gcc/gimple-walk.cc

   1 /* Gimple walk support.
   2
   3    Copyright (C) 2007-2022 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_SCAN:
 340       {
 341         gomp_scan *scan_stmt = as_a <gomp_scan *> (stmt);
 342         ret = walk_tree (gimple_omp_scan_clauses_ptr (scan_stmt),
 343                          callback_op, wi, pset);
 344         if (ret)
 345           return ret;
 346       }
 347       break;
 348
 349     case GIMPLE_OMP_FOR:
 350       ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
 351                        pset);
 352       if (ret)
 353         return ret;
 354       for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
 355         {
 356           ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
 357                            wi, pset);
 358           if (ret)
 359             return ret;
 360           ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
 361                            wi, pset);
 362           if (ret)
 363             return ret;
 364           ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
 365                            wi, pset);
 366           if (ret)
 367             return ret;
 368           ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
 369                            wi, pset);
 370           if (ret)
 371             return ret;
 372         }
 373       break;
 374
 375     case GIMPLE_OMP_PARALLEL:
 376       {
 377         gomp_parallel *omp_par_stmt = as_a <gomp_parallel *> (stmt);
 378         ret = walk_tree (gimple_omp_parallel_clauses_ptr (omp_par_stmt),
 379                          callback_op, wi, pset);
 380         if (ret)
 381           return ret;
 382         ret = walk_tree (gimple_omp_parallel_child_fn_ptr (omp_par_stmt),
 383                          callback_op, wi, pset);
 384         if (ret)
 385           return ret;
 386         ret = walk_tree (gimple_omp_parallel_data_arg_ptr (omp_par_stmt),
 387                          callback_op, wi, pset);
 388         if (ret)
 389           return ret;
 390       }
 391       break;
 392
 393     case GIMPLE_OMP_TASK:
 394       ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
 395                        wi, pset);
 396       if (ret)
 397         return ret;
 398       ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
 399                        wi, pset);
 400       if (ret)
 401         return ret;
 402       ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
 403                        wi, pset);
 404       if (ret)
 405         return ret;
 406       ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
 407                        wi, pset);
 408       if (ret)
 409         return ret;
 410       ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
 411                        wi, pset);
 412       if (ret)
 413         return ret;
 414       ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
 415                        wi, pset);
 416       if (ret)
 417         return ret;
 418       break;
 419
 420     case GIMPLE_OMP_SECTIONS:
 421       ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
 422                        wi, pset);
 423       if (ret)
 424         return ret;
 425       ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
 426                        wi, pset);
 427       if (ret)
 428         return ret;
 429
 430       break;
 431
 432     case GIMPLE_OMP_SINGLE:
 433       ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
 434                        pset);
 435       if (ret)
 436         return ret;
 437       break;
 438
 439     case GIMPLE_OMP_TARGET:
 440       {
 441         gomp_target *omp_stmt = as_a <gomp_target *> (stmt);
 442         ret = walk_tree (gimple_omp_target_clauses_ptr (omp_stmt),
 443                          callback_op, wi, pset);
 444         if (ret)
 445           return ret;
 446         ret = walk_tree (gimple_omp_target_child_fn_ptr (omp_stmt),
 447                          callback_op, wi, pset);
 448         if (ret)
 449           return ret;
 450         ret = walk_tree (gimple_omp_target_data_arg_ptr (omp_stmt),
 451                          callback_op, wi, pset);
 452         if (ret)
 453           return ret;
