gcc/gimple-walk.c

   1 /* Gimple walk support.
   2
   3    Copyright (C) 2007-2018 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   for (i = 0; i < noutputs; i++)
 104     {
 105       op = gimple_asm_output_op (stmt, i);
 106       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 107       oconstraints[i] = constraint;
 108       if (wi)
 109         {
 110           if (parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 111                                        &allows_reg, &is_inout))
 112             wi->val_only = (allows_reg || !allows_mem);
 113         }
 114       if (wi)
 115         wi->is_lhs = true;
 116       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 117       if (ret)
 118         return ret;
 119     }
 120
 121   n = gimple_asm_ninputs (stmt);
 122   for (i = 0; i < n; i++)
 123     {
 124       op = gimple_asm_input_op (stmt, i);
 125       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 126
 127       if (wi)
 128         {
 129           if (parse_input_constraint (&constraint, 0, 0, noutputs, 0,
 130                                       oconstraints, &allows_mem, &allows_reg))
 131             {
 132               wi->val_only = (allows_reg || !allows_mem);
 133               /* Although input "m" is not really a LHS, we need a lvalue.  */
 134               wi->is_lhs = !wi->val_only;
 135             }
 136         }
 137       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 138       if (ret)
 139         return ret;
 140     }
 141
 142   if (wi)
 143     {
 144       wi->is_lhs = false;
 145       wi->val_only = true;
 146     }
 147
 148   n = gimple_asm_nlabels (stmt);
 149   for (i = 0; i < n; i++)
 150     {
 151       op = gimple_asm_label_op (stmt, i);
 152       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 153       if (ret)
 154         return ret;
 155     }
 156
 157   return NULL_TREE;
 158 }
 159
 160
 161 /* Helper function of WALK_GIMPLE_STMT.  Walk every tree operand in
 162    STMT.  CALLBACK_OP and WI are as in WALK_GIMPLE_STMT.
 163
 164    CALLBACK_OP is called on each operand of STMT via walk_tree.
 165    Additional parameters to walk_tree must be stored in WI.  For each operand
 166    OP, walk_tree is called as:
 167
 168         walk_tree (&OP, CALLBACK_OP, WI, WI->PSET)
 169
 170    If CALLBACK_OP returns non-NULL for an operand, the remaining
 171    operands are not scanned.
 172
 173    The return value is that returned by the last call to walk_tree, or
 174    NULL_TREE if no CALLBACK_OP is specified.  */
 175
 176 tree
 177 walk_gimple_op (gimple *stmt, walk_tree_fn callback_op,
 178                 struct walk_stmt_info *wi)
 179 {
 180   hash_set<tree> *pset = (wi) ? wi->pset : NULL;
 181   unsigned i;
 182   tree ret = NULL_TREE;
 183
 184   if (wi)
 185     wi->stmt = stmt;
 186
 187   switch (gimple_code (stmt))
 188     {
 189     case GIMPLE_ASSIGN:
 190       /* Walk the RHS operands.  If the LHS is of a non-renamable type or
 191          is a register variable, we may use a COMPONENT_REF on the RHS.  */
 192       if (wi)
 193         {
 194           tree lhs = gimple_assign_lhs (stmt);
 195           wi->val_only
 196             = (is_gimple_reg_type (TREE_TYPE (lhs)) && !is_gimple_reg (lhs))
 197               || gimple_assign_rhs_class (stmt) != GIMPLE_SINGLE_RHS;
 198         }
 199
 200       for (i = 1; i < gimple_num_ops (stmt); i++)
 201         {
 202           ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi,
 203                            pset);
 204           if (ret)
 205             return ret;
 206         }
 207
 208       /* Walk the LHS.  If the RHS is appropriate for a memory, we
 209          may use a COMPONENT_REF on the LHS.  */
 210       if (wi)
 211         {
 212           /* If the RHS is of a non-renamable type or is a register variable,
 213              we may use a COMPONENT_REF on the LHS.  */
 214           tree rhs1 = gimple_assign_rhs1 (stmt);
 215           wi->val_only
 216             = (is_gimple_reg_type (TREE_TYPE (rhs1)) && !is_gimple_reg (rhs1))
 217               || gimple_assign_rhs_class (stmt) != GIMPLE_SINGLE_RHS;
 218           wi->is_lhs = true;
