gcc/gimple-walk.c

   1 /* Gimple walk support.
   2
   3    Copyright (C) 2007-2015 Free Software Foundation, Inc.
   4    Contributed by Aldy Hernandez <aldyh@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "backend.h"
  26 #include "tree.h"
  27 #include "gimple.h"
  28 #include "gimple-iterator.h"
  29 #include "gimple-walk.h"
  30 #include "stmt.h"
  31
  32 /* Walk all the statements in the sequence *PSEQ calling walk_gimple_stmt
  33    on each one.  WI is as in walk_gimple_stmt.
  34
  35    If walk_gimple_stmt returns non-NULL, the walk is stopped, and the
  36    value is stored in WI->CALLBACK_RESULT.  Also, the statement that
  37    produced the value is returned if this statement has not been
  38    removed by a callback (wi->removed_stmt).  If the statement has
  39    been removed, NULL is returned.
  40
  41    Otherwise, all the statements are walked and NULL returned.  */
  42
  43 gimple *
  44 walk_gimple_seq_mod (gimple_seq *pseq, walk_stmt_fn callback_stmt,
  45                      walk_tree_fn callback_op, struct walk_stmt_info *wi)
  46 {
  47   gimple_stmt_iterator gsi;
  48
  49   for (gsi = gsi_start (*pseq); !gsi_end_p (gsi); )
  50     {
  51       tree ret = walk_gimple_stmt (&gsi, callback_stmt, callback_op, wi);
  52       if (ret)
  53         {
  54           /* If CALLBACK_STMT or CALLBACK_OP return a value, WI must exist
  55              to hold it.  */
  56           gcc_assert (wi);
  57           wi->callback_result = ret;
  58
  59           return wi->removed_stmt ? NULL : gsi_stmt (gsi);
  60         }
  61
  62       if (!wi->removed_stmt)
  63         gsi_next (&gsi);
  64     }
  65
  66   if (wi)
  67     wi->callback_result = NULL_TREE;
  68
  69   return NULL;
  70 }
  71
  72
  73 /* Like walk_gimple_seq_mod, but ensure that the head of SEQ isn't
  74    changed by the callbacks.  */
  75
  76 gimple *
  77 walk_gimple_seq (gimple_seq seq, walk_stmt_fn callback_stmt,
  78                  walk_tree_fn callback_op, struct walk_stmt_info *wi)
  79 {
  80   gimple_seq seq2 = seq;
  81   gimple *ret = walk_gimple_seq_mod (&seq2, callback_stmt, callback_op, wi);
  82   gcc_assert (seq2 == seq);
  83   return ret;
  84 }
  85
  86
  87 /* Helper function for walk_gimple_stmt.  Walk operands of a GIMPLE_ASM.  */
  88
  89 static tree
  90 walk_gimple_asm (gasm *stmt, walk_tree_fn callback_op,
  91                  struct walk_stmt_info *wi)
  92 {
  93   tree ret, op;
  94   unsigned noutputs;
  95   const char **oconstraints;
  96   unsigned i, n;
  97   const char *constraint;
  98   bool allows_mem, allows_reg, is_inout;
  99
 100   noutputs = gimple_asm_noutputs (stmt);
 101   oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *));
 102
 103   if (wi)
 104     wi->is_lhs = true;
 105
 106   for (i = 0; i < noutputs; i++)
 107     {
 108       op = gimple_asm_output_op (stmt, i);
 109       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 110       oconstraints[i] = constraint;
 111       if (wi)
 112         {
 113           if (parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 114                                        &allows_reg, &is_inout))
 115             wi->val_only = (allows_reg || !allows_mem);
 116         }
 117       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 118       if (ret)
 119         return ret;
 120     }
 121
 122   n = gimple_asm_ninputs (stmt);
 123   for (i = 0; i < n; i++)
 124     {
 125       op = gimple_asm_input_op (stmt, i);
 126       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 127
 128       if (wi)
 129         {
 130           if (parse_input_constraint (&constraint, 0, 0, noutputs, 0,
 131                                       oconstraints, &allows_mem, &allows_reg))
 132             {
 133               wi->val_only = (allows_reg || !allows_mem);
 134               /* Although input "m" is not really a LHS, we need a lvalue.  */
 135               wi->is_lhs = !wi->val_only;
 136             }
 137         }
 138       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 139       if (ret)
 140         return ret;
 141     }
 142
 143   if (wi)
 144     {
 145       wi->is_lhs = false;
 146       wi->val_only = true;
 147     }
 148
 149   n = gimple_asm_nlabels (stmt);
 150   for (i = 0; i < n; i++)
 151     {
 152       op = gimple_asm_label_op (stmt, i);
 153       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 154       if (ret)
 155         return ret;
 156     }
 157
 158   return NULL_TREE;
