--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/cfg.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,1300 @@
+/* Control flow graph manipulation code for GNU compiler.
+   Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+   Free Software Foundation, Inc.
+
+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 file contains low level functions to manipulate the CFG and
+   analyze it.  All other modules should not transform the data structure
+   directly and use abstraction instead.  The file is supposed to be
+   ordered bottom-up and should not contain any code dependent on a
+   particular intermediate language (RTL or trees).
+
+   Available functionality:
+     - Initialization/deallocation
+	 init_flow, clear_edges
+     - Low level basic block manipulation
+	 alloc_block, expunge_block
+     - Edge manipulation
+	 make_edge, make_single_succ_edge, cached_make_edge, remove_edge
+	 - Low level edge redirection (without updating instruction chain)
+	     redirect_edge_succ, redirect_edge_succ_nodup, redirect_edge_pred
+     - Dumping and debugging
+	 dump_flow_info, debug_flow_info, dump_edge_info
+     - Allocation of AUX fields for basic blocks
+	 alloc_aux_for_blocks, free_aux_for_blocks, alloc_aux_for_block
+     - clear_bb_flags
+     - Consistency checking
+	 verify_flow_info
+     - Dumping and debugging
+	 print_rtl_with_bb, dump_bb, debug_bb, debug_bb_n
+ */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "rtl.h"
+#include "hard-reg-set.h"
+#include "regs.h"
+#include "flags.h"
+#include "output.h"
+#include "function.h"
+#include "except.h"
+#include "toplev.h"
+#include "tm_p.h"
+#include "obstack.h"
+#include "timevar.h"
+#include "tree-pass.h"
+#include "ggc.h"
+#include "hashtab.h"
+#include "alloc-pool.h"
+#include "df.h"
+#include "cfgloop.h"
+#include "tree-flow.h"
+
+/* The obstack on which the flow graph components are allocated.  */
+
+struct bitmap_obstack reg_obstack;
+
+void debug_flow_info (void);
+static void free_edge (edge);
+
+#define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
+
+/* Called once at initialization time.  */
+
+void
+init_flow (struct function *the_fun)
+{
+  if (!the_fun->cfg)
+    the_fun->cfg = GGC_CNEW (struct control_flow_graph);
+  n_edges_for_function (the_fun) = 0;
+  ENTRY_BLOCK_PTR_FOR_FUNCTION (the_fun)
+    = GGC_CNEW (struct basic_block_def);
+  ENTRY_BLOCK_PTR_FOR_FUNCTION (the_fun)->index = ENTRY_BLOCK;
+  EXIT_BLOCK_PTR_FOR_FUNCTION (the_fun)
+    = GGC_CNEW (struct basic_block_def);
+  EXIT_BLOCK_PTR_FOR_FUNCTION (the_fun)->index = EXIT_BLOCK;
+  ENTRY_BLOCK_PTR_FOR_FUNCTION (the_fun)->next_bb 
+    = EXIT_BLOCK_PTR_FOR_FUNCTION (the_fun);
+  EXIT_BLOCK_PTR_FOR_FUNCTION (the_fun)->prev_bb 
+    = ENTRY_BLOCK_PTR_FOR_FUNCTION (the_fun);
+}
+
+/* Helper function for remove_edge and clear_edges.  Frees edge structure
+   without actually unlinking it from the pred/succ lists.  */
+
+static void
+free_edge (edge e ATTRIBUTE_UNUSED)
+{
+  n_edges--;
+  ggc_free (e);
+}
+
+/* Free the memory associated with the edge structures.  */
+
+void
+clear_edges (void)
+{
+  basic_block bb;
+  edge e;
+  edge_iterator ei;
+
+  FOR_EACH_BB (bb)
+    {
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	free_edge (e);
+      VEC_truncate (edge, bb->succs, 0);
+      VEC_truncate (edge, bb->preds, 0);
+    }
+
+  FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
+    free_edge (e);
+  VEC_truncate (edge, EXIT_BLOCK_PTR->preds, 0);
+  VEC_truncate (edge, ENTRY_BLOCK_PTR->succs, 0);
+
+  gcc_assert (!n_edges);
+}
+
+/* Allocate memory for basic_block.  */
+
+basic_block
+alloc_block (void)
+{
+  basic_block bb;
+  bb = GGC_CNEW (struct basic_block_def);
+  return bb;
+}
+
+/* Link block B to chain after AFTER.  */
+void
+link_block (basic_block b, basic_block after)
+{
+  b->next_bb = after->next_bb;
+  b->prev_bb = after;
+  after->next_bb = b;
+  b->next_bb->prev_bb = b;
+}
+
+/* Unlink block B from chain.  */
+void
+unlink_block (basic_block b)
+{
+  b->next_bb->prev_bb = b->prev_bb;
+  b->prev_bb->next_bb = b->next_bb;
+  b->prev_bb = NULL;
+  b->next_bb = NULL;
+}
+
+/* Sequentially order blocks and compact the arrays.  */
+void
+compact_blocks (void)
+{
+  int i;
+
+  SET_BASIC_BLOCK (ENTRY_BLOCK, ENTRY_BLOCK_PTR);
+  SET_BASIC_BLOCK (EXIT_BLOCK, EXIT_BLOCK_PTR);
+  
+  if (df)
+    df_compact_blocks ();
+  else 
+    {
+      basic_block bb;
+      
+      i = NUM_FIXED_BLOCKS;
+      FOR_EACH_BB (bb)
+	{
+	  SET_BASIC_BLOCK (i, bb);
+	  bb->index = i;
+	  i++;
+	}
+      gcc_assert (i == n_basic_blocks);
+
+      for (; i < last_basic_block; i++)
+	SET_BASIC_BLOCK (i, NULL);
+    }
+  last_basic_block = n_basic_blocks;
+}
+
+/* Remove block B from the basic block array.  */
+
+void
+expunge_block (basic_block b)
+{
+  unlink_block (b);
+  SET_BASIC_BLOCK (b->index, NULL);
+  n_basic_blocks--;
+  /* We should be able to ggc_free here, but we are not.
