Tag length of FixedArrayBase and smi-array[x] as smi representation

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 18f64f824cf68ce9e944ebe6cb713ade9587178c..920ea0cb9205f3a27c0b551b37cc0753c9cf640f 100644
--- a/src/x64/lithium-x64.h
+++ b/src/x64/lithium-x64.h
@@ -76,6 +76,7 @@ class LCodeGen;
   V(CheckNonSmi)                                \
   V(CheckPrototypeMaps)                         \
   V(CheckSmi)                                   \
+  V(CheckSmiAndReturn)                          \
   V(ClampDToUint8)                              \
   V(ClampIToUint8)                              \
   V(ClampTToUint8)                              \
@@ -2294,7 +2295,7 @@ class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 1> {
 };
 
 
-class LCheckSmi: public LTemplateInstruction<1, 1, 0> {
+class LCheckSmi: public LTemplateInstruction<0, 1, 0> {
  public:
   explicit LCheckSmi(LOperand* value) {
     inputs_[0] = value;
@@ -2306,6 +2307,18 @@ class LCheckSmi: public LTemplateInstruction<1, 1, 0> {
 };
 
 
+class LCheckSmiAndReturn: public LTemplateInstruction<1, 1, 0> {
+ public:
+  explicit LCheckSmiAndReturn(LOperand* value) {
+    inputs_[0] = value;
+  }
+
+  LOperand* value() { return inputs_[0]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(CheckSmiAndReturn, "check-smi-and-return")
+};
+
+
 class LClampDToUint8: public LTemplateInstruction<1, 1, 0> {
  public:
   explicit LClampDToUint8(LOperand* unclamped) {