https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96921
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
On:
_Bool
foo (_Bool a, _Bool b)
{
int c = 1 - a;
int d = 1 - b;
int e = c & d;
return 1 - e;
}
_Bool
bar (_Bool a, _Bool b)
{
int c = 1 - a;
int d = 1 - b;
_Bool e = c & d;
return 1 - e;
}
_Bool
baz (_Bool a, _Bool b)
{
_Bool c = 1 - a;
_Bool d = 1 - b;
_Bool e = c & d;
return 1 - e;
}
we are able to optimize just baz. Rather than duplicating the bit_not vs.
bit_and/bit_ior etc. simplifications, I wonder if it wouldn't be better to
perform type demotion here, see that 1 - x is used in a boolean context and
that
x is ssa_name_has_boolean_range and turn that into bit_not on _Bool. Similarly
for the bit_and/ior/xor whose result is used in a boolean context and where
both operands are ssa_name_has_boolean_range. Thoughts on that?
