[date] Refactor the %_DateField intrinsic to be optimizable.

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 2610 matching lines @@
   safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
 }
 
 
 void LCodeGen::DoDateField(LDateField* instr) {
   Register object = ToRegister(instr->date());
   Register result = ToRegister(instr->result());
   Register temp1 = x10;
   Register temp2 = x11;
   Smi* index = instr->index();
-  Label runtime, done;
 
   DCHECK(object.is(result) && object.Is(x0));
   DCHECK(instr->IsMarkedAsCall());
 
-  DeoptimizeIfSmi(object, instr, Deoptimizer::kSmi);
-  __ CompareObjectType(object, temp1, temp1, JS_DATE_TYPE);
-  DeoptimizeIf(ne, instr, Deoptimizer::kNotADateObject);
-
   if (index->value() == 0) {
     __ Ldr(result, FieldMemOperand(object, JSDate::kValueOffset));
   } else {
+    Label runtime, done;
     if (index->value() < JSDate::kFirstUncachedField) {
       ExternalReference stamp = ExternalReference::date_cache_stamp(isolate());
       __ Mov(temp1, Operand(stamp));
       __ Ldr(temp1, MemOperand(temp1));
       __ Ldr(temp2, FieldMemOperand(object, JSDate::kCacheStampOffset));
       __ Cmp(temp1, temp2);
       __ B(ne, &runtime);
       __ Ldr(result, FieldMemOperand(object, JSDate::kValueOffset +
                                              kPointerSize * index->value()));
       __ B(&done);
     }
 
     __ Bind(&runtime);
     __ Mov(x1, Operand(index));
     __ CallCFunction(ExternalReference::get_date_field_function(isolate()), 2);
+    __ Bind(&done);
   }
-
-  __ Bind(&done);
 }
 
 
 void LCodeGen::DoDeoptimize(LDeoptimize* instr) {
   Deoptimizer::BailoutType type = instr->hydrogen()->type();
   // TODO(danno): Stubs expect all deopts to be lazy for historical reasons (the
   // needed return address), even though the implementation of LAZY and EAGER is
   // now identical. When LAZY is eventually completely folded into EAGER, remove
   // the special case below.
   if (info()->IsStub() && (type == Deoptimizer::EAGER)) {
@@ skipping 3428 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 internal
 }  // namespace v8