void lspace_sweep(Lspace* lspace)
{
TRACE2("gc.process", "GC: lspace sweep algo start ...\n");
#ifdef GC_GEN_STATS
GC_Gen_Stats* stats = ((GC_Gen*)lspace->gc)->stats;
gc_gen_stats_set_los_collected_flag((GC_Gen*)lspace->gc, true);
#endif
unsigned int mark_bit_idx = 0;
POINTER_SIZE_INT cur_size = 0;
void *cur_area_start, *cur_area_end;
free_area_pool_reset(lspace->free_pool);
Partial_Reveal_Object* p_prev_obj = (Partial_Reveal_Object *)lspace->heap_start;
Partial_Reveal_Object* p_next_obj = lspace_get_first_marked_object_by_oi(lspace, &mark_bit_idx);
if(p_next_obj){
// obj_unmark_in_vt(p_next_obj);
/*Fixme: This might not be necessary, for there is a bit clearing operation in forward_object->obj_mark_in_oi*/
obj_clear_dual_bits_in_oi(p_next_obj);
/*For_statistic: sum up the size of suvived large objects, useful to deciede los extention.*/
unsigned int obj_size = vm_object_size(p_next_obj);
#ifdef USE_32BITS_HASHCODE
obj_size += (hashcode_is_attached(p_next_obj))?GC_OBJECT_ALIGNMENT:0;
#endif
lspace->last_surviving_size += ALIGN_UP_TO_KILO(obj_size);
#ifdef GC_GEN_STATS
stats->los_suviving_obj_num++;
stats->los_suviving_obj_size += obj_size;
#endif
}
cur_area_start = (void*)ALIGN_UP_TO_KILO(p_prev_obj);
cur_area_end = (void*)ALIGN_DOWN_TO_KILO(p_next_obj);
unsigned int hash_extend_size = 0;
Free_Area* cur_area = NULL;
while(cur_area_end){
cur_area = NULL;
cur_size = (POINTER_SIZE_INT)cur_area_end - (POINTER_SIZE_INT)cur_area_start;
if(cur_size){
//debug
assert(cur_size >= KB);
cur_area = free_area_new(cur_area_start, cur_size);
if( cur_area ) free_pool_add_area(lspace->free_pool, cur_area);
}
/* successfully create an area */
p_prev_obj = p_next_obj;
p_next_obj = lspace_get_next_marked_object_by_oi(lspace, &mark_bit_idx);
if(p_next_obj){
// obj_unmark_in_vt(p_next_obj);
obj_clear_dual_bits_in_oi(p_next_obj);
/*For_statistic: sum up the size of suvived large objects, useful to deciede los extention.*/
unsigned int obj_size = vm_object_size(p_next_obj);
#ifdef USE_32BITS_HASHCODE
obj_size += (hashcode_is_attached(p_next_obj))?GC_OBJECT_ALIGNMENT:0;
#endif
lspace->last_surviving_size += ALIGN_UP_TO_KILO(obj_size);
#ifdef GC_GEN_STATS
stats->los_suviving_obj_num++;
stats->los_suviving_obj_size += obj_size;
#endif
}
#ifdef USE_32BITS_HASHCODE
hash_extend_size = (hashcode_is_attached((Partial_Reveal_Object*)p_prev_obj))?GC_OBJECT_ALIGNMENT:0;
#endif
cur_area_start = (void*)ALIGN_UP_TO_KILO((POINTER_SIZE_INT)p_prev_obj + vm_object_size(p_prev_obj) + hash_extend_size);
cur_area_end = (void*)ALIGN_DOWN_TO_KILO(p_next_obj);
}
/* cur_area_end == NULL */
cur_area_end = (void*)ALIGN_DOWN_TO_KILO(lspace->heap_end);
cur_size = (POINTER_SIZE_INT)cur_area_end - (POINTER_SIZE_INT)cur_area_start;
if(cur_size){
//debug
assert(cur_size >= KB);
cur_area = free_area_new(cur_area_start, cur_size);
if( cur_area ) free_pool_add_area(lspace->free_pool, cur_area);
}
mark_bit_idx = 0;
assert(!lspace_get_first_marked_object(lspace, &mark_bit_idx));
TRACE2("gc.process", "GC: end of lspace sweep algo ...\n");
return;
}
static void mspace_move_objects(Collector* collector, Mspace* mspace)
{
Block_Header* curr_block = collector->cur_compact_block;
Block_Header* dest_block = collector->cur_target_block;
Block_Header *local_last_dest = dest_block;
void* dest_sector_addr = dest_block->base;
Boolean is_fallback = collect_is_fallback();
#ifdef USE_32BITS_HASHCODE
Hashcode_Buf* old_hashcode_buf = NULL;
Hashcode_Buf* new_hashcode_buf = hashcode_buf_create();
hashcode_buf_init(new_hashcode_buf);
#endif
#ifdef GC_GEN_STATS
GC_Gen_Collector_Stats* stats = (GC_Gen_Collector_Stats*)collector->stats;
#endif
unsigned int debug_num_live_obj = 0;
while( curr_block ){
if(verify_live_heap){
