cfganal.c (flow_reverse_top_sort_order_compute): Renamed to post_order_compute and additional parameter added which allows the...

2005-12-20  Kenneth Zadeck <zadeck@naturalbridge.com>

	* cfganal.c (flow_reverse_top_sort_order_compute):
	Renamed to post_order_compute and additional parameter added which
	allows the inclusion of entry and exit blocks into list.
	(mark_dfs_back_edges): Fixed comment.
	(flow_depth_first_order_compute): Renamed to
	pre_and_rev_post_order_compute additional parameter added which
	allows the inclusion of entry and exit blocks into list.
	* global.c (set_up_bb_rts_numbers): Call to
	flow_reverse_top_sort_order_compute renamed to
	post_order_compute.
	* var-tracking.c (vt_stack_adjustments): Fixed comment.
	(vt_find_locations): Call to
	flow_depth_first_order_compute renamed to
	pre_and_rev_post_order_compute.
	* cfgloop.c (flow_find_loops): Ditto.
	* tree-ssa-reassoc.c (init_reassoc): Ditto.
	* df.c (df_analyze_1, df_analyze_subcfg): Calls to
	flow_reverse_top_sort_order_compute renamed to post_order_compute
	and calls to flow_reverse_top_sort_order_compute renamed to
	post_order_compute.
	* basic_block.h: Ditto.

From-SVN: r108874

gcc/ChangeLog

@@ -1,3 +1,28 @@
+2005-12-20  Kenneth Zadeck <zadeck@naturalbridge.com>
+
+	* cfganal.c (flow_reverse_top_sort_order_compute):
+	Renamed to post_order_compute and additional parameter added which
+	allows the inclusion of entry and exit blocks into list.
+	(mark_dfs_back_edges): Fixed comment.
+	(flow_depth_first_order_compute): Renamed to
+	pre_and_rev_post_order_compute additional parameter added which
+	allows the inclusion of entry and exit blocks into list.
+	* global.c (set_up_bb_rts_numbers): Call to
+	flow_reverse_top_sort_order_compute renamed to
+	post_order_compute.
+	* var-tracking.c (vt_stack_adjustments): Fixed comment.
+	(vt_find_locations): Call to
+	flow_depth_first_order_compute renamed to
+	pre_and_rev_post_order_compute.
+	* cfgloop.c (flow_find_loops): Ditto.
+	* tree-ssa-reassoc.c (init_reassoc): Ditto.
+	* df.c (df_analyze_1, df_analyze_subcfg): Calls to
+	flow_reverse_top_sort_order_compute renamed to post_order_compute
+	and calls to flow_reverse_top_sort_order_compute renamed to
+	post_order_compute.
+	* basic_block.h: Ditto.
+
+
 2005-12-20  Roger Sayle  <roger@eyesopen.com>
 	    Paolo Bonzini  <bonzini@gnu.org>
 

gcc/basic-block.h

@@ -503,8 +503,8 @@ extern edge redirect_edge_succ_nodup (edge, basic_block);
 extern void redirect_edge_pred (edge, basic_block);
 extern basic_block create_basic_block_structure (rtx, rtx, rtx, basic_block);
 extern void clear_bb_flags (void);
-extern void flow_reverse_top_sort_order_compute (int *);
-extern int flow_depth_first_order_compute (int *, int *);
+extern int post_order_compute (int *, bool);
+extern int pre_and_rev_post_order_compute (int *, int *, bool);
 extern int dfs_enumerate_from (basic_block, int,
 			       bool (*)(basic_block, void *),
 			       basic_block *, int, void *);

gcc/cfganal.c

@@ -152,7 +152,7 @@ could_fall_through (basic_block src, basic_block target)
      Steven Muchnick
      Morgan Kaufmann, 1997
 
-   and heavily borrowed from flow_depth_first_order_compute.  */
+   and heavily borrowed from pre_and_rev_post_order_compute.  */
 
 bool
 mark_dfs_back_edges (void)
@@ -645,16 +645,20 @@ connect_infinite_loops_to_exit (void)
   return;
 }
 
-/* Compute reverse top sort order.  */
+/* Compute reverse top sort order.  
+   This is computing a post order numbering of the graph.  */
 
-void
-flow_reverse_top_sort_order_compute (int *rts_order)
+int
+post_order_compute (int *post_order, bool include_entry_exit)
 {
   edge_iterator *stack;
   int sp;
-  int postnum = 0;
+  int post_order_num = 0;
   sbitmap visited;
 
