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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#if __CLC_FPSIZE == 32
_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_cosh(__CLC_GENTYPE x) {
// After dealing with special cases the computation is split into regions as
// follows. abs(x) >= max_cosh_arg: cosh(x) = sign(x)*Inf abs(x) >=
// small_threshold: cosh(x) = sign(x)*exp(abs(x))/2 computed using the
// splitexp and scaleDouble functions as for exp_amd().
// abs(x) < small_threshold:
// compute p = exp(y) - 1 and then z = 0.5*(p+(p/(p+1.0)))
// cosh(x) is then z.
const __CLC_GENTYPE max_cosh_arg = 0x1.65a9fap+6f;
const __CLC_GENTYPE small_threshold = 0x1.0a2b24p+3f;
__CLC_UINTN ux = __CLC_AS_UINTN(x);
__CLC_GENTYPE y = __clc_fabs(x);
__CLC_UINTN aux = __CLC_AS_UINTN(y);
// Find the integer part y0 of y and the increment dy = y - y0. We then
// compute z = sinh(y) = sinh(y0)cosh(dy) + cosh(y0)sinh(dy) z = cosh(y) =
// cosh(y0)cosh(dy) + sinh(y0)sinh(dy) where sinh(y0) and cosh(y0) are
// tabulated above.
__CLC_INTN ind = __CLC_CONVERT_INTN(y);
ind = __CLC_CONVERT_UINTN(ind) > 36U ? 0 : ind;
__CLC_GENTYPE dy = y - __CLC_CONVERT_GENTYPE(ind);
__CLC_GENTYPE dy2 = dy * dy;
__CLC_GENTYPE sdy = __clc_mad(
dy2,
__clc_mad(
dy2,
__clc_mad(
dy2,
__clc_mad(
dy2,
__clc_mad(dy2,
__clc_mad(dy2, 0.7746188980094184251527126e-12f,
0.160576793121939886190847e-9f),
0.250521176994133472333666e-7f),
0.275573191913636406057211e-5f),
0.198412698413242405162014e-3f),
0.833333333333329931873097e-2f),
0.166666666666666667013899e0f);
sdy = __clc_mad(sdy, dy * dy2, dy);
__CLC_GENTYPE cdy = __clc_mad(
dy2,
__clc_mad(
dy2,
__clc_mad(
dy2,
__clc_mad(
dy2,
__clc_mad(dy2,
__clc_mad(dy2, 0.1163921388172173692062032e-10f,
0.208744349831471353536305e-8f),
0.275573350756016588011357e-6f),
0.248015872460622433115785e-4f),
0.138888888889814854814536e-2f),
0.416666666666660876512776e-1f),
0.500000000000000005911074e0f);
cdy = __clc_mad(cdy, dy2, 1.0f);
__CLC_GENTYPE sinhcoshh = __CLC_USE_TABLE(sinhcosh_tbl_head, ind);
__CLC_GENTYPE sinhcosht = __CLC_USE_TABLE(sinhcosh_tbl_tail, ind);
__CLC_GENTYPE z = __clc_mad(sinhcoshh, sdy, sinhcosht * cdy);
// When exp(-x) is insignificant compared to exp(x), return exp(x)/2
__CLC_GENTYPE t = __clc_exp(y - 0x1.62e500p-1f);
__CLC_GENTYPE zsmall = __clc_mad(0x1.a0210ep-18f, t, t);
z = y >= small_threshold ? zsmall : z;
// Corner cases
z = y >= max_cosh_arg ? __CLC_AS_GENTYPE((__CLC_UINTN)PINFBITPATT_SP32) : z;
z = aux > PINFBITPATT_SP32 ? __CLC_GENTYPE_NAN : z;
z = aux < 0x38800000 ? 1.0f : z;
return z;
}
#elif __CLC_FPSIZE == 64
_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_cosh(__CLC_GENTYPE x) {
// After dealing with special cases the computation is split into
// regions as follows:
//
// abs(x) >= max_cosh_arg:
// cosh(x) = sign(x)*Inf
//
// abs(x) >= small_threshold:
// cosh(x) = sign(x)*exp(abs(x))/2 computed using the
// splitexp and scaleDouble functions as for exp_amd().
