gcc/passes.c

   1 /* Top level of GCC compilers (cc1, cc1plus, etc.)
   2    Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301, USA.  */
  21
  22 /* This is the top level of cc1/c++.
  23    It parses command args, opens files, invokes the various passes
  24    in the proper order, and counts the time used by each.
  25    Error messages and low-level interface to malloc also handled here.  */
  26
  27 #include "config.h"
  28 #undef FLOAT /* This is for hpux. They should change hpux.  */
  29 #undef FFS  /* Some systems define this in param.h.  */
  30 #include "system.h"
  31 #include "coretypes.h"
  32 #include "tm.h"
  33 #include <signal.h>
  34
  35 #ifdef HAVE_SYS_RESOURCE_H
  36 # include <sys/resource.h>
  37 #endif
  38
  39 #ifdef HAVE_SYS_TIMES_H
  40 # include <sys/times.h>
  41 #endif
  42
  43 #include "line-map.h"
  44 #include "input.h"
  45 #include "tree.h"
  46 #include "rtl.h"
  47 #include "tm_p.h"
  48 #include "flags.h"
  49 #include "insn-attr.h"
  50 #include "insn-config.h"
  51 #include "insn-flags.h"
  52 #include "hard-reg-set.h"
  53 #include "recog.h"
  54 #include "output.h"
  55 #include "except.h"
  56 #include "function.h"
  57 #include "toplev.h"
  58 #include "expr.h"
  59 #include "basic-block.h"
  60 #include "intl.h"
  61 #include "ggc.h"
  62 #include "graph.h"
  63 #include "regs.h"
  64 #include "timevar.h"
  65 #include "diagnostic.h"
  66 #include "params.h"
  67 #include "reload.h"
  68 #include "dwarf2asm.h"
  69 #include "integrate.h"
  70 #include "real.h"
  71 #include "debug.h"
  72 #include "target.h"
  73 #include "langhooks.h"
  74 #include "cfglayout.h"
  75 #include "cfgloop.h"
  76 #include "hosthooks.h"
  77 #include "cgraph.h"
  78 #include "opts.h"
  79 #include "coverage.h"
  80 #include "value-prof.h"
  81 #include "tree-inline.h"
  82 #include "tree-flow.h"
  83 #include "tree-pass.h"
  84 #include "tree-dump.h"
  85
  86 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
  87 #include "dwarf2out.h"
  88 #endif
  89
  90 #if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
  91 #include "dbxout.h"
  92 #endif
  93
  94 #ifdef SDB_DEBUGGING_INFO
  95 #include "sdbout.h"
  96 #endif
  97
  98 #ifdef XCOFF_DEBUGGING_INFO
  99 #include "xcoffout.h"           /* Needed for external data
 100                                    declarations for e.g. AIX 4.x.  */
 101 #endif
 102
 103 /* Global variables used to communicate with passes.  */
 104 int dump_flags;
 105 bool in_gimple_form;
 106
 107
 108 /* This is called from various places for FUNCTION_DECL, VAR_DECL,
 109    and TYPE_DECL nodes.
 110
 111    This does nothing for local (non-static) variables, unless the
 112    variable is a register variable with DECL_ASSEMBLER_NAME set.  In
 113    that case, or if the variable is not an automatic, it sets up the
 114    RTL and outputs any assembler code (label definition, storage
 115    allocation and initialization).
 116
 117    DECL is the declaration.  TOP_LEVEL is nonzero
 118    if this declaration is not within a function.  */
 119
 120 void
 121 rest_of_decl_compilation (tree decl,
 122                           int top_level,
 123                           int at_end)
 124 {
 125   /* We deferred calling assemble_alias so that we could collect
 126      other attributes such as visibility.  Emit the alias now.  */
 127   {
 128     tree alias;
 129     alias = lookup_attribute ("alias", DECL_ATTRIBUTES (decl));
 130     if (alias)
 131       {
 132         alias = TREE_VALUE (TREE_VALUE (alias));
 133         alias = get_identifier (TREE_STRING_POINTER (alias));
 134         assemble_alias (decl, alias);
 135       }
 136   }
 137
 138   /* Can't defer this, because it needs to happen before any
 139      later function definitions are processed.  */
 140   if (DECL_ASSEMBLER_NAME_SET_P (decl) && DECL_REGISTER (decl))
 141     make_decl_rtl (decl);
 142
 143   /* Forward declarations for nested functions are not "external",
 144      but we need to treat them as if they were.  */
 145   if (TREE_STATIC (decl) || DECL_EXTERNAL (decl)
 146       || TREE_CODE (decl) == FUNCTION_DECL)
 147     {
 148       timevar_push (TV_VARCONST);
 149
 150       /* Don't output anything when a tentative file-scope definition
 151          is seen.  But at end of compilation, do output code for them.