 454       }
 455       break;
 456
 457     case GIMPLE_OMP_TEAMS:
 458       ret = walk_tree (gimple_omp_teams_clauses_ptr (stmt), callback_op, wi,
 459                        pset);
 460       if (ret)
 461         return ret;
 462       break;
 463
 464     case GIMPLE_OMP_ATOMIC_LOAD:
 465       {
 466         gomp_atomic_load *omp_stmt = as_a <gomp_atomic_load *> (stmt);
 467         ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (omp_stmt),
 468                          callback_op, wi, pset);
 469         if (ret)
 470           return ret;
 471         ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (omp_stmt),
 472                          callback_op, wi, pset);
 473         if (ret)
 474           return ret;
 475       }
 476       break;
 477
 478     case GIMPLE_OMP_ATOMIC_STORE:
 479       {
 480         gomp_atomic_store *omp_stmt = as_a <gomp_atomic_store *> (stmt);
 481         ret = walk_tree (gimple_omp_atomic_store_val_ptr (omp_stmt),
 482                          callback_op, wi, pset);
 483         if (ret)
 484           return ret;
 485       }
 486       break;
 487
 488     case GIMPLE_TRANSACTION:
 489       {
 490         gtransaction *txn = as_a <gtransaction *> (stmt);
 491
 492         ret = walk_tree (gimple_transaction_label_norm_ptr (txn),
 493                          callback_op, wi, pset);
 494         if (ret)
 495           return ret;
 496         ret = walk_tree (gimple_transaction_label_uninst_ptr (txn),
 497                          callback_op, wi, pset);
 498         if (ret)
 499           return ret;
 500         ret = walk_tree (gimple_transaction_label_over_ptr (txn),
 501                          callback_op, wi, pset);
 502         if (ret)
 503           return ret;
 504       }
 505       break;
 506
 507     case GIMPLE_OMP_RETURN:
 508       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 509                        pset);
 510       if (ret)
 511         return ret;
 512       break;
 513
 514       /* Tuples that do not have operands.  */
 515     case GIMPLE_NOP:
 516     case GIMPLE_RESX:
 517     case GIMPLE_PREDICT:
 518       break;
 519
 520     case GIMPLE_PHI:
 521       /* PHIs are not GSS_WITH_OPS so we need to handle them explicitely.  */
 522       {
 523         gphi *phi = as_a <gphi *> (stmt);
 524         if (wi)
 525           {
 526             wi->val_only = true;
 527             wi->is_lhs = true;
 528           }
 529         ret = walk_tree (gimple_phi_result_ptr (phi), callback_op, wi, pset);
 530         if (wi)
 531           wi->is_lhs = false;
 532         if (ret)
 533           return ret;
 534         for (unsigned i = 0; i < gimple_phi_num_args (phi); ++i)
 535           {
 536             ret = walk_tree (gimple_phi_arg_def_ptr (phi, i),
 537                              callback_op, wi, pset);
 538             if (ret)
 539               return ret;
 540           }
 541         break;
 542       }
 543
 544     default:
 545       {
 546         enum gimple_statement_structure_enum gss;
 547         gss = gimple_statement_structure (stmt);
 548         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 549           for (i = 0; i < gimple_num_ops (stmt); i++)
 550             {
 551               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 552               if (ret)
 553                 return ret;
 554             }
 555       }
 556       break;
 557     }
 558
 559   return NULL_TREE;
 560 }
 561
 562
 563 /* Walk the current statement in GSI (optionally using traversal state
 564    stored in WI).  If WI is NULL, no state is kept during traversal.
 565    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 566    that it has handled all the operands of the statement, its return
 567    value is returned.  Otherwise, the return value from CALLBACK_STMT
 568    is discarded and its operands are scanned.
 569
 570    If CALLBACK_STMT is NULL or it didn't handle the operands,
 571    CALLBACK_OP is called on each operand of the statement via
 572    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 573    operand, the remaining operands are not scanned.  In this case, the
 574    return value from CALLBACK_OP is returned.
