcc_assert (!partition_reduction_p (partition) | |
| 1129 || !copy_p); | |
| 1130 generate_loops_for_partition (loop, partition, copy_p); | |
| 1131 return false; | |
| 1132 | |
| 1133 case PKIND_MEMSET: | |
| 1134 generate_memset_builtin (loop, partition); | |
| 1135 break; | |
| 1136 | |
| 1137 case PKIND_MEMCPY: | |
| 1138 case PKIND_MEMMOVE: | |
| 1139 generate_memcpy_builtin (loop, partition); | |
| 1140 break; | |
| 1141 | |
| 1142 default: | |
| 1143 gcc_unreachable (); | |
| 1144 } | |
| 1145 | |
| 1146 /* Common tail for partitions we turn into a call. If this was the last | |
| 1147 partition for which we generate code, we have to destroy the loop. */ | |
| 1148 if (!copy_p) | |
| 0 | 1149 return true; |
| 1150 return false; | |
| 1151 } | |
| 1152 | |
| 111 | 1153 /* Return data dependence relation for data references A and B. The two |
| 1154 data references must be in lexicographic order wrto reduced dependence | |
| 1155 graph RDG. We firstly try to find ddr from global ddr hash table. If | |
| 1156 it doesn't exist, compute the ddr and cache it. */ | |
| 1157 | |
| 1158 static data_dependence_relation * | |
| 1159 get_data_dependence (struct graph *rdg, data_reference_p a, data_reference_p b) | |
| 0 | 1160 { |
| 111 | 1161 struct data_dependence_relation ent, **slot; |
| 1162 struct data_dependence_relation *ddr; | |
| 1163 | |
| 1164 gcc_assert (DR_IS_WRITE (a) || DR_IS_WRITE (b)); | |
| 1165 gcc_assert (rdg_vertex_for_stmt (rdg, DR_STMT (a)) | |
| 1166 <= rdg_vertex_for_stmt (rdg, DR_STMT (b))); | |
| 1167 ent.a = a; | |
| 1168 ent.b = b; | |
| 1169 slot = ddrs_table->find_slot (&ent, INSERT); | |
| 1170 if (*slot == NULL) | |
| 1171 { | |
| 1172 ddr = initialize_data_dependence_relation (a, b, loop_nest); | |
| 1173 compute_affine_dependence (ddr, loop_nest[0]); | |
| 1174 *slot = ddr; | |
| 1175 } | |
| 1176 | |
| 1177 return *slot; | |
| 0 | 1178 } |
| 1179 | |
| 111 | 1180 /* In reduced dependence graph RDG for loop distribution, return true if |
| 1181 dependence between references DR1 and DR2 leads to a dependence cycle | |
| 1182 and such dependence cycle can't be resolved by runtime alias check. */ | |
| 0 | 1183 |
| 1184 static bool | |
| 111 | 1185 data_dep_in_cycle_p (struct graph *rdg, |
| 1186 data_reference_p dr1, data_reference_p dr2) | |
| 0 | 1187 { |
| 111 | 1188 struct data_dependence_relation *ddr; |
| 1189 | |
| 1190 /* Re-shuffle data-refs to be in topological order. */ | |
| 1191 if (rdg_vertex_for_stmt (rdg, DR_STMT (dr1)) | |
| 1192 > rdg_vertex_for_stmt (rdg, DR_STMT (dr2))) | |
| 1193 std::swap (dr1, dr2); | |
| 1194 | |
| 1195 ddr = get_data_dependence (rdg, dr1, dr2); | |
| 1196 | |
| 1197 /* In case of no data dependence. */ | |
| 1198 if (DDR_ARE_DEPENDENT (ddr) == chrec_known) | |
| 1199 return false; | |
| 1200 /* For unknown data dependence or known data dependence which can't be | |
| 1201 expressed in classic distance vector, we check if it can be resolved | |
| 1202 by runtime alias check. If yes, we still consider data dependence | |
| 1203 as won't introduce data dependence cycle. */ | |
| 1204 else if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know | |
| 1205 || DDR_NUM_DIST_VECTS (ddr) == 0) | |
| 1206 return !runtime_alias_check_p (ddr, NULL, true); | |
| 1207 else if (DDR_NUM_DIST_VECTS (ddr) > 1) | |
| 1208 return true; | |
| 1209 else if (DDR_REVERSED_P (ddr) | |
| 1210 || lambda_vector_zerop (DDR_DIST_VECT (ddr, 0), 1)) | |
| 1211 return false; | |
| 1212 | |
| 1213 return true; | |
| 0 | 1214 } |
| 1215 | |
| 111 | 1216 /* Given reduced dependence graph RDG, PARTITION1 and PARTITION2, update |
| 1217 PARTITION1's type after merging PARTITION2 into PARTITION1. */ | |
| 0 | 1218 |
| 1219 static void | |
| 111 | 1220 update_type_for_merge (struct graph *rdg, |
| 1221 partition *partition1, partition *partition2) | |
| 0 | 1222 { |
| 111 | 1223 unsigned i, j; |
| 1224 bitmap_iterator bi, bj; | |
| 1225 data_reference_p dr1, dr2; | |
| 1226 | |
| 1227 EXECUTE_IF_SET_IN_BITMAP (partition1->datarefs, 0, i, bi) | |
| 0 | 1228 { |
| 111 | 1229 unsigned start = (partition1 == partition2) ? i + 1 : 0; |
| 1230 | |
| 1231 dr1 = datarefs_vec[i]; | |
| 1232 EXECUTE_IF_SET_IN_BITMAP (partition2->datarefs, start, j, bj) | |
| 0 | 1233 { |
| 111 | 1234 dr2 = datarefs_vec[j]; |
| 1235 if (DR_IS_READ (dr1) && DR_IS_READ (dr2)) | |
| 1236 continue; | |
| 1237 | |
| 1238 /* Partition can only be executed sequentially if there is any | |
| 1239 data dependence cycle. */ | |
| 1240 if (data_dep_in_cycle_p (rdg, dr1, dr2)) | |
| 0 | 1241 { |
| 111 | 1242 partition1->type = PTYPE_SEQUENTIAL; |
| 1243 return; | |
| 0 | 1244 } |
| 1245 } | |
| 1246 } | |
| 1247 } | |
| 1248 | |
| 111 | 1249 /* Returns a partition with all the statements needed for computing |
| 1250 the vertex V of the RDG, also including the loop exit conditions. */ | |
| 1251 | |
| 1252 static partition * | |
| 1253 build_rdg_partition_for_vertex (struct graph *rdg, int v) | |
| 0 | 1254 { |
| 111 | 1255 partition *partition = partition_alloc (); |
| 1256 auto_vec<int, 3> nodes; | |
| 1257 unsigned i, j; | |
| 0 | 1258 int x; |
| 111 | 1259 data_reference_p dr; |
| 1260 | |
| 1261 graphds_dfs (rdg, &v, 1, &nodes, false, NULL); | |
| 1262 | |
| 1263 FOR_EACH_VEC_ELT (nodes, i, x) | |
| 1264 { | |
| 1265 bitmap_set_bit (partition->stmts, x); | |
| 1266 | |
| 1267 for (j = 0; RDG_DATAREFS (rdg, x).iterate (j, &dr); ++j) | |
| 1268 { | |
| 1269 unsigned idx = (unsigned) DR_INDEX (dr); | |
| 1270 gcc_assert (idx < datarefs_vec.length ()); | |
| 1271 | |
| 1272 /* Partition can only be executed sequentially if there is any | |
| 1273 unknown data reference. */ | |
| 1274 if (!DR_BASE_ADDRESS (dr) || !DR_OFFSET (dr) | |
| 1275 || !DR_INIT (dr) || !DR_STEP (dr)) | |
| 1276 partition->type = PTYPE_SEQUENTIAL; | |
| 1277 | |
| 1278 bitmap_set_bit (partition->datarefs, idx); | |
| 1279 } | |
| 1280 } | |
| 1281 | |
| 1282 if (partition->type == PTYPE_SEQUENTIAL) | |
| 1283 return partition; | |
| 1284 | |
| 1285 /* Further check if any data dependence prevents us from executing the | |
| 1286 partition parallelly. */ | |
| 1287 update_type_for_merge (rdg, partition, partition); | |
| 1288 | |
| 1289 return partition; | |
| 0 | 1290 } |
| 1291 | |
| 111 | 1292 /* Given PARTITION of LOOP and RDG, record single load/store data references |
| 1293 for builtin partition in SRC_DR/DST_DR, return false if there is no such | |
| 1294 data references. */ | |
| 1295 | |
| 1296 static bool | |
| 1297 find_single_drs (struct loop *loop, struct graph *rdg, partition *partition, | |
| 1298 data_reference_p *dst_dr, data_reference_p *src_dr) | |
| 0 | 1299 { |
| 1300 unsigned i; | |
| 111 | 1301 data_reference_p single_ld = NULL, single_st = NULL; |
| 0 | 1302 bitmap_iterator bi; |
| 111 | 1303 |
| 1304 EXECUTE_IF_SET_IN_BITMAP (partition->stmts, 0, i, bi) | |
| 0 | 1305 { |
| 111 | 1306 gimple *stmt = RDG_STMT (rdg, i); |
| 1307 data_reference_p dr; | |
| 1308 | |
| 1309 if (gimple_code (stmt) == GIMPLE_PHI) | |
| 1310 continue; | |
| 1311 | |
| 1312 /* Any scalar stmts are ok. */ | |
| 1313 if (!gimple_vuse (stmt)) | |
| 1314 continue; | |
| 1315 | |
| 1316 /* Otherwise just regular loads/stores. */ | |
| 1317 if (!gimple_assign_single_p (stmt)) | |
| 1318 return false; | |
| 1319 | |
| 1320 /* But exactly one store and/or load. */ | |
| 1321 for (unsigned j = 0; RDG_DATAREFS (rdg, i).iterate (j, &dr); ++j) | |
| 1322 { | |
| 1323 tree type = TREE_TYPE (DR_REF (dr)); | |
| 1324 | |
| 1325 /* The memset, memcpy and memmove library calls are only | |
| 1326 able to deal with generic address space. */ | |
| 1327 if (!ADDR_SPACE_GENERIC_P (TYPE_ADDR_SPACE (type))) | |
| 1328 return false; | |
| 1329 | |
| 1330 if (DR_IS_READ (dr)) | |
| 1331 { | |
| 1332 if (single_ld != NULL) | |
| 1333 return false; | |
| 1334 single_ld = dr; | |
| 1335 } | |
| 1336 else | |
| 1337 { | |
| 1338 if (single_st != NULL) | |
| 1339 return false; | |
| 1340 single_st = dr; | |
| 1341 } | |
| 1342 } | |
| 0 | 1343 } |
| 1344 | |
| 111 | 1345 if (!single_st) |
| 1346 return false; | |
| 1347 | |
| 1348 /* Bail out if this is a bitfield memory reference. */ | |
| 1349 if (TREE_CODE (DR_REF (single_st)) == COMPONENT_REF | |
| 1350 && DECL_BIT_FIELD (TREE_OPERAND (DR_REF (single_st), 1))) | |
| 1351 return false; | |
| 1352 | |
| 1353 /* Data reference must be executed exactly once per iteration of each | |
| 1354 loop in the loop nest. We only need to check dominance information | |
| 1355 against the outermost one in a perfect loop nest because a bb can't | |
| 1356 dominate outermost loop's latch without dominating inner loop's. */ | |
| 1357 basic_block bb_st = gimple_bb (DR_STMT (single_st)); | |
| 1358 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb_st)) | |
| 1359 return false; | |
| 1360 | |
| 1361 if (single_ld) | |
| 1362 { | |
| 1363 gimple *store = DR_STMT (single_st), *load = DR_STMT (single_ld); | |
| 1364 /* Direct aggregate copy or via an SSA name temporary. */ | |
| 1365 if (load != store | |
| 1366 && gimple_assign_lhs (load) != gimple_assign_rhs1 (store)) | |
| 1367 return false; | |
| 1368 | |
| 1369 /* Bail out if this is a bitfield memory reference. */ | |
| 1370 if (TREE_CODE (DR_REF (single_ld)) == COMPONENT_REF | |
| 1371 && DECL_BIT_FIELD (TREE_OPERAND (DR_REF (single_ld), 1))) | |
| 1372 return false; | |
| 1373 | |
| 1374 /* Load and store must be in the same loop nest. */ | |
| 1375 basic_block bb_ld = gimple_bb (DR_STMT (single_ld)); | |
| 1376 if (bb_st->loop_father != bb_ld->loop_father) | |
| 1377 return false; | |
| 1378 | |
| 1379 /* Data reference must be executed exactly once per iteration. | |
| 1380 Same as single_st, we only need to check against the outermost | |
| 1381 loop. */ | |
| 1382 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb_ld)) | |
| 1383 return false; | |
