void removeFromFreeList( heapAllocator* heap, block* b ) {
//validateFreeList( heap );
block* const pFree = prevFree( b );
block* const nFree = nextFree( b );
//printf( "prev: " xPTRf ", next: " xPTRf "\n", (uintptr_t)pFree, (uintptr_t)nFree );
//vAssert( nFree || pFree );
if ( pFree ) {
vAssert( pFree->free );
//vAssert( nFree || pFree->prevFree );
setNextFree( pFree, nFree );
}
else {
vAssert( heap->free == b );
if (!nFree ) {
block* bl = heap->first;
while (bl) {
vAssert( bl == b || !bl->free );
bl = bl->next;
}
}
heap->free = nFree;
}
if ( nFree ) {
vAssert( nFree->free );
setPrevFree( nFree, pFree );
}
setNextFree( b, NULL );
setPrevFree( b, NULL );
b->free = false;
//validateFreeList( heap );
b->free = true;
}
void addToFreeList( heapAllocator* heap, block* b ) {
b->free = true;
block* oldFree = heap->free;
vAssert( oldFree != b );
setNextFree( b, oldFree );
vAssert( oldFree != b );
vAssert( oldFree == NULL || prevFree( oldFree ) == NULL ); // It should have been first in the list
setPrevFree( oldFree, b );
heap->free = b;
setPrevFree( b, NULL );
}
/* coalesce free blocks */
static void *coalesce(void *bp){
size_t prevAllocBit = getPrevAlloc(getHeader(bp));
size_t nextAllocBit = getAlloc(getHeader(nextBlock(bp)));
size_t size = getSize(getHeader(bp));
size_t index;
size_t prevPAlloc;
/* both the previous and next block allocated */
if (prevAllocBit && nextAllocBit) {
setPrevFree(getHeader(nextBlock(bp)));
}
/* Only previous block is free */
else if (!prevAllocBit && nextAllocBit) {
size += getSize(getHeader(prevBlock(bp)));
prevPAlloc = getPrevAlloc(getHeader(prevBlock(bp)));
deleteListNode(prevBlock(bp));
put(getFooter(bp), size);
bp = prevBlock(bp);
put(getHeader(bp), pack(size, prevPAlloc, 0));
setPrevFree(getHeader(nextBlock(bp)));
}
/* Only next block is free */
else if (prevAllocBit && !nextAllocBit) {
size += getSize(getHeader(nextBlock(bp)));
deleteListNode(nextBlock(bp));
put(getHeader(bp), pack(size, prevAllocBit, 0));
put(getFooter(bp), size);
}
/* Both previous and next block are free */
else {
size += getSize(getHeader(prevBlock(bp))) +
getSize(getFooter(nextBlock(bp)));
prevPAlloc = getPrevAlloc(getHeader(prevBlock(bp)));
deleteListNode(nextBlock(bp));
deleteListNode(prevBlock(bp));
put(getHeader(prevBlock(bp)), pack(size, prevPAlloc, 0));
put(getFooter(nextBlock(bp)), size);
bp = prevBlock(bp);
}
index = getIndex(size);
insertListNode(bp, index);
return bp;
}
