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/* 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 EXTENT_H
#define EXTENT_H
#include "mozjemalloc_types.h"
#include "BaseAlloc.h"
#include "RedBlackTree.h"
#include "mozilla/UniquePtr.h"
// ***************************************************************************
// Extent data structures.
struct arena_t;
enum ChunkType;
// Tree of extents.
struct extent_node_t {
union {
// Linkage for the size/address-ordered tree for chunk recycling.
RedBlackTreeNode<extent_node_t> mLinkBySize;
// Arena id for huge allocations. It's meant to match mArena->mId,
// which only holds true when the arena hasn't been disposed of.
arena_id_t mArenaId;
};
// Linkage for the address-ordered tree.
RedBlackTreeNode<extent_node_t> mLinkByAddr;
// Pointer to the extent that this tree node is responsible for.
void* mAddr;
// Total region size.
size_t mSize;
union {
// What type of chunk is there; used for chunk recycling.
ChunkType mChunkType;
// A pointer to the associated arena, for huge allocations.
arena_t* mArena;
};
};
struct ExtentTreeSzTrait {
static RedBlackTreeNode<extent_node_t>& GetTreeNode(extent_node_t* aThis) {
return aThis->mLinkBySize;
}
static inline Order Compare(extent_node_t* aNode, extent_node_t* aOther) {
Order ret = CompareInt(aNode->mSize, aOther->mSize);
return (ret != Order::eEqual) ? ret
: CompareAddr(aNode->mAddr, aOther->mAddr);
}
};
struct ExtentTreeTrait {
static RedBlackTreeNode<extent_node_t>& GetTreeNode(extent_node_t* aThis) {
return aThis->mLinkByAddr;
}
static inline Order Compare(extent_node_t* aNode, extent_node_t* aOther) {
return CompareAddr(aNode->mAddr, aOther->mAddr);
}
};
struct ExtentTreeBoundsTrait : public ExtentTreeTrait {
static inline Order Compare(extent_node_t* aKey, extent_node_t* aNode) {
uintptr_t key_addr = reinterpret_cast<uintptr_t>(aKey->mAddr);
uintptr_t node_addr = reinterpret_cast<uintptr_t>(aNode->mAddr);
size_t node_size = aNode->mSize;
// Is aKey within aNode?
if (node_addr <= key_addr && key_addr < node_addr + node_size) {
return Order::eEqual;
}
return CompareAddr(aKey->mAddr, aNode->mAddr);
}
};
using ExtentAlloc = TypedBaseAlloc<extent_node_t>;
template <>
extent_node_t* ExtentAlloc::sFirstFree;
using UniqueBaseNode =
mozilla::UniquePtr<extent_node_t, BaseAllocFreePolicy<extent_node_t>>;
#endif /* ! EXTENT_H */