 152
 153          We do output all variables when unit-at-a-time is active and rely on
 154          callgraph code to defer them except for forward declarations
 155          (see gcc.c-torture/compile/920624-1.c) */
 156       if ((at_end
 157            || !DECL_DEFER_OUTPUT (decl)
 158            || DECL_INITIAL (decl))
 159           && !DECL_EXTERNAL (decl))
 160         {
 161           if (flag_unit_at_a_time && !cgraph_global_info_ready
 162               && TREE_CODE (decl) != FUNCTION_DECL)
 163             cgraph_varpool_finalize_decl (decl);
 164           else
 165             assemble_variable (decl, top_level, at_end, 0);
 166         }
 167
 168 #ifdef ASM_FINISH_DECLARE_OBJECT
 169       if (decl == last_assemble_variable_decl)
 170         {
 171           ASM_FINISH_DECLARE_OBJECT (asm_out_file, decl,
 172                                      top_level, at_end);
 173         }
 174 #endif
 175
 176       timevar_pop (TV_VARCONST);
 177     }
 178   else if (TREE_CODE (decl) == TYPE_DECL
 179            /* Like in rest_of_type_compilation, avoid confusing the debug
 180               information machinery when there are errors.  */
 181            && !(sorrycount || errorcount))
 182     {
 183       timevar_push (TV_SYMOUT);
 184       debug_hooks->type_decl (decl, !top_level);
 185       timevar_pop (TV_SYMOUT);
 186     }
 187
 188   /* Let cgraph know about the existence of variables.  */
 189   if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
 190     cgraph_varpool_node (decl);
 191 }
 192
 193 /* Called after finishing a record, union or enumeral type.  */
 194
 195 void
 196 rest_of_type_compilation (tree type, int toplev)
 197 {
 198   /* Avoid confusing the debug information machinery when there are
 199      errors.  */
 200   if (errorcount != 0 || sorrycount != 0)
 201     return;
 202
 203   timevar_push (TV_SYMOUT);
 204   debug_hooks->type_decl (TYPE_STUB_DECL (type), !toplev);
 205   timevar_pop (TV_SYMOUT);
 206 }
 207
 208 \f
 209
 210 void
 211 finish_optimization_passes (void)
 212 {
 213   enum tree_dump_index i;
 214   struct dump_file_info *dfi;
 215   char *name;
 216
 217   timevar_push (TV_DUMP);
 218   if (profile_arc_flag || flag_test_coverage || flag_branch_probabilities)
 219     {
 220       dump_file = dump_begin (pass_branch_prob.static_pass_number, NULL);
 221       end_branch_prob ();
 222       if (dump_file)
 223         dump_end (pass_branch_prob.static_pass_number, dump_file);
 224     }
 225
 226   if (optimize > 0)
 227     {
 228       dump_file = dump_begin (pass_combine.static_pass_number, NULL);
 229       if (dump_file)
 230         {
 231           dump_combine_total_stats (dump_file);
 232           dump_end (pass_combine.static_pass_number, dump_file);
 233         }
 234     }
 235
 236   /* Do whatever is necessary to finish printing the graphs.  */
 237   if (graph_dump_format != no_graph)
 238     for (i = TDI_end; (dfi = get_dump_file_info (i)) != NULL; ++i)
 239       if (dump_initialized_p (i)
 240           && (dfi->flags & TDF_RTL) != 0
 241           && (name = get_dump_file_name (i)) != NULL)
 242         {
 243           finish_graph_dump_file (name);
 244           free (name);
 245         }
 246
 247   timevar_pop (TV_DUMP);
 248 }
 249
 250 static bool
 251 gate_rest_of_compilation (void)
 252 {
 253   /* Early return if there were errors.  We can run afoul of our
 254      consistency checks, and there's not really much point in fixing them.  */
