1 /* @(#)s_ceil.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 * ====================================================
12 * $NetBSD: s_ceil.c,v 1.11 2002/05/26 22:01:54 wiz Exp $
13 * $DragonFly: src/lib/libm/src/s_ceil.c,v 1.1 2005/07/26 21:15:20 joerg Exp $
18 * Return x rounded toward -inf to integral value
22 * Inexact flag raised if x not equal to ceil(x).
26 #include "math_private.h"
28 static const double huge
= 1.0e300
;
35 EXTRACT_WORDS(i0
,i1
,x
);
36 j0
= ((i0
>>20)&0x7ff)-0x3ff;
38 if(j0
<0) { /* raise inexact if x != 0 */
39 if(huge
+x
>0.0) {/* return 0*sign(x) if |x|<1 */
40 if(i0
<0) {i0
=0x80000000;i1
=0;}
41 else if((i0
|i1
)!=0) { i0
=0x3ff00000;i1
=0;}
45 if(((i0
&i
)|i1
)==0) return x
; /* x is integral */
46 if(huge
+x
>0.0) { /* raise inexact flag */
47 if(i0
>0) i0
+= (0x00100000)>>j0
;
52 if(j0
==0x400) return x
+x
; /* inf or NaN */
53 else return x
; /* x is integral */
55 i
= ((u_int32_t
)(0xffffffff))>>(j0
-20);
56 if((i1
&i
)==0) return x
; /* x is integral */
57 if(huge
+x
>0.0) { /* raise inexact flag */
61 j
= i1
+ (1<<(52-j0
));
62 if(j
<i1
) i0
+=1; /* got a carry */
69 INSERT_WORDS(x
,i0
,i1
);