gcc/gimple-walk.c

   1 /* Gimple walk support.
   2
   3    Copyright (C) 2007-2015 Free Software Foundation, Inc.
   4    Contributed by Aldy Hernandez <aldyh@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "hash-set.h"
  27 #include "vec.h"
  28 #include "double-int.h"
  29 #include "input.h"
  30 #include "alias.h"
  31 #include "symtab.h"
  32 #include "inchash.h"
  33 #include "tree.h"
  34 #include "predict.h"
  35 #include "hard-reg-set.h"
  36 #include "function.h"
  37 #include "gimple-expr.h"
  38 #include "is-a.h"
  39 #include "tree-ssa-alias.h"
  40 #include "basic-block.h"
  41 #include "fold-const.h"
  42 #include "gimple.h"
  43 #include "gimple-iterator.h"
  44 #include "gimple-walk.h"
  45 #include "stmt.h"
  46
  47 /* Walk all the statements in the sequence *PSEQ calling walk_gimple_stmt
  48    on each one.  WI is as in walk_gimple_stmt.
  49
  50    If walk_gimple_stmt returns non-NULL, the walk is stopped, and the
  51    value is stored in WI->CALLBACK_RESULT.  Also, the statement that
  52    produced the value is returned if this statement has not been
  53    removed by a callback (wi->removed_stmt).  If the statement has
  54    been removed, NULL is returned.
  55
  56    Otherwise, all the statements are walked and NULL returned.  */
  57
  58 gimple
  59 walk_gimple_seq_mod (gimple_seq *pseq, walk_stmt_fn callback_stmt,
  60                      walk_tree_fn callback_op, struct walk_stmt_info *wi)
  61 {
  62   gimple_stmt_iterator gsi;
  63
  64   for (gsi = gsi_start (*pseq); !gsi_end_p (gsi); )
  65     {
  66       tree ret = walk_gimple_stmt (&gsi, callback_stmt, callback_op, wi);
  67       if (ret)
  68         {
  69           /* If CALLBACK_STMT or CALLBACK_OP return a value, WI must exist
  70              to hold it.  */
  71           gcc_assert (wi);
  72           wi->callback_result = ret;
  73
  74           return wi->removed_stmt ? NULL : gsi_stmt (gsi);
  75         }
  76
  77       if (!wi->removed_stmt)
  78         gsi_next (&gsi);
  79     }
  80
  81   if (wi)
  82     wi->callback_result = NULL_TREE;
  83
  84   return NULL;
  85 }
  86
  87
  88 /* Like walk_gimple_seq_mod, but ensure that the head of SEQ isn't
  89    changed by the callbacks.  */
  90
  91 gimple
  92 walk_gimple_seq (gimple_seq seq, walk_stmt_fn callback_stmt,
  93                  walk_tree_fn callback_op, struct walk_stmt_info *wi)
  94 {
  95   gimple_seq seq2 = seq;
  96   gimple ret = walk_gimple_seq_mod (&seq2, callback_stmt, callback_op, wi);
  97   gcc_assert (seq2 == seq);
  98   return ret;
  99 }
 100
 101
 102 /* Helper function for walk_gimple_stmt.  Walk operands of a GIMPLE_ASM.  */
 103
 104 static tree
 105 walk_gimple_asm (gasm *stmt, walk_tree_fn callback_op,
 106                  struct walk_stmt_info *wi)
 107 {
 108   tree ret, op;
 109   unsigned noutputs;
 110   const char **oconstraints;
 111   unsigned i, n;
 112   const char *constraint;
 113   bool allows_mem, allows_reg, is_inout;
 114
 115   noutputs = gimple_asm_noutputs (stmt);
 116   oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *));
 117
 118   if (wi)
 119     wi->is_lhs = true;
 120
 121   for (i = 0; i < noutputs; i++)
 122     {
 123       op = gimple_asm_output_op (stmt, i);
 124       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 125       oconstraints[i] = constraint;
 126       if (wi)
 127         {
 128           if (parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 129                                        &allows_reg, &is_inout))
 130             wi->val_only = (allows_reg || !allows_mem);
 131         }
 132       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 133       if (ret)
 134         return ret;
 135     }
 136
 137   n = gimple_asm_ninputs (stmt);
 138   for (i = 0; i < n; i++)
 139     {
 140       op = gimple_asm_input_op (stmt, i);
 141       constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
 142
 143       if (wi)
 144         {
 145           if (parse_input_constraint (&constraint, 0, 0, noutputs, 0,
 146                                       oconstraints, &allows_mem, &allows_reg))
