https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65265
--- Comment #1 from Oleg Endo <olegendo at gcc dot gnu.org> ---
Actually, this can be also used for xor or and-not etc combinations. E.g. an
and-not sequence:
mov #-1,r12
tst r0,r0 T1
negc r12,r12 !T1
tst r1,r1 T0
movt r10
and r12,r10 r1 = T0 & !T1
tst r10,r10 T = !(T0 & !T1)
bt .L4315
could be done better as:
tst r0,r0 T1
movt r0
tst r1,r1 T0
rotcl r0 t0 = T1 T0
cmp/eq #1,r0 T = T0 & !T1
bf .L4315
Since the comparison combination is more complex (in terms of SH insns), it's
also beneficial to do it for 2 comparisons.
