xref: /freebsd/lib/msun/src/s_ceilf.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #include "math.h"
18 #include "math_private.h"
19 
20 static const float huge = 1.0e30;
21 
22 float
23 ceilf(float x)
24 {
25 	int32_t i0,j0;
26 	u_int32_t i;
27 
28 	GET_FLOAT_WORD(i0,x);
29 	j0 = ((i0>>23)&0xff)-0x7f;
30 	if(j0<23) {
31 	    if(j0<0) { 	/* raise inexact if x != 0 */
32 		if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
33 		    if(i0<0) {i0=0x80000000;}
34 		    else if(i0!=0) { i0=0x3f800000;}
35 		}
36 	    } else {
37 		i = (0x007fffff)>>j0;
38 		if((i0&i)==0) return x; /* x is integral */
39 		if(huge+x>(float)0.0) {	/* raise inexact flag */
40 		    if(i0>0) i0 += (0x00800000)>>j0;
41 		    i0 &= (~i);
42 		}
43 	    }
44 	} else {
45 	    if(j0==0x80) return x+x;	/* inf or NaN */
46 	    else return x;		/* x is integral */
47 	}
48 	SET_FLOAT_WORD(x,i0);
49 	return x;
50 }
51