Various extensions to types

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/296213005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21494 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/conversions.h

@@ -163,6 +163,17 @@ static inline bool IsInt32Double(double value) {
 }
 
 
+// UInteger32 is an integer that can be represented as an unsigned 32-bit
+// integer. It has to be in the range [0, 2^32 - 1].
+// We also have to check for negative 0 as it is not a UInteger32.
+static inline bool IsUint32Double(double value) {
+  return !IsMinusZero(value) &&
+         value >= 0 &&
+         value <= kMaxUInt32 &&
+         value == FastUI2D(FastD2UI(value));
+}
+
+
 // Convert from Number object to C integer.
 inline int32_t NumberToInt32(Object* number) {
   if (number->IsSmi()) return Smi::cast(number)->value();

src/hydrogen.cc

@@ -9503,7 +9503,7 @@ HValue* HGraphBuilder::TruncateToNumber(HValue* value, Type** expected) {
 
   if (expected_obj->Is(Type::Undefined(zone()))) {
     // This is already done by HChange.
-    *expected = Type::Union(expected_number, Type::Float(zone()), zone());
+    *expected = Type::Union(expected_number, Type::Number(zone()), zone());
     return value;
   }
 

src/types-inl.h

@@ -20,7 +20,7 @@ template<class Config>
 TypeImpl<Config>* TypeImpl<Config>::cast(typename Config::Base* object) {
   TypeImpl* t = static_cast<TypeImpl*>(object);
   ASSERT(t->IsBitset() || t->IsClass() || t->IsConstant() ||
-         t->IsUnion() || t->IsArray() || t->IsFunction());
+         t->IsUnion() || t->IsArray() || t->IsFunction() || t->IsContext());
   return t;
 }