Switch live on entry to a per block basis from per variable.

	* tree-outof-ssa.c (coalesce_ssa_name): Use calculate_live_ranges.
	* tree-ssa-live.c (new_tree_live_info, delete_tree_live_info): Update.
	(add_livein_if_notdef): Delete.
	(loe_visit_block): New.  Propogate live on entry info for a block into
	each predecessor.  If it changes, make sure it is visited again.
	(live_worklist): Visit every block and update the live on entry info 
	for preds.  Iterate over any that changed.
	(set_var_live_on_entry): Populate the live on entry blocks with bits
	based on the immediate uses of a var.
	(calculate_live_on_entry): Remove.
	(calculate_live_on_exit): Calculate live on exit based on the newly
	oriented live on entry bits.
	(calculate_live_ranges): Build live on entry and exit vectors.
	(dump_live_info): Use new orientation of live on entry bitmaps.
	(verify_live_on_entry): New.  Split out verification code from old
	calculate_live_on_entry routine.
	* tree-ssa-live.h (struct tree_live_info_d): Add Working stack.
	(live_entry_blocks): Rename to live_on_entry and return bitmap for a
	basic_block instead of for a partition.
	(live_merge_and_clear): Add asserts.
	(make_live_on_entry): Set partition bit in basic block vector.

From-SVN: r119495

gcc/ChangeLog

+2006-12-04  Andrew MacLeod  <amacleod@redhat.com>
+
+	* tree-outof-ssa.c (coalesce_ssa_name): Use calculate_live_ranges.
+	* tree-ssa-live.c (new_tree_live_info, delete_tree_live_info): Update.
+	(add_livein_if_notdef): Delete.
+	(loe_visit_block): New.  Propogate live on entry info for a block into
+	each predecessor.  If it changes, make sure it is visited again.
+	(live_worklist): Visit every block and update the live on entry info 
+	for preds.  Iterate over any that changed.
+	(set_var_live_on_entry): Populate the live on entry blocks with bits
+	based on the immediate uses of a var.
+	(calculate_live_on_entry): Remove.
+	(calculate_live_on_exit): Calculate live on exit based on the newly
+	oriented live on entry bits.
+	(calculate_live_ranges): Build live on entry and exit vectors.
+	(dump_live_info): Use new orientation of live on entry bitmaps.
+	(verify_live_on_entry): New.  Split out verification code from old
+	calculate_live_on_entry routine.
+	* tree-ssa-live.h (struct tree_live_info_d): Add Working stack.
+	(live_entry_blocks): Rename to live_on_entry and return bitmap for a
+	basic_block instead of for a partition.
+	(live_merge_and_clear): Add asserts.
+	(make_live_on_entry): Set partition bit in basic block vector.
+
 2006-12-04  Jakub Jelinek  <jakub@redhat.com>
 
 	PR libgomp/29947

gcc/tree-outof-ssa.c

@@ -822,8 +822,7 @@ coalesce_ssa_name (var_map map, int flags)
   if (num_var_partitions (map) <= 1)
     return NULL;
 
-  liveinfo = calculate_live_on_entry (map);
-  calculate_live_on_exit (liveinfo);
+  liveinfo = calculate_live_ranges (map);
   rv = root_var_init (map);
 
   /* Remove single element variable from the list.  */

gcc/tree-ssa-live.h

@@ -182,11 +182,11 @@ register_ssa_partition (var_map map, tree ssa_var)
     As well, partitions are marked as to whether they are global (live 
     outside the basic block they are defined in).
 
-    The live-on-entry information is per variable. It provide a bitmap for 
-    each variable which has a bit set for each basic block that the variable
-    is live on entry to that block.
+    The live-on-entry information is per block.  It provide a bitmap for 
+    each block which has a bit set for each partition that is live on entry to 
+    that block.
 
-    The live-on-exit information is per block. It provides a bitmap for each
+    The live-on-exit information is per block.  It provides a bitmap for each
     block indicating which partitions are live on exit from the block.
 
     For the purposes of this implementation, we treat the elements of a PHI 
@@ -218,12 +218,18 @@ typedef struct tree_live_info_d
   /* Number of basic blocks when live on exit calculated.  */
   int num_blocks;
 
+  /* Vector used when creating live ranges as a visited stack.  */
+  int *work_stack;
+
+  /* Top of workstack.  */
+  int *stack_top;
+
   /* Bitmap of what variables are live on exit for a basic blocks.  */
   bitmap *liveout;
 } *tree_live_info_p;
 
 
-extern tree_live_info_p calculate_live_on_entry (var_map);
+extern tree_live_info_p calculate_live_ranges (var_map);
 extern void calculate_live_on_exit (tree_live_info_p);
 extern void delete_tree_live_info (tree_live_info_p);
 
@@ -233,7 +239,7 @@ extern void delete_tree_live_info (tree_live_info_p);
 extern void dump_live_info (FILE *, tree_live_info_p, int);
 
 static inline int partition_is_global (tree_live_info_p, int);
-static inline bitmap live_entry_blocks (tree_live_info_p, int);
+static inline bitmap live_on_entry (tree_live_info_p, basic_block);
 static inline bitmap live_on_exit (tree_live_info_p, basic_block);
 static inline var_map live_var_map (tree_live_info_p);
 static inline void live_merge_and_clear (tree_live_info_p, int, int);
@@ -254,10 +260,13 @@ partition_is_global (tree_live_info_p live, int p)
    partition P.  */
 
 static inline bitmap
-live_entry_blocks (tree_live_info_p live, int p)
+live_on_entry (tree_live_info_p live, basic_block bb)
 {
   gcc_assert (live->livein);
-  return live->livein[p];
+  gcc_assert (bb != ENTRY_BLOCK_PTR);
+  gcc_assert (bb != EXIT_BLOCK_PTR);
+
+  return live->livein[bb->index];
 }
 
 
@@ -290,6 +299,8 @@ live_var_map (tree_live_info_p live)
 static inline void 
 live_merge_and_clear (tree_live_info_p live, int p1, int p2)
 {
+  gcc_assert (live->livein[p1]);
+  gcc_assert (live->livein[p2]);
   bitmap_ior_into (live->livein[p1], live->livein[p2]);
   bitmap_zero (live->livein[p2]);
 }
@@ -300,7 +311,7 @@ live_merge_and_clear (tree_live_info_p live, int p1, int p2)
 static inline void 
 make_live_on_entry (tree_live_info_p live, basic_block bb , int p)
 {
-  bitmap_set_bit (live->livein[p], bb->index);
+  bitmap_set_bit (live->livein[bb->index], p);
   bitmap_set_bit (live->global, p);
 }