xref: /freebsd/lib/msun/src/s_ceilf.c (revision 17ee9d00bc1ae1e598c38f25826f861e4bc6c3ce)
1 /* s_ceilf.c -- float version of s_ceil.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 #ifndef lint
17 static char rcsid[] = "$Id: s_ceilf.c,v 1.2 1994/08/18 23:06:30 jtc Exp $";
18 #endif
19 
20 #include "math.h"
21 #include "math_private.h"
22 
23 #ifdef __STDC__
24 static const float huge = 1.0e30;
25 #else
26 static float huge = 1.0e30;
27 #endif
28 
29 #ifdef __STDC__
30 	float ceilf(float x)
31 #else
32 	float ceilf(x)
33 	float x;
34 #endif
35 {
36 	int32_t i0,j0;
37 	u_int32_t i;
38 
39 	GET_FLOAT_WORD(i0,x);
40 	j0 = ((i0>>23)&0xff)-0x7f;
41 	if(j0<23) {
42 	    if(j0<0) { 	/* raise inexact if x != 0 */
43 		if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
44 		    if(i0<0) {i0=0x80000000;}
45 		    else if(i0!=0) { i0=0x3f800000;}
46 		}
47 	    } else {
48 		i = (0x007fffff)>>j0;
49 		if((i0&i)==0) return x; /* x is integral */
50 		if(huge+x>(float)0.0) {	/* raise inexact flag */
51 		    if(i0>0) i0 += (0x00800000)>>j0;
52 		    i0 &= (~i);
53 		}
54 	    }
55 	} else {
56 	    if(j0==0x80) return x+x;	/* inf or NaN */
57 	    else return x;		/* x is integral */
58 	}
59 	SET_FLOAT_WORD(x,i0);
60 	return x;
61 }
62