[turbofan] Added the RoundInt64ToFloat64 instruction to TurboFan.

src/compiler/machine-operator.h

Index: src/compiler/machine-operator.h
diff --git a/src/compiler/machine-operator.h b/src/compiler/machine-operator.h
index 2a80feecded6f01574f7c156228af6e41573c115..7cb195a79e447827ea18aab838f5e8f7b8e07ff0 100644
--- a/src/compiler/machine-operator.h
+++ b/src/compiler/machine-operator.h
@@ -192,6 +192,7 @@ class MachineOperatorBuilder final : public ZoneObject {
   const Operator* ChangeInt32ToInt64();
   const Operator* ChangeUint32ToFloat64();
   const Operator* ChangeUint32ToUint64();
+  const Operator* ChangeInt64ToFloat64();

[titzer, 2015/10/30 09:44:06]

I think we should call this "RoundInt64ToFloat64" since there is a possible loss
of precision.

[ahaas, 2015/11/02 10:35:37]

Done.

 
   // These operators truncate numbers, both changing the representation of
   // the number and mapping multiple input values onto the same output value.