 219         }
 220
 221       ret = walk_tree (gimple_op_ptr (stmt, 0), callback_op, wi, pset);
 222       if (ret)
 223         return ret;
 224
 225       if (wi)
 226         {
 227           wi->val_only = true;
 228           wi->is_lhs = false;
 229         }
 230       break;
 231
 232     case GIMPLE_CALL:
 233       if (wi)
 234         {
 235           wi->is_lhs = false;
 236           wi->val_only = true;
 237         }
 238
 239       ret = walk_tree (gimple_call_chain_ptr (as_a <gcall *> (stmt)),
 240                        callback_op, wi, pset);
 241       if (ret)
 242         return ret;
 243
 244       ret = walk_tree (gimple_call_fn_ptr (stmt), callback_op, wi, pset);
 245       if (ret)
 246         return ret;
 247
 248       for (i = 0; i < gimple_call_num_args (stmt); i++)
 249         {
 250           if (wi)
 251             wi->val_only
 252               = is_gimple_reg_type (TREE_TYPE (gimple_call_arg (stmt, i)));
 253           ret = walk_tree (gimple_call_arg_ptr (stmt, i), callback_op, wi,
 254                            pset);
 255           if (ret)
 256             return ret;
 257         }
 258
 259       if (gimple_call_lhs (stmt))
 260         {
 261           if (wi)
 262             {
 263               wi->is_lhs = true;
 264               wi->val_only
 265                 = is_gimple_reg_type (TREE_TYPE (gimple_call_lhs (stmt)));
 266             }
 267
 268           ret = walk_tree (gimple_call_lhs_ptr (stmt), callback_op, wi, pset);
 269           if (ret)
 270             return ret;
 271         }
 272
 273       if (wi)
 274         {
 275           wi->is_lhs = false;
 276           wi->val_only = true;
 277         }
 278       break;
 279
 280     case GIMPLE_CATCH:
 281       ret = walk_tree (gimple_catch_types_ptr (as_a <gcatch *> (stmt)),
 282                        callback_op, wi, pset);
 283       if (ret)
 284         return ret;
 285       break;
 286
 287     case GIMPLE_EH_FILTER:
 288       ret = walk_tree (gimple_eh_filter_types_ptr (stmt), callback_op, wi,
 289                        pset);
 290       if (ret)
 291         return ret;
 292       break;
 293
 294     case GIMPLE_ASM:
 295       ret = walk_gimple_asm (as_a <gasm *> (stmt), callback_op, wi);
 296       if (ret)
 297         return ret;
 298       break;
 299
 300     case GIMPLE_OMP_CONTINUE:
 301       {
 302         gomp_continue *cont_stmt = as_a <gomp_continue *> (stmt);
 303         ret = walk_tree (gimple_omp_continue_control_def_ptr (cont_stmt),
 304                          callback_op, wi, pset);
 305         if (ret)
 306           return ret;
 307
 308         ret = walk_tree (gimple_omp_continue_control_use_ptr (cont_stmt),
 309                          callback_op, wi, pset);
 310         if (ret)
 311           return ret;
 312       }
 313       break;
 314
 315     case GIMPLE_OMP_CRITICAL:
 316       {
 317         gomp_critical *omp_stmt = as_a <gomp_critical *> (stmt);
 318         ret = walk_tree (gimple_omp_critical_name_ptr (omp_stmt),
 319                          callback_op, wi, pset);
 320         if (ret)
 321           return ret;
 322         ret = walk_tree (gimple_omp_critical_clauses_ptr (omp_stmt),
 323                          callback_op, wi, pset);
 324         if (ret)
 325           return ret;
 326       }
 327       break;
 328
 329     case GIMPLE_OMP_ORDERED:
 330       {
 331         gomp_ordered *omp_stmt = as_a <gomp_ordered *> (stmt);
 332         ret = walk_tree (gimple_omp_ordered_clauses_ptr (omp_stmt),
 333                          callback_op, wi, pset);
 334         if (ret)
 335           return ret;
 336       }
 337       break;
 338
 339     case GIMPLE_OMP_FOR:
 340       ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
 341                        pset);
 342       if (ret)
 343         return ret;
 344       for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
 345         {
 346           ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
 347                            wi, pset);
 348           if (ret)
 349             return ret;
 350           ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
