X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fcfg.c;h=e842a5083467182e43898ddde9675404301b0cff;hb=631fa7dec48a8cd25753636d5990b8a131f01452;hp=6071e8dbedc159797d7671222ce222a787743e6c;hpb=35a3065a3eaa382dc4b1f9e0f8f4c41b81a2014d;p=pf3gnuchains%2Fgcc-fork.git

diff --git a/gcc/cfg.c b/gcc/cfg.c
index 6071e8dbedc..e842a508346 100644
--- a/gcc/cfg.c
+++ b/gcc/cfg.c
@@ -1,6 +1,7 @@
 /* Control flow graph manipulation code for GNU compiler.
    Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001 Free Software Foundation, Inc.
+   1999, 2000, 2001, 2002, 2003, 2004, 2005
+   Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -19,10 +20,11 @@ along with GCC; see the file COPYING.  If not, write to the Free
 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 02111-1307, USA.  */
 
-/* This file contains low level functions to manipulate with CFG and analyze it.
-   All other modules should not transform the datastructure directly and use
-   abstraction instead.  The file is supposed to be ordered bottom-up and should
-   not contain any code dependent on particular intermediate language (RTL or trees)
+/* 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
@@ -33,18 +35,24 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 	 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
-     - Dumpipng and debugging
+     - 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 "basic-block.h"
 #include "regs.h"
 #include "flags.h"
 #include "output.h"
@@ -53,279 +61,281 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #include "toplev.h"
 #include "tm_p.h"
 #include "obstack.h"
+#include "timevar.h"
+#include "ggc.h"
 
 /* The obstack on which the flow graph components are allocated.  */
 
-struct obstack flow_obstack;
-static char *flow_firstobj;
-
-/* Number of basic blocks in the current function.  */
-
-int n_basic_blocks;
-
-/* Number of edges in the current function.  */
-
-int n_edges;
-
-/* First edge in the deleted edges chain.  */
-
-edge first_deleted_edge;
-static basic_block first_deleted_block;
-
-/* The basic block array.  */
-
-varray_type basic_block_info;
-
-/* The special entry and exit blocks.  */
-
-struct basic_block_def entry_exit_blocks[2]
-= {{NULL,			/* head */
-    NULL,			/* end */
-    NULL,			/* head_tree */
-    NULL,			/* end_tree */
-    NULL,			/* pred */
-    NULL,			/* succ */
-    NULL,			/* local_set */
-    NULL,			/* cond_local_set */
-    NULL,			/* global_live_at_start */
-    NULL,			/* global_live_at_end */
-    NULL,			/* aux */
-    ENTRY_BLOCK,		/* index */
-    0,				/* loop_depth */
-    0,				/* count */
-    0,				/* frequency */
-    0				/* flags */
-  },
-  {
-    NULL,			/* head */
-    NULL,			/* end */
-    NULL,			/* head_tree */
-    NULL,			/* end_tree */
-    NULL,			/* pred */
-    NULL,			/* succ */
-    NULL,			/* local_set */
-    NULL,			/* cond_local_set */
-    NULL,			/* global_live_at_start */
-    NULL,			/* global_live_at_end */
-    NULL,			/* aux */
-    EXIT_BLOCK,			/* index */
-    0,				/* loop_depth */
-    0,				/* count */
-    0,				/* frequency */
-    0				/* flags */
-  }
-};
-
-void debug_flow_info			PARAMS ((void));
-static void free_edge			PARAMS ((edge));
+struct bitmap_obstack reg_obstack;
+
+void debug_flow_info (void);
+static void free_edge (edge);
 