 575
 576    In any other case, NULL_TREE is returned.  */
 577
 578 tree
 579 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 580                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 581 {
 582   gimple *ret;
 583   tree tree_ret;
 584   gimple *stmt = gsi_stmt (*gsi);
 585
 586   if (wi)
 587     {
 588       wi->gsi = *gsi;
 589       wi->removed_stmt = false;
 590
 591       if (wi->want_locations && gimple_has_location (stmt))
 592         input_location = gimple_location (stmt);
 593     }
 594
 595   ret = NULL;
 596
 597   /* Invoke the statement callback.  Return if the callback handled
 598      all of STMT operands by itself.  */
 599   if (callback_stmt)
 600     {
 601       bool handled_ops = false;
 602       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 603       if (handled_ops)
 604         return tree_ret;
 605
 606       /* If CALLBACK_STMT did not handle operands, it should not have
 607          a value to return.  */
 608       gcc_assert (tree_ret == NULL);
 609
 610       if (wi && wi->removed_stmt)
 611         return NULL;
 612
 613       /* Re-read stmt in case the callback changed it.  */
 614       stmt = gsi_stmt (*gsi);
 615     }
 616
 617   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 618   if (callback_op)
 619     {
 620       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 621       if (tree_ret)
 622         return tree_ret;
 623     }
 624
 625   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 626   switch (gimple_code (stmt))
 627     {
 628     case GIMPLE_BIND:
 629       ret = walk_gimple_seq_mod (gimple_bind_body_ptr (as_a <gbind *> (stmt)),
 630                                  callback_stmt, callback_op, wi);
 631       if (ret)
 632         return wi->callback_result;
 633       break;
 634
 635     case GIMPLE_CATCH:
 636       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (
 637                                    as_a <gcatch *> (stmt)),
 638                                  callback_stmt, callback_op, wi);
 639       if (ret)
 640         return wi->callback_result;
 641       break;
 642
 643     case GIMPLE_EH_FILTER:
 644       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 645                              callback_op, wi);
 646       if (ret)
 647         return wi->callback_result;
 648       break;
 649
 650     case GIMPLE_EH_ELSE:
 651       {
 652         geh_else *eh_else_stmt = as_a <geh_else *> (stmt);
 653         ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (eh_else_stmt),
 654                                    callback_stmt, callback_op, wi);
 655         if (ret)
 656           return wi->callback_result;
 657         ret = walk_gimple_seq_mod (gimple_eh_else_e_body_ptr (eh_else_stmt),
 658                                    callback_stmt, callback_op, wi);
 659         if (ret)
 660           return wi->callback_result;
 661       }
 662       break;
 663
 664     case GIMPLE_TRY:
 665       ret = walk_gimple_seq_mod (gimple_try_eval_ptr (stmt), callback_stmt, callback_op,
 666                              wi);
 667       if (ret)
 668         return wi->callback_result;
 669
 670       ret = walk_gimple_seq_mod (gimple_try_cleanup_ptr (stmt), callback_stmt,
 671                              callback_op, wi);
 672       if (ret)
 673         return wi->callback_result;
 674       break;
 675
 676     case GIMPLE_OMP_FOR:
 677       ret = walk_gimple_seq_mod (gimple_omp_for_pre_body_ptr (stmt), callback_stmt,
 678                              callback_op, wi);
 679       if (ret)
 680         return wi->callback_result;
 681
 682       /* FALL THROUGH.  */
 683     case GIMPLE_OMP_CRITICAL:
 684     case GIMPLE_OMP_MASTER:
 685     case GIMPLE_OMP_MASKED:
 686     case GIMPLE_OMP_TASKGROUP:
 687     case GIMPLE_OMP_ORDERED:
 688     case GIMPLE_OMP_SCAN:
 689     case GIMPLE_OMP_SECTION:
 690     case GIMPLE_OMP_PARALLEL:
 691     case GIMPLE_OMP_TASK:
 692     case GIMPLE_OMP_SCOPE:
 693     case GIMPLE_OMP_SECTIONS:
 694     case GIMPLE_OMP_SINGLE:
 695     case GIMPLE_OMP_TARGET:
 696     case GIMPLE_OMP_TEAMS:
 697       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 698                              callback_op, wi);
 699       if (ret)
 700         return wi->callback_result;
 701       break;
 702
 703     case GIMPLE_WITH_CLEANUP_EXPR:
 704       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 705                              callback_op, wi);
 706       if (ret)
 707         return wi->callback_result;
 708       break;
 709
 710     case GIMPLE_TRANSACTION:
 711       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (
 712                                    as_a <gtransaction *> (stmt)),
 713                              callback_stmt, callback_op, wi);
 714       if (ret)
 715         return wi->callback_result;
 716       break;
 717
 718     default:
 719       gcc_assert (!gimple_has_substatements (stmt));
 720       break;
 721     }
 722
 723   return NULL;
 724 }
 725
 726 /* From a tree operand OP return the base of a load or store operation
 727    or NULL_TREE if OP is not a load or a store.  */
 728
 729 static tree
 730 get_base_loadstore (tree op)
 731 {
 732   while (handled_component_p (op))
 733     op = TREE_OPERAND (op, 0);
 734   if (DECL_P (op)
 735       || INDIRECT_REF_P (op)
 736       || TREE_CODE (op) == MEM_REF
 737       || TREE_CODE (op) == TARGET_MEM_REF)
 738     return op;
 739   return NULL_TREE;
 740 }
 741
 742
 743 /* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
 744    VISIT_ADDR if non-NULL on loads, store and address-taken operands
 745    passing the STMT, the base of the operand, the operand itself containing
 746    the base and DATA to it.  The base will be either a decl, an indirect
 747    reference (including TARGET_MEM_REF) or the argument of an address
 748    expression.
