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1//===----------------------------------------------------------------------===//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-exception6//7//===----------------------------------------------------------------------===//8 9#if __CLC_FPSIZE == 3210 11_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_cosh(__CLC_GENTYPE x) {12  // After dealing with special cases the computation is split into regions as13  // follows. abs(x) >= max_cosh_arg: cosh(x) = sign(x)*Inf abs(x) >=14  // small_threshold: cosh(x) = sign(x)*exp(abs(x))/2 computed using the15  // splitexp and scaleDouble functions as for exp_amd().16  // abs(x) < small_threshold:17  // compute p = exp(y) - 1 and then z = 0.5*(p+(p/(p+1.0)))18  // cosh(x) is then z.19 20  const __CLC_GENTYPE max_cosh_arg = 0x1.65a9fap+6f;21  const __CLC_GENTYPE small_threshold = 0x1.0a2b24p+3f;22 23  __CLC_UINTN ux = __CLC_AS_UINTN(x);24  __CLC_GENTYPE y = __clc_fabs(x);25  __CLC_UINTN aux = __CLC_AS_UINTN(y);26 27  // Find the integer part y0 of y and the increment dy = y - y0. We then28  // compute z = sinh(y) = sinh(y0)cosh(dy) + cosh(y0)sinh(dy) z = cosh(y) =29  // cosh(y0)cosh(dy) + sinh(y0)sinh(dy) where sinh(y0) and cosh(y0) are30  // tabulated above.31 32  __CLC_INTN ind = __CLC_CONVERT_INTN(y);33  ind = __CLC_CONVERT_UINTN(ind) > 36U ? 0 : ind;34 35  __CLC_GENTYPE dy = y - __CLC_CONVERT_GENTYPE(ind);36  __CLC_GENTYPE dy2 = dy * dy;37 38  __CLC_GENTYPE sdy = __clc_mad(39      dy2,40      __clc_mad(41          dy2,42          __clc_mad(43              dy2,44              __clc_mad(45                  dy2,46                  __clc_mad(dy2,47                            __clc_mad(dy2, 0.7746188980094184251527126e-12f,48                                      0.160576793121939886190847e-9f),49                            0.250521176994133472333666e-7f),50                  0.275573191913636406057211e-5f),51              0.198412698413242405162014e-3f),52          0.833333333333329931873097e-2f),53      0.166666666666666667013899e0f);54  sdy = __clc_mad(sdy, dy * dy2, dy);55 56  __CLC_GENTYPE cdy = __clc_mad(57      dy2,58      __clc_mad(59          dy2,60          __clc_mad(61              dy2,62              __clc_mad(63                  dy2,64                  __clc_mad(dy2,65                            __clc_mad(dy2, 0.1163921388172173692062032e-10f,66                                      0.208744349831471353536305e-8f),67                            0.275573350756016588011357e-6f),68                  0.248015872460622433115785e-4f),69              0.138888888889814854814536e-2f),70          0.416666666666660876512776e-1f),71      0.500000000000000005911074e0f);72  cdy = __clc_mad(cdy, dy2, 1.0f);73 74  __CLC_GENTYPE sinhcoshh = __CLC_USE_TABLE(sinhcosh_tbl_head, ind);75  __CLC_GENTYPE sinhcosht = __CLC_USE_TABLE(sinhcosh_tbl_tail, ind);76  __CLC_GENTYPE z = __clc_mad(sinhcoshh, sdy, sinhcosht * cdy);77 78  // When exp(-x) is insignificant compared to exp(x), return exp(x)/279  __CLC_GENTYPE t = __clc_exp(y - 0x1.62e500p-1f);80  __CLC_GENTYPE zsmall = __clc_mad(0x1.a0210ep-18f, t, t);81  z = y >= small_threshold ? zsmall : z;82 83  // Corner cases84  z = y >= max_cosh_arg ? __CLC_AS_GENTYPE((__CLC_UINTN)PINFBITPATT_SP32) : z;85  z = aux > PINFBITPATT_SP32 ? __CLC_GENTYPE_NAN : z;86  z = aux < 0x38800000 ? 