77 lines
2.6 KiB
C
77 lines
2.6 KiB
C
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/* $NetBSD: fpu_getexp.c,v 1.1 1995/11/03 04:47:11 briggs Exp $ */
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/*
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* Copyright (c) 1995 Ken Nakata
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)fpu_getexp.c 10/8/95
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*/
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#include <sys/types.h>
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#include "fpu_emulate.h"
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struct fpn *
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fpu_getexp(fe)
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struct fpemu *fe;
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{
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struct fpn *fp = &fe->fe_f2;
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fe->fe_fpsr &= ~FPSR_EXCP; /* clear all exceptions */
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if (fp->fp_class == FPC_INF) {
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fp = fpu_newnan(fe);
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fe->fe_fpsr |= FPSR_OPERR;
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} else if (fp->fp_class == FPC_NUM) { /* a number */
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fpu_explode(fe, &fe->fe_f3, FTYPE_LNG, &fp->fp_exp);
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fp = &fe->fe_f3;
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} else if (fp->fp_class == FPC_SNAN) { /* signaling NaN */
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fe->fe_fpsr |= FPSR_SNAN;
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} /* else if fp == zero or fp == quiet NaN, return itself */
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return fp;
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}
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struct fpn *
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fpu_getman(fe)
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struct fpemu *fe;
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{
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struct fpn *fp = &fe->fe_f2;
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fe->fe_fpsr &= ~FPSR_EXCP; /* clear all exceptions */
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if (fp->fp_class == FPC_INF) {
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fp = fpu_newnan(fe);
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fe->fe_fpsr |= FPSR_OPERR;
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} else if (fp->fp_class == FPC_NUM) { /* a number */
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fp->fp_exp = 0;
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} else if (fp->fp_class == FPC_SNAN) { /* signaling NaN */
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fe->fe_fpsr |= FPSR_SNAN;
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} /* else if fp == zero or fp == quiet NaN, return itself */
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return fp;
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}
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