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gcc/
[pf3gnuchains/gcc-fork.git] / gcc / tree-optimize.c
index fed16c3..544d75d 100644 (file)
@@ -1,12 +1,12 @@
 /* Top-level control of tree optimizations.
-   Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+   Copyright 2001, 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
    Contributed by Diego Novillo <dnovillo@redhat.com>
 
 This file is part of GCC.
 
 GCC is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
 any later version.
 
 GCC is distributed in the hope that it will be useful,
@@ -15,9 +15,8 @@ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING.  If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.  */
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
 
 #include "config.h"
 #include "system.h"
@@ -47,50 +46,87 @@ Boston, MA 02111-1307, USA.  */
 #include "ggc.h"
 #include "cgraph.h"
 #include "graph.h"
+#include "cfgloop.h"
+#include "except.h"
 
 
-/* Global variables used to communicate with passes.  */
-int dump_flags;
-bitmap vars_to_rename;
-bool in_gimple_form;
+/* Gate: execute, or not, all of the non-trivial optimizations.  */
 
-/* The root of the compilation pass tree, once constructed.  */
-static struct tree_opt_pass *all_passes;
+static bool
+gate_all_optimizations (void)
+{
+  return (optimize >= 1
+         /* Don't bother doing anything if the program has errors. 
+            We have to pass down the queue if we already went into SSA */
+         && (!(errorcount || sorrycount) || gimple_in_ssa_p (cfun)));
+}
 
-/* Pass: dump the gimplified, inlined, functions.  */
+struct tree_opt_pass pass_all_optimizations =
+{
+  NULL,                                        /* name */
+  gate_all_optimizations,              /* gate */
+  NULL,                                        /* execute */
+  NULL,                                        /* sub */
+  NULL,                                        /* next */
+  0,                                   /* static_pass_number */
+  0,                                   /* tv_id */
+  0,                                   /* properties_required */
+  0,                                   /* properties_provided */
+  0,                                   /* properties_destroyed */
+  0,                                   /* todo_flags_start */
+  0,                                   /* todo_flags_finish */
+  0                                    /* letter */
+};
+
+/* Gate: execute, or not, all of the non-trivial optimizations.  */
 
-static struct tree_opt_pass pass_gimple = 
+static bool
+gate_all_early_local_passes (void)
 {
-  "gimple",                            /* name */
-  NULL,                                        /* gate */
+         /* Don't bother doing anything if the program has errors.  */
+  return (!errorcount && !sorrycount);
+}
+
+struct tree_opt_pass pass_early_local_passes =
+{
+  "early_local_cleanups",              /* name */
+  gate_all_early_local_passes,         /* gate */
   NULL,                                        /* execute */
   NULL,                                        /* sub */
   NULL,                                        /* next */
   0,                                   /* static_pass_number */
   0,                                   /* tv_id */
   0,                                   /* properties_required */
-  PROP_gimple_any,                     /* properties_provided */
+  0,                                   /* properties_provided */
   0,                                   /* properties_destroyed */
   0,                                   /* todo_flags_start */
-  TODO_dump_func,                      /* todo_flags_finish */
+  TODO_remove_functions,               /* todo_flags_finish */
   0                                    /* letter */
 };
 
+static unsigned int
+execute_early_local_optimizations (void)
+{
+  if (flag_unit_at_a_time)
+    cgraph_state = CGRAPH_STATE_IPA_SSA;
+  return 0;
+}
+
 /* Gate: execute, or not, all of the non-trivial optimizations.  */
 
 static bool
-gate_all_optimizations (void)
+gate_all_early_optimizations (void)
 {
   return (optimize >= 1
          /* Don't bother doing anything if the program has errors.  */
          && !(errorcount || sorrycount));
 }
 
-static struct tree_opt_pass pass_all_optimizations =
+struct tree_opt_pass pass_all_early_optimizations =
 {
-  NULL,                                        /* name */
-  gate_all_optimizations,              /* gate */
-  NULL,                                        /* execute */
+  "early_optimizations",               /* name */
+  gate_all_early_optimizations,                /* gate */
+  execute_early_local_optimizations,   /* execute */
   NULL,                                        /* sub */
   NULL,                                        /* next */
   0,                                   /* static_pass_number */
@@ -108,17 +144,49 @@ static struct tree_opt_pass pass_all_optimizations =
    because after the tree optimizers have run such cleanups may
    be necessary.  */
 
