PPC: [turbofan] Added the RoundInt64ToFloat64 instruction to TurboFan.

src/compiler/ppc/code-generator-ppc.cc

Index: src/compiler/ppc/code-generator-ppc.cc
diff --git a/src/compiler/ppc/code-generator-ppc.cc b/src/compiler/ppc/code-generator-ppc.cc
index 61e698baf1cd4c5823fe21f6136507da7ecbb992..9f3cb0c6fe5dc511441978cd443b155d883e5f82 100644
--- a/src/compiler/ppc/code-generator-ppc.cc
+++ b/src/compiler/ppc/code-generator-ppc.cc
@@ -1031,6 +1031,10 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       __ Move(i.OutputRegister(), i.InputRegister(0));
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
+    case kPPC_Int64ToDouble:
+      __ ConvertInt64ToDouble(i.InputRegister(0), i.OutputDoubleRegister());
+      DCHECK_EQ(LeaveRC, i.OutputRCBit());
+      break;
 #endif
     case kPPC_Int32ToDouble:
       __ ConvertIntToDouble(i.InputRegister(0), i.OutputDoubleRegister());