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

src/mips/full-codegen-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 "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS
 
 // Note on Mips implementation:
 //
@@ skipping 3876 matching lines @@
   __ GetObjectType(v0, a1, a1);
   __ Branch(&done, ne, a1, Operand(JS_VALUE_TYPE));
 
   __ lw(v0, FieldMemOperand(v0, JSValue::kValueOffset));
 
   __ bind(&done);
   context()->Plug(v0);
 }
 
 
+void FullCodeGenerator::EmitThrowIfNotADate(CallRuntime* expr) {
+  ZoneList<Expression*>* args = expr->arguments();
+  DCHECK_EQ(1, args->length());
+
+  VisitForAccumulatorValue(args->at(0));  // Load the object.
+
+  Label done, not_date_object;
+  Register object = v0;
+  Register result = v0;
+  Register scratch1 = a1;
+
+  __ JumpIfSmi(object, &not_date_object);
+  __ GetObjectType(object, scratch1, scratch1);
+  __ Branch(&done, eq, scratch1, Operand(JS_DATE_TYPE));
+  __ bind(&not_date_object);
+  __ CallRuntime(Runtime::kThrowNotDateError, 0);
+
+  __ bind(&done);
+  context()->Plug(result);
+}
+
+
 void FullCodeGenerator::EmitDateField(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
   DCHECK_NOT_NULL(args->at(1)->AsLiteral());
   Smi* index = Smi::cast(*(args->at(1)->AsLiteral()->value()));
 
   VisitForAccumulatorValue(args->at(0));  // Load the object.
 
-  Label runtime, done, not_date_object;
   Register object = v0;
   Register result = v0;
   Register scratch0 = t5;
   Register scratch1 = a1;
 
-  __ JumpIfSmi(object, &not_date_object);
-  __ GetObjectType(object, scratch1, scratch1);
-  __ Branch(&not_date_object, ne, scratch1, Operand(JS_DATE_TYPE));
-
   if (index->value() == 0) {
     __ lw(result, FieldMemOperand(object, JSDate::kValueOffset));
-    __ jmp(&done);
   } else {
+    Label runtime, done;
     if (index->value() < JSDate::kFirstUncachedField) {
       ExternalReference stamp = ExternalReference::date_cache_stamp(isolate());
       __ li(scratch1, Operand(stamp));
       __ lw(scratch1, MemOperand(scratch1));
       __ lw(scratch0, FieldMemOperand(object, JSDate::kCacheStampOffset));
       __ Branch(&runtime, ne, scratch1, Operand(scratch0));
       __ lw(result, FieldMemOperand(object, JSDate::kValueOffset +
                                             kPointerSize * index->value()));
       __ jmp(&done);
     }
     __ bind(&runtime);
     __ PrepareCallCFunction(2, scratch1);
     __ li(a1, Operand(index));
     __ Move(a0, object);
     __ CallCFunction(ExternalReference::get_date_field_function(isolate()), 2);
-    __ jmp(&done);
+    __ bind(&done);
   }
 
-  __ bind(&not_date_object);
-  __ CallRuntime(Runtime::kThrowNotDateError, 0);
-  __ bind(&done);
-  context()->Plug(v0);
+  context()->Plug(result);
 }
 
 
 void FullCodeGenerator::EmitOneByteSeqStringSetChar(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK_EQ(3, args->length());
 
   Register string = v0;
   Register index = a1;
   Register value = a2;
@@ skipping 1593 matching lines @@
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS