Optimize the typeof operator.

src/arm64/lithium-codegen-arm64.cc

 // Copyright 2013 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 "src/v8.h"
 
 #include "src/arm64/lithium-codegen-arm64.h"
 #include "src/arm64/lithium-gap-resolver-arm64.h"
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 5764 matching lines @@
   DoubleRegister input = ToDoubleRegister(instr->value());
   Register result = ToRegister(instr->result());
   __ TruncateDoubleToI(result, input);
   if (instr->tag_result()) {
     __ SmiTag(result, result);
   }
 }
 
 
 void LCodeGen::DoTypeof(LTypeof* instr) {
-  Register input = ToRegister(instr->value());
-  __ Push(input);
-  CallRuntime(Runtime::kTypeof, 1, instr);
+  DCHECK(ToRegister(instr->value()).is(x3));
+  DCHECK(ToRegister(instr->result()).is(x0));
+  Label end, do_call;
+  Register value_register = ToRegister(instr->value());
+  __ JumpIfNotSmi(value_register, &do_call);
+  __ Mov(x0, Immediate(isolate()->factory()->number_string()));
+  __ B(&end);
+  __ Bind(&do_call);
+  TypeofStub stub(isolate());
+  CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
+  __ Bind(&end);
 }
 
 
 void LCodeGen::DoTypeofIsAndBranch(LTypeofIsAndBranch* instr) {
   Handle<String> type_name = instr->type_literal();
   Label* true_label = instr->TrueLabel(chunk_);
   Label* false_label = instr->FalseLabel(chunk_);
   Register value = ToRegister(instr->value());
 
   Factory* factory = isolate()->factory();
@@ skipping 230 matching lines @@
   Handle<ScopeInfo> scope_info = instr->scope_info();
   __ Push(scope_info);
   __ Push(ToRegister(instr->function()));
   CallRuntime(Runtime::kPushBlockContext, 2, instr);
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 
 } }  // namespace v8::internal