-static void 
+static unsigned int
+execute_cleanup_cfg_pre_ipa (void)
+{
+  cleanup_tree_cfg ();
+  return 0;
+}
+
+struct tree_opt_pass pass_cleanup_cfg =
+{
+  "cleanup_cfg",                       /* name */
+  NULL,                                        /* gate */
+  execute_cleanup_cfg_pre_ipa,         /* execute */
+  NULL,                                        /* sub */
+  NULL,                                        /* next */
+  0,                                   /* static_pass_number */
+  0,                                   /* tv_id */
+  PROP_cfg,                            /* properties_required */
+  0,                                   /* properties_provided */
+  0,                                   /* properties_destroyed */
+  0,                                   /* todo_flags_start */
+  TODO_dump_func,                                      /* todo_flags_finish */
+  0                                    /* letter */
+};
+
+
+/* Pass: cleanup the CFG just before expanding trees to RTL.
+   This is just a round of label cleanups and case node grouping
+   because after the tree optimizers have run such cleanups may
+   be necessary.  */
+
+static unsigned int
 execute_cleanup_cfg_post_optimizing (void)
 {
+  fold_cond_expr_cond ();
   cleanup_tree_cfg ();
   cleanup_dead_labels ();
   group_case_labels ();
+  return 0;
 }
 
-static struct tree_opt_pass pass_cleanup_cfg_post_optimizing =
+struct tree_opt_pass pass_cleanup_cfg_post_optimizing =
 {
-  NULL,                                        /* name */
+  "final_cleanup",                     /* name */
   NULL,                                        /* gate */
   execute_cleanup_cfg_post_optimizing, /* execute */
   NULL,                                        /* sub */
@@ -129,38 +197,26 @@ static struct tree_opt_pass pass_cleanup_cfg_post_optimizing =
   0,                                   /* properties_provided */
   0,                                   /* properties_destroyed */
   0,                                   /* todo_flags_start */
-  0,                                   /* todo_flags_finish */
+  TODO_dump_func,                                      /* todo_flags_finish */
   0                                    /* letter */
 };
 
 /* Pass: do the actions required to finish with tree-ssa optimization
    passes.  */
 
-static void
+static unsigned int
 execute_free_datastructures (void)
 {
-  tree *chain;
-
-  /* ??? This isn't the right place for this.  Worse, it got computed
-     more or less at random in various passes.  */
   free_dominance_info (CDI_DOMINATORS);
+  free_dominance_info (CDI_POST_DOMINATORS);
 
-  /* Emit gotos for implicit jumps.  */
-  disband_implicit_edges ();
-
-  /* Remove the ssa structures.  Do it here since this includes statement
-     annotations that need to be intact during disband_implicit_edges.  */
-  delete_tree_ssa ();
-
-  /* Re-chain the statements from the blocks.  */
-  chain = &DECL_SAVED_TREE (current_function_decl);
-  *chain = alloc_stmt_list ();
-
-  /* And get rid of annotations we no longer need.  */
-  delete_tree_cfg_annotations ();
+  /* Remove the ssa structures.  */
+  if (cfun->gimple_df)
+    delete_tree_ssa ();
+  return 0;
 }
 
-static struct tree_opt_pass pass_free_datastructures =
+struct tree_opt_pass pass_free_datastructures =
 {
   NULL,                                        /* name */
   NULL,                                        /* gate */
@@ -176,23 +232,22 @@ static struct tree_opt_pass pass_free_datastructures =
   0,                                   /* todo_flags_finish */
   0                                    /* letter */
 };
+/* Pass: free cfg annotations.  */
 
-
-/* Do the actions required to initialize internal data structures used
-   in tree-ssa optimization passes.  */
-
-static void
-execute_init_datastructures (void)
+static unsigned int
+execute_free_cfg_annotations (void)
 {
-  /* Allocate hash tables, arrays and other structures.  */
-  init_tree_ssa ();
+  /* And get rid of annotations we no longer need.  */
+  delete_tree_cfg_annotations ();
+
+  return 0;
 }
 
