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/* s_rintf.c -- float version of s_rint.c.
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 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
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 */
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/*
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 * ====================================================
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 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice
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 * is preserved.
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 * ====================================================
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 */
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#ifndef lint
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static char rcsid[] = "$\Id: s_rintf.c,v 1.3 1996/08/28 16:34:36 bde Exp $";
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#endif
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#include "math.h"
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#include "math_private.h"
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/*
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 * TWO23 is double instead of float to avoid a bug in gcc.  Without
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 * this, gcc thinks that TWO23[sx]+x and w-TWO23[sx] already have float
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 * precision and doesn't clip them to float precision when they are
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 * assigned and returned.
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 */
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#ifdef __STDC__
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static const double
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#else
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static double
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#endif
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TWO23[2]={
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  8.3886080000e+06, /* 0x4b000000 */
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 -8.3886080000e+06, /* 0xcb000000 */
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};
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#ifdef __STDC__
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        float rintf(float x)
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#else
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        float rintf(x)
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        float x;
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#endif
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{
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        int32_t i0,j0,sx;
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        u_int32_t i,i1;
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        float w,t;
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        GET_FLOAT_WORD(i0,x);
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        sx = (i0>>31)&1;
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        j0 = ((i0>>23)&0xff)-0x7f;
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        if(j0<23) {
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            if(j0<0) {
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                if((i0&0x7fffffff)==0) return x;
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                i1 = (i0&0x07fffff);
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                i0 &= 0xfff00000;
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                i0 |= ((i1|-i1)>>9)&0x400000;
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                SET_FLOAT_WORD(x,i0);
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                w = TWO23[sx]+x;
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                t =  w-TWO23[sx];
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                GET_FLOAT_WORD(i0,t);
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                SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
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                return t;
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            } else {
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                i = (0x007fffff)>>j0;
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                if((i0&i)==0) return x; /* x is integral */
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                i>>=1;
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                if((i0&i)!=0) i0 = (i0&(~i))|((0x100000)>>j0);
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            }
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        } else {
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            if(j0==0x80) return x+x;    /* inf or NaN */
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            else return x;              /* x is integral */
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        }
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        SET_FLOAT_WORD(x,i0);
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        w = TWO23[sx]+x;
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        return w-TWO23[sx];
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}