 255   return !(rtl_dump_and_exit || flag_syntax_only || errorcount || sorrycount);
 256 }
 257
 258 struct tree_opt_pass pass_rest_of_compilation =
 259 {
 260   NULL,                                 /* name */
 261   gate_rest_of_compilation,             /* gate */
 262   NULL,                                 /* execute */
 263   NULL,                                 /* sub */
 264   NULL,                                 /* next */
 265   0,                                    /* static_pass_number */
 266   TV_REST_OF_COMPILATION,               /* tv_id */
 267   PROP_rtl,                             /* properties_required */
 268   0,                                    /* properties_provided */
 269   0,                                    /* properties_destroyed */
 270   0,                                    /* todo_flags_start */
 271   TODO_ggc_collect,                     /* todo_flags_finish */
 272   0                                     /* letter */
 273 };
 274
 275 static bool
 276 gate_postreload (void)
 277 {
 278   return reload_completed;
 279 }
 280
 281 struct tree_opt_pass pass_postreload =
 282 {
 283   NULL,                                 /* name */
 284   gate_postreload,                      /* gate */
 285   NULL,                                 /* execute */
 286   NULL,                                 /* sub */
 287   NULL,                                 /* next */
 288   0,                                    /* static_pass_number */
 289   0,                                    /* tv_id */
 290   PROP_rtl,                             /* properties_required */
 291   0,                                    /* properties_provided */
 292   0,                                    /* properties_destroyed */
 293   0,                                    /* todo_flags_start */
 294   TODO_ggc_collect,                     /* todo_flags_finish */
 295   0                                     /* letter */
 296 };
 297
 298
 299
 300 /* The root of the compilation pass tree, once constructed.  */
 301 struct tree_opt_pass *all_passes, *all_ipa_passes, *all_lowering_passes;
 302
 303 /* Iterate over the pass tree allocating dump file numbers.  We want
 304    to do this depth first, and independent of whether the pass is
 305    enabled or not.  */
 306
 307 static void
 308 register_one_dump_file (struct tree_opt_pass *pass, bool ipa, int n)
 309 {
 310   char *dot_name, *flag_name, *glob_name;
 311   char num[10];
 312
 313   /* See below in next_pass_1.  */
 314   num[0] = '\0';
 315   if (pass->static_pass_number != -1)
 316     sprintf (num, "%d", ((int) pass->static_pass_number < 0
 317                          ? 1 : pass->static_pass_number));
 318
 319   dot_name = concat (".", pass->name, num, NULL);
 320   if (ipa)
 321     {
 322       flag_name = concat ("ipa-", pass->name, num, NULL);
 323       glob_name = concat ("ipa-", pass->name, NULL);
 324       /* First IPA dump is cgraph that is dumped via separate channels.  */
 325       pass->static_pass_number = dump_register (dot_name, flag_name, glob_name,
 326                                                 TDF_IPA, n + 1, 0);
 327     }
 328   else if (pass->properties_provided & PROP_trees)
 329     {
 330       flag_name = concat ("tree-", pass->name, num, NULL);
 331       glob_name = concat ("tree-", pass->name, NULL);
 332       pass->static_pass_number = dump_register (dot_name, flag_name, glob_name,
 333                                                 TDF_TREE, n + TDI_tree_all, 0);
 334     }
