https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70138
--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---
Simpler testcase not requiring strided stores:
double u[33];
__attribute__((noinline, noclone)) static void
foo (int *x)
{
double c = 0.0;
int a, b;
for (a = 0; a < 33; a++)
{
for (b = 0; b < 33; b++)
c = c + u[a];
u[a] *= 2.0;
}
*x = c;
}
int
main ()
{
int d, e;
for (d = 0; d < 33; d++)
{
u[d] = (d + 2);
__asm__ volatile ("" : : : "memory");
}
foo (&e);
if (e != 33 * (2 + 34) / 2 * 33)
__builtin_abort ();
return 0;
}
fails to vectorize on the gcc-5-branch because it can't create an epilogue
there.
