1 /*
2 * Single-precision SVE asinh(x) function.
3 *
4 * Copyright (c) 2023, Arm Limited.
5 * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
6 */
7
8 #include "sv_math.h"
9 #include "include/mathlib.h"
10 #include "pl_sig.h"
11 #include "pl_test.h"
12
13 #include "sv_log1pf_inline.h"
14
15 #define BigBound (0x5f800000) /* asuint(0x1p64). */
16
17 static svfloat32_t NOINLINE
special_case(svfloat32_t x,svfloat32_t y,svbool_t special)18 special_case (svfloat32_t x, svfloat32_t y, svbool_t special)
19 {
20 return sv_call_f32 (asinhf, x, y, special);
21 }
22
23 /* Single-precision SVE asinh(x) routine. Implements the same algorithm as
24 vector asinhf and log1p.
25
26 Maximum error is 2.48 ULPs:
27 SV_NAME_F1 (asinh) (0x1.008864p-3) got 0x1.ffbbbcp-4
28 want 0x1.ffbbb8p-4. */
SV_NAME_F1(asinh)29 svfloat32_t SV_NAME_F1 (asinh) (svfloat32_t x, const svbool_t pg)
30 {
31 svfloat32_t ax = svabs_x (pg, x);
32 svuint32_t iax = svreinterpret_u32 (ax);
33 svuint32_t sign = sveor_x (pg, svreinterpret_u32 (x), iax);
34 svbool_t special = svcmpge (pg, iax, BigBound);
35
36 /* asinh(x) = log(x + sqrt(x * x + 1)).
37 For positive x, asinh(x) = log1p(x + x * x / (1 + sqrt(x * x + 1))). */
38 svfloat32_t ax2 = svmul_x (pg, ax, ax);
39 svfloat32_t d = svadd_x (pg, svsqrt_x (pg, svadd_x (pg, ax2, 1.0f)), 1.0f);
40 svfloat32_t y
41 = sv_log1pf_inline (svadd_x (pg, ax, svdiv_x (pg, ax2, d)), pg);
42
43 if (unlikely (svptest_any (pg, special)))
44 return special_case (
45 x, svreinterpret_f32 (svorr_x (pg, sign, svreinterpret_u32 (y))),
46 special);
47 return svreinterpret_f32 (svorr_x (pg, sign, svreinterpret_u32 (y)));
48 }
49
50 PL_SIG (SV, F, 1, asinh, -10.0, 10.0)
51 PL_TEST_ULP (SV_NAME_F1 (asinh), 1.98)
52 PL_TEST_SYM_INTERVAL (SV_NAME_F1 (asinh), 0, 0x1p-12, 4000)
53 PL_TEST_SYM_INTERVAL (SV_NAME_F1 (asinh), 0x1p-12, 1.0, 20000)
54 PL_TEST_SYM_INTERVAL (SV_NAME_F1 (asinh), 1.0, 0x1p64, 20000)
55 PL_TEST_SYM_INTERVAL (SV_NAME_F1 (asinh), 0x1p64, inf, 4000)
56