+  if (include_entry_exit)
+    post_order[post_order_num++] = EXIT_BLOCK;
+
   /* Allocate stack for back-tracking up CFG.  */
   stack = xmalloc ((n_basic_blocks + 1) * sizeof (edge_iterator));
   sp = 0;
@@ -690,12 +694,12 @@ flow_reverse_top_sort_order_compute (int *rts_order)
 	       time, check its successors.  */
 	    stack[sp++] = ei_start (dest->succs);
 	  else
-	    rts_order[postnum++] = dest->index;
+	    post_order[post_order_num++] = dest->index;
 	}
       else
 	{
 	  if (ei_one_before_end_p (ei) && src != ENTRY_BLOCK_PTR)
-	   rts_order[postnum++] = src->index;
+	   post_order[post_order_num++] = src->index;
 
 	  if (!ei_one_before_end_p (ei))
 	    ei_next (&stack[sp - 1]);
@@ -704,30 +708,50 @@ flow_reverse_top_sort_order_compute (int *rts_order)
 	}
     }
 
+  if (include_entry_exit)
+    post_order[post_order_num++] = ENTRY_BLOCK;
+
   free (stack);
   sbitmap_free (visited);
+  return post_order_num;
 }
 
 /* Compute the depth first search order and store in the array
-  DFS_ORDER if nonzero, marking the nodes visited in VISITED.  If
-  RC_ORDER is nonzero, return the reverse completion number for each
+  PRE_ORDER if nonzero, marking the nodes visited in VISITED.  If
+  REV_POST_ORDER is nonzero, return the reverse completion number for each
   node.  Returns the number of nodes visited.  A depth first search
   tries to get as far away from the starting point as quickly as
-  possible.  */
+  possible. 
+
+  pre_order is a really a preorder numbering of the graph.
+  rev_post_order is really a reverse postorder numbering of the graph.
+ */
 
 int
-flow_depth_first_order_compute (int *dfs_order, int *rc_order)
+pre_and_rev_post_order_compute (int *pre_order, int *rev_post_order, 
+				bool include_entry_exit)
 {
   edge_iterator *stack;
   int sp;
-  int dfsnum = 0;
-  int rcnum = n_basic_blocks - 1 - NUM_FIXED_BLOCKS;
+  int pre_order_num = 0;
+  int rev_post_order_num = n_basic_blocks - 1;
   sbitmap visited;
 
   /* Allocate stack for back-tracking up CFG.  */
   stack = xmalloc ((n_basic_blocks + 1) * sizeof (edge_iterator));
   sp = 0;
 
+  if (include_entry_exit)
+    {
+      if (pre_order)
+	pre_order[pre_order_num] = ENTRY_BLOCK;
+      pre_order_num++;
+      if (rev_post_order)
+	rev_post_order[rev_post_order_num--] = ENTRY_BLOCK;
+    }
+  else 
+    rev_post_order_num -= NUM_FIXED_BLOCKS;
+
   /* Allocate bitmap to track nodes that have been visited.  */
   visited = sbitmap_alloc (last_basic_block);
 
@@ -754,27 +778,27 @@ flow_depth_first_order_compute (int *dfs_order, int *rc_order)
 	  /* Mark that we have visited the destination.  */
 	  SET_BIT (visited, dest->index);
 
-	  if (dfs_order)
-	    dfs_order[dfsnum] = dest->index;
+	  if (pre_order)
+	    pre_order[pre_order_num] = dest->index;
 
-	  dfsnum++;
+	  pre_order_num++;
 
 	  if (EDGE_COUNT (dest->succs) > 0)
 	    /* Since the DEST node has been visited for the first
 	       time, check its successors.  */
 	    stack[sp++] = ei_start (dest->succs);
-	  else if (rc_order)
+	  else if (rev_post_order)
 	    /* There are no successors for the DEST node so assign
 	       its reverse completion number.  */
-	    rc_order[rcnum--] = dest->index;
+	    rev_post_order[rev_post_order_num--] = dest->index;
 	}
       else
 	{
 	  if (ei_one_before_end_p (ei) && src != ENTRY_BLOCK_PTR
-	      && rc_order)
+	      && rev_post_order)
 	    /* There are no more successors for the SRC node
 	       so assign its reverse completion number.  */
-	    rc_order[rcnum--] = src->index;
+	    rev_post_order[rev_post_order_num--] = src->index;
 
 	  if (!ei_one_before_end_p (ei))
 	    ei_next (&stack[sp - 1]);
@@ -786,11 +810,22 @@ flow_depth_first_order_compute (int *dfs_order, int *rc_order)
   free (stack);
   sbitmap_free (visited);
 
-  /* The number of nodes visited should be the number of blocks minus
-     the entry and exit blocks which are not visited here.  */
-  gcc_assert (dfsnum == n_basic_blocks - NUM_FIXED_BLOCKS);
+  if (include_entry_exit)
+    {
+      if (pre_order)
+	pre_order[pre_order_num] = EXIT_BLOCK;
+      pre_order_num++;
+      if (rev_post_order)
+	rev_post_order[rev_post_order_num--] = EXIT_BLOCK;
+      /* The number of nodes visited should be the number of blocks.  */
+      gcc_assert (pre_order_num == n_basic_blocks);
+    }
+  else
+    /* The number of nodes visited should be the number of blocks minus
+       the entry and exit blocks which are not visited here.  */
+    gcc_assert (pre_order_num == n_basic_blocks - NUM_FIXED_BLOCKS);
 
