Source code

Revision control

Other Tools

/* -*- 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 http://mozilla.org/MPL/2.0/. */
/*
* Hierarchy of SpiderMonkey system memory allocators:
*
* - System {m,c,re}alloc/new/free: Overridden by jemalloc in most
* environments. Do not use these functions directly.
*
* - js_{m,c,re}alloc/new/free: Wraps the system allocators and adds a
* failure injection framework for use by the fuzzers as well as templated,
* typesafe variants. See js/public/Utility.h.
*
* - AllocPolicy: An interface for the js allocators, for use with templates.
* These allocators are for system memory whose lifetime is not associated
* with a GC thing. See js/public/AllocPolicy.h.
*
* - SystemAllocPolicy: No extra functionality over bare allocators.
*
* - TempAllocPolicy: Adds automatic error reporting to the provided
* JSContext when allocations fail.
*
* - ZoneAllocPolicy: Forwards to the Zone MallocProvider.
*
* - MallocProvider. A mixin base class that handles automatically updating
* the GC's state in response to allocations that are tied to a GC lifetime
* or are for a particular GC purpose. These allocators must only be used
* for memory that will be freed when a GC thing is swept.
*
* - gc::Zone: Automatically triggers zone GC.
* - JSRuntime: Automatically triggers full GC.
* - JSContext: Dispatches directly to the runtime.
*/
#ifndef vm_MallocProvider_h
#define vm_MallocProvider_h
#include "mozilla/Attributes.h" // MOZ_ALWAYS_INLINE
#include "mozilla/Likely.h" // MOZ_LIKELY, MOZ_UNLIKELY
#include <stddef.h> // size_t
#include <stdint.h> // uint8_t
#include "js/AllocPolicy.h" // AllocFunction
#include "js/UniquePtr.h" // UniquePtr
#include "js/Utility.h" // js_malloc, MallocArena, CalculateAllocSize, CalculateAllocSizeWithExtra, JS::FreePolicy
namespace js {
template <class Client>
struct MallocProvider {
template <class T>
T* maybe_pod_arena_malloc(arena_id_t arena, size_t numElems) {
T* p = js_pod_arena_malloc<T>(arena, numElems);
if (MOZ_LIKELY(p)) {
client()->updateMallocCounter(numElems * sizeof(T));
}
return p;
}
template <class T>
T* maybe_pod_arena_calloc(arena_id_t arena, size_t numElems) {
T* p = js_pod_arena_calloc<T>(arena, numElems);
if (MOZ_LIKELY(p)) {
client()->updateMallocCounter(numElems * sizeof(T));
}
return p;
}
template <class T>
T* maybe_pod_arena_realloc(arena_id_t arena, T* prior, size_t oldSize,
size_t newSize) {
T* p = js_pod_arena_realloc<T>(arena, prior, oldSize, newSize);
if (MOZ_LIKELY(p)) {
// For compatibility we do not account for realloc that decreases
// previously allocated memory.
if (newSize > oldSize) {
client()->updateMallocCounter((newSize - oldSize) * sizeof(T));
}
}
return p;
}
template <class T>
T* maybe_pod_malloc(size_t numElems) {
return maybe_pod_arena_malloc<T>(js::MallocArena, numElems);
}
template <class T>
T* maybe_pod_calloc(size_t numElems) {
return maybe_pod_arena_calloc<T>(js::MallocArena, numElems);
}
template <class T>
T* maybe_pod_realloc(T* prior, size_t oldSize, size_t newSize) {
return maybe_pod_arena_realloc<T>(js::MallocArena, prior, oldSize, newSize);
}
template <class T>
T* pod_malloc() {
return pod_malloc<T>(1);
}
template <class T>
T* pod_arena_malloc(arena_id_t arena, size_t numElems) {
T* p = maybe_pod_arena_malloc<T>(arena, numElems);
if (MOZ_LIKELY(p)) {
return p;
}
size_t bytes;
if (MOZ_UNLIKELY(!CalculateAllocSize<T>(numElems, &bytes))) {
client()->reportAllocationOverflow();
return nullptr;
}
