diff gcc/tree-optimize.c @ 0:a06113de4d67

first commit
author kent <kent@cr.ie.u-ryukyu.ac.jp>
date Fri, 17 Jul 2009 14:47:48 +0900
parents
children 77e2b8dfacca
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/tree-optimize.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,470 @@
+/* Top-level control of tree optimizations.
+   Copyright 2001, 2002, 2003, 2004, 2005, 2007, 2008
+   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 3, or (at your option)
+any later version.
+
+GCC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+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 COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "rtl.h"
+#include "tm_p.h"
+#include "hard-reg-set.h"
+#include "basic-block.h"
+#include "output.h"
+#include "expr.h"
+#include "diagnostic.h"
+#include "basic-block.h"
+#include "flags.h"
+#include "tree-flow.h"
+#include "tree-dump.h"
+#include "timevar.h"
+#include "function.h"
+#include "langhooks.h"
+#include "toplev.h"
+#include "flags.h"
+#include "cgraph.h"
+#include "tree-inline.h"
+#include "tree-mudflap.h"
+#include "tree-pass.h"
+#include "ggc.h"
+#include "cgraph.h"
+#include "graph.h"
+#include "cfgloop.h"
+#include "except.h"
+
+
+/* Gate: execute, or not, all of the non-trivial optimizations.  */
+
+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)));
+}
+
+struct gimple_opt_pass pass_all_optimizations =
+{
+ {
+  GIMPLE_PASS,
+  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 */
+ }
+};
+
+/* Gate: execute, or not, all of the non-trivial optimizations.  */
+
+static bool
+gate_all_early_local_passes (void)
+{
+	  /* Don't bother doing anything if the program has errors.  */
+  return (!errorcount && !sorrycount);
+}
+
+struct simple_ipa_opt_pass pass_early_local_passes =
+{
+ {
+  SIMPLE_IPA_PASS,
+  "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 */
+  0,					/* properties_provided */
+  0,					/* properties_destroyed */
+  0,					/* todo_flags_start */
+  TODO_remove_functions	 		/* todo_flags_finish */
+ }
+};
+
+static unsigned int
+execute_early_local_optimizations (void)
+{
+  /* First time we start with early optimization we need to advance
+     cgraph state so newly inserted functions are also early optimized.
+     However we execute early local optimizations for lately inserted
+     functions, in that case don't reset cgraph state back to IPA_SSA.  */
+  if (cgraph_state < CGRAPH_STATE_IPA_SSA)
+    cgraph_state = CGRAPH_STATE_IPA_SSA;
+  return 0;
+}
+
+/* Gate: execute, or not, all of the non-trivial optimizations.  */
+
+static bool
+gate_all_early_optimizations (void)
+{
+  return (optimize >= 1
+	  /* Don't bother doing anything if the program has errors.  */
+	  && !(errorcount || sorrycount));
+}
+
+struct gimple_opt_pass pass_all_early_optimizations =
+{
+ {
+  GIMPLE_PASS,
+  "early_optimizations",		/* name */
+  gate_all_early_optimizations,		/* gate */
+  execute_early_local_optimizations,	/* 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 */
+ }
+};
+
+/* 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_pre_ipa (void)
+{
+  cleanup_tree_cfg ();
+  return 0;
+}
+
+struct gimple_opt_pass pass_cleanup_cfg =
+{
+ {
+  GIMPLE_PASS,
+  "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 */
+ }
+};
+
+
+/* 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;
+}
+
+struct gimple_opt_pass pass_cleanup_cfg_post_optimizing =
+{
+ {
+  GIMPLE_PASS,
+  "final_cleanup",			/* name */
+  NULL,					/* gate */
+  execute_cleanup_cfg_post_optimizing,	/* 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 */
+ }
+};
+
+/* Pass: do the actions required to finish with tree-ssa optimization
+   passes.  */
+
+static unsigned int
+execute_free_datastructures (void)
+{
+  free_dominance_info (CDI_DOMINATORS);
+  free_dominance_info (CDI_POST_DOMINATORS);
+
+  /* Remove the ssa structures.  */
+  if (cfun->gimple_df)
+    delete_tree_ssa ();
+  return 0;
+}
+
+struct gimple_opt_pass pass_free_datastructures =
+{
+ {
+  GIMPLE_PASS,
+  NULL,					/* name */
+  NULL,					/* gate */
+  execute_free_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 */
+ }
+};
+/* Pass: free cfg annotations.  */
+
+static unsigned int
+execute_free_cfg_annotations (void)
+{
+  /* And get rid of annotations we no longer need.  */
+  delete_tree_cfg_annotations ();
+
+  return 0;
+}
+
+struct gimple_opt_pass pass_free_cfg_annotations =
+{
+ {
+  GIMPLE_PASS,
+  NULL,					/* name */
+  NULL,					/* gate */
+  execute_free_cfg_annotations,		/* 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 */
+ }
+};
+
+/* 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.