+     The dead SSA_NAMES are left pointing to dead statements that are pointing
+     to dead basic blocks making garbage collector to die.
+     We should be able to release all dead SSA_NAMES and at the same time we should
+     clear out BB pointer of dead statements consistently.  */
+}
+
+/* Connect E to E->src.  */
+
+static inline void
+connect_src (edge e)
+{
+  VEC_safe_push (edge, gc, e->src->succs, e);
+  df_mark_solutions_dirty ();
+}
+
+/* Connect E to E->dest.  */
+
+static inline void
+connect_dest (edge e)
+{
+  basic_block dest = e->dest;
+  VEC_safe_push (edge, gc, dest->preds, e);
+  e->dest_idx = EDGE_COUNT (dest->preds) - 1;
+  df_mark_solutions_dirty ();
+}
+
+/* Disconnect edge E from E->src.  */
+
+static inline void
+disconnect_src (edge e)
+{
+  basic_block src = e->src;
+  edge_iterator ei;
+  edge tmp;
+
+  for (ei = ei_start (src->succs); (tmp = ei_safe_edge (ei)); )
+    {
+      if (tmp == e)
+	{
+	  VEC_unordered_remove (edge, src->succs, ei.index);
+	  return;
+	}
+      else
+	ei_next (&ei);
+    }
+
+  df_mark_solutions_dirty ();
+  gcc_unreachable ();
+}
+
+/* Disconnect edge E from E->dest.  */
+
+static inline void
+disconnect_dest (edge e)
+{
+  basic_block dest = e->dest;
+  unsigned int dest_idx = e->dest_idx;
+
+  VEC_unordered_remove (edge, dest->preds, dest_idx);
+
+  /* If we removed an edge in the middle of the edge vector, we need
+     to update dest_idx of the edge that moved into the "hole".  */
+  if (dest_idx < EDGE_COUNT (dest->preds))
+    EDGE_PRED (dest, dest_idx)->dest_idx = dest_idx;
+  df_mark_solutions_dirty ();
+}
+
+/* Create an edge connecting SRC and DEST with flags FLAGS.  Return newly
+   created edge.  Use this only if you are sure that this edge can't
+   possibly already exist.  */
+
+edge
+unchecked_make_edge (basic_block src, basic_block dst, int flags)
+{
+  edge e;
+  e = GGC_CNEW (struct edge_def);
+  n_edges++;
+
+  e->src = src;
+  e->dest = dst;
+  e->flags = flags;
+
+  connect_src (e);
+  connect_dest (e);
+
+  execute_on_growing_pred (e);
+  return e;
+}
+
+/* Create an edge connecting SRC and DST with FLAGS optionally using
+   edge cache CACHE.  Return the new edge, NULL if already exist.  */
+
+edge
+cached_make_edge (sbitmap edge_cache, basic_block src, basic_block dst, int flags)
+{
+  if (edge_cache == NULL
+      || src == ENTRY_BLOCK_PTR
+      || dst == EXIT_BLOCK_PTR)
+    return make_edge (src, dst, flags);
+
+  /* Does the requested edge already exist?  */
+  if (! TEST_BIT (edge_cache, dst->index))
+    {
+      /* The edge does not exist.  Create one and update the
+	 cache.  */
+      SET_BIT (edge_cache, dst->index);
+      return unchecked_make_edge (src, dst, flags);
+    }
+
+  /* At this point, we know that the requested edge exists.  Adjust
+     flags if necessary.  */
+  if (flags)
+    {
+      edge e = find_edge (src, dst);
+      e->flags |= flags;
+    }
+
+  return NULL;
+}
+
+/* Create an edge connecting SRC and DEST with flags FLAGS.  Return newly
+   created edge or NULL if already exist.  */
+
+edge
+make_edge (basic_block src, basic_block dest, int flags)
+{
+  edge e = find_edge (src, dest);
+
+  /* Make sure we don't add duplicate edges.  */
+  if (e)
+    {
+      e->flags |= flags;
+      return NULL;
+    }
+
+  return unchecked_make_edge (src, dest, flags);
+}
+
+/* Create an edge connecting SRC to DEST and set probability by knowing
+   that it is the single edge leaving SRC.  */
+
+edge
+make_single_succ_edge (basic_block src, basic_block dest, int flags)
+{
+  edge e = make_edge (src, dest, flags);
