Mercurial > hg > CbC > CbC_gcc
annotate gcc/tree-ssa-loop-ch.c @ 145:1830386684a0
gcc-9.2.0
| author | anatofuz |
|---|---|
| date | Thu, 13 Feb 2020 11:34:05 +0900 |
| parents | 84e7813d76e9 |
| children |
| rev | line source |
|---|---|
| 0 | 1 /* Loop header copying on trees. |
| 145 | 2 Copyright (C) 2004-2020 Free Software Foundation, Inc. |
|
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3 |
| 0 | 4 This file is part of GCC. |
|
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5 |
| 0 | 6 GCC is free software; you can redistribute it and/or modify it |
| 7 under the terms of the GNU General Public License as published by the | |
| 8 Free Software Foundation; either version 3, or (at your option) any | |
| 9 later version. | |
|
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10 |
| 0 | 11 GCC is distributed in the hope that it will be useful, but WITHOUT |
| 12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 14 for more details. | |
|
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15 |
| 0 | 16 You should have received a copy of the GNU General Public License |
| 17 along with GCC; see the file COPYING3. If not see | |
| 18 <http://www.gnu.org/licenses/>. */ | |
| 19 | |
| 20 #include "config.h" | |
| 21 #include "system.h" | |
| 22 #include "coretypes.h" | |
| 111 | 23 #include "backend.h" |
| 0 | 24 #include "tree.h" |
| 111 | 25 #include "gimple.h" |
| 26 #include "cfghooks.h" | |
| 0 | 27 #include "tree-pass.h" |
| 111 | 28 #include "gimple-ssa.h" |
| 29 #include "gimple-iterator.h" | |
| 30 #include "tree-cfg.h" | |
| 31 #include "tree-into-ssa.h" | |
| 0 | 32 #include "cfgloop.h" |
| 33 #include "tree-inline.h" | |
| 111 | 34 #include "tree-ssa-scopedtables.h" |
| 35 #include "tree-ssa-threadedge.h" | |
| 145 | 36 #include "tree-ssa-sccvn.h" |
| 37 #include "tree-phinodes.h" | |
| 38 #include "ssa-iterators.h" | |
| 0 | 39 |
| 40 /* Duplicates headers of loops if they are small enough, so that the statements | |
| 41 in the loop body are always executed when the loop is entered. This | |
| 42 increases effectiveness of code motion optimizations, and reduces the need | |
| 43 for loop preconditioning. */ | |
| 44 | |
| 45 /* Check whether we should duplicate HEADER of LOOP. At most *LIMIT | |
| 46 instructions should be duplicated, limit is decreased by the actual | |
| 47 amount. */ | |
| 48 | |
| 49 static bool | |
| 145 | 50 should_duplicate_loop_header_p (basic_block header, class loop *loop, |
| 0 | 51 int *limit) |
| 52 { | |
| 53 gimple_stmt_iterator bsi; | |
| 54 | |
| 111 | 55 gcc_assert (!header->aux); |
| 0 | 56 |
| 57 /* Loop header copying usually increases size of the code. This used not to | |
| 58 be true, since quite often it is possible to verify that the condition is | |
| 59 satisfied in the first iteration and therefore to eliminate it. Jump | |
| 60 threading handles these cases now. */ | |
| 131 | 61 if (optimize_loop_for_size_p (loop) |
| 62 && !loop->force_vectorize) | |
| 111 | 63 { |
| 64 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 65 fprintf (dump_file, | |
| 66 " Not duplicating bb %i: optimizing for size.\n", | |
| 67 header->index); | |
| 68 return false; | |
| 69 } | |
| 0 | 70 |
