Performance results for fp-bench run under aarch64-linux-user on an Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz host:
- before: sqrt-single: 26.61 MFlops sqrt-double: 17.14 MFlops - after: sqrt-single: 95.06 MFlops sqrt-double: 89.05 MFlops Note that here we have a single implementation for both f32/f64. I tried the same trick we used before, but the results aren't as good: - w/ each using float32/64_is_normal or fpclassify etc.: sqrt-single: 95.50 MFlops sqrt-double: 84.55 MFlops - w/ both using fpclassify etc.: sqrt-single: 91.04 MFlops sqrt-double: 85.55 MFlops Signed-off-by: Emilio G. Cota <c...@braap.org> --- fpu/softfloat.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 2dedb13..ba7289b 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -2436,20 +2436,42 @@ float16 __attribute__((flatten)) float16_sqrt(float16 a, float_status *status) return float16_round_pack_canonical(pr, status); } -float32 __attribute__((flatten)) float32_sqrt(float32 a, float_status *status) +static float32 __attribute__((flatten, noinline)) +soft_float32_sqrt(float32 a, float_status *status) { FloatParts pa = float32_unpack_canonical(a, status); FloatParts pr = sqrt_float(pa, status, &float32_params); return float32_round_pack_canonical(pr, status); } -float64 __attribute__((flatten)) float64_sqrt(float64 a, float_status *status) +static float64 __attribute__((flatten, noinline)) +soft_float64_sqrt(float64 a, float_status *status) { FloatParts pa = float64_unpack_canonical(a, status); FloatParts pr = sqrt_float(pa, status, &float64_params); return float64_round_pack_canonical(pr, status); } +#define GEN_FPU_SQRT(name, soft_t, host_t, host_sqrt_func) \ + soft_t name(soft_t a, float_status *s) \ + { \ + soft_t ## _input_flush1(&a, s); \ + if (likely((soft_t ## _is_normal(a) || soft_t ## _is_zero(a)) && \ + !soft_t ## _is_neg(a) && \ + s->float_exception_flags & float_flag_inexact && \ + s->float_rounding_mode == float_round_nearest_even)) { \ + host_t ha = soft_t ## _to_ ## host_t(a); \ + host_t hr = host_sqrt_func(ha); \ + \ + return host_t ## _to_ ## soft_t(hr); \ + } \ + return soft_ ## soft_t ## _sqrt(a, s); \ + } + +GEN_FPU_SQRT(float32_sqrt, float32, float, sqrtf) +GEN_FPU_SQRT(float64_sqrt, float64, double, sqrt) +#undef GEN_FPU_SQRT + /*---------------------------------------------------------------------------- | Takes a 64-bit fixed-point value `absZ' with binary point between bits 6 -- 2.7.4