+
+  e->probability = REG_BR_PROB_BASE;
+  e->count = src->count;
+  return e;
+}
+
+/* This function will remove an edge from the flow graph.  */
+
+void
+remove_edge_raw (edge e)
+{
+  remove_predictions_associated_with_edge (e);
+  execute_on_shrinking_pred (e);
+
+  disconnect_src (e);
+  disconnect_dest (e);
+
+  /* This is probably not needed, but it doesn't hurt.  */
+  redirect_edge_var_map_clear (e);
+
+  free_edge (e);
+}
+
+/* Redirect an edge's successor from one block to another.  */
+
+void
+redirect_edge_succ (edge e, basic_block new_succ)
+{
+  execute_on_shrinking_pred (e);
+
+  disconnect_dest (e);
+
+  e->dest = new_succ;
+
+  /* Reconnect the edge to the new successor block.  */
+  connect_dest (e);
+
+  execute_on_growing_pred (e);
+}
+
+/* Like previous but avoid possible duplicate edge.  */
+
+edge
+redirect_edge_succ_nodup (edge e, basic_block new_succ)
+{
+  edge s;
+
+  s = find_edge (e->src, new_succ);
+  if (s && s != e)
+    {
+      s->flags |= e->flags;
+      s->probability += e->probability;
+      if (s->probability > REG_BR_PROB_BASE)
+	s->probability = REG_BR_PROB_BASE;
+      s->count += e->count;
+      remove_edge (e);
+      redirect_edge_var_map_dup (s, e);
+      e = s;
+    }
+  else
+    redirect_edge_succ (e, new_succ);
+
+  return e;
+}
+
+/* Redirect an edge's predecessor from one block to another.  */
+
+void
+redirect_edge_pred (edge e, basic_block new_pred)
+{
+  disconnect_src (e);
+
+  e->src = new_pred;
+
+  /* Reconnect the edge to the new predecessor block.  */
+  connect_src (e);
+}
+
+/* Clear all basic block flags, with the exception of partitioning and
+   setjmp_target.  */
+void
+clear_bb_flags (void)
+{
+  basic_block bb;
+
+  FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
+    bb->flags = (BB_PARTITION (bb)  
+		 | (bb->flags & (BB_DISABLE_SCHEDULE + BB_RTL + BB_NON_LOCAL_GOTO_TARGET)));
+}
+
+/* Check the consistency of profile information.  We can't do that
+   in verify_flow_info, as the counts may get invalid for incompletely
+   solved graphs, later eliminating of conditionals or roundoff errors.
+   It is still practical to have them reported for debugging of simple
+   testcases.  */
+void
+check_bb_profile (basic_block bb, FILE * file)
+{
+  edge e;
+  int sum = 0;
+  gcov_type lsum;
+  edge_iterator ei;
+
+  if (profile_status == PROFILE_ABSENT)
+    return;
+
+  if (bb != EXIT_BLOCK_PTR)
+    {
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	sum += e->probability;
+      if (EDGE_COUNT (bb->succs) && abs (sum - REG_BR_PROB_BASE) > 100)
+	fprintf (file, "Invalid sum of outgoing probabilities %.1f%%\n",
+		 sum * 100.0 / REG_BR_PROB_BASE);
+      lsum = 0;
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	lsum += e->count;
+      if (EDGE_COUNT (bb->succs)
+	  && (lsum - bb->count > 100 || lsum - bb->count < -100))
+	fprintf (file, "Invalid sum of outgoing counts %i, should be %i\n",
+		 (int) lsum, (int) bb->count);
+    }
+  if (bb != ENTRY_BLOCK_PTR)
+    {
+      sum = 0;
+      FOR_EACH_EDGE (e, ei, bb->preds)
+	sum += EDGE_FREQUENCY (e);
+      if (abs (sum - bb->frequency) > 100)
+	fprintf (file,
+		 "Invalid sum of incoming frequencies %i, should be %i\n",
+		 sum, bb->frequency);
+      lsum = 0;
+      FOR_EACH_EDGE (e, ei, bb->preds)
+	lsum += e->count;
+      if (lsum - bb->count > 100 || lsum - bb->count < -100)
+	fprintf (file, "Invalid sum of incoming counts %i, should be %i\n",
+		 (int) lsum, (int) bb->count);
+    }
+}
+
+/* Write information about registers and basic blocks into FILE.