| 71 gcc_assert (EDGE_COUNT (header->succs) > 0); | |
| 72 if (single_succ_p (header)) | |
| 111 | 73 { |
| 74 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 75 fprintf (dump_file, | |
| 76 " Not duplicating bb %i: it is single succ.\n", | |
| 77 header->index); | |
| 78 return false; | |
| 79 } | |
| 80 | |
| 0 | 81 if (flow_bb_inside_loop_p (loop, EDGE_SUCC (header, 0)->dest) |
| 82 && flow_bb_inside_loop_p (loop, EDGE_SUCC (header, 1)->dest)) | |
| 111 | 83 { |
| 84 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 85 fprintf (dump_file, | |
| 86 " Not duplicating bb %i: both sucessors are in loop.\n", | |
| 87 loop->num); | |
| 88 return false; | |
| 89 } | |
| 0 | 90 |
| 91 /* If this is not the original loop header, we want it to have just | |
| 92 one predecessor in order to match the && pattern. */ | |
| 93 if (header != loop->header && !single_pred_p (header)) | |
| 111 | 94 { |
| 95 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 96 fprintf (dump_file, | |
| 97 " Not duplicating bb %i: it has mutiple predecestors.\n", | |
| 98 header->index); | |
| 99 return false; | |
| 100 } | |
| 0 | 101 |
| 145 | 102 gcond *last = safe_dyn_cast <gcond *> (last_stmt (header)); |
| 103 if (!last) | |
| 111 | 104 { |
| 105 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 106 fprintf (dump_file, | |
| 107 " Not duplicating bb %i: it does not end by conditional.\n", | |
| 108 header->index); | |
| 109 return false; | |
| 110 } | |
| 0 | 111 |
| 145 | 112 for (gphi_iterator psi = gsi_start_phis (header); !gsi_end_p (psi); |
| 113 gsi_next (&psi)) | |
| 114 { | |
| 115 gphi *phi = psi.phi (); | |
| 116 tree res = gimple_phi_result (phi); | |
| 117 if (INTEGRAL_TYPE_P (TREE_TYPE (res)) | |
| 118 || POINTER_TYPE_P (TREE_TYPE (res))) | |
| 119 gimple_set_uid (phi, 1 /* IV */); | |
| 120 else | |
| 121 gimple_set_uid (phi, 0); | |
| 122 } | |
| 123 | |
| 124 /* Count number of instructions and punt on calls. | |
| 125 Populate stmts INV/IV flag to later apply heuristics to the | |
| 126 kind of conditions we want to copy. */ | |
| 0 | 127 for (bsi = gsi_start_bb (header); !gsi_end_p (bsi); gsi_next (&bsi)) |
| 128 { | |
| 145 | 129 gimple *last = gsi_stmt (bsi); |
| 0 | 130 |
| 131 if (gimple_code (last) == GIMPLE_LABEL) | |
| 132 continue; | |
| 133 | |
|
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134 if (is_gimple_debug (last)) |
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135 continue; |
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136 |
| 111 | 137 if (gimple_code (last) == GIMPLE_CALL |
| 138 && (!gimple_inexpensive_call_p (as_a <gcall *> (last)) | |
| 139 /* IFN_LOOP_DIST_ALIAS means that inner loop is distributed | |
| 140 at current loop's header. Don't copy in this case. */ | |
| 141 || gimple_call_internal_p (last, IFN_LOOP_DIST_ALIAS))) | |
| 142 { | |
| 143 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 144 fprintf (dump_file, | |
| 145 " Not duplicating bb %i: it contains call.\n", | |
| 146 header->index); | |
| 147 return false; | |
| 148 } | |
| 0 | 149 |
| 150 *limit -= estimate_num_insns (last, &eni_size_weights); | |
| 151 if (*limit < 0) | |
| 111 | 152 { |
| 153 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 154 fprintf (dump_file, | |
