gcc/gimple-walk.cc

   1 /* Gimple walk support.
   2
   3    Copyright (C) 2007-2023 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_ASSUME:
 489       ret = walk_tree (gimple_assume_guard_ptr (stmt), callback_op, wi, pset);
 490       if (ret)
 491         return ret;
 492       break;
 493
 494     case GIMPLE_TRANSACTION:
 495       {
 496         gtransaction *txn = as_a <gtransaction *> (stmt);
 497
 498         ret = walk_tree (gimple_transaction_label_norm_ptr (txn),
 499                          callback_op, wi, pset);
 500         if (ret)
 501           return ret;
 502         ret = walk_tree (gimple_transaction_label_uninst_ptr (txn),
 503                          callback_op, wi, pset);
 504         if (ret)
 505           return ret;
 506         ret = walk_tree (gimple_transaction_label_over_ptr (txn),
 507                          callback_op, wi, pset);
 508         if (ret)
 509           return ret;
 510       }
 511       break;
 512
 513     case GIMPLE_OMP_RETURN:
 514       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 515                        pset);
 516       if (ret)
 517         return ret;
 518       break;
 519
 520       /* Tuples that do not have operands.  */
 521     case GIMPLE_NOP:
 522     case GIMPLE_RESX:
 523     case GIMPLE_PREDICT:
 524       break;
 525
 526     case GIMPLE_PHI:
 527       /* PHIs are not GSS_WITH_OPS so we need to handle them explicitely.  */
 528       {
 529         gphi *phi = as_a <gphi *> (stmt);
 530         if (wi)
 531           {
 532             wi->val_only = true;
 533             wi->is_lhs = true;
 534           }
 535         ret = walk_tree (gimple_phi_result_ptr (phi), callback_op, wi, pset);
 536         if (wi)
 537           wi->is_lhs = false;
 538         if (ret)
 539           return ret;
 540         for (unsigned i = 0; i < gimple_phi_num_args (phi); ++i)
 541           {
 542             ret = walk_tree (gimple_phi_arg_def_ptr (phi, i),
 543                              callback_op, wi, pset);
 544             if (ret)
 545               return ret;
 546           }
 547         break;
 548       }
 549
 550     default:
 551       {
 552         enum gimple_statement_structure_enum gss;
 553         gss = gimple_statement_structure (stmt);
 554         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 555           for (i = 0; i < gimple_num_ops (stmt); i++)
 556             {
 557               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 558               if (ret)
 559                 return ret;
 560             }
 561       }
 562       break;
 563     }
 564
 565   return NULL_TREE;
 566 }
 567
 568
 569 /* Walk the current statement in GSI (optionally using traversal state
 570    stored in WI).  If WI is NULL, no state is kept during traversal.
 571    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 572    that it has handled all the operands of the statement, its return
 573    value is returned.  Otherwise, the return value from CALLBACK_STMT
 574    is discarded and its operands are scanned.
 575
 576    If CALLBACK_STMT is NULL or it didn't handle the operands,
 577    CALLBACK_OP is called on each operand of the statement via
 578    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 579    operand, the remaining operands are not scanned.  In this case, the
 580    return value from CALLBACK_OP is returned.