 147             {
 148               wi->val_only = (allows_reg || !allows_mem);
 149               /* Although input "m" is not really a LHS, we need a lvalue.  */
 150               wi->is_lhs = !wi->val_only;
 151             }
 152         }
 153       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 154       if (ret)
 155         return ret;
 156     }
 157
 158   if (wi)
 159     {
 160       wi->is_lhs = false;
 161       wi->val_only = true;
 162     }
 163
 164   n = gimple_asm_nlabels (stmt);
 165   for (i = 0; i < n; i++)
 166     {
 167       op = gimple_asm_label_op (stmt, i);
 168       ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
 169       if (ret)
 170         return ret;
 171     }
 172
 173   return NULL_TREE;
 174 }
 175
 176
 177 /* Helper function of WALK_GIMPLE_STMT.  Walk every tree operand in
 178    STMT.  CALLBACK_OP and WI are as in WALK_GIMPLE_STMT.
 179
 180    CALLBACK_OP is called on each operand of STMT via walk_tree.
 181    Additional parameters to walk_tree must be stored in WI.  For each operand
 182    OP, walk_tree is called as:
 183
 184         walk_tree (&OP, CALLBACK_OP, WI, WI->PSET)
 185
 186    If CALLBACK_OP returns non-NULL for an operand, the remaining
 187    operands are not scanned.
 188
 189    The return value is that returned by the last call to walk_tree, or
 190    NULL_TREE if no CALLBACK_OP is specified.  */
 191
 192 tree
 193 walk_gimple_op (gimple stmt, walk_tree_fn callback_op,
 194                 struct walk_stmt_info *wi)
 195 {
 196   hash_set<tree> *pset = (wi) ? wi->pset : NULL;
 197   unsigned i;
 198   tree ret = NULL_TREE;
 199
 200   switch (gimple_code (stmt))
 201     {
 202     case GIMPLE_ASSIGN:
 203       /* Walk the RHS operands.  If the LHS is of a non-renamable type or
 204          is a register variable, we may use a COMPONENT_REF on the RHS.  */
 205       if (wi)
 206         {
 207           tree lhs = gimple_assign_lhs (stmt);
 208           wi->val_only
 209             = (is_gimple_reg_type (TREE_TYPE (lhs)) && !is_gimple_reg (lhs))
 210               || gimple_assign_rhs_class (stmt) != GIMPLE_SINGLE_RHS;
 211         }
 212
 213       for (i = 1; i < gimple_num_ops (stmt); i++)
 214         {
 215           ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi,
 216                            pset);
 217           if (ret)
 218             return ret;
 219         }
 220
 221       /* Walk the LHS.  If the RHS is appropriate for a memory, we
 222          may use a COMPONENT_REF on the LHS.  */
 223       if (wi)
 224         {
 225           /* If the RHS is of a non-renamable type or is a register variable,
 226              we may use a COMPONENT_REF on the LHS.  */
 227           tree rhs1 = gimple_assign_rhs1 (stmt);
 228           wi->val_only
 229             = (is_gimple_reg_type (TREE_TYPE (rhs1)) && !is_gimple_reg (rhs1))
 230               || gimple_assign_rhs_class (stmt) != GIMPLE_SINGLE_RHS;
 231           wi->is_lhs = true;
 232         }
 233
 234       ret = walk_tree (gimple_op_ptr (stmt, 0), callback_op, wi, pset);
 235       if (ret)
 236         return ret;
 237
 238       if (wi)
 239         {
 240           wi->val_only = true;
 241           wi->is_lhs = false;
 242         }
 243       break;
 244
 245     case GIMPLE_CALL:
 246       if (wi)
 247         {
 248           wi->is_lhs = false;
 249           wi->val_only = true;
 250         }
 251
 252       ret = walk_tree (gimple_call_chain_ptr (as_a <gcall *> (stmt)),
 253                        callback_op, wi, pset);
 254       if (ret)
 255         return ret;
 256
 257       ret = walk_tree (gimple_call_fn_ptr (stmt), callback_op, wi, pset);
 258       if (ret)
 259         return ret;
 260
 261       for (i = 0; i < gimple_call_num_args (stmt); i++)
 262         {
 263           if (wi)
 264             wi->val_only
 265               = is_gimple_reg_type (TREE_TYPE (gimple_call_arg (stmt, i)));
 266           ret = walk_tree (gimple_call_arg_ptr (stmt, i), callback_op, wi,
 267                            pset);
 268           if (ret)
 269             return ret;