 351                            wi, pset);
 352           if (ret)
 353             return ret;
 354           ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
 355                            wi, pset);
 356           if (ret)
 357             return ret;
 358           ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
 359                            wi, pset);
 360           if (ret)
 361             return ret;
 362         }
 363       break;
 364
 365     case GIMPLE_OMP_PARALLEL:
 366       {
 367         gomp_parallel *omp_par_stmt = as_a <gomp_parallel *> (stmt);
 368         ret = walk_tree (gimple_omp_parallel_clauses_ptr (omp_par_stmt),
 369                          callback_op, wi, pset);
 370         if (ret)
 371           return ret;
 372         ret = walk_tree (gimple_omp_parallel_child_fn_ptr (omp_par_stmt),
 373                          callback_op, wi, pset);
 374         if (ret)
 375           return ret;
 376         ret = walk_tree (gimple_omp_parallel_data_arg_ptr (omp_par_stmt),
 377                          callback_op, wi, pset);
 378         if (ret)
 379           return ret;
 380       }
 381       break;
 382
 383     case GIMPLE_OMP_TASK:
 384       ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
 385                        wi, pset);
 386       if (ret)
 387         return ret;
 388       ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
 389                        wi, pset);
 390       if (ret)
 391         return ret;
 392       ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
 393                        wi, pset);
 394       if (ret)
 395         return ret;
 396       ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
 397                        wi, pset);
 398       if (ret)
 399         return ret;
 400       ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
 401                        wi, pset);
 402       if (ret)
 403         return ret;
 404       ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
 405                        wi, pset);
 406       if (ret)
 407         return ret;
 408       break;
 409
 410     case GIMPLE_OMP_SECTIONS:
 411       ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
 412                        wi, pset);
 413       if (ret)
 414         return ret;
 415       ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
 416                        wi, pset);
 417       if (ret)
 418         return ret;
 419
 420       break;
 421
 422     case GIMPLE_OMP_SINGLE:
 423       ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
 424                        pset);
 425       if (ret)
 426         return ret;
 427       break;
 428
 429     case GIMPLE_OMP_TARGET:
 430       {
 431         gomp_target *omp_stmt = as_a <gomp_target *> (stmt);
 432         ret = walk_tree (gimple_omp_target_clauses_ptr (omp_stmt),
 433                          callback_op, wi, pset);
 434         if (ret)
 435           return ret;
 436         ret = walk_tree (gimple_omp_target_child_fn_ptr (omp_stmt),
 437                          callback_op, wi, pset);
 438         if (ret)
 439           return ret;
 440         ret = walk_tree (gimple_omp_target_data_arg_ptr (omp_stmt),
 441                          callback_op, wi, pset);
 442         if (ret)
 443           return ret;
 444       }
 445       break;
 446
 447     case GIMPLE_OMP_TEAMS:
 448       ret = walk_tree (gimple_omp_teams_clauses_ptr (stmt), callback_op, wi,
 449                        pset);
 450       if (ret)
 451         return ret;
 452       break;
 453
 454     case GIMPLE_OMP_ATOMIC_LOAD:
 455       {
 456         gomp_atomic_load *omp_stmt = as_a <gomp_atomic_load *> (stmt);
 457         ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (omp_stmt),
 458                          callback_op, wi, pset);
 459         if (ret)
 460           return ret;
 461         ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (omp_stmt),
 462                          callback_op, wi, pset);
 463         if (ret)
 464           return ret;
 465       }
 466       break;
 467
 468     case GIMPLE_OMP_ATOMIC_STORE:
 469       {
 470         gomp_atomic_store *omp_stmt = as_a <gomp_atomic_store *> (stmt);
