diff options
Diffstat (limited to 'math/aarch64/v_sinf.c')
-rw-r--r-- | math/aarch64/v_sinf.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/math/aarch64/v_sinf.c b/math/aarch64/v_sinf.c new file mode 100644 index 000000000000..336879844459 --- /dev/null +++ b/math/aarch64/v_sinf.c @@ -0,0 +1,82 @@ +/* + * Single-precision vector sin function. + * + * Copyright (c) 2019-2023, Arm Limited. + * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception + */ + +#include "mathlib.h" +#include "v_math.h" + +static const struct data +{ + float32x4_t poly[4]; + float32x4_t range_val, inv_pi, shift, pi_1, pi_2, pi_3; +} data = { + /* 1.886 ulp error. */ + .poly = { V4 (-0x1.555548p-3f), V4 (0x1.110df4p-7f), V4 (-0x1.9f42eap-13f), + V4 (0x1.5b2e76p-19f) }, + + .pi_1 = V4 (0x1.921fb6p+1f), + .pi_2 = V4 (-0x1.777a5cp-24f), + .pi_3 = V4 (-0x1.ee59dap-49f), + + .inv_pi = V4 (0x1.45f306p-2f), + .shift = V4 (0x1.8p+23f), + .range_val = V4 (0x1p20f) +}; + +#if WANT_SIMD_EXCEPT +# define TinyBound v_u32 (0x21000000) /* asuint32(0x1p-61f). */ +# define Thresh v_u32 (0x28800000) /* RangeVal - TinyBound. */ +#endif + +#define C(i) d->poly[i] + +static float32x4_t VPCS_ATTR NOINLINE +special_case (float32x4_t x, float32x4_t y, uint32x4_t odd, uint32x4_t cmp) +{ + /* Fall back to scalar code. */ + y = vreinterpretq_f32_u32 (veorq_u32 (vreinterpretq_u32_f32 (y), odd)); + return v_call_f32 (sinf, x, y, cmp); +} + +float32x4_t VPCS_ATTR V_NAME_F1 (sin) (float32x4_t x) +{ + const struct data *d = ptr_barrier (&data); + float32x4_t n, r, r2, y; + uint32x4_t odd, cmp; + +#if WANT_SIMD_EXCEPT + uint32x4_t ir = vreinterpretq_u32_f32 (vabsq_f32 (x)); + cmp = vcgeq_u32 (vsubq_u32 (ir, TinyBound), Thresh); + /* If fenv exceptions are to be triggered correctly, set any special lanes + to 1 (which is neutral w.r.t. fenv). These lanes will be fixed by + special-case handler later. */ + r = vbslq_f32 (cmp, vreinterpretq_f32_u32 (cmp), x); +#else + r = x; + cmp = vcageq_f32 (x, d->range_val); +#endif + + /* n = rint(|x|/pi) */ + n = vfmaq_f32 (d->shift, d->inv_pi, r); + odd = vshlq_n_u32 (vreinterpretq_u32_f32 (n), 31); + n = vsubq_f32 (n, d->shift); + + /* r = |x| - n*pi (range reduction into -pi/2 .. pi/2) */ + r = vfmsq_f32 (r, d->pi_1, n); + r = vfmsq_f32 (r, d->pi_2, n); + r = vfmsq_f32 (r, d->pi_3, n); + + /* y = sin(r) */ + r2 = vmulq_f32 (r, r); + y = vfmaq_f32 (C (2), C (3), r2); + y = vfmaq_f32 (C (1), y, r2); + y = vfmaq_f32 (C (0), y, r2); + y = vfmaq_f32 (r, vmulq_f32 (y, r2), r); + + if (unlikely (v_any_u32 (cmp))) + return special_case (x, y, odd, cmp); + return vreinterpretq_f32_u32 (veorq_u32 (vreinterpretq_u32_f32 (y), odd)); +} |