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/* s_floorf.c -- float version of s_floor.c.

 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.

 */

/*

 * ====================================================

 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.

 *

 * Developed at SunPro, a Sun Microsystems, Inc. business.

 * Permission to use, copy, modify, and distribute this

 * software is freely granted, provided that this notice

 * is preserved.

 * ====================================================

 */

#if defined(LIBM_SCCS) && !defined(lint)

static char rcsid[] = "$NetBSD: s_floorf.c,v 1.4 1995/05/10 20:47:22 jtc Exp $";

#endif

/*

 * floorf(x)

 * Return x rounded toward -inf to integral value

 * Method:

 *      Bit twiddling.

 * Exception:

 *      Inexact flag raised if x not equal to floorf(x).

 */

#include "math.h"

#include "math_private.h"

#ifdef __STDC__

static const float huge = 1.0e30;

#else

static float huge = 1.0e30;

#endif

#ifdef __STDC__

        float __floorf(float x)

#else

        float __floorf(x)

        float x;

#endif

{

        int32_t i0,j0;

        u_int32_t i;

        GET_FLOAT_WORD(i0,x);

        j0 = ((i0>>23)&0xff)-0x7f;

        if(j0<23) {

            if(j0<0) {   /* raise inexact if x != 0 */

                if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */

                    if(i0>=0) {i0=0;}

                    else if((i0&0x7fffffff)!=0)

                        { i0=0xbf800000;}

                }

            } else {

                i = (0x007fffff)>>j0;

                if((i0&i)==0) return x; /* x is integral */

                if(huge+x>(float)0.0) { /* raise inexact flag */

                    if(i0<0) i0 += (0x00800000)>>j0;

                    i0 &= (~i);

                }

            }

        } else {

            if(j0==0x80) return x+x;    /* inf or NaN */

            else return x;              /* x is integral */

        }

        SET_FLOAT_WORD(x,i0);

        return x;

}

weak_alias (__floorf, floorf)