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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
* file, You can obtain one at */
#ifndef js_AllocationRecording_h
#define js_AllocationRecording_h
#include <stdint.h>
#include "jstypes.h"
#include "js/TypeDecls.h"
namespace JS {
* This struct holds the information needed to create a profiler marker payload
* that can represent a JS allocation. It translates JS engine specific classes,
* into something that can be used in the profiler.
struct RecordAllocationInfo {
RecordAllocationInfo(const char16_t* typeName, const char* className,
const char16_t* descriptiveTypeName,
const char* coarseType, uint64_t size, bool inNursery)
: typeName(typeName),
inNursery(inNursery) {}
// These pointers are borrowed from the UbiNode, and can point to live data.
// It is important for the consumers of this struct to correctly
// duplicate the strings to take ownership of them.
const char16_t* typeName;
const char* className;
const char16_t* descriptiveTypeName;
// The coarseType points to a string literal, so does not need to be
// duplicated.
const char* coarseType;
// The size in bytes of the allocation.
uint64_t size;
// Whether or not the allocation is in the nursery or not.
bool inNursery;
typedef void (*RecordAllocationsCallback)(RecordAllocationInfo&& info);
* Enable recording JS allocations. This feature hooks into the object creation
* in the JavaScript engine, and reports back the allocation info through the
* callback. This allocation tracking is turned on for all encountered realms.
* The JS Debugger API can also turn on allocation tracking with its own
* probability. If both allocation tracking mechanisms are turned on at the same
* time, the Debugger's probability defers to the EnableRecordingAllocations's
* probability setting.
JS_PUBLIC_API void EnableRecordingAllocations(
JSContext* cx, RecordAllocationsCallback callback, double probability);
* Turn off JS allocation recording. If any JS Debuggers are also recording
* allocations, then the probability will be reset to the Debugger's desired
* setting.
JS_PUBLIC_API void DisableRecordingAllocations(JSContext* cx);
} // namespace JS
#endif /* js_AllocationRecording_h */