 270         }
 271
 272       if (gimple_call_lhs (stmt))
 273         {
 274           if (wi)
 275             {
 276               wi->is_lhs = true;
 277               wi->val_only
 278                 = is_gimple_reg_type (TREE_TYPE (gimple_call_lhs (stmt)));
 279             }
 280
 281           ret = walk_tree (gimple_call_lhs_ptr (stmt), callback_op, wi, pset);
 282           if (ret)
 283             return ret;
 284         }
 285
 286       if (wi)
 287         {
 288           wi->is_lhs = false;
 289           wi->val_only = true;
 290         }
 291       break;
 292
 293     case GIMPLE_CATCH:
 294       ret = walk_tree (gimple_catch_types_ptr (as_a <gcatch *> (stmt)),
 295                        callback_op, wi, pset);
 296       if (ret)
 297         return ret;
 298       break;
 299
 300     case GIMPLE_EH_FILTER:
 301       ret = walk_tree (gimple_eh_filter_types_ptr (stmt), callback_op, wi,
 302                        pset);
 303       if (ret)
 304         return ret;
 305       break;
 306
 307     case GIMPLE_ASM:
 308       ret = walk_gimple_asm (as_a <gasm *> (stmt), callback_op, wi);
 309       if (ret)
 310         return ret;
 311       break;
 312
 313     case GIMPLE_OMP_CONTINUE:
 314       {
 315         gomp_continue *cont_stmt = as_a <gomp_continue *> (stmt);
 316         ret = walk_tree (gimple_omp_continue_control_def_ptr (cont_stmt),
 317                          callback_op, wi, pset);
 318         if (ret)
 319           return ret;
 320
 321         ret = walk_tree (gimple_omp_continue_control_use_ptr (cont_stmt),
 322                          callback_op, wi, pset);
 323         if (ret)
 324           return ret;
 325       }
 326       break;
 327
 328     case GIMPLE_OMP_CRITICAL:
 329       {
 330         gomp_critical *omp_stmt = as_a <gomp_critical *> (stmt);
 331         ret = walk_tree (gimple_omp_critical_name_ptr (omp_stmt),
 332                          callback_op, wi, pset);
 333         if (ret)
 334           return ret;
 335       }
 336       break;
 337
 338     case GIMPLE_OMP_FOR:
 339       ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
 340                        pset);
 341       if (ret)
 342         return ret;
 343       for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
 344         {
 345           ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
 346                            wi, pset);
 347           if (ret)
 348             return ret;
 349           ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
 350                            wi, pset);
 351           if (ret)
 352             return ret;
 353           ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
 354                            wi, pset);
 355           if (ret)
 356             return ret;
 357           ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
 358                            wi, pset);
 359           if (ret)
 360             return ret;
 361         }
 362       break;
 363
 364     case GIMPLE_OMP_PARALLEL:
 365       {
 366         gomp_parallel *omp_par_stmt = as_a <gomp_parallel *> (stmt);
 367         ret = walk_tree (gimple_omp_parallel_clauses_ptr (omp_par_stmt),
 368                          callback_op, wi, pset);
 369         if (ret)
 370           return ret;
 371         ret = walk_tree (gimple_omp_parallel_child_fn_ptr (omp_par_stmt),
 372                          callback_op, wi, pset);
 373         if (ret)
 374           return ret;
 375         ret = walk_tree (gimple_omp_parallel_data_arg_ptr (omp_par_stmt),
 376                          callback_op, wi, pset);
 377         if (ret)
 378           return ret;
 379       }
 380       break;
 381
 382     case GIMPLE_OMP_TASK:
 383       ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
 384                        wi, pset);
 385       if (ret)
 386         return ret;
 387       ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
 388                        wi, pset);
 389       if (ret)
 390         return ret;
 391       ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
 392                        wi, pset);
