MIPS: Improve Array.shift() performance for small arrays.

src/mips/lithium-codegen-mips.cc

Index: src/mips/lithium-codegen-mips.cc
diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index 95ee3a6c12dd2c2b1ced217c8b2193372775a5ee..b731baa321a790cd5ef8436b34a7dd90153ef38e 100644
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -4442,6 +4442,15 @@ void LCodeGen::DoTransitionElementsKind(LTransitionElementsKind* instr) {
 }
 
 
+void LCodeGen::DoArrayShift(LArrayShift* instr) {
+  ASSERT(ToRegister(instr->context()).is(cp));
+  ASSERT(ToRegister(instr->object()).is(a0));
+  ASSERT(ToRegister(instr->result()).is(v0));
+  ArrayShiftStub stub(isolate(), instr->hydrogen()->kind());
+  CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
+}
+
+
 void LCodeGen::DoTrapAllocationMemento(LTrapAllocationMemento* instr) {
   Register object = ToRegister(instr->object());
   Register temp = ToRegister(instr->temp());