https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110888
Thomas Koenig <tkoenig at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|fortran |middle-end
--- Comment #3 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
Interesting problem.
For
_19 = (*x_13(D))[0];
_20 = (*y_14(D))[0];
_21 = _19 * _20;
_22 = _21 + 0.0;
the multiplication cannot produce a signalling NaN, so the addition
of zero should always be a no-op. For this, a simpler test case would
be
double add(double a, double b)
{
return a*b + 0.0;
}
which gets me, on x86_64,
mulsd %xmm1, %xmm0
pxor %xmm1, %xmm1
addsd %xmm1, %xmm0
re
According to godbolt, icc produces
add:
mulsd %xmm1, %xmm0 #3.12
ret
which should be fine.
So, an issue for tree optimization?