-/* Called once at intialization time.  */
+#define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
+
+/* Called once at initialization time.  */
 
 void
-init_flow ()
+init_flow (void)
 {
-  static int initialized;
-
-  first_deleted_edge = 0;
-  first_deleted_block = 0;
+  if (!cfun->cfg)
+    cfun->cfg = ggc_alloc_cleared (sizeof (struct control_flow_graph));
   n_edges = 0;
-
-  if (!initialized)
-    {
-      gcc_obstack_init (&flow_obstack);
-      flow_firstobj = (char *) obstack_alloc (&flow_obstack, 0);
-      initialized = 1;
-    }
-  else
-    {
-      obstack_free (&flow_obstack, flow_firstobj);
-      flow_firstobj = (char *) obstack_alloc (&flow_obstack, 0);
-    }
+  ENTRY_BLOCK_PTR = ggc_alloc_cleared (sizeof (struct basic_block_def));
+  ENTRY_BLOCK_PTR->index = ENTRY_BLOCK;
+  EXIT_BLOCK_PTR = ggc_alloc_cleared (sizeof (struct basic_block_def));
+  EXIT_BLOCK_PTR->index = EXIT_BLOCK;
+  ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR;
+  EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR;
 }
 
 /* Helper function for remove_edge and clear_edges.  Frees edge structure
    without actually unlinking it from the pred/succ lists.  */
 
 static void
-free_edge (e)
-     edge e;
+free_edge (edge e ATTRIBUTE_UNUSED)
 {
   n_edges--;
-  memset (e, 0, sizeof (*e));
-  e->succ_next = first_deleted_edge;
-  first_deleted_edge = e;
+  ggc_free (e);
 }
 
 /* Free the memory associated with the edge structures.  */
 
 void
-clear_edges ()
+clear_edges (void)
 {
-  int i;
+  basic_block bb;
   edge e;
+  edge_iterator ei;
 
-  for (i = 0; i < n_basic_blocks; ++i)
+  FOR_EACH_BB (bb)
     {
-      basic_block bb = BASIC_BLOCK (i);
-      edge e = bb->succ;
-
-      while (e)
-	{
-	  edge next = e->succ_next;
-
-	  free_edge (e);
-	  e = next;
-	}
-      bb->succ = NULL;
-      bb->pred = NULL;
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	free_edge (e);
+      VEC_truncate (edge, bb->succs, 0);
+      VEC_truncate (edge, bb->preds, 0);
     }
 
-  e = ENTRY_BLOCK_PTR->succ;
-  while (e)
-    {
-      edge next = e->succ_next;
-
-      free_edge (e);
-      e = next;
-    }
-  EXIT_BLOCK_PTR->pred = NULL;
-  ENTRY_BLOCK_PTR->succ = NULL;
+  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);
 
-  if (n_edges)
-    abort ();
+  gcc_assert (!n_edges);
 }
 
 /* Allocate memory for basic_block.  */
 
 basic_block
-alloc_block ()
+alloc_block (void)
 {
   basic_block bb;
-
-  if (first_deleted_block)
-    {
-      bb = first_deleted_block;
-      first_deleted_block = (basic_block) bb->succ;
-      bb->succ = NULL;
-    }
-  else
-    {
-      bb = (basic_block) obstack_alloc (&flow_obstack, sizeof (*bb));
-      memset (bb, 0, sizeof (*bb));
-    }
+  bb = ggc_alloc_cleared (sizeof (*bb));
   return bb;
 }
 
-/* Remove block B from the basic block array and compact behind it.  */
+/* Initialize rbi (the structure containing data used by basic block
+   duplication and reordering) for the given basic block.  */
+
+void
+initialize_bb_rbi (basic_block bb)
+{
+  gcc_assert (!bb->rbi);
+  bb->rbi = ggc_alloc_cleared (sizeof (struct reorder_block_def));
+}
+
+/* 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
-expunge_block (b)
-     basic_block b;
+compact_blocks (void)
 {
-  int i, n = n_basic_blocks;
+  int i;
+  basic_block bb;
 
-  for (i = b->index; i + 1 < n; ++i)
+  i = 0;
+  FOR_EACH_BB (bb)
     {
-      basic_block x = BASIC_BLOCK (i + 1);
-      BASIC_BLOCK (i) = x;
-      x->index = i;
+      BASIC_BLOCK (i) = bb;
+      bb->index = i;
+      i++;
     }
 
