re PR c/56113 (out of memory when compiling a function with many goto labels (50k...

2013-01-29  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/56113
	* tree-ssa-structalias.c (equiv_class_lookup): Also return
	the bitmap leader.
	(label_visit): Free duplicate bitmaps and record the leader instead.
	(perform_var_substitution): Adjust.

From-SVN: r195541

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4765ab792ce8a6334d154b5162c5a0d5cae71e09..c9273e4881adafadfb08b3f82d9550d814c5c4e2 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2013-01-29  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/56113
+       * tree-ssa-structalias.c (equiv_class_lookup): Also return
+       the bitmap leader.
+       (label_visit): Free duplicate bitmaps and record the leader instead.
+       (perform_var_substitution): Adjust.
+
 2013-01-29  Richard Biener  <rguenther@suse.de>
 
        PR tree-optimization/55270

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 4ad956f66491ebd80602e8d920e83bab04b2f1c6..cacfdab373254ec093b7e3b261b1c4a6bb4e8d52 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -1907,10 +1907,10 @@ equiv_class_label_eq (const void *p1, const void *p2)
 }
 
 /* Lookup a equivalence class in TABLE by the bitmap of LABELS it
-   contains.  */
+   contains.  Sets *REF_LABELS to the bitmap LABELS is equivalent to.  */
 
 static unsigned int
-equiv_class_lookup (htab_t table, bitmap labels)
+equiv_class_lookup (htab_t table, bitmap labels, bitmap *ref_labels)
 {
   void **slot;
   struct equiv_class_label ecl;
@@ -1921,9 +1921,18 @@ equiv_class_lookup (htab_t table, bitmap labels)
   slot = htab_find_slot_with_hash (table, &ecl,
                                   ecl.hashcode, NO_INSERT);
   if (!slot)
-    return 0;
+    {
+      if (ref_labels)
+       *ref_labels = NULL;
+      return 0;
+    }
   else
-    return ((equiv_class_label_t) *slot)->equivalence_class;
+    {
+      equiv_class_label_t ec = (equiv_class_label_t) *slot;
+      if (ref_labels)
+       *ref_labels = ec->labels;
+      return ec->equivalence_class;
+    }
 }
 
 
@@ -2123,14 +2132,21 @@ label_visit (constraint_graph_t graph, struct scc_info *si, unsigned int n)
 
   if (!bitmap_empty_p (graph->points_to[n]))
     {
+      bitmap ref_points_to;
       unsigned int label = equiv_class_lookup (pointer_equiv_class_table,
-                                              graph->points_to[n]);
+                                              graph->points_to[n],
+                                              &ref_points_to);
       if (!label)
        {
          label = pointer_equiv_class++;
          equiv_class_add (pointer_equiv_class_table,
                           label, graph->points_to[n]);
        }
+      else
+       {
+         BITMAP_FREE (graph->points_to[n]);
+         graph->points_to[n] = ref_points_to;
+       }
       graph->pointer_label[n] = label;
     }
 }
@@ -2190,7 +2206,7 @@ perform_var_substitution (constraint_graph_t graph)
       /* Look up the location equivalence label if one exists, or make
         one otherwise.  */
       label = equiv_class_lookup (location_equiv_class_table,
-                                 pointed_by);
+                                 pointed_by, NULL);
       if (label == 0)
        {
          label = location_equiv_class++;