1 /* @(#)s_nextafter.c 5.1 93/09/24 */
3 * ====================================================
4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6 * Developed at SunPro, a Sun Microsystems, Inc. business.
7 * Permission to use, copy, modify, and distribute this
8 * software is freely granted, provided that this notice
10 * ====================================================
15 * return the next machine floating-point number of x in the
17 * This is for machines which use the same binary type for double and
25 #include "math_private.h"
28 nexttowardf(float x
, long double y
)
34 EXTRACT_WORDS(hy
,ly
,y
);
35 ix
= hx
&0x7fffffff; /* |x| */
36 iy
= hy
&0x7fffffff; /* |y| */
38 if((ix
>0x7f800000) || /* x is nan */
39 ((iy
>=0x7ff00000)&&((iy
-0x7ff00000)|ly
)!=0)) /* y is nan */
41 if((long double) x
==y
) return y
; /* x=y, return y */
42 if(ix
==0) { /* x == 0 */
44 SET_FLOAT_WORD(x
,(u_int32_t
)(hy
&0x80000000)|1);/* return +-minsub*/
46 u
= u
* u
; /* raise underflow flag */
49 if(hx
>=0) { /* x > 0 */
50 if(hy
<0||(ix
>>23)>(iy
>>20)-0x380
51 || ((ix
>>23)==(iy
>>20)-0x380
52 && (ix
&0x7fffff)>(((hy
<<3)|(ly
>>29))&0x7fffff))) /* x > y, x -= ulp */
54 else /* x < y, x += ulp */
57 if(hy
>=0||(ix
>>23)>(iy
>>20)-0x380
58 || ((ix
>>23)==(iy
>>20)-0x380
59 && (ix
&0x7fffff)>(((hy
<<3)|(ly
>>29))&0x7fffff))) /* x < y, x -= ulp */
61 else /* x > y, x += ulp */
66 x
= x
+x
; /* overflow */
70 volatile float u
= x
*x
; /* underflow */