| 1384 | |
| 1385 edge e = single_exit (bb_st->loop_father); | |
| 1386 bool dom_ld = dominated_by_p (CDI_DOMINATORS, e->src, bb_ld); | |
| 1387 bool dom_st = dominated_by_p (CDI_DOMINATORS, e->src, bb_st); | |
| 1388 if (dom_ld != dom_st) | |
| 1389 return false; | |
| 1390 } | |
| 1391 | |
| 1392 *src_dr = single_ld; | |
| 1393 *dst_dr = single_st; | |
| 1394 return true; | |
| 0 | 1395 } |
| 1396 | |
| 111 | 1397 /* Given data reference DR in LOOP_NEST, this function checks the enclosing |
| 1398 loops from inner to outer to see if loop's step equals to access size at | |
| 1399 each level of loop. Return true if yes; record access base and size in | |
| 1400 BASE and SIZE; save loop's step at each level of loop in STEPS if it is | |
| 1401 not null. For example: | |
| 1402 | |
| 1403 int arr[100][100][100]; | |
| 1404 for (i = 0; i < 100; i++) ;steps[2] = 40000 | |
| 1405 for (j = 100; j > 0; j--) ;steps[1] = -400 | |
| 1406 for (k = 0; k < 100; k++) ;steps[0] = 4 | |
| 1407 arr[i][j - 1][k] = 0; ;base = &arr, size = 4000000. */ | |
| 1408 | |
| 1409 static bool | |
| 1410 compute_access_range (loop_p loop_nest, data_reference_p dr, tree *base, | |
| 1411 tree *size, vec<tree> *steps = NULL) | |
| 0 | 1412 { |
| 111 | 1413 location_t loc = gimple_location (DR_STMT (dr)); |
| 1414 basic_block bb = gimple_bb (DR_STMT (dr)); | |
| 1415 struct loop *loop = bb->loop_father; | |
| 1416 tree ref = DR_REF (dr); | |
| 1417 tree access_base = build_fold_addr_expr (ref); | |
| 1418 tree access_size = TYPE_SIZE_UNIT (TREE_TYPE (ref)); | |
| 1419 | |
| 1420 do { | |
| 1421 tree scev_fn = analyze_scalar_evolution (loop, access_base); | |
| 1422 if (TREE_CODE (scev_fn) != POLYNOMIAL_CHREC) | |
| 1423 return false; | |
| 1424 | |
| 1425 access_base = CHREC_LEFT (scev_fn); | |
| 1426 if (tree_contains_chrecs (access_base, NULL)) | |
| 1427 return false; | |
| 1428 | |
| 1429 tree scev_step = CHREC_RIGHT (scev_fn); | |
| 1430 /* Only support constant steps. */ | |
| 1431 if (TREE_CODE (scev_step) != INTEGER_CST) | |
| 1432 return false; | |
| 1433 | |
| 1434 enum ev_direction access_dir = scev_direction (scev_fn); | |
| 1435 if (access_dir == EV_DIR_UNKNOWN) | |
| 1436 return false; | |
| 1437 | |
| 1438 if (steps != NULL) | |
| 1439 steps->safe_push (scev_step); | |
| 1440 | |
| 1441 scev_step = fold_convert_loc (loc, sizetype, scev_step); | |
| 1442 /* Compute absolute value of scev step. */ | |
| 1443 if (access_dir == EV_DIR_DECREASES) | |
| 1444 scev_step = fold_build1_loc (loc, NEGATE_EXPR, sizetype, scev_step); | |
| 1445 | |
| 1446 /* At each level of loop, scev step must equal to access size. In other | |
| 1447 words, DR must access consecutive memory between loop iterations. */ | |
| 1448 if (!operand_equal_p (scev_step, access_size, 0)) | |
| 1449 return false; | |
| 1450 | |
| 1451 /* Compute DR's execution times in loop. */ | |
| 1452 tree niters = number_of_latch_executions (loop); | |
| 1453 niters = fold_convert_loc (loc, sizetype, niters); | |
| 1454 if (dominated_by_p (CDI_DOMINATORS, single_exit (loop)->src, bb)) | |
| 1455 niters = size_binop_loc (loc, PLUS_EXPR, niters, size_one_node); | |
| 1456 | |
| 1457 /* Compute DR's overall access size in loop. */ | |
| 1458 access_size = fold_build2_loc (loc, MULT_EXPR, sizetype, | |
| 1459 niters, scev_step); | |
| 1460 /* Adjust base address in case of negative step. */ | |
| 1461 if (access_dir == EV_DIR_DECREASES) | |
| 1462 { | |
| 1463 tree adj = fold_build2_loc (loc, MINUS_EXPR, sizetype, | |
| 1464 scev_step, access_size); | |
| 1465 access_base = fold_build_pointer_plus_loc (loc, access_base, adj); | |
| 1466 } | |
| 1467 } while (loop != loop_nest && (loop = loop_outer (loop)) != NULL); | |
| 1468 | |
| 1469 *base = access_base; | |
| 1470 *size = access_size; | |
| 1471 return true; | |
| 0 | 1472 } |
| 1473 | |
| 111 | 1474 /* Allocate and return builtin struct. Record information like DST_DR, |
| 1475 SRC_DR, DST_BASE, SRC_BASE and SIZE in the allocated struct. */ | |
| 1476 | |
| 1477 static struct builtin_info * | |
| 1478 alloc_builtin (data_reference_p dst_dr, data_reference_p src_dr, | |
| 1479 tree dst_base, tree src_base, tree size) | |
| 1480 { | |
| 1481 struct builtin_info *builtin = XNEW (struct builtin_info); | |
| 1482 builtin->dst_dr = dst_dr; | |
| 1483 builtin->src_dr = src_dr; | |
| 1484 builtin->dst_base = dst_base; | |
| 1485 builtin->src_base = src_base; | |
| 1486 builtin->size = size; | |
| 1487 return builtin; | |
| 1488 } | |
| 1489 | |
| 1490 /* Given data reference DR in loop nest LOOP, classify if it forms builtin | |
| 1491 memset call. */ | |
| 0 | 1492 |
| 1493 static void | |
| 111 | 1494 classify_builtin_st (loop_p loop, partition *partition, data_reference_p dr) |
| 0 | 1495 { |
| 111 | 1496 gimple *stmt = DR_STMT (dr); |
| 1497 tree base, size, rhs = gimple_assign_rhs1 (stmt); | |
| 1498 | |
| 1499 if (const_with_all_bytes_same (rhs) == -1 | |
| 1500 && (!INTEGRAL_TYPE_P (TREE_TYPE (rhs)) | |
| 1501 || (TYPE_MODE (TREE_TYPE (rhs)) | |
| 1502 != TYPE_MODE (unsigned_char_type_node)))) | |
| 1503 return; | |
| 1504 | |
| 1505 if (TREE_CODE (rhs) == SSA_NAME | |
| 1506 && !SSA_NAME_IS_DEFAULT_DEF (rhs) | |
| 1507 && flow_bb_inside_loop_p (loop, gimple_bb (SSA_NAME_DEF_STMT (rhs)))) | |
| 1508 return; | |
| 1509 | |
| 1510 if (!compute_access_range (loop, dr, &base, &size)) | |
| 1511 return; | |
| 1512 | |
| 1513 struct builtin_info *builtin; | |
| 1514 builtin = alloc_builtin (dr, NULL, base, NULL_TREE, size); | |
| 1515 builtin->dst_base_base = strip_offset (builtin->dst_base, | |
| 1516 &builtin->dst_base_offset); | |
| 1517 partition->builtin = builtin; | |
| 1518 partition->kind = PKIND_MEMSET; | |
| 0 | 1519 } |
| 1520 | |
| 111 | 1521 /* Given data references DST_DR and SRC_DR in loop nest LOOP and RDG, classify |
| 1522 if it forms builtin memcpy or memmove call. */ | |
| 0 | 1523 |
| 1524 static void | |
| 111 | 1525 classify_builtin_ldst (loop_p loop, struct graph *rdg, partition *partition, |
| 1526 data_reference_p dst_dr, data_reference_p src_dr) | |
| 0 | 1527 { |
| 111 | 1528 tree base, size, src_base, src_size; |
| 1529 auto_vec<tree> dst_steps, src_steps; | |
| 1530 | |
| 1531 /* Compute access range of both load and store. They much have the same | |
| 1532 access size. */ | |
| 1533 if (!compute_access_range (loop, dst_dr, &base, &size, &dst_steps) | |
| 1534 || !compute_access_range (loop, src_dr, &src_base, &src_size, &src_steps) | |
| 1535 || !operand_equal_p (size, src_size, 0)) | |
| 1536 return; | |
| 1537 | |
| 1538 /* Load and store in loop nest must access memory in the same way, i.e, | |
| 1539 their must have the same steps in each loop of the nest. */ | |
| 1540 if (dst_steps.length () != src_steps.length ()) | |
| 1541 return; | |
| 1542 for (unsigned i = 0; i < dst_steps.length (); ++i) | |
| 1543 if (!operand_equal_p (dst_steps[i], src_steps[i], 0)) | |
| 1544 return; | |
| 1545 | |
| 1546 /* Now check that if there is a dependence. */ | |
| 1547 ddr_p ddr = get_data_dependence (rdg, src_dr, dst_dr); | |
| 1548 | |
| 1549 /* Classify as memcpy if no dependence between load and store. */ | |
| 1550 if (DDR_ARE_DEPENDENT (ddr) == chrec_known) | |
| 1551 { | |
| 1552 partition->builtin = alloc_builtin (dst_dr, src_dr, base, src_base, size); | |
| 1553 partition->kind = PKIND_MEMCPY; | |
| 1554 return; | |
| 1555 } | |
| 1556 | |
| 1557 /* Can't do memmove in case of unknown dependence or dependence without | |
| 1558 classical distance vector. */ | |
| 1559 if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know | |
| 1560 || DDR_NUM_DIST_VECTS (ddr) == 0) | |
| 1561 return; | |
| 1562 | |
| 1563 unsigned i; | |
| 1564 lambda_vector dist_v; | |
| 1565 int num_lev = (DDR_LOOP_NEST (ddr)).length (); | |
| 1566 FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, dist_v) | |
| 0 | 1567 { |
| 111 | 1568 unsigned dep_lev = dependence_level (dist_v, num_lev); |
| 1569 /* Can't do memmove if load depends on store. */ | |
| 1570 if (dep_lev > 0 && dist_v[dep_lev - 1] > 0 && !DDR_REVERSED_P (ddr)) | |
| 1571 return; | |
| 1572 } | |
| 1573 | |
| 1574 partition->builtin = alloc_builtin (dst_dr, src_dr, base, src_base, size); | |
| 1575 partition->kind = PKIND_MEMMOVE; | |
| 1576 return; | |
| 1577 } | |
| 1578 | |
| 1579 /* Classifies the builtin kind we can generate for PARTITION of RDG and LOOP. | |
| 1580 For the moment we detect memset, memcpy and memmove patterns. Bitmap | |
| 1581 STMT_IN_ALL_PARTITIONS contains statements belonging to all partitions. */ | |
| 1582 | |
| 1583 static void | |
| 1584 classify_partition (loop_p loop, struct graph *rdg, partition *partition, | |
| 1585 bitmap stmt_in_all_partitions) | |
| 1586 { | |
| 1587 bitmap_iterator bi; | |
| 1588 unsigned i; | |
| 1589 data_reference_p single_ld = NULL, single_st = NULL; | |
| 1590 bool volatiles_p = false, has_reduction = false; | |
| 1591 | |
| 1592 EXECUTE_IF_SET_IN_BITMAP (partition->stmts, 0, i, bi) | |
| 1593 { | |
| 1594 gimple *stmt = RDG_STMT (rdg, i); | |
| 1595 | |
| 1596 if (gimple_has_volatile_ops (stmt)) | |
| 1597 volatiles_p = true; | |
| 1598 | |
| 1599 /* If the stmt is not included by all partitions and there is uses | |
| 1600 outside of the loop, then mark the partition as reduction. */ | |
| 1601 if (stmt_has_scalar_dependences_outside_loop (loop, stmt)) | |
| 0 | 1602 { |
| 111 | 1603 /* Due to limitation in the transform phase we have to fuse all |
| 1604 reduction partitions. As a result, this could cancel valid | |
| 1605 loop distribution especially for loop that induction variable | |
| 1606 is used outside of loop. To workaround this issue, we skip | |
| 1607 marking partition as reudction if the reduction stmt belongs | |
| 1608 to all partitions. In such case, reduction will be computed | |
| 1609 correctly no matter how partitions are fused/distributed. */ | |
