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 (gimple 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 (stmt), callback_op, wi, pset);
 248       if (ret)
 249         return ret;
 250
 251       ret = walk_tree (gimple_call_fn_ptr (stmt), callback_op, wi, pset);
 252       if (ret)
 253         return ret;
 254
 255       for (i = 0; i < gimple_call_num_args (stmt); i++)
 256         {
 257           if (wi)
 258             wi->val_only
 259               = is_gimple_reg_type (TREE_TYPE (gimple_call_arg (stmt, i)));
 260           ret = walk_tree (gimple_call_arg_ptr (stmt, i), callback_op, wi,
 261                            pset);
 262           if (ret)
 263             return ret;
 264         }
 265
 266       if (gimple_call_lhs (stmt))
 267         {
 268           if (wi)
 269             {
 270               wi->is_lhs = true;
 271               wi->val_only
 272                 = is_gimple_reg_type (TREE_TYPE (gimple_call_lhs (stmt)));
 273             }
 274
 275           ret = walk_tree (gimple_call_lhs_ptr (stmt), callback_op, wi, pset);
 276           if (ret)
 277             return ret;
 278         }
 279
 280       if (wi)
 281         {
 282           wi->is_lhs = false;
 283           wi->val_only = true;
 284         }
 285       break;
 286
 287     case GIMPLE_CATCH:
 288       ret = walk_tree (gimple_catch_types_ptr (stmt), callback_op, wi,
 289                        pset);
 290       if (ret)
 291         return ret;
 292       break;
 293
 294     case GIMPLE_EH_FILTER:
 295       ret = walk_tree (gimple_eh_filter_types_ptr (stmt), callback_op, wi,
 296                        pset);
 297       if (ret)
 298         return ret;
 299       break;
 300
 301     case GIMPLE_ASM:
 302       ret = walk_gimple_asm (stmt, callback_op, wi);
 303       if (ret)
 304         return ret;
 305       break;
 306
 307     case GIMPLE_OACC_KERNELS:
 308       ret = walk_tree (gimple_oacc_kernels_clauses_ptr (stmt), callback_op,
 309                        wi, pset);
 310       if (ret)
 311         return ret;
 312       ret = walk_tree (gimple_oacc_kernels_child_fn_ptr (stmt), callback_op,
 313                        wi, pset);
 314       if (ret)
 315         return ret;
 316       ret = walk_tree (gimple_oacc_kernels_data_arg_ptr (stmt), callback_op,
 317                        wi, pset);
 318       if (ret)
 319         return ret;
 320       break;
 321
 322     case GIMPLE_OACC_PARALLEL:
 323       ret = walk_tree (gimple_oacc_parallel_clauses_ptr (stmt), callback_op,
 324                        wi, pset);
 325       if (ret)
 326         return ret;
 327       ret = walk_tree (gimple_oacc_parallel_child_fn_ptr (stmt), callback_op,
 328                        wi, pset);
 329       if (ret)
 330         return ret;
 331       ret = walk_tree (gimple_oacc_parallel_data_arg_ptr (stmt), callback_op,
 332                        wi, pset);
 333       if (ret)
 334         return ret;
 335       break;
 336
 337     case GIMPLE_OMP_CONTINUE:
 338       ret = walk_tree (gimple_omp_continue_control_def_ptr (stmt),
 339                        callback_op, wi, pset);
 340       if (ret)
 341         return ret;
 342
 343       ret = walk_tree (gimple_omp_continue_control_use_ptr (stmt),
 344                        callback_op, wi, pset);
 345       if (ret)
 346         return ret;
 347       break;
 348
 349     case GIMPLE_OMP_CRITICAL:
 350       ret = walk_tree (gimple_omp_critical_name_ptr (stmt), callback_op, wi,
 351                        pset);
 352       if (ret)
 353         return ret;
 354       break;
 355
 356     case GIMPLE_OMP_FOR:
 357       ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
 358                        pset);
 359       if (ret)
 360         return ret;
 361       for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
 362         {
 363           ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
 364                            wi, pset);
 365           if (ret)
 366             return ret;
 367           ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
 368                            wi, pset);
 369           if (ret)
 370             return ret;
 371           ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
 372                            wi, pset);
 373           if (ret)
 374             return ret;
 375           ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
 376                            wi, pset);
 377         }
 378       if (ret)
 379         return ret;
 380       break;
 381
 382     case GIMPLE_OMP_PARALLEL:
 383       ret = walk_tree (gimple_omp_parallel_clauses_ptr (stmt), callback_op,
 384                        wi, pset);
 385       if (ret)
 386         return ret;
