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