https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95464
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
I wonder where we'd simplify things like
(insn 67 66 68 3 (parallel [
(set (strict_low_part (subreg:QI (reg/v:SI 94 [ a ]) 0))
(ior:QI (subreg:QI (reg/v:SI 94 [ a ]) 0)
(const_int 5 [0x5])))
(clobber (reg:CC 17 flags))
]) "gallivm2.c":51:3 492 {*iorqi_1_slp}
(expr_list:REG_UNUSED (reg:CC 17 flags)
(nil)))
I guess simplify_rtx would just see the SET_SRC? The above might appear
quite frequently from bit fiddling RTL expansion I guess.