-static struct tree_opt_pass pass_init_datastructures =
+struct tree_opt_pass pass_free_cfg_annotations =
 {
   NULL,                                        /* name */
   NULL,                                        /* gate */
-  execute_init_datastructures,         /* execute */
+  execute_free_cfg_annotations,                /* execute */
   NULL,                                        /* sub */
   NULL,                                        /* next */
   0,                                   /* static_pass_number */
@@ -205,363 +260,112 @@ static struct tree_opt_pass pass_init_datastructures =
   0                                    /* letter */
 };
 
-/* Iterate over the pass tree allocating dump file numbers.  We want
-   to do this depth first, and independent of whether the pass is
-   enabled or not.  */
+/* Pass: fixup_cfg.  IPA passes, compilation of earlier functions or inlining
+   might have changed some properties, such as marked functions nothrow.
+   Remove redundant edges and basic blocks, and create new ones if necessary.
 
-static void
-register_one_dump_file (struct tree_opt_pass *pass, int n)
-{
-  char *dot_name, *flag_name;
-  char num[10];
-
-  /* See below in next_pass_1.  */
-  num[0] = '\0';
-  if (pass->static_pass_number != -1)
-    sprintf (num, "%d", ((int) pass->static_pass_number < 0
-                        ? 1 : pass->static_pass_number));
-
-  dot_name = concat (".", pass->name, num, NULL);
-  if (pass->properties_provided & PROP_trees)
-    {
-      flag_name = concat ("tree-", pass->name, num, NULL);
-      pass->static_pass_number = dump_register (dot_name, flag_name,
-                                                TDF_TREE, n + TDI_tree_all, 0);
-    }
-  else
-    {
-      flag_name = concat ("rtl-", pass->name, num, NULL);
-      pass->static_pass_number = dump_register (dot_name, flag_name,
-                                                TDF_RTL, n, pass->letter);
-    }
-}
+   This pass can't be executed as stand alone pass from pass manager, because
+   in between inlining and this fixup the verify_flow_info would fail.  */
 
-static int 
-register_dump_files (struct tree_opt_pass *pass, int properties)
-{
-  static int n = 0;
-  do
-    {
-      int new_properties;
-      int pass_number;
-
-      pass->properties_required = properties;
-      new_properties =
-        (properties | pass->properties_provided) & ~pass->properties_destroyed;
-
-      /* Reset the counter when we reach RTL-based passes.  */
-      if ((pass->properties_provided ^ pass->properties_required) & PROP_rtl)
-        n = 0;
-
-      pass_number = n;
-      if (pass->name)
-        n++;
-
-      if (pass->sub)
-        new_properties = register_dump_files (pass->sub, new_properties);
-
-      /* If we have a gate, combine the properties that we could have with
-         and without the pass being examined.  */
-      if (pass->gate)
-        properties &= new_properties;
-      else
-        properties = new_properties;
-
-      pass->properties_provided = properties;
-      if (pass->name)
-        register_one_dump_file (pass, pass_number);
-
-      pass = pass->next;
-    }
-  while (pass);
-
-  return properties;
-}
-
-/* Add a pass to the pass list. Duplicate the pass if it's already
-   in the list.  */
-
-static struct tree_opt_pass **
-next_pass_1 (struct tree_opt_pass **list, struct tree_opt_pass *pass)
+unsigned int
+execute_fixup_cfg (void)
 {
+  basic_block bb;
+  block_stmt_iterator bsi;
+  int todo = gimple_in_ssa_p (cfun) ? TODO_verify_ssa : 0;
+
+  cfun->after_inlining = true;
+
+  if (cfun->eh)
+    FOR_EACH_BB (bb)
+      {
+       for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+         {
+           tree stmt = bsi_stmt (bsi);
+           tree call = get_call_expr_in (stmt);
+           tree decl = call ? get_callee_fndecl (call) : NULL;
+
+           if (decl && call_expr_flags (call) & (ECF_CONST | ECF_PURE)
+               && TREE_SIDE_EFFECTS (call))
+             {
+               if (gimple_in_ssa_p (cfun))
+                 {
+                   todo |= TODO_update_ssa | TODO_cleanup_cfg;
+                   update_stmt (stmt);
+                 }
+               TREE_SIDE_EFFECTS (call) = 0;
+             }
+           if (decl && TREE_NOTHROW (decl))
+             TREE_NOTHROW (call) = 1;
+           if (!tree_could_throw_p (stmt) && lookup_stmt_eh_region (stmt))
+             remove_stmt_from_eh_region (stmt);
+         }
+       if (tree_purge_dead_eh_edges (bb))
+          todo |= TODO_cleanup_cfg;
+      }
+
+  /* Dump a textual representation of the flowgraph.  */
+  if (dump_file)
+    dump_tree_cfg (dump_file, dump_flags);
 
