--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/cgraphunit.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,1600 @@
+/* Callgraph based interprocedural optimizations.
+   Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
+   Free Software Foundation, Inc.
+   Contributed by Jan Hubicka
+
+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/>.  */
+
+/* This module implements main driver of compilation process as well as
+   few basic interprocedural optimizers.
+
+   The main scope of this file is to act as an interface in between
+   tree based frontends and the backend (and middle end)
+
+   The front-end is supposed to use following functionality:
+
+    - cgraph_finalize_function
+
+      This function is called once front-end has parsed whole body of function
+      and it is certain that the function body nor the declaration will change.
+
+      (There is one exception needed for implementing GCC extern inline
+	function.)
+
+    - varpool_finalize_variable
+
+      This function has same behavior as the above but is used for static
+      variables.
+
+    - cgraph_finalize_compilation_unit
+
+      This function is called once (source level) compilation unit is finalized
+      and it will no longer change.
+
+      In the the call-graph construction and local function
+      analysis takes place here.  Bodies of unreachable functions are released
+      to conserve memory usage.
+
+      The function can be called multiple times when multiple source level
+      compilation units are combined (such as in C frontend)
+
+    - cgraph_optimize
+
+      In this unit-at-a-time compilation the intra procedural analysis takes
+      place here.  In particular the static functions whose address is never
+      taken are marked as local.  Backend can then use this information to
+      modify calling conventions, do better inlining or similar optimizations.
+
+    - cgraph_mark_needed_node
+    - varpool_mark_needed_node
+
+      When function or variable is referenced by some hidden way the call-graph
+      data structure must be updated accordingly by this function.
+      There should be little need to call this function and all the references
+      should be made explicit to cgraph code.  At present these functions are
+      used by C++ frontend to explicitly mark the keyed methods.
+
+    - analyze_expr callback
+
+      This function is responsible for lowering tree nodes not understood by
+      generic code into understandable ones or alternatively marking
+      callgraph and varpool nodes referenced by the as needed.
+
+      ??? On the tree-ssa genericizing should take place here and we will avoid
+      need for these hooks (replacing them by genericizing hook)
+
+        Analyzing of all functions is deferred
+	to cgraph_finalize_compilation_unit and expansion into cgraph_optimize.
+
+	In cgraph_finalize_compilation_unit the reachable functions are
+	analyzed.  During analysis the call-graph edges from reachable
+	functions are constructed and their destinations are marked as
+	reachable.  References to functions and variables are discovered too
+	and variables found to be needed output to the assembly file.  Via
+	mark_referenced call in assemble_variable functions referenced by
+	static variables are noticed too.
+
+	The intra-procedural information is produced and its existence
+	indicated by global_info_ready.  Once this flag is set it is impossible
+	to change function from !reachable to reachable and thus
+	assemble_variable no longer call mark_referenced.
+
+	Finally the call-graph is topologically sorted and all reachable functions
+	that has not been completely inlined or are not external are output.
+
+	??? It is possible that reference to function or variable is optimized
+	out.  We can not deal with this nicely because topological order is not
+	suitable for it.  For tree-ssa we may consider another pass doing
+	optimization and re-discovering reachable functions.
+
+	??? Reorganize code so variables are output very last and only if they
+	really has been referenced by produced code, so we catch more cases
+	where reference has been optimized out.  */
+
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "rtl.h"
+#include "tree-flow.h"
+#include "tree-inline.h"
+#include "langhooks.h"
+#include "pointer-set.h"
+#include "toplev.h"
+#include "flags.h"
+#include "ggc.h"
+#include "debug.h"
+#include "target.h"
+#include "cgraph.h"
+#include "diagnostic.h"
+#include "timevar.h"
+#include "params.h"
+#include "fibheap.h"
+#include "c-common.h"
+#include "intl.h"
+#include "function.h"
+#include "ipa-prop.h"
+#include "gimple.h"
+#include "tree-iterator.h"
+#include "tree-pass.h"
+#include "output.h"
+
+static void cgraph_expand_all_functions (void);
+static void cgraph_mark_functions_to_output (void);
+static void cgraph_expand_function (struct cgraph_node *);
+static void cgraph_output_pending_asms (void);
+
+static FILE *cgraph_dump_file;
+
+/* A vector of FUNCTION_DECLs declared as static constructors.  */
+static GTY (()) VEC(tree, gc) *static_ctors;
+/* A vector of FUNCTION_DECLs declared as static destructors.  */
+static GTY (()) VEC(tree, gc) *static_dtors;
+
+/* When target does not have ctors and dtors, we call all constructor
+   and destructor by special initialization/destruction function
+   recognized by collect2.  