 159 }
 160
 161
 162 /* Helper function of WALK_GIMPLE_STMT.  Walk every tree operand in
 163    STMT.  CALLBACK_OP and WI are as in WALK_GIMPLE_STMT.
 164
 165    CALLBACK_OP is called on each operand of STMT via walk_tree.
 166    Additional parameters to walk_tree must be stored in WI.  For each operand
 167    OP, walk_tree is called as:
 168
 169         walk_tree (&OP, CALLBACK_OP, WI, WI->PSET)
 170
 171    If CALLBACK_OP returns non-NULL for an operand, the remaining
 172    operands are not scanned.
 173
 174    The return value is that returned by the last call to walk_tree, or
 175    NULL_TREE if no CALLBACK_OP is specified.  */
 176
 177 tree
 178 walk_gimple_op (gimple *stmt, walk_tree_fn callback_op,
 179                 struct walk_stmt_info *wi)
 180 {
 181   hash_set<tree> *pset = (wi) ? wi->pset : NULL;
 182   unsigned i;
 183   tree ret = NULL_TREE;
 184
 185   switch (gimple_code (stmt))
 186     {
 187     case GIMPLE_ASSIGN:
 188       /* Walk the RHS operands.  If the LHS is of a non-renamable type or
 189          is a register variable, we may use a COMPONENT_REF on the RHS.  */
 190       if (wi)
 191         {
 192           tree lhs = gimple_assign_lhs (stmt);
 193           wi->val_only
 194             = (is_gimple_reg_type (TREE_TYPE (lhs)) && !is_gimple_reg (lhs))
 195               || gimple_assign_rhs_class (stmt) != GIMPLE_SINGLE_RHS;
 196         }
 197
 198       for (i = 1; i < gimple_num_ops (stmt); i++)
 199         {
 200           ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi,
 201                            pset);
 202           if (ret)
 203             return ret;
 204         }
 205
 206       /* Walk the LHS.  If the RHS is appropriate for a memory, we
 207          may use a COMPONENT_REF on the LHS.  */
 208       if (wi)
 209         {
 210           /* If the RHS is of a non-renamable type or is a register variable,
 211              we may use a COMPONENT_REF on the LHS.  */
 212           tree rhs1 = gimple_assign_rhs1 (stmt);
 213           wi->val_only
 214             = (is_gimple_reg_type (TREE_TYPE (rhs1)) && !is_gimple_reg (rhs1))
 215               || gimple_assign_rhs_class (stmt) != GIMPLE_SINGLE_RHS;
 216           wi->is_lhs = true;
 217         }
 218
 219       ret = walk_tree (gimple_op_ptr (stmt, 0), callback_op, wi, pset);
 220       if (ret)
 221         return ret;
 222
 223       if (wi)
 224         {
 225           wi->val_only = true;
 226           wi->is_lhs = false;
 227         }
 228       break;
 229
 230     case GIMPLE_CALL:
 231       if (wi)
 232         {
 233           wi->is_lhs = false;
 234           wi->val_only = true;
 235         }
 236
 237       ret = walk_tree (gimple_call_chain_ptr (as_a <gcall *> (stmt)),
 238                        callback_op, wi, pset);
 239       if (ret)
 240         return ret;
 241
 242       ret = walk_tree (gimple_call_fn_ptr (stmt), callback_op, wi, pset);
 243       if (ret)
 244         return ret;
 245
 246       for (i = 0; i < gimple_call_num_args (stmt); i++)
 247         {
 248           if (wi)
 249             wi->val_only
 250               = is_gimple_reg_type (TREE_TYPE (gimple_call_arg (stmt, i)));
 251           ret = walk_tree (gimple_call_arg_ptr (stmt, i), callback_op, wi,
 252                            pset);
 253           if (ret)
 254             return ret;
 255         }
 256
 257       if (gimple_call_lhs (stmt))
 258         {
 259           if (wi)
 260             {
 261               wi->is_lhs = true;
 262               wi->val_only
 263                 = is_gimple_reg_type (TREE_TYPE (gimple_call_lhs (stmt)));
 264             }
 265
 266           ret = walk_tree (gimple_call_lhs_ptr (stmt), callback_op, wi, pset);
 267           if (ret)
 268             return ret;
 269         }
 270
 271       if (wi)
 272         {
 273           wi->is_lhs = false;
 274           wi->val_only = true;
 275         }
 276       break;
 277
 278     case GIMPLE_CATCH:
 279       ret = walk_tree (gimple_catch_types_ptr (as_a <gcatch *> (stmt)),
