Implement HChange support for Smis and use it in Load/StoreNameField

src/x64/lithium-x64.h

Index: src/x64/lithium-x64.h
diff --git a/src/x64/lithium-x64.h b/src/x64/lithium-x64.h
index 747d8e73d48c640766c4f9e6830894c62f8d94b8..baa158ace82ddfc20e3a23ff1bd6128ccf4d7ef0 100644
--- a/src/x64/lithium-x64.h
+++ b/src/x64/lithium-x64.h
@@ -95,6 +95,7 @@ class LCodeGen;
   V(Deoptimize)                                 \
   V(DivI)                                       \
   V(DoubleToI)                                  \
+  V(DoubleToSmi)                                \
   V(DummyUse)                                   \
   V(ElementsKind)                               \
   V(FixedArrayBaseLength)                       \
@@ -112,6 +113,7 @@ class LCodeGen;
   V(InstanceSize)                               \
   V(InstructionGap)                             \
   V(Integer32ToDouble)                          \
+  V(Integer32ToSmi)                             \
   V(Uint32ToDouble)                             \
   V(InvokeFunction)                             \
   V(IsConstructCallAndBranch)                   \
@@ -1887,6 +1889,19 @@ class LInteger32ToDouble: public LTemplateInstruction<1, 1, 0> {
 };
 
 
+class LInteger32ToSmi: public LTemplateInstruction<1, 1, 0> {
+ public:
+  explicit LInteger32ToSmi(LOperand* value) {
+    inputs_[0] = value;
+  }
+
+  LOperand* value() { return inputs_[0]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(Integer32ToSmi, "int32-to-smi")
+  DECLARE_HYDROGEN_ACCESSOR(Change)
+};
+
+
 class LUint32ToDouble: public LTemplateInstruction<1, 1, 1> {
  public:
   explicit LUint32ToDouble(LOperand* value, LOperand* temp) {
@@ -1958,6 +1973,19 @@ class LDoubleToI: public LTemplateInstruction<1, 1, 0> {
 };
 
 
+class LDoubleToSmi: public LTemplateInstruction<1, 1, 0> {
+ public:
+  explicit LDoubleToSmi(LOperand* value) {
+    inputs_[0] = value;
+  }
+
+  LOperand* value() { return inputs_[0]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(DoubleToSmi, "double-to-smi")
+  DECLARE_HYDROGEN_ACCESSOR(UnaryOperation)
+};
+
+
 // Truncating conversion from a tagged value to an int32.
 class LTaggedToI: public LTemplateInstruction<1, 1, 1> {
  public:
@@ -2265,7 +2293,7 @@ class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 1> {
 };
 
 
-class LCheckSmi: public LTemplateInstruction<0, 1, 0> {
+class LCheckSmi: public LTemplateInstruction<1, 1, 0> {
  public:
   explicit LCheckSmi(LOperand* value) {
     inputs_[0] = value;