 393       if (ret)
 394         return ret;
 395       ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
 396                        wi, pset);
 397       if (ret)
 398         return ret;
 399       ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
 400                        wi, pset);
 401       if (ret)
 402         return ret;
 403       ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
 404                        wi, pset);
 405       if (ret)
 406         return ret;
 407       break;
 408
 409     case GIMPLE_OMP_SECTIONS:
 410       ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
 411                        wi, pset);
 412       if (ret)
 413         return ret;
 414       ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
 415                        wi, pset);
 416       if (ret)
 417         return ret;
 418
 419       break;
 420
 421     case GIMPLE_OMP_SINGLE:
 422       ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
 423                        pset);
 424       if (ret)
 425         return ret;
 426       break;
 427
 428     case GIMPLE_OMP_TARGET:
 429       {
 430         gomp_target *omp_stmt = as_a <gomp_target *> (stmt);
 431         ret = walk_tree (gimple_omp_target_clauses_ptr (omp_stmt),
 432                          callback_op, wi, pset);
 433         if (ret)
 434           return ret;
 435         ret = walk_tree (gimple_omp_target_child_fn_ptr (omp_stmt),
 436                          callback_op, wi, pset);
 437         if (ret)
 438           return ret;
 439         ret = walk_tree (gimple_omp_target_data_arg_ptr (omp_stmt),
 440                          callback_op, wi, pset);
 441         if (ret)
 442           return ret;
 443       }
 444       break;
 445
 446     case GIMPLE_OMP_TEAMS:
 447       ret = walk_tree (gimple_omp_teams_clauses_ptr (stmt), callback_op, wi,
 448                        pset);
 449       if (ret)
 450         return ret;
 451       break;
 452
 453     case GIMPLE_OMP_ATOMIC_LOAD:
 454       {
 455         gomp_atomic_load *omp_stmt = as_a <gomp_atomic_load *> (stmt);
 456         ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (omp_stmt),
 457                          callback_op, wi, pset);
 458         if (ret)
 459           return ret;
 460         ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (omp_stmt),
 461                          callback_op, wi, pset);
 462         if (ret)
 463           return ret;
 464       }
 465       break;
 466
 467     case GIMPLE_OMP_ATOMIC_STORE:
 468       {
 469         gomp_atomic_store *omp_stmt = as_a <gomp_atomic_store *> (stmt);
 470         ret = walk_tree (gimple_omp_atomic_store_val_ptr (omp_stmt),
 471                          callback_op, wi, pset);
 472         if (ret)
 473           return ret;
 474       }
 475       break;
 476
 477     case GIMPLE_TRANSACTION:
 478       ret = walk_tree (gimple_transaction_label_ptr (
 479                          as_a <gtransaction *> (stmt)),
 480                        callback_op, wi, pset);
 481       if (ret)
 482         return ret;
 483       break;
 484
 485     case GIMPLE_OMP_RETURN:
 486       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 487                        pset);
 488       if (ret)
 489         return ret;
 490       break;
 491
 492       /* Tuples that do not have operands.  */
 493     case GIMPLE_NOP:
 494     case GIMPLE_RESX:
 495     case GIMPLE_PREDICT:
 496       break;
 497
 498     default:
 499       {
 500         enum gimple_statement_structure_enum gss;
 501         gss = gimple_statement_structure (stmt);
 502         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 503           for (i = 0; i < gimple_num_ops (stmt); i++)
 504             {
 505               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 506               if (ret)
 507                 return ret;
 508             }
 509       }
 510       break;
 511     }
 512
 513   return NULL_TREE;
 514 }
 515
 516
 517 /* Walk the current statement in GSI (optionally using traversal state
 518    stored in WI).  If WI is NULL, no state is kept during traversal.