| 155 " Not duplicating bb %i contains too many insns.\n", | |
| 156 header->index); | |
| 157 return false; | |
| 158 } | |
| 145 | 159 |
| 160 /* Classify the stmt based on whether its computation is based | |
| 161 on a IV or whether it is invariant in the loop. */ | |
| 162 gimple_set_uid (last, 0); | |
| 163 if (!gimple_vuse (last)) | |
| 164 { | |
| 165 bool inv = true; | |
| 166 bool iv = false; | |
| 167 ssa_op_iter i; | |
| 168 tree op; | |
| 169 FOR_EACH_SSA_TREE_OPERAND (op, last, i, SSA_OP_USE) | |
| 170 if (!SSA_NAME_IS_DEFAULT_DEF (op) | |
| 171 && flow_bb_inside_loop_p (loop, | |
| 172 gimple_bb (SSA_NAME_DEF_STMT (op)))) | |
| 173 { | |
| 174 if (!(gimple_uid (SSA_NAME_DEF_STMT (op)) & 2 /* INV */)) | |
| 175 inv = false; | |
| 176 if (gimple_uid (SSA_NAME_DEF_STMT (op)) & 1 /* IV */) | |
| 177 iv = true; | |
| 178 } | |
| 179 gimple_set_uid (last, (iv ? 1 : 0) | (inv ? 2 : 0)); | |
| 180 } | |
| 0 | 181 } |
| 145 | 182 |
| 183 /* If the condition tests a non-IV loop variant we do not want to rotate | |
| 184 the loop further. Unless this is the original loop header. */ | |
| 185 tree lhs = gimple_cond_lhs (last); | |
| 186 tree rhs = gimple_cond_rhs (last); | |
| 187 if (header != loop->header | |
| 188 && ((TREE_CODE (lhs) == SSA_NAME | |
| 189 && !SSA_NAME_IS_DEFAULT_DEF (lhs) | |
| 190 && flow_bb_inside_loop_p (loop, gimple_bb (SSA_NAME_DEF_STMT (lhs))) | |
| 191 && gimple_uid (SSA_NAME_DEF_STMT (lhs)) == 0) | |
| 192 || (TREE_CODE (rhs) == SSA_NAME | |
| 193 && !SSA_NAME_IS_DEFAULT_DEF (rhs) | |
| 194 && flow_bb_inside_loop_p (loop, | |
| 195 gimple_bb (SSA_NAME_DEF_STMT (rhs))) | |
| 196 && gimple_uid (SSA_NAME_DEF_STMT (rhs)) == 0))) | |
| 197 { | |
| 198 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 199 fprintf (dump_file, | |
| 200 " Not duplicating bb %i: condition based on non-IV loop" | |
| 201 " variant.\n", header->index); | |
| 202 return false; | |
| 203 } | |
| 204 | |
| 111 | 205 if (dump_file && (dump_flags & TDF_DETAILS)) |
| 206 fprintf (dump_file, " Will duplicate bb %i\n", header->index); | |
| 0 | 207 return true; |
| 208 } | |
| 209 | |
| 210 /* Checks whether LOOP is a do-while style loop. */ | |
| 211 | |
| 212 static bool | |
| 145 | 213 do_while_loop_p (class loop *loop) |
| 0 | 214 { |
| 111 | 215 gimple *stmt = last_stmt (loop->latch); |
| 0 | 216 |
| 217 /* If the latch of the loop is not empty, it is not a do-while loop. */ | |
| 218 if (stmt | |
| 219 && gimple_code (stmt) != GIMPLE_LABEL) | |
| 111 | 220 { |
| 221 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 222 fprintf (dump_file, | |
| 223 "Loop %i is not do-while loop: latch is not empty.\n", | |
| 224 loop->num); | |
| 225 return false; | |
| 226 } | |
| 0 | 227 |
| 131 | 228 /* If the latch does not have a single predecessor, it is not a |
| 229 do-while loop. */ | |
| 230 if (!single_pred_p (loop->latch)) | |
| 111 | 231 { |
| 232 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 233 fprintf (dump_file, | |
| 131 | 234 "Loop %i is not do-while loop: latch has multiple " |
| 235 "predecessors.\n", loop->num); | |
| 111 | 236 return false; |
| 237 } | |
| 131 | 238 |
| 239 /* If the latch predecessor doesn't exit the loop, it is not a | |