atomic_inc32(&debug_num_compact_blocks);
debug_num_live_obj = 0;
}
void* start_pos;
Partial_Reveal_Object* p_obj = block_get_first_marked_object(curr_block, &start_pos);
if( !p_obj ){
#ifdef USE_32BITS_HASHCODE
hashcode_buf_clear(curr_block->hashcode_buf);
#endif
assert(!verify_live_heap ||debug_num_live_obj == curr_block->num_live_objs);
curr_block = mspace_get_next_compact_block(collector, mspace);
continue;
}
int curr_sector = OBJECT_INDEX_TO_OFFSET_TABLE(p_obj);
void* src_sector_addr = p_obj;
while( p_obj ){
debug_num_live_obj++;
assert( obj_is_marked_in_vt(p_obj));
/* we don't check if it's set, since only non-forwarded objs from last NOS partial-forward collection need it. */
obj_clear_dual_bits_in_oi(p_obj);
#ifdef GC_GEN_STATS
gc_gen_collector_update_moved_nos_mos_obj_stats_major(stats, vm_object_size(p_obj));
#endif
#ifdef USE_32BITS_HASHCODE
move_compact_process_hashcode(p_obj, curr_block->hashcode_buf, new_hashcode_buf);
#endif
POINTER_SIZE_INT curr_sector_size = (POINTER_SIZE_INT)start_pos - (POINTER_SIZE_INT)src_sector_addr;
/* check if dest block is not enough to hold this sector. If yes, grab next one */
POINTER_SIZE_INT block_end = (POINTER_SIZE_INT)GC_BLOCK_END(dest_block);
if( ((POINTER_SIZE_INT)dest_sector_addr + curr_sector_size) > block_end ){
dest_block->new_free = dest_sector_addr;
#ifdef USE_32BITS_HASHCODE
block_swap_hashcode_buf(dest_block, &new_hashcode_buf, &old_hashcode_buf);
#endif
dest_block = mspace_get_next_target_block(collector, mspace);
if(dest_block == NULL){
#ifdef USE_32BITS_HASHCODE
hashcode_buf_rollback_new_entry(old_hashcode_buf);
#endif
collector->result = FALSE;
return;
}
#ifdef USE_32BITS_HASHCODE
hashcode_buf_transfer_new_entry(old_hashcode_buf, new_hashcode_buf);
#endif
if((!local_last_dest) || (dest_block->block_idx > local_last_dest->block_idx))
local_last_dest = dest_block;
block_end = (POINTER_SIZE_INT)GC_BLOCK_END(dest_block);
dest_sector_addr = dest_block->base;
}
assert(((POINTER_SIZE_INT)dest_sector_addr + curr_sector_size) <= block_end );
Partial_Reveal_Object *last_obj_end = (Partial_Reveal_Object *)start_pos;
/* check if next live object is out of current sector. If not, loop back to continue within this sector. FIXME:: we should add a condition for block check (?) */
p_obj = block_get_next_marked_object(curr_block, &start_pos);
if ((p_obj != NULL) && (OBJECT_INDEX_TO_OFFSET_TABLE(p_obj) == curr_sector)) {
if(last_obj_end != p_obj) obj_set_vt_to_next_obj(last_obj_end, p_obj);
continue;
}
/* current sector is done, let's move it. */
POINTER_SIZE_INT sector_distance = (POINTER_SIZE_INT)src_sector_addr - (POINTER_SIZE_INT)dest_sector_addr;
assert((sector_distance % GC_OBJECT_ALIGNMENT) == 0);
/* if sector_distance is zero, we don't do anything. But since block offset table is never cleaned, we have to set 0 to it. */
curr_block->table[curr_sector] = sector_distance;
if(sector_distance != 0)
memmove(dest_sector_addr, src_sector_addr, curr_sector_size);
#ifdef USE_32BITS_HASHCODE
hashcode_buf_refresh_new_entry(new_hashcode_buf, sector_distance);
#endif
dest_sector_addr = (void*)((POINTER_SIZE_INT)dest_sector_addr + curr_sector_size);
src_sector_addr = p_obj;
curr_sector = OBJECT_INDEX_TO_OFFSET_TABLE(p_obj);
}
#ifdef USE_32BITS_HASHCODE
hashcode_buf_clear(curr_block->hashcode_buf);
#endif
assert(!verify_live_heap ||debug_num_live_obj == curr_block->num_live_objs);
curr_block = mspace_get_next_compact_block(collector, mspace);
}
dest_block->new_free = dest_sector_addr;
collector->cur_target_block = local_last_dest;
#ifdef USE_32BITS_HASHCODE
old_hashcode_buf = block_set_hashcode_buf(dest_block, new_hashcode_buf);
hashcode_buf_destory(old_hashcode_buf);
#endif
return;
}
