xref: /freebsd/lib/msun/src/s_ceilf.c (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
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[] = "$FreeBSD$";
18 #endif
19 
20 #include "math.h"
21 #include "math_private.h"
22 
23 static const float huge = 1.0e30;
24 
25 float
26 ceilf(float x)
27 {
28 	int32_t i0,j0;
29 	u_int32_t i;
30 
31 	GET_FLOAT_WORD(i0,x);
32 	j0 = ((i0>>23)&0xff)-0x7f;
33 	if(j0<23) {
34 	    if(j0<0) { 	/* raise inexact if x != 0 */
35 		if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
36 		    if(i0<0) {i0=0x80000000;}
37 		    else if(i0!=0) { i0=0x3f800000;}
38 		}
39 	    } else {
40 		i = (0x007fffff)>>j0;
41 		if((i0&i)==0) return x; /* x is integral */
42 		if(huge+x>(float)0.0) {	/* raise inexact flag */
43 		    if(i0>0) i0 += (0x00800000)>>j0;
44 		    i0 &= (~i);
45 		}
46 	    }
47 	} else {
48 	    if(j0==0x80) return x+x;	/* inf or NaN */
49 	    else return x;		/* x is integral */
50 	}
51 	SET_FLOAT_WORD(x,i0);
52 	return x;
53 }
54