1// Copyright 2015 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "CheckGCRootsVisitor.h"
6
7CheckGCRootsVisitor::CheckGCRootsVisitor() {
8}
9
10CheckGCRootsVisitor::Errors& CheckGCRootsVisitor::gc_roots() {
11  return gc_roots_;
12}
13
14bool CheckGCRootsVisitor::ContainsGCRoots(RecordInfo* info) {
15  for (RecordInfo::Fields::iterator it = info->GetFields().begin();
16       it != info->GetFields().end();
17       ++it) {
18    current_.push_back(&it->second);
19    it->second.edge()->Accept(this);
20    current_.pop_back();
21  }
22  return !gc_roots_.empty();
23}
24
25void CheckGCRootsVisitor::VisitValue(Value* edge) {
26  // TODO: what should we do to check unions?
27  if (edge->value()->record()->isUnion())
28    return;
29
30  // Prevent infinite regress for cyclic part objects.
31  if (visiting_set_.find(edge->value()) != visiting_set_.end())
32    return;
33
34  visiting_set_.insert(edge->value());
35  // If the value is a part object, then continue checking for roots.
36  for (Context::iterator it = context().begin();
37       it != context().end();
38       ++it) {
39    if (!(*it)->IsCollection())
40      return;
41  }
42  ContainsGCRoots(edge->value());
43  visiting_set_.erase(edge->value());
44}
45
46void CheckGCRootsVisitor::VisitPersistent(Persistent* edge) {
47  gc_roots_.push_back(current_);
48}
49
50void CheckGCRootsVisitor::AtCollection(Collection* edge) {
51  if (edge->is_root())
52    gc_roots_.push_back(current_);
53}
54