Merge changes to LTemplateInstruction to X64 (Issue 1048).

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index 89478f5e338485300e72f81e4427a1fd2e4027e6..b13bb0c4d837e8a89db632d9b139344e991c0261 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -996,7 +996,8 @@ HConstant::HConstant(Handle<Object> handle, Representation r)
   SetFlag(kUseGVN);
   if (handle_->IsNumber()) {
     double n = handle_->Number();
-    has_int32_value_ = static_cast<double>(static_cast<int32_t>(n)) == n;
+    double roundtrip_value = static_cast<double>(static_cast<int32_t>(n));
+    has_int32_value_ = BitCast<int64_t>(roundtrip_value) == BitCast<int64_t>(n);
     if (has_int32_value_) int32_value_ = static_cast<int32_t>(n);
     double_value_ = n;
     has_double_value_ = true;