p = (T*)client()->onOutOfMemory(AllocFunction::Malloc, arena, bytes);
if (p) {
client()->updateMallocCounter(bytes);
}
return p;
}
template <class T>
T* pod_malloc(size_t numElems) {
return pod_arena_malloc<T>(js::MallocArena, numElems);
}
template <class T, class U>
T* pod_malloc_with_extra(size_t numExtra) {
size_t bytes;
if (MOZ_UNLIKELY((!CalculateAllocSizeWithExtra<T, U>(numExtra, &bytes)))) {
client()->reportAllocationOverflow();
return nullptr;
}
T* p = static_cast<T*>(js_malloc(bytes));
if (MOZ_LIKELY(p)) {
client()->updateMallocCounter(bytes);
return p;
}
p = (T*)client()->onOutOfMemory(AllocFunction::Malloc, js::MallocArena,
bytes);
if (p) {
client()->updateMallocCounter(bytes);
}
return p;
}
template <class T>
UniquePtr<T[], JS::FreePolicy> make_pod_arena_array(arena_id_t arena,
size_t numElems) {
return UniquePtr<T[], JS::FreePolicy>(pod_arena_malloc<T>(arena, numElems));
}
template <class T>
UniquePtr<T[], JS::FreePolicy> make_pod_array(size_t numElems) {
return make_pod_arena_array<T>(js::MallocArena, numElems);
}
template <class T>
T* pod_arena_calloc(arena_id_t arena, size_t numElems = 1) {
T* p = maybe_pod_arena_calloc<T>(arena, numElems);
if (MOZ_LIKELY(p)) {
return p;
}
size_t bytes;
if (MOZ_UNLIKELY(!CalculateAllocSize<T>(numElems, &bytes))) {
client()->reportAllocationOverflow();
return nullptr;
}
p = (T*)client()->onOutOfMemory(AllocFunction::Calloc, arena, bytes);
if (p) {
client()->updateMallocCounter(bytes);
}
return p;
}
template <class T>
T* pod_calloc(size_t numElems = 1) {
return pod_arena_calloc<T>(js::MallocArena, numElems);
}
template <class T, class U>
T* pod_calloc_with_extra(size_t numExtra) {
size_t bytes;
if (MOZ_UNLIKELY((!CalculateAllocSizeWithExtra<T, U>(numExtra, &bytes)))) {
client()->reportAllocationOverflow();
return nullptr;
}
T* p = static_cast<T*>(js_calloc(bytes));
if (p) {
client()->updateMallocCounter(bytes);
return p;
}
p = (T*)client()->onOutOfMemory(AllocFunction::Calloc, js::MallocArena,
bytes);
if (p) {
client()->updateMallocCounter(bytes);
}
return p;
}
template <class T>
UniquePtr<T[], JS::FreePolicy> make_zeroed_pod_array(size_t numElems) {
return UniquePtr<T[], JS::FreePolicy>(pod_calloc<T>(numElems));
}
template <class T>
T* pod_arena_realloc(arena_id_t arena, T* prior, size_t oldSize,
size_t newSize) {
T* p = maybe_pod_arena_realloc(arena, prior, oldSize, newSize);
if (MOZ_LIKELY(p)) {
return p;
}
size_t bytes;
if (MOZ_UNLIKELY(!CalculateAllocSize<T>(newSize, &bytes))) {
client()->reportAllocationOverflow();
return nullptr;
}
p = (T*)client()->onOutOfMemory(AllocFunction::Realloc, arena, bytes,
prior);
if (p && newSize > oldSize) {
client()->updateMallocCounter((newSize - oldSize) * sizeof(T));
}
return p;
}
template <class T>
T* pod_realloc(T* prior, size_t oldSize, size_t newSize) {
return pod_arena_realloc<T>(js::MallocArena, prior, oldSize, newSize);
}
JS_DECLARE_NEW_METHODS(new_, pod_malloc<uint8_t>, MOZ_ALWAYS_INLINE)
JS_DECLARE_NEW_ARENA_METHODS(
arena_new_,
[this](arena_id_t arena, size_t size) {
return pod_malloc<uint8_t>(size, arena);
},
MOZ_ALWAYS_INLINE)
JS_DECLARE_MAKE_METHODS(make_unique, new_, MOZ_ALWAYS_INLINE)
JS_DECLARE_MAKE_METHODS(arena_make_unique, arena_new_, MOZ_ALWAYS_INLINE)
private:
Client* client() { return static_cast<Client*>(this); }
// The Default implementation is a no-op which can be overridden by the
// client.
void updateMallocCounter(size_t nbytes) {}
};
} /* namespace js */
#endif /* vm_MallocProvider_h */