| 240 do-while loop. */ | |
| 241 if (!loop_exits_from_bb_p (loop, single_pred (loop->latch))) | |
| 242 { | |
| 243 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 244 fprintf (dump_file, | |
| 245 "Loop %i is not do-while loop: latch predecessor " | |
| 246 "does not exit loop.\n", loop->num); | |
| 247 return false; | |
| 248 } | |
| 249 | |
| 111 | 250 if (dump_file && (dump_flags & TDF_DETAILS)) |
| 251 fprintf (dump_file, "Loop %i is do-while loop\n", loop->num); | |
| 0 | 252 |
| 253 return true; | |
| 254 } | |
| 255 | |
| 111 | 256 namespace { |
| 257 | |
| 258 /* Common superclass for both header-copying phases. */ | |
| 259 class ch_base : public gimple_opt_pass | |
| 260 { | |
| 261 protected: | |
| 262 ch_base (pass_data data, gcc::context *ctxt) | |
| 263 : gimple_opt_pass (data, ctxt) | |
| 264 {} | |
| 265 | |
| 266 /* Copies headers of all loops in FUN for which process_loop_p is true. */ | |
| 267 unsigned int copy_headers (function *fun); | |
| 268 | |
| 269 /* Return true to copy headers of LOOP or false to skip. */ | |
| 145 | 270 virtual bool process_loop_p (class loop *loop) = 0; |
| 111 | 271 }; |
| 272 | |
| 273 const pass_data pass_data_ch = | |
| 274 { | |
| 275 GIMPLE_PASS, /* type */ | |
| 276 "ch", /* name */ | |
| 277 OPTGROUP_LOOP, /* optinfo_flags */ | |
| 278 TV_TREE_CH, /* tv_id */ | |
| 279 ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
| 280 0, /* properties_provided */ | |
| 281 0, /* properties_destroyed */ | |
| 282 0, /* todo_flags_start */ | |
| 283 0, /* todo_flags_finish */ | |
| 284 }; | |
| 285 | |
| 286 class pass_ch : public ch_base | |
| 287 { | |
| 288 public: | |
| 289 pass_ch (gcc::context *ctxt) | |
| 290 : ch_base (pass_data_ch, ctxt) | |
| 291 {} | |
| 292 | |
| 293 /* opt_pass methods: */ | |
| 294 virtual bool gate (function *) { return flag_tree_ch != 0; } | |
| 295 | |
| 296 /* Initialize and finalize loop structures, copying headers inbetween. */ | |
| 297 virtual unsigned int execute (function *); | |
| 298 | |
| 299 opt_pass * clone () { return new pass_ch (m_ctxt); } | |
| 300 | |
| 301 protected: | |
| 302 /* ch_base method: */ | |
| 145 | 303 virtual bool process_loop_p (class loop *loop); |
| 111 | 304 }; // class pass_ch |
| 305 | |
| 306 const pass_data pass_data_ch_vect = | |
| 307 { | |
| 308 GIMPLE_PASS, /* type */ | |
| 309 "ch_vect", /* name */ | |
| 310 OPTGROUP_LOOP, /* optinfo_flags */ | |
| 311 TV_TREE_CH, /* tv_id */ | |
| 312 ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
| 313 0, /* properties_provided */ | |
| 314 0, /* properties_destroyed */ | |
| 315 0, /* todo_flags_start */ | |
| 316 0, /* todo_flags_finish */ | |
| 317 }; | |
| 318 | |
| 319 /* This is a more aggressive version of the same pass, designed to run just | |
| 320 before if-conversion and vectorization, to put more loops into the form | |
| 321 required for those phases. */ | |
| 322 class pass_ch_vect : public ch_base | |
| 323 { | |
| 324 public: | |
| 325 pass_ch_vect (gcc::context *ctxt) | |
| 326 : ch_base (pass_data_ch_vect, ctxt) | |
| 327 {} | |
| 328 | |
| 329 /* opt_pass methods: */ | |
| 330 virtual bool gate (function *fun) | |
| 331 { | |
| 332 return flag_tree_ch != 0 | |