 519    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 520    that it has handled all the operands of the statement, its return
 521    value is returned.  Otherwise, the return value from CALLBACK_STMT
 522    is discarded and its operands are scanned.
 523
 524    If CALLBACK_STMT is NULL or it didn't handle the operands,
 525    CALLBACK_OP is called on each operand of the statement via
 526    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 527    operand, the remaining operands are not scanned.  In this case, the
 528    return value from CALLBACK_OP is returned.
 529
 530    In any other case, NULL_TREE is returned.  */
 531
 532 tree
 533 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 534                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 535 {
 536   gimple ret;
 537   tree tree_ret;
 538   gimple stmt = gsi_stmt (*gsi);
 539
 540   if (wi)
 541     {
 542       wi->gsi = *gsi;
 543       wi->removed_stmt = false;
 544
 545       if (wi->want_locations && gimple_has_location (stmt))
 546         input_location = gimple_location (stmt);
 547     }
 548
 549   ret = NULL;
 550
 551   /* Invoke the statement callback.  Return if the callback handled
 552      all of STMT operands by itself.  */
 553   if (callback_stmt)
 554     {
 555       bool handled_ops = false;
 556       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 557       if (handled_ops)
 558         return tree_ret;
 559
 560       /* If CALLBACK_STMT did not handle operands, it should not have
 561          a value to return.  */
 562       gcc_assert (tree_ret == NULL);
 563
 564       if (wi && wi->removed_stmt)
 565         return NULL;
 566
 567       /* Re-read stmt in case the callback changed it.  */
 568       stmt = gsi_stmt (*gsi);
 569     }
 570
 571   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 572   if (callback_op)
 573     {
 574       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 575       if (tree_ret)
 576         return tree_ret;
 577     }
 578
 579   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 580   switch (gimple_code (stmt))
 581     {
 582     case GIMPLE_BIND:
 583       ret = walk_gimple_seq_mod (gimple_bind_body_ptr (as_a <gbind *> (stmt)),
 584                                  callback_stmt, callback_op, wi);
 585       if (ret)
 586         return wi->callback_result;
 587       break;
 588
 589     case GIMPLE_CATCH:
 590       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (
 591                                    as_a <gcatch *> (stmt)),
 592                                  callback_stmt, callback_op, wi);
 593       if (ret)
 594         return wi->callback_result;
 595       break;
 596
 597     case GIMPLE_EH_FILTER:
 598       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 599                              callback_op, wi);
 600       if (ret)
 601         return wi->callback_result;
 602       break;
 603
 604     case GIMPLE_EH_ELSE:
 605       {
 606         geh_else *eh_else_stmt = as_a <geh_else *> (stmt);
 607         ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (eh_else_stmt),
 608                                    callback_stmt, callback_op, wi);
