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