1 /* $NetBSD: fpu_getexp.c,v 1.4 2009/03/14 15:36:09 dsl Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Ken Nakata 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the author nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)fpu_getexp.c 10/8/95 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: fpu_getexp.c,v 1.4 2009/03/14 15:36:09 dsl Exp $"); 36 37 #include <sys/types.h> 38 39 #include "fpu_emulate.h" 40 41 struct fpn * 42 fpu_getexp(struct fpemu *fe) 43 { 44 struct fpn *fp = &fe->fe_f2; 45 46 fe->fe_fpsr &= ~FPSR_EXCP; /* clear all exceptions */ 47 48 if (fp->fp_class == FPC_INF) { 49 fp = fpu_newnan(fe); 50 fe->fe_fpsr |= FPSR_OPERR; 51 } else if (fp->fp_class == FPC_NUM) { /* a number */ 52 fpu_explode(fe, &fe->fe_f3, FTYPE_LNG, &fp->fp_exp); 53 fp = &fe->fe_f3; 54 } else if (fp->fp_class == FPC_SNAN) { /* signaling NaN */ 55 fe->fe_fpsr |= FPSR_SNAN; 56 } /* else if fp == zero or fp == quiet NaN, return itself */ 57 return fp; 58 } 59 60 struct fpn * 61 fpu_getman(struct fpemu *fe) 62 { 63 struct fpn *fp = &fe->fe_f2; 64 65 fe->fe_fpsr &= ~FPSR_EXCP; /* clear all exceptions */ 66 67 if (fp->fp_class == FPC_INF) { 68 fp = fpu_newnan(fe); 69 fe->fe_fpsr |= FPSR_OPERR; 70 } else if (fp->fp_class == FPC_NUM) { /* a number */ 71 fp->fp_exp = 0; 72 } else if (fp->fp_class == FPC_SNAN) { /* signaling NaN */ 73 fe->fe_fpsr |= FPSR_SNAN; 74 } /* else if fp == zero or fp == quiet NaN, return itself */ 75 return fp; 76 } 77 78