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TINSEL: Fix handling of free memory blocks

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svn-id: r45416
This commit is contained in:
Max Horn 2009-10-26 20:35:06 +00:00
parent 692a4b74dc
commit e1de772e72
1 changed files with 17 additions and 17 deletions
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34
engines/tinsel/heapmem.cpp
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@ -32,6 +32,7 @@ namespace Tinsel {
// internal allocation flags
#define DWM_USED 0x0001 ///< the objects memory block is in use
#define DWM_DISCARDED 0x0100 ///< the objects memory block has been discarded
#define DWM_LOCKED 0x0200 ///< the objects memory block is locked
#define DWM_SENTINEL 0x0400 ///< the objects memory block is a sentinel
@ -185,9 +186,6 @@ bool HeapCompact(long size, bool bDiscard) {
for (pPrev = pHeap->pNext, pCur = pPrev->pNext;
pCur != pHeap; pPrev = pCur, pCur = pCur->pNext) {
if (pPrev->flags == 0 && pCur->flags == 0) {
// set the changed flag
bChanged = true;
// both blocks are free - merge them
pPrev->size += pCur->size;
@ -198,18 +196,19 @@ bool HeapCompact(long size, bool bDiscard) {
// free the current mnode
FreeMemNode(pCur);
// set the changed flag
bChanged = true;
// leave the loop
break;
} else if ((pPrev->flags & (DWM_LOCKED | DWM_DISCARDED)) == 0
&& pCur->flags == 0) {
// a free block after a moveable block - swap them
} else if (pPrev->flags == DWM_USED && pCur->flags == 0) {
// a free block after a moveable, non-discarded, not locked block - swap them
// set the changed flag
bChanged = true;
// move the unlocked blocks data up (can overlap)
memmove(pPrev->pBaseAddr + pCur->size,
pPrev->pBaseAddr, pPrev->size);
memmove(pPrev->pBaseAddr + pCur->size, pPrev->pBaseAddr, pPrev->size);
// swap the order in the linked list
pPrev->pPrev->pNext = pCur;
@ -248,7 +247,7 @@ bool HeapCompact(long size, bool bDiscard) {
oldest = DwGetCurrentTime();
pOldest = NULL;
for (pCur = pHeap->pNext; pCur != pHeap; pCur = pCur->pNext) {
if ((pCur->flags & (DWM_DISCARDED | DWM_LOCKED)) == 0) {
if (pCur->flags == DWM_USED) {
// found a non-discarded discardable block
if (pCur->lruTime < oldest) {
oldest = pCur->lruTime;
@ -271,7 +270,7 @@ bool HeapCompact(long size, bool bDiscard) {
* @param flags Allocation attributes
* @param size Number of bytes to allocate
*/
static MEM_NODE *MemoryAlloc(int flags, long size) {
static MEM_NODE *MemoryAlloc(long size) {
const MEM_NODE *pHeap = &heapSentinel;
MEM_NODE *pNode;
@ -286,7 +285,7 @@ static MEM_NODE *MemoryAlloc(int flags, long size) {
for (pNode = pHeap->pNext; pNode != pHeap; pNode = pNode->pNext) {
if (pNode->flags == 0 && pNode->size >= size) {
// a free block of the required size
pNode->flags = flags;
pNode->flags = DWM_USED;
// update the LRU time
pNode->lruTime = DwGetCurrentTime() + 1;
@ -335,7 +334,7 @@ MEM_NODE *MemoryNoAlloc() {
// chain a discarded node onto the end of the heap
MEM_NODE *pNode = AllocMemNode();
pNode->flags = DWM_DISCARDED;
pNode->flags = DWM_USED | DWM_DISCARDED;
// set mnode at the end of the list
pNode->pPrev = pHeap->pPrev;
@ -374,9 +373,10 @@ void MemoryDiscard(MEM_NODE *pMemNode) {
// validate mnode pointer
assert(pMemNode >= mnodeList && pMemNode <= mnodeList + NUM_MNODES - 1);
// object cannot be locked
assert((pMemNode->flags & DWM_LOCKED) == 0);
// object must be in use and locked
assert((pMemNode->flags & (DWM_USED | DWM_LOCKED)) == DWM_USED);
// discard it if it isn't already
if ((pMemNode->flags & DWM_DISCARDED) == 0) {
// allocate a free node to replace this node
MEM_NODE *pTemp = AllocMemNode();
@ -452,8 +452,8 @@ void MemoryReAlloc(MEM_NODE *pMemNode, long size) {
assert(size);
if (size != pMemNode->size) {
// make sure memory object is not locked and discarded
assert(!(pMemNode->flags & DWM_LOCKED) && (pMemNode->flags & DWM_DISCARDED));
// make sure memory object is discarded and not locked
assert(pMemNode->flags == DWM_USED | DWM_DISCARDED);
assert(pMemNode->size == 0);
// unlink the mnode from the current heap
@ -461,7 +461,7 @@ void MemoryReAlloc(MEM_NODE *pMemNode, long size) {
pMemNode->pPrev->pNext = pMemNode->pNext;
// allocate a new node
pNew = MemoryAlloc(pMemNode->flags & ~DWM_DISCARDED, size);
pNew = MemoryAlloc(size);
// make sure memory allocated
assert(pNew != NULL);