| 1610 if (!bitmap_bit_p (stmt_in_all_partitions, i)) | |
| 1611 { | |
| 1612 partition->reduction_p = true; | |
| 1613 return; | |
| 1614 } | |
| 1615 has_reduction = true; | |
| 0 | 1616 } |
| 1617 } | |
| 1618 | |
| 111 | 1619 /* Perform general partition disqualification for builtins. */ |
| 1620 if (volatiles_p | |
| 1621 /* Simple workaround to prevent classifying the partition as builtin | |
| 1622 if it contains any use outside of loop. */ | |
| 1623 || has_reduction | |
| 1624 || !flag_tree_loop_distribute_patterns) | |
| 1625 return; | |
| 1626 | |
| 1627 /* Find single load/store data references for builtin partition. */ | |
| 1628 if (!find_single_drs (loop, rdg, partition, &single_st, &single_ld)) | |
| 1629 return; | |
| 1630 | |
| 1631 /* Classify the builtin kind. */ | |
| 1632 if (single_ld == NULL) | |
| 1633 classify_builtin_st (loop, partition, single_st); | |
| 1634 else | |
| 1635 classify_builtin_ldst (loop, rdg, partition, single_st, single_ld); | |
| 0 | 1636 } |
| 1637 | |
| 111 | 1638 /* Returns true when PARTITION1 and PARTITION2 access the same memory |
| 1639 object in RDG. */ | |
|
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1640 |
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1641 static bool |
| 111 | 1642 share_memory_accesses (struct graph *rdg, |
| 1643 partition *partition1, partition *partition2) | |
|
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1644 { |
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1645 unsigned i, j; |
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1646 bitmap_iterator bi, bj; |
| 111 | 1647 data_reference_p dr1, dr2; |
| 1648 | |
| 1649 /* First check whether in the intersection of the two partitions are | |
| 1650 any loads or stores. Common loads are the situation that happens | |
| 1651 most often. */ | |
| 1652 EXECUTE_IF_AND_IN_BITMAP (partition1->stmts, partition2->stmts, 0, i, bi) | |
|
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1653 if (RDG_MEM_WRITE_STMT (rdg, i) |
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1654 || RDG_MEM_READS_STMT (rdg, i)) |
| 111 | 1655 return true; |
| 1656 | |
| 1657 /* Then check whether the two partitions access the same memory object. */ | |
| 1658 EXECUTE_IF_SET_IN_BITMAP (partition1->datarefs, 0, i, bi) | |
| 1659 { | |
| 1660 dr1 = datarefs_vec[i]; | |
| 1661 | |
| 1662 if (!DR_BASE_ADDRESS (dr1) | |
| 1663 || !DR_OFFSET (dr1) || !DR_INIT (dr1) || !DR_STEP (dr1)) | |
| 1664 continue; | |
| 1665 | |
| 1666 EXECUTE_IF_SET_IN_BITMAP (partition2->datarefs, 0, j, bj) | |
| 1667 { | |
| 1668 dr2 = datarefs_vec[j]; | |
| 1669 | |
| 1670 if (!DR_BASE_ADDRESS (dr2) | |
| 1671 || !DR_OFFSET (dr2) || !DR_INIT (dr2) || !DR_STEP (dr2)) | |
| 1672 continue; | |
| 1673 | |
| 1674 if (operand_equal_p (DR_BASE_ADDRESS (dr1), DR_BASE_ADDRESS (dr2), 0) | |
| 1675 && operand_equal_p (DR_OFFSET (dr1), DR_OFFSET (dr2), 0) | |
| 1676 && operand_equal_p (DR_INIT (dr1), DR_INIT (dr2), 0) | |
| 1677 && operand_equal_p (DR_STEP (dr1), DR_STEP (dr2), 0)) | |
|
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1678 return true; |
| 111 | 1679 } |
|
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1680 } |
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1681 |
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1682 return false; |
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1683 } |
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1684 |
| 111 | 1685 /* For each seed statement in STARTING_STMTS, this function builds |
| 1686 partition for it by adding depended statements according to RDG. | |
| 1687 All partitions are recorded in PARTITIONS. */ | |
|
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1688 |
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1689 static void |
| 111 | 1690 rdg_build_partitions (struct graph *rdg, |
| 1691 vec<gimple *> starting_stmts, | |
| 1692 vec<partition *> *partitions) | |
|
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1693 { |
| 111 | 1694 auto_bitmap processed; |
| 0 | 1695 int i; |
| 111 | 1696 gimple *stmt; |
| 1697 | |
| 1698 FOR_EACH_VEC_ELT (starting_stmts, i, stmt) | |
| 0 | 1699 { |
| 111 | 1700 int v = rdg_vertex_for_stmt (rdg, stmt); |
| 1701 | |
| 1702 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 1703 fprintf (dump_file, | |
| 1704 "ldist asked to generate code for vertex %d\n", v); | |
| 1705 | |
| 1706 /* If the vertex is already contained in another partition so | |
| 1707 is the partition rooted at it. */ | |
| 0 | 1708 if (bitmap_bit_p (processed, v)) |
| 1709 continue; | |
|
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1710 |
| 111 | 1711 partition *partition = build_rdg_partition_for_vertex (rdg, v); |
| 1712 bitmap_ior_into (processed, partition->stmts); | |
| 1713 | |
| 1714 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 0 | 1715 { |
| 111 | 1716 fprintf (dump_file, "ldist creates useful %s partition:\n", |
| 1717 partition->type == PTYPE_PARALLEL ? "parallel" : "sequent"); | |
| 1718 bitmap_print (dump_file, partition->stmts, " ", "\n"); | |
| 0 | 1719 } |
| 111 | 1720 |
| 1721 partitions->safe_push (partition); | |
| 0 | 1722 } |
| 1723 | |
| 111 | 1724 /* All vertices should have been assigned to at least one partition now, |
| 1725 other than vertices belonging to dead code. */ | |
| 0 | 1726 } |
| 1727 | |
| 1728 /* Dump to FILE the PARTITIONS. */ | |
| 1729 | |
| 1730 static void | |
| 111 | 1731 dump_rdg_partitions (FILE *file, vec<partition *> partitions) |
| 0 | 1732 { |
| 1733 int i; | |
| 111 | 1734 partition *partition; |
| 1735 | |
| 1736 FOR_EACH_VEC_ELT (partitions, i, partition) | |
| 1737 debug_bitmap_file (file, partition->stmts); | |
| 0 | 1738 } |
| 1739 | |
| 1740 /* Debug PARTITIONS. */ | |
| 111 | 1741 extern void debug_rdg_partitions (vec<partition *> ); |
| 0 | 1742 |
|
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1743 DEBUG_FUNCTION void |
| 111 | 1744 debug_rdg_partitions (vec<partition *> partitions) |
| 0 | 1745 { |
| 1746 dump_rdg_partitions (stderr, partitions); | |
| 1747 } | |
| 1748 | |
| 1749 /* Returns the number of read and write operations in the RDG. */ | |
| 1750 | |
| 1751 static int | |
| 1752 number_of_rw_in_rdg (struct graph *rdg) | |
| 1753 { | |
| 1754 int i, res = 0; | |
| 1755 | |
| 1756 for (i = 0; i < rdg->n_vertices; i++) | |
| 1757 { | |
| 1758 if (RDG_MEM_WRITE_STMT (rdg, i)) | |
| 1759 ++res; | |
| 1760 | |
| 1761 if (RDG_MEM_READS_STMT (rdg, i)) | |
| 1762 ++res; | |
| 1763 } | |
| 1764 | |
| 1765 return res; | |
| 1766 } | |
| 1767 | |
| 1768 /* Returns the number of read and write operations in a PARTITION of | |
| 1769 the RDG. */ | |
| 1770 | |
| 1771 static int | |
| 111 | 1772 number_of_rw_in_partition (struct graph *rdg, partition *partition) |
| 0 | 1773 { |
| 1774 int res = 0; | |
| 1775 unsigned i; | |
| 1776 bitmap_iterator ii; | |
| 1777 | |
| 111 | 1778 EXECUTE_IF_SET_IN_BITMAP (partition->stmts, 0, i, ii) |
| 0 | 1779 { |
| 1780 if (RDG_MEM_WRITE_STMT (rdg, i)) | |
| 1781 ++res; | |
| 1782 | |
| 1783 if (RDG_MEM_READS_STMT (rdg, i)) | |
| 1784 ++res; | |
| 1785 } | |
| 1786 | |
| 1787 return res; | |
| 1788 } | |
| 1789 | |
| 1790 /* Returns true when one of the PARTITIONS contains all the read or | |
| 1791 write operations of RDG. */ | |
| 1792 | |
| 1793 static bool | |
| 111 | 1794 partition_contains_all_rw (struct graph *rdg, |
| 1795 vec<partition *> partitions) | |
| 0 | 1796 { |
| 1797 int i; | |
| 111 | 1798 partition *partition; |
| 0 | 1799 int nrw = number_of_rw_in_rdg (rdg); |
| 1800 | |
| 111 | 1801 FOR_EACH_VEC_ELT (partitions, i, partition) |
| 0 | 1802 if (nrw == number_of_rw_in_partition (rdg, partition)) |
| 1803 return true; | |
| 1804 | |
| 1805 return false; | |
| 1806 } | |
| 1807 | |
| 111 | 1808 /* Compute partition dependence created by the data references in DRS1 |
| 1809 and DRS2, modify and return DIR according to that. IF ALIAS_DDR is | |
| 1810 not NULL, we record dependence introduced by possible alias between | |
| 1811 two data references in ALIAS_DDRS; otherwise, we simply ignore such | |
| 1812 dependence as if it doesn't exist at all. */ | |
| 1813 | |
| 1814 static int | |
| 1815 pg_add_dependence_edges (struct graph *rdg, int dir, | |
| 1816 bitmap drs1, bitmap drs2, vec<ddr_p> *alias_ddrs) | |
| 1817 { | |
| 1818 unsigned i, j; | |
| 1819 bitmap_iterator bi, bj; | |
| 1820 data_reference_p dr1, dr2, saved_dr1; | |
| 1821 | |
| 1822 /* dependence direction - 0 is no dependence, -1 is back, | |
| 1823 1 is forth, 2 is both (we can stop then, merging will occur). */ | |
| 1824 EXECUTE_IF_SET_IN_BITMAP (drs1, 0, i, bi) | |
| 1825 { | |
| 1826 dr1 = datarefs_vec[i]; | |
| 1827 | |
| 1828 EXECUTE_IF_SET_IN_BITMAP (drs2, 0, j, bj) | |
| 1829 { | |
| 1830 int res, this_dir = 1; | |
| 1831 ddr_p ddr; | |
| 1832 | |
| 1833 dr2 = datarefs_vec[j]; | |
| 1834 | |
| 1835 /* Skip all <read, read> data dependence. */ | |
| 1836 if (DR_IS_READ (dr1) && DR_IS_READ (dr2)) | |
| 1837 continue; | |
| 1838 | |
| 1839 saved_dr1 = dr1; | |
| 1840 /* Re-shuffle data-refs to be in topological order. */ | |
| 1841 if (rdg_vertex_for_stmt (rdg, DR_STMT (dr1)) | |
| 1842 > rdg_vertex_for_stmt (rdg, DR_STMT (dr2))) | |
| 1843 { | |
| 1844 std::swap (dr1, dr2); | |
| 1845 this_dir = -this_dir; | |
| 1846 } | |
| 1847 ddr = get_data_dependence (rdg, dr1, dr2); | |
| 1848 if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) | |
| 1849 { | |
| 1850 this_dir = 0; | |
| 1851 res = data_ref_compare_tree (DR_BASE_ADDRESS (dr1), | |
| 1852 DR_BASE_ADDRESS (dr2)); | |
| 1853 /* Be conservative. If data references are not well analyzed, | |
| 1854 or the two data references have the same base address and | |
| 1855 offset, add dependence and consider it alias to each other. | |
| 1856 In other words, the dependence can not be resolved by | |
