tree b849d2df917884f0bb140e9d0f5308ae0ca10d86
parent bf67aa3dd2d8b28d7618d8ec62cd9f6055366751
author Richard Henderson <richard.henderson@linaro.org> 1707523337 +0000
committer Richard Henderson <richard.henderson@linaro.org> 1714748615 -0700

util/bufferiszero: Add simd acceleration for aarch64

Because non-embedded aarch64 is expected to have AdvSIMD enabled, merely
double-check with the compiler flags for __ARM_NEON and don't bother with
a runtime check.  Otherwise, model the loop after the x86 SSE2 function.

Use UMAXV for the vector reduction.  This is 3 cycles on cortex-a76 and
2 cycles on neoverse-n1.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>