xref: /freebsd/contrib/arm-optimized-routines/math/aarch64/sve/acoshf.c (revision f3087bef11543b42e0d69b708f367097a4118d24)
1 /*
2  * Single-precision SVE acosh(x) function.
3  * Copyright (c) 2023-2024, Arm Limited.
4  * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
5  */
6 
7 #include "sv_math.h"
8 #include "test_sig.h"
9 #include "test_defs.h"
10 
11 #define One 0x3f800000
12 #define Thres 0x20000000 /* asuint(0x1p64) - One.  */
13 
14 #include "sv_log1pf_inline.h"
15 
16 static svfloat32_t NOINLINE
special_case(svfloat32_t xm1,svfloat32_t tmp,svbool_t special)17 special_case (svfloat32_t xm1, svfloat32_t tmp, svbool_t special)
18 {
19   svfloat32_t x = svadd_x (svptrue_b32 (), xm1, 1.0f);
20   svfloat32_t y = sv_log1pf_inline (tmp, svptrue_b32 ());
21   return sv_call_f32 (acoshf, x, y, special);
22 }
23 
24 /* Single-precision SVE acosh(x) routine. Implements the same algorithm as
25    vector acoshf and log1p.
26 
27    Maximum error is 2.47 ULPs:
28    SV_NAME_F1 (acosh) (0x1.01ca76p+0) got 0x1.e435a6p-4
29 				     want 0x1.e435a2p-4.  */
SV_NAME_F1(acosh)30 svfloat32_t SV_NAME_F1 (acosh) (svfloat32_t x, const svbool_t pg)
31 {
32   svuint32_t ix = svreinterpret_u32 (x);
33   svbool_t special = svcmpge (pg, svsub_x (pg, ix, One), Thres);
34 
35   svfloat32_t xm1 = svsub_x (pg, x, 1.0f);
36   svfloat32_t u = svmul_x (pg, xm1, svadd_x (pg, x, 1.0f));
37   svfloat32_t tmp = svadd_x (pg, xm1, svsqrt_x (pg, u));
38 
39   if (unlikely (svptest_any (pg, special)))
40     return special_case (xm1, tmp, special);
41   return sv_log1pf_inline (tmp, pg);
42 }
43 
44 TEST_SIG (SV, F, 1, acosh, 1.0, 10.0)
45 TEST_ULP (SV_NAME_F1 (acosh), 1.97)
46 TEST_DISABLE_FENV (SV_NAME_F1 (acosh))
47 TEST_INTERVAL (SV_NAME_F1 (acosh), 0, 1, 500)
48 TEST_INTERVAL (SV_NAME_F1 (acosh), 1, 0x1p64, 100000)
49 TEST_INTERVAL (SV_NAME_F1 (acosh), 0x1p64, inf, 1000)
50 TEST_INTERVAL (SV_NAME_F1 (acosh), -0, -inf, 1000)
51 CLOSE_SVE_ATTR
52