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/* s_floorf.c -- float version of s_floor.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_floorf.c,v 1.2 1995/05/30 05:49:40 rgrimes Exp $";
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#endif
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/*
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 * floorf(x)
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 * Return x rounded toward -inf to integral value
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 * Method:
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 *      Bit twiddling.
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 * Exception:
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 *      Inexact flag raised if x not equal to floorf(x).
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 */
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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static const float huge = 1.0e30;
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#else
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static float huge = 1.0e30;
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#endif
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#ifdef __STDC__
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        float floorf(float x)
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#else
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        float floorf(x)
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        float x;
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#endif
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{
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        int32_t i0,j0;
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        u_int32_t i;
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        GET_FLOAT_WORD(i0,x);
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        j0 = ((i0>>23)&0xff)-0x7f;
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        if(j0<23) {
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            if(j0<0) {  /* raise inexact if x != 0 */
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                if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
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                    if(i0>=0) {i0=0;}
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                    else if((i0&0x7fffffff)!=0)
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                        { i0=0xbf800000;}
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                }
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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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                if(huge+x>(float)0.0) { /* raise inexact flag */
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                    if(i0<0) i0 += (0x00800000)>>j0;
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                    i0 &= (~i);
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                }
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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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        return x;
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}