Constant-folding through HForceRepresentation fix.

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index 38eabdae06aa5d9968d1479e050e883ff7b707f2..33ab8797252b9880a50fb3a3f2deff5f8a9f9ca9 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -521,19 +521,12 @@ bool HValue::CanReplaceWithDummyUses() {
 
 
 bool HValue::IsInteger32Constant() {
-  HValue* value_to_check = IsForceRepresentation()
-      ? HForceRepresentation::cast(this)->value()
-      : this;
-  return value_to_check->IsConstant() &&
-      HConstant::cast(value_to_check)->HasInteger32Value();
+  return IsConstant() && HConstant::cast(this)->HasInteger32Value();
 }
 
 
 int32_t HValue::GetInteger32Constant() {
-  HValue* constant_value = IsForceRepresentation()
-      ? HForceRepresentation::cast(this)->value()
-      : this;
-  return HConstant::cast(constant_value)->Integer32Value();
+  return HConstant::cast(this)->Integer32Value();
 }
 
 
@@ -1328,6 +1321,23 @@ void HTypeof::PrintDataTo(StringStream* stream) {
 }
 
 
+HInstruction* HForceRepresentation::New(Zone* zone, HValue* context,
+       HValue* value, Representation required_representation) {
+  if (FLAG_fold_constants && value->IsConstant()) {
+    HConstant* c = HConstant::cast(value);
+    if ((c->HasNumberValue())) {

[mvstanton, 2013/11/19 10:22:28]

nit: remove extra parens

[Igor Sheludko, 2013/11/19 11:43:35]

Done.

+      double double_res = c->DoubleValue();
+      if (TypeInfo::IsInt32Double(double_res)) {
+        return HConstant::New(zone, context,
+                              static_cast<int32_t>(double_res),
+                              required_representation);
+      }
+    }
+  }
+  return new(zone) HForceRepresentation(value, required_representation);
+}
+
+
 void HForceRepresentation::PrintDataTo(StringStream* stream) {
   stream->Add("%s ", representation().Mnemonic());
   value()->PrintNameTo(stream);