Files
clang-p2996/libclc/generic/lib/math/cosh.cl
Romaric Jodin 7e6a73959a libclc: increase fp16 support (#98149)
Increase fp16 support to allow clspv to continue to be OpenCL compliant
following the update of the OpenCL-CTS adding more testing on math
functions and conversions with half.

Math functions are implemented by upscaling to fp32 and using the fp32
implementation. It garantees the accuracy required for half-precision
float-point by the CTS.
2024-07-18 12:00:41 +01:00

195 lines
6.6 KiB
Common Lisp

/*
* Copyright (c) 2014,2015 Advanced Micro Devices, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <clc/clc.h>
#include "math.h"
#include "tables.h"
#include "../clcmacro.h"
_CLC_OVERLOAD _CLC_DEF float cosh(float 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 float max_cosh_arg = 0x1.65a9fap+6f;
const float small_threshold = 0x1.0a2b24p+3f;
uint ux = as_uint(x);
uint aux = ux & EXSIGNBIT_SP32;
float y = as_float(aux);
// 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.
int ind = (int)y;
ind = (uint)ind > 36U ? 0 : ind;
float dy = y - ind;
float dy2 = dy * dy;
float sdy = mad(dy2,
mad(dy2,
mad(dy2,
mad(dy2,
mad(dy2,
mad(dy2, 0.7746188980094184251527126e-12f, 0.160576793121939886190847e-9f),
0.250521176994133472333666e-7f),
0.275573191913636406057211e-5f),
0.198412698413242405162014e-3f),
0.833333333333329931873097e-2f),
0.166666666666666667013899e0f);
sdy = mad(sdy, dy*dy2, dy);
float cdy = mad(dy2,
mad(dy2,
mad(dy2,
mad(dy2,
mad(dy2,
mad(dy2, 0.1163921388172173692062032e-10f, 0.208744349831471353536305e-8f),
0.275573350756016588011357e-6f),
0.248015872460622433115785e-4f),
0.138888888889814854814536e-2f),
0.416666666666660876512776e-1f),
0.500000000000000005911074e0f);
cdy = mad(cdy, dy2, 1.0f);
float2 tv = USE_TABLE(sinhcosh_tbl, ind);
float z = mad(tv.s0, sdy, tv.s1 * cdy);
// When exp(-x) is insignificant compared to exp(x), return exp(x)/2
float t = exp(y - 0x1.62e500p-1f);
float zsmall = mad(0x1.a0210ep-18f, t, t);
z = y >= small_threshold ? zsmall : z;
// Corner cases
z = y >= max_cosh_arg ? as_float(PINFBITPATT_SP32) : z;
z = aux > PINFBITPATT_SP32 ? as_float(QNANBITPATT_SP32) : z;
z = aux < 0x38800000 ? 1.0f : z;
return z;
}
_CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, float, cosh, float);
#ifdef cl_khr_fp64
#pragma OPENCL EXTENSION cl_khr_fp64 : enable
_CLC_OVERLOAD _CLC_DEF double cosh(double 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)
const double max_cosh_arg = 7.10475860073943977113e+02; // 0x408633ce8fb9f87e
// This is where exp(-x) is insignificant compared to exp(x) = ln(2^27)
const double small_threshold = 0x1.2b708872320e2p+4;
double y = 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.
int ind = min((int)y, 36);
double dy = y - ind;
double dy2 = dy * dy;
double sdy = dy * dy2 *
fma(dy2,
fma(dy2,
fma(dy2,
fma(dy2,
fma(dy2,
fma(dy2, 0.7746188980094184251527126e-12, 0.160576793121939886190847e-9),
0.250521176994133472333666e-7),
0.275573191913636406057211e-5),
0.198412698413242405162014e-3),
0.833333333333329931873097e-2),
0.166666666666666667013899e0);
double cdy = dy2 * fma(dy2,
fma(dy2,
fma(dy2,
fma(dy2,
fma(dy2,
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.
double2 tv = USE_TABLE(cosh_tbl, ind);
double cl = tv.s0;
double ct = tv.s1;
tv = USE_TABLE(sinh_tbl, ind);
double sl = tv.s0;
double st = tv.s1;
double z = fma(sl, dy, fma(sl, sdy, fma(cl, cdy, fma(st, dy, fma(st, sdy, ct*cdy)) + ct))) + cl;
// Other cases
z = y < 0x1.0p-28 ? 1.0 : z;
double t = exp(y - 0x1.62e42fefa3800p-1);
t = fma(t, -0x1.ef35793c76641p-45, t);
z = y >= small_threshold ? t : z;
z = y >= max_cosh_arg ? as_double(PINFBITPATT_DP64) : z;
z = isinf(x) | isnan(x) ? y : z;
return z;
}
_CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, cosh, double)
#endif
_CLC_DEFINE_UNARY_BUILTIN_FP16(cosh)