 581
 582    In any other case, NULL_TREE is returned.  */
 583
 584 tree
 585 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 586                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 587 {
 588   gimple *ret;
 589   tree tree_ret;
 590   gimple *stmt = gsi_stmt (*gsi);
 591
 592   if (wi)
 593     {
 594       wi->gsi = *gsi;
 595       wi->removed_stmt = false;
 596
 597       if (wi->want_locations && gimple_has_location (stmt))
 598         input_location = gimple_location (stmt);
 599     }
 600
 601   ret = NULL;
 602
 603   /* Invoke the statement callback.  Return if the callback handled
 604      all of STMT operands by itself.  */
 605   if (callback_stmt)
 606     {
 607       bool handled_ops = false;
 608       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 609       if (handled_ops)
 610         return tree_ret;
 611
 612       /* If CALLBACK_STMT did not handle operands, it should not have
 613          a value to return.  */
 614       gcc_assert (tree_ret == NULL);
 615
 616       if (wi && wi->removed_stmt)
 617         return NULL;
 618
 619       /* Re-read stmt in case the callback changed it.  */
 620       stmt = gsi_stmt (*gsi);
 621     }
 622
 623   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 624   if (callback_op)
 625     {
 626       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 627       if (tree_ret)
 628         return tree_ret;
 629     }
 630
 631   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 632   switch (gimple_code (stmt))
 633     {
 634     case GIMPLE_BIND:
 635       ret = walk_gimple_seq_mod (gimple_bind_body_ptr (as_a <gbind *> (stmt)),
 636                                  callback_stmt, callback_op, wi);
 637       if (ret)
 638         return wi->callback_result;
 639       break;
 640
 641     case GIMPLE_CATCH:
 642       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (
 643                                    as_a <gcatch *> (stmt)),
 644                                  callback_stmt, callback_op, wi);
 645       if (ret)
 646         return wi->callback_result;
 647       break;
 648
 649     case GIMPLE_EH_FILTER:
 650       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 651                              callback_op, wi);
 652       if (ret)
 653         return wi->callback_result;
 654       break;
 655
 656     case GIMPLE_EH_ELSE:
 657       {
 658         geh_else *eh_else_stmt = as_a <geh_else *> (stmt);
 659         ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (eh_else_stmt),
 660                                    callback_stmt, callback_op, wi);
 661         if (ret)
 662           return wi->callback_result;
 663         ret = walk_gimple_seq_mod (gimple_eh_else_e_body_ptr (eh_else_stmt),
 664                                    callback_stmt, callback_op, wi);
 665         if (ret)
 666           return wi->callback_result;
 667       }
 668       break;
 669
 670     case GIMPLE_TRY:
 671       ret = walk_gimple_seq_mod (gimple_try_eval_ptr (stmt), callback_stmt, callback_op,
 672                              wi);
 673       if (ret)
 674         return wi->callback_result;
 675
 676       ret = walk_gimple_seq_mod (gimple_try_cleanup_ptr (stmt), callback_stmt,
 677                              callback_op, wi);
 678       if (ret)
 679         return wi->callback_result;
 680       break;
 681
 682     case GIMPLE_OMP_FOR:
 683       ret = walk_gimple_seq_mod (gimple_omp_for_pre_body_ptr (stmt), callback_stmt,
 684                              callback_op, wi);
 685       if (ret)
 686         return wi->callback_result;
 687
 688       /* FALL THROUGH.  */
 689     case GIMPLE_OMP_CRITICAL:
 690     case GIMPLE_OMP_MASTER:
 691     case GIMPLE_OMP_MASKED:
 692     case GIMPLE_OMP_TASKGROUP:
 693     case GIMPLE_OMP_ORDERED:
 694     case GIMPLE_OMP_SCAN:
 695     case GIMPLE_OMP_SECTION:
 696     case GIMPLE_OMP_STRUCTURED_BLOCK:
 697     case GIMPLE_OMP_PARALLEL:
 698     case GIMPLE_OMP_TASK:
 699     case GIMPLE_OMP_SCOPE:
 700     case GIMPLE_OMP_SECTIONS:
 701     case GIMPLE_OMP_SINGLE:
 702     case GIMPLE_OMP_TARGET:
 703     case GIMPLE_OMP_TEAMS:
 704       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 705                              callback_op, wi);
 706       if (ret)
 707         return wi->callback_result;
 708       break;
 709
 710     case GIMPLE_WITH_CLEANUP_EXPR:
 711       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 712                              callback_op, wi);
 713       if (ret)
 714         return wi->callback_result;
 715       break;
 716
 717     case GIMPLE_ASSUME:
 718       ret = walk_gimple_seq_mod (gimple_assume_body_ptr (stmt),
 719                                  callback_stmt, callback_op, wi);
 720       if (ret)
 721         return wi->callback_result;
 722       break;
 723
 724     case GIMPLE_TRANSACTION:
 725       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (
 726                                    as_a <gtransaction *> (stmt)),
 727                              callback_stmt, callback_op, wi);
 728       if (ret)
 729         return wi->callback_result;
 730       break;
 731
 732     default:
 733       gcc_assert (!gimple_has_substatements (stmt));
 734       break;
 735     }
 736
 737   return NULL;
 738 }
 739
 740 /* From a tree operand OP return the base of a load or store operation
 741    or NULL_TREE if OP is not a load or a store.  */
 742
 743 static tree
 744 get_base_loadstore (tree op)
 745 {
 746   while (handled_component_p (op))
 747     op = TREE_OPERAND (op, 0);
 748   if (DECL_P (op)
 749       || INDIRECT_REF_P (op)
 750       || TREE_CODE (op) == MEM_REF
 751       || TREE_CODE (op) == TARGET_MEM_REF)
 752     return op;
 753   return NULL_TREE;
 754 }
 755
 756
 757 /* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
 758    VISIT_ADDR if non-NULL on loads, store and address-taken operands
 759    passing the STMT, the base of the operand, the operand itself containing
 760    the base and DATA to it.  The base will be either a decl, an indirect
 761    reference (including TARGET_MEM_REF) or the argument of an address
 762    expression.