-  /* Invalidate data to make bughunting easier.  */
-  memset (b, 0, sizeof (*b));
-  b->index = -3;
-  basic_block_info->num_elements--;
+  gcc_assert (i == n_basic_blocks);
+
+  for (; i < last_basic_block; i++)
+    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);
+  BASIC_BLOCK (b->index) = NULL;
   n_basic_blocks--;
-  b->succ = (edge) first_deleted_block;
-  first_deleted_block = (basic_block) b;
+  /* 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.  */
 }
 
-/* Create an edge connecting SRC and DST with FLAGS optionally using
-   edge cache CACHE.  Return the new edge, NULL if already exist.  */
+/* Connect E to E->src.  */
 
-edge
-cached_make_edge (edge_cache, src, dst, flags)
-     sbitmap *edge_cache;
-     basic_block src, dst;
-     int flags;
+static inline void
+connect_src (edge e)
 {
-  int use_edge_cache;
-  edge e;
+  VEC_safe_push (edge, gc, e->src->succs, e);
+}
 
-  /* Don't bother with edge cache for ENTRY or EXIT; there aren't that
-     many edges to them, and we didn't allocate memory for it.  */
-  use_edge_cache = (edge_cache
-		    && src != ENTRY_BLOCK_PTR
-		    && dst != EXIT_BLOCK_PTR);
+/* Connect E to E->dest.  */
 
-  /* Make sure we don't add duplicate edges.  */
-  switch (use_edge_cache)
-    {
-    default:
-      /* Quick test for non-existence of the edge.  */
-      if (! TEST_BIT (edge_cache[src->index], dst->index))
-	break;
-
-      /* The edge exists; early exit if no work to do.  */
-      if (flags == 0)
-	return NULL;
-
-      /* FALLTHRU */
-    case 0:
-      for (e = src->succ; e; e = e->succ_next)
-	if (e->dest == dst)
-	  {
-	    e->flags |= flags;
-	    return NULL;
-	  }
-      break;
-    }
+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;
+}
 
-  if (first_deleted_edge)
-    {
-      e = first_deleted_edge;
-      first_deleted_edge = e->succ_next;
-    }
-  else
+/* 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)); )
     {
-      e = (edge) obstack_alloc (&flow_obstack, sizeof (*e));
-      memset (e, 0, sizeof (*e));
+      if (tmp == e)
+	{
+	  VEC_unordered_remove (edge, src->succs, ei.index);
+	  return;
+	}
+      else
+	ei_next (&ei);
     }
+
+  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;
+}
+
+/* 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_alloc_cleared (sizeof (*e));
   n_edges++;
 
-  e->succ_next = src->succ;
-  e->pred_next = dst->pred;
   e->src = src;
   e->dest = dst;
   e->flags = flags;
 
-  src->succ = e;
-  dst->pred = e;
+  connect_src (e);
+  connect_dest (e);
 
-  if (use_edge_cache)
-    SET_BIT (edge_cache[src->index], dst->index);
+  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 (src, dest, flags)
-     basic_block src, dest;
-     int flags;
+make_edge (basic_block src, basic_block dest, int flags)
 {
-  return cached_make_edge (NULL, src, dest, 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 knowling
+/* 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 (src, dest, flags)
-     basic_block src, dest;
-     int flags;
+make_single_succ_edge (basic_block src, basic_block dest, int flags)
 {
   edge e = make_edge (src, dest, flags);
 
@@ -337,34 +347,13 @@ make_single_succ_edge (src, dest, flags)
 /* This function will remove an edge from the flow graph.  */
 
 void
-remove_edge (e)
-     edge e;
+remove_edge (edge e)
 {
-  edge last_pred = NULL;
-  edge last_succ = NULL;
-  edge tmp;
-  basic_block src, dest;
-  src = e->src;
-  dest = e->dest;
-  for (tmp = src->succ; tmp && tmp != e; tmp = tmp->succ_next)
-    last_succ = tmp;
-
-  if (!tmp)
-    abort ();
-  if (last_succ)
-    last_succ->succ_next = e->succ_next;
-  else
-    src->succ = e->succ_next;
+  remove_predictions_associated_with_edge (e);
+  execute_on_shrinking_pred (e);
 