 609         if (ret)
 610           return wi->callback_result;
 611         ret = walk_gimple_seq_mod (gimple_eh_else_e_body_ptr (eh_else_stmt),
 612                                    callback_stmt, callback_op, wi);
 613         if (ret)
 614           return wi->callback_result;
 615       }
 616       break;
 617
 618     case GIMPLE_TRY:
 619       ret = walk_gimple_seq_mod (gimple_try_eval_ptr (stmt), callback_stmt, callback_op,
 620                              wi);
 621       if (ret)
 622         return wi->callback_result;
 623
 624       ret = walk_gimple_seq_mod (gimple_try_cleanup_ptr (stmt), callback_stmt,
 625                              callback_op, wi);
 626       if (ret)
 627         return wi->callback_result;
 628       break;
 629
 630     case GIMPLE_OMP_FOR:
 631       ret = walk_gimple_seq_mod (gimple_omp_for_pre_body_ptr (stmt), callback_stmt,
 632                              callback_op, wi);
 633       if (ret)
 634         return wi->callback_result;
 635
 636       /* FALL THROUGH.  */
 637     case GIMPLE_OMP_CRITICAL:
 638     case GIMPLE_OMP_MASTER:
 639     case GIMPLE_OMP_TASKGROUP:
 640     case GIMPLE_OMP_ORDERED:
 641     case GIMPLE_OMP_SECTION:
 642     case GIMPLE_OMP_PARALLEL:
 643     case GIMPLE_OMP_TASK:
 644     case GIMPLE_OMP_SECTIONS:
 645     case GIMPLE_OMP_SINGLE:
 646     case GIMPLE_OMP_TARGET:
 647     case GIMPLE_OMP_TEAMS:
 648       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 649                              callback_op, wi);
 650       if (ret)
 651         return wi->callback_result;
 652       break;
 653
 654     case GIMPLE_WITH_CLEANUP_EXPR:
 655       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 656                              callback_op, wi);
 657       if (ret)
 658         return wi->callback_result;
 659       break;
 660
 661     case GIMPLE_TRANSACTION:
 662       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (
 663                                    as_a <gtransaction *> (stmt)),
 664                              callback_stmt, callback_op, wi);
 665       if (ret)
 666         return wi->callback_result;
 667       break;
 668
 669     default:
 670       gcc_assert (!gimple_has_substatements (stmt));
 671       break;
 672     }
 673
 674   return NULL;
 675 }
 676
 677 /* From a tree operand OP return the base of a load or store operation
 678    or NULL_TREE if OP is not a load or a store.  */
 679
 680 static tree
 681 get_base_loadstore (tree op)
 682 {
 683   while (handled_component_p (op))
 684     op = TREE_OPERAND (op, 0);
 685   if (DECL_P (op)
 686       || INDIRECT_REF_P (op)
 687       || TREE_CODE (op) == MEM_REF
 688       || TREE_CODE (op) == TARGET_MEM_REF)
 689     return op;
 690   return NULL_TREE;
 691 }
 692
 693
 694 /* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
 695    VISIT_ADDR if non-NULL on loads, store and address-taken operands
 696    passing the STMT, the base of the operand, the operand itself containing
 697    the base and DATA to it.  The base will be either a decl, an indirect
 698    reference (including TARGET_MEM_REF) or the argument of an address
 699    expression.
