1/*
2 * Single-precision vector sin function.
3 *
4 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 * See https://llvm.org/LICENSE.txt for license information.
6 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 */
8
9#include "mathlib.h"
10#include "v_math.h"
11#if V_SUPPORTED
12
13static const float Poly[] = {
14 /* 1.886 ulp error */
15 0x1.5b2e76p-19f,
16 -0x1.9f42eap-13f,
17 0x1.110df4p-7f,
18 -0x1.555548p-3f,
19};
20#define Pi1 v_f32 (0x1.921fb6p+1f)
21#define Pi2 v_f32 (-0x1.777a5cp-24f)
22#define Pi3 v_f32 (-0x1.ee59dap-49f)
23#define A3 v_f32 (Poly[3])
24#define A5 v_f32 (Poly[2])
25#define A7 v_f32 (Poly[1])
26#define A9 v_f32 (Poly[0])
27#define RangeVal v_f32 (0x1p20f)
28#define InvPi v_f32 (0x1.45f306p-2f)
29#define Shift v_f32 (0x1.8p+23f)
30#define AbsMask v_u32 (0x7fffffff)
31
32VPCS_ATTR
33static v_f32_t
34specialcase (v_f32_t x, v_f32_t y, v_u32_t cmp)
35{
36 /* Fall back to scalar code. */
37 return v_call_f32 (f: sinf, x, y, p: cmp);
38}
39
40VPCS_ATTR
41v_f32_t
42V_NAME(sinf) (v_f32_t x)
43{
44 v_f32_t n, r, r2, y;
45 v_u32_t sign, odd, cmp;
46
47 r = v_as_f32_u32 (x: v_as_u32_f32 (x) & AbsMask);
48 sign = v_as_u32_f32 (x) & ~AbsMask;
49 cmp = v_cond_u32 (x: v_as_u32_f32 (x: r) >= v_as_u32_f32 (RangeVal));
50
51 /* n = rint(|x|/pi) */
52 n = v_fma_f32 (InvPi, y: r, Shift);
53 odd = v_as_u32_f32 (x: n) << 31;
54 n -= Shift;
55
56 /* r = |x| - n*pi (range reduction into -pi/2 .. pi/2) */
57 r = v_fma_f32 (x: -Pi1, y: n, z: r);
58 r = v_fma_f32 (x: -Pi2, y: n, z: r);
59 r = v_fma_f32 (x: -Pi3, y: n, z: r);
60
61 /* y = sin(r) */
62 r2 = r * r;
63 y = v_fma_f32 (A9, y: r2, A7);
64 y = v_fma_f32 (x: y, y: r2, A5);
65 y = v_fma_f32 (x: y, y: r2, A3);
66 y = v_fma_f32 (x: y * r2, y: r, z: r);
67
68 /* sign fix */
69 y = v_as_f32_u32 (x: v_as_u32_f32 (x: y) ^ sign ^ odd);
70
71 if (unlikely (v_any_u32 (cmp)))
72 return specialcase (x, y, cmp);
73 return y;
74}
75VPCS_ALIAS
76#endif
77

source code of libc/AOR_v20.02/math/v_sinf.c