1.0f : z;87 88  return z;89}90 91#elif __CLC_FPSIZE == 6492 93_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_cosh(__CLC_GENTYPE x) {94  // After dealing with special cases the computation is split into95  // regions as follows:96  //97  // abs(x) >= max_cosh_arg:98  // cosh(x) = sign(x)*Inf99  //100  // abs(x) >= small_threshold:101  // cosh(x) = sign(x)*exp(abs(x))/2 computed using the102  // splitexp and scaleDouble functions as for exp_amd().103  //104  // abs(x) < small_threshold:105  // compute p = exp(y) - 1 and then z = 0.5*(p+(p/(p+1.0)))106  // cosh(x) is then sign(x)*z.107 108  // This is ln(2^1025) = 0x408633ce8fb9f87e109  const __CLC_GENTYPE max_cosh_arg = 7.10475860073943977113e+02;110 111  // This is where exp(-x) is insignificant compared to exp(x) = ln(2^27)112  const __CLC_GENTYPE small_threshold = 0x1.2b708872320e2p+4;113 114  __CLC_GENTYPE y = __clc_fabs(x);115 116  // In this range we find the integer part y0 of y117  // and the increment dy = y - y0. We then compute118  // z = cosh(y) = cosh(y0)cosh(dy) + sinh(y0)sinh(dy)119  // where sinh(y0) and cosh(y0) are tabulated above.120 121  __CLC_INTN ind = __clc_min(__CLC_CONVERT_INTN(y), 36);122  __CLC_GENTYPE dy = y - __CLC_CONVERT_GENTYPE(ind);123  __CLC_GENTYPE dy2 = dy * dy;124 125  __CLC_GENTYPE sdy =126      dy * dy2 *127      __clc_fma(128          dy2,129          __clc_fma(130              dy2,131              __clc_fma(132                  dy2,133                  __clc_fma(134                      dy2,135                      __clc_fma(dy2,136                                __clc_fma(dy2, 0.7746188980094184251527126e-12,137                                          0.160576793121939886190847e-9),138                                0.250521176994133472333666e-7),139                      0.275573191913636406057211e-5),140                  0.198412698413242405162014e-3),141              0.833333333333329931873097e-2),142          0.166666666666666667013899e0);143 144  __CLC_GENTYPE cdy =145      dy2 *146      __clc_fma(147          dy2,148          __clc_fma(149              dy2,150              __clc_fma(151                  dy2,152                  __clc_fma(153                      dy2,154                      __clc_fma(dy2,155                                __clc_fma(dy2, 0.1163921388172173692062032e-10,156                                          0.208744349831471353536305e-8),157                                0.275573350756016588011357e-6),158                      0.248015872460622433115785e-4),159                  0.138888888889814854814536e-2),160              0.416666666666660876512776e-1),161          0.500000000000000005911074e0);162 163  // At this point sinh(dy) is approximated by dy + sdy,164  // and cosh(dy) is approximated by 1 + cdy.165  __CLC_GENTYPE cl = __CLC_USE_TABLE(cosh_tbl_head, ind);166  __CLC_GENTYPE ct = __CLC_USE_TABLE(cosh_tbl_tail, ind);167  __CLC_GENTYPE sl = __CLC_USE_TABLE(sinh_tbl_head, ind);168  __CLC_GENTYPE st = __CLC_USE_TABLE(sinh_tbl_tail, ind);169 170  __CLC_GENTYPE z =171      __clc_fma(172          sl, dy,173          __clc_fma(sl, sdy,174                    __clc_fma(cl, cdy,175                              __clc_fma(st, dy, __clc_fma(st, sdy, ct * cdy)) +176                                  ct))) +177      cl;178 179  // Other cases180  z = y < 0x1.0p-28 ? 1.0 : z;181 182  __CLC_GENTYPE t = __clc_exp(y - 0x1.62e42fefa3800p-1);183  t = __clc_fma(t, -0x1.ef35793c76641p-45, t);184  z = y >= small_threshold ? t : z;185 186  z = y >= max_cosh_arg ? __CLC_AS_GENTYPE((__CLC_ULONGN)PINFBITPATT_DP64) : z;187 188  z = __clc_isinf(x) || __clc_isnan(x) ? y : z;189 190  return z;191}192 193#elif __CLC_FPSIZE == 16194 195_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_cosh(__CLC_GENTYPE x) {196  return __CLC_CONVERT_GENTYPE(__clc_cosh(__CLC_CONVERT_FLOATN(x)));197}198 199#endif200