 763    Returns the results of these callbacks or'ed.  */
 764
 765 bool
 766 walk_stmt_load_store_addr_ops (gimple *stmt, void *data,
 767                                walk_stmt_load_store_addr_fn visit_load,
 768                                walk_stmt_load_store_addr_fn visit_store,
 769                                walk_stmt_load_store_addr_fn visit_addr)
 770 {
 771   bool ret = false;
 772   unsigned i;
 773   if (gimple_assign_single_p (stmt))
 774     {
 775       tree lhs, rhs, arg;
 776       if (visit_store)
 777         {
 778           arg = gimple_assign_lhs (stmt);
 779           lhs = get_base_loadstore (arg);
 780           if (lhs)
 781             ret |= visit_store (stmt, lhs, arg, data);
 782         }
 783       arg = gimple_assign_rhs1 (stmt);
 784       rhs = arg;
 785       while (handled_component_p (rhs))
 786         rhs = TREE_OPERAND (rhs, 0);
 787       if (visit_addr)
 788         {
 789           if (TREE_CODE (rhs) == ADDR_EXPR)
 790             ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), arg, data);
 791           else if (TREE_CODE (rhs) == OBJ_TYPE_REF
 792                    && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
 793             ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
 794                                                    0), arg, data);
 795           else if (TREE_CODE (rhs) == CONSTRUCTOR)
 796             {
 797               unsigned int ix;
 798               tree val;
 799
 800               FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), ix, val)
 801                 if (TREE_CODE (val) == ADDR_EXPR)
 802                   ret |= visit_addr (stmt, TREE_OPERAND (val, 0), arg, data);
 803                 else if (TREE_CODE (val) == OBJ_TYPE_REF
 804                          && TREE_CODE (OBJ_TYPE_REF_OBJECT (val)) == ADDR_EXPR)
 805                   ret |= visit_addr (stmt,
 806                                      TREE_OPERAND (OBJ_TYPE_REF_OBJECT (val),
 807                                                    0), arg, data);
 808             }
 809         }
 810       if (visit_load)
 811         {
 812           rhs = get_base_loadstore (rhs);
 813           if (rhs)
 814             ret |= visit_load (stmt, rhs, arg, data);
 815         }
 816     }
 817   else if (visit_addr
 818            && (is_gimple_assign (stmt)
 819                || gimple_code (stmt) == GIMPLE_COND))
 820     {
 821       for (i = 0; i < gimple_num_ops (stmt); ++i)
 822         {
 823           tree op = gimple_op (stmt, i);
 824           if (op == NULL_TREE)
 825             ;
 826           else if (TREE_CODE (op) == ADDR_EXPR)
 827             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 828           /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
 829              tree with two operands.  */
 830           else if (i == 1 && COMPARISON_CLASS_P (op))
 831             {
 832               if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
 833                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
 834                                                        0), op, data);
 835               if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
 836                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
 837                                                        0), op, data);
 838             }
 839         }
 840     }
 841   else if (gcall *call_stmt = dyn_cast <gcall *> (stmt))
 842     {
 843       if (visit_store)
 844         {
 845           tree arg = gimple_call_lhs (call_stmt);
 846           if (arg)
 847             {
 848               tree lhs = get_base_loadstore (arg);
 849               if (lhs)
 850                 ret |= visit_store (stmt, lhs, arg, data);
 851             }
 852         }
 853       if (visit_load || visit_addr)
 854         for (i = 0; i < gimple_call_num_args (call_stmt); ++i)
 855           {
 856             tree arg = gimple_call_arg (call_stmt, i);
 857             if (visit_addr
 858                 && TREE_CODE (arg) == ADDR_EXPR)
 859               ret |= visit_addr (stmt, TREE_OPERAND (arg, 0), arg, data);
 860             else if (visit_load)
 861               {
 862                 tree rhs = get_base_loadstore (arg);
 863                 if (rhs)
 864                   ret |= visit_load (stmt, rhs, arg, data);
 865               }
 866           }
 867       if (visit_addr
 868           && gimple_call_chain (call_stmt)
 869           && TREE_CODE (gimple_call_chain (call_stmt)) == ADDR_EXPR)
 870         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (call_stmt), 0),
 871                            gimple_call_chain (call_stmt), data);
 872       if (visit_addr
