[turbofan] Add TruncationMode for TruncateFloat64ToInt32.

src/compiler/arm64/instruction-selector-arm64.cc

Index: src/compiler/arm64/instruction-selector-arm64.cc
diff --git a/src/compiler/arm64/instruction-selector-arm64.cc b/src/compiler/arm64/instruction-selector-arm64.cc
index 7c1c1d76fa768f76d83cf1e651d9ab81027a5fb8..ca0ec4e40063b31ddd4539a3d2178d511e9556b8 100644
--- a/src/compiler/arm64/instruction-selector-arm64.cc
+++ b/src/compiler/arm64/instruction-selector-arm64.cc
@@ -1237,9 +1237,18 @@ void InstructionSelector::VisitChangeUint32ToUint64(Node* node) {
 
 
 void InstructionSelector::VisitTruncateFloat64ToFloat32(Node* node) {
-  Arm64OperandGenerator g(this);
-  Emit(kArm64Float64ToFloat32, g.DefineAsRegister(node),
-       g.UseRegister(node->InputAt(0)));
+  VisitRR(this, kArm64Float64ToFloat32, node);
+}
+
+
+void InstructionSelector::VisitTruncateFloat64ToInt32(Node* node) {
+  switch (TruncationModeOf(node->op())) {
+    case TruncationMode::kJavaScript:
+      return VisitRR(this, kArchTruncateDoubleToI, node);
+    case TruncationMode::kRoundToZero:
+      return VisitRR(this, kArm64Float64ToInt32, node);
+  }
+  UNREACHABLE();
 }