https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113744
Hongtao Liu <liuhongt at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |liuhongt at gcc dot gnu.org
--- Comment #2 from Hongtao Liu <liuhongt at gcc dot gnu.org> ---
7018; For comparisons against 1, -1 and 128, we may generate better code
7019; by converting cmp to add, inc or dec as done by peephole2. This pattern
7020; is matched then. We can't accept general immediate, because for
7021; case of overflows, the result is messed up.
7022; Also carry flag is reversed compared to cmp, so this conversion is valid
7023; only for comparisons not depending on it.
7024
It sounds to me those peephole2 can be extended to memory operand since APX_NDD
supports that. So it's not redudant m constraint in the pattern, but miss
optimization in those peepholes.