| 1857 runtime alias check. */ | |
| 1858 if (!DR_BASE_ADDRESS (dr1) || !DR_BASE_ADDRESS (dr2) | |
| 1859 || !DR_OFFSET (dr1) || !DR_OFFSET (dr2) | |
| 1860 || !DR_INIT (dr1) || !DR_INIT (dr2) | |
| 1861 || !DR_STEP (dr1) || !tree_fits_uhwi_p (DR_STEP (dr1)) | |
| 1862 || !DR_STEP (dr2) || !tree_fits_uhwi_p (DR_STEP (dr2)) | |
| 1863 || res == 0) | |
| 1864 this_dir = 2; | |
| 1865 /* Data dependence could be resolved by runtime alias check, | |
| 1866 record it in ALIAS_DDRS. */ | |
| 1867 else if (alias_ddrs != NULL) | |
| 1868 alias_ddrs->safe_push (ddr); | |
| 1869 /* Or simply ignore it. */ | |
| 1870 } | |
| 1871 else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) | |
| 1872 { | |
| 1873 if (DDR_REVERSED_P (ddr)) | |
| 1874 this_dir = -this_dir; | |
| 1875 | |
| 1876 /* Known dependences can still be unordered througout the | |
| 1877 iteration space, see gcc.dg/tree-ssa/ldist-16.c. */ | |
| 1878 if (DDR_NUM_DIST_VECTS (ddr) != 1) | |
| 1879 this_dir = 2; | |
| 1880 /* If the overlap is exact preserve stmt order. */ | |
| 1881 else if (lambda_vector_zerop (DDR_DIST_VECT (ddr, 0), 1)) | |
| 1882 ; | |
| 1883 /* Else as the distance vector is lexicographic positive swap | |
| 1884 the dependence direction. */ | |
| 1885 else | |
| 1886 this_dir = -this_dir; | |
| 1887 } | |
| 1888 else | |
| 1889 this_dir = 0; | |
| 1890 if (this_dir == 2) | |
| 1891 return 2; | |
| 1892 else if (dir == 0) | |
| 1893 dir = this_dir; | |
| 1894 else if (this_dir != 0 && dir != this_dir) | |
| 1895 return 2; | |
| 1896 /* Shuffle "back" dr1. */ | |
| 1897 dr1 = saved_dr1; | |
| 1898 } | |
| 1899 } | |
| 1900 return dir; | |
| 1901 } | |
| 1902 | |
| 1903 /* Compare postorder number of the partition graph vertices V1 and V2. */ | |
| 0 | 1904 |
| 1905 static int | |
| 111 | 1906 pgcmp (const void *v1_, const void *v2_) |
| 1907 { | |
| 1908 const vertex *v1 = (const vertex *)v1_; | |
| 1909 const vertex *v2 = (const vertex *)v2_; | |
| 1910 return v2->post - v1->post; | |
| 1911 } | |
| 1912 | |
| 1913 /* Data attached to vertices of partition dependence graph. */ | |
| 1914 struct pg_vdata | |
| 1915 { | |
| 1916 /* ID of the corresponding partition. */ | |
| 1917 int id; | |
| 1918 /* The partition. */ | |
| 1919 struct partition *partition; | |
| 1920 }; | |
| 1921 | |
| 1922 /* Data attached to edges of partition dependence graph. */ | |
| 1923 struct pg_edata | |
| 1924 { | |
| 1925 /* If the dependence edge can be resolved by runtime alias check, | |
| 1926 this vector contains data dependence relations for runtime alias | |
| 1927 check. On the other hand, if the dependence edge is introduced | |
| 1928 because of compilation time known data dependence, this vector | |
| 1929 contains nothing. */ | |
| 1930 vec<ddr_p> alias_ddrs; | |
| 1931 }; | |
| 1932 | |
| 1933 /* Callback data for traversing edges in graph. */ | |
| 1934 struct pg_edge_callback_data | |
| 0 | 1935 { |
| 111 | 1936 /* Bitmap contains strong connected components should be merged. */ |
| 1937 bitmap sccs_to_merge; | |
| 1938 /* Array constains component information for all vertices. */ | |
| 1939 int *vertices_component; | |
| 1940 /* Vector to record all data dependence relations which are needed | |
| 1941 to break strong connected components by runtime alias checks. */ | |
| 1942 vec<ddr_p> *alias_ddrs; | |
| 1943 }; | |
| 1944 | |
| 1945 /* Initialize vertice's data for partition dependence graph PG with | |
| 1946 PARTITIONS. */ | |
| 1947 | |
| 1948 static void | |
| 1949 init_partition_graph_vertices (struct graph *pg, | |
| 1950 vec<struct partition *> *partitions) | |
| 1951 { | |
| 1952 int i; | |
| 1953 partition *partition; | |
| 1954 struct pg_vdata *data; | |
| 1955 | |
| 1956 for (i = 0; partitions->iterate (i, &partition); ++i) | |
| 1957 { | |
| 1958 data = new pg_vdata; | |
| 1959 pg->vertices[i].data = data; | |
| 1960 data->id = i; | |
| 1961 data->partition = partition; | |
| 1962 } | |
| 1963 } | |
| 1964 | |
| 1965 /* Add edge <I, J> to partition dependence graph PG. Attach vector of data | |
| 1966 dependence relations to the EDGE if DDRS isn't NULL. */ | |
| 1967 | |
| 1968 static void | |
| 1969 add_partition_graph_edge (struct graph *pg, int i, int j, vec<ddr_p> *ddrs) | |
| 1970 { | |
| 1971 struct graph_edge *e = add_edge (pg, i, j); | |
| 1972 | |
| 1973 /* If the edge is attached with data dependence relations, it means this | |
| 1974 dependence edge can be resolved by runtime alias checks. */ | |
| 1975 if (ddrs != NULL) | |
| 0 | 1976 { |
| 111 | 1977 struct pg_edata *data = new pg_edata; |
| 1978 | |
| 1979 gcc_assert (ddrs->length () > 0); | |
| 1980 e->data = data; | |
| 1981 data->alias_ddrs = vNULL; | |
| 1982 data->alias_ddrs.safe_splice (*ddrs); | |
| 1983 } | |
| 1984 } | |
| 1985 | |
| 1986 /* Callback function for graph travesal algorithm. It returns true | |
| 1987 if edge E should skipped when traversing the graph. */ | |
| 1988 | |
| 1989 static bool | |
| 1990 pg_skip_alias_edge (struct graph_edge *e) | |
| 1991 { | |
| 1992 struct pg_edata *data = (struct pg_edata *)e->data; | |
| 1993 return (data != NULL && data->alias_ddrs.length () > 0); | |
| 1994 } | |
| 1995 | |
| 1996 /* Callback function freeing data attached to edge E of graph. */ | |
| 1997 | |
| 1998 static void | |
| 1999 free_partition_graph_edata_cb (struct graph *, struct graph_edge *e, void *) | |
| 2000 { | |
| 2001 if (e->data != NULL) | |
| 2002 { | |
| 2003 struct pg_edata *data = (struct pg_edata *)e->data; | |
| 2004 data->alias_ddrs.release (); | |
| 2005 delete data; | |
| 2006 } | |
| 2007 } | |
| 2008 | |
| 2009 /* Free data attached to vertice of partition dependence graph PG. */ | |
| 2010 | |
| 2011 static void | |
| 2012 free_partition_graph_vdata (struct graph *pg) | |
| 2013 { | |
| 2014 int i; | |
| 2015 struct pg_vdata *data; | |
| 2016 | |
| 2017 for (i = 0; i < pg->n_vertices; ++i) | |
| 2018 { | |
| 2019 data = (struct pg_vdata *)pg->vertices[i].data; | |
| 2020 delete data; | |
| 2021 } | |
| 2022 } | |
| 2023 | |
| 2024 /* Build and return partition dependence graph for PARTITIONS. RDG is | |
| 2025 reduced dependence graph for the loop to be distributed. If IGNORE_ALIAS_P | |
| 2026 is true, data dependence caused by possible alias between references | |
| 2027 is ignored, as if it doesn't exist at all; otherwise all depdendences | |
| 2028 are considered. */ | |
| 2029 | |
| 2030 static struct graph * | |
| 2031 build_partition_graph (struct graph *rdg, | |
| 2032 vec<struct partition *> *partitions, | |
| 2033 bool ignore_alias_p) | |
| 2034 { | |
| 2035 int i, j; | |
| 2036 struct partition *partition1, *partition2; | |
| 2037 graph *pg = new_graph (partitions->length ()); | |
| 2038 auto_vec<ddr_p> alias_ddrs, *alias_ddrs_p; | |
| 2039 | |
| 2040 alias_ddrs_p = ignore_alias_p ? NULL : &alias_ddrs; | |
| 2041 | |
| 2042 init_partition_graph_vertices (pg, partitions); | |
| 2043 | |
| 2044 for (i = 0; partitions->iterate (i, &partition1); ++i) | |
| 2045 { | |
| 2046 for (j = i + 1; partitions->iterate (j, &partition2); ++j) | |
| 0 | 2047 { |
| 111 | 2048 /* dependence direction - 0 is no dependence, -1 is back, |
| 2049 1 is forth, 2 is both (we can stop then, merging will occur). */ | |
| 2050 int dir = 0; | |
| 2051 | |
| 2052 /* If the first partition has reduction, add back edge; if the | |
| 2053 second partition has reduction, add forth edge. This makes | |
| 2054 sure that reduction partition will be sorted as the last one. */ | |
| 2055 if (partition_reduction_p (partition1)) | |
| 2056 dir = -1; | |
| 2057 else if (partition_reduction_p (partition2)) | |
| 2058 dir = 1; | |
| 2059 | |
| 2060 /* Cleanup the temporary vector. */ | |
| 2061 alias_ddrs.truncate (0); | |
| 2062 | |
| 2063 dir = pg_add_dependence_edges (rdg, dir, partition1->datarefs, | |
| 2064 partition2->datarefs, alias_ddrs_p); | |
| 2065 | |
| 2066 /* Add edge to partition graph if there exists dependence. There | |
| 2067 are two types of edges. One type edge is caused by compilation | |
| 2068 time known dependence, this type can not be resolved by runtime | |
| 2069 alias check. The other type can be resolved by runtime alias | |
| 2070 check. */ | |
| 2071 if (dir == 1 || dir == 2 | |
| 2072 || alias_ddrs.length () > 0) | |
| 2073 { | |
| 2074 /* Attach data dependence relations to edge that can be resolved | |
| 2075 by runtime alias check. */ | |
| 2076 bool alias_edge_p = (dir != 1 && dir != 2); | |
| 2077 add_partition_graph_edge (pg, i, j, | |
| 2078 (alias_edge_p) ? &alias_ddrs : NULL); | |
| 2079 } | |
| 2080 if (dir == -1 || dir == 2 | |
| 2081 || alias_ddrs.length () > 0) | |
| 2082 { | |
| 2083 /* Attach data dependence relations to edge that can be resolved | |
| 2084 by runtime alias check. */ | |
| 2085 bool alias_edge_p = (dir != -1 && dir != 2); | |
| 2086 add_partition_graph_edge (pg, j, i, | |
| 2087 (alias_edge_p) ? &alias_ddrs : NULL); | |
| 2088 } | |
| 0 | 2089 } |
| 2090 } | |
| 111 | 2091 return pg; |
| 2092 } | |
| 2093 | |
| 2094 /* Sort partitions in PG in descending post order and store them in | |
| 2095 PARTITIONS. */ | |
| 2096 | |
| 2097 static void | |
| 2098 sort_partitions_by_post_order (struct graph *pg, | |
| 2099 vec<struct partition *> *partitions) | |
| 2100 { | |
| 2101 int i; | |
| 2102 struct pg_vdata *data; | |
| 2103 | |
| 2104 /* Now order the remaining nodes in descending postorder. */ | |
| 2105 qsort (pg->vertices, pg->n_vertices, sizeof (vertex), pgcmp); | |
| 2106 partitions->truncate (0); | |
| 2107 for (i = 0; i < pg->n_vertices; ++i) | |
| 2108 { | |
| 2109 data = (struct pg_vdata *)pg->vertices[i].data; | |
| 2110 if (data->partition) | |
| 2111 partitions->safe_push (data->partition); | |
| 2112 } | |
| 2113 } | |
| 2114 | |
| 2115 /* Given reduced dependence graph RDG merge strong connected components | |
| 2116 of PARTITIONS. If IGNORE_ALIAS_P is true, data dependence caused by | |
