https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108786
Bug ID: 108786
Summary: bitmap_first_set_bit misses a bitmap_clear_first_bit
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: rguenth at gcc dot gnu.org
Target Milestone: ---
We have a repeated pattern for worklists doing
unsigned idx = bitmap_first_set_bit (b);
bitmap_clear_bit (b, idx);
but bitmap_clear_bit is more expensive and in particular prone to
clobber ->current which will pessimize other accesses to the same
bitmap.
bitmap_clear_first_bit would return the bit number cleared so it can
be used to pop an item from a worklist efficiently.
If the order doesn't matter a pick-one API also is missing which would
be more efficient for the tree form.