 335   else
 336     {
 337       flag_name = concat ("rtl-", pass->name, num, NULL);
 338       glob_name = concat ("rtl-", pass->name, NULL);
 339       pass->static_pass_number = dump_register (dot_name, flag_name, glob_name,
 340                                                 TDF_RTL, n, pass->letter);
 341     }
 342 }
 343
 344 static int
 345 register_dump_files (struct tree_opt_pass *pass, bool ipa, int properties)
 346 {
 347   static int n = 0;
 348   do
 349     {
 350       int new_properties;
 351       int pass_number;
 352
 353       pass->properties_required = properties;
 354       new_properties =
 355         (properties | pass->properties_provided) & ~pass->properties_destroyed;
 356
 357       /* Reset the counter when we reach RTL-based passes.  */
 358       if ((new_properties ^ pass->properties_required) & PROP_rtl)
 359         n = 0;
 360
 361       pass_number = n;
 362       if (pass->name)
 363         n++;
 364
 365       if (pass->sub)
 366         new_properties = register_dump_files (pass->sub, false, new_properties);
 367
 368       /* If we have a gate, combine the properties that we could have with
 369          and without the pass being examined.  */
 370       if (pass->gate)
 371         properties &= new_properties;
 372       else
 373         properties = new_properties;
 374
 375       pass->properties_provided = properties;
 376       if (pass->name)
 377         register_one_dump_file (pass, ipa, pass_number);
 378
 379       pass = pass->next;
 380     }
 381   while (pass);
 382
 383   return properties;
 384 }
 385
 386 /* Add a pass to the pass list. Duplicate the pass if it's already
 387    in the list.  */
 388
 389 static struct tree_opt_pass **
 390 next_pass_1 (struct tree_opt_pass **list, struct tree_opt_pass *pass)
 391 {
 392
 393   /* A nonzero static_pass_number indicates that the
 394      pass is already in the list.  */
 395   if (pass->static_pass_number)
 396     {
 397       struct tree_opt_pass *new;
 398
 399       new = xmalloc (sizeof (*new));
 400       memcpy (new, pass, sizeof (*new));
 401
 402       /* Indicate to register_dump_files that this pass has duplicates,
 403          and so it should rename the dump file.  The first instance will
 404          be -1, and be number of duplicates = -static_pass_number - 1.
 405          Subsequent instances will be > 0 and just the duplicate number.  */
 406       if (pass->name)
 407         {
 408           pass->static_pass_number -= 1;
 409           new->static_pass_number = -pass->static_pass_number;
 410         }
 411
 412       *list = new;
 413     }
 414   else
 415     {
 416       pass->static_pass_number = -1;
 417       *list = pass;
 418     }
 419
 420   return &(*list)->next;
 421
 422 }
 423
 424 /* Construct the pass tree.  */
 425
 426 void
 427 init_optimization_passes (void)
 428 {
 429   struct tree_opt_pass **p;
 430
 431 #define NEXT_PASS(PASS)  (p = next_pass_1 (p, &PASS))
 432   /* Interprocedural optimization passes.  */
 433   p = &all_ipa_passes;
 434   NEXT_PASS (pass_early_ipa_inline);
 435   NEXT_PASS (pass_early_local_passes);
 436   NEXT_PASS (pass_ipa_cp);
 437   NEXT_PASS (pass_ipa_inline);
 438   NEXT_PASS (pass_ipa_reference);
 439   NEXT_PASS (pass_ipa_pure_const);
 440   NEXT_PASS (pass_ipa_type_escape);
 441   *p = NULL;
 442
 443   /* All passes needed to lower the function into shape optimizers can operate
 444      on.  These passes are performed before interprocedural passes, unlike rest