 749    Returns the results of these callbacks or'ed.  */
 750
 751 bool
 752 walk_stmt_load_store_addr_ops (gimple *stmt, void *data,
 753                                walk_stmt_load_store_addr_fn visit_load,
 754                                walk_stmt_load_store_addr_fn visit_store,
 755                                walk_stmt_load_store_addr_fn visit_addr)
 756 {
 757   bool ret = false;
 758   unsigned i;
 759   if (gimple_assign_single_p (stmt))
 760     {
 761       tree lhs, rhs, arg;
 762       if (visit_store)
 763         {
 764           arg = gimple_assign_lhs (stmt);
 765           lhs = get_base_loadstore (arg);
 766           if (lhs)
 767             ret |= visit_store (stmt, lhs, arg, data);
 768         }
 769       arg = gimple_assign_rhs1 (stmt);
 770       rhs = arg;
 771       while (handled_component_p (rhs))
 772         rhs = TREE_OPERAND (rhs, 0);
 773       if (visit_addr)
 774         {
 775           if (TREE_CODE (rhs) == ADDR_EXPR)
 776             ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), arg, data);
 777           else if (TREE_CODE (rhs) == OBJ_TYPE_REF
 778                    && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
 779             ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
 780                                                    0), arg, data);
 781           else if (TREE_CODE (rhs) == CONSTRUCTOR)
 782             {
 783               unsigned int ix;
 784               tree val;
 785
 786               FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), ix, val)
 787                 if (TREE_CODE (val) == ADDR_EXPR)
 788                   ret |= visit_addr (stmt, TREE_OPERAND (val, 0), arg, data);
 789                 else if (TREE_CODE (val) == OBJ_TYPE_REF
 790                          && TREE_CODE (OBJ_TYPE_REF_OBJECT (val)) == ADDR_EXPR)
 791                   ret |= visit_addr (stmt,
 792                                      TREE_OPERAND (OBJ_TYPE_REF_OBJECT (val),
 793                                                    0), arg, data);
 794             }
 795         }
 796       if (visit_load)
 797         {
 798           rhs = get_base_loadstore (rhs);
 799           if (rhs)
 800             ret |= visit_load (stmt, rhs, arg, data);
 801         }
 802     }
 803   else if (visit_addr
 804            && (is_gimple_assign (stmt)
 805                || gimple_code (stmt) == GIMPLE_COND))
 806     {
 807       for (i = 0; i < gimple_num_ops (stmt); ++i)
 808         {
 809           tree op = gimple_op (stmt, i);
 810           if (op == NULL_TREE)
 811             ;
 812           else if (TREE_CODE (op) == ADDR_EXPR)
 813             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 814           /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
 815              tree with two operands.  */
 816           else if (i == 1 && COMPARISON_CLASS_P (op))
 817             {
 818               if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
 819                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
 820                                                        0), op, data);
 821               if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
 822                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
 823                                                        0), op, data);
 824             }
 825         }
 826     }
 827   else if (gcall *call_stmt = dyn_cast <gcall *> (stmt))
 828     {
 829       if (visit_store)
 830         {
 831           tree arg = gimple_call_lhs (call_stmt);
 832           if (arg)
 833             {
 834               tree lhs = get_base_loadstore (arg);
 835               if (lhs)
 836                 ret |= visit_store (stmt, lhs, arg, data);
 837             }
 838         }
 839       if (visit_load || visit_addr)
 840         for (i = 0; i < gimple_call_num_args (call_stmt); ++i)
 841           {
 842             tree arg = gimple_call_arg (call_stmt, i);
 843             if (visit_addr
 844                 && TREE_CODE (arg) == ADDR_EXPR)
 845               ret |= visit_addr (stmt, TREE_OPERAND (arg, 0), arg, data);
 846             else if (visit_load)
 847               {
 848                 tree rhs = get_base_loadstore (arg);
 849                 if (rhs)
 850                   ret |= visit_load (stmt, rhs, arg, data);
 851               }
 852           }
 853       if (visit_addr
 854           && gimple_call_chain (call_stmt)
 855           && TREE_CODE (gimple_call_chain (call_stmt)) == ADDR_EXPR)
 856         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (call_stmt), 0),
 857                            gimple_call_chain (call_stmt), data);
 858       if (visit_addr
