tree-vrp.c (update_value_range): Intersect the range with old recorded SSA name range...

2015-01-27  Richard Biener  <rguenther@suse.de>

	* tree-vrp.c (update_value_range): Intersect the range with
	old recorded SSA name range information.

From-SVN: r220164

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 213dfe94e0d25ba0fd2cec9209f2345618023222..a4efbafb852b0d0f0e57978a0da849417b64956b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-01-27  Richard Biener  <rguenther@suse.de>
+
+       * tree-vrp.c (update_value_range): Intersect the range with
+       old recorded SSA name range information.
+
 2015-01-27  Nick Clifton  <nickc@redhat.com>
 
        * config/rl78/rl78.c (rl78_expand_prologue): In G10 mode push the

diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index c5ca2876b57e223a99fdfc1a04acc3f7bab8b7c1..2bc22c6b57b271321ca8abb53290ca4459052958 100644 (file)
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -847,6 +847,23 @@ update_value_range (const_tree var, value_range_t *new_vr)
   value_range_t *old_vr;
   bool is_new;
 
+  /* If there is a value-range on the SSA name from earlier analysis
+     factor that in.  */
+  if (INTEGRAL_TYPE_P (TREE_TYPE (var)))
+    {
+      wide_int min, max;
+      value_range_type rtype = get_range_info (var, &min, &max);
+      if (rtype == VR_RANGE || rtype == VR_ANTI_RANGE)
+       {
+         value_range_d nr;
+         nr.type = rtype;
+         nr.min = wide_int_to_tree (TREE_TYPE (var), min);
+         nr.max = wide_int_to_tree (TREE_TYPE (var), max);
+         nr.equiv = NULL;
+         vrp_intersect_ranges (new_vr, &nr);
+       }
+    }
+
   /* Update the value range, if necessary.  */
   old_vr = get_value_range (var);
   is_new = old_vr->type != new_vr->type