1*f3087befSAndrew Turner /*
2*f3087befSAndrew Turner * Single-precision SVE sinpi(x) function.
3*f3087befSAndrew Turner *
4*f3087befSAndrew Turner * Copyright (c) 2023-2024, 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 "sv_math.h"
9*f3087befSAndrew Turner #include "mathlib.h"
10*f3087befSAndrew Turner #include "test_sig.h"
11*f3087befSAndrew Turner #include "test_defs.h"
12*f3087befSAndrew Turner #include "sv_poly_f32.h"
13*f3087befSAndrew Turner
14*f3087befSAndrew Turner static const struct data
15*f3087befSAndrew Turner {
16*f3087befSAndrew Turner float poly[6], range_val;
17*f3087befSAndrew Turner } data = {
18*f3087befSAndrew Turner /* Taylor series coefficents for sin(pi * x). */
19*f3087befSAndrew Turner .poly = { 0x1.921fb6p1f, -0x1.4abbcep2f, 0x1.466bc6p1f, -0x1.32d2ccp-1f,
20*f3087befSAndrew Turner 0x1.50783p-4f, -0x1.e30750p-8f },
21*f3087befSAndrew Turner .range_val = 0x1p31,
22*f3087befSAndrew Turner };
23*f3087befSAndrew Turner
24*f3087befSAndrew Turner /* A fast SVE implementation of sinpif.
25*f3087befSAndrew Turner Maximum error 2.48 ULP:
26*f3087befSAndrew Turner _ZGVsMxv_sinpif(0x1.d062b6p-2) got 0x1.fa8c06p-1
27*f3087befSAndrew Turner want 0x1.fa8c02p-1. */
SV_NAME_F1(sinpi)28*f3087befSAndrew Turner svfloat32_t SV_NAME_F1 (sinpi) (svfloat32_t x, const svbool_t pg)
29*f3087befSAndrew Turner {
30*f3087befSAndrew Turner const struct data *d = ptr_barrier (&data);
31*f3087befSAndrew Turner
32*f3087befSAndrew Turner /* range reduction into -1/2 .. 1/2
33*f3087befSAndrew Turner with n = rint(x) and r = r - n. */
34*f3087befSAndrew Turner svfloat32_t n = svrinta_x (pg, x);
35*f3087befSAndrew Turner svfloat32_t r = svsub_x (pg, x, n);
36*f3087befSAndrew Turner
37*f3087befSAndrew Turner /* Result should be negated based on if n is odd or not. */
38*f3087befSAndrew Turner svbool_t cmp = svaclt (pg, x, d->range_val);
39*f3087befSAndrew Turner svuint32_t intn = svreinterpret_u32 (svcvt_s32_z (pg, n));
40*f3087befSAndrew Turner svuint32_t sign = svlsl_z (cmp, intn, 31);
41*f3087befSAndrew Turner
42*f3087befSAndrew Turner /* y = sin(r). */
43*f3087befSAndrew Turner svfloat32_t r2 = svmul_x (pg, r, r);
44*f3087befSAndrew Turner svfloat32_t y = sv_horner_5_f32_x (pg, r2, d->poly);
45*f3087befSAndrew Turner y = svmul_x (pg, y, r);
46*f3087befSAndrew Turner
47*f3087befSAndrew Turner return svreinterpret_f32 (sveor_x (pg, svreinterpret_u32 (y), sign));
48*f3087befSAndrew Turner }
49*f3087befSAndrew Turner
50*f3087befSAndrew Turner #if WANT_TRIGPI_TESTS
51*f3087befSAndrew Turner TEST_ULP (SV_NAME_F1 (sinpi), 1.99)
52*f3087befSAndrew Turner TEST_DISABLE_FENV (SV_NAME_F1 (sinpi))
53*f3087befSAndrew Turner TEST_SYM_INTERVAL (SV_NAME_F1 (sinpi), 0, 0x1p-31, 5000)
54*f3087befSAndrew Turner TEST_SYM_INTERVAL (SV_NAME_F1 (sinpi), 0x1p-31, 0.5, 10000)
55*f3087befSAndrew Turner TEST_SYM_INTERVAL (SV_NAME_F1 (sinpi), 0.5, 0x1p22f, 10000)
56*f3087befSAndrew Turner TEST_SYM_INTERVAL (SV_NAME_F1 (sinpi), 0x1p22f, inf, 10000)
57*f3087befSAndrew Turner #endif
58*f3087befSAndrew Turner CLOSE_SVE_ATTR
59