-  /* A nonzero static_pass_number indicates that the
-     pass is already in the list.  */
-  if (pass->static_pass_number)
-    {
-      struct tree_opt_pass *new;
-
-      new = xmalloc (sizeof (*new));
-      memcpy (new, pass, sizeof (*new));
-
-      /* Indicate to register_dump_files that this pass has duplicates,
-         and so it should rename the dump file.  The first instance will
-         be -1, and be number of duplicates = -static_pass_number - 1.
-         Subsequent instances will be > 0 and just the duplicate number.  */
-      if (pass->name)
-        {
-          pass->static_pass_number -= 1;
-          new->static_pass_number = -pass->static_pass_number;
-       }
-      
-      *list = new;
-    }
-  else
-    {
-      pass->static_pass_number = -1;
-      *list = pass;
-    }  
-  
-  return &(*list)->next;
-          
+  return todo;
 }
 
-/* Construct the pass tree.  */
+/* Do the actions required to initialize internal data structures used
+   in tree-ssa optimization passes.  */
 
-void
-init_tree_optimization_passes (void)
+static unsigned int
+execute_init_datastructures (void)
 {
-  struct tree_opt_pass **p;
-
-#define NEXT_PASS(PASS)  (p = next_pass_1 (p, &PASS))
-
-  p = &all_passes;
-  NEXT_PASS (pass_gimple);
-  NEXT_PASS (pass_remove_useless_stmts);
-  NEXT_PASS (pass_mudflap_1);
-  NEXT_PASS (pass_lower_cf);
-  NEXT_PASS (pass_lower_eh);
-  NEXT_PASS (pass_build_cfg);
-  NEXT_PASS (pass_pre_expand);
-  NEXT_PASS (pass_tree_profile);
-  NEXT_PASS (pass_init_datastructures);
-  NEXT_PASS (pass_all_optimizations);
-  NEXT_PASS (pass_warn_function_return);
-  NEXT_PASS (pass_mudflap_2);
-  NEXT_PASS (pass_free_datastructures);
-  NEXT_PASS (pass_expand);
-  NEXT_PASS (pass_rest_of_compilation);
-  *p = NULL;
-
-  p = &pass_all_optimizations.sub;
-  NEXT_PASS (pass_referenced_vars);
-  NEXT_PASS (pass_build_ssa);
-  NEXT_PASS (pass_may_alias);
-  NEXT_PASS (pass_rename_ssa_copies);
-  NEXT_PASS (pass_early_warn_uninitialized);
-  NEXT_PASS (pass_dce);
-  NEXT_PASS (pass_dominator);
-  NEXT_PASS (pass_redundant_phi);
-  NEXT_PASS (pass_dce);
-  NEXT_PASS (pass_forwprop);
-  NEXT_PASS (pass_phiopt);
-  NEXT_PASS (pass_may_alias);
-  NEXT_PASS (pass_tail_recursion);
-  NEXT_PASS (pass_ch);
-  NEXT_PASS (pass_profile);
-  NEXT_PASS (pass_sra);
-  NEXT_PASS (pass_rename_ssa_copies);
-  NEXT_PASS (pass_dominator);
-  NEXT_PASS (pass_redundant_phi);
-  NEXT_PASS (pass_dce);
-  NEXT_PASS (pass_dse);
-  NEXT_PASS (pass_may_alias);
-  NEXT_PASS (pass_forwprop);
-  NEXT_PASS (pass_phiopt);
-  NEXT_PASS (pass_ccp);
-  NEXT_PASS (pass_redundant_phi);
-  NEXT_PASS (pass_fold_builtins);
-  NEXT_PASS (pass_split_crit_edges);
-  NEXT_PASS (pass_pre);
-  NEXT_PASS (pass_loop);
-  NEXT_PASS (pass_dominator);
-  NEXT_PASS (pass_redundant_phi);
-  NEXT_PASS (pass_cd_dce);
-  NEXT_PASS (pass_dse);
-  NEXT_PASS (pass_forwprop);
-  NEXT_PASS (pass_phiopt);
-  NEXT_PASS (pass_tail_calls);
-  NEXT_PASS (pass_late_warn_uninitialized);
-  NEXT_PASS (pass_del_ssa);
-  NEXT_PASS (pass_nrv);
-  NEXT_PASS (pass_remove_useless_vars);
-  NEXT_PASS (pass_cleanup_cfg_post_optimizing);
-  *p = NULL;
-
-  p = &pass_loop.sub;
-  NEXT_PASS (pass_loop_init);
-  NEXT_PASS (pass_lim);
-  NEXT_PASS (pass_unswitch);
-  NEXT_PASS (pass_iv_canon);
-  NEXT_PASS (pass_record_bounds);
-  NEXT_PASS (pass_if_conversion);
-  NEXT_PASS (pass_vectorize);
-  NEXT_PASS (pass_linear_transform);
-  NEXT_PASS (pass_complete_unroll);
-  NEXT_PASS (pass_iv_optimize);
-  NEXT_PASS (pass_loop_done);
-  *p = NULL;
-
-#undef NEXT_PASS
-
-  /* Register the passes with the tree dump code.  */
-  register_dump_files (all_passes, 0);
+  /* Allocate hash tables, arrays and other structures.  */
+  init_tree_ssa ();
+  return 0;
 }
 