+   
+   When we are going to build this function, collect all constructors and
+   destructors and turn them into normal functions.  */
+
+static void
+record_cdtor_fn (tree fndecl)
+{
+  struct cgraph_node *node;
+  if (targetm.have_ctors_dtors
+      || (!DECL_STATIC_CONSTRUCTOR (fndecl)
+	  && !DECL_STATIC_DESTRUCTOR (fndecl)))
+    return;
+
+  if (DECL_STATIC_CONSTRUCTOR (fndecl))
+    {
+      VEC_safe_push (tree, gc, static_ctors, fndecl);
+      DECL_STATIC_CONSTRUCTOR (fndecl) = 0;
+    }
+  if (DECL_STATIC_DESTRUCTOR (fndecl))
+    {
+      VEC_safe_push (tree, gc, static_dtors, fndecl);
+      DECL_STATIC_DESTRUCTOR (fndecl) = 0;
+    }
+  node = cgraph_node (fndecl);
+  node->local.disregard_inline_limits = 1;
+  cgraph_mark_reachable_node (node);
+}
+
+/* Define global constructors/destructor functions for the CDTORS, of
+   which they are LEN.  The CDTORS are sorted by initialization
+   priority.  If CTOR_P is true, these are constructors; otherwise,
+   they are destructors.  */
+
+static void
+build_cdtor (bool ctor_p, tree *cdtors, size_t len)
+{
+  size_t i;
+
+  i = 0;
+  while (i < len)
+    {
+      tree body;
+      tree fn;
+      priority_type priority;
+
+      priority = 0;
+      body = NULL_TREE;
+      /* Find the next batch of constructors/destructors with the same
+	 initialization priority.  */
+      do
+	{
+	  priority_type p;
+	  fn = cdtors[i];
+	  p = ctor_p ? DECL_INIT_PRIORITY (fn) : DECL_FINI_PRIORITY (fn);
+	  if (!body)
+	    priority = p;
+	  else if (p != priority)
+	    break;
+	  append_to_statement_list (build_function_call_expr (fn, 0),
+				    &body);
+	  ++i;
+	}
+      while (i < len);
+      gcc_assert (body != NULL_TREE);
+      /* Generate a function to call all the function of like
+	 priority.  */
+      cgraph_build_static_cdtor (ctor_p ? 'I' : 'D', body, priority);
+    }
+}
+
+/* Comparison function for qsort.  P1 and P2 are actually of type
+   "tree *" and point to static constructors.  DECL_INIT_PRIORITY is
+   used to determine the sort order.  */
+
+static int
+compare_ctor (const void *p1, const void *p2)
+{
+  tree f1;
+  tree f2;
+  int priority1;
+  int priority2;
+
+  f1 = *(const tree *)p1;
+  f2 = *(const tree *)p2;
+  priority1 = DECL_INIT_PRIORITY (f1);
+  priority2 = DECL_INIT_PRIORITY (f2);
+  
+  if (priority1 < priority2)
+    return -1;
+  else if (priority1 > priority2)
+    return 1;
+  else
+    /* Ensure a stable sort.  */
+    return (const tree *)p1 - (const tree *)p2;
+}
+
+/* Comparison function for qsort.  P1 and P2 are actually of type
+   "tree *" and point to static destructors.  DECL_FINI_PRIORITY is
+   used to determine the sort order.  */
+
+static int
+compare_dtor (const void *p1, const void *p2)
+{
+  tree f1;
+  tree f2;
+  int priority1;
+  int priority2;
+
+  f1 = *(const tree *)p1;
+  f2 = *(const tree *)p2;
+  priority1 = DECL_FINI_PRIORITY (f1);
+  priority2 = DECL_FINI_PRIORITY (f2);
+  
+  if (priority1 < priority2)
+    return -1;
+  else if (priority1 > priority2)
+    return 1;
+  else
+    /* Ensure a stable sort.  */
+    return (const tree *)p1 - (const tree *)p2;
+}
+
+/* Generate functions to call static constructors and destructors
+   for targets that do not support .ctors/.dtors sections.  These
+   functions have magic names which are detected by collect2.  */
+
+static void
+cgraph_build_cdtor_fns (void)
+{
+  if (!VEC_empty (tree, static_ctors))
+    {
+      gcc_assert (!targetm.have_ctors_dtors);
+      qsort (VEC_address (tree, static_ctors),
+	     VEC_length (tree, static_ctors), 
+	     sizeof (tree),
+	     compare_ctor);
+      build_cdtor (/*ctor_p=*/true,
+		   VEC_address (tree, static_ctors),
+		   VEC_length (tree, static_ctors)); 
+      VEC_truncate (tree, static_ctors, 0);
+    }
+
+  if (!VEC_empty (tree, static_dtors))
+    {
+      gcc_assert (!targetm.have_ctors_dtors);
+      qsort (VEC_address (tree, static_dtors),
+	     VEC_length (tree, static_dtors), 
+	     sizeof (tree),
+	     compare_dtor);
+      build_cdtor (/*ctor_p=*/false,
+		   VEC_address (tree, static_dtors),
+		   VEC_length (tree, static_dtors)); 
+      VEC_truncate (tree, static_dtors, 0);
+    }
+}
+
+/* Determine if function DECL is needed.  That is, visible to something
+   either outside this translation unit, something magic in the system
+   configury.  */
+
+static bool
+decide_is_function_needed (struct cgraph_node *node, tree decl)
+{
+  if (MAIN_NAME_P (DECL_NAME (decl))
+      && TREE_PUBLIC (decl))
+    {
+      node->local.externally_visible = true;
+      return true;
+    }
+
+  /* If the user told us it is used, then it must be so.  */
+  if (node->local.externally_visible)
+    return true;
+
+  /* ??? If the assembler name is set by hand, it is possible to assemble
+     the name later after finalizing the function and the fact is noticed
+     in assemble_name then.  This is arguably a bug.  */
+  if (DECL_ASSEMBLER_NAME_SET_P (decl)
+      && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
+    return true;
+
+  /* With -fkeep-inline-functions we are keeping all inline functions except
+     for extern inline ones.  */
+  if (flag_keep_inline_functions
+      && DECL_DECLARED_INLINE_P (decl)
+      && !DECL_EXTERNAL (decl)
+      && !lookup_attribute ("always_inline", DECL_ATTRIBUTES (decl)))
+     return true;
+
+  /* If we decided it was needed before, but at the time we didn't have
+     the body of the function available, then it's still needed.  We have
+     to go back and re-check its dependencies now.  */
+  if (node->needed)
+    return true;
+
+  /* Externally visible functions must be output.  The exception is
+     COMDAT functions that must be output only when they are needed.
+
+     When not optimizing, also output the static functions. (see
+     PR24561), but don't do so for always_inline functions, functions
+     declared inline and nested functions.  These was optimized out
+     in the original implementation and it is unclear whether we want
+     to change the behavior here.  */
+  if (((TREE_PUBLIC (decl)
+	|| (!optimize && !node->local.disregard_inline_limits
+	    && !DECL_DECLARED_INLINE_P (decl)
+	    && !node->origin))
+      && !flag_whole_program)
+      && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
+    return true;
+
+  /* Constructors and destructors are reachable from the runtime by
+     some mechanism.  */
+  if (DECL_STATIC_CONSTRUCTOR (decl) || DECL_STATIC_DESTRUCTOR (decl))
+    return true;
+
+  return false;
+}
+
+/* Process CGRAPH_NEW_FUNCTIONS and perform actions necessary to add these
+   functions into callgraph in a way so they look like ordinary reachable
+   functions inserted into callgraph already at construction time.  */
+
+bool
+cgraph_process_new_functions (void)
+{
+  bool output = false;
+  tree fndecl;
+  struct cgraph_node *node;
+
+  /*  Note that this queue may grow as its being processed, as the new
+      functions may generate new ones.  */
+  while (cgraph_new_nodes)
+    {
+      node = cgraph_new_nodes;
+      fndecl = node->decl;
+      cgraph_new_nodes = cgraph_new_nodes->next_needed;
+      switch (cgraph_state)
+	{
+	case CGRAPH_STATE_CONSTRUCTION:
+	  /* At construction time we just need to finalize function and move
+	     it into reachable functions list.  */
+
+	  node->next_needed = NULL;
+	  cgraph_finalize_function (fndecl, false);
+	  cgraph_mark_reachable_node (node);
+	  output = true;
+	  break;
+
+	case CGRAPH_STATE_IPA:
+	case CGRAPH_STATE_IPA_SSA:
+	  /* When IPA optimization already started, do all essential
+	     transformations that has been already performed on the whole
+	     cgraph but not on this function.  */
+
+	  gimple_register_cfg_hooks ();
+	  if (!node->analyzed)
+	    cgraph_analyze_function (node);
+	  push_cfun (DECL_STRUCT_FUNCTION (fndecl));
+	  current_function_decl = fndecl;
+	  compute_inline_parameters (node);
+	  if ((cgraph_state == CGRAPH_STATE_IPA_SSA
+	      && !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (fndecl)))
+	      /* When not optimizing, be sure we run early local passes anyway
+		 to expand OMP.  */
+	      || !optimize)
+	    execute_pass_list (pass_early_local_passes.pass.sub);
+	  free_dominance_info (CDI_POST_DOMINATORS);
+	  free_dominance_info (CDI_DOMINATORS);
+	  pop_cfun ();
+	  current_function_decl = NULL;
+	  break;
+
+	case CGRAPH_STATE_EXPANSION:
+	  /* Functions created during expansion shall be compiled
+	     directly.  */
+	  node->output = 0;
+	  cgraph_expand_function (node);
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	  break;
+	}
+      cgraph_call_function_insertion_hooks (node);
+    }
+  return output;
+}
+
+/* As an GCC extension we allow redefinition of the function.  The
+   semantics when both copies of bodies differ is not well defined.
