/*
* delete_freenode - delete the block from free list when it is allocated
*/
static void delete_freenode(void *bp)
{
void *next_free_block_addr = (void *)*NEXTP(bp);
void *prev_free_block_addr = (void *)*PREVP(bp);
PUT_ADDR(NEXTP(prev_free_block_addr), next_free_block_addr);
if (next_free_block_addr != NULL) {
PUT_ADDR(PREVP(next_free_block_addr), prev_free_block_addr);
}
}
/*
* insert_freenode - insert the freed block to the free list
*/
static void insert_freenode(void *bp)
{
size_t size = GET_SIZE(HDRP(bp));
void *root = getroot(getclass(size));
void *next_free_block_addr = (void *)*NEXTP(root);
PUT_ADDR(NEXTP(bp), *NEXTP(root));
PUT_ADDR(PREVP(bp), root);
PUT_ADDR(NEXTP(root), bp);
if (next_free_block_addr != NULL) {
PUT_ADDR(PREVP(next_free_block_addr), bp);
}
}
/*
* insert_freenode - insert the freed block to the free list
*/
inline void insert_freenode(void *bp)
{
size_t size = GET_SIZE(HDRP(bp));
void *root = getroot(getclass(size));
void *nextp = next_free_blck(root);
void *prevp = root;
for (; nextp!=NULL && GET_SIZE(HDRP(nextp)) < size; prevp = nextp, nextp = (char *)next_free_blck(nextp)) {
}
PUT_ADDR(NEXTP(bp), nextp);
PUT_ADDR(PREVP(bp), prevp);
PUT_ADDR(NEXTP(prevp), bp);
if (nextp != NULL) {
PUT_ADDR(PREVP(nextp), bp);
}
}
/**********************************************************
* insert_freelist
* Place the free block ptr bp on the appropriated
* segregated free list
* Insert at the first element of the list
**********************************************************/
void insert_freelist(intptr_t * bp) {
// Find out which list should the free block insert to
int index = size_to_index(GET_SIZE(HDRP(bp)));
// Head of the list
intptr_t * listp = seg_free_list[index];
// Set the prev_ptr and next_ptr of the current block
PUT(bp, GET(seg_free_list[index])); // next
PUTP(PREVP(bp), listp); // prev
// If the list previously has elements inside
if (GET(listp) != 0) {
// Set the next element to point to the current bp
PUTP(PREVP(*listp), bp);
}
//Set head to point to the current bp
PUTP(listp, bp);
}
/**********************************************************
* delete_from_list
* Place the free block ptr bp on the appropriated
* segregated free list
* Insert at the first element of the list
**********************************************************/
void delete_from_list(void *bp) {
// If the block is allocated, cannot be freed
if (GET_ALLOC(HDRP(bp))) {
return;
}
// If it does not have next element
if (*(char*) bp == 0) {
// Set previous block ptr in the previous element to 0
PUT(PREVB(bp), 0);
} else { // If it has next element
// Set next block ptr in the prev element to current's next element
PUTP(PREVB(bp), NEXTB(bp));
// Set prev block ptr in the next element to current's prev element
PUTP(PREVP(NEXTB(bp)), PREVB(bp));
}
}
