Auto merge of #97863 - JakobDegen:bitset-choice, r=nnethercote

`BitSet` related perf improvements

This commit makes two changes:
 1. Changes `MaybeLiveLocals` to use `ChunkedBitSet`
 2. Overrides the `fold` method for the iterator for `ChunkedBitSet`

I have local benchmarks verifying that each of these changes individually yield significant perf improvements to #96451 . I'm hoping this will be true outside of that context too. If that is not the case, I'll try to gate things on where they help as needed

r? `@nnethercote` who I believe was working on closely related things, cc `@tmiasko` because of the destprop pr
This commit is contained in:
bors 2022-06-17 07:35:22 +00:00
commit ecdd374e61
5 changed files with 141 additions and 23 deletions

View file

@ -30,14 +30,14 @@ impl MaybeLiveLocals {
}
impl<'tcx> AnalysisDomain<'tcx> for MaybeLiveLocals {
type Domain = BitSet<Local>;
type Domain = ChunkedBitSet<Local>;
type Direction = Backward;
const NAME: &'static str = "liveness";
fn bottom_value(&self, body: &mir::Body<'tcx>) -> Self::Domain {
// bottom = not live
BitSet::new_empty(body.local_decls.len())
ChunkedBitSet::new_empty(body.local_decls.len())
}
fn initialize_start_block(&self, _: &mir::Body<'tcx>, _: &mut Self::Domain) {