Mypal/js/src/wasm/WasmCompartment.h

108 lines
3.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
*
* Copyright 2016 Mozilla Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef wasm_compartment_h
#define wasm_compartment_h
#include "wasm/WasmJS.h"
namespace js {
class WasmActivation;
namespace wasm {
class Code;
typedef Vector<Instance*, 0, SystemAllocPolicy> InstanceVector;
// wasm::Compartment lives in JSCompartment and contains the wasm-related
// per-compartment state. wasm::Compartment tracks every live instance in the
// compartment and must be notified, via registerInstance(), of any new
// WasmInstanceObject.
class Compartment
{
InstanceVector instances_;
volatile bool mutatingInstances_;
size_t activationCount_;
bool profilingEnabled_;
friend class js::WasmActivation;
struct AutoMutateInstances {
Compartment &c;
explicit AutoMutateInstances(Compartment& c) : c(c) {
MOZ_ASSERT(!c.mutatingInstances_);
c.mutatingInstances_ = true;
}
~AutoMutateInstances() {
MOZ_ASSERT(c.mutatingInstances_);
c.mutatingInstances_ = false;
}
};
public:
explicit Compartment(Zone* zone);
~Compartment();
void trace(JSTracer* trc);
// Before a WasmInstanceObject can be considered fully constructed and
// valid, it must be registered with the Compartment. If this method fails,
// an error has been reported and the instance object must be abandoned.
// After a successful registration, an Instance must call
// unregisterInstance() before being destroyed.
bool registerInstance(JSContext* cx, HandleWasmInstanceObject instanceObj);
void unregisterInstance(Instance& instance);
// Return a vector of all live instances in the compartment. The lifetime of
// these Instances is determined by their owning WasmInstanceObject.
// Note that accessing instances()[i]->object() triggers a read barrier
// since instances() is effectively a weak list.
const InstanceVector& instances() const { return instances_; }
// This methods returns the wasm::Code containing the given pc, if any
// exists in the compartment.
Code* lookupCode(const void* pc) const;
// Currently, there is one Code per Instance so it is also possible to
// lookup a Instance given a pc. However, the goal is to share one Code
// between multiple Instances at which point in time this method will be
// removed.
Instance* lookupInstanceDeprecated(const void* pc) const;
// To ensure profiling is enabled (so that wasm frames are not lost in
// profiling callstacks), ensureProfilingState must be called before calling
// the first wasm function in a compartment.
bool ensureProfilingState(JSContext* cx);
bool profilingEnabled() const;
// about:memory reporting
void addSizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf, size_t* compartmentTables);
};
} // namespace wasm
} // namespace js
#endif // wasm_compartment_h