 859           && gimple_call_return_slot_opt_p (call_stmt)
 860           && gimple_call_lhs (call_stmt) != NULL_TREE
 861           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (call_stmt))))
 862         ret |= visit_addr (stmt, gimple_call_lhs (call_stmt),
 863                            gimple_call_lhs (call_stmt), data);
 864     }
 865   else if (gasm *asm_stmt = dyn_cast <gasm *> (stmt))
 866     {
 867       unsigned noutputs;
 868       const char *constraint;
 869       const char **oconstraints;
 870       bool allows_mem, allows_reg, is_inout;
 871       noutputs = gimple_asm_noutputs (asm_stmt);
 872       oconstraints = XALLOCAVEC (const char *, noutputs);
 873       if (visit_store || visit_addr)
 874         for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
 875           {
 876             tree link = gimple_asm_output_op (asm_stmt, i);
 877             tree op = get_base_loadstore (TREE_VALUE (link));
 878             if (op && visit_store)
 879               ret |= visit_store (stmt, op, TREE_VALUE (link), data);
 880             if (visit_addr)
 881               {
 882                 constraint = TREE_STRING_POINTER
 883                     (TREE_VALUE (TREE_PURPOSE (link)));
 884                 oconstraints[i] = constraint;
 885                 parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 886                                          &allows_reg, &is_inout);
 887                 if (op && !allows_reg && allows_mem)
 888                   ret |= visit_addr (stmt, op, TREE_VALUE (link), data);
 889               }
 890           }
 891       if (visit_load || visit_addr)
 892         for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
 893           {
 894             tree link = gimple_asm_input_op (asm_stmt, i);
 895             tree op = TREE_VALUE (link);
 896             if (visit_addr
 897                 && TREE_CODE (op) == ADDR_EXPR)
 898               ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 899             else if (visit_load || visit_addr)
 900               {
 901                 op = get_base_loadstore (op);
 902                 if (op)
 903                   {
 904                     if (visit_load)
 905                       ret |= visit_load (stmt, op, TREE_VALUE (link), data);
 906                     if (visit_addr)
 907                       {
 908                         constraint = TREE_STRING_POINTER
 909                             (TREE_VALUE (TREE_PURPOSE (link)));
 910                         parse_input_constraint (&constraint, 0, 0, noutputs,
 911                                                 0, oconstraints,
 912                                                 &allows_mem, &allows_reg);
 913                         if (!allows_reg && allows_mem)
 914                           ret |= visit_addr (stmt, op, TREE_VALUE (link),
 915                                              data);
 916                       }
 917                   }
 918               }
 919           }
 920     }
 921   else if (greturn *return_stmt = dyn_cast <greturn *> (stmt))
 922     {
 923       tree op = gimple_return_retval (return_stmt);
 924       if (op)
 925         {
 926           if (visit_addr
 927               && TREE_CODE (op) == ADDR_EXPR)
 928             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 929           else if (visit_load)
 930             {
 931               tree base = get_base_loadstore (op);
 932               if (base)
 933                 ret |= visit_load (stmt, base, op, data);
 934             }
 935         }
 936     }
 937   else if (visit_addr
 938            && gimple_code (stmt) == GIMPLE_PHI)
 939     {
 940       for (i = 0; i < gimple_phi_num_args (stmt); ++i)
 941         {
 942           tree op = gimple_phi_arg_def (stmt, i);
 943           if (TREE_CODE (op) == ADDR_EXPR)
 944             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 945         }
 946     }
 947   else if (visit_addr
 948            && gimple_code (stmt) == GIMPLE_GOTO)
 949     {
 950       tree op = gimple_goto_dest (stmt);
 951       if (TREE_CODE (op) == ADDR_EXPR)
 952         ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 953     }
 954
 955   return ret;
 956 }
 957
 958 /* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
 959    should make a faster clone for this case.  */
 960
 961 bool
 962 walk_stmt_load_store_ops (gimple *stmt, void *data,
 963                           walk_stmt_load_store_addr_fn visit_load,
 964                           walk_stmt_load_store_addr_fn visit_store)
 965 {
 966   return walk_stmt_load_store_addr_ops (stmt, data,
 967                                         visit_load, visit_store, NULL);
 968 }