+   This is part of making a debugging dump.  */
+
+void
+dump_regset (regset r, FILE *outf)
+{
+  unsigned i;
+  reg_set_iterator rsi;
+
+  if (r == NULL)
+    {
+      fputs (" (nil)", outf);
+      return;
+    }
+
+  EXECUTE_IF_SET_IN_REG_SET (r, 0, i, rsi)
+    {
+      fprintf (outf, " %d", i);
+      if (i < FIRST_PSEUDO_REGISTER)
+	fprintf (outf, " [%s]",
+		 reg_names[i]);
+    }
+}
+
+/* Print a human-readable representation of R on the standard error
+   stream.  This function is designed to be used from within the
+   debugger.  */
+
+void
+debug_regset (regset r)
+{
+  dump_regset (r, stderr);
+  putc ('\n', stderr);
+}
+
+/* Emit basic block information for BB.  HEADER is true if the user wants
+   the generic information and the predecessors, FOOTER is true if they want
+   the successors.  FLAGS is the dump flags of interest; TDF_DETAILS emit
+   global register liveness information.  PREFIX is put in front of every
+   line.  The output is emitted to FILE.  */
+void
+dump_bb_info (basic_block bb, bool header, bool footer, int flags,
+	      const char *prefix, FILE *file)
+{
+  edge e;
+  edge_iterator ei;
+
+  if (header)
+    {
+      fprintf (file, "\n%sBasic block %d ", prefix, bb->index);
+      if (bb->prev_bb)
+        fprintf (file, ", prev %d", bb->prev_bb->index);
+      if (bb->next_bb)
+        fprintf (file, ", next %d", bb->next_bb->index);
+      fprintf (file, ", loop_depth %d, count ", bb->loop_depth);
+      fprintf (file, HOST_WIDEST_INT_PRINT_DEC, bb->count);
+      fprintf (file, ", freq %i", bb->frequency);
+      /* Both maybe_hot_bb_p & probably_never_executed_bb_p functions
+	 crash without cfun. */ 
+      if (cfun && maybe_hot_bb_p (bb))
+	fprintf (file, ", maybe hot");
+      if (cfun && probably_never_executed_bb_p (bb))
+	fprintf (file, ", probably never executed");
+      fprintf (file, ".\n");
+
+      fprintf (file, "%sPredecessors: ", prefix);
+      FOR_EACH_EDGE (e, ei, bb->preds)
+	dump_edge_info (file, e, 0);
+
+      if ((flags & TDF_DETAILS)
+	  && (bb->flags & BB_RTL)
+	  && df)
+	{
+	  fprintf (file, "\n");
+	  df_dump_top (bb, file);
+	}
+   }
+
+  if (footer)
+    {
+      fprintf (file, "\n%sSuccessors: ", prefix);
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	dump_edge_info (file, e, 1);
+
+      if ((flags & TDF_DETAILS)
+	  && (bb->flags & BB_RTL)
+	  && df)
+	{
+	  fprintf (file, "\n");
+	  df_dump_bottom (bb, file);
+	}
+   }
+
+  putc ('\n', file);
+}
+
+/* Dump the register info to FILE.  */
+
+void 
+dump_reg_info (FILE *file)
+{
+  unsigned int i, max = max_reg_num ();
+  if (reload_completed)
+    return;
+
+  if (reg_info_p_size < max)
+    max = reg_info_p_size;
+
+  fprintf (file, "%d registers.\n", max);
+  for (i = FIRST_PSEUDO_REGISTER; i < max; i++)
+    {
+      enum reg_class rclass, altclass;
+      
+      if (regstat_n_sets_and_refs)
+	fprintf (file, "\nRegister %d used %d times across %d insns",
+		 i, REG_N_REFS (i), REG_LIVE_LENGTH (i));
+      else if (df)
+	fprintf (file, "\nRegister %d used %d times across %d insns",
+		 i, DF_REG_USE_COUNT (i) + DF_REG_DEF_COUNT (i), REG_LIVE_LENGTH (i));
+      
+      if (REG_BASIC_BLOCK (i) >= NUM_FIXED_BLOCKS)
+	fprintf (file, " in block %d", REG_BASIC_BLOCK (i));
+      if (regstat_n_sets_and_refs)
+	fprintf (file, "; set %d time%s", REG_N_SETS (i),
+		 (REG_N_SETS (i) == 1) ? "" : "s");
+      else if (df)
+	fprintf (file, "; set %d time%s", DF_REG_DEF_COUNT (i),
+		 (DF_REG_DEF_COUNT (i) == 1) ? "" : "s");
+      if (regno_reg_rtx[i] != NULL && REG_USERVAR_P (regno_reg_rtx[i]))
+	fprintf (file, "; user var");
+      if (REG_N_DEATHS (i) != 1)
+	fprintf (file, "; dies in %d places", REG_N_DEATHS (i));
+      if (REG_N_CALLS_CROSSED (i) == 1)
+	fprintf (file, "; crosses 1 call");
+      else if (REG_N_CALLS_CROSSED (i))
+	fprintf (file, "; crosses %d calls", REG_N_CALLS_CROSSED (i));
+      if (REG_FREQ_CALLS_CROSSED (i))
+	fprintf (file, "; crosses call with %d frequency", REG_FREQ_CALLS_CROSSED (i));
+      if (regno_reg_rtx[i] != NULL