+
+   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.  */
+
+unsigned int
+execute_fixup_cfg (void)
+{
+  basic_block bb;
+  gimple_stmt_iterator gsi;
+  int todo = gimple_in_ssa_p (cfun) ? TODO_verify_ssa : 0;
+
+  cfun->after_inlining = true;
+  cfun->always_inline_functions_inlined = true;
+
+  if (cfun->eh)
+    FOR_EACH_BB (bb)
+      {
+	for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	  {
+	    gimple stmt = gsi_stmt (gsi);
+	    tree decl = is_gimple_call (stmt)
+	                ? gimple_call_fndecl (stmt)
+			: NULL;
+
+	    if (decl
+		&& gimple_call_flags (stmt) & (ECF_CONST
+					       | ECF_PURE 
+					       | ECF_LOOPING_CONST_OR_PURE))
+	      {
+		if (gimple_in_ssa_p (cfun))
+		  {
+		    todo |= TODO_update_ssa | TODO_cleanup_cfg;
+	            update_stmt (stmt);
+		  }
+	      }
+
+	    if (!stmt_could_throw_p (stmt) && lookup_stmt_eh_region (stmt))
+	      remove_stmt_from_eh_region (stmt);
+	  }
+
+	if (gimple_purge_dead_eh_edges (bb))
+          todo |= TODO_cleanup_cfg;
+      }
+
+  /* Dump a textual representation of the flowgraph.  */
+  if (dump_file)
+    gimple_dump_cfg (dump_file, dump_flags);
+
+  return todo;
+}
+
+/* Do the actions required to initialize internal data structures used
+   in tree-ssa optimization passes.  */
+
+static unsigned int
+execute_init_datastructures (void)
+{
+  /* Allocate hash tables, arrays and other structures.  */
+  init_tree_ssa (cfun);
+  return 0;
+}
+
+struct gimple_opt_pass pass_init_datastructures =
+{
+ {
+  GIMPLE_PASS,
+  NULL,					/* name */
+  NULL,					/* 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 */
+ }
+};
+
+void
+tree_lowering_passes (tree fn)
+{
+  tree saved_current_function_decl = current_function_decl;
+
+  current_function_decl = fn;
+  push_cfun (DECL_STRUCT_FUNCTION (fn));
+  gimple_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.pass.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 ();
+}
+
+/* For functions-as-trees languages, this performs all optimization and
+   compilation for FNDECL.  */
+
+void
+tree_rest_of_compilation (tree fndecl)
+{
+  location_t saved_loc;
+  struct cgraph_node *node;
+
+  timevar_push (TV_EXPAND);
+
+  gcc_assert (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;
+  input_location = DECL_SOURCE_LOCATION (fndecl);
+  init_function_start (fndecl);
+
+  /* Even though we're inside a function body, we still don't want to
+     call expand_expr to calculate the size of a variable-sized array.
+     We haven't necessarily assigned RTL to all variables yet, so it's
+     not safe to try to expand expressions involving them.  */
+  cfun->dont_save_pending_sizes_p = 1;
+  
+  gimple_register_cfg_hooks ();
+
+  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);
+
+  /* Release the default bitmap obstack.  */
+  bitmap_obstack_release (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
+     take up a lot of stack space.  */
+  if (warn_larger_than && !DECL_EXTERNAL (fndecl) && TREE_TYPE (fndecl))
+    {
+      tree ret_type = TREE_TYPE (TREE_TYPE (fndecl));
+
+      if (ret_type && TYPE_SIZE_UNIT (ret_type)
+	  && TREE_CODE (TYPE_SIZE_UNIT (ret_type)) == INTEGER_CST
+	  && 0 < compare_tree_int (TYPE_SIZE_UNIT (ret_type),
+				   larger_than_size))
+	{
+	  unsigned int size_as_int
+	    = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type));
+
+	  if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0)
+	    warning (OPT_Wlarger_than_eq, "size of return value of %q+D is %u bytes",
+                     fndecl, size_as_int);
+	  else
+	    warning (OPT_Wlarger_than_eq, "size of return value of %q+D is larger than %wd bytes",
+                     fndecl, larger_than_size);
+	}
+    }
+
+  gimple_set_body (fndecl, NULL);
+  if (DECL_STRUCT_FUNCTION (fndecl) == 0
+      && !cgraph_node (fndecl)->origin)
+    {
+      /* Stop pointing to the local nodes about to be freed.
+	 But DECL_INITIAL must remain nonzero so we know this
+	 was an actual function definition.
+	 For a nested function, this is done in c_pop_function_context.
+	 If rest_of_compilation set this to 0, leave it 0.  */
+      if (DECL_INITIAL (fndecl) != 0)
+	DECL_INITIAL (fndecl) = error_mark_node;
+    }
+
+  input_location = saved_loc;
+
+  ggc_collect ();
+  timevar_pop (TV_EXPAND);
+}