xref: /freebsd/lib/msun/src/s_ceilf.c (revision 01ded8b942effbbb4d9225c4227f264e499e9698)
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 #include <sys/cdefs.h>
17 __FBSDID("$FreeBSD$");
18 
19 #include "math.h"
20 #include "math_private.h"
21 
22 static const float huge = 1.0e30;
23 
24 float
25 ceilf(float x)
26 {
27 	int32_t i0,j0;
28 	u_int32_t i;
29 
30 	GET_FLOAT_WORD(i0,x);
31 	j0 = ((i0>>23)&0xff)-0x7f;
32 	if(j0<23) {
33 	    if(j0<0) { 	/* raise inexact if x != 0 */
34 		if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
35 		    if(i0<0) {i0=0x80000000;}
36 		    else if(i0!=0) { i0=0x3f800000;}
37 		}
38 	    } else {
39 		i = (0x007fffff)>>j0;
40 		if((i0&i)==0) return x; /* x is integral */
41 		if(huge+x>(float)0.0) {	/* raise inexact flag */
42 		    if(i0>0) i0 += (0x00800000)>>j0;
43 		    i0 &= (~i);
44 		}
45 	    }
46 	} else {
47 	    if(j0==0x80) return x+x;	/* inf or NaN */
48 	    else return x;		/* x is integral */
49 	}
50 	SET_FLOAT_WORD(x,i0);
51 	return x;
52 }
53