Optimize the typeof operator.

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 4e1cd8140b859d40bd92f7981de5b9d0d05a04b3..5901d1e0bf2de9fb1d8889c3985229a3f5cbe10d 100644
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -5553,10 +5553,17 @@ void LCodeGen::DoFunctionLiteral(LFunctionLiteral* instr) {
 
 
 void LCodeGen::DoTypeof(LTypeof* instr) {
+  DCHECK(ToRegister(instr->value()).is(a3));
   DCHECK(ToRegister(instr->result()).is(v0));
-  Register input = ToRegister(instr->value());
-  __ push(input);
-  CallRuntime(Runtime::kTypeof, 1, instr);
+  Label end, do_call;
+  Register value_register = ToRegister(instr->value());
+  __ JumpIfNotSmi(value_register, &do_call);
+  __ mov(v0, Immediate(isolate()->factory()->number_string()));

[paul.l..., 2015/04/28 17:03:36]

s/b: __ li(v0, Operand(isolate()->factory()->number_string()));

By convention, mips uses li 'load immediate' rather than mov.

[mvstanton, 2015/04/29 06:37:24]

Done.

+  __ jmp(&end);
+  __ bind(&do_call);
+  TypeofStub stub(isolate());
+  CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
+  __ bind(&end);
 }