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