1f9f848faSopenharmony_ci/*- 2f9f848faSopenharmony_ci * SPDX-License-Identifier: BSD-2-Clause 3f9f848faSopenharmony_ci * 4f9f848faSopenharmony_ci * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG> 5f9f848faSopenharmony_ci * All rights reserved. 6f9f848faSopenharmony_ci * 7f9f848faSopenharmony_ci * Redistribution and use in source and binary forms, with or without 8f9f848faSopenharmony_ci * modification, are permitted provided that the following conditions 9f9f848faSopenharmony_ci * are met: 10f9f848faSopenharmony_ci * 1. Redistributions of source code must retain the above copyright 11f9f848faSopenharmony_ci * notice, this list of conditions and the following disclaimer. 12f9f848faSopenharmony_ci * 2. Redistributions in binary form must reproduce the above copyright 13f9f848faSopenharmony_ci * notice, this list of conditions and the following disclaimer in the 14f9f848faSopenharmony_ci * documentation and/or other materials provided with the distribution. 15f9f848faSopenharmony_ci * 16f9f848faSopenharmony_ci * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17f9f848faSopenharmony_ci * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18f9f848faSopenharmony_ci * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19f9f848faSopenharmony_ci * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20f9f848faSopenharmony_ci * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21f9f848faSopenharmony_ci * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22f9f848faSopenharmony_ci * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23f9f848faSopenharmony_ci * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24f9f848faSopenharmony_ci * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25f9f848faSopenharmony_ci * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26f9f848faSopenharmony_ci * SUCH DAMAGE. 27f9f848faSopenharmony_ci */ 28f9f848faSopenharmony_ci 29f9f848faSopenharmony_ci#include <float.h> 30f9f848faSopenharmony_ci#include <math.h> 31f9f848faSopenharmony_ci 32f9f848faSopenharmony_ci#include "fpmath.h" 33f9f848faSopenharmony_ci 34f9f848faSopenharmony_ci#if LDBL_MAX_EXP != 0x4000 35f9f848faSopenharmony_ci#error "Unsupported long double format" 36f9f848faSopenharmony_ci#endif 37f9f848faSopenharmony_ci 38f9f848faSopenharmony_cilong double 39f9f848faSopenharmony_cifrexpl(long double x, int *ex) 40f9f848faSopenharmony_ci{ 41f9f848faSopenharmony_ci union IEEEl2bits u; 42f9f848faSopenharmony_ci 43f9f848faSopenharmony_ci u.e = x; 44f9f848faSopenharmony_ci switch (u.bits.exp) { 45f9f848faSopenharmony_ci case 0: /* 0 or subnormal */ 46f9f848faSopenharmony_ci if ((u.bits.manl | u.bits.manh) == 0) { 47f9f848faSopenharmony_ci *ex = 0; 48f9f848faSopenharmony_ci } else { 49f9f848faSopenharmony_ci u.e *= 0x1.0p514; 50f9f848faSopenharmony_ci *ex = u.bits.exp - 0x4200; 51f9f848faSopenharmony_ci u.bits.exp = 0x3ffe; 52f9f848faSopenharmony_ci } 53f9f848faSopenharmony_ci break; 54f9f848faSopenharmony_ci case 0x7fff: /* infinity or NaN; value of *ex is unspecified */ 55f9f848faSopenharmony_ci break; 56f9f848faSopenharmony_ci default: /* normal */ 57f9f848faSopenharmony_ci *ex = u.bits.exp - 0x3ffe; 58f9f848faSopenharmony_ci u.bits.exp = 0x3ffe; 59f9f848faSopenharmony_ci break; 60f9f848faSopenharmony_ci } 61f9f848faSopenharmony_ci return (u.e); 62f9f848faSopenharmony_ci} 63