| 2117 possible alias between references is ignored, as if it doesn't exist | |
| 2118 at all; otherwise all depdendences are considered. */ | |
| 2119 | |
| 2120 static void | |
| 2121 merge_dep_scc_partitions (struct graph *rdg, | |
| 2122 vec<struct partition *> *partitions, | |
| 2123 bool ignore_alias_p) | |
| 2124 { | |
| 2125 struct partition *partition1, *partition2; | |
| 2126 struct pg_vdata *data; | |
| 2127 graph *pg = build_partition_graph (rdg, partitions, ignore_alias_p); | |
| 2128 int i, j, num_sccs = graphds_scc (pg, NULL); | |
| 2129 | |
| 2130 /* Strong connected compoenent means dependence cycle, we cannot distribute | |
| 2131 them. So fuse them together. */ | |
| 2132 if ((unsigned) num_sccs < partitions->length ()) | |
| 2133 { | |
| 2134 for (i = 0; i < num_sccs; ++i) | |
| 2135 { | |
| 2136 for (j = 0; partitions->iterate (j, &partition1); ++j) | |
| 2137 if (pg->vertices[j].component == i) | |
| 2138 break; | |
| 2139 for (j = j + 1; partitions->iterate (j, &partition2); ++j) | |
| 2140 if (pg->vertices[j].component == i) | |
| 2141 { | |
| 2142 partition_merge_into (NULL, partition1, | |
| 2143 partition2, FUSE_SAME_SCC); | |
| 2144 partition1->type = PTYPE_SEQUENTIAL; | |
| 2145 (*partitions)[j] = NULL; | |
| 2146 partition_free (partition2); | |
| 2147 data = (struct pg_vdata *)pg->vertices[j].data; | |
| 2148 data->partition = NULL; | |
| 2149 } | |
| 2150 } | |
| 2151 } | |
| 2152 | |
| 2153 sort_partitions_by_post_order (pg, partitions); | |
| 2154 gcc_assert (partitions->length () == (unsigned)num_sccs); | |
| 2155 free_partition_graph_vdata (pg); | |
| 2156 free_graph (pg); | |
| 2157 } | |
| 2158 | |
| 2159 /* Callback function for traversing edge E in graph G. DATA is private | |
| 2160 callback data. */ | |
| 2161 | |
| 2162 static void | |
| 2163 pg_collect_alias_ddrs (struct graph *g, struct graph_edge *e, void *data) | |
| 2164 { | |
| 2165 int i, j, component; | |
| 2166 struct pg_edge_callback_data *cbdata; | |
| 2167 struct pg_edata *edata = (struct pg_edata *) e->data; | |
| 2168 | |
| 2169 /* If the edge doesn't have attached data dependence, it represents | |
| 2170 compilation time known dependences. This type dependence cannot | |
| 2171 be resolved by runtime alias check. */ | |
| 2172 if (edata == NULL || edata->alias_ddrs.length () == 0) | |
| 2173 return; | |
| 2174 | |
| 2175 cbdata = (struct pg_edge_callback_data *) data; | |
| 2176 i = e->src; | |
| 2177 j = e->dest; | |
| 2178 component = cbdata->vertices_component[i]; | |
| 2179 /* Vertices are topologically sorted according to compilation time | |
| 2180 known dependences, so we can break strong connected components | |
| 2181 by removing edges of the opposite direction, i.e, edges pointing | |
| 2182 from vertice with smaller post number to vertice with bigger post | |
| 2183 number. */ | |
| 2184 if (g->vertices[i].post < g->vertices[j].post | |
| 2185 /* We only need to remove edges connecting vertices in the same | |
| 2186 strong connected component to break it. */ | |
| 2187 && component == cbdata->vertices_component[j] | |
| 2188 /* Check if we want to break the strong connected component or not. */ | |
| 2189 && !bitmap_bit_p (cbdata->sccs_to_merge, component)) | |
| 2190 cbdata->alias_ddrs->safe_splice (edata->alias_ddrs); | |
| 2191 } | |
| 2192 | |
| 2193 /* This is the main function breaking strong conected components in | |
| 2194 PARTITIONS giving reduced depdendence graph RDG. Store data dependence | |
| 2195 relations for runtime alias check in ALIAS_DDRS. */ | |
| 2196 | |
| 2197 static void | |
| 2198 break_alias_scc_partitions (struct graph *rdg, | |
| 2199 vec<struct partition *> *partitions, | |
| 2200 vec<ddr_p> *alias_ddrs) | |
| 2201 { | |
| 2202 int i, j, k, num_sccs, num_sccs_no_alias; | |
| 2203 /* Build partition dependence graph. */ | |
| 2204 graph *pg = build_partition_graph (rdg, partitions, false); | |
| 2205 | |
| 2206 alias_ddrs->truncate (0); | |
| 2207 /* Find strong connected components in the graph, with all dependence edges | |
| 2208 considered. */ | |
| 2209 num_sccs = graphds_scc (pg, NULL); | |
| 2210 /* All SCCs now can be broken by runtime alias checks because SCCs caused by | |
| 2211 compilation time known dependences are merged before this function. */ | |
| 2212 if ((unsigned) num_sccs < partitions->length ()) | |
| 2213 { | |
| 2214 struct pg_edge_callback_data cbdata; | |
| 2215 auto_bitmap sccs_to_merge; | |
| 2216 auto_vec<enum partition_type> scc_types; | |
| 2217 struct partition *partition, *first; | |
| 2218 | |
| 2219 /* If all partitions in a SCC have the same type, we can simply merge the | |
| 2220 SCC. This loop finds out such SCCS and record them in bitmap. */ | |
| 2221 bitmap_set_range (sccs_to_merge, 0, (unsigned) num_sccs); | |
| 2222 for (i = 0; i < num_sccs; ++i) | |
| 2223 { | |
| 2224 for (j = 0; partitions->iterate (j, &first); ++j) | |
| 2225 if (pg->vertices[j].component == i) | |
| 2226 break; | |
| 2227 for (++j; partitions->iterate (j, &partition); ++j) | |
| 2228 { | |
| 2229 if (pg->vertices[j].component != i) | |
| 2230 continue; | |
| 2231 | |
| 2232 /* Note we Merge partitions of parallel type on purpose, though | |
| 2233 the result partition is sequential. The reason is vectorizer | |
| 2234 can do more accurate runtime alias check in this case. Also | |
| 2235 it results in more conservative distribution. */ | |
| 2236 if (first->type != partition->type) | |
| 2237 { | |
| 2238 bitmap_clear_bit (sccs_to_merge, i); | |
| 2239 break; | |
| 2240 } | |
| 2241 } | |
| 2242 } | |
| 2243 | |
| 2244 /* Initialize callback data for traversing. */ | |
| 2245 cbdata.sccs_to_merge = sccs_to_merge; | |
| 2246 cbdata.alias_ddrs = alias_ddrs; | |
| 2247 cbdata.vertices_component = XNEWVEC (int, pg->n_vertices); | |
| 2248 /* Record the component information which will be corrupted by next | |
| 2249 graph scc finding call. */ | |
| 2250 for (i = 0; i < pg->n_vertices; ++i) | |
| 2251 cbdata.vertices_component[i] = pg->vertices[i].component; | |
| 2252 | |
| 2253 /* Collect data dependences for runtime alias checks to break SCCs. */ | |
| 2254 if (bitmap_count_bits (sccs_to_merge) != (unsigned) num_sccs) | |
| 2255 { | |
| 2256 /* Run SCC finding algorithm again, with alias dependence edges | |
| 2257 skipped. This is to topologically sort partitions according to | |
| 2258 compilation time known dependence. Note the topological order | |
| 2259 is stored in the form of pg's post order number. */ | |
| 2260 num_sccs_no_alias = graphds_scc (pg, NULL, pg_skip_alias_edge); | |
| 2261 gcc_assert (partitions->length () == (unsigned) num_sccs_no_alias); | |
| 2262 /* With topological order, we can construct two subgraphs L and R. | |
| 2263 L contains edge <x, y> where x < y in terms of post order, while | |
| 2264 R contains edge <x, y> where x > y. Edges for compilation time | |
| 2265 known dependence all fall in R, so we break SCCs by removing all | |
| 2266 (alias) edges of in subgraph L. */ | |
| 2267 for_each_edge (pg, pg_collect_alias_ddrs, &cbdata); | |
| 2268 } | |
| 2269 | |
| 2270 /* For SCC that doesn't need to be broken, merge it. */ | |
| 2271 for (i = 0; i < num_sccs; ++i) | |
| 2272 { | |
| 2273 if (!bitmap_bit_p (sccs_to_merge, i)) | |
| 2274 continue; | |
| 2275 | |
| 2276 for (j = 0; partitions->iterate (j, &first); ++j) | |
| 2277 if (cbdata.vertices_component[j] == i) | |
| 2278 break; | |
| 2279 for (k = j + 1; partitions->iterate (k, &partition); ++k) | |
| 2280 { | |
| 2281 struct pg_vdata *data; | |
| 2282 | |
| 2283 if (cbdata.vertices_component[k] != i) | |
| 2284 continue; | |
| 2285 | |
| 2286 /* Update postorder number so that merged reduction partition is | |
| 2287 sorted after other partitions. */ | |
| 2288 if (!partition_reduction_p (first) | |
| 2289 && partition_reduction_p (partition)) | |
| 2290 { | |
| 2291 gcc_assert (pg->vertices[k].post < pg->vertices[j].post); | |
| 2292 pg->vertices[j].post = pg->vertices[k].post; | |
| 2293 } | |
| 2294 partition_merge_into (NULL, first, partition, FUSE_SAME_SCC); | |
| 2295 (*partitions)[k] = NULL; | |
| 2296 partition_free (partition); | |
| 2297 data = (struct pg_vdata *)pg->vertices[k].data; | |
| 2298 gcc_assert (data->id == k); | |
| 2299 data->partition = NULL; | |
| 2300 /* The result partition of merged SCC must be sequential. */ | |
| 2301 first->type = PTYPE_SEQUENTIAL; | |
| 2302 } | |
| 2303 } | |
| 2304 } | |
| 2305 | |
| 2306 sort_partitions_by_post_order (pg, partitions); | |
| 2307 free_partition_graph_vdata (pg); | |
| 2308 for_each_edge (pg, free_partition_graph_edata_cb, NULL); | |
| 2309 free_graph (pg); | |
| 0 | 2310 |
| 2311 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 111 | 2312 { |
| 2313 fprintf (dump_file, "Possible alias data dependence to break:\n"); | |
| 2314 dump_data_dependence_relations (dump_file, *alias_ddrs); | |
| 2315 } | |
| 2316 } | |
| 2317 | |
| 2318 /* Compute and return an expression whose value is the segment length which | |
| 2319 will be accessed by DR in NITERS iterations. */ | |
| 2320 | |
| 2321 static tree | |
| 2322 data_ref_segment_size (struct data_reference *dr, tree niters) | |
| 2323 { | |
| 2324 tree segment_length; | |
| 2325 | |
| 2326 if (integer_zerop (DR_STEP (dr))) | |
| 2327 segment_length = TYPE_SIZE_UNIT (TREE_TYPE (DR_REF (dr))); | |
| 2328 else | |
| 2329 segment_length = size_binop (MULT_EXPR, | |
| 2330 fold_convert (sizetype, DR_STEP (dr)), | |
| 2331 fold_convert (sizetype, niters)); | |
| 2332 | |
| 2333 return segment_length; | |
| 2334 } | |
| 2335 | |
| 2336 /* Return true if LOOP's latch is dominated by statement for data reference | |
| 2337 DR. */ | |
| 2338 | |
| 2339 static inline bool | |
| 2340 latch_dominated_by_data_ref (struct loop *loop, data_reference *dr) | |
| 2341 { | |
