1//===-- Single-precision sinh function ------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "src/math/sinhf.h"
10#include "src/__support/FPUtil/FPBits.h"
11#include "src/__support/FPUtil/rounding_mode.h"
12#include "src/__support/macros/config.h"
13#include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
14#include "src/math/generic/explogxf.h"
15
16namespace LIBC_NAMESPACE_DECL {
17
18LLVM_LIBC_FUNCTION(float, sinhf, (float x)) {
19 using FPBits = typename fputil::FPBits<float>;
20 FPBits xbits(x);
21 uint32_t x_abs = xbits.abs().uintval();
22
23 // When |x| >= 90, or x is inf or nan
24 if (LIBC_UNLIKELY(x_abs >= 0x42b4'0000U || x_abs <= 0x3da0'0000U)) {
25 // |x| <= 0.078125
26 if (x_abs <= 0x3da0'0000U) {
27#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
28 // |x| = 0.0005589424981735646724700927734375
29 if (LIBC_UNLIKELY(x_abs == 0x3a12'85ffU)) {
30 if (fputil::fenv_is_round_to_nearest())
31 return x;
32 }
33#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
34
35 // |x| <= 2^-26
36 if (LIBC_UNLIKELY(x_abs <= 0x3280'0000U)) {
37 return static_cast<float>(
38 LIBC_UNLIKELY(x_abs == 0) ? x : (x + 0.25 * x * x * x));
39 }
40
41 double xdbl = x;
42 double x2 = xdbl * xdbl;
43 // Sollya: fpminimax(sinh(x),[|3,5,7|],[|D...|],[-1/16-1/64;1/16+1/64],x);
44 // Sollya output: x * (0x1p0 + x^0x1p1 * (0x1.5555555556583p-3 + x^0x1p1
45 // * (0x1.111110d239f1fp-7
46 // + x^0x1p1 * 0x1.a02b5a284013cp-13)))
47 // Therefore, output of Sollya = x * pe;
48 double pe = fputil::polyeval(x2, 0.0, 0x1.5555555556583p-3,
49 0x1.111110d239f1fp-7, 0x1.a02b5a284013cp-13);
50 return static_cast<float>(fputil::multiply_add(xdbl, pe, xdbl));
51 }
52
53 if (xbits.is_nan())
54 return x + 1.0f; // sNaN to qNaN + signal
55
56 if (xbits.is_inf())
57 return x;
58
59 int rounding = fputil::quick_get_round();
60 if (xbits.is_neg()) {
61 if (LIBC_UNLIKELY(rounding == FE_UPWARD || rounding == FE_TOWARDZERO))
62 return -FPBits::max_normal().get_val();
63 } else {
64 if (LIBC_UNLIKELY(rounding == FE_DOWNWARD || rounding == FE_TOWARDZERO))
65 return FPBits::max_normal().get_val();
66 }
67
68 fputil::set_errno_if_required(ERANGE);
69 fputil::raise_except_if_required(FE_OVERFLOW);
70
71 return x + FPBits::inf(xbits.sign()).get_val();
72 }
73
74 // sinh(x) = (e^x - e^(-x)) / 2.
75 return static_cast<float>(exp_pm_eval</*is_sinh*/ true>(x));
76}
77
78} // namespace LIBC_NAMESPACE_DECL
79

source code of libc/src/math/generic/sinhf.cpp