gcc/gimple-walk.c

   1 /* Gimple walk support.
   2
   3    Copyright (C) 2007-2014 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 "tm.h"
  26 #include "tree.h"
  27 #include "stmt.h"
  28 #include "basic-block.h"
  29 #include "tree-ssa-alias.h"
  30 #include "internal-fn.h"
  31 #include "gimple-expr.h"
  32 #include "is-a.h"
  33 #include "gimple.h"
  34 #include "gimple-iterator.h"
  35 #include "gimple-walk.h"
  36 #include "gimple-walk.h"
  37 #include "demangle.h"
  38
  39 /* Walk all the statements in the sequence *PSEQ calling walk_gimple_stmt
  40    on each one.  WI is as in walk_gimple_stmt.
  41
  42    If walk_gimple_stmt returns non-NULL, the walk is stopped, and the
  43    value is stored in WI->CALLBACK_RESULT.  Also, the statement that
  44    produced the value is returned if this statement has not been
  45    removed by a callback (wi->removed_stmt).  If the statement has
  46    been removed, NULL is returned.
  47
  48    Otherwise, all the statements are walked and NULL returned.  */
  49
  50 gimple
  51 walk_gimple_seq_mod (gimple_seq *pseq, walk_stmt_fn callback_stmt,
  52                      walk_tree_fn callback_op, struct walk_stmt_info *wi)
  53 {
  54   gimple_stmt_iterator gsi;
  55
  56   for (gsi = gsi_start (*pseq); !gsi_end_p (gsi); )
  57     {
  58       tree ret = walk_gimple_stmt (&gsi, callback_stmt, callback_op, wi);
  59       if (ret)
  60         {
  61           /* If CALLBACK_STMT or CALLBACK_OP return a value, WI must exist
  62              to hold it.  */
  63           gcc_assert (wi);
  64           wi->callback_result = ret;
  65
  66           return wi->removed_stmt ? NULL : gsi_stmt (gsi);
  67         }
  68
  69       if (!wi->removed_stmt)
  70         gsi_next (&gsi);
  71     }
  72
  73   if (wi)
  74     wi->callback_result = NULL_TREE;
  75
  76   return NULL;
  77 }
  78
  79
  80 /* Like walk_gimple_seq_mod, but ensure that the head of SEQ isn't
  81    changed by the callbacks.  */
  82
  83 gimple
  84 walk_gimple_seq (gimple_seq seq, walk_stmt_fn callback_stmt,
  85                  walk_tree_fn callback_op, struct walk_stmt_info *wi)
  86 {
  87   gimple_seq seq2 = seq;
  88   gimple ret = walk_gimple_seq_mod (&seq2, callback_stmt, callback_op, wi);
  89   gcc_assert (seq2 == seq);
  90   return ret;
  91 }
  92
  93
  94 /* Helper function for walk_gimple_stmt.  Walk operands of a GIMPLE_ASM.  */
  95
  96 static tree
  97 walk_gimple_asm (gimple_asm stmt, walk_tree_fn callback_op,
  98                  struct walk_stmt_info *wi)
  99 {
 100   tree ret, op;
 101   unsigned noutputs;
 102   const char **oconstraints;
 103   unsigned i, n;
 104   const char *constraint;
 105   bool allows_mem, allows_reg, is_inout;
 106
 107   noutputs = gimple_asm_noutputs (stmt);
 108   oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *));
 109
 110   if (wi)
 111     wi->is_lhs = true;
 112
 113   for (i = 0; i < noutputs; i++)
 114     {
 115       op = gimple_asm_output_op (stmt, i);
 116       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 117       oconstraints[i] = constraint;
 118       parse_output_constraint (&constraint, i, 0, 0, &allows_mem, &allows_reg,
 119                                &is_inout);
 120       if (wi)
 121         wi->val_only = (allows_reg || !allows_mem);
 122       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 123       if (ret)
 124         return ret;
 125     }
 126
 127   n = gimple_asm_ninputs (stmt);
 128   for (i = 0; i < n; i++)
 129     {
 130       op = gimple_asm_input_op (stmt, i);
 131       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 132       parse_input_constraint (&constraint, 0, 0, noutputs, 0,
 133                               oconstraints, &allows_mem, &allows_reg);
 134       if (wi)
 135         {
 136           wi->val_only = (allows_reg || !allows_mem);
 137           /* Although input "m" is not really a LHS, we need a lvalue.  */
 138           wi->is_lhs = !wi->val_only;
 139         }
 140       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 141       if (ret)
 142         return ret;
 143     }
 144
 145   if (wi)
 146     {
 147       wi->is_lhs = false;
 148       wi->val_only = true;
 149     }
 150
 151   n = gimple_asm_nlabels (stmt);
 152   for (i = 0; i < n; i++)
 153     {
 154       op = gimple_asm_label_op (stmt, i);
 155       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 156       if (ret)
 157         return ret;
 158     }
 159
 160   return NULL_TREE;