 280                        callback_op, wi, pset);
 281       if (ret)
 282         return ret;
 283       break;
 284
 285     case GIMPLE_EH_FILTER:
 286       ret = walk_tree (gimple_eh_filter_types_ptr (stmt), callback_op, wi,
 287                        pset);
 288       if (ret)
 289         return ret;
 290       break;
 291
 292     case GIMPLE_ASM:
 293       ret = walk_gimple_asm (as_a <gasm *> (stmt), callback_op, wi);
 294       if (ret)
 295         return ret;
 296       break;
 297
 298     case GIMPLE_OMP_CONTINUE:
 299       {
 300         gomp_continue *cont_stmt = as_a <gomp_continue *> (stmt);
 301         ret = walk_tree (gimple_omp_continue_control_def_ptr (cont_stmt),
 302                          callback_op, wi, pset);
 303         if (ret)
 304           return ret;
 305
 306         ret = walk_tree (gimple_omp_continue_control_use_ptr (cont_stmt),
 307                          callback_op, wi, pset);
 308         if (ret)
 309           return ret;
 310       }
 311       break;
 312
 313     case GIMPLE_OMP_CRITICAL:
 314       {
 315         gomp_critical *omp_stmt = as_a <gomp_critical *> (stmt);
 316         ret = walk_tree (gimple_omp_critical_name_ptr (omp_stmt),
 317                          callback_op, wi, pset);
 318         if (ret)
 319           return ret;
 320         ret = walk_tree (gimple_omp_critical_clauses_ptr (omp_stmt),
 321                          callback_op, wi, pset);
 322         if (ret)
 323           return ret;
 324       }
 325       break;
 326
 327     case GIMPLE_OMP_ORDERED:
 328       {
 329         gomp_ordered *omp_stmt = as_a <gomp_ordered *> (stmt);
 330         ret = walk_tree (gimple_omp_ordered_clauses_ptr (omp_stmt),
 331                          callback_op, wi, pset);
 332         if (ret)
 333           return ret;
 334       }
 335       break;
 336
 337     case GIMPLE_OMP_FOR:
 338       ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
 339                        pset);
 340       if (ret)
 341         return ret;
 342       for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
 343         {
 344           ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
 345                            wi, pset);
 346           if (ret)
 347             return ret;
 348           ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
 349                            wi, pset);
 350           if (ret)
 351             return ret;
 352           ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
 353                            wi, pset);
 354           if (ret)
 355             return ret;
 356           ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
 357                            wi, pset);
 358           if (ret)
 359             return ret;
 360         }
 361       break;
 362
 363     case GIMPLE_OMP_PARALLEL:
 364       {
 365         gomp_parallel *omp_par_stmt = as_a <gomp_parallel *> (stmt);
 366         ret = walk_tree (gimple_omp_parallel_clauses_ptr (omp_par_stmt),
 367                          callback_op, wi, pset);
 368         if (ret)
 369           return ret;
 370         ret = walk_tree (gimple_omp_parallel_child_fn_ptr (omp_par_stmt),
 371                          callback_op, wi, pset);
 372         if (ret)
 373           return ret;
 374         ret = walk_tree (gimple_omp_parallel_data_arg_ptr (omp_par_stmt),
 375                          callback_op, wi, pset);
 376         if (ret)
 377           return ret;
 378       }
 379       break;
 380
 381     case GIMPLE_OMP_TASK:
 382       ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
 383                        wi, pset);
 384       if (ret)
 385         return ret;
 386       ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
 387                        wi, pset);
 388       if (ret)
 389         return ret;
 390       ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
 391                        wi, pset);
 392       if (ret)
 393         return ret;
 394       ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