+	  && PSEUDO_REGNO_BYTES (i) != UNITS_PER_WORD)
+	fprintf (file, "; %d bytes", PSEUDO_REGNO_BYTES (i));
+      
+      rclass = reg_preferred_class (i);
+      altclass = reg_alternate_class (i);
+      if (rclass != GENERAL_REGS || altclass != ALL_REGS)
+	{
+	  if (altclass == ALL_REGS || rclass == ALL_REGS)
+	    fprintf (file, "; pref %s", reg_class_names[(int) rclass]);
+	  else if (altclass == NO_REGS)
+	    fprintf (file, "; %s or none", reg_class_names[(int) rclass]);
+	  else
+	    fprintf (file, "; pref %s, else %s",
+		     reg_class_names[(int) rclass],
+		     reg_class_names[(int) altclass]);
+	}
+      
+      if (regno_reg_rtx[i] != NULL && REG_POINTER (regno_reg_rtx[i]))
+	fprintf (file, "; pointer");
+      fprintf (file, ".\n");
+    }
+}
+
+
+void
+dump_flow_info (FILE *file, int flags)
+{
+  basic_block bb;
+
+  /* There are no pseudo registers after reload.  Don't dump them.  */
+  if (reg_info_p_size && (flags & TDF_DETAILS) != 0)
+    dump_reg_info (file);
+
+  fprintf (file, "\n%d basic blocks, %d edges.\n", n_basic_blocks, n_edges);
+  FOR_ALL_BB (bb)
+    {
+      dump_bb_info (bb, true, true, flags, "", file);
+      check_bb_profile (bb, file);
+    }
+
+  putc ('\n', file);
+}
+
+void
+debug_flow_info (void)
+{
+  dump_flow_info (stderr, TDF_DETAILS);
+}
+
+void
+dump_edge_info (FILE *file, edge e, int do_succ)
+{
+  basic_block side = (do_succ ? e->dest : e->src);
+  /* both ENTRY_BLOCK_PTR & EXIT_BLOCK_PTR depend upon cfun. */
+  if (cfun && side == ENTRY_BLOCK_PTR)
+    fputs (" ENTRY", file);
+  else if (cfun && side == EXIT_BLOCK_PTR)
+    fputs (" EXIT", file);
+  else
+    fprintf (file, " %d", side->index);
+
+  if (e->probability)
+    fprintf (file, " [%.1f%%] ", e->probability * 100.0 / REG_BR_PROB_BASE);
+
+  if (e->count)
+    {
+      fprintf (file, " count:");
+      fprintf (file, HOST_WIDEST_INT_PRINT_DEC, e->count);
+    }
+
+  if (e->flags)
+    {
+      static const char * const bitnames[] = {
+	"fallthru", "ab", "abcall", "eh", "fake", "dfs_back",
+	"can_fallthru", "irreducible", "sibcall", "loop_exit",
+	"true", "false", "exec"
+      };
+      int comma = 0;
+      int i, flags = e->flags;
+
+      fputs (" (", file);
+      for (i = 0; flags; i++)
+	if (flags & (1 << i))
+	  {
+	    flags &= ~(1 << i);
+
+	    if (comma)
+	      fputc (',', file);
+	    if (i < (int) ARRAY_SIZE (bitnames))
+	      fputs (bitnames[i], file);
+	    else
+	      fprintf (file, "%d", i);
+	    comma = 1;
+	  }
+
+      fputc (')', file);
+    }
+}
+
+/* Simple routines to easily allocate AUX fields of basic blocks.  */
+
+static struct obstack block_aux_obstack;
+static void *first_block_aux_obj = 0;
+static struct obstack edge_aux_obstack;
+static void *first_edge_aux_obj = 0;
+
+/* Allocate a memory block of SIZE as BB->aux.  The obstack must
+   be first initialized by alloc_aux_for_blocks.  */
+
+inline void
+alloc_aux_for_block (basic_block bb, int size)
+{
+  /* Verify that aux field is clear.  */
+  gcc_assert (!bb->aux && first_block_aux_obj);
+  bb->aux = obstack_alloc (&block_aux_obstack, size);
+  memset (bb->aux, 0, size);
+}
+
+/* Initialize the block_aux_obstack and if SIZE is nonzero, call
+   alloc_aux_for_block for each basic block.  */
+
+void
+alloc_aux_for_blocks (int size)
+{
+  static int initialized;
+
+  if (!initialized)
+    {
+      gcc_obstack_init (&block_aux_obstack);
+      initialized = 1;
+    }
+  else
+    /* Check whether AUX data are still allocated.  */
+    gcc_assert (!first_block_aux_obj);
+
+  first_block_aux_obj = obstack_alloc (&block_aux_obstack, 0);
+  if (size)
+    {
+      basic_block bb;
+
+      FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
+	alloc_aux_for_block (bb, size);
+    }
+}
+
+/* Clear AUX pointers of all blocks.  */
+
+void
+clear_aux_for_blocks (void)
+{
+  basic_block bb;
+
+  FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
+    bb->aux = NULL;
+}
+
+/* Free data allocated in block_aux_obstack and clear AUX pointers
+   of all blocks.  */
+