+   We replace the old body with new body so in unit at a time mode
+   we always use new body, while in normal mode we may end up with
+   old body inlined into some functions and new body expanded and
+   inlined in others.
+
+   ??? It may make more sense to use one body for inlining and other
+   body for expanding the function but this is difficult to do.  */
+
+static void
+cgraph_reset_node (struct cgraph_node *node)
+{
+  /* If node->output is set, then we have already begun whole-unit analysis.
+     This is *not* testing for whether we've already emitted the function.
+     That case can be sort-of legitimately seen with real function redefinition
+     errors.  I would argue that the front end should never present us with
+     such a case, but don't enforce that for now.  */
+  gcc_assert (!node->output);
+
+  /* Reset our data structures so we can analyze the function again.  */
+  memset (&node->local, 0, sizeof (node->local));
+  memset (&node->global, 0, sizeof (node->global));
+  memset (&node->rtl, 0, sizeof (node->rtl));
+  node->analyzed = false;
+  node->local.redefined_extern_inline = true;
+  node->local.finalized = false;
+
+  cgraph_node_remove_callees (node);
+
+  /* We may need to re-queue the node for assembling in case
+     we already proceeded it and ignored as not needed or got
+     a re-declaration in IMA mode.  */
+  if (node->reachable)
+    {
+      struct cgraph_node *n;
+
+      for (n = cgraph_nodes_queue; n; n = n->next_needed)
+	if (n == node)
+	  break;
+      if (!n)
+	node->reachable = 0;
+    }
+}
+
+static void
+cgraph_lower_function (struct cgraph_node *node)
+{
+  if (node->lowered)
+    return;
+  tree_lowering_passes (node->decl);
+  node->lowered = true;
+}
+
+/* DECL has been parsed.  Take it, queue it, compile it at the whim of the
+   logic in effect.  If NESTED is true, then our caller cannot stand to have
+   the garbage collector run at the moment.  We would need to either create
+   a new GC context, or just not compile right now.  */
+
+void
+cgraph_finalize_function (tree decl, bool nested)
+{
+  struct cgraph_node *node = cgraph_node (decl);
+
+  if (node->local.finalized)
+    cgraph_reset_node (node);
+
+  node->pid = cgraph_max_pid ++;
+  notice_global_symbol (decl);
+  node->local.finalized = true;
+  node->lowered = DECL_STRUCT_FUNCTION (decl)->cfg != NULL;
+  record_cdtor_fn (node->decl);
+  if (node->nested)
+    lower_nested_functions (decl);
+  gcc_assert (!node->nested);
+
+  if (decide_is_function_needed (node, decl))
+    cgraph_mark_needed_node (node);
+
+  /* Since we reclaim unreachable nodes at the end of every language
+     level unit, we need to be conservative about possible entry points
+     there.  */
+  if ((TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl)))
+    cgraph_mark_reachable_node (node);
+
+  /* If we've not yet emitted decl, tell the debug info about it.  */
+  if (!TREE_ASM_WRITTEN (decl))
+    (*debug_hooks->deferred_inline_function) (decl);
+
+  /* Possibly warn about unused parameters.  */
+  if (warn_unused_parameter)
+    do_warn_unused_parameter (decl);
+
+  if (!nested)
+    ggc_collect ();
+}
+
+/* C99 extern inline keywords allow changing of declaration after function
+   has been finalized.  We need to re-decide if we want to mark the function as
+   needed then.   */
+
+void
+cgraph_mark_if_needed (tree decl)
+{
+  struct cgraph_node *node = cgraph_node (decl);
+  if (node->local.finalized && decide_is_function_needed (node, decl))
+    cgraph_mark_needed_node (node);
+}
+
+/* Verify cgraph nodes of given cgraph node.  */
+void
+verify_cgraph_node (struct cgraph_node *node)
+{
+  struct cgraph_edge *e;
+  struct cgraph_node *main_clone;
+  struct function *this_cfun = DECL_STRUCT_FUNCTION (node->decl);
+  struct function *saved_cfun = cfun;
+  basic_block this_block;
+  gimple_stmt_iterator gsi;
+  bool error_found = false;
+
+  if (errorcount || sorrycount)
+    return;
+
+  timevar_push (TV_CGRAPH_VERIFY);
+  /* debug_generic_stmt needs correct cfun */
+  set_cfun (this_cfun);
+  for (e = node->callees; e; e = e->next_callee)
+    if (e->aux)
+      {
+	error ("aux field set for edge %s->%s",
+	       cgraph_node_name (e->caller), cgraph_node_name (e->callee));
+	error_found = true;
+      }
+  if (node->count < 0)
+    {
+      error ("Execution count is negative");
+      error_found = true;
+    }
+  for (e = node->callers; e; e = e->next_caller)
+    {
+      if (e->count < 0)
+	{
+	  error ("caller edge count is negative");
+	  error_found = true;
+	}
+      if (e->frequency < 0)
+	{
+	  error ("caller edge frequency is negative");
+	  error_found = true;
+	}
+      if (e->frequency > CGRAPH_FREQ_MAX)
+	{
+	  error ("caller edge frequency is too large");
+	  error_found = true;
+	}
+      if (!e->inline_failed)
+	{
+	  if (node->global.inlined_to
+	      != (e->caller->global.inlined_to
+		  ? e->caller->global.inlined_to : e->caller))
+	    {
+	      error ("inlined_to pointer is wrong");
+	      error_found = true;
+	    }
+	  if (node->callers->next_caller)
+	    {
+	      error ("multiple inline callers");
+	      error_found = true;
+	    }
+	}
+      else
+	if (node->global.inlined_to)
+	  {
+	    error ("inlined_to pointer set for noninline callers");
+	    error_found = true;
+	  }
+    }
+  if (!node->callers && node->global.inlined_to)
+    {
+      error ("inlined_to pointer is set but no predecessors found");
+      error_found = true;
+    }
+  if (node->global.inlined_to == node)
+    {
+      error ("inlined_to pointer refers to itself");
+      error_found = true;
+    }
+
+  for (main_clone = cgraph_node (node->decl); main_clone;