| 2342 return dominated_by_p (CDI_DOMINATORS, single_exit (loop)->src, | |
| 2343 gimple_bb (DR_STMT (dr))); | |
| 2344 } | |
| 2345 | |
| 2346 /* Compute alias check pairs and store them in COMP_ALIAS_PAIRS for LOOP's | |
| 2347 data dependence relations ALIAS_DDRS. */ | |
| 2348 | |
| 2349 static void | |
| 2350 compute_alias_check_pairs (struct loop *loop, vec<ddr_p> *alias_ddrs, | |
| 2351 vec<dr_with_seg_len_pair_t> *comp_alias_pairs) | |
| 2352 { | |
| 2353 unsigned int i; | |
| 2354 unsigned HOST_WIDE_INT factor = 1; | |
| 2355 tree niters_plus_one, niters = number_of_latch_executions (loop); | |
| 2356 | |
| 2357 gcc_assert (niters != NULL_TREE && niters != chrec_dont_know); | |
| 2358 niters = fold_convert (sizetype, niters); | |
| 2359 niters_plus_one = size_binop (PLUS_EXPR, niters, size_one_node); | |
| 2360 | |
| 2361 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2362 fprintf (dump_file, "Creating alias check pairs:\n"); | |
| 2363 | |
| 2364 /* Iterate all data dependence relations and compute alias check pairs. */ | |
| 2365 for (i = 0; i < alias_ddrs->length (); i++) | |
| 2366 { | |
| 2367 ddr_p ddr = (*alias_ddrs)[i]; | |
| 2368 struct data_reference *dr_a = DDR_A (ddr); | |
| 2369 struct data_reference *dr_b = DDR_B (ddr); | |
| 2370 tree seg_length_a, seg_length_b; | |
| 2371 int comp_res = data_ref_compare_tree (DR_BASE_ADDRESS (dr_a), | |
| 2372 DR_BASE_ADDRESS (dr_b)); | |
| 2373 | |
| 2374 if (comp_res == 0) | |
| 2375 comp_res = data_ref_compare_tree (DR_OFFSET (dr_a), DR_OFFSET (dr_b)); | |
| 2376 gcc_assert (comp_res != 0); | |
| 2377 | |
| 2378 if (latch_dominated_by_data_ref (loop, dr_a)) | |
| 2379 seg_length_a = data_ref_segment_size (dr_a, niters_plus_one); | |
| 2380 else | |
| 2381 seg_length_a = data_ref_segment_size (dr_a, niters); | |
| 2382 | |
| 2383 if (latch_dominated_by_data_ref (loop, dr_b)) | |
| 2384 seg_length_b = data_ref_segment_size (dr_b, niters_plus_one); | |
| 2385 else | |
| 2386 seg_length_b = data_ref_segment_size (dr_b, niters); | |
| 2387 | |
| 2388 dr_with_seg_len_pair_t dr_with_seg_len_pair | |
| 2389 (dr_with_seg_len (dr_a, seg_length_a), | |
| 2390 dr_with_seg_len (dr_b, seg_length_b)); | |
| 2391 | |
| 2392 /* Canonicalize pairs by sorting the two DR members. */ | |
| 2393 if (comp_res > 0) | |
| 2394 std::swap (dr_with_seg_len_pair.first, dr_with_seg_len_pair.second); | |
| 2395 | |
| 2396 comp_alias_pairs->safe_push (dr_with_seg_len_pair); | |
| 2397 } | |
| 2398 | |
| 2399 if (tree_fits_uhwi_p (niters)) | |
| 2400 factor = tree_to_uhwi (niters); | |
| 2401 | |
| 2402 /* Prune alias check pairs. */ | |
| 2403 prune_runtime_alias_test_list (comp_alias_pairs, factor); | |
| 2404 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2405 fprintf (dump_file, | |
| 2406 "Improved number of alias checks from %d to %d\n", | |
| 2407 alias_ddrs->length (), comp_alias_pairs->length ()); | |
| 2408 } | |
| 2409 | |
| 2410 /* Given data dependence relations in ALIAS_DDRS, generate runtime alias | |
| 2411 checks and version LOOP under condition of these runtime alias checks. */ | |
| 2412 | |
| 2413 static void | |
| 2414 version_loop_by_alias_check (struct loop *loop, vec<ddr_p> *alias_ddrs) | |
| 2415 { | |
| 2416 profile_probability prob; | |
| 2417 basic_block cond_bb; | |
| 2418 struct loop *nloop; | |
| 2419 tree lhs, arg0, cond_expr = NULL_TREE; | |
| 2420 gimple_seq cond_stmts = NULL; | |
| 2421 gimple *call_stmt = NULL; | |
| 2422 auto_vec<dr_with_seg_len_pair_t> comp_alias_pairs; | |
| 2423 | |
| 2424 /* Generate code for runtime alias checks if necessary. */ | |
| 2425 gcc_assert (alias_ddrs->length () > 0); | |
| 2426 | |
| 2427 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2428 fprintf (dump_file, | |
| 2429 "Version loop <%d> with runtime alias check\n", loop->num); | |
| 2430 | |
| 2431 compute_alias_check_pairs (loop, alias_ddrs, &comp_alias_pairs); | |
| 2432 create_runtime_alias_checks (loop, &comp_alias_pairs, &cond_expr); | |
| 2433 cond_expr = force_gimple_operand_1 (cond_expr, &cond_stmts, | |
| 2434 is_gimple_val, NULL_TREE); | |
| 2435 | |
| 2436 /* Depend on vectorizer to fold IFN_LOOP_DIST_ALIAS. */ | |
| 2437 if (flag_tree_loop_vectorize) | |
| 2438 { | |
| 2439 /* Generate internal function call for loop distribution alias check. */ | |
| 2440 call_stmt = gimple_build_call_internal (IFN_LOOP_DIST_ALIAS, | |
| 2441 2, NULL_TREE, cond_expr); | |
| 2442 lhs = make_ssa_name (boolean_type_node); | |
| 2443 gimple_call_set_lhs (call_stmt, lhs); | |
| 2444 } | |
| 2445 else | |
| 2446 lhs = cond_expr; | |
| 2447 | |
| 2448 prob = profile_probability::guessed_always ().apply_scale (9, 10); | |
| 2449 initialize_original_copy_tables (); | |
| 2450 nloop = loop_version (loop, lhs, &cond_bb, prob, prob.invert (), | |
| 2451 prob, prob.invert (), true); | |
| 2452 free_original_copy_tables (); | |
| 2453 /* Record the original loop number in newly generated loops. In case of | |
| 2454 distribution, the original loop will be distributed and the new loop | |
| 2455 is kept. */ | |
| 2456 loop->orig_loop_num = nloop->num; | |
| 2457 nloop->orig_loop_num = nloop->num; | |
| 2458 nloop->dont_vectorize = true; | |
| 2459 nloop->force_vectorize = false; | |
| 2460 | |
| 2461 if (call_stmt) | |
| 2462 { | |
| 2463 /* Record new loop's num in IFN_LOOP_DIST_ALIAS because the original | |
| 2464 loop could be destroyed. */ | |
| 2465 arg0 = build_int_cst (integer_type_node, loop->orig_loop_num); | |
| 2466 gimple_call_set_arg (call_stmt, 0, arg0); | |
| 2467 gimple_seq_add_stmt_without_update (&cond_stmts, call_stmt); | |
| 2468 } | |
| 2469 | |
| 2470 if (cond_stmts) | |
| 2471 { | |
| 2472 gimple_stmt_iterator cond_gsi = gsi_last_bb (cond_bb); | |
| 2473 gsi_insert_seq_before (&cond_gsi, cond_stmts, GSI_SAME_STMT); | |
| 2474 } | |
| 2475 update_ssa (TODO_update_ssa); | |
| 0 | 2476 } |
| 2477 | |
| 111 | 2478 /* Return true if loop versioning is needed to distrubute PARTITIONS. |
| 2479 ALIAS_DDRS are data dependence relations for runtime alias check. */ | |
| 2480 | |
| 2481 static inline bool | |
| 2482 version_for_distribution_p (vec<struct partition *> *partitions, | |
| 2483 vec<ddr_p> *alias_ddrs) | |
| 2484 { | |
| 2485 /* No need to version loop if we have only one partition. */ | |
| 2486 if (partitions->length () == 1) | |
| 2487 return false; | |
| 2488 | |
| 2489 /* Need to version loop if runtime alias check is necessary. */ | |
| 2490 return (alias_ddrs->length () > 0); | |
| 2491 } | |
| 2492 | |
| 2493 /* Compare base offset of builtin mem* partitions P1 and P2. */ | |
| 2494 | |
| 2495 static bool | |
| 2496 offset_cmp (struct partition *p1, struct partition *p2) | |
| 2497 { | |
| 2498 gcc_assert (p1 != NULL && p1->builtin != NULL); | |
| 2499 gcc_assert (p2 != NULL && p2->builtin != NULL); | |
| 2500 return p1->builtin->dst_base_offset < p2->builtin->dst_base_offset; | |
| 2501 } | |
| 2502 | |
| 2503 /* Fuse adjacent memset builtin PARTITIONS if possible. This is a special | |
| 2504 case optimization transforming below code: | |
| 2505 | |
| 2506 __builtin_memset (&obj, 0, 100); | |
| 2507 _1 = &obj + 100; | |
| 2508 __builtin_memset (_1, 0, 200); | |
| 2509 _2 = &obj + 300; | |
| 2510 __builtin_memset (_2, 0, 100); | |
| 2511 | |
| 2512 into: | |
| 2513 | |
| 2514 __builtin_memset (&obj, 0, 400); | |
| 2515 | |
| 2516 Note we don't have dependence information between different partitions | |
| 2517 at this point, as a result, we can't handle nonadjacent memset builtin | |
| 2518 partitions since dependence might be broken. */ | |
| 2519 | |
| 2520 static void | |
| 2521 fuse_memset_builtins (vec<struct partition *> *partitions) | |
| 2522 { | |
| 2523 unsigned i, j; | |
| 2524 struct partition *part1, *part2; | |
| 2525 | |
| 2526 for (i = 0; partitions->iterate (i, &part1);) | |
| 2527 { | |
| 2528 if (part1->kind != PKIND_MEMSET) | |
| 2529 { | |
| 2530 i++; | |
| 2531 continue; | |
| 2532 } | |
| 2533 | |
| 2534 /* Find sub-array of memset builtins of the same base. Index range | |
| 2535 of the sub-array is [i, j) with "j > i". */ | |
| 2536 for (j = i + 1; partitions->iterate (j, &part2); ++j) | |
| 2537 { | |
| 2538 if (part2->kind != PKIND_MEMSET | |
| 2539 || !operand_equal_p (part1->builtin->dst_base_base, | |
| 2540 part2->builtin->dst_base_base, 0)) | |
| 2541 break; | |
| 2542 } | |
| 2543 | |
| 2544 /* Stable sort is required in order to avoid breaking dependence. */ | |
| 2545 std::stable_sort (&(*partitions)[i], | |
| 2546 &(*partitions)[i] + j - i, offset_cmp); | |
| 2547 /* Continue with next partition. */ | |
| 2548 i = j; | |
| 2549 } | |
| 2550 | |
| 2551 /* Merge all consecutive memset builtin partitions. */ | |
| 2552 for (i = 0; i < partitions->length () - 1;) | |
| 2553 { | |
| 2554 part1 = (*partitions)[i]; | |
| 2555 if (part1->kind != PKIND_MEMSET) | |
| 2556 { | |
| 2557 i++; | |
| 2558 continue; | |
| 2559 } | |
| 2560 | |
| 2561 part2 = (*partitions)[i + 1]; | |
| 2562 /* Only merge memset partitions of the same base and with constant | |
| 2563 access sizes. */ | |
| 2564 if (part2->kind != PKIND_MEMSET | |
| 2565 || TREE_CODE (part1->builtin->size) != INTEGER_CST | |
| 2566 || TREE_CODE (part2->builtin->size) != INTEGER_CST | |
| 2567 || !operand_equal_p (part1->builtin->dst_base_base, | |
| 2568 part2->builtin->dst_base_base, 0)) | |
| 2569 { | |
| 2570 i++; | |
| 2571 continue; | |
| 2572 } | |
| 2573 tree rhs1 = gimple_assign_rhs1 (DR_STMT (part1->builtin->dst_dr)); | |
| 2574 tree rhs2 = gimple_assign_rhs1 (DR_STMT (part2->builtin->dst_dr)); | |
| 2575 int bytev1 = const_with_all_bytes_same (rhs1); | |
| 2576 int bytev2 = const_with_all_bytes_same (rhs2); | |
| 2577 /* Only merge memset partitions of the same value. */ | |
| 2578 if (bytev1 != bytev2 || bytev1 == -1) | |
| 2579 { | |
| 2580 i++; | |
| 2581 continue; | |
| 2582 } | |
| 2583 wide_int end1 = wi::add (part1->builtin->dst_base_offset, | |
