https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110591
--- Comment #2 from Hongtao.liu <crazylht at gmail dot com> --- (In reply to Hongtao.liu from comment #1) > I guess we can add a peephole for this, middle-end optimizer doesn't know > cmpccxadd set EFLAGS same as cmp. We already have a peephole for cmpxchg, for cmpxchg it's only valid for CCZmode, but for cmpccxadd, it should be ok for all CCmode since it sets EFLAGS exactly the same as CMP. The _CMPCCX_Z in the intrinsic is used as condition of updating memory.
