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 #ifndef TRACEIMPL_OMITTED_TRACE_H_ 6 #define TRACEIMPL_OMITTED_TRACE_H_ 7 8 #include "heap/stubs.h" 9 10 namespace blink { 11 12 class A : public GarbageCollected<A> { 13 public: 14 virtual void Trace(Visitor* visitor) { TraceImpl(visitor); } 15 virtual void Trace(InlinedGlobalMarkingVisitor visitor) { 16 TraceImpl(visitor); 17 } 18 19 private: 20 template <typename VisitorDispatcher> 21 void TraceImpl(VisitorDispatcher visitor) {} 22 }; 23 24 class B : public A { 25 // Trace() isn't necessary because we've got nothing to trace here. 26 }; 27 28 class C : public B { 29 public: 30 void Trace(Visitor* visitor) override { TraceImpl(visitor); } 31 void Trace(InlinedGlobalMarkingVisitor visitor) override { 32 TraceImpl(visitor); 33 } 34 35 private: 36 template <typename VisitorDispatcher> 37 void TraceImpl(VisitorDispatcher visitor) { 38 // B::Trace() is actually A::Trace(), and in certain cases we only get 39 // limited information like "there is a function call that will be resolved 40 // to A::Trace()". We still want to mark B as Traced. 41 B::Trace(visitor); 42 } 43 }; 44 45 } 46 47 #endif // TRACEIMPL_OMITTED_TRACE_H_ 48