//
// abs(x) < small_threshold:
// compute p = exp(y) - 1 and then z = 0.5*(p+(p/(p+1.0)))
// cosh(x) is then sign(x)*z.
// This is ln(2^1025) = 0x408633ce8fb9f87e
const __CLC_GENTYPE max_cosh_arg = 7.10475860073943977113e+02;
// This is where exp(-x) is insignificant compared to exp(x) = ln(2^27)
const __CLC_GENTYPE small_threshold = 0x1.2b708872320e2p+4;
__CLC_GENTYPE y = __clc_fabs(x);
// In this range we find the integer part y0 of y
// and the increment dy = y - y0. We then compute
// z = cosh(y) = cosh(y0)cosh(dy) + sinh(y0)sinh(dy)
// where sinh(y0) and cosh(y0) are tabulated above.
__CLC_INTN ind = __clc_min(__CLC_CONVERT_INTN(y), 36);
__CLC_GENTYPE dy = y - __CLC_CONVERT_GENTYPE(ind);
__CLC_GENTYPE dy2 = dy * dy;
__CLC_GENTYPE sdy =
dy * dy2 *
__clc_fma(
dy2,
__clc_fma(
dy2,
__clc_fma(
dy2,
__clc_fma(
dy2,
__clc_fma(dy2,
__clc_fma(dy2, 0.7746188980094184251527126e-12,
0.160576793121939886190847e-9),
0.250521176994133472333666e-7),
0.275573191913636406057211e-5),
0.198412698413242405162014e-3),
0.833333333333329931873097e-2),
0.166666666666666667013899e0);
__CLC_GENTYPE cdy =
dy2 *
__clc_fma(
dy2,
__clc_fma(
dy2,
__clc_fma(
dy2,
__clc_fma(
dy2,
__clc_fma(dy2,
__clc_fma(dy2, 0.1163921388172173692062032e-10,
0.208744349831471353536305e-8),
0.275573350756016588011357e-6),
0.248015872460622433115785e-4),
0.138888888889814854814536e-2),
0.416666666666660876512776e-1),
0.500000000000000005911074e0);
// At this point sinh(dy) is approximated by dy + sdy,
// and cosh(dy) is approximated by 1 + cdy.
__CLC_GENTYPE cl = __CLC_USE_TABLE(cosh_tbl_head, ind);
__CLC_GENTYPE ct = __CLC_USE_TABLE(cosh_tbl_tail, ind);
__CLC_GENTYPE sl = __CLC_USE_TABLE(sinh_tbl_head, ind);
__CLC_GENTYPE st = __CLC_USE_TABLE(sinh_tbl_tail, ind);
__CLC_GENTYPE z =
__clc_fma(
sl, dy,
__clc_fma(sl, sdy,
__clc_fma(cl, cdy,
__clc_fma(st, dy, __clc_fma(st, sdy, ct * cdy)) +
ct))) +
cl;
// Other cases
z = y < 0x1.0p-28 ? 1.0 : z;
__CLC_GENTYPE t = __clc_exp(y - 0x1.62e42fefa3800p-1);
t = __clc_fma(t, -0x1.ef35793c76641p-45, t);
z = y >= small_threshold ? t : z;
z = y >= max_cosh_arg ? __CLC_AS_GENTYPE((__CLC_ULONGN)PINFBITPATT_DP64) : z;
z = __clc_isinf(x) || __clc_isnan(x) ? y : z;
return z;
}
#elif __CLC_FPSIZE == 16
_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_cosh(__CLC_GENTYPE x) {
return __CLC_CONVERT_GENTYPE(__clc_cosh(__CLC_CONVERT_FLOATN(x)));
}
#endif