-  for (tmp = dest->pred; tmp && tmp != e; tmp = tmp->pred_next)
-    last_pred = tmp;
-
-  if (!tmp)
-    abort ();
-  if (last_pred)
-    last_pred->pred_next = e->pred_next;
-  else
-    dest->pred = e->pred_next;
+  disconnect_src (e);
+  disconnect_dest (e);
 
   free_edge (e);
 }
@@ -372,157 +361,223 @@ remove_edge (e)
 /* Redirect an edge's successor from one block to another.  */
 
 void
-redirect_edge_succ (e, new_succ)
-     edge e;
-     basic_block new_succ;
+redirect_edge_succ (edge e, basic_block new_succ)
 {
-  edge *pe;
+  execute_on_shrinking_pred (e);
 
-  /* Disconnect the edge from the old successor block.  */
-  for (pe = &e->dest->pred; *pe != e; pe = &(*pe)->pred_next)
-    continue;
-  *pe = (*pe)->pred_next;
+  disconnect_dest (e);
 
-  /* Reconnect the edge to the new successor block.  */
-  e->pred_next = new_succ->pred;
-  new_succ->pred = 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 dupplicate edge.  */
+/* Like previous but avoid possible duplicate edge.  */
 
 edge
-redirect_edge_succ_nodup (e, new_succ)
-     edge e;
-     basic_block new_succ;
+redirect_edge_succ_nodup (edge e, basic_block new_succ)
 {
   edge s;
-  /* Check whether the edge is already present.  */
-  for (s = e->src->succ; s; s = s->succ_next)
-    if (s->dest == new_succ && s != e)
-      break;
-  if (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);
       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 (e, new_pred)
-     edge e;
-     basic_block new_pred;
+redirect_edge_pred (edge e, basic_block new_pred)
 {
-  edge *pe;
+  disconnect_src (e);
 
-  /* Disconnect the edge from the old predecessor block.  */
-  for (pe = &e->src->succ; *pe != e; pe = &(*pe)->succ_next)
-    continue;
-  *pe = (*pe)->succ_next;
+  e->src = new_pred;
 
   /* Reconnect the edge to the new predecessor block.  */
-  e->succ_next = new_pred->succ;
-  new_pred->succ = e;
-  e->src = new_pred;
+  connect_src (e);
+}
+
+/* Clear all basic block flags, with the exception of partitioning.  */
+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);
 }
 
+/* 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
-dump_flow_info (file)
-     FILE *file;
+check_bb_profile (basic_block bb, FILE * file)
 {
-  int i;
-  static const char * const reg_class_names[] = REG_CLASS_NAMES;
+  edge e;
+  int sum = 0;
+  gcov_type lsum;
+  edge_iterator ei;
 
