On Thu, Feb 27, 2025 at 03:32:32PM -0800, Junio C Hamano wrote: > Taylor Blau <me@xxxxxxxxxxxx> writes: > > > It looks like the aim here is to introduce a function which executes a > > callback for each object of some type in a bitmap. That's a thin wrapper > > over the ewah_iterator, but it's not clear why we need a wrapper around > > that function since it is internal to pack-bitmap.c. Likewise, this is a > > performance critical area, so I am not sure I'm in favor of adding a > > function pointer to a hot path which executes once per object for some > > object type. > > It internally introduced ewah_for_type(), giving the "struct > bitmap_index" object an abstraction that callers can ask for the > bitmap for any type the caller wants. Before the <type>_all bitmaps > were introduced, there were one ewah-bitmap per type, so it made > sense for a caller to ask "Now, for this bitmap_index, give me the > ewah-bitmap for commits", but with "commits_all" added to the > bitmap_index object, it is no longer clear to me what the answer to > that question should be. I think these are orthogonal. (FWIW, I think the correct answer would be "commits_all" in that world, but that is definitely out of scope for Patrick's immediate concern). In any event, I see that later on in the series it is important for callers to enumerate bitmapped objects of a certain type. So having a callback to do that makes sense. Thanks, Taylor