 471         ret = walk_tree (gimple_omp_atomic_store_val_ptr (omp_stmt),
 472                          callback_op, wi, pset);
 473         if (ret)
 474           return ret;
 475       }
 476       break;
 477
 478     case GIMPLE_TRANSACTION:
 479       {
 480         gtransaction *txn = as_a <gtransaction *> (stmt);
 481
 482         ret = walk_tree (gimple_transaction_label_norm_ptr (txn),
 483                          callback_op, wi, pset);
 484         if (ret)
 485           return ret;
 486         ret = walk_tree (gimple_transaction_label_uninst_ptr (txn),
 487                          callback_op, wi, pset);
 488         if (ret)
 489           return ret;
 490         ret = walk_tree (gimple_transaction_label_over_ptr (txn),
 491                          callback_op, wi, pset);
 492         if (ret)
 493           return ret;
 494       }
 495       break;
 496
 497     case GIMPLE_OMP_RETURN:
 498       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 499                        pset);
 500       if (ret)
 501         return ret;
 502       break;
 503
 504       /* Tuples that do not have operands.  */
 505     case GIMPLE_NOP:
 506     case GIMPLE_RESX:
 507     case GIMPLE_PREDICT:
 508       break;
 509
 510     default:
 511       {
 512         enum gimple_statement_structure_enum gss;
 513         gss = gimple_statement_structure (stmt);
 514         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 515           for (i = 0; i < gimple_num_ops (stmt); i++)
 516             {
 517               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 518               if (ret)
 519                 return ret;
 520             }
 521       }
 522       break;
 523     }
 524
 525   return NULL_TREE;
 526 }
 527
 528
 529 /* Walk the current statement in GSI (optionally using traversal state
 530    stored in WI).  If WI is NULL, no state is kept during traversal.
 531    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 532    that it has handled all the operands of the statement, its return
 533    value is returned.  Otherwise, the return value from CALLBACK_STMT
 534    is discarded and its operands are scanned.
 535
 536    If CALLBACK_STMT is NULL or it didn't handle the operands,
 537    CALLBACK_OP is called on each operand of the statement via
 538    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 539    operand, the remaining operands are not scanned.  In this case, the
 540    return value from CALLBACK_OP is returned.
 541
 542    In any other case, NULL_TREE is returned.  */
 543
 544 tree
 545 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 546                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 547 {
 548   gimple *ret;
 549   tree tree_ret;
 550   gimple *stmt = gsi_stmt (*gsi);
 551
 552   if (wi)
 553     {
 554       wi->gsi = *gsi;
 555       wi->removed_stmt = false;
 556
 557       if (wi->want_locations && gimple_has_location (stmt))
 558         input_location = gimple_location (stmt);
 559     }
 560
 561   ret = NULL;
 562
 563   /* Invoke the statement callback.  Return if the callback handled
 564      all of STMT operands by itself.  */
 565   if (callback_stmt)
 566     {
 567       bool handled_ops = false;
 568       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 569       if (handled_ops)
 570         return tree_ret;
 571
 572       /* If CALLBACK_STMT did not handle operands, it should not have
 573          a value to return.  */
 574       gcc_assert (tree_ret == NULL);
 575
 576       if (wi && wi->removed_stmt)
 577         return NULL;
 578
 579       /* Re-read stmt in case the callback changed it.  */
 580       stmt = gsi_stmt (*gsi);
 581     }
 582
 583   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 584   if (callback_op)
 585     {
 586       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 587       if (tree_ret)
 588         return tree_ret;
 589     }
 590
 591   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 592   switch (gimple_code (stmt))
 593     {
 594     case GIMPLE_BIND:
 595       ret = walk_gimple_seq_mod (gimple_bind_body_ptr (as_a <gbind *> (stmt)),