 873           && gimple_call_return_slot_opt_p (call_stmt)
 874           && gimple_call_lhs (call_stmt) != NULL_TREE
 875           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (call_stmt))))
 876         ret |= visit_addr (stmt, gimple_call_lhs (call_stmt),
 877                            gimple_call_lhs (call_stmt), data);
 878     }
 879   else if (gasm *asm_stmt = dyn_cast <gasm *> (stmt))
 880     {
 881       unsigned noutputs;
 882       const char *constraint;
 883       const char **oconstraints;
 884       bool allows_mem, allows_reg, is_inout;
 885       noutputs = gimple_asm_noutputs (asm_stmt);
 886       oconstraints = XALLOCAVEC (const char *, noutputs);
 887       if (visit_store || visit_addr)
 888         for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
 889           {
 890             tree link = gimple_asm_output_op (asm_stmt, i);
 891             tree op = get_base_loadstore (TREE_VALUE (link));
 892             if (op && visit_store)
 893               ret |= visit_store (stmt, op, TREE_VALUE (link), data);
 894             if (visit_addr)
 895               {
 896                 constraint = TREE_STRING_POINTER
 897                     (TREE_VALUE (TREE_PURPOSE (link)));
 898                 oconstraints[i] = constraint;
 899                 parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 900                                          &allows_reg, &is_inout);
 901                 if (op && !allows_reg && allows_mem)
 902                   ret |= visit_addr (stmt, op, TREE_VALUE (link), data);
 903               }
 904           }
 905       if (visit_load || visit_addr)
 906         for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
 907           {
 908             tree link = gimple_asm_input_op (asm_stmt, i);
 909             tree op = TREE_VALUE (link);
 910             if (visit_addr
 911                 && TREE_CODE (op) == ADDR_EXPR)
 912               ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 913             else if (visit_load || visit_addr)
 914               {
 915                 op = get_base_loadstore (op);
 916                 if (op)
 917                   {
 918                     if (visit_load)
 919                       ret |= visit_load (stmt, op, TREE_VALUE (link), data);
 920                     if (visit_addr)
 921                       {
 922                         constraint = TREE_STRING_POINTER
 923                             (TREE_VALUE (TREE_PURPOSE (link)));
 924                         parse_input_constraint (&constraint, 0, 0, noutputs,
 925                                                 0, oconstraints,
 926                                                 &allows_mem, &allows_reg);
 927                         if (!allows_reg && allows_mem)
 928                           ret |= visit_addr (stmt, op, TREE_VALUE (link),
 929                                              data);
 930                       }
 931                   }
 932               }
 933           }
 934     }
 935   else if (greturn *return_stmt = dyn_cast <greturn *> (stmt))
 936     {
 937       tree op = gimple_return_retval (return_stmt);
 938       if (op)
 939         {
 940           if (visit_addr
 941               && TREE_CODE (op) == ADDR_EXPR)
 942             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 943           else if (visit_load)
 944             {
 945               tree base = get_base_loadstore (op);
 946               if (base)
 947                 ret |= visit_load (stmt, base, op, data);
 948             }
 949         }
 950     }
 951   else if (visit_addr
 952            && gimple_code (stmt) == GIMPLE_PHI)
 953     {
 954       for (i = 0; i < gimple_phi_num_args (stmt); ++i)
 955         {
 956           tree op = gimple_phi_arg_def (stmt, i);
 957           if (TREE_CODE (op) == ADDR_EXPR)
 958             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 959         }
 960     }
 961   else if (visit_addr
 962            && gimple_code (stmt) == GIMPLE_GOTO)
 963     {
 964       tree op = gimple_goto_dest (stmt);
 965       if (TREE_CODE (op) == ADDR_EXPR)
 966         ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 967     }
 968
 969   return ret;
 970 }
 971
 972 /* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
 973    should make a faster clone for this case.  */
 974
 975 bool
 976 walk_stmt_load_store_ops (gimple *stmt, void *data,
 977                           walk_stmt_load_store_addr_fn visit_load,
 978                           walk_stmt_load_store_addr_fn visit_store)
 979 {
 980   return walk_stmt_load_store_addr_ops (stmt, data,
 981                                         visit_load, visit_store, NULL);
 982 }