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/* sf_nextafter.c -- float version of s_nextafter.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.

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

 */

#include "fdlibm.h"

#ifdef __STDC__

        float nextafterf(float x, float y)

#else

        float nextafterf(x,y)

        float x,y;

#endif

{

        __int32_t       hx,hy,ix,iy;

        GET_FLOAT_WORD(hx,x);

        GET_FLOAT_WORD(hy,y);

        ix = hx&0x7fffffff;             /* |x| */

        iy = hy&0x7fffffff;             /* |y| */

        if(FLT_UWORD_IS_NAN(ix) ||

           FLT_UWORD_IS_NAN(iy))

           return x+y;

        if(x==y) return x;              /* x=y, return x */

        if(FLT_UWORD_IS_ZERO(ix)) {             /* x == 0 */

            SET_FLOAT_WORD(x,(hy&0x80000000)|FLT_UWORD_MIN);

            y = x*x;

            if(y==x) return y; else return x;   /* raise underflow flag */

        }

        if(hx>=0) {                              /* x > 0 */

            if(hx>hy) {                         /* x > y, x -= ulp */

                hx -= 1;

            } else {                            /* x < y, x += ulp */

                hx += 1;

            }

        } else {                                /* x < 0 */

            if(hy>=0||hx>hy){                    /* x < y, x -= ulp */

                hx -= 1;

            } else {                            /* x > y, x += ulp */

                hx += 1;

            }

        }

        hy = hx&0x7f800000;

        if(hy>FLT_UWORD_MAX) return x+x;        /* overflow  */

        if(hy<0x00800000) {             /* underflow */

            y = x*x;

            if(y!=x) {          /* raise underflow flag */

                SET_FLOAT_WORD(y,hx);

                return y;

            }

        }

        SET_FLOAT_WORD(x,hx);

        return x;

}

#ifdef _DOUBLE_IS_32BITS

#ifdef __STDC__

        double nextafter(double x, double y)

#else

        double nextafter(x,y)

        double x,y;

#endif

{

        return (double) nextafterf((float) x, (float) x);

}

#endif /* defined(_DOUBLE_IS_32BITS) */