 445      of local passes (all_passes).  */
 446   p = &all_lowering_passes;
 447   NEXT_PASS (pass_remove_useless_stmts);
 448   NEXT_PASS (pass_mudflap_1);
 449   NEXT_PASS (pass_lower_cf);
 450   NEXT_PASS (pass_lower_eh);
 451   NEXT_PASS (pass_build_cfg);
 452   NEXT_PASS (pass_lower_complex_O0);
 453   NEXT_PASS (pass_lower_vector);
 454   NEXT_PASS (pass_warn_function_return);
 455   NEXT_PASS (pass_early_tree_profile);
 456   *p = NULL;
 457
 458   p = &pass_early_local_passes.sub;
 459   NEXT_PASS (pass_tree_profile);
 460   NEXT_PASS (pass_cleanup_cfg);
 461   NEXT_PASS (pass_rebuild_cgraph_edges);
 462   *p = NULL;
 463
 464   p = &all_passes;
 465   NEXT_PASS (pass_fixup_cfg);
 466   NEXT_PASS (pass_init_datastructures);
 467   NEXT_PASS (pass_all_optimizations);
 468   NEXT_PASS (pass_warn_function_noreturn);
 469   NEXT_PASS (pass_mudflap_2);
 470   NEXT_PASS (pass_free_datastructures);
 471   NEXT_PASS (pass_free_cfg_annotations);
 472   NEXT_PASS (pass_expand);
 473   NEXT_PASS (pass_rest_of_compilation);
 474   NEXT_PASS (pass_clean_state);
 475   *p = NULL;
 476
 477   p = &pass_all_optimizations.sub;
 478   NEXT_PASS (pass_referenced_vars);
 479   NEXT_PASS (pass_create_structure_vars);
 480   NEXT_PASS (pass_build_ssa);
 481   NEXT_PASS (pass_may_alias);
 482   NEXT_PASS (pass_return_slot);
 483   NEXT_PASS (pass_rename_ssa_copies);
 484   NEXT_PASS (pass_early_warn_uninitialized);
 485   NEXT_PASS (pass_eliminate_useless_stores);
 486
 487   /* Initial scalar cleanups.  */
 488   NEXT_PASS (pass_ccp);
 489   NEXT_PASS (pass_fre);
 490   NEXT_PASS (pass_dce);
 491   NEXT_PASS (pass_forwprop);
 492   NEXT_PASS (pass_copy_prop);
 493   NEXT_PASS (pass_vrp);
 494   NEXT_PASS (pass_dce);
 495   NEXT_PASS (pass_merge_phi);
 496   NEXT_PASS (pass_dominator);
 497
 498   NEXT_PASS (pass_phiopt);
 499   NEXT_PASS (pass_may_alias);
 500   NEXT_PASS (pass_tail_recursion);
 501   NEXT_PASS (pass_profile);
 502   NEXT_PASS (pass_ch);
 503   NEXT_PASS (pass_stdarg);
 504   NEXT_PASS (pass_lower_complex);
 505   NEXT_PASS (pass_sra);
 506   /* FIXME: SRA may generate arbitrary gimple code, exposing new
 507      aliased and call-clobbered variables.  As mentioned below,
 508      pass_may_alias should be a TODO item.  */
 509   NEXT_PASS (pass_may_alias);
 510   NEXT_PASS (pass_rename_ssa_copies);
 511   NEXT_PASS (pass_dominator);
 512   NEXT_PASS (pass_copy_prop);
 513   NEXT_PASS (pass_dce);
 514   NEXT_PASS (pass_dse);
 515   NEXT_PASS (pass_may_alias);
 516   NEXT_PASS (pass_forwprop);
 517   NEXT_PASS (pass_phiopt);
 518   NEXT_PASS (pass_object_sizes);
 519   NEXT_PASS (pass_store_ccp);
 520   NEXT_PASS (pass_store_copy_prop);
 521   NEXT_PASS (pass_fold_builtins);
 522   /* FIXME: May alias should a TODO but for 4.0.0,
 523      we add may_alias right after fold builtins
 524      which can create arbitrary GIMPLE.  */
 525   NEXT_PASS (pass_may_alias);
 526   NEXT_PASS (pass_cse_reciprocals);
 527   NEXT_PASS (pass_split_crit_edges);
 528   NEXT_PASS (pass_reassoc);
 529   NEXT_PASS (pass_pre);
 530   NEXT_PASS (pass_sink_code);
 531   NEXT_PASS (pass_tree_loop);
 532   NEXT_PASS (pass_dominator);
 533   NEXT_PASS (pass_copy_prop);
 534   NEXT_PASS (pass_cd_dce);
 535
 536   /* FIXME: If DCE is not run before checking for uninitialized uses,
 537      we may get false warnings (e.g., testsuite/gcc.dg/uninit-5.c).
 538      However, this also causes us to misdiagnose cases that should be
 539      real warnings (e.g., testsuite/gcc.dg/pr18501.c).