 395                        wi, pset);
 396       if (ret)
 397         return ret;
 398       ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
 399                        wi, pset);
 400       if (ret)
 401         return ret;
 402       ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
 403                        wi, pset);
 404       if (ret)
 405         return ret;
 406       break;
 407
 408     case GIMPLE_OMP_SECTIONS:
 409       ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
 410                        wi, pset);
 411       if (ret)
 412         return ret;
 413       ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
 414                        wi, pset);
 415       if (ret)
 416         return ret;
 417
 418       break;
 419
 420     case GIMPLE_OMP_SINGLE:
 421       ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
 422                        pset);
 423       if (ret)
 424         return ret;
 425       break;
 426
 427     case GIMPLE_OMP_TARGET:
 428       {
 429         gomp_target *omp_stmt = as_a <gomp_target *> (stmt);
 430         ret = walk_tree (gimple_omp_target_clauses_ptr (omp_stmt),
 431                          callback_op, wi, pset);
 432         if (ret)
 433           return ret;
 434         ret = walk_tree (gimple_omp_target_child_fn_ptr (omp_stmt),
 435                          callback_op, wi, pset);
 436         if (ret)
 437           return ret;
 438         ret = walk_tree (gimple_omp_target_data_arg_ptr (omp_stmt),
 439                          callback_op, wi, pset);
 440         if (ret)
 441           return ret;
 442       }
 443       break;
 444
 445     case GIMPLE_OMP_TEAMS:
 446       ret = walk_tree (gimple_omp_teams_clauses_ptr (stmt), callback_op, wi,
 447                        pset);
 448       if (ret)
 449         return ret;
 450       break;
 451
 452     case GIMPLE_OMP_ATOMIC_LOAD:
 453       {
 454         gomp_atomic_load *omp_stmt = as_a <gomp_atomic_load *> (stmt);
 455         ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (omp_stmt),
 456                          callback_op, wi, pset);
 457         if (ret)
 458           return ret;
 459         ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (omp_stmt),
 460                          callback_op, wi, pset);
 461         if (ret)
 462           return ret;
 463       }
 464       break;
 465
 466     case GIMPLE_OMP_ATOMIC_STORE:
 467       {
 468         gomp_atomic_store *omp_stmt = as_a <gomp_atomic_store *> (stmt);
 469         ret = walk_tree (gimple_omp_atomic_store_val_ptr (omp_stmt),
 470                          callback_op, wi, pset);
 471         if (ret)
 472           return ret;
 473       }
 474       break;
 475
 476     case GIMPLE_TRANSACTION:
 477       ret = walk_tree (gimple_transaction_label_ptr (
 478                          as_a <gtransaction *> (stmt)),
 479                        callback_op, wi, pset);
 480       if (ret)
 481         return ret;
 482       break;
 483
 484     case GIMPLE_OMP_RETURN:
 485       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 486                        pset);
 487       if (ret)
 488         return ret;
 489       break;
 490
 491       /* Tuples that do not have operands.  */
 492     case GIMPLE_NOP:
 493     case GIMPLE_RESX:
 494     case GIMPLE_PREDICT:
 495       break;
 496
 497     default:
 498       {
 499         enum gimple_statement_structure_enum gss;
 500         gss = gimple_statement_structure (stmt);
 501         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 502           for (i = 0; i < gimple_num_ops (stmt); i++)
 503             {
 504               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 505               if (ret)
 506                 return ret;
 507             }
 508       }
 509       break;
 510     }
 511
 512   return NULL_TREE;
 513 }
 514
 515
 516 /* Walk the current statement in GSI (optionally using traversal state
 517    stored in WI).  If WI is NULL, no state is kept during traversal.
 518    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 519    that it has handled all the operands of the statement, its return
 520    value is returned.  Otherwise, the return value from CALLBACK_STMT
 521    is discarded and its operands are scanned.
 522
 523    If CALLBACK_STMT is NULL or it didn't handle the operands,
 524    CALLBACK_OP is called on each operand of the statement via
 525    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 526    operand, the remaining operands are not scanned.  In this case, the
 527    return value from CALLBACK_OP is returned.
 528
 529    In any other case, NULL_TREE is returned.  */
 530
 531 tree
 532 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 533                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 534 {
 535   gimple *ret;
 536   tree tree_ret;
 537   gimple *stmt = gsi_stmt (*gsi);
 538
 539   if (wi)
 540     {
 541       wi->gsi = *gsi;
 542       wi->removed_stmt = false;
 543
 544       if (wi->want_locations && gimple_has_location (stmt))
 545         input_location = gimple_location (stmt);
 546     }
 547
 548   ret = NULL;
 549
 550   /* Invoke the statement callback.  Return if the callback handled
 551      all of STMT operands by itself.  */
 552   if (callback_stmt)
 553     {
 554       bool handled_ops = false;
 555       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 556       if (handled_ops)
 557         return tree_ret;
 558
 559       /* If CALLBACK_STMT did not handle operands, it should not have
 560          a value to return.  */
 561       gcc_assert (tree_ret == NULL);
 562
 563       if (wi && wi->removed_stmt)
 564         return NULL;
 565
 566       /* Re-read stmt in case the callback changed it.  */
 567       stmt = gsi_stmt (*gsi);
 568     }
 569
 570   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 571   if (callback_op)
 572     {
 573       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 574       if (tree_ret)
 575         return tree_ret;
 576     }
 577
 578   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 579   switch (gimple_code (stmt))
 580     {
 581     case GIMPLE_BIND:
 582       ret = walk_gimple_seq_mod (gimple_bind_body_ptr (as_a <gbind *> (stmt)),
 583                                  callback_stmt, callback_op, wi);
 584       if (ret)
 585         return wi->callback_result;
 586       break;
 587
 588     case GIMPLE_CATCH:
 589       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (
 590                                    as_a <gcatch *> (stmt)),
 591                                  callback_stmt, callback_op, wi);
 592       if (ret)
 593         return wi->callback_result;
 594       break;
 595
 596     case GIMPLE_EH_FILTER:
 597       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 598                              callback_op, wi);
 599       if (ret)
 600         return wi->callback_result;
 601       break;
 602
 603     case GIMPLE_EH_ELSE:
 604       {
 605         geh_else *eh_else_stmt = as_a <geh_else *> (stmt);
 606         ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (eh_else_stmt),
 607                                    callback_stmt, callback_op, wi);