-  return dfsnum;
+  return pre_order_num;
 }
 
 /* Compute the depth first search order on the _reverse_ graph and

gcc/cfgloop.c

@@ -696,7 +696,7 @@ flow_loops_find (struct loops *loops)
 	 natural loops will be found before inner natural loops.  */
       dfs_order = xmalloc (n_basic_blocks * sizeof (int));
       rc_order = xmalloc (n_basic_blocks * sizeof (int));
-      flow_depth_first_order_compute (dfs_order, rc_order);
+      pre_and_rev_post_order_compute (dfs_order, rc_order, false);
 
       /* Save CFG derived information to avoid recomputing it.  */
       loops->cfg.dfs_order = dfs_order;

gcc/df.c

@@ -1996,8 +1996,8 @@ df_analyze_1 (struct df *df, bitmap blocks, int flags, int update)
   df->rc_order = xmalloc (sizeof (int) * n_basic_blocks - NUM_FIXED_BLOCKS);
   df->rts_order = xmalloc (sizeof (int) * n_basic_blocks - NUM_FIXED_BLOCKS);
 
-  flow_depth_first_order_compute (df->dfs_order, df->rc_order);
-  flow_reverse_top_sort_order_compute (df->rts_order);
+  pre_and_rev_post_order_compute (df->dfs_order, df->rc_order, false);
+  post_order_compute (df->rts_order, false);
   if (aflags & DF_RD)
     {
       /* Compute the sets of gens and kills for the defs of each bb.  */
@@ -2424,8 +2424,8 @@ df_analyze_subcfg (struct df *df, bitmap blocks, int flags)
   df->rc_order = xmalloc (sizeof (int) * n_basic_blocks - NUM_FIXED_BLOCKS);
   df->rts_order = xmalloc (sizeof (int) * n_basic_blocks - NUM_FIXED_BLOCKS);
 
-  flow_depth_first_order_compute (df->dfs_order, df->rc_order);
-  flow_reverse_top_sort_order_compute (df->rts_order);
+  pre_and_rev_post_order_compute (df->dfs_order, df->rc_order, false);
+  post_order_compute (df->rts_order, false);
 
   n_blocks = prune_to_subcfg (df->dfs_order, n_basic_blocks - NUM_FIXED_BLOCKS, blocks);
   prune_to_subcfg (df->rc_order, n_basic_blocks - NUM_FIXED_BLOCKS, blocks);

gcc/global.c

@@ -2282,7 +2282,7 @@ set_up_bb_rts_numbers (void)
   int *rts_order;
   
   rts_order = xmalloc (sizeof (int) * (n_basic_blocks - NUM_FIXED_BLOCKS));
-  flow_reverse_top_sort_order_compute (rts_order);
+  post_order_compute (rts_order, false);
   for (i = 0; i < n_basic_blocks - NUM_FIXED_BLOCKS; i++)
     BB_INFO_BY_INDEX (rts_order [i])->rts_number = i;
   free (rts_order);

gcc/tree-ssa-reassoc.c

@@ -1424,7 +1424,7 @@ init_reassoc (void)
 
   /* Reverse RPO (Reverse Post Order) will give us something where
      deeper loops come later.  */
-  flow_depth_first_order_compute (NULL, bbs);
+  pre_and_rev_post_order_compute (NULL, bbs, false);
   bb_rank = xcalloc (last_basic_block + 1, sizeof (unsigned int));
   
   operand_rank = htab_create (511, operand_entry_hash,

gcc/var-tracking.c

@@ -485,7 +485,7 @@ bb_stack_adjust_offset (basic_block bb)
 
 /* Compute stack adjustments for all blocks by traversing DFS tree.
    Return true when the adjustments on all incoming edges are consistent.
-   Heavily borrowed from flow_depth_first_order_compute.  */
+   Heavily borrowed from pre_and_rev_post_order_compute.  */
 
 static bool
 vt_stack_adjustments (void)
@@ -1640,7 +1640,7 @@ vt_find_locations (void)
      so that the data-flow runs faster.  */
   rc_order = xmalloc ((n_basic_blocks - NUM_FIXED_BLOCKS) * sizeof (int));
   bb_order = xmalloc (last_basic_block * sizeof (int));
-  flow_depth_first_order_compute (NULL, rc_order);
+  pre_and_rev_post_order_compute (NULL, rc_order, false);
   for (i = 0; i < n_basic_blocks - NUM_FIXED_BLOCKS; i++)
     bb_order[rc_order[i]] = i;
   free (rc_order);