-static void execute_pass_list (struct tree_opt_pass *);
-
-static unsigned int last_verified;
-
-static void
-execute_todo (int properties, unsigned int flags)
-{
-  if (flags & TODO_rename_vars)
-    {
-      rewrite_into_ssa (false);
-      bitmap_clear (vars_to_rename);
-    }
-
-  if ((flags & TODO_dump_func) && dump_file)
-    {
-      if (properties & PROP_trees)
-        dump_function_to_file (current_function_decl,
-                               dump_file, dump_flags);
-      else if (properties & PROP_cfg)
-        print_rtl_with_bb (dump_file, get_insns ());
-      else
-        print_rtl (dump_file, get_insns ());
-
-      /* Flush the file.  If verification fails, we won't be able to
-        close the file before aborting.  */
-      fflush (dump_file);
-    }
-
-  if (flags & TODO_ggc_collect)
-    ggc_collect ();
-
-#ifdef ENABLE_CHECKING
-  if (flags & TODO_verify_ssa)
-    verify_ssa ();
-  if (flags & TODO_verify_flow)
-    verify_flow_info ();
-  if (flags & TODO_verify_stmts)
-    verify_stmts ();
-#endif
-}
+/* Gate: initialize or not the SSA datastructures.  */
 
 static bool
-execute_one_pass (struct tree_opt_pass *pass)
+gate_init_datastructures (void)
 {
-  unsigned int todo; 
-
-  /* See if we're supposed to run this pass.  */
-  if (pass->gate && !pass->gate ())
-    return false;
-
-  /* Note that the folders should only create gimple expressions.
-     This is a hack until the new folder is ready.  */
-  in_gimple_form = (pass->properties_provided & PROP_trees) != 0;
-
-  /* Run pre-pass verification.  */
-  todo = pass->todo_flags_start & ~last_verified;
-  if (todo)
-    execute_todo (pass->properties_required, todo);
-
-  /* If a dump file name is present, open it if enabled.  */
-  if (pass->static_pass_number != -1)
-    {
-      bool initializing_dump = !dump_initialized_p (pass->static_pass_number);
-      dump_file_name = get_dump_file_name (pass->static_pass_number);
-      dump_file = dump_begin (pass->static_pass_number, &dump_flags);
-      if (dump_file)
-       {
-         const char *dname, *aname;
-         dname = lang_hooks.decl_printable_name (current_function_decl, 2);
-         aname = (IDENTIFIER_POINTER
-                  (DECL_ASSEMBLER_NAME (current_function_decl)));
-          fprintf (dump_file, "\n;; Function %s (%s)%s\n\n", dname, aname,
-             cfun->function_frequency == FUNCTION_FREQUENCY_HOT
-             ? " (hot)"
-             : cfun->function_frequency == FUNCTION_FREQUENCY_UNLIKELY_EXECUTED
-             ? " (unlikely executed)"
-             : "");
-       }
-
-      if (initializing_dump
-          && graph_dump_format != no_graph
-         && (pass->properties_provided & (PROP_cfg | PROP_rtl))
-             == (PROP_cfg | PROP_rtl))
-        clean_graph_dump_file (dump_file_name);
-    }
-
-  /* If a timevar is present, start it.  */
-  if (pass->tv_id)
-    timevar_push (pass->tv_id);
-
-  /* Do it!  */
-  if (pass->execute)
-    pass->execute ();
-
-  /* Stop timevar.  */
-  if (pass->tv_id)
-    timevar_pop (pass->tv_id);
-
-  if (dump_file
-      && (pass->properties_provided & (PROP_cfg | PROP_rtl))