+       main_clone = main_clone->next_clone)
+    if (main_clone == node)
+      break;
+  if (!cgraph_node (node->decl))
+    {
+      error ("node not found in cgraph_hash");
+      error_found = true;
+    }
+
+  if (node->analyzed
+      && !TREE_ASM_WRITTEN (node->decl)
+      && (!DECL_EXTERNAL (node->decl) || node->global.inlined_to))
+    {
+      if (this_cfun->cfg)
+	{
+	  /* The nodes we're interested in are never shared, so walk
+	     the tree ignoring duplicates.  */
+	  struct pointer_set_t *visited_nodes = pointer_set_create ();
+	  /* Reach the trees by walking over the CFG, and note the
+	     enclosing basic-blocks in the call edges.  */
+	  FOR_EACH_BB_FN (this_block, this_cfun)
+	    for (gsi = gsi_start_bb (this_block);
+                 !gsi_end_p (gsi);
+                 gsi_next (&gsi))
+	      {
+		gimple stmt = gsi_stmt (gsi);
+		tree decl;
+		if (is_gimple_call (stmt) && (decl = gimple_call_fndecl (stmt)))
+		  {
+		    struct cgraph_edge *e = cgraph_edge (node, stmt);
+		    if (e)
+		      {
+			if (e->aux)
+			  {
+			    error ("shared call_stmt:");
+			    debug_gimple_stmt (stmt);
+			    error_found = true;
+			  }
+			if (e->callee->decl != cgraph_node (decl)->decl
+			    && e->inline_failed)
+			  {
+			    error ("edge points to wrong declaration:");
+			    debug_tree (e->callee->decl);
+			    fprintf (stderr," Instead of:");
+			    debug_tree (decl);
+			  }
+			e->aux = (void *)1;
+		      }
+		    else
+		      {
+			error ("missing callgraph edge for call stmt:");
+			debug_gimple_stmt (stmt);
+			error_found = true;
+		      }
+		  }
+	      }
+	  pointer_set_destroy (visited_nodes);
+	}
+      else
+	/* No CFG available?!  */
+	gcc_unreachable ();
+
+      for (e = node->callees; e; e = e->next_callee)
+	{
+	  if (!e->aux && !e->indirect_call)
+	    {
+	      error ("edge %s->%s has no corresponding call_stmt",
+		     cgraph_node_name (e->caller),
+		     cgraph_node_name (e->callee));
+	      debug_gimple_stmt (e->call_stmt);
+	      error_found = true;
+	    }
+	  e->aux = 0;
+	}
+    }
+  if (error_found)
+    {
+      dump_cgraph_node (stderr, node);
+      internal_error ("verify_cgraph_node failed");
+    }
+  set_cfun (saved_cfun);
+  timevar_pop (TV_CGRAPH_VERIFY);
+}
+
+/* Verify whole cgraph structure.  */
+void
+verify_cgraph (void)
+{
+  struct cgraph_node *node;
+
+  if (sorrycount || errorcount)
+    return;
+
+  for (node = cgraph_nodes; node; node = node->next)
+    verify_cgraph_node (node);
+}
+
+/* Output all asm statements we have stored up to be output.  */
+
+static void
+cgraph_output_pending_asms (void)
+{
+  struct cgraph_asm_node *can;
+
+  if (errorcount || sorrycount)
+    return;
+
+  for (can = cgraph_asm_nodes; can; can = can->next)
+    assemble_asm (can->asm_str);
+  cgraph_asm_nodes = NULL;
+}
+
+/* Analyze the function scheduled to be output.  */
+void
+cgraph_analyze_function (struct cgraph_node *node)
+{
+  tree decl = node->decl;
+
+  current_function_decl = decl;
+  push_cfun (DECL_STRUCT_FUNCTION (decl));
+  cgraph_lower_function (node);
+  node->analyzed = true;
+
+  pop_cfun ();
+  current_function_decl = NULL;
+}
+
+/* Look for externally_visible and used attributes and mark cgraph nodes
+   accordingly.
+
+   We cannot mark the nodes at the point the attributes are processed (in
+   handle_*_attribute) because the copy of the declarations available at that
+   point may not be canonical.  For example, in:
+
+    void f();
+    void f() __attribute__((used));
+
+   the declaration we see in handle_used_attribute will be the second
+   declaration -- but the front end will subsequently merge that declaration
+   with the original declaration and discard the second declaration.
+
+   Furthermore, we can't mark these nodes in cgraph_finalize_function because:
+
+    void f() {}
+    void f() __attribute__((externally_visible));
+
+   is valid.
+
+   So, we walk the nodes at the end of the translation unit, applying the
+   attributes at that point.  */
+
+static void
+process_function_and_variable_attributes (struct cgraph_node *first,
+                                          struct varpool_node *first_var)
+{
+  struct cgraph_node *node;
+  struct varpool_node *vnode;
+
+  for (node = cgraph_nodes; node != first; node = node->next)
+    {
+      tree decl = node->decl;
+      if (lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
+	{
+	  mark_decl_referenced (decl);
+	  if (node->local.finalized)
+	     cgraph_mark_needed_node (node);
+	}
+      if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
+	{
+	  if (! TREE_PUBLIC (node->decl))
+	    warning (OPT_Wattributes,
+		     "%J%<externally_visible%> attribute have effect only on public objects",
+		     node->decl);
+	  else
+	    {
+	      if (node->local.finalized)
+		cgraph_mark_needed_node (node);
+	      node->local.externally_visible = true;
+	    }
+	}
+    }
+  for (vnode = varpool_nodes; vnode != first_var; vnode = vnode->next)
+    {
+      tree decl = vnode->decl;
+      if (lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
+	{
+	  mark_decl_referenced (decl);
+	  if (vnode->finalized)
+	    varpool_mark_needed_node (vnode);
+	}
+      if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
+	{
+	  if (! TREE_PUBLIC (vnode->decl))
+	    warning (OPT_Wattributes,
+		     "%J%<externally_visible%> attribute have effect only on public objects",
+		     vnode->decl);
+	  else
+	    {
+	      if (vnode->finalized)
+		varpool_mark_needed_node (vnode);
+	      vnode->externally_visible = true;
+	    }
+	}
+    }
+}
+
+/* Process CGRAPH_NODES_NEEDED queue, analyze each function (and transitively
+   each reachable functions) and build cgraph.