 540
 541      To fix the false positives in uninit-5.c, we would have to
 542      account for the predicates protecting the set and the use of each
 543      variable.  Using a representation like Gated Single Assignment
 544      may help.  */
 545   NEXT_PASS (pass_late_warn_uninitialized);
 546   NEXT_PASS (pass_dse);
 547   NEXT_PASS (pass_forwprop);
 548   NEXT_PASS (pass_phiopt);
 549   NEXT_PASS (pass_tail_calls);
 550   NEXT_PASS (pass_rename_ssa_copies);
 551   NEXT_PASS (pass_uncprop);
 552   NEXT_PASS (pass_del_ssa);
 553   NEXT_PASS (pass_nrv);
 554   NEXT_PASS (pass_remove_useless_vars);
 555   NEXT_PASS (pass_mark_used_blocks);
 556   NEXT_PASS (pass_cleanup_cfg_post_optimizing);
 557   *p = NULL;
 558
 559   p = &pass_tree_loop.sub;
 560   NEXT_PASS (pass_tree_loop_init);
 561   NEXT_PASS (pass_copy_prop);
 562   NEXT_PASS (pass_lim);
 563   NEXT_PASS (pass_tree_unswitch);
 564   NEXT_PASS (pass_scev_cprop);
 565   NEXT_PASS (pass_empty_loop);
 566   NEXT_PASS (pass_record_bounds);
 567   NEXT_PASS (pass_linear_transform);
 568   NEXT_PASS (pass_iv_canon);
 569   NEXT_PASS (pass_if_conversion);
 570   NEXT_PASS (pass_vectorize);
 571   /* NEXT_PASS (pass_may_alias) cannot be done again because the
 572      vectorizer creates alias relations that are not supported by
 573      pass_may_alias.  */
 574   NEXT_PASS (pass_lower_vector_ssa);
 575   NEXT_PASS (pass_complete_unroll);
 576   NEXT_PASS (pass_iv_optimize);
 577   NEXT_PASS (pass_tree_loop_done);
 578   *p = NULL;
 579
 580   p = &pass_loop2.sub;
 581   NEXT_PASS (pass_rtl_loop_init);
 582   NEXT_PASS (pass_rtl_move_loop_invariants);
 583   NEXT_PASS (pass_rtl_unswitch);
 584   NEXT_PASS (pass_rtl_unroll_and_peel_loops);
 585   NEXT_PASS (pass_rtl_doloop);
 586   NEXT_PASS (pass_rtl_loop_done);
 587   *p = NULL;
 588
 589   p = &pass_rest_of_compilation.sub;
 590   NEXT_PASS (pass_remove_unnecessary_notes);
 591   NEXT_PASS (pass_init_function);
 592   NEXT_PASS (pass_jump);
 593   NEXT_PASS (pass_insn_locators_initialize);
 594   NEXT_PASS (pass_rtl_eh);
 595   NEXT_PASS (pass_initial_value_sets);
 596   NEXT_PASS (pass_unshare_all_rtl);
 597   NEXT_PASS (pass_instantiate_virtual_regs);
 598   NEXT_PASS (pass_jump2);
 599   NEXT_PASS (pass_cse);
 600   NEXT_PASS (pass_gcse);
 601   NEXT_PASS (pass_loop_optimize);
 602   NEXT_PASS (pass_jump_bypass);
 603   NEXT_PASS (pass_cfg);
 604   NEXT_PASS (pass_branch_prob);
 605   NEXT_PASS (pass_rtl_ifcvt);
 606   NEXT_PASS (pass_tracer);
 607   /* Perform loop optimizations.  It might be better to do them a bit
 608      sooner, but we want the profile feedback to work more
 609      efficiently.  */
 610   NEXT_PASS (pass_loop2);
 611   NEXT_PASS (pass_web);
 612   NEXT_PASS (pass_cse2);
 613   NEXT_PASS (pass_life);
 614   NEXT_PASS (pass_combine);
 615   NEXT_PASS (pass_if_after_combine);
 616   NEXT_PASS (pass_partition_blocks);
 617   NEXT_PASS (pass_regmove);
 618   NEXT_PASS (pass_split_all_insns);
 619   NEXT_PASS (pass_mode_switching);
 620   NEXT_PASS (pass_recompute_reg_usage);
 621   NEXT_PASS (pass_sms);
 622   NEXT_PASS (pass_sched);
 623   NEXT_PASS (pass_local_alloc);
 624   NEXT_PASS (pass_global_alloc);
 625   NEXT_PASS (pass_postreload);
 626   *p = NULL;
 627
 628   p = &pass_postreload.sub;
 629   NEXT_PASS (pass_postreload_cse);
 630   NEXT_PASS (pass_gcse2);
 631   NEXT_PASS (pass_flow2);
 632   NEXT_PASS (pass_stack_adjustments);
 633   NEXT_PASS (pass_peephole2);
 634   NEXT_PASS (pass_if_after_reload);
 635   NEXT_PASS (pass_regrename);
 636   NEXT_PASS (pass_reorder_blocks);
 637   NEXT_PASS (pass_branch_target_load_optimize);
 638   NEXT_PASS (pass_leaf_regs);
 639   NEXT_PASS (pass_sched2);
 640   NEXT_PASS (pass_split_before_regstack);
 641   NEXT_PASS (pass_stack_regs);
 642   NEXT_PASS (pass_compute_alignments);
 643   NEXT_PASS (pass_duplicate_computed_gotos);
 644   NEXT_PASS (pass_variable_tracking);
