Commit fd8b6bcf authored by Damien's avatar Damien
Browse files

Add gc_free function to force a block to be freed.

parent 7b2d3f38
......@@ -52,7 +52,6 @@ void gc_init(void *start, void *end) {
printf(" alloc table at %p, length %u bytes\n", gc_alloc_table_start, gc_alloc_table_byte_len);
printf(" pool at %p, length %u blocks = %u words = %u bytes\n", gc_pool_start, gc_pool_block_len, gc_pool_word_len, gc_pool_word_len * BYTES_PER_WORD);
*/
printf("GC: %u bytes\n", gc_pool_word_len * BYTES_PER_WORD);
}
// ATB = allocation table byte
......@@ -89,13 +88,15 @@ void gc_init(void *start, void *end) {
#define PTR_FROM_BLOCK(block) (((block) * BYTES_PER_BLOCK + (machine_uint_t)gc_pool_start))
#define ATB_FROM_BLOCK(bl) ((bl) / BLOCKS_PER_ATB)
#define VERIFY_PTR(ptr) ( \
(ptr & (BYTES_PER_BLOCK - 1)) == 0 /* must be aligned on a block */ \
&& ptr >= (machine_uint_t)gc_pool_start /* must be above start of pool */ \
&& ptr < (machine_uint_t)gc_pool_end /* must be below end of pool */ \
)
#define VERIFY_MARK_AND_PUSH(ptr) \
do { \
if ( \
(ptr & (BYTES_PER_BLOCK - 1)) == 0 /* must be aligned on a block */ \
&& ptr >= (machine_uint_t)gc_pool_start /* must be above start of pool */ \
&& ptr < (machine_uint_t)gc_pool_end /* must be below end of pool */ \
) { \
if (VERIFY_PTR(ptr)) { \
machine_uint_t _block = BLOCK_FROM_PTR(ptr); \
if (ATB_GET_KIND(_block) == AT_HEAD) { \
/* an unmarked head, mark it, and push it on gc stack */ \
......@@ -283,14 +284,26 @@ found:
return (void*)(gc_pool_start + start_block * WORDS_PER_BLOCK);
}
// force the freeing of a piece of memory
void gc_free(void *ptr_in) {
machine_uint_t ptr = (machine_uint_t)ptr_in;
if (VERIFY_PTR(ptr)) {
machine_uint_t block = BLOCK_FROM_PTR(ptr);
if (ATB_GET_KIND(block) == AT_HEAD) {
// free head and all of its tail blocks
do {
ATB_ANY_TO_FREE(block);
block += 1;
} while (ATB_GET_KIND(block) == AT_TAIL);
}
}
}
machine_uint_t gc_nbytes(void *ptr_in) {
machine_uint_t ptr = (machine_uint_t)ptr_in;
if (
(ptr & (BYTES_PER_BLOCK - 1)) == 0 // must be aligned on a block
&& ptr >= (machine_uint_t)gc_pool_start // must be above start of pool
&& ptr < (machine_uint_t)gc_pool_end // must be below end of pool
) {
if (VERIFY_PTR(ptr)) {
machine_uint_t block = BLOCK_FROM_PTR(ptr);
if (ATB_GET_KIND(block) == AT_HEAD) {
// work out number of consecutive blocks in the chain starting with this on
......
......@@ -4,7 +4,8 @@ void gc_collect_root(void **ptrs, machine_uint_t len);
void gc_collect_end();
void gc_collect();
void *gc_alloc(machine_uint_t n_bytes);
machine_uint_t gc_nbytes(void *ptr_in);
void gc_free(void *ptr);
machine_uint_t gc_nbytes(void *ptr);
void *gc_realloc(void *ptr, machine_uint_t n_bytes);
typedef struct _gc_info_t {
......
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