[es6] Reintroduce the instanceof operator in the backends.

src/compiler/code-assembler.cc

 // Copyright 2015 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/compiler/code-assembler.h"
 
 #include <ostream>
 
 #include "src/code-factory.h"
 #include "src/compiler/graph.h"
@@ skipping 187 matching lines @@
 Node* CodeAssembler::LoadRoot(Heap::RootListIndex root_index) {
   if (isolate()->heap()->RootCanBeTreatedAsConstant(root_index)) {
     Handle<Object> root = isolate()->heap()->root_handle(root_index);
     if (root->IsSmi()) {
       return SmiConstant(Smi::cast(*root));
     } else {
       return HeapConstant(Handle<HeapObject>::cast(root));
     }
   }
 
-  compiler::Node* roots_array_start =
+  Node* roots_array_start =
       ExternalConstant(ExternalReference::roots_array_start(isolate()));
-  USE(roots_array_start);
-
-  // TODO(danno): Implement the root-access case where the root is not constant
-  // and must be loaded from the root array.
-  UNIMPLEMENTED();
-  return nullptr;
+  return Load(MachineType::AnyTagged(), roots_array_start,
+              IntPtrConstant(root_index * kPointerSize));
 }
 
 Node* CodeAssembler::Store(MachineRepresentation rep, Node* base, Node* value) {
   return raw_assembler_->Store(rep, base, value, kFullWriteBarrier);
 }
 
 Node* CodeAssembler::Store(MachineRepresentation rep, Node* base, Node* index,
                            Node* value) {
   return raw_assembler_->Store(rep, base, index, value, kFullWriteBarrier);
 }
 
 Node* CodeAssembler::StoreNoWriteBarrier(MachineRepresentation rep, Node* base,
                                          Node* value) {
   return raw_assembler_->Store(rep, base, value, kNoWriteBarrier);
 }
 
 Node* CodeAssembler::StoreNoWriteBarrier(MachineRepresentation rep, Node* base,
                                          Node* index, Node* value) {
   return raw_assembler_->Store(rep, base, index, value, kNoWriteBarrier);
 }
 
 Node* CodeAssembler::AtomicStore(MachineRepresentation rep, Node* base,
                                  Node* index, Node* value) {
   return raw_assembler_->AtomicStore(rep, base, index, value);
 }
 
+Node* CodeAssembler::StoreRoot(Heap::RootListIndex root_index, Node* value) {
+  DCHECK(Heap::RootCanBeWrittenAfterInitialization(root_index));
+  Node* roots_array_start =
+      ExternalConstant(ExternalReference::roots_array_start(isolate()));
+  return StoreNoWriteBarrier(MachineRepresentation::kTagged, roots_array_start,
+                             IntPtrConstant(root_index * kPointerSize), value);
+}
+
 Node* CodeAssembler::Projection(int index, Node* value) {
   return raw_assembler_->Projection(index, value);
 }
 
 void CodeAssembler::BranchIf(Node* condition, Label* if_true, Label* if_false) {
   Label if_condition_is_true(this), if_condition_is_false(this);
   Branch(condition, &if_condition_is_true, &if_condition_is_false);
   Bind(&if_condition_is_true);
   Goto(if_true);
   Bind(&if_condition_is_false);
@@ skipping 443 matching lines @@
       }
     }
   }
 
   bound_ = true;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8