 596                                  callback_stmt, callback_op, wi);
 597       if (ret)
 598         return wi->callback_result;
 599       break;
 600
 601     case GIMPLE_CATCH:
 602       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (
 603                                    as_a <gcatch *> (stmt)),
 604                                  callback_stmt, callback_op, wi);
 605       if (ret)
 606         return wi->callback_result;
 607       break;
 608
 609     case GIMPLE_EH_FILTER:
 610       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 611                              callback_op, wi);
 612       if (ret)
 613         return wi->callback_result;
 614       break;
 615
 616     case GIMPLE_EH_ELSE:
 617       {
 618         geh_else *eh_else_stmt = as_a <geh_else *> (stmt);
 619         ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (eh_else_stmt),
 620                                    callback_stmt, callback_op, wi);
 621         if (ret)
 622           return wi->callback_result;
 623         ret = walk_gimple_seq_mod (gimple_eh_else_e_body_ptr (eh_else_stmt),
 624                                    callback_stmt, callback_op, wi);
 625         if (ret)
 626           return wi->callback_result;
 627       }
 628       break;
 629
 630     case GIMPLE_TRY:
 631       ret = walk_gimple_seq_mod (gimple_try_eval_ptr (stmt), callback_stmt, callback_op,
 632                              wi);
 633       if (ret)
 634         return wi->callback_result;
 635
 636       ret = walk_gimple_seq_mod (gimple_try_cleanup_ptr (stmt), callback_stmt,
 637                              callback_op, wi);
 638       if (ret)
 639         return wi->callback_result;
 640       break;
 641
 642     case GIMPLE_OMP_FOR:
 643       ret = walk_gimple_seq_mod (gimple_omp_for_pre_body_ptr (stmt), callback_stmt,
 644                              callback_op, wi);
 645       if (ret)
 646         return wi->callback_result;
 647
 648       /* FALL THROUGH.  */
 649     case GIMPLE_OMP_CRITICAL:
 650     case GIMPLE_OMP_MASTER:
 651     case GIMPLE_OMP_TASKGROUP:
 652     case GIMPLE_OMP_ORDERED:
 653     case GIMPLE_OMP_SECTION:
 654     case GIMPLE_OMP_PARALLEL:
 655     case GIMPLE_OMP_TASK:
 656     case GIMPLE_OMP_SECTIONS:
 657     case GIMPLE_OMP_SINGLE:
 658     case GIMPLE_OMP_TARGET:
 659     case GIMPLE_OMP_TEAMS:
 660     case GIMPLE_OMP_GRID_BODY:
 661       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 662                              callback_op, wi);
 663       if (ret)
 664         return wi->callback_result;
 665       break;
 666
 667     case GIMPLE_WITH_CLEANUP_EXPR:
 668       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 669                              callback_op, wi);
 670       if (ret)
 671         return wi->callback_result;
 672       break;
 673
 674     case GIMPLE_TRANSACTION:
 675       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (
 676                                    as_a <gtransaction *> (stmt)),
 677                              callback_stmt, callback_op, wi);
 678       if (ret)
 679         return wi->callback_result;
 680       break;
 681
 682     default:
 683       gcc_assert (!gimple_has_substatements (stmt));
 684       break;
 685     }
 686
 687   return NULL;
 688 }
 689
 690 /* From a tree operand OP return the base of a load or store operation
 691    or NULL_TREE if OP is not a load or a store.  */
 692
 693 static tree
 694 get_base_loadstore (tree op)
 695 {
 696   while (handled_component_p (op))
 697     op = TREE_OPERAND (op, 0);
 698   if (DECL_P (op)
 699       || INDIRECT_REF_P (op)
 700       || TREE_CODE (op) == MEM_REF
 701       || TREE_CODE (op) == TARGET_MEM_REF)
 702     return op;
 703   return NULL_TREE;
 704 }
 705
 706
 707 /* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
 708    VISIT_ADDR if non-NULL on loads, store and address-taken operands
 709    passing the STMT, the base of the operand, the operand itself containing
 710    the base and DATA to it.  The base will be either a decl, an indirect
 711    reference (including TARGET_MEM_REF) or the argument of an address
 712    expression.
