[es6] Introduce a dedicated JSIteratorResult type.

src/full-codegen/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.
 
 #if V8_TARGET_ARCH_MIPS
 
 // Note on Mips implementation:
 //
 // The result_register() for mips is the 'v0' register, which is defined
 // by the ABI to contain function return values. However, the first
@@ skipping 2248 matching lines @@
   __ CallRuntime(Runtime::kResumeJSGeneratorObject, 3);
   // Not reached: the runtime call returns elsewhere.
   __ stop("not-reached");
 
   __ bind(&done);
   context()->Plug(result_register());
 }
 
 
 void FullCodeGenerator::EmitCreateIteratorResult(bool done) {
-  Label gc_required;
-  Label allocated;
+  Label allocate, done_allocate;
 
-  const int instance_size = 5 * kPointerSize;
-  DCHECK_EQ(isolate()->native_context()->iterator_result_map()->instance_size(),
-            instance_size);
+  __ Allocate(JSIteratorResult::kSize, v0, a2, a3, &allocate, TAG_OBJECT);
+  __ jmp(&done_allocate);
 
-  __ Allocate(instance_size, v0, a2, a3, &gc_required, TAG_OBJECT);
-  __ jmp(&allocated);
+  __ bind(&allocate);
+  __ Push(Smi::FromInt(JSIteratorResult::kSize));
+  __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
 
-  __ bind(&gc_required);
-  __ Push(Smi::FromInt(instance_size));
-  __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-  __ lw(context_register(),
-        MemOperand(fp, StandardFrameConstants::kContextOffset));
-
-  __ bind(&allocated);
+  __ bind(&done_allocate);
   __ lw(a1, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
   __ lw(a1, FieldMemOperand(a1, GlobalObject::kNativeContextOffset));
   __ lw(a1, ContextOperand(a1, Context::ITERATOR_RESULT_MAP_INDEX));
   __ pop(a2);
   __ li(a3, Operand(isolate()->factory()->ToBoolean(done)));
   __ li(t0, Operand(isolate()->factory()->empty_fixed_array()));
   __ sw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
   __ sw(t0, FieldMemOperand(v0, JSObject::kPropertiesOffset));
   __ sw(t0, FieldMemOperand(v0, JSObject::kElementsOffset));
-  __ sw(a2,
-        FieldMemOperand(v0, JSGeneratorObject::kResultValuePropertyOffset));
-  __ sw(a3,
-        FieldMemOperand(v0, JSGeneratorObject::kResultDonePropertyOffset));
-
-  // Only the value field needs a write barrier, as the other values are in the
-  // root set.
-  __ RecordWriteField(v0, JSGeneratorObject::kResultValuePropertyOffset,
-                      a2, a3, kRAHasBeenSaved, kDontSaveFPRegs);
+  __ sw(a2, FieldMemOperand(v0, JSIteratorResult::kValueOffset));
+  __ sw(a3, FieldMemOperand(v0, JSIteratorResult::kDoneOffset));
+  STATIC_ASSERT(JSIteratorResult::kSize == 5 * kPointerSize);
 }
 
 
 void FullCodeGenerator::EmitNamedPropertyLoad(Property* prop) {
   SetExpressionPosition(prop);
   Literal* key = prop->key()->AsLiteral();
   DCHECK(!prop->IsSuperAccess());
 
   __ li(LoadDescriptor::NameRegister(), Operand(key->value()));
   __ li(LoadDescriptor::SlotRegister(),
@@ skipping 2178 matching lines @@
   DCHECK(expr->arguments()->length() == 0);
   ExternalReference debug_is_active =
       ExternalReference::debug_is_active_address(isolate());
   __ li(at, Operand(debug_is_active));
   __ lb(v0, MemOperand(at));
   __ SmiTag(v0);
   context()->Plug(v0);
 }
 
 
+void FullCodeGenerator::EmitCreateIterResultObject(CallRuntime* expr) {
+  ZoneList<Expression*>* args = expr->arguments();
+  DCHECK_EQ(2, args->length());
+  VisitForStackValue(args->at(0));
+  VisitForStackValue(args->at(1));
+
+  Label runtime, done;
+
+  __ Allocate(JSIteratorResult::kSize, v0, a2, a3, &runtime, TAG_OBJECT);
+  __ lw(a1, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
+  __ lw(a1, FieldMemOperand(a1, GlobalObject::kNativeContextOffset));
+  __ lw(a1, ContextOperand(a1, Context::ITERATOR_RESULT_MAP_INDEX));
+  __ pop(a3);
+  __ pop(a2);
+  __ li(t0, Operand(isolate()->factory()->empty_fixed_array()));
+  __ sw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
+  __ sw(t0, FieldMemOperand(v0, JSObject::kPropertiesOffset));
+  __ sw(t0, FieldMemOperand(v0, JSObject::kElementsOffset));
+  __ sw(a2, FieldMemOperand(v0, JSIteratorResult::kValueOffset));
+  __ sw(a3, FieldMemOperand(v0, JSIteratorResult::kDoneOffset));
+  STATIC_ASSERT(JSIteratorResult::kSize == 5 * kPointerSize);
+  __ jmp(&done);
+
+  __ bind(&runtime);
+  __ CallRuntime(Runtime::kCreateIterResultObject, 2);
+
+  __ bind(&done);
+  context()->Plug(v0);
+}
+
+
 void FullCodeGenerator::EmitLoadJSRuntimeFunction(CallRuntime* expr) {
   // Push undefined as the receiver.
   __ LoadRoot(v0, Heap::kUndefinedValueRootIndex);
   __ push(v0);
 
   __ lw(v0, GlobalObjectOperand());
   __ lw(v0, FieldMemOperand(v0, GlobalObject::kNativeContextOffset));
   __ lw(v0, ContextOperand(v0, expr->context_index()));
 }
 
@@ skipping 809 matching lines @@
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS