void try_merge_buddy_recursive( ChunkMap::iterator cmit ) {
// compute address of buddy
intptr_t address = cmit->second.address;
intptr_t buddy_address = (address ^ cmit->second.size);
DVLOG(5) << cmit->second << " buddy address " << (void *) buddy_address;
// does it exist?
ChunkMap::iterator buddy_iterator = chunks_.find( buddy_address );
if( buddy_iterator != chunks_.end() &&
buddy_iterator->second.size == cmit->second.size &&
buddy_iterator->second.in_use == false ) {
DVLOG(5) << "buddy found! address " << (void *) address << " buddy address " << (void *) buddy_address;
// remove the higher-addressed chunk
ChunkMap::iterator higher_iterator = address < buddy_address ? buddy_iterator : cmit;
remove_from_free_list( higher_iterator );
chunks_.erase( higher_iterator );
// keep the the lower-addressed chunk in the map:
// update its size and move it to the right free list
ChunkMap::iterator lower_iterator = address < buddy_address ? cmit : buddy_iterator;
remove_from_free_list( lower_iterator ); // should these be swapped? I think so.
lower_iterator->second.size *= 2;
add_to_free_list( lower_iterator );
// see if we have more to merge
try_merge_buddy_recursive( lower_iterator );
}
}
