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

 * Special i387 version.

 * 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: $";

#endif

#include <errno.h>

#include <math.h>

#include <math-barriers.h>

#include <math_private.h>

#include <float.h>

float __nexttowardf(float x, long double y)

{

	int32_t hx,ix,iy;

	uint32_t hy,ly,esy;

	GET_FLOAT_WORD(hx,x);

	GET_LDOUBLE_WORDS(esy,hy,ly,y);

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

	iy = esy&0x7fff;		/* |y| */

	/* Intel's extended format has the normally implicit 1 explicit

	   present.  Sigh!  */

	if((ix>0x7f800000) ||			/* x is nan */

	   (iy>=0x7fff&&(((hy&0x7fffffff)|ly)!=0))) /* y is nan */

	   return x+y;

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

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

	    float u;

	    SET_FLOAT_WORD(x,((esy&0x8000)<<16)|1);/* return +-minsub*/

	    u = math_opt_barrier (x);

	    u = u * u;

	    math_force_eval (u);		/* raise underflow flag */

	    return x;

	}

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

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

		hx -= 1;

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

		hx += 1;

	    }

	} else {				/* x < 0 */

	    if(x < y) {				/* x -= ulp */

		hx -= 1;

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

		hx += 1;

	    }

	}

	hy = hx&0x7f800000;

	if(hy>=0x7f800000) {

	  float u = x+x;			/* overflow  */

	  math_force_eval (u);

	  __set_errno (ERANGE);

	}

	if(hy<0x00800000) {

	    float u = x*x;			/* underflow */

	    math_force_eval (u);		/* raise underflow flag */

	    __set_errno (ERANGE);

	}

	SET_FLOAT_WORD(x,hx);

	return x;

}

weak_alias (__nexttowardf, nexttowardf)