| 333 && (flag_tree_loop_vectorize != 0 || fun->has_force_vectorize_loops); | |
| 334 } | |
| 335 | |
| 336 /* Just copy headers, no initialization/finalization of loop structures. */ | |
| 337 virtual unsigned int execute (function *); | |
| 338 | |
| 339 protected: | |
| 340 /* ch_base method: */ | |
| 145 | 341 virtual bool process_loop_p (class loop *loop); |
| 111 | 342 }; // class pass_ch_vect |
| 343 | |
| 0 | 344 /* For all loops, copy the condition at the end of the loop body in front |
| 345 of the loop. This is beneficial since it increases efficiency of | |
| 346 code motion optimizations. It also saves one jump on entry to the loop. */ | |
| 347 | |
| 111 | 348 unsigned int |
| 349 ch_base::copy_headers (function *fun) | |
| 0 | 350 { |
| 145 | 351 class loop *loop; |
| 0 | 352 basic_block header; |
| 353 edge exit, entry; | |
| 354 basic_block *bbs, *copied_bbs; | |
| 355 unsigned n_bbs; | |
| 356 unsigned bbs_size; | |
| 111 | 357 bool changed = false; |
| 0 | 358 |
| 111 | 359 if (number_of_loops (fun) <= 1) |
| 145 | 360 return 0; |
| 0 | 361 |
| 111 | 362 bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (fun)); |
| 363 copied_bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (fun)); | |
| 364 bbs_size = n_basic_blocks_for_fn (fun); | |
| 0 | 365 |
| 145 | 366 auto_vec<std::pair<edge, loop_p> > copied; |
| 367 | |
| 111 | 368 FOR_EACH_LOOP (loop, 0) |
| 0 | 369 { |
| 145 | 370 int initial_limit = param_max_loop_header_insns; |
| 111 | 371 int remaining_limit = initial_limit; |
| 372 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 373 fprintf (dump_file, | |
| 374 "Analyzing loop %i\n", loop->num); | |
| 0 | 375 |
| 376 header = loop->header; | |
| 377 | |
| 378 /* If the loop is already a do-while style one (either because it was | |
| 379 written as such, or because jump threading transformed it into one), | |
| 380 we might be in fact peeling the first iteration of the loop. This | |
| 131 | 381 in general is not a good idea. Also avoid touching infinite loops. */ |
| 382 if (!loop_has_exit_edges (loop) | |
| 383 || !process_loop_p (loop)) | |
| 0 | 384 continue; |
| 385 | |
| 386 /* Iterate the header copying up to limit; this takes care of the cases | |
| 387 like while (a && b) {...}, where we want to have both of the conditions | |
| 388 copied. TODO -- handle while (a || b) - like cases, by not requiring | |
| 389 the header to have just a single successor and copying up to | |
| 390 postdominator. */ | |
| 391 | |
| 392 exit = NULL; | |
| 393 n_bbs = 0; | |
| 111 | 394 while (should_duplicate_loop_header_p (header, loop, &remaining_limit)) |
| 0 | 395 { |
| 396 /* Find a successor of header that is inside a loop; i.e. the new | |
| 397 header after the condition is copied. */ | |
| 398 if (flow_bb_inside_loop_p (loop, EDGE_SUCC (header, 0)->dest)) | |
| 399 exit = EDGE_SUCC (header, 0); | |
| 400 else | |
| 401 exit = EDGE_SUCC (header, 1); | |
| 402 bbs[n_bbs++] = header; | |
| 403 gcc_assert (bbs_size > n_bbs); | |
| 404 header = exit->dest; | |
| 405 } | |
| 406 | |
| 407 if (!exit) | |
| 408 continue; | |
| 409 | |
| 410 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 411 fprintf (dump_file, | |