 645   NEXT_PASS (pass_free_cfg);
 646   NEXT_PASS (pass_machine_reorg);
 647   NEXT_PASS (pass_purge_lineno_notes);
 648   NEXT_PASS (pass_cleanup_barriers);
 649   NEXT_PASS (pass_delay_slots);
 650   NEXT_PASS (pass_split_for_shorten_branches);
 651   NEXT_PASS (pass_convert_to_eh_region_ranges);
 652   NEXT_PASS (pass_shorten_branches);
 653   NEXT_PASS (pass_set_nothrow_function_flags);
 654   NEXT_PASS (pass_final);
 655   *p = NULL;
 656
 657 #undef NEXT_PASS
 658
 659   /* Register the passes with the tree dump code.  */
 660   register_dump_files (all_lowering_passes, false, PROP_gimple_any);
 661   register_dump_files (all_passes, false, PROP_gimple_leh
 662                                           | PROP_cfg);
 663   register_dump_files (all_ipa_passes, true, PROP_gimple_leh
 664                                              | PROP_cfg);
 665 }
 666
 667 static unsigned int last_verified;
 668
 669 static void
 670 execute_todo (struct tree_opt_pass *pass, unsigned int flags, bool use_required)
 671 {
 672   int properties
 673     = use_required ? pass->properties_required : pass->properties_provided;
 674
 675 #if defined ENABLE_CHECKING
 676   if (need_ssa_update_p ())
 677     gcc_assert (flags & TODO_update_ssa_any);
 678 #endif
 679
 680   /* Always cleanup the CFG before doing anything else.  */
 681   if (flags & TODO_cleanup_cfg)
 682     {
 683       if (current_loops)
 684         cleanup_tree_cfg_loop ();
 685       else
 686         cleanup_tree_cfg ();
 687
 688       /* When cleanup_tree_cfg merges consecutive blocks, it may
 689          perform some simplistic propagation when removing single
 690          valued PHI nodes.  This propagation may, in turn, cause the
 691          SSA form to become out-of-date (see PR 22037).  So, even
 692          if the parent pass had not scheduled an SSA update, we may
 693          still need to do one.  */
 694       if (!(flags & TODO_update_ssa_any) && need_ssa_update_p ())
 695         flags |= TODO_update_ssa;
 696     }
 697
 698   if (flags & TODO_update_ssa_any)
 699     {
 700       unsigned update_flags = flags & TODO_update_ssa_any;
 701       update_ssa (update_flags);
 702     }
 703
 704   if ((flags & TODO_dump_func)
 705       && dump_file && current_function_decl)
 706     {
 707       if (properties & PROP_trees)
 708         dump_function_to_file (current_function_decl,
 709                                dump_file, dump_flags);
 710       else if (properties & PROP_cfg)
 711         print_rtl_with_bb (dump_file, get_insns ());
 712       else
 713         print_rtl (dump_file, get_insns ());
 714
 715       /* Flush the file.  If verification fails, we won't be able to
 716          close the file before aborting.  */
 717       fflush (dump_file);
 718     }
 719   if ((flags & TODO_dump_cgraph)
 720       && dump_file && !current_function_decl)
 721     {
 722       dump_cgraph (dump_file);
 723       /* Flush the file.  If verification fails, we won't be able to
 724          close the file before aborting.  */
 725       fflush (dump_file);
 726     }
 727
 728   if (flags & TODO_ggc_collect)
 729     {
 730       ggc_collect ();
 731     }
 732
 733 #if defined ENABLE_CHECKING
 734   if ((pass->properties_required & PROP_ssa)
 735       && !(pass->properties_destroyed & PROP_ssa))
 736     verify_ssa (true);
 737   if (flags & TODO_verify_flow)
 738     verify_flow_info ();
 739   if (flags & TODO_verify_stmts)
 740     verify_stmts ();
 741   if (flags & TODO_verify_loops)
 742     verify_loop_closed_ssa ();
 743 #endif
 744 }
 745
 746 static bool
 747 execute_one_pass (struct tree_opt_pass *pass)
 748 {
 749   unsigned int todo;
 750
 751   /* See if we're supposed to run this pass.  */
 752   if (pass->gate && !pass->gate ())
 753     return false;
 754
 755   /* Note that the folders should only create gimple expressions.