 161 }
 162
 163
 164 /* Helper function of WALK_GIMPLE_STMT.  Walk every tree operand in
 165    STMT.  CALLBACK_OP and WI are as in WALK_GIMPLE_STMT.
 166
 167    CALLBACK_OP is called on each operand of STMT via walk_tree.
 168    Additional parameters to walk_tree must be stored in WI.  For each operand
 169    OP, walk_tree is called as:
 170
 171         walk_tree (&OP, CALLBACK_OP, WI, WI->PSET)
 172
 173    If CALLBACK_OP returns non-NULL for an operand, the remaining
 174    operands are not scanned.
 175
 176    The return value is that returned by the last call to walk_tree, or
 177    NULL_TREE if no CALLBACK_OP is specified.  */
 178
 179 tree
 180 walk_gimple_op (gimple stmt, walk_tree_fn callback_op,
 181                 struct walk_stmt_info *wi)
 182 {
 183   hash_set<tree> *pset = (wi) ? wi->pset : NULL;
 184   unsigned i;
 185   tree ret = NULL_TREE;
 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 <gimple_call> (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 <gimple_catch> (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 <gimple_asm> (stmt), callback_op, wi);
 296       if (ret)
 297         return ret;
 298       break;
 299
 300     case GIMPLE_OMP_CONTINUE:
 301       {
 302         gimple_omp_continue cont_stmt = as_a <gimple_omp_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       ret = walk_tree (gimple_omp_critical_name_ptr (stmt), callback_op, wi,
 317                        pset);
 318       if (ret)
 319         return ret;
 320       break;
 321
 322     case GIMPLE_OMP_FOR:
 323       ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
 324                        pset);
 325       if (ret)
 326         return ret;
 327       for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
 328         {
 329           ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
 330                            wi, pset);
 331           if (ret)
 332             return ret;
 333           ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
 334                            wi, pset);
 335           if (ret)
 336             return ret;
 337           ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
 338                            wi, pset);
 339           if (ret)
 340             return ret;
 341           ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
 342                            wi, pset);
 343         }
 344       if (ret)
 345         return ret;
 346       break;
 347
 348     case GIMPLE_OMP_PARALLEL:
 349       ret = walk_tree (gimple_omp_parallel_clauses_ptr (stmt), callback_op,
 350                        wi, pset);
 351       if (ret)
 352         return ret;
 353       ret = walk_tree (gimple_omp_parallel_child_fn_ptr (stmt), callback_op,
 354                        wi, pset);
 355       if (ret)
 356         return ret;
 357       ret = walk_tree (gimple_omp_parallel_data_arg_ptr (stmt), callback_op,
 358                        wi, pset);
 359       if (ret)
 360         return ret;
 361       break;
 362
 363     case GIMPLE_OMP_TASK:
 364       ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
 365                        wi, pset);
 366       if (ret)
 367         return ret;
 368       ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
 369                        wi, pset);
 370       if (ret)
 371         return ret;
 372       ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
 373                        wi, pset);
 374       if (ret)
 375         return ret;
 376       ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
 377                        wi, pset);
 378       if (ret)
 379         return ret;
 380       ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
 381                        wi, pset);
 382       if (ret)
 383         return ret;
 384       ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
 385                        wi, pset);
 386       if (ret)
 387         return ret;
 388       break;
 389
 390     case GIMPLE_OMP_SECTIONS:
 391       ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
 392                        wi, pset);
 393       if (ret)
 394         return ret;
 395
 396       ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
 397                        wi, pset);
 398       if (ret)
 399         return ret;
 400
 401       break;
 402
 403     case GIMPLE_OMP_SINGLE:
 404       ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
 405                        pset);
 406       if (ret)
 407         return ret;
