http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55771
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #11 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-21
14:08:19 UTC ---
I'd keep it for FLOAT_TYPE_P -> FLOAT_TYPE_P for now, perhaps premature, but
clearly we don't have any GIMPLE optimization that would do the job (or RTL).
int
foo (double x)
{
float a = x;
double b = -x;
float c = -a;
float d = b;
return c == d;
}
int
bar (double x)
{
return (-(float) x) == ((float) -x);
}
with -O2 -ffast-math, bar is folded into return 1;, foo is quite a lot of code,
although both are equivalent. If the NEGATE_EXPR case is just removed, then
bar isn't optimized at all either.