+void
+free_aux_for_blocks (void)
+{
+  gcc_assert (first_block_aux_obj);
+  obstack_free (&block_aux_obstack, first_block_aux_obj);
+  first_block_aux_obj = NULL;
+
+  clear_aux_for_blocks ();
+}
+
+/* Allocate a memory edge of SIZE as BB->aux.  The obstack must
+   be first initialized by alloc_aux_for_edges.  */
+
+inline void
+alloc_aux_for_edge (edge e, int size)
+{
+  /* Verify that aux field is clear.  */
+  gcc_assert (!e->aux && first_edge_aux_obj);
+  e->aux = obstack_alloc (&edge_aux_obstack, size);
+  memset (e->aux, 0, size);
+}
+
+/* Initialize the edge_aux_obstack and if SIZE is nonzero, call
+   alloc_aux_for_edge for each basic edge.  */
+
+void
+alloc_aux_for_edges (int size)
+{
+  static int initialized;
+
+  if (!initialized)
+    {
+      gcc_obstack_init (&edge_aux_obstack);
+      initialized = 1;
+    }
+  else
+    /* Check whether AUX data are still allocated.  */
+    gcc_assert (!first_edge_aux_obj);
+
+  first_edge_aux_obj = obstack_alloc (&edge_aux_obstack, 0);
+  if (size)
+    {
+      basic_block bb;
+
+      FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+	{
+	  edge e;
+	  edge_iterator ei;
+
+	  FOR_EACH_EDGE (e, ei, bb->succs)
+	    alloc_aux_for_edge (e, size);
+	}
+    }
+}
+
+/* Clear AUX pointers of all edges.  */
+
+void
+clear_aux_for_edges (void)
+{
+  basic_block bb;
+  edge e;
+
+  FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+    {
+      edge_iterator ei;
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	e->aux = NULL;
+    }
+}
+
+/* Free data allocated in edge_aux_obstack and clear AUX pointers
+   of all edges.  */
+
+void
+free_aux_for_edges (void)
+{
+  gcc_assert (first_edge_aux_obj);
+  obstack_free (&edge_aux_obstack, first_edge_aux_obj);
+  first_edge_aux_obj = NULL;
+
+  clear_aux_for_edges ();
+}
+
+void
+debug_bb (basic_block bb)
+{
+  dump_bb (bb, stderr, 0);
+}
+
+basic_block
+debug_bb_n (int n)
+{
+  basic_block bb = BASIC_BLOCK (n);
+  dump_bb (bb, stderr, 0);
+  return bb;
+}
+
+/* Dumps cfg related information about basic block BB to FILE.  */
+
+static void
+dump_cfg_bb_info (FILE *file, basic_block bb)
+{
+  unsigned i;
+  edge_iterator ei;
+  bool first = true;
+  static const char * const bb_bitnames[] =
+    {
+      "new", "reachable", "irreducible_loop", "superblock",
+      "nosched", "hot", "cold", "dup", "xlabel", "rtl",
+      "fwdr", "nothrd"
+    };
+  const unsigned n_bitnames = sizeof (bb_bitnames) / sizeof (char *);
+  edge e;
+
+  fprintf (file, "Basic block %d", bb->index);
+  for (i = 0; i < n_bitnames; i++)
+    if (bb->flags & (1 << i))
+      {
+	if (first)
+	  fprintf (file, " (");
+	else
+	  fprintf (file, ", ");
+	first = false;
+	fprintf (file, bb_bitnames[i]);
+      }
+  if (!first)
+    fprintf (file, ")");
+  fprintf (file, "\n");
+
+  fprintf (file, "Predecessors: ");
+  FOR_EACH_EDGE (e, ei, bb->preds)
+    dump_edge_info (file, e, 0);
+
+  fprintf (file, "\nSuccessors: ");
+  FOR_EACH_EDGE (e, ei, bb->succs)
+    dump_edge_info (file, e, 1);
+  fprintf (file, "\n\n");
+}
+
+/* Dumps a brief description of cfg to FILE.  */
+
+void
+brief_dump_cfg (FILE *file)
+{
+  basic_block bb;
+
+  FOR_EACH_BB (bb)
+    {
+      dump_cfg_bb_info (file, bb);
+    }
+}
+
+/* An edge originally destinating BB of FREQUENCY and COUNT has been proved to
+   leave the block by TAKEN_EDGE.  Update profile of BB such that edge E can be
+   redirected to destination of TAKEN_EDGE.
+
+   This function may leave the profile inconsistent in the case TAKEN_EDGE
+   frequency or count is believed to be lower than FREQUENCY or COUNT
+   respectively.  */
+void
+update_bb_profile_for_threading (basic_block bb, int edge_frequency,
+				 gcov_type count, edge taken_edge)
+{
+  edge c;
+  int prob;
+  edge_iterator ei;
+
+  bb->count -= count;
+  if (bb->count < 0)
+    {
+      if (dump_file)
+	fprintf (dump_file, "bb %i count became negative after threading",
+		 bb->index);
+      bb->count = 0;
+    }
+
+  /* Compute the probability of TAKEN_EDGE being reached via threaded edge.