+   The function can be called multiple times after inserting new nodes
+   into beginning of queue.  Just the new part of queue is re-scanned then.  */
+
+static void
+cgraph_analyze_functions (void)
+{
+  /* Keep track of already processed nodes when called multiple times for
+     intermodule optimization.  */
+  static struct cgraph_node *first_analyzed;
+  struct cgraph_node *first_processed = first_analyzed;
+  static struct varpool_node *first_analyzed_var;
+  struct cgraph_node *node, *next;
+
+  process_function_and_variable_attributes (first_processed,
+					    first_analyzed_var);
+  first_processed = cgraph_nodes;
+  first_analyzed_var = varpool_nodes;
+  varpool_analyze_pending_decls ();
+  if (cgraph_dump_file)
+    {
+      fprintf (cgraph_dump_file, "Initial entry points:");
+      for (node = cgraph_nodes; node != first_analyzed; node = node->next)
+	if (node->needed)
+	  fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+      fprintf (cgraph_dump_file, "\n");
+    }
+  cgraph_process_new_functions ();
+
+  /* Propagate reachability flag and lower representation of all reachable
+     functions.  In the future, lowering will introduce new functions and
+     new entry points on the way (by template instantiation and virtual
+     method table generation for instance).  */
+  while (cgraph_nodes_queue)
+    {
+      struct cgraph_edge *edge;
+      tree decl = cgraph_nodes_queue->decl;
+
+      node = cgraph_nodes_queue;
+      cgraph_nodes_queue = cgraph_nodes_queue->next_needed;
+      node->next_needed = NULL;
+
+      /* ??? It is possible to create extern inline function and later using
+	 weak alias attribute to kill its body. See
+	 gcc.c-torture/compile/20011119-1.c  */
+      if (!DECL_STRUCT_FUNCTION (decl))
+	{
+	  cgraph_reset_node (node);
+	  continue;
+	}
+
+      gcc_assert (!node->analyzed && node->reachable);
+      gcc_assert (gimple_body (decl));
+
+      cgraph_analyze_function (node);
+
+      for (edge = node->callees; edge; edge = edge->next_callee)
+	if (!edge->callee->reachable)
+	  cgraph_mark_reachable_node (edge->callee);
+
+      /* If decl is a clone of an abstract function, mark that abstract
+	 function so that we don't release its body. The DECL_INITIAL() of that
+         abstract function declaration will be later needed to output debug info.  */
+      if (DECL_ABSTRACT_ORIGIN (decl))
+	{
+	  struct cgraph_node *origin_node = cgraph_node (DECL_ABSTRACT_ORIGIN (decl));
+	  origin_node->abstract_and_needed = true;
+	}
+
+      /* We finalize local static variables during constructing callgraph
+         edges.  Process their attributes too.  */
+      process_function_and_variable_attributes (first_processed,
+						first_analyzed_var);
+      first_processed = cgraph_nodes;
+      first_analyzed_var = varpool_nodes;
+      varpool_analyze_pending_decls ();
+      cgraph_process_new_functions ();
+    }
+
+  /* Collect entry points to the unit.  */
+  if (cgraph_dump_file)
+    {
+      fprintf (cgraph_dump_file, "Unit entry points:");
+      for (node = cgraph_nodes; node != first_analyzed; node = node->next)
+	if (node->needed)
+	  fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+      fprintf (cgraph_dump_file, "\n\nInitial ");
+      dump_cgraph (cgraph_dump_file);
+    }
+
+  if (cgraph_dump_file)
+    fprintf (cgraph_dump_file, "\nReclaiming functions:");
+
+  for (node = cgraph_nodes; node != first_analyzed; node = next)
+    {
+      tree decl = node->decl;
+      next = node->next;
+
+      if (node->local.finalized && !gimple_has_body_p (decl))
+	cgraph_reset_node (node);
+
+      if (!node->reachable && gimple_has_body_p (decl))
+	{
+	  if (cgraph_dump_file)
+	    fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+	  cgraph_remove_node (node);
+	  continue;
+	}
+      else
+	node->next_needed = NULL;
+      gcc_assert (!node->local.finalized || gimple_has_body_p (decl));
+      gcc_assert (node->analyzed == node->local.finalized);
+    }
+  if (cgraph_dump_file)
+    {
+      fprintf (cgraph_dump_file, "\n\nReclaimed ");
+      dump_cgraph (cgraph_dump_file);
+    }
+  first_analyzed = cgraph_nodes;
+  ggc_collect ();
+}
+
+/* Analyze the whole compilation unit once it is parsed completely.  */
+
+void
+cgraph_finalize_compilation_unit (void)
+{
+  if (errorcount || sorrycount)
+    return;
+
+  finish_aliases_1 ();
+
+  if (!quiet_flag)
+    {
+      fprintf (stderr, "\nAnalyzing compilation unit\n");
+      fflush (stderr);
+    }
+
+  timevar_push (TV_CGRAPH);
+  cgraph_analyze_functions ();
+  timevar_pop (TV_CGRAPH);
+}
+/* Figure out what functions we want to assemble.  */
+
+static void
+cgraph_mark_functions_to_output (void)
+{
+  struct cgraph_node *node;
+
+  for (node = cgraph_nodes; node; node = node->next)
+    {
+      tree decl = node->decl;
+      struct cgraph_edge *e;
+
+      gcc_assert (!node->output);
+
+      for (e = node->callers; e; e = e->next_caller)
+	if (e->inline_failed)
+	  break;
+
+      /* We need to output all local functions that are used and not
+	 always inlined, as well as those that are reachable from
+	 outside the current compilation unit.  */
+      if (node->analyzed
+	  && !node->global.inlined_to
+	  && (node->needed
+	      || (e && node->reachable))
+	  && !TREE_ASM_WRITTEN (decl)
+	  && !DECL_EXTERNAL (decl))
+	node->output = 1;
+      else
+	{
+	  /* We should've reclaimed all functions that are not needed.  */
+#ifdef ENABLE_CHECKING
+	  if (!node->global.inlined_to
+	      && gimple_has_body_p (decl)
+	      && !DECL_EXTERNAL (decl))
+	    {
+	      dump_cgraph_node (stderr, node);
+	      internal_error ("failed to reclaim unneeded function");
+	    }
+#endif
+	  gcc_assert (node->global.inlined_to
+		      || !gimple_has_body_p (decl)
+		      || DECL_EXTERNAL (decl));
+
+	}
+
+    }
+}
+
+/* Expand function specified by NODE.  */
+
+static void
+cgraph_expand_function (struct cgraph_node *node)
+{
+  tree decl = node->decl;
+
+  /* We ought to not compile any inline clones.  */
+  gcc_assert (!node->global.inlined_to);
+
+  announce_function (decl);
+
+  gcc_assert (node->lowered);
+
+  /* Generate RTL for the body of DECL.  */
+  if (lang_hooks.callgraph.emit_associated_thunks)
+    lang_hooks.callgraph.emit_associated_thunks (decl);
+  tree_rest_of_compilation (decl);
+
+  /* Make sure that BE didn't give up on compiling.  */
+  gcc_assert (TREE_ASM_WRITTEN (decl));
+  current_function_decl = NULL;
+  gcc_assert (!cgraph_preserve_function_body_p (decl));
+  cgraph_release_function_body (node);
+  /* Eliminate all call edges.  This is important so the GIMPLE_CALL no longer
+     points to the dead function body.  */
+  cgraph_node_remove_callees (node);
+
+  cgraph_function_flags_ready = true;
+}
+
+/* Return true when CALLER_DECL should be inlined into CALLEE_DECL.  */
+
+bool
+cgraph_inline_p (struct cgraph_edge *e, const char **reason)
+{
+  *reason = e->inline_failed;
+  return !e->inline_failed;
+}
+
+
+
+/* Expand all functions that must be output.