 387       ret = walk_tree (gimple_omp_parallel_child_fn_ptr (stmt), callback_op,
 388                        wi, pset);
 389       if (ret)
 390         return ret;
 391       ret = walk_tree (gimple_omp_parallel_data_arg_ptr (stmt), callback_op,
 392                        wi, pset);
 393       if (ret)
 394         return ret;
 395       break;
 396
 397     case GIMPLE_OMP_TASK:
 398       ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
 399                        wi, pset);
 400       if (ret)
 401         return ret;
 402       ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
 403                        wi, pset);
 404       if (ret)
 405         return ret;
 406       ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
 407                        wi, pset);
 408       if (ret)
 409         return ret;
 410       ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
 411                        wi, pset);
 412       if (ret)
 413         return ret;
 414       ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
 415                        wi, pset);
 416       if (ret)
 417         return ret;
 418       ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
 419                        wi, pset);
 420       if (ret)
 421         return ret;
 422       break;
 423
 424     case GIMPLE_OMP_SECTIONS:
 425       ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
 426                        wi, pset);
 427       if (ret)
 428         return ret;
 429
 430       ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
 431                        wi, pset);
 432       if (ret)
 433         return ret;
 434
 435       break;
 436
 437     case GIMPLE_OMP_SINGLE:
 438       ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
 439                        pset);
 440       if (ret)
 441         return ret;
 442       break;
 443
 444     case GIMPLE_OMP_TARGET:
 445       ret = walk_tree (gimple_omp_target_clauses_ptr (stmt), callback_op, wi,
 446                        pset);
 447       if (ret)
 448         return ret;
 449       break;
 450
 451     case GIMPLE_OMP_TEAMS:
 452       ret = walk_tree (gimple_omp_teams_clauses_ptr (stmt), callback_op, wi,
 453                        pset);
 454       if (ret)
 455         return ret;
 456       break;
 457
 458     case GIMPLE_OMP_ATOMIC_LOAD:
 459       ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (stmt), callback_op, wi,
 460                        pset);
 461       if (ret)
 462         return ret;
 463
 464       ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (stmt), callback_op, wi,
 465                        pset);
 466       if (ret)
 467         return ret;
 468       break;
 469
 470     case GIMPLE_OMP_ATOMIC_STORE:
 471       ret = walk_tree (gimple_omp_atomic_store_val_ptr (stmt), callback_op,
 472                        wi, pset);
 473       if (ret)
 474         return ret;
 475       break;
 476
 477     case GIMPLE_TRANSACTION:
 478       ret = walk_tree (gimple_transaction_label_ptr (stmt), callback_op,
 479                        wi, pset);
 480       if (ret)
 481         return ret;
 482       break;
 483
 484     case GIMPLE_OMP_RETURN:
 485       ret = walk_tree (gimple_omp_return_lhs_ptr (stmt), callback_op, wi,
 486                        pset);
 487       if (ret)
 488         return ret;
 489       break;
 490
 491       /* Tuples that do not have operands.  */
 492     case GIMPLE_NOP:
 493     case GIMPLE_RESX:
 494     case GIMPLE_PREDICT:
 495       break;
 496
 497     default:
 498       {
 499         enum gimple_statement_structure_enum gss;
 500         gss = gimple_statement_structure (stmt);
 501         if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
 502           for (i = 0; i < gimple_num_ops (stmt); i++)
 503             {
 504               ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
 505               if (ret)
 506                 return ret;
 507             }
 508       }
 509       break;
 510     }
 511
 512   return NULL_TREE;
 513 }
 514
 515
 516 /* Walk the current statement in GSI (optionally using traversal state
 517    stored in WI).  If WI is NULL, no state is kept during traversal.
 518    The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
 519    that it has handled all the operands of the statement, its return
 520    value is returned.  Otherwise, the return value from CALLBACK_STMT
 521    is discarded and its operands are scanned.
 522
 523    If CALLBACK_STMT is NULL or it didn't handle the operands,
 524    CALLBACK_OP is called on each operand of the statement via
 525    walk_gimple_op.  If walk_gimple_op returns non-NULL for any
 526    operand, the remaining operands are not scanned.  In this case, the
 527    return value from CALLBACK_OP is returned.
