void LoopFinder::find_loop_exits(BlockBegin* bb, Loop* loop) {
BlockLoopInfo* bli = get_block_info(bb);
int loop_index = bb->loop_index();
// search all successors and locate the ones that do not have the same loop_index
BlockEnd* be = bb->end();
int n = be->number_of_sux() - 1;
for(; n >= 0; n--) {
BlockBegin* sux = be->sux_at(n);
BlockLoopInfo* sux_bli = get_block_info(sux);
if (sux->loop_index() != loop_index) {
loop->append_loop_exit(bb, sux);
}
}
}
void LIR_LocalCaching::cache_locals() {
LoopList* loops = ir()->loops();
BlockList* all_blocks = ir()->code();
WordSizeList* local_name_to_offset_map = ir()->local_name_to_offset_map();
if (loops == NULL) {
// collect global scan information
BlockListScanInfo gsi(ir()->code());
RegisterManager* global_scan_info = gsi.info();
// just cache registers globally.
LocalMappingSetter setter(cache_locals_for_blocks(all_blocks, global_scan_info));
all_blocks->iterate_forward(&setter);
} else {
assert(loops->length() != 0, "should be at least one loop");
int i;
// collect all the blocks that are outside of the loops
BlockList* non_loop_blocks = new BlockList;
for (i = 0; i < all_blocks->length(); i++) {
BlockBegin* b = all_blocks->at(i);
if (b->loop_index() == -1 && b->next()->as_CachingChange() == NULL) {
non_loop_blocks->append(b);
}
}
RegisterManager* global_scan_info = new RegisterManager();
// scan each of the loops and the remaining blocks recording register usage
// so we know what registers are free.
RegisterManagerArray scan_infos(loops->length() + 1);
for (i = 0; i < loops->length(); i++) {
Loop* loop = loops->at(i);
BlockListScanInfo lsi(loop->blocks());
scan_infos.at_put(i, lsi.info());
// accumulate the global state
global_scan_info->merge(lsi.info());
}
BlockListScanInfo lsi(non_loop_blocks);
scan_infos.at_put(loops->length(), lsi.info());
// accumulate the global state
global_scan_info->merge(lsi.info());
// use the global mapping as a guide in the rest of the register selection process.
LocalMapping* global = cache_locals_for_blocks(all_blocks, global_scan_info, true);
LocalMapping* pref = new LocalMapping(local_name_to_offset_map);
pref->merge(global);
pref->merge(_preferred);
_preferred = pref;
for (i = 0; i < loops->length(); i++) {
if (i < LIRCacheLoopStart || (uint)i >= (uint)LIRCacheLoopStop) {
continue;
}
Loop* loop = loops->at(i);
LocalMapping* mapping = cache_locals_for_blocks(loop->blocks(), scan_infos.at(i));
LocalMappingSetter setter(mapping);
loop->blocks()->iterate_forward(&setter);
_preferred->merge(mapping);
mapping->join(global);
}
LocalMapping* mapping = cache_locals_for_blocks(non_loop_blocks, scan_infos.at(loops->length()));
mapping->join(global);
LocalMappingSetter setter(mapping);
non_loop_blocks->iterate_forward(&setter);
}
}