 713    Returns the results of these callbacks or'ed.  */
 714
 715 bool
 716 walk_stmt_load_store_addr_ops (gimple *stmt, void *data,
 717                                walk_stmt_load_store_addr_fn visit_load,
 718                                walk_stmt_load_store_addr_fn visit_store,
 719                                walk_stmt_load_store_addr_fn visit_addr)
 720 {
 721   bool ret = false;
 722   unsigned i;
 723   if (gimple_assign_single_p (stmt))
 724     {
 725       tree lhs, rhs, arg;
 726       if (visit_store)
 727         {
 728           arg = gimple_assign_lhs (stmt);
 729           lhs = get_base_loadstore (arg);
 730           if (lhs)
 731             ret |= visit_store (stmt, lhs, arg, data);
 732         }
 733       arg = gimple_assign_rhs1 (stmt);
 734       rhs = arg;
 735       while (handled_component_p (rhs))
 736         rhs = TREE_OPERAND (rhs, 0);
 737       if (visit_addr)
 738         {
 739           if (TREE_CODE (rhs) == ADDR_EXPR)
 740             ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), arg, data);
 741           else if (TREE_CODE (rhs) == TARGET_MEM_REF
 742                    && TREE_CODE (TMR_BASE (rhs)) == ADDR_EXPR)
 743             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (rhs), 0), arg,
 744                                data);
 745           else if (TREE_CODE (rhs) == OBJ_TYPE_REF
 746                    && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
 747             ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
 748                                                    0), arg, data);
 749           else if (TREE_CODE (rhs) == CONSTRUCTOR)
 750             {
 751               unsigned int ix;
 752               tree val;
 753
 754               FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), ix, val)
 755                 if (TREE_CODE (val) == ADDR_EXPR)
 756                   ret |= visit_addr (stmt, TREE_OPERAND (val, 0), arg, data);
 757                 else if (TREE_CODE (val) == OBJ_TYPE_REF
 758                          && TREE_CODE (OBJ_TYPE_REF_OBJECT (val)) == ADDR_EXPR)
 759                   ret |= visit_addr (stmt,
 760                                      TREE_OPERAND (OBJ_TYPE_REF_OBJECT (val),
 761                                                    0), arg, data);
 762             }
 763           lhs = gimple_assign_lhs (stmt);
 764           if (TREE_CODE (lhs) == TARGET_MEM_REF
 765               && TREE_CODE (TMR_BASE (lhs)) == ADDR_EXPR)
 766             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (lhs), 0), lhs, data);
 767         }
 768       if (visit_load)
 769         {
 770           rhs = get_base_loadstore (rhs);
 771           if (rhs)
 772             ret |= visit_load (stmt, rhs, arg, data);
 773         }
 774     }
 775   else if (visit_addr
 776            && (is_gimple_assign (stmt)
 777                || gimple_code (stmt) == GIMPLE_COND))
 778     {
 779       for (i = 0; i < gimple_num_ops (stmt); ++i)
 780         {
 781           tree op = gimple_op (stmt, i);
 782           if (op == NULL_TREE)
 783             ;
 784           else if (TREE_CODE (op) == ADDR_EXPR)
 785             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 786           /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
 787              tree with two operands.  */
 788           else if (i == 1 && COMPARISON_CLASS_P (op))
 789             {
 790               if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
 791                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
 792                                                        0), op, data);
 793               if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
 794                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
 795                                                        0), op, data);
 796             }
 797         }
 798     }
 799   else if (gcall *call_stmt = dyn_cast <gcall *> (stmt))
 800     {
 801       if (visit_store)
 802         {
 803           tree arg = gimple_call_lhs (call_stmt);
 804           if (arg)
 805             {
 806               tree lhs = get_base_loadstore (arg);
 807               if (lhs)
 808                 ret |= visit_store (stmt, lhs, arg, data);
 809             }
 810         }
 811       if (visit_load || visit_addr)
 812         for (i = 0; i < gimple_call_num_args (call_stmt); ++i)
 813           {
 814             tree arg = gimple_call_arg (call_stmt, i);
 815             if (visit_addr
 816                 && TREE_CODE (arg) == ADDR_EXPR)
 817               ret |= visit_addr (stmt, TREE_OPERAND (arg, 0), arg, data);
 818             else if (visit_load)
 819               {
 820                 tree rhs = get_base_loadstore (arg);
 821                 if (rhs)
 822                   ret |= visit_load (stmt, rhs, arg, data);
 823               }
 824           }
 825       if (visit_addr
 826           && gimple_call_chain (call_stmt)