 408       break;
 409
 410     case GIMPLE_OMP_TARGET:
 411       ret = walk_tree (gimple_omp_target_clauses_ptr (stmt), callback_op, wi,
 412                        pset);
 413       if (ret)
 414         return ret;
 415       break;
 416
 417     case GIMPLE_OMP_TEAMS:
 418       ret = walk_tree (gimple_omp_teams_clauses_ptr (stmt), callback_op, wi,
 419                        pset);
 420       if (ret)
 421         return ret;
 422       break;
 423
 424     case GIMPLE_OMP_ATOMIC_LOAD:
 425       {
 426         gimple_omp_atomic_load omp_stmt = as_a <gimple_omp_atomic_load> (stmt);
 427         ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (omp_stmt),
 428                          callback_op, wi, pset);
 429         if (ret)
 430           return ret;
 431
 432         ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (omp_stmt),
 433                          callback_op, wi, pset);
 434         if (ret)
 435           return ret;
 436       }
 437       break;
 438
 439     case GIMPLE_OMP_ATOMIC_STORE:
 440       ret = walk_tree (gimple_omp_atomic_store_val_ptr (
 441                          as_a <gimple_omp_atomic_store> (stmt)),
 442                        callback_op, wi, pset);
 443       if (ret)
 444         return ret;
 445       break;
 446
 447     case GIMPLE_TRANSACTION:
 448       ret = walk_tree (gimple_transaction_label_ptr (
 449                          as_a <gimple_transaction> (stmt)),
 450                        callback_op, wi, pset);
 451       if (ret)
 452         return ret;
 453       break;
 454
 455     case GIMPLE_OMP_RETURN:
 456       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 457                        pset);
 458       if (ret)
 459         return ret;
 460       break;
 461
 462       /* Tuples that do not have operands.  */
 463     case GIMPLE_NOP:
 464     case GIMPLE_RESX:
 465     case GIMPLE_PREDICT:
 466       break;
 467
 468     default:
 469       {
 470         enum gimple_statement_structure_enum gss;
 471         gss = gimple_statement_structure (stmt);
 472         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 473           for (i = 0; i < gimple_num_ops (stmt); i++)
 474             {
 475               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 476               if (ret)
 477                 return ret;
 478             }
 479       }
 480       break;
 481     }
 482
 483   return NULL_TREE;
 484 }
 485
 486
 487 /* Walk the current statement in GSI (optionally using traversal state
 488    stored in WI).  If WI is NULL, no state is kept during traversal.
 489    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 490    that it has handled all the operands of the statement, its return
 491    value is returned.  Otherwise, the return value from CALLBACK_STMT
 492    is discarded and its operands are scanned.
 493
 494    If CALLBACK_STMT is NULL or it didn't handle the operands,
 495    CALLBACK_OP is called on each operand of the statement via
 496    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 497    operand, the remaining operands are not scanned.  In this case, the
 498    return value from CALLBACK_OP is returned.
 499
 500    In any other case, NULL_TREE is returned.  */
 501
 502 tree
 503 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 504                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 505 {
 506   gimple ret;
 507   tree tree_ret;
 508   gimple stmt = gsi_stmt (*gsi);
 509
 510   if (wi)
 511     {
 512       wi->gsi = *gsi;
 513       wi->removed_stmt = false;
 514
 515       if (wi->want_locations && gimple_has_location (stmt))
 516         input_location = gimple_location (stmt);
 517     }
 518
 519   ret = NULL;
 520
 521   /* Invoke the statement callback.  Return if the callback handled
 522      all of STMT operands by itself.  */
 523   if (callback_stmt)
 524     {
 525       bool handled_ops = false;
 526       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 527       if (handled_ops)
 528         return tree_ret;
 529
 530       /* If CALLBACK_STMT did not handle operands, it should not have
 531          a value to return.  */
 532       gcc_assert (tree_ret == NULL);
 533
 534       if (wi && wi->removed_stmt)
 535         return NULL;
 536
 537       /* Re-read stmt in case the callback changed it.  */
 538       stmt = gsi_stmt (*gsi);
 539     }
 540
 541   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 542   if (callback_op)
 543     {