 700    Returns the results of these callbacks or'ed.  */
 701
 702 bool
 703 walk_stmt_load_store_addr_ops (gimple stmt, void *data,
 704                                walk_stmt_load_store_addr_fn visit_load,
 705                                walk_stmt_load_store_addr_fn visit_store,
 706                                walk_stmt_load_store_addr_fn visit_addr)
 707 {
 708   bool ret = false;
 709   unsigned i;
 710   if (gimple_assign_single_p (stmt))
 711     {
 712       tree lhs, rhs, arg;
 713       if (visit_store)
 714         {
 715           arg = gimple_assign_lhs (stmt);
 716           lhs = get_base_loadstore (arg);
 717           if (lhs)
 718             ret |= visit_store (stmt, lhs, arg, data);
 719         }
 720       arg = gimple_assign_rhs1 (stmt);
 721       rhs = arg;
 722       while (handled_component_p (rhs))
 723         rhs = TREE_OPERAND (rhs, 0);
 724       if (visit_addr)
 725         {
 726           if (TREE_CODE (rhs) == ADDR_EXPR)
 727             ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), arg, data);
 728           else if (TREE_CODE (rhs) == TARGET_MEM_REF
 729                    && TREE_CODE (TMR_BASE (rhs)) == ADDR_EXPR)
 730             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (rhs), 0), arg,
 731                                data);
 732           else if (TREE_CODE (rhs) == OBJ_TYPE_REF
 733                    && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
 734             ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
 735                                                    0), arg, data);
 736           else if (TREE_CODE (rhs) == CONSTRUCTOR)
 737             {
 738               unsigned int ix;
 739               tree val;
 740
 741               FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), ix, val)
 742                 if (TREE_CODE (val) == ADDR_EXPR)
 743                   ret |= visit_addr (stmt, TREE_OPERAND (val, 0), arg, data);
 744                 else if (TREE_CODE (val) == OBJ_TYPE_REF
 745                          && TREE_CODE (OBJ_TYPE_REF_OBJECT (val)) == ADDR_EXPR)
 746                   ret |= visit_addr (stmt,
 747                                      TREE_OPERAND (OBJ_TYPE_REF_OBJECT (val),
 748                                                    0), arg, data);
 749             }
 750           lhs = gimple_assign_lhs (stmt);
 751           if (TREE_CODE (lhs) == TARGET_MEM_REF
 752               && TREE_CODE (TMR_BASE (lhs)) == ADDR_EXPR)
 753             ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (lhs), 0), lhs, data);
 754         }
 755       if (visit_load)
 756         {
 757           rhs = get_base_loadstore (rhs);
 758           if (rhs)
 759             ret |= visit_load (stmt, rhs, arg, data);
 760         }
 761     }
 762   else if (visit_addr
 763            && (is_gimple_assign (stmt)
 764                || gimple_code (stmt) == GIMPLE_COND))
 765     {
 766       for (i = 0; i < gimple_num_ops (stmt); ++i)
 767         {
 768           tree op = gimple_op (stmt, i);
 769           if (op == NULL_TREE)
 770             ;
 771           else if (TREE_CODE (op) == ADDR_EXPR)
 772             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 773           /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
 774              tree with two operands.  */
 775           else if (i == 1 && COMPARISON_CLASS_P (op))
 776             {
 777               if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
 778                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
 779                                                        0), op, data);
 780               if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
 781                 ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
 782                                                        0), op, data);
 783             }
 784         }
 785     }
 786   else if (gcall *call_stmt = dyn_cast <gcall *> (stmt))
 787     {
 788       if (visit_store)
 789         {
 790           tree arg = gimple_call_lhs (call_stmt);
 791           if (arg)
 792             {
 793               tree lhs = get_base_loadstore (arg);
 794               if (lhs)
 795                 ret |= visit_store (stmt, lhs, arg, data);
 796             }
 797         }
 798       if (visit_load || visit_addr)
 799         for (i = 0; i < gimple_call_num_args (call_stmt); ++i)
 800           {
 801             tree arg = gimple_call_arg (call_stmt, i);
 802             if (visit_addr
 803                 && TREE_CODE (arg) == ADDR_EXPR)
 804               ret |= visit_addr (stmt, TREE_OPERAND (arg, 0), arg, data);
 805             else if (visit_load)
 806               {
 807                 tree rhs = get_base_loadstore (arg);
 808                 if (rhs)
 809                   ret |= visit_load (stmt, rhs, arg, data);
 810               }
 811           }
 812       if (visit_addr
 813           && gimple_call_chain (call_stmt)
