tools/clang/blink_gc_plugin/CheckGCRootsVisitor.cpp

   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
   7 CheckGCRootsVisitor::CheckGCRootsVisitor() {
   8 }
   9
  10 CheckGCRootsVisitor::Errors& CheckGCRootsVisitor::gc_roots() {
  11   return gc_roots_;
  12 }
  13
  14 bool 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
  25 void 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
  46 void CheckGCRootsVisitor::VisitPersistent(Persistent* edge) {
  47   gc_roots_.push_back(current_);
  48 }
  49
  50 void CheckGCRootsVisitor::AtCollection(Collection* edge) {
  51   if (edge->is_root())
  52     gc_roots_.push_back(current_);
  53 }