+
+   Attempt to topologically sort the nodes so function is output when
+   all called functions are already assembled to allow data to be
+   propagated across the callgraph.  Use a stack to get smaller distance
+   between a function and its callees (later we may choose to use a more
+   sophisticated algorithm for function reordering; we will likely want
+   to use subsections to make the output functions appear in top-down
+   order).  */
+
+static void
+cgraph_expand_all_functions (void)
+{
+  struct cgraph_node *node;
+  struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
+  int order_pos, new_order_pos = 0;
+  int i;
+
+  order_pos = cgraph_postorder (order);
+  gcc_assert (order_pos == cgraph_n_nodes);
+
+  /* Garbage collector may remove inline clones we eliminate during
+     optimization.  So we must be sure to not reference them.  */
+  for (i = 0; i < order_pos; i++)
+    if (order[i]->output)
+      order[new_order_pos++] = order[i];
+
+  for (i = new_order_pos - 1; i >= 0; i--)
+    {
+      node = order[i];
+      if (node->output)
+	{
+	  gcc_assert (node->reachable);
+	  node->output = 0;
+	  cgraph_expand_function (node);
+	}
+    }
+  cgraph_process_new_functions ();
+
+  free (order);
+
+}
+
+/* This is used to sort the node types by the cgraph order number.  */
+
+struct cgraph_order_sort
+{
+  enum { ORDER_UNDEFINED = 0, ORDER_FUNCTION, ORDER_VAR, ORDER_ASM } kind;
+  union
+  {
+    struct cgraph_node *f;
+    struct varpool_node *v;
+    struct cgraph_asm_node *a;
+  } u;
+};
+
+/* Output all functions, variables, and asm statements in the order
+   according to their order fields, which is the order in which they
+   appeared in the file.  This implements -fno-toplevel-reorder.  In
+   this mode we may output functions and variables which don't really
+   need to be output.  */
+
+static void
+cgraph_output_in_order (void)
+{
+  int max;
+  size_t size;
+  struct cgraph_order_sort *nodes;
+  int i;
+  struct cgraph_node *pf;
+  struct varpool_node *pv;
+  struct cgraph_asm_node *pa;
+
+  max = cgraph_order;
+  size = max * sizeof (struct cgraph_order_sort);
+  nodes = (struct cgraph_order_sort *) alloca (size);
+  memset (nodes, 0, size);
+
+  varpool_analyze_pending_decls ();
+
+  for (pf = cgraph_nodes; pf; pf = pf->next)
+    {
+      if (pf->output)
+	{
+	  i = pf->order;
+	  gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
+	  nodes[i].kind = ORDER_FUNCTION;
+	  nodes[i].u.f = pf;
+	}
+    }
+
+  for (pv = varpool_nodes_queue; pv; pv = pv->next_needed)
+    {
+      i = pv->order;
+      gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
+      nodes[i].kind = ORDER_VAR;
+      nodes[i].u.v = pv;
+    }
+
+  for (pa = cgraph_asm_nodes; pa; pa = pa->next)
+    {
+      i = pa->order;
+      gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
+      nodes[i].kind = ORDER_ASM;
+      nodes[i].u.a = pa;
+    }
+
+  /* In toplevel reorder mode we output all statics; mark them as needed.  */
+  for (i = 0; i < max; ++i)
+    {
+      if (nodes[i].kind == ORDER_VAR)
+        {
+	  varpool_mark_needed_node (nodes[i].u.v);
+	}
+    }
+  varpool_empty_needed_queue ();
+
+  for (i = 0; i < max; ++i)
+    {
+      switch (nodes[i].kind)
+	{
+	case ORDER_FUNCTION:
+	  nodes[i].u.f->output = 0;
+	  cgraph_expand_function (nodes[i].u.f);
+	  break;
+
+	case ORDER_VAR:
+	  varpool_assemble_decl (nodes[i].u.v);
+	  break;
+
+	case ORDER_ASM:
+	  assemble_asm (nodes[i].u.a->asm_str);
+	  break;
+
+	case ORDER_UNDEFINED:
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	}
+    }
+
+  cgraph_asm_nodes = NULL;
+}
+
+/* Return true when function body of DECL still needs to be kept around
+   for later re-use.  */
+bool
+cgraph_preserve_function_body_p (tree decl)
+{
+  struct cgraph_node *node;
+
+  gcc_assert (cgraph_global_info_ready);
+  /* Look if there is any clone around.  */
+  for (node = cgraph_node (decl); node; node = node->next_clone)
+    if (node->global.inlined_to)
+      return true;
+  return false;
+}
+
+static void
+ipa_passes (void)
+{
+  set_cfun (NULL);
+  current_function_decl = NULL;
+  gimple_register_cfg_hooks ();
+  bitmap_obstack_initialize (NULL);
+  execute_ipa_pass_list (all_ipa_passes);
+  bitmap_obstack_release (NULL);
+}
+
+/* Perform simple optimizations based on callgraph.  */
+
+void
+cgraph_optimize (void)
+{
+  if (errorcount || sorrycount)
+    return;
+
+#ifdef ENABLE_CHECKING
+  verify_cgraph ();
+#endif
+
+  /* Call functions declared with the "constructor" or "destructor"
+     attribute.  */
+  cgraph_build_cdtor_fns ();
+
+  /* Frontend may output common variables after the unit has been finalized.