-  fprintf (file, "%d registers.\n", max_regno);
-  for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
-    if (REG_N_REFS (i))
-      {
-	enum reg_class class, altclass;
-	fprintf (file, "\nRegister %d used %d times across %d insns",
-		 i, REG_N_REFS (i), REG_LIVE_LENGTH (i));
-	if (REG_BASIC_BLOCK (i) >= 0)
-	  fprintf (file, " in block %d", REG_BASIC_BLOCK (i));
-	if (REG_N_SETS (i))
-	  fprintf (file, "; set %d time%s", REG_N_SETS (i),
-		   (REG_N_SETS (i) == 1) ? "" : "s");
-	if (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 (PSEUDO_REGNO_BYTES (i) != UNITS_PER_WORD)
-	  fprintf (file, "; %d bytes", PSEUDO_REGNO_BYTES (i));
-	class = reg_preferred_class (i);
-	altclass = reg_alternate_class (i);
-	if (class != GENERAL_REGS || altclass != ALL_REGS)
+  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);
+    }
+}
+
+void
+dump_flow_info (FILE *file)
+{
+  basic_block bb;
+
+  /* There are no pseudo registers after reload.  Don't dump them.  */
+  if (reg_n_info && !reload_completed)
+    {
+      unsigned int i, max = max_reg_num ();
+      fprintf (file, "%d registers.\n", max);
+      for (i = FIRST_PSEUDO_REGISTER; i < max; i++)
+	if (REG_N_REFS (i))
 	  {
-	    if (altclass == ALL_REGS || class == ALL_REGS)
-	      fprintf (file, "; pref %s", reg_class_names[(int) class]);
-	    else if (altclass == NO_REGS)
-	      fprintf (file, "; %s or none", reg_class_names[(int) class]);
-	    else
-	      fprintf (file, "; pref %s, else %s",
-		       reg_class_names[(int) class],
-		       reg_class_names[(int) altclass]);
+	    enum reg_class class, altclass;
+
+	    fprintf (file, "\nRegister %d used %d times across %d insns",
+		     i, REG_N_REFS (i), REG_LIVE_LENGTH (i));
+	    if (REG_BASIC_BLOCK (i) >= 0)
+	      fprintf (file, " in block %d", REG_BASIC_BLOCK (i));
+	    if (REG_N_SETS (i))
+	      fprintf (file, "; set %d time%s", REG_N_SETS (i),
+		       (REG_N_SETS (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 (regno_reg_rtx[i] != NULL
+		&& PSEUDO_REGNO_BYTES (i) != UNITS_PER_WORD)
+	      fprintf (file, "; %d bytes", PSEUDO_REGNO_BYTES (i));
+
+	    class = reg_preferred_class (i);
+	    altclass = reg_alternate_class (i);
+	    if (class != GENERAL_REGS || altclass != ALL_REGS)
+	      {
+		if (altclass == ALL_REGS || class == ALL_REGS)
+		  fprintf (file, "; pref %s", reg_class_names[(int) class]);
+		else if (altclass == NO_REGS)
+		  fprintf (file, "; %s or none", reg_class_names[(int) class]);
+		else
+		  fprintf (file, "; pref %s, else %s",
+			   reg_class_names[(int) class],
+			   reg_class_names[(int) altclass]);
+	      }
+
+	    if (regno_reg_rtx[i] != NULL && REG_POINTER (regno_reg_rtx[i]))
+	      fprintf (file, "; pointer");
+	    fprintf (file, ".\n");
 	  }
-	if (REG_POINTER (regno_reg_rtx[i]))
-	  fprintf (file, "; pointer");
-	fprintf (file, ".\n");
-      }
+    }
 
   fprintf (file, "\n%d basic blocks, %d edges.\n", n_basic_blocks, n_edges);
-  for (i = 0; i < n_basic_blocks; i++)
+  FOR_EACH_BB (bb)
     {
-      basic_block bb = BASIC_BLOCK (i);
       edge e;
-
-      fprintf (file, "\nBasic block %d: first insn %d, last %d, loop_depth %d, count ",
-	       i, INSN_UID (bb->head), INSN_UID (bb->end), bb->loop_depth);
-      fprintf (file, HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) bb->count);
-      fprintf (file, ", freq %i.\n", bb->frequency);
+      edge_iterator ei;
+
+      fprintf (file, "\nBasic block %d ", bb->index);
+      fprintf (file, "prev %d, next %d, ",
+	       bb->prev_bb->index, 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);
+      if (maybe_hot_bb_p (bb))
+	fprintf (file, ", maybe hot");
+      if (probably_never_executed_bb_p (bb))
+	fprintf (file, ", probably never executed");
+      fprintf (file, ".\n");
 
       fprintf (file, "Predecessors: ");
-      for (e = bb->pred; e; e = e->pred_next)
+      FOR_EACH_EDGE (e, ei, bb->preds)
 	dump_edge_info (file, e, 0);
 
       fprintf (file, "\nSuccessors: ");
-      for (e = bb->succ; e; e = e->succ_next)
+      FOR_EACH_EDGE (e, ei, bb->succs)
 	dump_edge_info (file, e, 1);
 