+     Watch for overflows.  */
+  if (bb->frequency)
+    prob = edge_frequency * REG_BR_PROB_BASE / bb->frequency;
+  else
+    prob = 0;
+  if (prob > taken_edge->probability)
+    {
+      if (dump_file)
+	fprintf (dump_file, "Jump threading proved probability of edge "
+		 "%i->%i too small (it is %i, should be %i).\n",
+		 taken_edge->src->index, taken_edge->dest->index,
+		 taken_edge->probability, prob);
+      prob = taken_edge->probability;
+    }
+
+  /* Now rescale the probabilities.  */
+  taken_edge->probability -= prob;
+  prob = REG_BR_PROB_BASE - prob;
+  bb->frequency -= edge_frequency;
+  if (bb->frequency < 0)
+    bb->frequency = 0;
+  if (prob <= 0)
+    {
+      if (dump_file)
+	fprintf (dump_file, "Edge frequencies of bb %i has been reset, "
+		 "frequency of block should end up being 0, it is %i\n",
+		 bb->index, bb->frequency);
+      EDGE_SUCC (bb, 0)->probability = REG_BR_PROB_BASE;
+      ei = ei_start (bb->succs);
+      ei_next (&ei);
+      for (; (c = ei_safe_edge (ei)); ei_next (&ei))
+	c->probability = 0;
+    }
+  else if (prob != REG_BR_PROB_BASE)
+    {
+      int scale = RDIV (65536 * REG_BR_PROB_BASE, prob);
+
+      FOR_EACH_EDGE (c, ei, bb->succs)
+	{
+	  /* Protect from overflow due to additional scaling.  */
+	  if (c->probability > prob)
+	    c->probability = REG_BR_PROB_BASE;
+	  else
+	    {
+	      c->probability = RDIV (c->probability * scale, 65536);
+	      if (c->probability > REG_BR_PROB_BASE)
+		c->probability = REG_BR_PROB_BASE;
+	    }
+	}
+    }
+
+  gcc_assert (bb == taken_edge->src);
+  taken_edge->count -= count;
+  if (taken_edge->count < 0)
+    {
+      if (dump_file)
+	fprintf (dump_file, "edge %i->%i count became negative after threading",
+		 taken_edge->src->index, taken_edge->dest->index);
+      taken_edge->count = 0;
+    }
+}
+
+/* Multiply all frequencies of basic blocks in array BBS of length NBBS
+   by NUM/DEN, in int arithmetic.  May lose some accuracy.  */
+void
+scale_bbs_frequencies_int (basic_block *bbs, int nbbs, int num, int den)
+{
+  int i;
+  edge e;
+  if (num < 0)
+    num = 0;
+
+  /* Scale NUM and DEN to avoid overflows.  Frequencies are in order of
+     10^4, if we make DEN <= 10^3, we can afford to upscale by 100
+     and still safely fit in int during calculations.  */
+  if (den > 1000)
+    {
+      if (num > 1000000)
+	return;
+
+      num = RDIV (1000 * num, den);
+      den = 1000;
+    }
+  if (num > 100 * den)
+    return;
+
+  for (i = 0; i < nbbs; i++)
+    {
+      edge_iterator ei;
+      bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
+      /* Make sure the frequencies do not grow over BB_FREQ_MAX.  */
+      if (bbs[i]->frequency > BB_FREQ_MAX)
+	bbs[i]->frequency = BB_FREQ_MAX;
+      bbs[i]->count = RDIV (bbs[i]->count * num, den);
+      FOR_EACH_EDGE (e, ei, bbs[i]->succs)
+	e->count = RDIV (e->count * num, den);
+    }
+}
+
+/* numbers smaller than this value are safe to multiply without getting
+   64bit overflow.  */
+#define MAX_SAFE_MULTIPLIER (1 << (sizeof (HOST_WIDEST_INT) * 4 - 1))
+
+/* Multiply all frequencies of basic blocks in array BBS of length NBBS
+   by NUM/DEN, in gcov_type arithmetic.  More accurate than previous
+   function but considerably slower.  */
+void
+scale_bbs_frequencies_gcov_type (basic_block *bbs, int nbbs, gcov_type num,
+				 gcov_type den)
+{
+  int i;
+  edge e;
+  gcov_type fraction = RDIV (num * 65536, den);
+
+  gcc_assert (fraction >= 0);
+
+  if (num < MAX_SAFE_MULTIPLIER)
+    for (i = 0; i < nbbs; i++)
+      {
+	edge_iterator ei;
+	bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
+	if (bbs[i]->count <= MAX_SAFE_MULTIPLIER)
+	  bbs[i]->count = RDIV (bbs[i]->count * num, den);
+	else
+	  bbs[i]->count = RDIV (bbs[i]->count * fraction, 65536);
+	FOR_EACH_EDGE (e, ei, bbs[i]->succs)
+	  if (bbs[i]->count <= MAX_SAFE_MULTIPLIER)
+	    e->count = RDIV (e->count * num, den);
+	  else
+	    e->count = RDIV (e->count * fraction, 65536);
+      }
+   else
+    for (i = 0; i < nbbs; i++)
+      {
+	edge_iterator ei;
+	if (sizeof (gcov_type) > sizeof (int))
+	  bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
+	else
+	  bbs[i]->frequency = RDIV (bbs[i]->frequency * fraction, 65536);
+	bbs[i]->count = RDIV (bbs[i]->count * fraction, 65536);
+	FOR_EACH_EDGE (e, ei, bbs[i]->succs)
+	  e->count = RDIV (e->count * fraction, 65536);
+      }
+}
+
+/* Data structures used to maintain mapping between basic blocks and
+   copies.  */
+static htab_t bb_original;
+static htab_t bb_copy;
+
+/* And between loops and copies.  */
+static htab_t loop_copy;
+static alloc_pool original_copy_bb_pool;
+
+struct htab_bb_copy_original_entry
+{
+  /* Block we are attaching info to.  */
+  int index1;
+  /* Index of original or copy (depending on the hashtable) */
