[turbofan] Implemented the ChangeFloat64ToInt64 TurboFan operator.

src/compiler/mips64/instruction-selector-mips64.cc

Index: src/compiler/mips64/instruction-selector-mips64.cc
diff --git a/src/compiler/mips64/instruction-selector-mips64.cc b/src/compiler/mips64/instruction-selector-mips64.cc
index cf748fe186514d3cff310a2e6a7128281220ed7f..b689c0a7c8d9ffd726ea795ce7eaad7fc4bf4fa5 100644
--- a/src/compiler/mips64/instruction-selector-mips64.cc
+++ b/src/compiler/mips64/instruction-selector-mips64.cc
@@ -707,6 +707,11 @@ void InstructionSelector::VisitChangeFloat64ToUint32(Node* node) {
 }
 
 
+void InstructionSelector::VisitChangeFloat64ToInt64(Node* node) {
+  VisitRR(this, kMips64TruncLD, node);
+}
+
+
 void InstructionSelector::VisitChangeInt32ToInt64(Node* node) {
   Mips64OperandGenerator g(this);
   Emit(kMips64Shl, g.DefineAsRegister(node), g.UseRegister(node->InputAt(0)),