 544       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 545       if (tree_ret)
 546         return tree_ret;
 547     }
 548
 549   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 550   switch (gimple_code (stmt))
 551     {
 552     case GIMPLE_BIND:
 553       ret =
 554         walk_gimple_seq_mod (gimple_bind_body_ptr (as_a <gimple_bind> (stmt)),
 555                              callback_stmt, callback_op, wi);
 556       if (ret)
 557         return wi->callback_result;
 558       break;
 559
 560     case GIMPLE_CATCH:
 561       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (
 562                                    as_a <gimple_catch> (stmt)),
 563                                  callback_stmt, callback_op, wi);
 564       if (ret)
 565         return wi->callback_result;
 566       break;
 567
 568     case GIMPLE_EH_FILTER:
 569       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 570                              callback_op, wi);
 571       if (ret)
 572         return wi->callback_result;
 573       break;
 574
 575     case GIMPLE_EH_ELSE:
 576       {
 577         gimple_eh_else eh_else_stmt = as_a <gimple_eh_else> (stmt);
 578         ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (eh_else_stmt),
 579                                    callback_stmt, callback_op, wi);
 580         if (ret)
 581           return wi->callback_result;
 582         ret = walk_gimple_seq_mod (gimple_eh_else_e_body_ptr (eh_else_stmt),
 583                                    callback_stmt, callback_op, wi);
 584         if (ret)
 585           return wi->callback_result;
 586       }
 587       break;
 588
 589     case GIMPLE_TRY:
 590       ret = walk_gimple_seq_mod (gimple_try_eval_ptr (stmt), callback_stmt, callback_op,
 591                              wi);
 592       if (ret)
 593         return wi->callback_result;
 594
 595       ret = walk_gimple_seq_mod (gimple_try_cleanup_ptr (stmt), callback_stmt,
 596                              callback_op, wi);
 597       if (ret)
 598         return wi->callback_result;
 599       break;
 600
 601     case GIMPLE_OMP_FOR:
 602       ret = walk_gimple_seq_mod (gimple_omp_for_pre_body_ptr (stmt), callback_stmt,
 603                              callback_op, wi);
 604       if (ret)
 605         return wi->callback_result;
 606
 607       /* FALL THROUGH.  */
 608     case GIMPLE_OMP_CRITICAL:
 609     case GIMPLE_OMP_MASTER:
 610     case GIMPLE_OMP_TASKGROUP:
 611     case GIMPLE_OMP_ORDERED:
 612     case GIMPLE_OMP_SECTION:
 613     case GIMPLE_OMP_PARALLEL:
 614     case GIMPLE_OMP_TASK:
 615     case GIMPLE_OMP_SECTIONS:
 616     case GIMPLE_OMP_SINGLE:
 617     case GIMPLE_OMP_TARGET:
 618     case GIMPLE_OMP_TEAMS:
 619       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 620                              callback_op, wi);
 621       if (ret)
 622         return wi->callback_result;
 623       break;
 624
 625     case GIMPLE_WITH_CLEANUP_EXPR:
 626       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 627                              callback_op, wi);
 628       if (ret)
 629         return wi->callback_result;
 630       break;
 631
 632     case GIMPLE_TRANSACTION:
 633       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (
 634                                    as_a <gimple_transaction> (stmt)),
 635                              callback_stmt, callback_op, wi);
 636       if (ret)
 637         return wi->callback_result;
 638       break;
 639
 640     default:
 641       gcc_assert (!gimple_has_substatements (stmt));
 642       break;
 643     }
 644
 645   return NULL;
 646 }
 647
 648 /* From a tree operand OP return the base of a load or store operation
 649    or NULL_TREE if OP is not a load or a store.  */
 650
 651 static tree
 652 get_base_loadstore (tree op)
 653 {
 654   while (handled_component_p (op))
 655     op = TREE_OPERAND (op, 0);
 656   if (DECL_P (op)
 657       || INDIRECT_REF_P (op)
 658       || TREE_CODE (op) == MEM_REF
 659       || TREE_CODE (op) == TARGET_MEM_REF)
 660     return op;
 661   return NULL_TREE;
 662 }
 663
 664
 665 /* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
 666    VISIT_ADDR if non-NULL on loads, store and address-taken operands
 667    passing the STMT, the base of the operand, the operand itself containing
 668    the base and DATA to it.  The base will be either a decl, an indirect
 669    reference (including TARGET_MEM_REF) or the argument of an address
 670    expression.