| 111 | 412 "Duplicating header of the loop %d up to edge %d->%d," |
| 413 " %i insns.\n", | |
| 414 loop->num, exit->src->index, exit->dest->index, | |
| 415 initial_limit - remaining_limit); | |
| 0 | 416 |
| 417 /* Ensure that the header will have just the latch as a predecessor | |
| 418 inside the loop. */ | |
| 419 if (!single_pred_p (exit->dest)) | |
| 420 exit = single_pred_edge (split_edge (exit)); | |
| 421 | |
| 422 entry = loop_preheader_edge (loop); | |
| 423 | |
| 111 | 424 propagate_threaded_block_debug_into (exit->dest, entry->dest); |
| 425 if (!gimple_duplicate_sese_region (entry, exit, bbs, n_bbs, copied_bbs, | |
| 426 true)) | |
| 0 | 427 { |
| 428 fprintf (dump_file, "Duplication failed.\n"); | |
| 429 continue; | |
| 430 } | |
| 145 | 431 copied.safe_push (std::make_pair (entry, loop)); |
| 0 | 432 |
| 433 /* If the loop has the form "for (i = j; i < j + 10; i++)" then | |
| 434 this copying can introduce a case where we rely on undefined | |
| 435 signed overflow to eliminate the preheader condition, because | |
| 436 we assume that "j < j + 10" is true. We don't want to warn | |
| 437 about that case for -Wstrict-overflow, because in general we | |
| 438 don't warn about overflow involving loops. Prevent the | |
| 439 warning by setting the no_warning flag in the condition. */ | |
| 440 if (warn_strict_overflow > 0) | |
| 441 { | |
| 442 unsigned int i; | |
| 443 | |
| 444 for (i = 0; i < n_bbs; ++i) | |
| 445 { | |
| 446 gimple_stmt_iterator bsi; | |
| 447 | |
| 448 for (bsi = gsi_start_bb (copied_bbs[i]); | |
| 449 !gsi_end_p (bsi); | |
| 450 gsi_next (&bsi)) | |
| 451 { | |
| 111 | 452 gimple *stmt = gsi_stmt (bsi); |
| 0 | 453 if (gimple_code (stmt) == GIMPLE_COND) |
| 145 | 454 { |
| 455 tree lhs = gimple_cond_lhs (stmt); | |
| 456 if (gimple_cond_code (stmt) != EQ_EXPR | |
| 457 && gimple_cond_code (stmt) != NE_EXPR | |
| 458 && INTEGRAL_TYPE_P (TREE_TYPE (lhs)) | |
| 459 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (lhs))) | |
| 460 gimple_set_no_warning (stmt, true); | |
| 461 } | |
| 0 | 462 else if (is_gimple_assign (stmt)) |
| 463 { | |
| 464 enum tree_code rhs_code = gimple_assign_rhs_code (stmt); | |
| 145 | 465 tree rhs1 = gimple_assign_rhs1 (stmt); |
| 466 if (TREE_CODE_CLASS (rhs_code) == tcc_comparison | |
| 467 && rhs_code != EQ_EXPR | |
| 468 && rhs_code != NE_EXPR | |
| 469 && INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
| 470 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (rhs1))) | |
| 0 | 471 gimple_set_no_warning (stmt, true); |
| 472 } | |
| 473 } | |
| 474 } | |
| 475 } | |
| 476 | |
| 477 /* Ensure that the latch and the preheader is simple (we know that they | |
| 478 are not now, since there was the loop exit condition. */ | |
| 479 split_edge (loop_preheader_edge (loop)); | |
| 480 split_edge (loop_latch_edge (loop)); | |
| 111 | 481 |
| 131 | 482 if (dump_file && (dump_flags & TDF_DETAILS)) |
| 483 { | |
| 484 if (do_while_loop_p (loop)) | |
| 485 fprintf (dump_file, "Loop %d is now do-while loop.\n", loop->num); | |
| 486 else | |
| 487 fprintf (dump_file, "Loop %d is still not do-while loop.\n", | |
| 488 loop->num); | |
| 489 } | |
| 490 | |
| 111 | 491 changed = true; |
| 0 | 492 } |
| 493 | |