+  int index2;
+};
+
+static hashval_t
+bb_copy_original_hash (const void *p)
+{
+  const struct htab_bb_copy_original_entry *data
+    = ((const struct htab_bb_copy_original_entry *)p);
+
+  return data->index1;
+}
+static int
+bb_copy_original_eq (const void *p, const void *q)
+{
+  const struct htab_bb_copy_original_entry *data
+    = ((const struct htab_bb_copy_original_entry *)p);
+  const struct htab_bb_copy_original_entry *data2
+    = ((const struct htab_bb_copy_original_entry *)q);
+
+  return data->index1 == data2->index1;
+}
+
+/* Initialize the data structures to maintain mapping between blocks
+   and its copies.  */
+void
+initialize_original_copy_tables (void)
+{
+  gcc_assert (!original_copy_bb_pool);
+  original_copy_bb_pool
+    = create_alloc_pool ("original_copy",
+			 sizeof (struct htab_bb_copy_original_entry), 10);
+  bb_original = htab_create (10, bb_copy_original_hash,
+			     bb_copy_original_eq, NULL);
+  bb_copy = htab_create (10, bb_copy_original_hash, bb_copy_original_eq, NULL);
+  loop_copy = htab_create (10, bb_copy_original_hash, bb_copy_original_eq, NULL);
+}
+
+/* Free the data structures to maintain mapping between blocks and
+   its copies.  */
+void
+free_original_copy_tables (void)
+{
+  gcc_assert (original_copy_bb_pool);
+  htab_delete (bb_copy);
+  htab_delete (bb_original);
+  htab_delete (loop_copy);
+  free_alloc_pool (original_copy_bb_pool);
+  bb_copy = NULL;
+  bb_original = NULL;
+  loop_copy = NULL;
+  original_copy_bb_pool = NULL;
+}
+
+/* Removes the value associated with OBJ from table TAB.  */
+
+static void
+copy_original_table_clear (htab_t tab, unsigned obj)
+{
+  void **slot;
+  struct htab_bb_copy_original_entry key, *elt;
+
+  if (!original_copy_bb_pool)
+    return;
+
+  key.index1 = obj;
+  slot = htab_find_slot (tab, &key, NO_INSERT);
+  if (!slot)
+    return;
+
+  elt = (struct htab_bb_copy_original_entry *) *slot;
+  htab_clear_slot (tab, slot);
+  pool_free (original_copy_bb_pool, elt);
+}
+
+/* Sets the value associated with OBJ in table TAB to VAL.
+   Do nothing when data structures are not initialized.  */
+
+static void
+copy_original_table_set (htab_t tab, unsigned obj, unsigned val)
+{
+  struct htab_bb_copy_original_entry **slot;
+  struct htab_bb_copy_original_entry key;
+
+  if (!original_copy_bb_pool)
+    return;
+
+  key.index1 = obj;
+  slot = (struct htab_bb_copy_original_entry **)
+		htab_find_slot (tab, &key, INSERT);
+  if (!*slot)
+    {
+      *slot = (struct htab_bb_copy_original_entry *)
+		pool_alloc (original_copy_bb_pool);
+      (*slot)->index1 = obj;
+    }
+  (*slot)->index2 = val;
+}
+
+/* Set original for basic block.  Do nothing when data structures are not
+   initialized so passes not needing this don't need to care.  */
+void
+set_bb_original (basic_block bb, basic_block original)
+{
+  copy_original_table_set (bb_original, bb->index, original->index);
+}
+
+/* Get the original basic block.  */
+basic_block
+get_bb_original (basic_block bb)
+{
+  struct htab_bb_copy_original_entry *entry;
+  struct htab_bb_copy_original_entry key;
+
+  gcc_assert (original_copy_bb_pool);
+
+  key.index1 = bb->index;
+  entry = (struct htab_bb_copy_original_entry *) htab_find (bb_original, &key);
+  if (entry)
+    return BASIC_BLOCK (entry->index2);
+  else
+    return NULL;
+}
+
+/* Set copy for basic block.  Do nothing when data structures are not
+   initialized so passes not needing this don't need to care.  */
+void
+set_bb_copy (basic_block bb, basic_block copy)
+{
+  copy_original_table_set (bb_copy, bb->index, copy->index);
+}
+
+/* Get the copy of basic block.  */
+basic_block
+get_bb_copy (basic_block bb)
+{
+  struct htab_bb_copy_original_entry *entry;
+  struct htab_bb_copy_original_entry key;
+
+  gcc_assert (original_copy_bb_pool);
+
+  key.index1 = bb->index;
+  entry = (struct htab_bb_copy_original_entry *) htab_find (bb_copy, &key);
+  if (entry)
+    return BASIC_BLOCK (entry->index2);
+  else
+    return NULL;
+}
+
+/* Set copy for LOOP to COPY.  Do nothing when data structures are not
+   initialized so passes not needing this don't need to care.  */
+
+void
+set_loop_copy (struct loop *loop, struct loop *copy)
+{
+  if (!copy)
+    copy_original_table_clear (loop_copy, loop->num);
+  else
+    copy_original_table_set (loop_copy, loop->num, copy->num);
+}
+
+/* Get the copy of LOOP.  */
+
+struct loop *
+get_loop_copy (struct loop *loop)
+{
+  struct htab_bb_copy_original_entry *entry;
+  struct htab_bb_copy_original_entry key;
+
+  gcc_assert (original_copy_bb_pool);
+
+  key.index1 = loop->num;
+  entry = (struct htab_bb_copy_original_entry *) htab_find (loop_copy, &key);
+  if (entry)
+    return get_loop (entry->index2);
+  else
+    return NULL;
+}