 528
 529    In any other case, NULL_TREE is returned.  */
 530
 531 tree
 532 walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
 533                   walk_tree_fn callback_op, struct walk_stmt_info *wi)
 534 {
 535   gimple ret;
 536   tree tree_ret;
 537   gimple stmt = gsi_stmt (*gsi);
 538
 539   if (wi)
 540     {
 541       wi->gsi = *gsi;
 542       wi->removed_stmt = false;
 543
 544       if (wi->want_locations && gimple_has_location (stmt))
 545         input_location = gimple_location (stmt);
 546     }
 547
 548   ret = NULL;
 549
 550   /* Invoke the statement callback.  Return if the callback handled
 551      all of STMT operands by itself.  */
 552   if (callback_stmt)
 553     {
 554       bool handled_ops = false;
 555       tree_ret = callback_stmt (gsi, &handled_ops, wi);
 556       if (handled_ops)
 557         return tree_ret;
 558
 559       /* If CALLBACK_STMT did not handle operands, it should not have
 560          a value to return.  */
 561       gcc_assert (tree_ret == NULL);
 562
 563       if (wi && wi->removed_stmt)
 564         return NULL;
 565
 566       /* Re-read stmt in case the callback changed it.  */
 567       stmt = gsi_stmt (*gsi);
 568     }
 569
 570   /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
 571   if (callback_op)
 572     {
 573       tree_ret = walk_gimple_op (stmt, callback_op, wi);
 574       if (tree_ret)
 575         return tree_ret;
 576     }
 577
 578   /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
 579   switch (gimple_code (stmt))
 580     {
 581     case GIMPLE_BIND:
 582       ret = walk_gimple_seq_mod (gimple_bind_body_ptr (stmt), callback_stmt,
 583                                  callback_op, wi);
 584       if (ret)
 585         return wi->callback_result;
 586       break;
 587
 588     case GIMPLE_CATCH:
 589       ret = walk_gimple_seq_mod (gimple_catch_handler_ptr (stmt), callback_stmt,
 590                                  callback_op, wi);
 591       if (ret)
 592         return wi->callback_result;
 593       break;
 594
 595     case GIMPLE_EH_FILTER:
 596       ret = walk_gimple_seq_mod (gimple_eh_filter_failure_ptr (stmt), callback_stmt,
 597                              callback_op, wi);
 598       if (ret)
 599         return wi->callback_result;
 600       break;
 601
 602     case GIMPLE_EH_ELSE:
 603       ret = walk_gimple_seq_mod (gimple_eh_else_n_body_ptr (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 (stmt),
 608                              callback_stmt, callback_op, wi);
 609       if (ret)
 610         return wi->callback_result;
 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_OACC_KERNELS:
 633     case GIMPLE_OACC_PARALLEL:
 634     case GIMPLE_OMP_CRITICAL:
 635     case GIMPLE_OMP_MASTER:
 636     case GIMPLE_OMP_TASKGROUP:
 637     case GIMPLE_OMP_ORDERED:
 638     case GIMPLE_OMP_SECTION:
 639     case GIMPLE_OMP_PARALLEL:
 640     case GIMPLE_OMP_TASK:
 641     case GIMPLE_OMP_SECTIONS:
 642     case GIMPLE_OMP_SINGLE:
 643     case GIMPLE_OMP_TARGET:
 644     case GIMPLE_OMP_TEAMS:
 645       ret = walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), callback_stmt,
 646                              callback_op, wi);
 647       if (ret)
 648         return wi->callback_result;
 649       break;
 650
 651     case GIMPLE_WITH_CLEANUP_EXPR:
 652       ret = walk_gimple_seq_mod (gimple_wce_cleanup_ptr (stmt), callback_stmt,
 653                              callback_op, wi);
 654       if (ret)
 655         return wi->callback_result;
 656       break;
 657
 658     case GIMPLE_TRANSACTION:
 659       ret = walk_gimple_seq_mod (gimple_transaction_body_ptr (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 (is_gimple_call (stmt))
 783     {
 784       if (visit_store)
 785         {
 786           tree arg = gimple_call_lhs (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 (stmt); ++i)
 796           {
 797             tree arg = gimple_call_arg (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 (stmt)
 810           && TREE_CODE (gimple_call_chain (stmt)) == ADDR_EXPR)
 811         ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (stmt), 0),
 812                            gimple_call_chain (stmt), data);
 813       if (visit_addr
 814           && gimple_call_return_slot_opt_p (stmt)
 815           && gimple_call_lhs (stmt) != NULL_TREE
 816           && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt))))
 817         ret |= visit_addr (stmt, gimple_call_lhs (stmt),
 818                            gimple_call_lhs (stmt), data);
 819     }
 820   else if (gimple_code (stmt) == GIMPLE_ASM)
 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 (stmt);
 827       oconstraints = XALLOCAVEC (const char *, noutputs);
 828       if (visit_store || visit_addr)
 829         for (i = 0; i < gimple_asm_noutputs (stmt); ++i)
 830           {
 831             tree link = gimple_asm_output_op (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 (stmt); ++i)
 848           {
 849             tree link = gimple_asm_input_op (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 (gimple_code (stmt) == GIMPLE_RETURN)
 877     {
 878       tree op = gimple_return_retval (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 }