If the input to an HChange is of type smi, then no need to mark gvn flag changes...

BUG=

Review URL: https://codereview.chromium.org/14253010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14401 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 443dcc8..6ec6981 100644 (file)
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -1757,11 +1757,15 @@ class HChange: public HUnaryOperation {
     ASSERT(!value->representation().IsNone() && !to.IsNone());
     ASSERT(!value->representation().Equals(to));
     set_representation(to);
-    set_type(HType::TaggedNumber());
     SetFlag(kUseGVN);
     if (deoptimize_on_undefined) SetFlag(kDeoptimizeOnUndefined);
     if (is_truncating) SetFlag(kTruncatingToInt32);
-    if (to.IsTagged()) SetGVNFlag(kChangesNewSpacePromotion);
+    if (value->type().IsSmi()) {
+      set_type(HType::Smi());
+    } else {
+      set_type(HType::TaggedNumber());
+      if (to.IsTagged()) SetGVNFlag(kChangesNewSpacePromotion);
+    }
   }
 
   virtual HValue* EnsureAndPropagateNotMinusZero(BitVector* visited);