michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * vim: set ts=2 sw=2 et tw=78:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
michael@0:  */
michael@0: 
michael@0: /* arena allocation for the frame tree and closely-related objects */
michael@0: 
michael@0: #ifndef nsPresArena_h___
michael@0: #define nsPresArena_h___
michael@0: 
michael@0: #include "mozilla/MemoryChecking.h" // Note: Do not remove this, needed for MOZ_HAVE_MEM_CHECKS below
michael@0: #include "mozilla/MemoryReporting.h"
michael@0: #include <stdint.h>
michael@0: #include "nscore.h"
michael@0: #include "nsQueryFrame.h"
michael@0: #include "nsTArray.h"
michael@0: #include "nsTHashtable.h"
michael@0: #include "plarena.h"
michael@0: 
michael@0: struct nsArenaMemoryStats;
michael@0: 
michael@0: class nsPresArena {
michael@0: public:
michael@0:   nsPresArena();
michael@0:   ~nsPresArena();
michael@0: 
michael@0:   enum ObjectID {
michael@0:     nsLineBox_id = nsQueryFrame::NON_FRAME_MARKER,
michael@0:     nsRuleNode_id,
michael@0:     nsStyleContext_id,
michael@0:     nsFrameList_id,
michael@0: 
michael@0:     /**
michael@0:      * The PresArena implementation uses this bit to distinguish objects
michael@0:      * allocated by size from objects allocated by type ID (that is, frames
michael@0:      * using AllocateByFrameID and other objects using AllocateByObjectID).
michael@0:      * It should not collide with any Object ID (above) or frame ID (in
michael@0:      * nsQueryFrame.h).  It is not 0x80000000 to avoid the question of
michael@0:      * whether enumeration constants are signed.
michael@0:      */
michael@0:     NON_OBJECT_MARKER = 0x40000000
michael@0:   };
michael@0: 
michael@0:   /**
michael@0:    * Pool allocation with recycler lists indexed by object size, aSize.
michael@0:    */
michael@0:   NS_HIDDEN_(void*) AllocateBySize(size_t aSize)
michael@0:   {
michael@0:     return Allocate(uint32_t(aSize) | uint32_t(NON_OBJECT_MARKER), aSize);
michael@0:   }
michael@0:   NS_HIDDEN_(void) FreeBySize(size_t aSize, void* aPtr)
michael@0:   {
michael@0:     Free(uint32_t(aSize) | uint32_t(NON_OBJECT_MARKER), aPtr);
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Pool allocation with recycler lists indexed by frame-type ID.
michael@0:    * Every aID must always be used with the same object size, aSize.
michael@0:    */
michael@0:   NS_HIDDEN_(void*) AllocateByFrameID(nsQueryFrame::FrameIID aID, size_t aSize)
michael@0:   {
michael@0:     return Allocate(aID, aSize);
michael@0:   }
michael@0:   NS_HIDDEN_(void) FreeByFrameID(nsQueryFrame::FrameIID aID, void* aPtr)
michael@0:   {
michael@0:     Free(aID, aPtr);
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Pool allocation with recycler lists indexed by object-type ID (see above).
michael@0:    * Every aID must always be used with the same object size, aSize.
michael@0:    */
michael@0:   NS_HIDDEN_(void*) AllocateByObjectID(ObjectID aID, size_t aSize)
michael@0:   {
michael@0:     return Allocate(aID, aSize);
michael@0:   }
michael@0:   NS_HIDDEN_(void) FreeByObjectID(ObjectID aID, void* aPtr)
michael@0:   {
michael@0:     Free(aID, aPtr);
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Increment aArenaStats with sizes of interesting objects allocated in this
michael@0:    * arena and its mOther field with the size of everything else.
michael@0:    */
michael@0:   void AddSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf,
michael@0:                               nsArenaMemoryStats* aArenaStats);
michael@0: 
michael@0: private:
michael@0:   NS_HIDDEN_(void*) Allocate(uint32_t aCode, size_t aSize);
michael@0:   NS_HIDDEN_(void) Free(uint32_t aCode, void* aPtr);
michael@0: 
michael@0:   // All keys to this hash table fit in 32 bits (see below) so we do not
michael@0:   // bother actually hashing them.
michael@0:   class FreeList : public PLDHashEntryHdr
michael@0:   {
michael@0:   public:
michael@0:     typedef uint32_t KeyType;
michael@0:     nsTArray<void *> mEntries;
michael@0:     size_t mEntrySize;
michael@0:     size_t mEntriesEverAllocated;
michael@0: 
michael@0:     typedef const void* KeyTypePointer;
michael@0:     KeyTypePointer mKey;
michael@0: 
michael@0:     FreeList(KeyTypePointer aKey)
michael@0:     : mEntrySize(0), mEntriesEverAllocated(0), mKey(aKey) {}
michael@0:     // Default copy constructor and destructor are ok.
michael@0: 
michael@0:     bool KeyEquals(KeyTypePointer const aKey) const
michael@0:     { return mKey == aKey; }
michael@0: 
michael@0:     static KeyTypePointer KeyToPointer(KeyType aKey)
michael@0:     { return NS_INT32_TO_PTR(aKey); }
michael@0: 
michael@0:     static PLDHashNumber HashKey(KeyTypePointer aKey)
michael@0:     { return NS_PTR_TO_INT32(aKey); }
michael@0: 
michael@0:     enum { ALLOW_MEMMOVE = false };
michael@0:   };
michael@0: 
michael@0: #if defined(MOZ_HAVE_MEM_CHECKS)
michael@0:   static PLDHashOperator UnpoisonFreeList(FreeList* aEntry, void*);
michael@0: #endif
michael@0:   static PLDHashOperator FreeListEnumerator(FreeList* aEntry, void* aData);
michael@0:   static size_t SizeOfFreeListEntryExcludingThis(FreeList* aEntry,
michael@0:                                                  mozilla::MallocSizeOf aMallocSizeOf,
michael@0:                                                  void*);
michael@0: 
michael@0:   nsTHashtable<FreeList> mFreeLists;
michael@0:   PLArenaPool mPool;
michael@0: };
michael@0: 
michael@0: #endif