 671    Returns the results of these callbacks or'ed.  */
 672
 673 bool
 674 walk_stmt_load_store_addr_ops (gimple stmt, void *data,
 675                                walk_stmt_load_store_addr_fn visit_load,
 676                                walk_stmt_load_store_addr_fn visit_store,
 677                                walk_stmt_load_store_addr_fn visit_addr)
 678 {
 679   bool ret = false;
 680   unsigned i;
 681   if (gimple_assign_single_p (stmt))
 682     {
 683       tree lhs, rhs, arg;
 684       if (visit_store)
 685         {
 686           arg = gimple_assign_lhs (stmt);
 687           lhs = get_base_loadstore (arg);
 688           if (lhs)
 689             ret |= visit_store (stmt, lhs, arg, data);
 690         }
 691       arg = gimple_assign_rhs1 (stmt);
 692       rhs = arg;
 693       while (handled_component_p (rhs))
 694         rhs = TREE_OPERAND (rhs, 0);
 695       if (visit_addr)
 696         {
 697           if (TREE_CODE (rhs) == ADDR_EXPR)
 698             ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), arg, data);
 699           else if (TREE_CODE (rhs) == TARGET_MEM_REF
 700                    && TREE_CODE (TMR_BASE (rhs)) == ADDR_EXPR)
 701             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (rhs), 0), arg,
 702                                data);
 703           else if (TREE_CODE (rhs) == OBJ_TYPE_REF
 704                    && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
 705             ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
 706                                                    0), arg, data);
 707           else if (TREE_CODE (rhs) == CONSTRUCTOR)
 708             {
 709               unsigned int ix;
 710               tree val;
 711
 712               FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), ix, val)
 713                 if (TREE_CODE (val) == ADDR_EXPR)
 714                   ret |= visit_addr (stmt, TREE_OPERAND (val, 0), arg, data);
 715                 else if (TREE_CODE (val) == OBJ_TYPE_REF
 716                          && TREE_CODE (OBJ_TYPE_REF_OBJECT (val)) == ADDR_EXPR)
 717                   ret |= visit_addr (stmt,
 718                                      TREE_OPERAND (OBJ_TYPE_REF_OBJECT (val),
 719                                                    0), arg, data);
 720             }
 721           lhs = gimple_assign_lhs (stmt);
 722           if (TREE_CODE (lhs) == TARGET_MEM_REF
 723               && TREE_CODE (TMR_BASE (lhs)) == ADDR_EXPR)
 724             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (lhs), 0), lhs, data);
 725         }
 726       if (visit_load)
 727         {
 728           rhs = get_base_loadstore (rhs);
 729           if (rhs)
 730             ret |= visit_load (stmt, rhs, arg, data);
 731         }
 732     }
 733   else if (visit_addr
 734            && (is_gimple_assign (stmt)
 735                || gimple_code (stmt) == GIMPLE_COND))
 736     {
 737       for (i = 0; i < gimple_num_ops (stmt); ++i)
 738         {
 739           tree op = gimple_op (stmt, i);
 740           if (op == NULL_TREE)
 741             ;
 742           else if (TREE_CODE (op) == ADDR_EXPR)
 743             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 744           /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
 745              tree with two operands.  */
 746           else if (i == 1 && COMPARISON_CLASS_P (op))
 747             {
 748               if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
 749                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
 750                                                        0), op, data);
 751               if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
 752                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
 753                                                        0), op, data);
 754             }
 755         }
 756     }
 757   else if (is_gimple_call (stmt))
 758     {
 759       if (visit_store)
 760         {
 761           tree arg = gimple_call_lhs (stmt);
 762           if (arg)
 763             {
 764               tree lhs = get_base_loadstore (arg);
 765               if (lhs)
 766                 ret |= visit_store (stmt, lhs, arg, data);
 767             }
 768         }
 769       if (visit_load || visit_addr)
 770         for (i = 0; i < gimple_call_num_args (stmt); ++i)
 771           {
 772             tree arg = gimple_call_arg (stmt, i);
 773             if (visit_addr
 774                 && TREE_CODE (arg) == ADDR_EXPR)
 775               ret |= visit_addr (stmt, TREE_OPERAND (arg, 0), arg, data);
 776             else if (visit_load)
 777               {
 778                 tree rhs = get_base_loadstore (arg);
 779                 if (rhs)
 780                   ret |= visit_load (stmt, rhs, arg, data);
 781               }
 782           }
 783       if (visit_addr
 784           && gimple_call_chain (stmt)