 608         if (ret)
 609           return wi->callback_result;
 610         ret = walk_gimple_seq_mod (gimple_eh_else_e_body_ptr (eh_else_stmt),
 611                                    callback_stmt, callback_op, wi);
 612         if (ret)
 613           return wi->callback_result;
 614       }
 615       break;
 616
 617     case GIMPLE_TRY:
 618       ret = walk_gimple_seq_mod (gimple_try_eval_ptr (stmt), callback_stmt, callback_op,
 619                              wi);
 620       if (ret)
 621         return wi->callback_result;
 622
 623       ret = walk_gimple_seq_mod (gimple_try_cleanup_ptr (stmt), callback_stmt,
 624                              callback_op, wi);
 625       if (ret)
 626         return wi->callback_result;
 627       break;
 628
 629     case GIMPLE_OMP_FOR:
 630       ret = walk_gimple_seq_mod (gimple_omp_for_pre_body_ptr (stmt), callback_stmt,
 631                              callback_op, wi);
 632       if (ret)
 633         return wi->callback_result;
 634
 635       /* FALL THROUGH.  */
 636     case GIMPLE_OMP_CRITICAL:
 637     case GIMPLE_OMP_MASTER:
 638     case GIMPLE_OMP_TASKGROUP:
 639     case GIMPLE_OMP_ORDERED:
 640     case GIMPLE_OMP_SECTION:
 641     case GIMPLE_OMP_PARALLEL:
 642     case GIMPLE_OMP_TASK:
 643     case GIMPLE_OMP_SECTIONS:
 644     case GIMPLE_OMP_SINGLE:
 645     case GIMPLE_OMP_TARGET:
 646     case GIMPLE_OMP_TEAMS:
 647       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 648                              callback_op, wi);
 649       if (ret)
 650         return wi->callback_result;
 651       break;
 652
 653     case GIMPLE_WITH_CLEANUP_EXPR:
 654       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 655                              callback_op, wi);
 656       if (ret)
 657         return wi->callback_result;
 658       break;
 659
 660     case GIMPLE_TRANSACTION:
 661       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (
 662                                    as_a <gtransaction *> (stmt)),
 663                              callback_stmt, callback_op, wi);
 664       if (ret)
 665         return wi->callback_result;
 666       break;
 667
 668     default:
 669       gcc_assert (!gimple_has_substatements (stmt));
 670       break;
 671     }
 672
 673   return NULL;
 674 }
 675
 676 /* From a tree operand OP return the base of a load or store operation
 677    or NULL_TREE if OP is not a load or a store.  */
 678
 679 static tree
 680 get_base_loadstore (tree op)
 681 {
 682   while (handled_component_p (op))
 683     op = TREE_OPERAND (op, 0);
 684   if (DECL_P (op)
 685       || INDIRECT_REF_P (op)
 686       || TREE_CODE (op) == MEM_REF
 687       || TREE_CODE (op) == TARGET_MEM_REF)
 688     return op;
 689   return NULL_TREE;
 690 }
 691
 692
 693 /* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
 694    VISIT_ADDR if non-NULL on loads, store and address-taken operands
 695    passing the STMT, the base of the operand, the operand itself containing
 696    the base and DATA to it.  The base will be either a decl, an indirect
 697    reference (including TARGET_MEM_REF) or the argument of an address
 698    expression.
