diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/e_exp.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/e_exp.c | 361 |
1 files changed, 0 insertions, 361 deletions
diff --git a/sysdeps/ieee754/dbl-64/e_exp.c b/sysdeps/ieee754/dbl-64/e_exp.c deleted file mode 100644 index 6757a14ce1..0000000000 --- a/sysdeps/ieee754/dbl-64/e_exp.c +++ /dev/null @@ -1,361 +0,0 @@ -/* - * IBM Accurate Mathematical Library - * written by International Business Machines Corp. - * Copyright (C) 2001-2017 Free Software Foundation, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU Lesser General Public License as published by - * the Free Software Foundation; either version 2.1 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public License - * along with this program; if not, see <http://www.gnu.org/licenses/>. - */ -/***************************************************************************/ -/* MODULE_NAME:uexp.c */ -/* */ -/* FUNCTION:uexp */ -/* exp1 */ -/* */ -/* FILES NEEDED:dla.h endian.h mpa.h mydefs.h uexp.h */ -/* mpa.c mpexp.x slowexp.c */ -/* */ -/* An ultimate exp routine. Given an IEEE double machine number x */ -/* it computes the correctly rounded (to nearest) value of e^x */ -/* Assumption: Machine arithmetic operations are performed in */ -/* round to nearest mode of IEEE 754 standard. */ -/* */ -/***************************************************************************/ - -#include <math.h> -#include "endian.h" -#include "uexp.h" -#include "mydefs.h" -#include "MathLib.h" -#include "uexp.tbl" -#include <math_private.h> -#include <fenv.h> -#include <float.h> - -#ifndef SECTION -# define SECTION -#endif - -double __slowexp (double); - -/* An ultimate exp routine. Given an IEEE double machine number x it computes - the correctly rounded (to nearest) value of e^x. */ -double -SECTION -__ieee754_exp (double x) -{ - double bexp, t, eps, del, base, y, al, bet, res, rem, cor; - mynumber junk1, junk2, binexp = {{0, 0}}; - int4 i, j, m, n, ex; - double retval; - - { - SET_RESTORE_ROUND (FE_TONEAREST); - - junk1.x = x; - m = junk1.i[HIGH_HALF]; - n = m & hugeint; - - if (n > smallint && n < bigint) - { - y = x * log2e.x + three51.x; - bexp = y - three51.x; /* multiply the result by 2**bexp */ - - junk1.x = y; - - eps = bexp * ln_two2.x; /* x = bexp*ln(2) + t - eps */ - t = x - bexp * ln_two1.x; - - y = t + three33.x; - base = y - three33.x; /* t rounded to a multiple of 2**-18 */ - junk2.x = y; - del = (t - base) - eps; /* x = bexp*ln(2) + base + del */ - eps = del + del * del * (p3.x * del + p2.x); - - binexp.i[HIGH_HALF] = (junk1.i[LOW_HALF] + 1023) << 20; - - i = ((junk2.i[LOW_HALF] >> 8) & 0xfffffffe) + 356; - j = (junk2.i[LOW_HALF] & 511) << 1; - - al = coar.x[i] * fine.x[j]; - bet = ((coar.x[i] * fine.x[j + 1] + coar.x[i + 1] * fine.x[j]) - + coar.x[i + 1] * fine.x[j + 1]); - - rem = (bet + bet * eps) + al * eps; - res = al + rem; - cor = (al - res) + rem; - if (res == (res + cor * err_0)) - { - retval = res * binexp.x; - goto ret; - } - else - { - retval = __slowexp (x); - goto ret; - } /*if error is over bound */ - } - - if (n <= smallint) - { - retval = 1.0; - goto ret; - } - - if (n >= badint) - { - if (n > infint) - { - retval = x + x; - goto ret; - } /* x is NaN */ - if (n < infint) - { - if (x > 0) - goto ret_huge; - else - goto ret_tiny; - } - /* x is finite, cause either overflow or underflow */ - if (junk1.i[LOW_HALF] != 0) - { - retval = x + x; - goto ret; - } /* x is NaN */ - retval = (x > 0) ? inf.x : zero; /* |x| = inf; return either inf or 0 */ - goto ret; - } - - y = x * log2e.x + three51.x; - bexp = y - three51.x; - junk1.x = y; - eps = bexp * ln_two2.x; - t = x - bexp * ln_two1.x; - y = t + three33.x; - base = y - three33.x; - junk2.x = y; - del = (t - base) - eps; - eps = del + del * del * (p3.x * del + p2.x); - i = ((junk2.i[LOW_HALF] >> 8) & 0xfffffffe) + 356; - j = (junk2.i[LOW_HALF] & 511) << 1; - al = coar.x[i] * fine.x[j]; - bet = ((coar.x[i] * fine.x[j + 1] + coar.x[i + 1] * fine.x[j]) - + coar.x[i + 1] * fine.x[j + 1]); - rem = (bet + bet * eps) + al * eps; - res = al + rem; - cor = (al - res) + rem; - if (m >> 31) - { - ex = junk1.i[LOW_HALF]; - if (res < 1.0) - { - res += res; - cor += cor; - ex -= 1; - } - if (ex >= -1022) - { - binexp.i[HIGH_HALF] = (1023 + ex) << 20; - if (res == (res + cor * err_0)) - { - retval = res * binexp.x; - goto ret; - } - else - { - retval = __slowexp (x); - goto check_uflow_ret; - } /*if error is over bound */ - } - ex = -(1022 + ex); - binexp.i[HIGH_HALF] = (1023 - ex) << 20; - res *= binexp.x; - cor *= binexp.x; - eps = 1.0000000001 + err_0 * binexp.x; - t = 1.0 + res; - y = ((1.0 - t) + res) + cor; - res = t + y; - cor = (t - res) + y; - if (res == (res + eps * cor)) - { - binexp.i[HIGH_HALF] = 0x00100000; - retval = (res - 1.0) * binexp.x; - goto check_uflow_ret; - } - else - { - retval = __slowexp (x); - goto check_uflow_ret; - } /* if error is over bound */ - check_uflow_ret: - if (retval < DBL_MIN) - { - double force_underflow = tiny * tiny; - math_force_eval (force_underflow); - } - if (retval == 0) - goto ret_tiny; - goto ret; - } - else - { - binexp.i[HIGH_HALF] = (junk1.i[LOW_HALF] + 767) << 20; - if (res == (res + cor * err_0)) - retval = res * binexp.x * t256.x; - else - retval = __slowexp (x); - if (isinf (retval)) - goto ret_huge; - else - goto ret; - } - } -ret: - return retval; - - ret_huge: - return hhuge * hhuge; - - ret_tiny: - return tiny * tiny; -} -#ifndef __ieee754_exp -strong_alias (__ieee754_exp, __exp_finite) -#endif - -/* Compute e^(x+xx). The routine also receives bound of error of previous - calculation. If after computing exp the error exceeds the allowed bounds, - the routine returns a non-positive number. Otherwise it returns the - computed result, which is always positive. */ -double -SECTION -__exp1 (double x, double xx, double error) -{ - double bexp, t, eps, del, base, y, al, bet, res, rem, cor; - mynumber junk1, junk2, binexp = {{0, 0}}; - int4 i, j, m, n, ex; - - junk1.x = x; - m = junk1.i[HIGH_HALF]; - n = m & hugeint; /* no sign */ - - if (n > smallint && n < bigint) - { - y = x * log2e.x + three51.x; - bexp = y - three51.x; /* multiply the result by 2**bexp */ - - junk1.x = y; - - eps = bexp * ln_two2.x; /* x = bexp*ln(2) + t - eps */ - t = x - bexp * ln_two1.x; - - y = t + three33.x; - base = y - three33.x; /* t rounded to a multiple of 2**-18 */ - junk2.x = y; - del = (t - base) + (xx - eps); /* x = bexp*ln(2) + base + del */ - eps = del + del * del * (p3.x * del + p2.x); - - binexp.i[HIGH_HALF] = (junk1.i[LOW_HALF] + 1023) << 20; - - i = ((junk2.i[LOW_HALF] >> 8) & 0xfffffffe) + 356; - j = (junk2.i[LOW_HALF] & 511) << 1; - - al = coar.x[i] * fine.x[j]; - bet = ((coar.x[i] * fine.x[j + 1] + coar.x[i + 1] * fine.x[j]) - + coar.x[i + 1] * fine.x[j + 1]); - - rem = (bet + bet * eps) + al * eps; - res = al + rem; - cor = (al - res) + rem; - if (res == (res + cor * (1.0 + error + err_1))) - return res * binexp.x; - else - return -10.0; - } - - if (n <= smallint) - return 1.0; /* if x->0 e^x=1 */ - - if (n >= badint) - { - if (n > infint) - return (zero / zero); /* x is NaN, return invalid */ - if (n < infint) - return ((x > 0) ? (hhuge * hhuge) : (tiny * tiny)); - /* x is finite, cause either overflow or underflow */ - if (junk1.i[LOW_HALF] != 0) - return (zero / zero); /* x is NaN */ - return ((x > 0) ? inf.x : zero); /* |x| = inf; return either inf or 0 */ - } - - y = x * log2e.x + three51.x; - bexp = y - three51.x; - junk1.x = y; - eps = bexp * ln_two2.x; - t = x - bexp * ln_two1.x; - y = t + three33.x; - base = y - three33.x; - junk2.x = y; - del = (t - base) + (xx - eps); - eps = del + del * del * (p3.x * del + p2.x); - i = ((junk2.i[LOW_HALF] >> 8) & 0xfffffffe) + 356; - j = (junk2.i[LOW_HALF] & 511) << 1; - al = coar.x[i] * fine.x[j]; - bet = ((coar.x[i] * fine.x[j + 1] + coar.x[i + 1] * fine.x[j]) - + coar.x[i + 1] * fine.x[j + 1]); - rem = (bet + bet * eps) + al * eps; - res = al + rem; - cor = (al - res) + rem; - if (m >> 31) - { - ex = junk1.i[LOW_HALF]; - if (res < 1.0) - { - res += res; - cor += cor; - ex -= 1; - } - if (ex >= -1022) - { - binexp.i[HIGH_HALF] = (1023 + ex) << 20; - if (res == (res + cor * (1.0 + error + err_1))) - return res * binexp.x; - else - return -10.0; - } - ex = -(1022 + ex); - binexp.i[HIGH_HALF] = (1023 - ex) << 20; - res *= binexp.x; - cor *= binexp.x; - eps = 1.00000000001 + (error + err_1) * binexp.x; - t = 1.0 + res; - y = ((1.0 - t) + res) + cor; - res = t + y; - cor = (t - res) + y; - if (res == (res + eps * cor)) - { - binexp.i[HIGH_HALF] = 0x00100000; - return (res - 1.0) * binexp.x; - } - else - return -10.0; - } - else - { - binexp.i[HIGH_HALF] = (junk1.i[LOW_HALF] + 767) << 20; - if (res == (res + cor * (1.0 + error + err_1))) - return res * binexp.x * t256.x; - else - return -10.0; - } -} |