match.pd: Optimize (((type)A * B) >> prec) != 0 into __imag__ .MUL_OVERFLOW [PR94914]
On x86 (the only target with umulv4_optab) one can use mull; seto to check
for overflow instead of performing wider multiplication and performing
comparison on the high bits.
2020-05-05 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/94914
* match.pd ((((type)A * B) >> prec) != 0 to .MUL_OVERFLOW(A, B) != 0):
New simplification.