-         == (PROP_cfg | PROP_rtl))
-    print_rtl_with_bb (dump_file, get_insns ());
-
-  /* Run post-pass cleanup and verification.  */
-  todo = pass->todo_flags_finish;
-  last_verified = todo & TODO_verify_all;
-  if (todo)
-    execute_todo (pass->properties_provided, todo);
-
-  /* Flush and close dump file.  */
-  if (dump_file_name)
-    {
-      free ((char *) dump_file_name);
-      dump_file_name = NULL;
-    }
-  if (dump_file)
-    {
-      dump_end (pass->static_pass_number, dump_file);
-      dump_file = NULL;
-    }
-
-  return true;
+  return (optimize >= 1);
 }
 
-static void
-execute_pass_list (struct tree_opt_pass *pass)
+struct tree_opt_pass pass_init_datastructures =
 {
-  do
-    {
-      if (execute_one_pass (pass) && pass->sub)
-       execute_pass_list (pass->sub);
-      pass = pass->next;
-    }
-  while (pass);
-}
-\f
+  NULL,                                        /* name */
+  gate_init_datastructures,            /* gate */
+  execute_init_datastructures,         /* execute */
+  NULL,                                        /* sub */
+  NULL,                                        /* next */
+  0,                                   /* static_pass_number */
+  0,                                   /* tv_id */
+  PROP_cfg,                            /* properties_required */
+  0,                                   /* properties_provided */
+  0,                                   /* properties_destroyed */
+  0,                                   /* todo_flags_start */
+  0,                                   /* todo_flags_finish */
+  0                                    /* letter */
+};
 
-/* Update recursively all inlined_to pointers of functions
-   inlined into NODE to INLINED_TO.  */
-static void
-update_inlined_to_pointers (struct cgraph_node *node,
-                           struct cgraph_node *inlined_to)
+void
+tree_lowering_passes (tree fn)
 {
-  struct cgraph_edge *e;
-  for (e = node->callees; e; e = e->next_callee)
-    {
-      if (e->callee->global.inlined_to)
-       {
-         e->callee->global.inlined_to = inlined_to;
-         update_inlined_to_pointers (e->callee, inlined_to);
-       }
-    }
+  tree saved_current_function_decl = current_function_decl;
+
+  current_function_decl = fn;
+  push_cfun (DECL_STRUCT_FUNCTION (fn));
+  tree_register_cfg_hooks ();
+  bitmap_obstack_initialize (NULL);
+  execute_pass_list (all_lowering_passes);
+  if (optimize && cgraph_global_info_ready)
+    execute_pass_list (pass_early_local_passes.sub);
+  free_dominance_info (CDI_POST_DOMINATORS);
+  free_dominance_info (CDI_DOMINATORS);
+  compact_blocks ();
+  current_function_decl = saved_current_function_decl;
+  bitmap_obstack_release (NULL);
+  pop_cfun ();
 }
-
 \f
 /* For functions-as-trees languages, this performs all optimization and
    compilation for FNDECL.  */
@@ -570,12 +374,17 @@ void
 tree_rest_of_compilation (tree fndecl)
 {
   location_t saved_loc;
-  struct cgraph_node *saved_node = NULL, *node;
+  struct cgraph_node *node;
 
   timevar_push (TV_EXPAND);
 
   gcc_assert (!flag_unit_at_a_time || cgraph_global_info_ready);
 
