1/* s_nextafterf.c -- float version of s_nextafter.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
16#if defined(LIBM_SCCS) && !defined(lint)
17static char rcsid[] = "$NetBSD: s_nextafterf.c,v 1.4 1995/05/10 20:48:01 jtc Exp $";
18#endif
19
20#include "math.h"
21#include "math_private.h"
22#include <float.h>
23
24#ifdef __STDC__
25	float __nextafterf(float x, float y)
26#else
27	float __nextafterf(x,y)
28	float x,y;
29#endif
30{
31	int32_t hx,hy,ix,iy;
32
33	GET_FLOAT_WORD(hx,x);
34	GET_FLOAT_WORD(hy,y);
35	ix = hx&0x7fffffff;		/* |x| */
36	iy = hy&0x7fffffff;		/* |y| */
37
38	if((ix>0x7f800000) ||   /* x is nan */
39	   (iy>0x7f800000))     /* y is nan */
40	   return x+y;
41	if(x==y) return y;		/* x=y, return y */
42	if(ix==0) {				/* x == 0 */
43	    SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */
44	    y = x*x;
45	    if(y==x) return y; else return x;	/* raise underflow flag */
46	}
47	if(hx>=0) {				/* x > 0 */
48	    if(hx>hy) {				/* x > y, x -= ulp */
49		hx -= 1;
50	    } else {				/* x < y, x += ulp */
51		hx += 1;
52	    }
53	} else {				/* x < 0 */
54	    if(hy>=0||hx>hy){			/* x < y, x -= ulp */
55		hx -= 1;
56	    } else {				/* x > y, x += ulp */
57		hx += 1;
58	    }
59	}
60	hy = hx&0x7f800000;
61	if(hy>=0x7f800000) {
62	  x = x+x;	/* overflow  */
63	  if (FLT_EVAL_METHOD != 0)
64	    asm ("" : "=m"(x) : "m"(x));
65	  return x;	/* overflow  */
66	}
67	if(hy<0x00800000) {		/* underflow */
68	    y = x*x;
69	    if(y!=x) {		/* raise underflow flag */
70	        SET_FLOAT_WORD(y,hx);
71		return y;
72	    }
73	}
74	SET_FLOAT_WORD(x,hx);
75	return x;
76}
77weak_alias (__nextafterf, nextafterf)
78