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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef jit_OffthreadSnapshot_h
#define jit_OffthreadSnapshot_h
#include "gc/Policy.h"
#include "gc/Tracer.h"
// Wrapper for GC things stored in snapshots for offthread compilation.
// Asserts the GC pointer is not nursery-allocated.
// These pointers must be traced using TraceOffthreadGCPtr.
template <typename T>
class OffthreadGCPtr {
// Note: no pre-barrier is needed because this is a constant. No post-barrier
// is needed because the value is always tenured.
const T ptr_;
public:
explicit OffthreadGCPtr(const T& ptr) : ptr_(ptr) {
MOZ_ASSERT(JS::GCPolicy<T>::isTenured(ptr),
"OffthreadSnapshot pointers must be tenured");
}
OffthreadGCPtr(const OffthreadGCPtr<T>& other) = default;
operator T() const { return ptr_; }
T operator->() const { return ptr_; }
private:
OffthreadGCPtr() = delete;
void operator=(OffthreadGCPtr<T>& other) = delete;
};
template <typename T>
inline void TraceOffthreadGCPtr(JSTracer* trc, const OffthreadGCPtr<T>& thing,
const char* name) {
T thingRaw = thing;
js::TraceManuallyBarrieredEdge(trc, &thingRaw, name);
MOZ_ASSERT(static_cast<T>(thing) == thingRaw, "Unexpected moving GC!");
}
#endif /* jit_OffthreadSnapshot_h */