 785           && TREE_CODE (gimple_call_chain (stmt)) == ADDR_EXPR)
 786         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (stmt), 0),
 787                            gimple_call_chain (stmt), data);
 788       if (visit_addr
 789           && gimple_call_return_slot_opt_p (stmt)
 790           && gimple_call_lhs (stmt) != NULL_TREE
 791           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt))))
 792         ret |= visit_addr (stmt, gimple_call_lhs (stmt),
 793                            gimple_call_lhs (stmt), data);
 794     }
 795   else if (gimple_asm asm_stmt = dyn_cast <gimple_asm> (stmt))
 796     {
 797       unsigned noutputs;
 798       const char *constraint;
 799       const char **oconstraints;
 800       bool allows_mem, allows_reg, is_inout;
 801       noutputs = gimple_asm_noutputs (asm_stmt);
 802       oconstraints = XALLOCAVEC (const char *, noutputs);
 803       if (visit_store || visit_addr)
 804         for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
 805           {
 806             tree link = gimple_asm_output_op (asm_stmt, i);
 807             tree op = get_base_loadstore (TREE_VALUE (link));
 808             if (op && visit_store)
 809               ret |= visit_store (stmt, op, TREE_VALUE (link), data);
 810             if (visit_addr)
 811               {
 812                 constraint = TREE_STRING_POINTER
 813                     (TREE_VALUE (TREE_PURPOSE (link)));
 814                 oconstraints[i] = constraint;
 815                 parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 816                                          &allows_reg, &is_inout);
 817                 if (op && !allows_reg && allows_mem)
 818                   ret |= visit_addr (stmt, op, TREE_VALUE (link), data);
 819               }
 820           }
 821       if (visit_load || visit_addr)
 822         for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
 823           {
 824             tree link = gimple_asm_input_op (asm_stmt, i);
 825             tree op = TREE_VALUE (link);
 826             if (visit_addr
 827                 && TREE_CODE (op) == ADDR_EXPR)
 828               ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 829             else if (visit_load || visit_addr)
 830               {
 831                 op = get_base_loadstore (op);
 832                 if (op)
 833                   {
 834                     if (visit_load)
 835                       ret |= visit_load (stmt, op, TREE_VALUE (link), data);
 836                     if (visit_addr)
 837                       {
 838                         constraint = TREE_STRING_POINTER
 839                             (TREE_VALUE (TREE_PURPOSE (link)));
 840                         parse_input_constraint (&constraint, 0, 0, noutputs,
 841                                                 0, oconstraints,
 842                                                 &allows_mem, &allows_reg);
 843                         if (!allows_reg && allows_mem)
 844                           ret |= visit_addr (stmt, op, TREE_VALUE (link),
 845                                              data);
 846                       }
 847                   }
 848               }
 849           }
 850     }
 851   else if (gimple_code (stmt) == GIMPLE_RETURN)
 852     {
 853       tree op = gimple_return_retval (stmt);
 854       if (op)
 855         {
 856           if (visit_addr
 857               && TREE_CODE (op) == ADDR_EXPR)
 858             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 859           else if (visit_load)
 860             {
 861               tree base = get_base_loadstore (op);
 862               if (base)
 863                 ret |= visit_load (stmt, base, op, data);
 864             }
 865         }
 866     }
 867   else if (visit_addr
 868            && gimple_code (stmt) == GIMPLE_PHI)
 869     {
 870       for (i = 0; i < gimple_phi_num_args (stmt); ++i)
 871         {
 872           tree op = gimple_phi_arg_def (stmt, i);
 873           if (TREE_CODE (op) == ADDR_EXPR)
 874             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 875         }
 876     }
 877   else if (visit_addr
 878            && gimple_code (stmt) == GIMPLE_GOTO)
 879     {
 880       tree op = gimple_goto_dest (stmt);
 881       if (TREE_CODE (op) == ADDR_EXPR)
 882         ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 883     }
 884
 885   return ret;
 886 }
 887
 888 /* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
 889    should make a faster clone for this case.  */
 890
 891 bool
 892 walk_stmt_load_store_ops (gimple stmt, void *data,
 893                           walk_stmt_load_store_addr_fn visit_load,
 894                           walk_stmt_load_store_addr_fn visit_store)
 895 {
 896   return walk_stmt_load_store_addr_ops (stmt, data,
 897                                         visit_load, visit_store, NULL);
 898 }