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Moved block functionality into functions

main
Titouan Rigoudy 11 years ago
parent
commit
d62589cb60
1 changed files with 27 additions and 22 deletions
  1. +27
    -22
      yamalloc.c

+ 27
- 22
yamalloc.c View File

@ -63,6 +63,23 @@ void ya_print_blocks() {
}
#endif
void block_init(intptr_t *block, intptr_t size) {
block[-1] = size;
block[size - 2] = size;
}
void block_alloc(intptr_t *block) {
intptr_t block_size = YA_SZ_BLK(block);
block[-1] |= 1;
block[block_size-2] |= 1;
}
void block_free(intptr_t *block) {
intptr_t block_size = YA_SZ_BLK(block);
block[-1] &= -2;
block[block_size-2] &= -2;
}
intptr_t *block_join_prev(intptr_t *block) {
intptr_t prev_size = YA_SZ_TAG(block[-2]);
intptr_t *prev = block - prev_size;
@ -70,11 +87,9 @@ intptr_t *block_join_prev(intptr_t *block) {
return block;
}
intptr_t block_size = YA_SZ_BLK(block);
intptr_t size = prev_size + block_size;
prev[-1] = size;
block[block_size - 2] = size;
block_init(prev, prev_size + block_size);
ya_debug("block_join_prev: joining %p:%ld and %p:%ld -> %p:%ld\n",
block, block_size, prev, prev_size, prev, size);
block, block_size, prev, prev_size, prev, prev_size + block_size);
return prev;
}
@ -85,11 +100,9 @@ intptr_t *block_join_next(intptr_t *block) {
return block;
}
intptr_t next_size = YA_SZ_BLK(next);
intptr_t size = next_size + block_size;
block[-1] = size;
next[next_size - 2] = size;
block_init(block, block_size + next_size);
ya_debug("block_join_next: joining %p:%ld and %p:%ld -> %p:%ld\n",
block, block_size, next, next_size, block, size);
block, block_size, next, next_size, block, block_size + next_size);
return block;
}
@ -101,11 +114,8 @@ intptr_t *block_join(intptr_t *block) {
}
void block_split(intptr_t *block, intptr_t size) {
intptr_t old_size = YA_SZ_BLK(block);
block[-1] = size;
block[size - 2] = size;
block[size - 1] = old_size - size;
block[old_size - 2] = old_size - size;
block_init(block + size, YA_SZ_BLK(block) - size);
block_init(block, size);
}
intptr_t *block_find(intptr_t size) {
@ -132,8 +142,7 @@ intptr_t *heap_init() {
heap_start = ptr; // cast to intptr_t *
heap_start += 2; // space for the first block[-1] + dword alignment
heap_end = heap_start + size_w;
heap_start[-1] = size_w;
heap_end[-2] = size_w;
block_init(heap_start, size_w);
ya_debug("heap_init: start = %p, end = %p, size_w = %ld\n",
heap_start, heap_end, size_w);
return heap_start;
@ -149,8 +158,7 @@ intptr_t *heap_extend(intptr_t size_w) {
}
intptr_t *block = ptr; // == old heap_end
heap_end = block + size_w;
block[-1] = size_w;
heap_end[-2] = size_w;
block_init(block, size_w);
ya_debug("heap_extend: old end = %p, new end = %p, size_w = %ld\n",
block, heap_end, size_w);
ya_print_blocks();
@ -175,8 +183,7 @@ void *malloc(size_t size) {
if (size_w < block_size) {
block_split(block, size_w);
}
block[-1] |= 1;
block[block_size - 2] |= 1;
block_alloc(block);
return block;
}
@ -185,8 +192,6 @@ void free(void *ptr) {
if (block < heap_start || block > heap_end || !YA_IS_ALLOC_BLK(block)) {
return; // TODO: provoke segfault
}
intptr_t block_size = YA_SZ_BLK(block);
block[-1] &= -2; // erase allocated bit
block[block_size - 2] &= -2;
block_free(block);
block_join(block);
}

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