https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79151
--- Comment #2 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
Another test case.
It might even be profitable just to look for divisions, because these
are so expensive that packing/unpacking should always be
profitable.
double foo(double a, double b)
{
return 1/a + 1/b;
}
double v_foo (double a, double b)
{
typedef double v2do __attribute__((vector_size (16)));
v2do x, y;
x[0] = a;
x[1] = b;
y = 1/x;
return y[0] + y[1];
}
Assembly: foo is
movsd .LC0(%rip), %xmm2
movapd %xmm2, %xmm3
divsd %xmm1, %xmm2
divsd %xmm0, %xmm3
movapd %xmm3, %xmm0
addsd %xmm2, %xmm0
ret
and v_foo is
unpcklpd %xmm1, %xmm0
movapd .LC1(%rip), %xmm1
divpd %xmm0, %xmm1
movapd %xmm1, %xmm2
unpckhpd %xmm1, %xmm1
movapd %xmm1, %xmm0
addsd %xmm2, %xmm0
ret