-      fprintf (file, "\nRegisters live at start:");
-      dump_regset (bb->global_live_at_start, file);
+      if (bb->global_live_at_start)
+	{
+	  fprintf (file, "\nRegisters live at start:");
+	  dump_regset (bb->global_live_at_start, file);
+	}
 
-      fprintf (file, "\nRegisters live at end:");
-      dump_regset (bb->global_live_at_end, file);
+      if (bb->global_live_at_end)
+	{
+	  fprintf (file, "\nRegisters live at end:");
+	  dump_regset (bb->global_live_at_end, file);
+	}
 
       putc ('\n', file);
+      check_bb_profile (bb, file);
     }
 
   putc ('\n', file);
 }
 
 void
-debug_flow_info ()
+debug_flow_info (void)
 {
   dump_flow_info (stderr);
 }
 
 void
-dump_edge_info (file, e, do_succ)
-     FILE *file;
-     edge e;
-     int do_succ;
+dump_edge_info (FILE *file, edge e, int do_succ)
 {
   basic_block side = (do_succ ? e->dest : e->src);
 
@@ -539,19 +594,20 @@ dump_edge_info (file, e, do_succ)
   if (e->count)
     {
       fprintf (file, " count:");
-      fprintf (file, HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) e->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"
+	"fallthru", "ab", "abcall", "eh", "fake", "dfs_back",
+	"can_fallthru", "irreducible", "sibcall", "loop_exit",
+	"true", "false", "exec"
       };
       int comma = 0;
       int i, flags = e->flags;
 
-      fputc (' ', file);
-      fputc ('(', file);
+      fputs (" (", file);
       for (i = 0; flags; i++)
 	if (flags & (1 << i))
 	  {
@@ -565,27 +621,26 @@ dump_edge_info (file, e, do_succ)
 	      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 an memory block of SIZE as BB->aux.  The obstack must
+/* 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 (bb, size)
-     basic_block bb;
-     int size;
+alloc_aux_for_block (basic_block bb, int size)
 {
   /* Verify that aux field is clear.  */
-  if (bb->aux || !first_block_aux_obj)
-    abort ();
+  gcc_assert (!bb->aux && first_block_aux_obj);
   bb->aux = obstack_alloc (&block_aux_obstack, size);
   memset (bb->aux, 0, size);
 }
@@ -594,8 +649,7 @@ alloc_aux_for_block (bb, size)
    alloc_aux_for_block for each basic block.  */
 
 void
-alloc_aux_for_blocks (size)
-     int size;
+alloc_aux_for_blocks (int size)
 {
   static int initialized;
 
@@ -604,58 +658,52 @@ alloc_aux_for_blocks (size)
       gcc_obstack_init (&block_aux_obstack);
       initialized = 1;
     }
-  /* Check whether AUX data are still allocated.  */
-  else if (first_block_aux_obj)
-    abort ();
-  first_block_aux_obj = (char *) obstack_alloc (&block_aux_obstack, 0);
+  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)
     {
-      int i;
-      for (i = 0; i < n_basic_blocks; i++)
-	alloc_aux_for_block (BASIC_BLOCK (i), size);
-      alloc_aux_for_block (ENTRY_BLOCK_PTR, size);
-      alloc_aux_for_block (EXIT_BLOCK_PTR, 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 ()
+clear_aux_for_blocks (void)
 {
-  int i;
+  basic_block bb;
 