+     It is safe to deal with them here as they are always zero initialized.  */
+  varpool_analyze_pending_decls ();
+  cgraph_analyze_functions ();
+
+  timevar_push (TV_CGRAPHOPT);
+  if (pre_ipa_mem_report)
+    {
+      fprintf (stderr, "Memory consumption before IPA\n");
+      dump_memory_report (false);
+    }
+  if (!quiet_flag)
+    fprintf (stderr, "Performing interprocedural optimizations\n");
+  cgraph_state = CGRAPH_STATE_IPA;
+
+  /* Don't run the IPA passes if there was any error or sorry messages.  */
+  if (errorcount == 0 && sorrycount == 0)
+    ipa_passes ();
+
+  /* This pass remove bodies of extern inline functions we never inlined.
+     Do this later so other IPA passes see what is really going on.  */
+  cgraph_remove_unreachable_nodes (false, dump_file);
+  cgraph_global_info_ready = true;
+  if (cgraph_dump_file)
+    {
+      fprintf (cgraph_dump_file, "Optimized ");
+      dump_cgraph (cgraph_dump_file);
+      dump_varpool (cgraph_dump_file);
+    }
+  if (post_ipa_mem_report)
+    {
+      fprintf (stderr, "Memory consumption after IPA\n");
+      dump_memory_report (false);
+    }
+  timevar_pop (TV_CGRAPHOPT);
+
+  /* Output everything.  */
+  if (!quiet_flag)
+    fprintf (stderr, "Assembling functions:\n");
+#ifdef ENABLE_CHECKING
+  verify_cgraph ();
+#endif
+
+  cgraph_mark_functions_to_output ();
+
+  cgraph_state = CGRAPH_STATE_EXPANSION;
+  if (!flag_toplevel_reorder)
+    cgraph_output_in_order ();
+  else
+    {
+      cgraph_output_pending_asms ();
+
+      cgraph_expand_all_functions ();
+      varpool_remove_unreferenced_decls ();
+
+      varpool_assemble_pending_decls ();
+    }
+  cgraph_process_new_functions ();
+  cgraph_state = CGRAPH_STATE_FINISHED;
+
+  if (cgraph_dump_file)
+    {
+      fprintf (cgraph_dump_file, "\nFinal ");
+      dump_cgraph (cgraph_dump_file);
+    }
+#ifdef ENABLE_CHECKING
+  verify_cgraph ();
+  /* Double check that all inline clones are gone and that all
+     function bodies have been released from memory.  */
+  if (!(sorrycount || errorcount))
+    {
+      struct cgraph_node *node;
+      bool error_found = false;
+
+      for (node = cgraph_nodes; node; node = node->next)
+	if (node->analyzed
+	    && (node->global.inlined_to
+		|| gimple_has_body_p (node->decl)))
+	  {
+	    error_found = true;
+	    dump_cgraph_node (stderr, node);
+	  }
+      if (error_found)
+	internal_error ("nodes with unreleased memory found");
+    }
+#endif
+}
+/* Generate and emit a static constructor or destructor.  WHICH must
+   be one of 'I' (for a constructor) or 'D' (for a destructor).  BODY
+   is a STATEMENT_LIST containing GENERIC statements.  PRIORITY is the
+   initialization priority for this constructor or destructor.  */
+
+void
+cgraph_build_static_cdtor (char which, tree body, int priority)
+{
+  static int counter = 0;
+  char which_buf[16];
+  tree decl, name, resdecl;
+
+  /* The priority is encoded in the constructor or destructor name.
+     collect2 will sort the names and arrange that they are called at
+     program startup.  */
+  sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++);
+  name = get_file_function_name (which_buf);
+
+  decl = build_decl (FUNCTION_DECL, name,
+		     build_function_type (void_type_node, void_list_node));
+  current_function_decl = decl;
+
+  resdecl = build_decl (RESULT_DECL, NULL_TREE, void_type_node);
+  DECL_ARTIFICIAL (resdecl) = 1;
+  DECL_RESULT (decl) = resdecl;
+
+  allocate_struct_function (decl, false);
+
+  TREE_STATIC (decl) = 1;
+  TREE_USED (decl) = 1;
+  DECL_ARTIFICIAL (decl) = 1;
+  DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
+  DECL_SAVED_TREE (decl) = body;
+  TREE_PUBLIC (decl) = ! targetm.have_ctors_dtors;
+  DECL_UNINLINABLE (decl) = 1;
+
+  DECL_INITIAL (decl) = make_node (BLOCK);
+  TREE_USED (DECL_INITIAL (decl)) = 1;
+
+  DECL_SOURCE_LOCATION (decl) = input_location;
+  cfun->function_end_locus = input_location;
+
+  switch (which)
+    {
+    case 'I':
+      DECL_STATIC_CONSTRUCTOR (decl) = 1;
+      decl_init_priority_insert (decl, priority);
+      break;
+    case 'D':
+      DECL_STATIC_DESTRUCTOR (decl) = 1;
+      decl_fini_priority_insert (decl, priority);
+      break;
+    default:
+      gcc_unreachable ();
+    }
+
+  gimplify_function_tree (decl);
+
+  cgraph_add_new_function (decl, false);
+  cgraph_mark_needed_node (cgraph_node (decl));
+  set_cfun (NULL);
+}
+
+void
+init_cgraph (void)
+{
+  cgraph_dump_file = dump_begin (TDI_cgraph, NULL);
+}
+
+/* The edges representing the callers of the NEW_VERSION node were
+   fixed by cgraph_function_versioning (), now the call_expr in their
+   respective tree code should be updated to call the NEW_VERSION.  */
+
+static void
+update_call_expr (struct cgraph_node *new_version)
+{
+  struct cgraph_edge *e;
+
+  gcc_assert (new_version);
+
+  /* Update the call expr on the edges to call the new version.  */
+  for (e = new_version->callers; e; e = e->next_caller)
+    {
+      struct function *inner_function = DECL_STRUCT_FUNCTION (e->caller->decl);
+      gimple_call_set_fndecl (e->call_stmt, new_version->decl);
+      /* Update EH information too, just in case.  */
+      if (!stmt_could_throw_p (e->call_stmt)
+          && lookup_stmt_eh_region_fn (inner_function, e->call_stmt))
+        remove_stmt_from_eh_region_fn (inner_function, e->call_stmt);
+    }
+}
+
+
+/* Create a new cgraph node which is the new version of
+   OLD_VERSION node.  REDIRECT_CALLERS holds the callers
+   edges which should be redirected to point to
+   NEW_VERSION.  ALL the callees edges of OLD_VERSION
+   are cloned to the new version node.  Return the new
+   version node.  */
+
+static struct cgraph_node *
+cgraph_copy_node_for_versioning (struct cgraph_node *old_version,
+				 tree new_decl,
+				 VEC(cgraph_edge_p,heap) *redirect_callers)
+ {
+   struct cgraph_node *new_version;
+   struct cgraph_edge *e, *new_e;
+   struct cgraph_edge *next_callee;
+   unsigned i;
+
+   gcc_assert (old_version);
+
+   new_version = cgraph_node (new_decl);
+
+   new_version->analyzed = true;
+   new_version->local = old_version->local;
+   new_version->global = old_version->global;
+   new_version->rtl = new_version->rtl;
+   new_version->reachable = true;
+   new_version->count = old_version->count;
+
+   /* Clone the old node callees.  Recursive calls are
+      also cloned.  */
+   for (e = old_version->callees;e; e=e->next_callee)
+     {
+       new_e = cgraph_clone_edge (e, new_version, e->call_stmt, 0, e->frequency,
+				  e->loop_nest, true);
+       new_e->count = e->count;
+     }
+   /* Fix recursive calls.