 699    Returns the results of these callbacks or'ed.  */
 700
 701 bool
 702 walk_stmt_load_store_addr_ops (gimple *stmt, void *data,
 703                                walk_stmt_load_store_addr_fn visit_load,
 704                                walk_stmt_load_store_addr_fn visit_store,
 705                                walk_stmt_load_store_addr_fn visit_addr)
 706 {
 707   bool ret = false;
 708   unsigned i;
 709   if (gimple_assign_single_p (stmt))
 710     {
 711       tree lhs, rhs, arg;
 712       if (visit_store)
 713         {
 714           arg = gimple_assign_lhs (stmt);
 715           lhs = get_base_loadstore (arg);
 716           if (lhs)
 717             ret |= visit_store (stmt, lhs, arg, data);
 718         }
 719       arg = gimple_assign_rhs1 (stmt);
 720       rhs = arg;
 721       while (handled_component_p (rhs))
 722         rhs = TREE_OPERAND (rhs, 0);
 723       if (visit_addr)
 724         {
 725           if (TREE_CODE (rhs) == ADDR_EXPR)
 726             ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), arg, data);
 727           else if (TREE_CODE (rhs) == TARGET_MEM_REF
 728                    && TREE_CODE (TMR_BASE (rhs)) == ADDR_EXPR)
 729             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (rhs), 0), arg,
 730                                data);
 731           else if (TREE_CODE (rhs) == OBJ_TYPE_REF
 732                    && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
 733             ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
 734                                                    0), arg, data);
 735           else if (TREE_CODE (rhs) == CONSTRUCTOR)
 736             {
 737               unsigned int ix;
 738               tree val;
 739
 740               FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), ix, val)
 741                 if (TREE_CODE (val) == ADDR_EXPR)
 742                   ret |= visit_addr (stmt, TREE_OPERAND (val, 0), arg, data);
 743                 else if (TREE_CODE (val) == OBJ_TYPE_REF
 744                          && TREE_CODE (OBJ_TYPE_REF_OBJECT (val)) == ADDR_EXPR)
 745                   ret |= visit_addr (stmt,
 746                                      TREE_OPERAND (OBJ_TYPE_REF_OBJECT (val),
 747                                                    0), arg, data);
 748             }
 749           lhs = gimple_assign_lhs (stmt);
 750           if (TREE_CODE (lhs) == TARGET_MEM_REF
 751               && TREE_CODE (TMR_BASE (lhs)) == ADDR_EXPR)
 752             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (lhs), 0), lhs, data);
 753         }
 754       if (visit_load)
 755         {
 756           rhs = get_base_loadstore (rhs);
 757           if (rhs)
 758             ret |= visit_load (stmt, rhs, arg, data);
 759         }
 760     }
 761   else if (visit_addr
 762            && (is_gimple_assign (stmt)
 763                || gimple_code (stmt) == GIMPLE_COND))
 764     {
 765       for (i = 0; i < gimple_num_ops (stmt); ++i)
 766         {
 767           tree op = gimple_op (stmt, i);
 768           if (op == NULL_TREE)
 769             ;
 770           else if (TREE_CODE (op) == ADDR_EXPR)
 771             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 772           /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
 773              tree with two operands.  */
 774           else if (i == 1 && COMPARISON_CLASS_P (op))
 775             {
 776               if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
 777                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
 778                                                        0), op, data);
 779               if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
 780                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
 781                                                        0), op, data);
 782             }
 783         }
 784     }
 785   else if (gcall *call_stmt = dyn_cast <gcall *> (stmt))
 786     {
 787       if (visit_store)
 788         {
 789           tree arg = gimple_call_lhs (call_stmt);
 790           if (arg)
 791             {
 792               tree lhs = get_base_loadstore (arg);
 793               if (lhs)
 794                 ret |= visit_store (stmt, lhs, arg, data);
 795             }
 796         }
 797       if (visit_load || visit_addr)
 798         for (i = 0; i < gimple_call_num_args (call_stmt); ++i)
 799           {
 800             tree arg = gimple_call_arg (call_stmt, i);
 801             if (visit_addr
 802                 && TREE_CODE (arg) == ADDR_EXPR)
 803               ret |= visit_addr (stmt, TREE_OPERAND (arg, 0), arg, data);
 804             else if (visit_load)
 805               {
 806                 tree rhs = get_base_loadstore (arg);
 807                 if (rhs)
 808                   ret |= visit_load (stmt, rhs, arg, data);
 809               }
 810           }
 811       if (visit_addr
 812           && gimple_call_chain (call_stmt)
