[turbofan] Refactor IsSame into NodeProperties.

src/compiler/js-inlining.cc

 // Copyright 2014 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/js-inlining.h"
 
 #include "src/ast/ast.h"
 #include "src/compilation-info.h"
 #include "src/compiler.h"
 #include "src/compiler/all-nodes.h"
@@ skipping 260 matching lines @@
       BailoutId(-1), OutputFrameStateCombine::Ignore(), state_info);
   const Operator* op0 = common()->StateValues(0, SparseInputMask::Dense());
   Node* node0 = graph()->NewNode(op0);
   return graph()->NewNode(op, node0, node0, node0,
                           jsgraph()->UndefinedConstant(), function,
                           frame_state);
 }
 
 namespace {
 
-// TODO(turbofan): Shall we move this to the NodeProperties? Or some (untyped)
-// alias analyzer?
-bool IsSame(Node* a, Node* b) {
-  if (a == b) {
-    return true;
-  } else if (a->opcode() == IrOpcode::kCheckHeapObject) {
-    return IsSame(a->InputAt(0), b);
-  } else if (b->opcode() == IrOpcode::kCheckHeapObject) {
-    return IsSame(a, b->InputAt(0));
-  }
-  return false;
-}
-
 // TODO(bmeurer): Unify this with the witness helper functions in the
 // js-builtin-reducer.cc once we have a better understanding of the
 // map tracking we want to do, and eventually changed the CheckMaps
 // operator to carry map constants on the operator instead of inputs.
 // I.e. if the CheckMaps has some kind of SmallMapSet as operator
 // parameter, then this could be changed to call a generic
 //
 //   SmallMapSet NodeProperties::CollectMapWitness(receiver, effect)
 //
 // function, which either returns the map set from the CheckMaps or
 // a singleton set from a StoreField.
 bool NeedsConvertReceiver(Node* receiver, Node* effect) {
   for (Node* dominator = effect;;) {
     if (dominator->opcode() == IrOpcode::kCheckMaps &&
-        IsSame(dominator->InputAt(0), receiver)) {
+        NodeProperties::IsSame(dominator->InputAt(0), receiver)) {
       // Check if all maps have the given {instance_type}.
       ZoneHandleSet<Map> const& maps =
           CheckMapsParametersOf(dominator->op()).maps();
       for (size_t i = 0; i < maps.size(); ++i) {
         if (!maps[i]->IsJSReceiverMap()) return true;
       }
       return false;
     }
     switch (dominator->opcode()) {
       case IrOpcode::kStoreField: {
@@ skipping 351 matching lines @@
 
 CommonOperatorBuilder* JSInliner::common() const { return jsgraph()->common(); }
 
 SimplifiedOperatorBuilder* JSInliner::simplified() const {
   return jsgraph()->simplified();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8