+  node = cgraph_node (fndecl);
+
+  /* Initialize the default bitmap obstack.  */
+  bitmap_obstack_initialize (NULL);
+
   /* Initialize the RTL code for the function.  */
   current_function_decl = fndecl;
   saved_loc = input_location;
@@ -587,80 +396,20 @@ tree_rest_of_compilation (tree fndecl)
      We haven't necessarily assigned RTL to all variables yet, so it's
      not safe to try to expand expressions involving them.  */
   cfun->x_dont_save_pending_sizes_p = 1;
+  
+  tree_register_cfg_hooks ();
 
-  node = cgraph_node (fndecl);
-
-  /* We might need the body of this function so that we can expand
-     it inline somewhere else.  This means not lowering some constructs
-     such as exception handling.  */
-  if (cgraph_preserve_function_body_p (fndecl))
-    {
-      if (!flag_unit_at_a_time)
-       {
-         struct cgraph_edge *e;
-
-         saved_node = cgraph_clone_node (node);
-         for (e = saved_node->callees; e; e = e->next_callee)
-           if (!e->inline_failed)
-             cgraph_clone_inlined_nodes (e, true);
-       }
-      cfun->saved_static_chain_decl = cfun->static_chain_decl;
-      cfun->saved_tree = save_body (fndecl, &cfun->saved_args,
-                                   &cfun->saved_static_chain_decl);
-    }
-
-  if (flag_inline_trees)
-    {
-      struct cgraph_edge *e;
-      for (e = node->callees; e; e = e->next_callee)
-       if (!e->inline_failed || warn_inline)
-         break;
-      if (e)
-       {
-         timevar_push (TV_INTEGRATION);
-         optimize_inline_calls (fndecl);
-         timevar_pop (TV_INTEGRATION);
-       }
-    }
-
-  /* We are not going to maintain the cgraph edges up to date.
-     Kill it so it won't confuse us.  */
-  while (node->callees)
-    cgraph_remove_edge (node->callees);
-
-  if (!vars_to_rename)
-    vars_to_rename = BITMAP_XMALLOC ();
-
+  bitmap_obstack_initialize (&reg_obstack); /* FIXME, only at RTL generation*/
   /* Perform all tree transforms and optimizations.  */
   execute_pass_list (all_passes);
+  
+  bitmap_obstack_release (&reg_obstack);
 
-  /* Restore original body if still needed.  */
-  if (cfun->saved_tree)
-    {
-      DECL_SAVED_TREE (fndecl) = cfun->saved_tree;
-      DECL_ARGUMENTS (fndecl) = cfun->saved_args;
-      cfun->static_chain_decl = cfun->saved_static_chain_decl;
-
-      /* When not in unit-at-a-time mode, we must preserve out of line copy
-        representing node before inlining.  Restore original outgoing edges
-        using clone we created earlier.  */
-      if (!flag_unit_at_a_time)
-       {
-         struct cgraph_edge *e;
-
-         while (node->callees)
-           cgraph_remove_edge (node->callees);
-         node->callees = saved_node->callees;
-         saved_node->callees = NULL;
-         update_inlined_to_pointers (node, node);
-         for (e = node->callees; e; e = e->next_callee)
-           e->caller = node;
-         cgraph_remove_node (saved_node);
-       }
-    }
-  else
-    DECL_SAVED_TREE (fndecl) = NULL;
-  cfun = 0;
+  /* Release the default bitmap obstack.  */
+  bitmap_obstack_release (NULL);
+  
+  DECL_SAVED_TREE (fndecl) = NULL;
+  set_cfun (NULL);
 
   /* If requested, warn about function definitions where the function will
      return a value (usually of some struct or union type) which itself will
@@ -678,11 +427,11 @@ tree_rest_of_compilation (tree fndecl)
            = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type));
 
          if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0)
-           warning ("%Jsize of return value of '%D' is %u bytes",
-                     fndecl, fndecl, size_as_int);
+           warning (OPT_Wlarger_than_eq, "size of return value of %q+D is %u bytes",
+                     fndecl, size_as_int);
          else
-           warning ("%Jsize of return value of '%D' is larger than %wd bytes",
-                     fndecl, fndecl, larger_than_size);
+           warning (OPT_Wlarger_than_eq, "size of return value of %q+D is larger than %wd bytes",
+                     fndecl, larger_than_size);
        }
     }