-  for (i = 0; i < n_basic_blocks; i++)
-    BASIC_BLOCK (i)->aux = NULL;
-  ENTRY_BLOCK_PTR->aux = NULL;
-  EXIT_BLOCK_PTR->aux = NULL;
+  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 ()
+free_aux_for_blocks (void)
 {
-  if (!first_block_aux_obj)
-    abort ();
+  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 an memory edge of SIZE as BB->aux.  The obstack must
+/* 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 (e, size)
-     edge e;
-     int size;
+alloc_aux_for_edge (edge e, int size)
 {
   /* Verify that aux field is clear.  */
-  if (e->aux || !first_edge_aux_obj)
-    abort ();
+  gcc_assert (!e->aux && first_edge_aux_obj);
   e->aux = obstack_alloc (&edge_aux_obstack, size);
   memset (e->aux, 0, size);
 }
@@ -664,8 +712,7 @@ alloc_aux_for_edge (e, size)
    alloc_aux_for_edge for each basic edge.  */
 
 void
-alloc_aux_for_edges (size)
-     int size;
+alloc_aux_for_edges (int size)
 {
   static int initialized;
 
@@ -674,23 +721,21 @@ alloc_aux_for_edges (size)
       gcc_obstack_init (&edge_aux_obstack);
       initialized = 1;
     }
-  /* Check whether AUX data are still allocated.  */
-  else if (first_edge_aux_obj)
-    abort ();
-  first_edge_aux_obj = (char *) obstack_alloc (&edge_aux_obstack, 0);
+  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)
     {
-      int i;
-      for (i = -1; i < n_basic_blocks; i++)
+      basic_block bb;
+
+      FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
 	{
-	  basic_block bb;
 	  edge e;
+	  edge_iterator ei;
 
-	  if (i >= 0)
-	    bb = BASIC_BLOCK (i);
-	  else
-	    bb = ENTRY_BLOCK_PTR;
-	  for (e = bb->succ; e; e = e->succ_next)
+	  FOR_EACH_EDGE (e, ei, bb->succs)
 	    alloc_aux_for_edge (e, size);
 	}
     }
@@ -699,20 +744,15 @@ alloc_aux_for_edges (size)
 /* Clear AUX pointers of all edges.  */
 
 void
-clear_aux_for_edges ()
+clear_aux_for_edges (void)
 {
-  int i;
+  basic_block bb;
+  edge e;
 
-  for (i = -1; i < n_basic_blocks; i++)
+  FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
     {
-      basic_block bb;
-      edge e;
-
-      if (i >= 0)
-	bb = BASIC_BLOCK (i);
-      else
-	bb = ENTRY_BLOCK_PTR;
-      for (e = bb->succ; e; e = e->succ_next)
+      edge_iterator ei;
+      FOR_EACH_EDGE (e, ei, bb->succs)
 	e->aux = NULL;
     }
 }
@@ -721,12 +761,182 @@ clear_aux_for_edges ()
    of all edges.  */
 
 void
-free_aux_for_edges ()
+free_aux_for_edges (void)
 {
-  if (!first_edge_aux_obj)
-    abort ();
+  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[] =
+    {
+      "dirty", "new", "reachable", "visited", "irreducible_loop", "superblock"
+    };
+  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)
+    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 = 65536 * REG_BR_PROB_BASE / prob;
+
+      FOR_EACH_EDGE (c, ei, bb->succs)
+	c->probability *= scale / 65536;
+    }
+
+  gcc_assert (bb == taken_edge->src);
+  taken_edge->count -= count;
+  if (taken_edge->count < 0)
+    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;
+  for (i = 0; i < nbbs; i++)
+    {
+      edge_iterator ei;
+      bbs[i]->frequency = (bbs[i]->frequency * num) / den;
+      bbs[i]->count = RDIV (bbs[i]->count * num, den);
+      FOR_EACH_EDGE (e, ei, bbs[i]->succs)
+	e->count = (e->count * num) /den;
+    }
+}
+
+/* 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;
+
+  for (i = 0; i < nbbs; i++)
+    {
+      edge_iterator ei;
+      bbs[i]->frequency = (bbs[i]->frequency * num) / den;
+      bbs[i]->count = RDIV (bbs[i]->count * num, den);
+      FOR_EACH_EDGE (e, ei, bbs[i]->succs)
+	e->count = (e->count * num) /den;
+    }
+}