| 2584 wi::to_wide (part1->builtin->size)); | |
| 2585 /* Only merge adjacent memset partitions. */ | |
| 2586 if (wi::ne_p (end1, part2->builtin->dst_base_offset)) | |
| 2587 { | |
| 2588 i++; | |
| 2589 continue; | |
| 2590 } | |
| 2591 /* Merge partitions[i] and partitions[i+1]. */ | |
| 2592 part1->builtin->size = fold_build2 (PLUS_EXPR, sizetype, | |
| 2593 part1->builtin->size, | |
| 2594 part2->builtin->size); | |
| 2595 partition_free (part2); | |
| 2596 partitions->ordered_remove (i + 1); | |
| 2597 } | |
| 2598 } | |
| 2599 | |
| 2600 /* Fuse PARTITIONS of LOOP if necessary before finalizing distribution. | |
| 2601 ALIAS_DDRS contains ddrs which need runtime alias check. */ | |
| 2602 | |
| 2603 static void | |
| 2604 finalize_partitions (struct loop *loop, vec<struct partition *> *partitions, | |
| 2605 vec<ddr_p> *alias_ddrs) | |
| 2606 { | |
| 2607 unsigned i; | |
| 2608 struct partition *partition, *a; | |
| 2609 | |
| 2610 if (partitions->length () == 1 | |
| 2611 || alias_ddrs->length () > 0) | |
| 2612 return; | |
| 2613 | |
| 2614 unsigned num_builtin = 0, num_normal = 0; | |
| 2615 bool same_type_p = true; | |
| 2616 enum partition_type type = ((*partitions)[0])->type; | |
| 2617 for (i = 0; partitions->iterate (i, &partition); ++i) | |
| 2618 { | |
| 2619 same_type_p &= (type == partition->type); | |
| 2620 if (partition->kind != PKIND_NORMAL) | |
| 2621 num_builtin++; | |
| 2622 else | |
| 2623 num_normal++; | |
| 2624 } | |
| 2625 | |
| 2626 /* Don't distribute current loop into too many loops given we don't have | |
| 2627 memory stream cost model. Be even more conservative in case of loop | |
| 2628 nest distribution. */ | |
| 2629 if ((same_type_p && num_builtin == 0) | |
| 2630 || (loop->inner != NULL | |
| 2631 && i >= NUM_PARTITION_THRESHOLD && num_normal > 1) | |
| 2632 || (loop->inner == NULL | |
| 2633 && i >= NUM_PARTITION_THRESHOLD && num_normal > num_builtin)) | |
| 2634 { | |
| 2635 a = (*partitions)[0]; | |
| 2636 for (i = 1; partitions->iterate (i, &partition); ++i) | |
| 2637 { | |
| 2638 partition_merge_into (NULL, a, partition, FUSE_FINALIZE); | |
| 2639 partition_free (partition); | |
| 2640 } | |
| 2641 partitions->truncate (1); | |
| 2642 } | |
| 2643 | |
| 2644 /* Fuse memset builtins if possible. */ | |
| 2645 if (partitions->length () > 1) | |
| 2646 fuse_memset_builtins (partitions); | |
| 2647 } | |
| 2648 | |
| 2649 /* Distributes the code from LOOP in such a way that producer statements | |
| 2650 are placed before consumer statements. Tries to separate only the | |
| 2651 statements from STMTS into separate loops. Returns the number of | |
| 2652 distributed loops. Set NB_CALLS to number of generated builtin calls. | |
| 2653 Set *DESTROY_P to whether LOOP needs to be destroyed. */ | |
| 0 | 2654 |
| 2655 static int | |
| 111 | 2656 distribute_loop (struct loop *loop, vec<gimple *> stmts, |
| 2657 control_dependences *cd, int *nb_calls, bool *destroy_p) | |
| 0 | 2658 { |
| 111 | 2659 ddrs_table = new hash_table<ddr_hasher> (389); |
| 0 | 2660 struct graph *rdg; |
| 111 | 2661 partition *partition; |
| 2662 bool any_builtin; | |
| 2663 int i, nbp; | |
| 2664 | |
| 2665 *destroy_p = false; | |
| 2666 *nb_calls = 0; | |
| 2667 loop_nest.create (0); | |
| 2668 if (!find_loop_nest (loop, &loop_nest)) | |
| 0 | 2669 { |
| 111 | 2670 loop_nest.release (); |
| 2671 delete ddrs_table; | |
| 2672 return 0; | |
| 0 | 2673 } |
| 2674 | |
| 111 | 2675 datarefs_vec.create (20); |
| 2676 rdg = build_rdg (loop, cd); | |
| 0 | 2677 if (!rdg) |
| 2678 { | |
| 2679 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2680 fprintf (dump_file, | |
| 111 | 2681 "Loop %d not distributed: failed to build the RDG.\n", |
| 0 | 2682 loop->num); |
| 2683 | |
| 111 | 2684 loop_nest.release (); |
| 2685 free_data_refs (datarefs_vec); | |
| 2686 delete ddrs_table; | |
| 2687 return 0; | |
| 0 | 2688 } |
| 2689 | |
| 111 | 2690 if (datarefs_vec.length () > MAX_DATAREFS_NUM) |
| 2691 { | |
| 2692 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2693 fprintf (dump_file, | |
| 2694 "Loop %d not distributed: too many memory references.\n", | |
| 2695 loop->num); | |
| 2696 | |
| 2697 free_rdg (rdg); | |
| 2698 loop_nest.release (); | |
| 2699 free_data_refs (datarefs_vec); | |
| 2700 delete ddrs_table; | |
| 2701 return 0; | |
| 2702 } | |
| 2703 | |
| 2704 data_reference_p dref; | |
| 2705 for (i = 0; datarefs_vec.iterate (i, &dref); ++i) | |
| 2706 dref->aux = (void *) (uintptr_t) i; | |
| 0 | 2707 |
| 2708 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2709 dump_rdg (dump_file, rdg); | |
| 2710 | |
| 111 | 2711 auto_vec<struct partition *, 3> partitions; |
| 2712 rdg_build_partitions (rdg, stmts, &partitions); | |
| 2713 | |
| 2714 auto_vec<ddr_p> alias_ddrs; | |
| 2715 | |
| 2716 auto_bitmap stmt_in_all_partitions; | |
| 2717 bitmap_copy (stmt_in_all_partitions, partitions[0]->stmts); | |
| 2718 for (i = 1; partitions.iterate (i, &partition); ++i) | |
| 2719 bitmap_and_into (stmt_in_all_partitions, partitions[i]->stmts); | |
| 2720 | |
| 2721 any_builtin = false; | |
| 2722 FOR_EACH_VEC_ELT (partitions, i, partition) | |
| 2723 { | |
| 2724 classify_partition (loop, rdg, partition, stmt_in_all_partitions); | |
| 2725 any_builtin |= partition_builtin_p (partition); | |
| 2726 } | |
| 2727 | |
| 2728 /* If we are only distributing patterns but did not detect any, | |
| 2729 simply bail out. */ | |
| 2730 if (!flag_tree_loop_distribution | |
| 2731 && !any_builtin) | |
| 2732 { | |
| 2733 nbp = 0; | |
| 2734 goto ldist_done; | |
| 2735 } | |
| 2736 | |
| 2737 /* If we are only distributing patterns fuse all partitions that | |
| 2738 were not classified as builtins. This also avoids chopping | |
| 2739 a loop into pieces, separated by builtin calls. That is, we | |
| 2740 only want no or a single loop body remaining. */ | |
| 2741 struct partition *into; | |
| 2742 if (!flag_tree_loop_distribution) | |
| 0 | 2743 { |
| 111 | 2744 for (i = 0; partitions.iterate (i, &into); ++i) |
| 2745 if (!partition_builtin_p (into)) | |
| 2746 break; | |
| 2747 for (++i; partitions.iterate (i, &partition); ++i) | |
| 2748 if (!partition_builtin_p (partition)) | |
| 2749 { | |
| 2750 partition_merge_into (NULL, into, partition, FUSE_NON_BUILTIN); | |
| 2751 partitions.unordered_remove (i); | |
| 2752 partition_free (partition); | |
| 2753 i--; | |
| 2754 } | |
| 2755 } | |
| 2756 | |
| 2757 /* Due to limitations in the transform phase we have to fuse all | |
| 2758 reduction partitions into the last partition so the existing | |
| 2759 loop will contain all loop-closed PHI nodes. */ | |
| 2760 for (i = 0; partitions.iterate (i, &into); ++i) | |
| 2761 if (partition_reduction_p (into)) | |
| 2762 break; | |
| 2763 for (i = i + 1; partitions.iterate (i, &partition); ++i) | |
| 2764 if (partition_reduction_p (partition)) | |
| 2765 { | |
| 2766 partition_merge_into (rdg, into, partition, FUSE_REDUCTION); | |
| 2767 partitions.unordered_remove (i); | |
| 2768 partition_free (partition); | |
| 2769 i--; | |
| 2770 } | |
| 2771 | |
| 2772 /* Apply our simple cost model - fuse partitions with similar | |
| 2773 memory accesses. */ | |
| 2774 for (i = 0; partitions.iterate (i, &into); ++i) | |
| 2775 { | |
| 2776 bool changed = false; | |
| 2777 if (partition_builtin_p (into)) | |
| 2778 continue; | |
| 2779 for (int j = i + 1; | |
| 2780 partitions.iterate (j, &partition); ++j) | |
| 0 | 2781 { |
| 111 | 2782 if (share_memory_accesses (rdg, into, partition)) |
| 2783 { | |
| 2784 partition_merge_into (rdg, into, partition, FUSE_SHARE_REF); | |
| 2785 partitions.unordered_remove (j); | |
| 2786 partition_free (partition); | |
| 2787 j--; | |
| 2788 changed = true; | |
| 2789 } | |
| 2790 } | |
| 2791 /* If we fused 0 1 2 in step 1 to 0,2 1 as 0 and 2 have similar | |
| 2792 accesses when 1 and 2 have similar accesses but not 0 and 1 | |
| 2793 then in the next iteration we will fail to consider merging | |
| 2794 1 into 0,2. So try again if we did any merging into 0. */ | |
| 2795 if (changed) | |
| 2796 i--; | |
| 2797 } | |
| 2798 | |
| 2799 /* Build the partition dependency graph and fuse partitions in strong | |
| 2800 connected component. */ | |
| 2801 if (partitions.length () > 1) | |
| 2802 { | |
| 2803 /* Don't support loop nest distribution under runtime alias check | |
| 2804 since it's not likely to enable many vectorization opportunities. */ | |
| 2805 if (loop->inner) | |
| 2806 merge_dep_scc_partitions (rdg, &partitions, false); | |
| 2807 else | |
| 2808 { | |
| 2809 merge_dep_scc_partitions (rdg, &partitions, true); | |
| 2810 if (partitions.length () > 1) | |
| 2811 break_alias_scc_partitions (rdg, &partitions, &alias_ddrs); | |
| 0 | 2812 } |
| 2813 } | |
| 2814 | |
| 111 | 2815 finalize_partitions (loop, &partitions, &alias_ddrs); |
| 2816 | |
| 2817 nbp = partitions.length (); | |
| 2818 if (nbp == 0 | |
| 2819 || (nbp == 1 && !partition_builtin_p (partitions[0])) | |
| 2820 || (nbp > 1 && partition_contains_all_rw (rdg, partitions))) | |
| 2821 { | |
| 2822 nbp = 0; | |
| 2823 goto ldist_done; | |
| 2824 } | |
| 2825 | |
| 2826 if (version_for_distribution_p (&partitions, &alias_ddrs)) | |
| 2827 version_loop_by_alias_check (loop, &alias_ddrs); | |
| 2828 | |
| 2829 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 2830 { | |
| 2831 fprintf (dump_file, | |
| 2832 "distribute loop <%d> into partitions:\n", loop->num); | |
| 2833 dump_rdg_partitions (dump_file, partitions); | |
| 2834 } | |
| 2835 | |
| 2836 FOR_EACH_VEC_ELT (partitions, i, partition) | |
| 2837 { | |
| 2838 if (partition_builtin_p (partition)) | |
| 2839 (*nb_calls)++; | |
| 2840 *destroy_p |= generate_code_for_partition (loop, partition, i < nbp - 1); | |
| 2841 } | |
| 2842 | |
| 2843 ldist_done: | |
| 2844 loop_nest.release (); | |
| 2845 free_data_refs (datarefs_vec); | |
