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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_CLC_DEF _CLC_OVERLOAD __CLC_GENTYPE __clc_exp_helper(__CLC_GENTYPE x,10 __CLC_GENTYPE x_min,11 __CLC_GENTYPE x_max,12 __CLC_GENTYPE r,13 __CLC_INTN n) {14 15 __CLC_INTN j = n & 0x3f;16 __CLC_INTN m = n >> 6;17 18 // 6 term tail of Taylor expansion of e^r19 __CLC_GENTYPE z2 =20 r * __clc_fma(21 r,22 __clc_fma(r,23 __clc_fma(r,24 __clc_fma(r,25 __clc_fma(r, 0x1.6c16c16c16c17p-10,26 0x1.1111111111111p-7),27 0x1.5555555555555p-5),28 0x1.5555555555555p-3),29 0x1.0000000000000p-1),30 1.0);31 32 __CLC_GENTYPE tv0 = __CLC_USE_TABLE(two_to_jby64_ep_tbl_head, j);33 __CLC_GENTYPE tv1 = __CLC_USE_TABLE(two_to_jby64_ep_tbl_tail, j);34 z2 = __clc_fma(tv0 + tv1, z2, tv1) + tv0;35 36 __CLC_INTN small_value =37 (m < -1022) || ((m == -1022) && __CLC_CONVERT_INTN(z2 < 1.0));38 39 __CLC_INTN n1 = m >> 2;40 __CLC_INTN n2 = m - n1;41 __CLC_GENTYPE z3 =42 z2 * __CLC_AS_GENTYPE((__CLC_CONVERT_LONGN(n1) + 1023) << 52);43 z3 *= __CLC_AS_GENTYPE((__CLC_CONVERT_LONGN(n2) + 1023) << 52);44 45 z2 = __clc_ldexp(z2, m);46 z2 = __CLC_CONVERT_LONGN(small_value) ? z3 : z2;47 48 z2 = __clc_isnan(x) ? x : z2;49 50 z2 = x > x_max ? __CLC_AS_GENTYPE((__CLC_ULONGN)PINFBITPATT_DP64) : z2;51 z2 = x < x_min ? 0.0 : z2;52 53 return z2;54}55