Inline Array.shift() fast path instead of using a code stub.

src/mips/code-stubs-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "v8.h"
 
 #if V8_TARGET_ARCH_MIPS
 
 #include "bootstrapper.h"
 #include "code-stubs.h"
@@ skipping 302 matching lines @@
 void ElementsTransitionAndStoreStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
   static Register registers[] = { a0, a3, a1, a2 };
   descriptor->register_param_count_ = 4;
   descriptor->register_params_ = registers;
   descriptor->deoptimization_handler_ =
       FUNCTION_ADDR(ElementsTransitionAndStoreIC_Miss);
 }
 
 
-void ArrayShiftStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  static Register registers[] = { a0 };
-  descriptor->register_param_count_ = 1;
-  descriptor->register_params_ = registers;
-  descriptor->deoptimization_handler_ =
-      Builtins::c_function_address(Builtins::c_ArrayShift);
-}
-
-
 void BinaryOpICStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
   static Register registers[] = { a1, a0 };
   descriptor->register_param_count_ = 2;
   descriptor->register_params_ = registers;
   descriptor->deoptimization_handler_ = FUNCTION_ADDR(BinaryOpIC_Miss);
   descriptor->SetMissHandler(
       ExternalReference(IC_Utility(IC::kBinaryOpIC_Miss), isolate()));
 }
 
@@ skipping 5141 matching lines @@
                               MemOperand(fp, 6 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS