On 15/2/24 09:14, Richard Henderson wrote:
Because the three alternatives are monotonic, we don't
need to keep a couple of bitmasks, just identify the
strongest alternative at startup.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
util/bufferiszero.c | 56 ++++++++++++++++++---------------------------
1 file changed, 22 insertions(+), 34 deletions(-)
enum {
ACCEL_DEFAULT,
ACCEL_SSE2,
ACCEL_AVX2,
};
+static biz_accel_fn const accel_table[] = {
[ACCEL_DEFAULT] =
+ buffer_is_zero_int_ge256,
[ACCEL_SSE2] =
+ buffer_zero_sse2,
#ifdef CONFIG_AVX2_OPT
[ACCEL_AVX2] =
+ buffer_zero_avx2,
#endif
+static unsigned accel_index;
static void __attribute__((constructor)) init_accel(void)
{
- used_accel = select_accel_cpuinfo(cpuinfo_init());
+ unsigned info = cpuinfo_init();
+ unsigned index = (info & CPUINFO_SSE2 ? 1 : 0);
... ? ACCEL_SSE2 : ACCEL_DEFAULT;
+
+#ifdef CONFIG_AVX2_OPT
+ if (info & CPUINFO_AVX2) {
+ index = 2;
... = ACCEL_AVX2
+ }
+#endif
+
+ accel_index = index;
+ buffer_is_zero_accel = accel_table[index];
}
Preferably introducing accel enum:
Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>