 827           && TREE_CODE (gimple_call_chain (call_stmt)) == ADDR_EXPR)
 828         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (call_stmt), 0),
 829                            gimple_call_chain (call_stmt), data);
 830       if (visit_addr
 831           && gimple_call_return_slot_opt_p (call_stmt)
 832           && gimple_call_lhs (call_stmt) != NULL_TREE
 833           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (call_stmt))))
 834         ret |= visit_addr (stmt, gimple_call_lhs (call_stmt),
 835                            gimple_call_lhs (call_stmt), data);
 836     }
 837   else if (gasm *asm_stmt = dyn_cast <gasm *> (stmt))
 838     {
 839       unsigned noutputs;
 840       const char *constraint;
 841       const char **oconstraints;
 842       bool allows_mem, allows_reg, is_inout;
 843       noutputs = gimple_asm_noutputs (asm_stmt);
 844       oconstraints = XALLOCAVEC (const char *, noutputs);
 845       if (visit_store || visit_addr)
 846         for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
 847           {
 848             tree link = gimple_asm_output_op (asm_stmt, i);
 849             tree op = get_base_loadstore (TREE_VALUE (link));
 850             if (op && visit_store)
 851               ret |= visit_store (stmt, op, TREE_VALUE (link), data);
 852             if (visit_addr)
 853               {
 854                 constraint = TREE_STRING_POINTER
 855                     (TREE_VALUE (TREE_PURPOSE (link)));
 856                 oconstraints[i] = constraint;
 857                 parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 858                                          &allows_reg, &is_inout);
 859                 if (op && !allows_reg && allows_mem)
 860                   ret |= visit_addr (stmt, op, TREE_VALUE (link), data);
 861               }
 862           }
 863       if (visit_load || visit_addr)
 864         for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
 865           {
 866             tree link = gimple_asm_input_op (asm_stmt, i);
 867             tree op = TREE_VALUE (link);
 868             if (visit_addr
 869                 && TREE_CODE (op) == ADDR_EXPR)
 870               ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 871             else if (visit_load || visit_addr)
 872               {
 873                 op = get_base_loadstore (op);
 874                 if (op)
 875                   {
 876                     if (visit_load)
 877                       ret |= visit_load (stmt, op, TREE_VALUE (link), data);
 878                     if (visit_addr)
 879                       {
 880                         constraint = TREE_STRING_POINTER
 881                             (TREE_VALUE (TREE_PURPOSE (link)));
 882                         parse_input_constraint (&constraint, 0, 0, noutputs,
 883                                                 0, oconstraints,
 884                                                 &allows_mem, &allows_reg);
 885                         if (!allows_reg && allows_mem)
 886                           ret |= visit_addr (stmt, op, TREE_VALUE (link),
 887                                              data);
 888                       }
 889                   }
 890               }
 891           }
 892     }
 893   else if (greturn *return_stmt = dyn_cast <greturn *> (stmt))
 894     {
 895       tree op = gimple_return_retval (return_stmt);
 896       if (op)
 897         {
 898           if (visit_addr
 899               && TREE_CODE (op) == ADDR_EXPR)
 900             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 901           else if (visit_load)
 902             {
 903               tree base = get_base_loadstore (op);
 904               if (base)
 905                 ret |= visit_load (stmt, base, op, data);
 906             }
 907         }
 908     }
 909   else if (visit_addr
 910            && gimple_code (stmt) == GIMPLE_PHI)
 911     {
 912       for (i = 0; i < gimple_phi_num_args (stmt); ++i)
 913         {
 914           tree op = gimple_phi_arg_def (stmt, i);
 915           if (TREE_CODE (op) == ADDR_EXPR)
 916             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 917         }
 918     }
 919   else if (visit_addr
 920            && gimple_code (stmt) == GIMPLE_GOTO)
 921     {
 922       tree op = gimple_goto_dest (stmt);
 923       if (TREE_CODE (op) == ADDR_EXPR)
 924         ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 925     }
 926
 927   return ret;
 928 }
 929
 930 /* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
 931    should make a faster clone for this case.  */
 932
 933 bool
 934 walk_stmt_load_store_ops (gimple *stmt, void *data,
 935                           walk_stmt_load_store_addr_fn visit_load,
 936                           walk_stmt_load_store_addr_fn visit_store)
 937 {
 938   return walk_stmt_load_store_addr_ops (stmt, data,
 939                                         visit_load, visit_store, NULL);
 940 }