1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/base/nsPresArena.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,136 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
1.5 + * vim: set ts=2 sw=2 et tw=78:
1.6 + * This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/.
1.9 + */
1.10 +
1.11 +/* arena allocation for the frame tree and closely-related objects */
1.12 +
1.13 +#ifndef nsPresArena_h___
1.14 +#define nsPresArena_h___
1.15 +
1.16 +#include "mozilla/MemoryChecking.h" // Note: Do not remove this, needed for MOZ_HAVE_MEM_CHECKS below
1.17 +#include "mozilla/MemoryReporting.h"
1.18 +#include <stdint.h>
1.19 +#include "nscore.h"
1.20 +#include "nsQueryFrame.h"
1.21 +#include "nsTArray.h"
1.22 +#include "nsTHashtable.h"
1.23 +#include "plarena.h"
1.24 +
1.25 +struct nsArenaMemoryStats;
1.26 +
1.27 +class nsPresArena {
1.28 +public:
1.29 + nsPresArena();
1.30 + ~nsPresArena();
1.31 +
1.32 + enum ObjectID {
1.33 + nsLineBox_id = nsQueryFrame::NON_FRAME_MARKER,
1.34 + nsRuleNode_id,
1.35 + nsStyleContext_id,
1.36 + nsFrameList_id,
1.37 +
1.38 + /**
1.39 + * The PresArena implementation uses this bit to distinguish objects
1.40 + * allocated by size from objects allocated by type ID (that is, frames
1.41 + * using AllocateByFrameID and other objects using AllocateByObjectID).
1.42 + * It should not collide with any Object ID (above) or frame ID (in
1.43 + * nsQueryFrame.h). It is not 0x80000000 to avoid the question of
1.44 + * whether enumeration constants are signed.
1.45 + */
1.46 + NON_OBJECT_MARKER = 0x40000000
1.47 + };
1.48 +
1.49 + /**
1.50 + * Pool allocation with recycler lists indexed by object size, aSize.
1.51 + */
1.52 + NS_HIDDEN_(void*) AllocateBySize(size_t aSize)
1.53 + {
1.54 + return Allocate(uint32_t(aSize) | uint32_t(NON_OBJECT_MARKER), aSize);
1.55 + }
1.56 + NS_HIDDEN_(void) FreeBySize(size_t aSize, void* aPtr)
1.57 + {
1.58 + Free(uint32_t(aSize) | uint32_t(NON_OBJECT_MARKER), aPtr);
1.59 + }
1.60 +
1.61 + /**
1.62 + * Pool allocation with recycler lists indexed by frame-type ID.
1.63 + * Every aID must always be used with the same object size, aSize.
1.64 + */
1.65 + NS_HIDDEN_(void*) AllocateByFrameID(nsQueryFrame::FrameIID aID, size_t aSize)
1.66 + {
1.67 + return Allocate(aID, aSize);
1.68 + }
1.69 + NS_HIDDEN_(void) FreeByFrameID(nsQueryFrame::FrameIID aID, void* aPtr)
1.70 + {
1.71 + Free(aID, aPtr);
1.72 + }
1.73 +
1.74 + /**
1.75 + * Pool allocation with recycler lists indexed by object-type ID (see above).
1.76 + * Every aID must always be used with the same object size, aSize.
1.77 + */
1.78 + NS_HIDDEN_(void*) AllocateByObjectID(ObjectID aID, size_t aSize)
1.79 + {
1.80 + return Allocate(aID, aSize);
1.81 + }
1.82 + NS_HIDDEN_(void) FreeByObjectID(ObjectID aID, void* aPtr)
1.83 + {
1.84 + Free(aID, aPtr);
1.85 + }
1.86 +
1.87 + /**
1.88 + * Increment aArenaStats with sizes of interesting objects allocated in this
1.89 + * arena and its mOther field with the size of everything else.
1.90 + */
1.91 + void AddSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf,
1.92 + nsArenaMemoryStats* aArenaStats);
1.93 +
1.94 +private:
1.95 + NS_HIDDEN_(void*) Allocate(uint32_t aCode, size_t aSize);
1.96 + NS_HIDDEN_(void) Free(uint32_t aCode, void* aPtr);
1.97 +
1.98 + // All keys to this hash table fit in 32 bits (see below) so we do not
1.99 + // bother actually hashing them.
1.100 + class FreeList : public PLDHashEntryHdr
1.101 + {
1.102 + public:
1.103 + typedef uint32_t KeyType;
1.104 + nsTArray<void *> mEntries;
1.105 + size_t mEntrySize;
1.106 + size_t mEntriesEverAllocated;
1.107 +
1.108 + typedef const void* KeyTypePointer;
1.109 + KeyTypePointer mKey;
1.110 +
1.111 + FreeList(KeyTypePointer aKey)
1.112 + : mEntrySize(0), mEntriesEverAllocated(0), mKey(aKey) {}
1.113 + // Default copy constructor and destructor are ok.
1.114 +
1.115 + bool KeyEquals(KeyTypePointer const aKey) const
1.116 + { return mKey == aKey; }
1.117 +
1.118 + static KeyTypePointer KeyToPointer(KeyType aKey)
1.119 + { return NS_INT32_TO_PTR(aKey); }
1.120 +
1.121 + static PLDHashNumber HashKey(KeyTypePointer aKey)
1.122 + { return NS_PTR_TO_INT32(aKey); }
1.123 +
1.124 + enum { ALLOW_MEMMOVE = false };
1.125 + };
1.126 +
1.127 +#if defined(MOZ_HAVE_MEM_CHECKS)
1.128 + static PLDHashOperator UnpoisonFreeList(FreeList* aEntry, void*);
1.129 +#endif
1.130 + static PLDHashOperator FreeListEnumerator(FreeList* aEntry, void* aData);
1.131 + static size_t SizeOfFreeListEntryExcludingThis(FreeList* aEntry,
1.132 + mozilla::MallocSizeOf aMallocSizeOf,
1.133 + void*);
1.134 +
1.135 + nsTHashtable<FreeList> mFreeLists;
1.136 + PLArenaPool mPool;
1.137 +};
1.138 +
1.139 +#endif
