[turbofan] Added the RoundInt64ToFloat64 instruction to TurboFan.

src/compiler/ia32/instruction-selector-ia32.cc

Index: src/compiler/ia32/instruction-selector-ia32.cc
diff --git a/src/compiler/ia32/instruction-selector-ia32.cc b/src/compiler/ia32/instruction-selector-ia32.cc
index c19a4e0e41ba90885db18339a7b5ac273eb26db0..dc888e5c2861731af14b0125a99c02b873a27476 100644
--- a/src/compiler/ia32/instruction-selector-ia32.cc
+++ b/src/compiler/ia32/instruction-selector-ia32.cc
@@ -668,6 +668,11 @@ void InstructionSelector::VisitChangeInt32ToFloat64(Node* node) {
 }
 
 
+void InstructionSelector::VisitChangeInt64ToFloat64(Node* node) {
+  UNIMPLEMENTED();
+}
+
+
 void InstructionSelector::VisitChangeUint32ToFloat64(Node* node) {
   VisitRO(this, node, kSSEUint32ToFloat64);
 }