 756      This is a hack until the new folder is ready.  */
 757   in_gimple_form = (pass->properties_provided & PROP_trees) != 0;
 758
 759   /* Run pre-pass verification.  */
 760   todo = pass->todo_flags_start & ~last_verified;
 761   if (todo)
 762     execute_todo (pass, todo, true);
 763
 764   /* If a dump file name is present, open it if enabled.  */
 765   if (pass->static_pass_number != -1)
 766     {
 767       bool initializing_dump = !dump_initialized_p (pass->static_pass_number);
 768       dump_file_name = get_dump_file_name (pass->static_pass_number);
 769       dump_file = dump_begin (pass->static_pass_number, &dump_flags);
 770       if (dump_file && current_function_decl)
 771         {
 772           const char *dname, *aname;
 773           dname = lang_hooks.decl_printable_name (current_function_decl, 2);
 774           aname = (IDENTIFIER_POINTER
 775                    (DECL_ASSEMBLER_NAME (current_function_decl)));
 776           fprintf (dump_file, "\n;; Function %s (%s)%s\n\n", dname, aname,
 777              cfun->function_frequency == FUNCTION_FREQUENCY_HOT
 778              ? " (hot)"
 779              : cfun->function_frequency == FUNCTION_FREQUENCY_UNLIKELY_EXECUTED
 780              ? " (unlikely executed)"
 781              : "");
 782         }
 783
 784       if (initializing_dump
 785           && graph_dump_format != no_graph
 786           && (pass->properties_provided & (PROP_cfg | PROP_rtl))
 787               == (PROP_cfg | PROP_rtl))
 788         clean_graph_dump_file (dump_file_name);
 789     }
 790
 791   /* If a timevar is present, start it.  */
 792   if (pass->tv_id)
 793     timevar_push (pass->tv_id);
 794
 795   /* Do it!  */
 796   if (pass->execute)
 797     pass->execute ();
 798
 799   /* Stop timevar.  */
 800   if (pass->tv_id)
 801     timevar_pop (pass->tv_id);
 802
 803   /* Run post-pass cleanup and verification.  */
 804   todo = pass->todo_flags_finish;
 805   last_verified = todo & TODO_verify_all;
 806   if (todo)
 807     execute_todo (pass, todo, false);
 808
 809   /* Flush and close dump file.  */
 810   if (dump_file_name)
 811     {
 812       free ((char *) dump_file_name);
 813       dump_file_name = NULL;
 814     }
 815   if (dump_file)
 816     {
 817       dump_end (pass->static_pass_number, dump_file);
 818       dump_file = NULL;
 819     }
 820
 821   return true;
 822 }
 823
 824 void
 825 execute_pass_list (struct tree_opt_pass *pass)
 826 {
 827   do
 828     {
 829       if (execute_one_pass (pass) && pass->sub)
 830         execute_pass_list (pass->sub);
 831       pass = pass->next;
 832     }
 833   while (pass);
 834 }
 835
 836 /* Same as execute_pass_list but assume that subpasses of IPA passes
 837    are local passes.  */
 838 void
 839 execute_ipa_pass_list (struct tree_opt_pass *pass)
 840 {
 841   do
 842     {
 843       if (execute_one_pass (pass) && pass->sub)
 844         {
 845           struct cgraph_node *node;
 846           for (node = cgraph_nodes; node; node = node->next)
 847             if (node->analyzed)
 848               {
 849                 push_cfun (DECL_STRUCT_FUNCTION (node->decl));
 850                 current_function_decl = node->decl;
 851                 execute_pass_list (pass->sub);
 852                 free_dominance_info (CDI_DOMINATORS);
 853                 free_dominance_info (CDI_POST_DOMINATORS);
 854                 current_function_decl = NULL;
 855                 pop_cfun ();
 856                 ggc_collect ();
 857               }
 858         }
 859       pass = pass->next;
 860     }
 861   while (pass);
 862 }