| 111 | 494 if (changed) |
| 145 | 495 { |
| 496 update_ssa (TODO_update_ssa); | |
| 497 /* After updating SSA form perform CSE on the loop header | |
| 498 copies. This is esp. required for the pass before | |
| 499 vectorization since nothing cleans up copied exit tests | |
| 500 that can now be simplified. CSE from the entry of the | |
| 501 region we copied till all loop exit blocks but not | |
| 502 entering the loop itself. */ | |
| 503 for (unsigned i = 0; i < copied.length (); ++i) | |
| 504 { | |
| 505 edge entry = copied[i].first; | |
| 506 loop_p loop = copied[i].second; | |
| 507 vec<edge> exit_edges = get_loop_exit_edges (loop); | |
| 508 bitmap exit_bbs = BITMAP_ALLOC (NULL); | |
| 509 for (unsigned j = 0; j < exit_edges.length (); ++j) | |
| 510 bitmap_set_bit (exit_bbs, exit_edges[j]->dest->index); | |
| 511 bitmap_set_bit (exit_bbs, loop->header->index); | |
| 512 do_rpo_vn (cfun, entry, exit_bbs); | |
| 513 BITMAP_FREE (exit_bbs); | |
| 514 exit_edges.release (); | |
| 515 } | |
| 516 } | |
| 0 | 517 free (bbs); |
| 518 free (copied_bbs); | |
| 519 | |
| 111 | 520 return changed ? TODO_cleanup_cfg : 0; |
| 521 } | |
| 522 | |
| 523 /* Initialize the loop structures we need, and finalize after. */ | |
| 524 | |
| 525 unsigned int | |
| 526 pass_ch::execute (function *fun) | |
| 527 { | |
| 528 loop_optimizer_init (LOOPS_HAVE_PREHEADERS | |
| 131 | 529 | LOOPS_HAVE_SIMPLE_LATCHES |
| 530 | LOOPS_HAVE_RECORDED_EXITS); | |
| 111 | 531 |
| 532 unsigned int res = copy_headers (fun); | |
| 533 | |
| 0 | 534 loop_optimizer_finalize (); |
| 111 | 535 return res; |
| 0 | 536 } |
| 537 | |
| 111 | 538 /* Assume an earlier phase has already initialized all the loop structures that |
| 539 we need here (and perhaps others too), and that these will be finalized by | |
| 540 a later phase. */ | |
| 541 | |
| 542 unsigned int | |
| 543 pass_ch_vect::execute (function *fun) | |
| 0 | 544 { |
| 111 | 545 return copy_headers (fun); |
| 546 } | |
| 547 | |
| 548 /* Apply header copying according to a very simple test of do-while shape. */ | |
| 549 | |
| 550 bool | |
| 145 | 551 pass_ch::process_loop_p (class loop *loop) |
| 111 | 552 { |
| 553 return !do_while_loop_p (loop); | |
| 0 | 554 } |
| 555 | |
| 111 | 556 /* Apply header-copying to loops where we might enable vectorization. */ |
| 557 | |
| 558 bool | |
| 145 | 559 pass_ch_vect::process_loop_p (class loop *loop) |
| 0 | 560 { |
| 111 | 561 if (!flag_tree_loop_vectorize && !loop->force_vectorize) |
| 562 return false; | |
| 563 | |
| 564 if (loop->dont_vectorize) | |
| 565 return false; | |
| 566 | |
| 145 | 567 /* The vectorizer won't handle anything with multiple exits, so skip. */ |
| 111 | 568 edge exit = single_exit (loop); |
| 569 if (!exit) | |
| 570 return false; | |
| 571 | |
| 145 | 572 if (!do_while_loop_p (loop)) |
| 573 return true; | |
| 111 | 574 |
| 575 return false; | |
| 576 } | |
| 577 | |
| 578 } // anon namespace | |
| 579 | |
| 580 gimple_opt_pass * | |
| 581 make_pass_ch_vect (gcc::context *ctxt) | |
| 582 { | |
| 583 return new pass_ch_vect (ctxt); | |
| 584 } | |
| 585 | |
| 586 gimple_opt_pass * | |
| 587 make_pass_ch (gcc::context *ctxt) | |
| 588 { | |
| 589 return new pass_ch (ctxt); | |
| 590 } |