[Bug tree-optimization/121772] [13/14/15/16 Regression] aarch64: ICE (invalid gimple) with vcombine since r13-1836-g8a1e05b7618fed

[acoplan at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121772

--- Comment #4 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Simplified testcase:

#include <arm_neon.h>
int16_t f(int16x4_t b) {
  return vaddvq_s16(vcombine_s16(b, vdup_n_s16 (0)));
}