1*f3087befSAndrew Turner /*
2*f3087befSAndrew Turner * Single-precision vector cos function.
3*f3087befSAndrew Turner *
4*f3087befSAndrew Turner * Copyright (c) 2019-2024, Arm Limited.
5*f3087befSAndrew Turner * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
6*f3087befSAndrew Turner */
7*f3087befSAndrew Turner
8*f3087befSAndrew Turner #include "mathlib.h"
9*f3087befSAndrew Turner #include "v_math.h"
10*f3087befSAndrew Turner #include "test_defs.h"
11*f3087befSAndrew Turner #include "test_sig.h"
12*f3087befSAndrew Turner
13*f3087befSAndrew Turner static const struct data
14*f3087befSAndrew Turner {
15*f3087befSAndrew Turner float32x4_t poly[4];
16*f3087befSAndrew Turner float32x4_t range_val, inv_pi, pi_1, pi_2, pi_3;
17*f3087befSAndrew Turner } data = {
18*f3087befSAndrew Turner /* 1.886 ulp error. */
19*f3087befSAndrew Turner .poly = { V4 (-0x1.555548p-3f), V4 (0x1.110df4p-7f), V4 (-0x1.9f42eap-13f),
20*f3087befSAndrew Turner V4 (0x1.5b2e76p-19f) },
21*f3087befSAndrew Turner
22*f3087befSAndrew Turner .pi_1 = V4 (0x1.921fb6p+1f),
23*f3087befSAndrew Turner .pi_2 = V4 (-0x1.777a5cp-24f),
24*f3087befSAndrew Turner .pi_3 = V4 (-0x1.ee59dap-49f),
25*f3087befSAndrew Turner
26*f3087befSAndrew Turner .inv_pi = V4 (0x1.45f306p-2f),
27*f3087befSAndrew Turner .range_val = V4 (0x1p20f)
28*f3087befSAndrew Turner };
29*f3087befSAndrew Turner
30*f3087befSAndrew Turner #define C(i) d->poly[i]
31*f3087befSAndrew Turner
32*f3087befSAndrew Turner static float32x4_t VPCS_ATTR NOINLINE
special_case(float32x4_t x,float32x4_t y,uint32x4_t odd,uint32x4_t cmp)33*f3087befSAndrew Turner special_case (float32x4_t x, float32x4_t y, uint32x4_t odd, uint32x4_t cmp)
34*f3087befSAndrew Turner {
35*f3087befSAndrew Turner /* Fall back to scalar code. */
36*f3087befSAndrew Turner y = vreinterpretq_f32_u32 (veorq_u32 (vreinterpretq_u32_f32 (y), odd));
37*f3087befSAndrew Turner return v_call_f32 (cosf, x, y, cmp);
38*f3087befSAndrew Turner }
39*f3087befSAndrew Turner
V_NAME_F1(cos)40*f3087befSAndrew Turner float32x4_t VPCS_ATTR NOINLINE V_NAME_F1 (cos) (float32x4_t x)
41*f3087befSAndrew Turner {
42*f3087befSAndrew Turner const struct data *d = ptr_barrier (&data);
43*f3087befSAndrew Turner float32x4_t n, r, r2, r3, y;
44*f3087befSAndrew Turner uint32x4_t odd, cmp;
45*f3087befSAndrew Turner
46*f3087befSAndrew Turner #if WANT_SIMD_EXCEPT
47*f3087befSAndrew Turner r = vabsq_f32 (x);
48*f3087befSAndrew Turner cmp = vcgeq_u32 (vreinterpretq_u32_f32 (r),
49*f3087befSAndrew Turner vreinterpretq_u32_f32 (d->range_val));
50*f3087befSAndrew Turner if (unlikely (v_any_u32 (cmp)))
51*f3087befSAndrew Turner /* If fenv exceptions are to be triggered correctly, set any special lanes
52*f3087befSAndrew Turner to 1 (which is neutral w.r.t. fenv). These lanes will be fixed by
53*f3087befSAndrew Turner special-case handler later. */
54*f3087befSAndrew Turner r = vbslq_f32 (cmp, v_f32 (1.0f), r);
55*f3087befSAndrew Turner #else
56*f3087befSAndrew Turner cmp = vcageq_f32 (x, d->range_val);
57*f3087befSAndrew Turner r = x;
58*f3087befSAndrew Turner #endif
59*f3087befSAndrew Turner
60*f3087befSAndrew Turner /* n = rint((|x|+pi/2)/pi) - 0.5. */
61*f3087befSAndrew Turner n = vrndaq_f32 (vfmaq_f32 (v_f32 (0.5), r, d->inv_pi));
62*f3087befSAndrew Turner odd = vshlq_n_u32 (vreinterpretq_u32_s32 (vcvtq_s32_f32 (n)), 31);
63*f3087befSAndrew Turner n = vsubq_f32 (n, v_f32 (0.5f));
64*f3087befSAndrew Turner
65*f3087befSAndrew Turner /* r = |x| - n*pi (range reduction into -pi/2 .. pi/2). */
66*f3087befSAndrew Turner r = vfmsq_f32 (r, d->pi_1, n);
67*f3087befSAndrew Turner r = vfmsq_f32 (r, d->pi_2, n);
68*f3087befSAndrew Turner r = vfmsq_f32 (r, d->pi_3, n);
69*f3087befSAndrew Turner
70*f3087befSAndrew Turner /* y = sin(r). */
71*f3087befSAndrew Turner r2 = vmulq_f32 (r, r);
72*f3087befSAndrew Turner r3 = vmulq_f32 (r2, r);
73*f3087befSAndrew Turner y = vfmaq_f32 (C (2), C (3), r2);
74*f3087befSAndrew Turner y = vfmaq_f32 (C (1), y, r2);
75*f3087befSAndrew Turner y = vfmaq_f32 (C (0), y, r2);
76*f3087befSAndrew Turner y = vfmaq_f32 (r, y, r3);
77*f3087befSAndrew Turner
78*f3087befSAndrew Turner if (unlikely (v_any_u32 (cmp)))
79*f3087befSAndrew Turner return special_case (x, y, odd, cmp);
80*f3087befSAndrew Turner return vreinterpretq_f32_u32 (veorq_u32 (vreinterpretq_u32_f32 (y), odd));
81*f3087befSAndrew Turner }
82*f3087befSAndrew Turner
83*f3087befSAndrew Turner HALF_WIDTH_ALIAS_F1 (cos)
84*f3087befSAndrew Turner
85*f3087befSAndrew Turner TEST_SIG (V, F, 1, cos, -3.1, 3.1)
86*f3087befSAndrew Turner TEST_ULP (V_NAME_F1 (cos), 1.4)
87*f3087befSAndrew Turner TEST_DISABLE_FENV_IF_NOT (V_NAME_F1 (cos), WANT_SIMD_EXCEPT)
88*f3087befSAndrew Turner TEST_SYM_INTERVAL (V_NAME_F1 (cos), 0, 0x1p20, 500000)
89*f3087befSAndrew Turner TEST_SYM_INTERVAL (V_NAME_F1 (cos), 0x1p20, inf, 10000)
90