 813           && TREE_CODE (gimple_call_chain (call_stmt)) == ADDR_EXPR)
 814         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (call_stmt), 0),
 815                            gimple_call_chain (call_stmt), data);
 816       if (visit_addr
 817           && gimple_call_return_slot_opt_p (call_stmt)
 818           && gimple_call_lhs (call_stmt) != NULL_TREE
 819           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (call_stmt))))
 820         ret |= visit_addr (stmt, gimple_call_lhs (call_stmt),
 821                            gimple_call_lhs (call_stmt), data);
 822     }
 823   else if (gasm *asm_stmt = dyn_cast <gasm *> (stmt))
 824     {
 825       unsigned noutputs;
 826       const char *constraint;
 827       const char **oconstraints;
 828       bool allows_mem, allows_reg, is_inout;
 829       noutputs = gimple_asm_noutputs (asm_stmt);
 830       oconstraints = XALLOCAVEC (const char *, noutputs);
 831       if (visit_store || visit_addr)
 832         for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
 833           {
 834             tree link = gimple_asm_output_op (asm_stmt, i);
 835             tree op = get_base_loadstore (TREE_VALUE (link));
 836             if (op && visit_store)
 837               ret |= visit_store (stmt, op, TREE_VALUE (link), data);
 838             if (visit_addr)
 839               {
 840                 constraint = TREE_STRING_POINTER
 841                     (TREE_VALUE (TREE_PURPOSE (link)));
 842                 oconstraints[i] = constraint;
 843                 parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 844                                          &allows_reg, &is_inout);
 845                 if (op && !allows_reg && allows_mem)
 846                   ret |= visit_addr (stmt, op, TREE_VALUE (link), data);
 847               }
 848           }
 849       if (visit_load || visit_addr)
 850         for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
 851           {
 852             tree link = gimple_asm_input_op (asm_stmt, i);
 853             tree op = TREE_VALUE (link);
 854             if (visit_addr
 855                 && TREE_CODE (op) == ADDR_EXPR)
 856               ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 857             else if (visit_load || visit_addr)
 858               {
 859                 op = get_base_loadstore (op);
 860                 if (op)
 861                   {
 862                     if (visit_load)
 863                       ret |= visit_load (stmt, op, TREE_VALUE (link), data);
 864                     if (visit_addr)
 865                       {
 866                         constraint = TREE_STRING_POINTER
 867                             (TREE_VALUE (TREE_PURPOSE (link)));
 868                         parse_input_constraint (&constraint, 0, 0, noutputs,
 869                                                 0, oconstraints,
 870                                                 &allows_mem, &allows_reg);
 871                         if (!allows_reg && allows_mem)
 872                           ret |= visit_addr (stmt, op, TREE_VALUE (link),
 873                                              data);
 874                       }
 875                   }
 876               }
 877           }
 878     }
 879   else if (greturn *return_stmt = dyn_cast <greturn *> (stmt))
 880     {
 881       tree op = gimple_return_retval (return_stmt);
 882       if (op)
 883         {
 884           if (visit_addr
 885               && TREE_CODE (op) == ADDR_EXPR)
 886             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 887           else if (visit_load)
 888             {
 889               tree base = get_base_loadstore (op);
 890               if (base)
 891                 ret |= visit_load (stmt, base, op, data);
 892             }
 893         }
 894     }
 895   else if (visit_addr
 896            && gimple_code (stmt) == GIMPLE_PHI)
 897     {
 898       for (i = 0; i < gimple_phi_num_args (stmt); ++i)
 899         {
 900           tree op = gimple_phi_arg_def (stmt, i);
 901           if (TREE_CODE (op) == ADDR_EXPR)
 902             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 903         }
 904     }
 905   else if (visit_addr
 906            && gimple_code (stmt) == GIMPLE_GOTO)
 907     {
 908       tree op = gimple_goto_dest (stmt);
 909       if (TREE_CODE (op) == ADDR_EXPR)
 910         ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 911     }
 912
 913   return ret;
 914 }
 915
 916 /* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
 917    should make a faster clone for this case.  */
 918
 919 bool
 920 walk_stmt_load_store_ops (gimple *stmt, void *data,
 921                           walk_stmt_load_store_addr_fn visit_load,
 922                           walk_stmt_load_store_addr_fn visit_store)
 923 {
 924   return walk_stmt_load_store_addr_ops (stmt, data,
 925                                         visit_load, visit_store, NULL);
 926 }