| 2846 for (hash_table<ddr_hasher>::iterator iter = ddrs_table->begin (); | |
| 2847 iter != ddrs_table->end (); ++iter) | |
| 2848 { | |
| 2849 free_dependence_relation (*iter); | |
| 2850 *iter = NULL; | |
| 2851 } | |
| 2852 delete ddrs_table; | |
| 2853 | |
| 2854 FOR_EACH_VEC_ELT (partitions, i, partition) | |
| 2855 partition_free (partition); | |
| 2856 | |
| 0 | 2857 free_rdg (rdg); |
| 111 | 2858 return nbp - *nb_calls; |
| 0 | 2859 } |
| 2860 | |
| 2861 /* Distribute all loops in the current function. */ | |
| 2862 | |
| 111 | 2863 namespace { |
| 2864 | |
| 2865 const pass_data pass_data_loop_distribution = | |
| 2866 { | |
| 2867 GIMPLE_PASS, /* type */ | |
| 2868 "ldist", /* name */ | |
| 2869 OPTGROUP_LOOP, /* optinfo_flags */ | |
| 2870 TV_TREE_LOOP_DISTRIBUTION, /* tv_id */ | |
| 2871 ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
| 2872 0, /* properties_provided */ | |
| 2873 0, /* properties_destroyed */ | |
| 2874 0, /* todo_flags_start */ | |
| 2875 0, /* todo_flags_finish */ | |
| 2876 }; | |
| 2877 | |
| 2878 class pass_loop_distribution : public gimple_opt_pass | |
| 2879 { | |
| 2880 public: | |
| 2881 pass_loop_distribution (gcc::context *ctxt) | |
| 2882 : gimple_opt_pass (pass_data_loop_distribution, ctxt) | |
| 2883 {} | |
| 2884 | |
| 2885 /* opt_pass methods: */ | |
| 2886 virtual bool gate (function *) | |
| 2887 { | |
| 2888 return flag_tree_loop_distribution | |
| 2889 || flag_tree_loop_distribute_patterns; | |
| 2890 } | |
| 2891 | |
| 2892 virtual unsigned int execute (function *); | |
| 2893 | |
| 2894 }; // class pass_loop_distribution | |
| 2895 | |
| 2896 | |
| 2897 /* Given LOOP, this function records seed statements for distribution in | |
| 2898 WORK_LIST. Return false if there is nothing for distribution. */ | |
| 2899 | |
| 2900 static bool | |
| 2901 find_seed_stmts_for_distribution (struct loop *loop, vec<gimple *> *work_list) | |
| 2902 { | |
| 2903 basic_block *bbs = get_loop_body_in_dom_order (loop); | |
| 2904 | |
| 2905 /* Initialize the worklist with stmts we seed the partitions with. */ | |
| 2906 for (unsigned i = 0; i < loop->num_nodes; ++i) | |
| 2907 { | |
| 2908 for (gphi_iterator gsi = gsi_start_phis (bbs[i]); | |
| 2909 !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 2910 { | |
| 2911 gphi *phi = gsi.phi (); | |
| 2912 if (virtual_operand_p (gimple_phi_result (phi))) | |
| 2913 continue; | |
| 2914 /* Distribute stmts which have defs that are used outside of | |
| 2915 the loop. */ | |
| 2916 if (!stmt_has_scalar_dependences_outside_loop (loop, phi)) | |
| 2917 continue; | |
| 2918 work_list->safe_push (phi); | |
| 2919 } | |
| 2920 for (gimple_stmt_iterator gsi = gsi_start_bb (bbs[i]); | |
| 2921 !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 2922 { | |
| 2923 gimple *stmt = gsi_stmt (gsi); | |
| 2924 | |
| 2925 /* If there is a stmt with side-effects bail out - we | |
| 2926 cannot and should not distribute this loop. */ | |
| 2927 if (gimple_has_side_effects (stmt)) | |
| 2928 { | |
| 2929 free (bbs); | |
| 2930 return false; | |
| 2931 } | |
| 2932 | |
| 2933 /* Distribute stmts which have defs that are used outside of | |
| 2934 the loop. */ | |
| 2935 if (stmt_has_scalar_dependences_outside_loop (loop, stmt)) | |
| 2936 ; | |
| 2937 /* Otherwise only distribute stores for now. */ | |
| 2938 else if (!gimple_vdef (stmt)) | |
| 2939 continue; | |
| 2940 | |
| 2941 work_list->safe_push (stmt); | |
| 2942 } | |
| 2943 } | |
| 2944 free (bbs); | |
| 2945 return work_list->length () > 0; | |
| 2946 } | |
| 2947 | |
| 2948 /* Given innermost LOOP, return the outermost enclosing loop that forms a | |
| 2949 perfect loop nest. */ | |
| 2950 | |
| 2951 static struct loop * | |
| 2952 prepare_perfect_loop_nest (struct loop *loop) | |
| 2953 { | |
| 2954 struct loop *outer = loop_outer (loop); | |
| 2955 tree niters = number_of_latch_executions (loop); | |
| 2956 | |
| 2957 /* TODO: We only support the innermost 2-level loop nest distribution | |
| 2958 because of compilation time issue for now. This should be relaxed | |
| 2959 in the future. */ | |
| 2960 while (loop->inner == NULL | |
| 2961 && loop_outer (outer) | |
| 2962 && outer->inner == loop && loop->next == NULL | |
| 2963 && single_exit (outer) | |
| 2964 && optimize_loop_for_speed_p (outer) | |
| 2965 && !chrec_contains_symbols_defined_in_loop (niters, outer->num) | |
| 2966 && (niters = number_of_latch_executions (outer)) != NULL_TREE | |
| 2967 && niters != chrec_dont_know) | |
| 2968 { | |
| 2969 loop = outer; | |
| 2970 outer = loop_outer (loop); | |
| 2971 } | |
| 2972 | |
| 2973 return loop; | |
| 2974 } | |
| 2975 | |
| 2976 unsigned int | |
| 2977 pass_loop_distribution::execute (function *fun) | |
| 0 | 2978 { |
| 2979 struct loop *loop; | |
| 111 | 2980 bool changed = false; |
| 2981 basic_block bb; | |
| 2982 control_dependences *cd = NULL; | |
| 2983 auto_vec<loop_p> loops_to_be_destroyed; | |
| 2984 | |
| 2985 if (number_of_loops (fun) <= 1) | |
| 2986 return 0; | |
| 2987 | |
| 2988 /* Compute topological order for basic blocks. Topological order is | |
| 2989 needed because data dependence is computed for data references in | |
| 2990 lexicographical order. */ | |
| 2991 if (bb_top_order_index == NULL) | |
| 0 | 2992 { |
| 111 | 2993 int rpo_num; |
| 2994 int *rpo = XNEWVEC (int, last_basic_block_for_fn (cfun)); | |
| 2995 | |
| 2996 bb_top_order_index = XNEWVEC (int, last_basic_block_for_fn (cfun)); | |
| 2997 bb_top_order_index_size = last_basic_block_for_fn (cfun); | |
| 2998 rpo_num = pre_and_rev_post_order_compute_fn (cfun, NULL, rpo, true); | |
| 2999 for (int i = 0; i < rpo_num; i++) | |
| 3000 bb_top_order_index[rpo[i]] = i; | |
| 3001 | |
| 3002 free (rpo); | |
| 3003 } | |
| 3004 | |
| 3005 FOR_ALL_BB_FN (bb, fun) | |
| 3006 { | |
| 3007 gimple_stmt_iterator gsi; | |
| 3008 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 3009 gimple_set_uid (gsi_stmt (gsi), -1); | |
| 3010 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 3011 gimple_set_uid (gsi_stmt (gsi), -1); | |
| 3012 } | |
| 3013 | |
| 3014 /* We can at the moment only distribute non-nested loops, thus restrict | |
| 3015 walking to innermost loops. */ | |
| 3016 FOR_EACH_LOOP (loop, LI_ONLY_INNERMOST) | |
| 3017 { | |
| 3018 /* Don't distribute multiple exit edges loop, or cold loop. */ | |
| 3019 if (!single_exit (loop) | |
| 3020 || !optimize_loop_for_speed_p (loop)) | |
|
67
f6334be47118
update gcc from gcc-4.6-20100522 to gcc-4.6-20110318
nobuyasu <dimolto@cr.ie.u-ryukyu.ac.jp>
parents:
63
diff
changeset
|
3021 continue; |
| 0 | 3022 |
| 111 | 3023 /* Don't distribute loop if niters is unknown. */ |
| 3024 tree niters = number_of_latch_executions (loop); | |
| 3025 if (niters == NULL_TREE || niters == chrec_dont_know) | |
| 3026 continue; | |
| 3027 | |
| 3028 /* Get the perfect loop nest for distribution. */ | |
| 3029 loop = prepare_perfect_loop_nest (loop); | |
| 3030 for (; loop; loop = loop->inner) | |
|
67
f6334be47118
update gcc from gcc-4.6-20100522 to gcc-4.6-20110318
nobuyasu <dimolto@cr.ie.u-ryukyu.ac.jp>
parents:
63
diff
changeset
|
3031 { |
| 111 | 3032 auto_vec<gimple *> work_list; |
| 3033 if (!find_seed_stmts_for_distribution (loop, &work_list)) | |
| 3034 break; | |
| 3035 | |
| 3036 const char *str = loop->inner ? " nest" : ""; | |
| 3037 location_t loc = find_loop_location (loop); | |
| 3038 if (!cd) | |
| 3039 { | |
| 3040 calculate_dominance_info (CDI_DOMINATORS); | |
| 3041 calculate_dominance_info (CDI_POST_DOMINATORS); | |
| 3042 cd = new control_dependences (); | |
| 3043 free_dominance_info (CDI_POST_DOMINATORS); | |
| 3044 } | |
| 3045 | |
| 3046 bool destroy_p; | |
| 3047 int nb_generated_loops, nb_generated_calls; | |
| 3048 nb_generated_loops = distribute_loop (loop, work_list, cd, | |
| 3049 &nb_generated_calls, | |
| 3050 &destroy_p); | |
| 3051 if (destroy_p) | |
| 3052 loops_to_be_destroyed.safe_push (loop); | |
| 3053 | |
| 3054 if (nb_generated_loops + nb_generated_calls > 0) | |
| 3055 { | |
| 3056 changed = true; | |
| 3057 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, | |
| 3058 loc, "Loop%s %d distributed: split to %d loops " | |
| 3059 "and %d library calls.\n", str, loop->num, | |
| 3060 nb_generated_loops, nb_generated_calls); | |
| 3061 | |
| 3062 break; | |
| 3063 } | |
| 3064 | |
| 3065 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 3066 fprintf (dump_file, "Loop%s %d not distributed.\n", str, loop->num); | |
|
67
f6334be47118
update gcc from gcc-4.6-20100522 to gcc-4.6-20110318
nobuyasu <dimolto@cr.ie.u-ryukyu.ac.jp>
parents:
63
diff
changeset
|
3067 } |
| 111 | 3068 } |
| 3069 | |
| 3070 if (cd) | |
| 3071 delete cd; | |
| 3072 | |
| 3073 if (bb_top_order_index != NULL) | |
| 3074 { | |
| 3075 free (bb_top_order_index); | |
| 3076 bb_top_order_index = NULL; | |
| 3077 bb_top_order_index_size = 0; | |
| 0 | 3078 } |
| 3079 | |
| 111 | 3080 if (changed) |
| 3081 { | |
| 3082 /* Destroy loop bodies that could not be reused. Do this late as we | |
| 3083 otherwise can end up refering to stale data in control dependences. */ | |
| 3084 unsigned i; | |
| 3085 FOR_EACH_VEC_ELT (loops_to_be_destroyed, i, loop) | |
| 3086 destroy_loop (loop); | |
| 3087 | |
| 3088 /* Cached scalar evolutions now may refer to wrong or non-existing | |
| 3089 loops. */ | |
| 3090 scev_reset_htab (); | |
| 3091 mark_virtual_operands_for_renaming (fun); | |
| 3092 rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); | |
| 3093 } | |
| 3094 | |
| 3095 checking_verify_loop_structure (); | |
| 3096 | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
3097 return 0; |
| 0 | 3098 } |
| 3099 | |
| 111 | 3100 } // anon namespace |
| 3101 | |
| 3102 gimple_opt_pass * | |
| 3103 make_pass_loop_distribution (gcc::context *ctxt) | |
| 0 | 3104 { |
| 111 | 3105 return new pass_loop_distribution (ctxt); |
| 3106 } |