Optimize array-length and fast element loads....

src/arm/lithium-arm.h

Index: src/arm/lithium-arm.h
===================================================================
--- src/arm/lithium-arm.h	(revision 6124)
+++ src/arm/lithium-arm.h	(working copy)
@@ -101,7 +101,8 @@
 //     LStoreNamedField
 //     LStoreNamedGeneric
 //   LUnaryOperation
-//     LArrayLength
+//     LJSArrayLength
+//     LFixedArrayLength
 //     LBitNotI
 //     LBranch
 //     LCallNew
@@ -162,7 +163,6 @@
   V(ArgumentsLength)                            \
   V(ArithmeticD)                                \
   V(ArithmeticT)                                \
-  V(ArrayLength)                                \
   V(ArrayLiteral)                               \
   V(BitI)                                       \
   V(BitNotI)                                    \
@@ -196,6 +196,7 @@
   V(Deoptimize)                                 \
   V(DivI)                                       \
   V(DoubleToI)                                  \
+  V(FixedArrayLength)                           \
   V(FunctionLiteral)                            \
   V(Gap)                                        \
   V(GlobalObject)                               \
@@ -210,6 +211,7 @@
   V(IsObjectAndBranch)                          \
   V(IsSmi)                                      \
   V(IsSmiAndBranch)                             \
+  V(JSArrayLength)                              \
   V(HasInstanceType)                            \
   V(HasInstanceTypeAndBranch)                   \
   V(HasCachedArrayIndex)                        \
@@ -1143,18 +1145,21 @@
 };
 
 
-class LArrayLength: public LUnaryOperation {
+class LJSArrayLength: public LUnaryOperation {
  public:
-  LArrayLength(LOperand* input, LOperand* temporary)
-      : LUnaryOperation(input), temporary_(temporary) { }
+  explicit LJSArrayLength(LOperand* input) : LUnaryOperation(input) { }
 
-  LOperand* temporary() const { return temporary_; }
+  DECLARE_CONCRETE_INSTRUCTION(JSArrayLength, "js-array-length")
+  DECLARE_HYDROGEN_ACCESSOR(JSArrayLength)
+};
 
-  DECLARE_CONCRETE_INSTRUCTION(ArrayLength, "array-length")
-  DECLARE_HYDROGEN_ACCESSOR(ArrayLength)
 
- private:
-  LOperand* temporary_;
+class LFixedArrayLength: public LUnaryOperation {
+ public:
+  explicit LFixedArrayLength(LOperand* input) : LUnaryOperation(input) { }
+
+  DECLARE_CONCRETE_INSTRUCTION(FixedArrayLength, "fixed-array-length")
+  DECLARE_HYDROGEN_ACCESSOR(FixedArrayLength)
 };