tree-ssa-structalias.c (new_var_info): Allocate oldsolution lazily.

2011-07-20  Richard Guenther  <rguenther@suse.de>

	* tree-ssa-structalias.c (new_var_info): Allocate oldsolution
	lazily.
	(unify_nodes): Deal with that.
	(solve_graph): Likewise.

From-SVN: r176505

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 605729cc946ed96482d6c4e356c329d8aa41f433..3ee9bfb7334f3ff40b2d2baf96139bf3465a21c0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2011-07-20  Richard Guenther  <rguenther@suse.de>
+
+       * tree-ssa-structalias.c (new_var_info): Allocate oldsolution
+       lazily.
+       (unify_nodes): Deal with that.
+       (solve_graph): Likewise.
+
 2011-07-20  Chung-Lin Tang  <cltang@codesourcery.com>
 
        * config/arm/arm.c (arm_canonicalize_comparison): Add case to

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 82f39c2fcada3918df400beeac013cec1637a7d3..9bfbad63f70dee07994c65211d1e08ca0940cf18 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -362,7 +362,7 @@ new_var_info (tree t, const char *name)
                          || (TREE_CODE (t) == VAR_DECL
                              && DECL_HARD_REGISTER (t)));
   ret->solution = BITMAP_ALLOC (&pta_obstack);
-  ret->oldsolution = BITMAP_ALLOC (&oldpta_obstack);
+  ret->oldsolution = NULL;
   ret->next = NULL;
 
   stats.total_vars++;
@@ -1504,13 +1504,12 @@ unify_nodes (constraint_graph_t graph, unsigned int to, unsigned int from,
        }
 
       BITMAP_FREE (get_varinfo (from)->solution);
-      BITMAP_FREE (get_varinfo (from)->oldsolution);
+      if (get_varinfo (from)->oldsolution)
+       BITMAP_FREE (get_varinfo (from)->oldsolution);
 
-      if (stats.iterations > 0)
-       {
-         BITMAP_FREE (get_varinfo (to)->oldsolution);
-         get_varinfo (to)->oldsolution = BITMAP_ALLOC (&oldpta_obstack);
-       }
+      if (stats.iterations > 0
+         && get_varinfo (to)->oldsolution)
+       BITMAP_FREE (get_varinfo (to)->oldsolution);
     }
   if (valid_graph_edge (graph, to, to))
     {
@@ -2544,18 +2543,27 @@ solve_graph (constraint_graph_t graph)
              constraint_t c;
              bitmap solution;
              VEC(constraint_t,heap) *complex = graph->complex[i];
+             varinfo_t vi = get_varinfo (i);
              bool solution_empty;
 
              /* Compute the changed set of solution bits.  */
-             bitmap_and_compl (pts, get_varinfo (i)->solution,
-                               get_varinfo (i)->oldsolution);
+             if (vi->oldsolution)
+               bitmap_and_compl (pts, vi->solution, vi->oldsolution);
+             else
+               bitmap_copy (pts, vi->solution);
 
              if (bitmap_empty_p (pts))
                continue;
 
-             bitmap_ior_into (get_varinfo (i)->oldsolution, pts);
+             if (vi->oldsolution)
+               bitmap_ior_into (vi->oldsolution, pts);
+             else
+               {
+                 vi->oldsolution = BITMAP_ALLOC (&oldpta_obstack);
+                 bitmap_copy (vi->oldsolution, pts);
+               }
 
-             solution = get_varinfo (i)->solution;
+             solution = vi->solution;
              solution_empty = bitmap_empty_p (solution);
 
              /* Process the complex constraints */