 814           && TREE_CODE (gimple_call_chain (call_stmt)) == ADDR_EXPR)
 815         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (call_stmt), 0),
 816                            gimple_call_chain (call_stmt), data);
 817       if (visit_addr
 818           && gimple_call_return_slot_opt_p (call_stmt)
 819           && gimple_call_lhs (call_stmt) != NULL_TREE
 820           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (call_stmt))))
 821         ret |= visit_addr (stmt, gimple_call_lhs (call_stmt),
 822                            gimple_call_lhs (call_stmt), data);
 823     }
 824   else if (gasm *asm_stmt = dyn_cast <gasm *> (stmt))
 825     {
 826       unsigned noutputs;
 827       const char *constraint;
 828       const char **oconstraints;
 829       bool allows_mem, allows_reg, is_inout;
 830       noutputs = gimple_asm_noutputs (asm_stmt);
 831       oconstraints = XALLOCAVEC (const char *, noutputs);
 832       if (visit_store || visit_addr)
 833         for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
 834           {
 835             tree link = gimple_asm_output_op (asm_stmt, i);
 836             tree op = get_base_loadstore (TREE_VALUE (link));
 837             if (op && visit_store)
 838               ret |= visit_store (stmt, op, TREE_VALUE (link), data);
 839             if (visit_addr)
 840               {
 841                 constraint = TREE_STRING_POINTER
 842                     (TREE_VALUE (TREE_PURPOSE (link)));
 843                 oconstraints[i] = constraint;
 844                 parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
 845                                          &allows_reg, &is_inout);
 846                 if (op && !allows_reg && allows_mem)
 847                   ret |= visit_addr (stmt, op, TREE_VALUE (link), data);
 848               }
 849           }
 850       if (visit_load || visit_addr)
 851         for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
 852           {
 853             tree link = gimple_asm_input_op (asm_stmt, i);
 854             tree op = TREE_VALUE (link);
 855             if (visit_addr
 856                 && TREE_CODE (op) == ADDR_EXPR)
 857               ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 858             else if (visit_load || visit_addr)
 859               {
 860                 op = get_base_loadstore (op);
 861                 if (op)
 862                   {
 863                     if (visit_load)
 864                       ret |= visit_load (stmt, op, TREE_VALUE (link), data);
 865                     if (visit_addr)
 866                       {
 867                         constraint = TREE_STRING_POINTER
 868                             (TREE_VALUE (TREE_PURPOSE (link)));
 869                         parse_input_constraint (&constraint, 0, 0, noutputs,
 870                                                 0, oconstraints,
 871                                                 &allows_mem, &allows_reg);
 872                         if (!allows_reg && allows_mem)
 873                           ret |= visit_addr (stmt, op, TREE_VALUE (link),
 874                                              data);
 875                       }
 876                   }
 877               }
 878           }
 879     }
 880   else if (greturn *return_stmt = dyn_cast <greturn *> (stmt))
 881     {
 882       tree op = gimple_return_retval (return_stmt);
 883       if (op)
 884         {
 885           if (visit_addr
 886               && TREE_CODE (op) == ADDR_EXPR)
 887             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 888           else if (visit_load)
 889             {
 890               tree base = get_base_loadstore (op);
 891               if (base)
 892                 ret |= visit_load (stmt, base, op, data);
 893             }
 894         }
 895     }
 896   else if (visit_addr
 897            && gimple_code (stmt) == GIMPLE_PHI)
 898     {
 899       for (i = 0; i < gimple_phi_num_args (stmt); ++i)
 900         {
 901           tree op = gimple_phi_arg_def (stmt, i);
 902           if (TREE_CODE (op) == ADDR_EXPR)
 903             ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 904         }
 905     }
 906   else if (visit_addr
 907            && gimple_code (stmt) == GIMPLE_GOTO)
 908     {
 909       tree op = gimple_goto_dest (stmt);
 910       if (TREE_CODE (op) == ADDR_EXPR)
 911         ret |= visit_addr (stmt, TREE_OPERAND (op, 0), op, data);
 912     }
 913
 914   return ret;
 915 }
 916
 917 /* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
 918    should make a faster clone for this case.  */
 919
 920 bool
 921 walk_stmt_load_store_ops (gimple stmt, void *data,
 922                           walk_stmt_load_store_addr_fn visit_load,
 923                           walk_stmt_load_store_addr_fn visit_store)
 924 {
 925   return walk_stmt_load_store_addr_ops (stmt, data,
 926                                         visit_load, visit_store, NULL);
 927 }