+      If OLD_VERSION has a recursive call after the
+      previous edge cloning, the new version will have an edge
+      pointing to the old version, which is wrong;
+      Redirect it to point to the new version. */
+   for (e = new_version->callees ; e; e = next_callee)
+     {
+       next_callee = e->next_callee;
+       if (e->callee == old_version)
+	 cgraph_redirect_edge_callee (e, new_version);
+
+       if (!next_callee)
+	 break;
+     }
+   for (i = 0; VEC_iterate (cgraph_edge_p, redirect_callers, i, e); i++)
+     {
+       /* Redirect calls to the old version node to point to its new
+	  version.  */
+       cgraph_redirect_edge_callee (e, new_version);
+     }
+
+   return new_version;
+ }
+
+ /* Perform function versioning.
+    Function versioning includes copying of the tree and
+    a callgraph update (creating a new cgraph node and updating
+    its callees and callers).
+
+    REDIRECT_CALLERS varray includes the edges to be redirected
+    to the new version.
+
+    TREE_MAP is a mapping of tree nodes we want to replace with
+    new ones (according to results of prior analysis).
+    OLD_VERSION_NODE is the node that is versioned.
+    It returns the new version's cgraph node. 
+    ARGS_TO_SKIP lists arguments to be omitted from functions
+    */
+
+struct cgraph_node *
+cgraph_function_versioning (struct cgraph_node *old_version_node,
+			    VEC(cgraph_edge_p,heap) *redirect_callers,
+			    varray_type tree_map,
+			    bitmap args_to_skip)
+{
+  tree old_decl = old_version_node->decl;
+  struct cgraph_node *new_version_node = NULL;
+  tree new_decl;
+
+  if (!tree_versionable_function_p (old_decl))
+    return NULL;
+
+  /* Make a new FUNCTION_DECL tree node for the
+     new version. */
+  if (!args_to_skip)
+    new_decl = copy_node (old_decl);
+  else
+    new_decl = build_function_decl_skip_args (old_decl, args_to_skip);
+
+  /* Create the new version's call-graph node.
+     and update the edges of the new node. */
+  new_version_node =
+    cgraph_copy_node_for_versioning (old_version_node, new_decl,
+				     redirect_callers);
+
+  /* Copy the OLD_VERSION_NODE function tree to the new version.  */
+  tree_function_versioning (old_decl, new_decl, tree_map, false, args_to_skip);
+
+  /* Update the new version's properties.
+     Make The new version visible only within this translation unit.  Make sure
+     that is not weak also.
+     ??? We cannot use COMDAT linkage because there is no
+     ABI support for this.  */
+  DECL_EXTERNAL (new_version_node->decl) = 0;
+  DECL_ONE_ONLY (new_version_node->decl) = 0;
+  TREE_PUBLIC (new_version_node->decl) = 0;
+  DECL_COMDAT (new_version_node->decl) = 0;
+  DECL_WEAK (new_version_node->decl) = 0;
+  DECL_VIRTUAL_P (new_version_node->decl) = 0;
+  new_version_node->local.externally_visible = 0;
+  new_version_node->local.local = 1;
+  new_version_node->lowered = true;
+
+  /* Update the call_expr on the edges to call the new version node. */
+  update_call_expr (new_version_node);
+  
+  cgraph_call_function_insertion_hooks (new_version_node);
+  return new_version_node;
+}
+
+/* Produce separate function body for inline clones so the offline copy can be
+   modified without affecting them.  */
+struct cgraph_node *
+save_inline_function_body (struct cgraph_node *node)
+{
+  struct cgraph_node *first_clone;
+
+  gcc_assert (node == cgraph_node (node->decl));
+
+  cgraph_lower_function (node);
+
+  first_clone = node->next_clone;
+
+  first_clone->decl = copy_node (node->decl);
+  node->next_clone = NULL;
+  first_clone->prev_clone = NULL;
+  cgraph_insert_node_to_hashtable (first_clone);
+  gcc_assert (first_clone == cgraph_node (first_clone->decl));
+
+  /* Copy the OLD_VERSION_NODE function tree to the new version.  */
+  tree_function_versioning (node->decl, first_clone->decl, NULL, true, NULL);
+
+  DECL_EXTERNAL (first_clone->decl) = 0;
+  DECL_ONE_ONLY (first_clone->decl) = 0;
+  TREE_PUBLIC (first_clone->decl) = 0;
+  DECL_COMDAT (first_clone->decl) = 0;
+
+  for (node = first_clone->next_clone; node; node = node->next_clone)
+    node->decl = first_clone->decl;
+#ifdef ENABLE_CHECKING
+  verify_cgraph_node (first_clone);
+#endif
+  return first_clone;
+}
+
+#include "gt-cgraphunit.h"