xref: /freebsd/lib/msun/src/s_ceilf.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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 "math.h"
17 #include "math_private.h"
18 
19 static const float huge = 1.0e30;
20 
21 float
22 ceilf(float x)
23 {
24 	int32_t i0,j0;
25 	u_int32_t i;
26 
27 	GET_FLOAT_WORD(i0,x);
28 	j0 = ((i0>>23)&0xff)-0x7f;
29 	if(j0<23) {
30 	    if(j0<0) { 	/* raise inexact if x != 0 */
31 		if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
32 		    if(i0<0) {i0=0x80000000;}
33 		    else if(i0!=0) { i0=0x3f800000;}
34 		}
35 	    } else {
36 		i = (0x007fffff)>>j0;
37 		if((i0&i)==0) return x; /* x is integral */
38 		if(huge+x>(float)0.0) {	/* raise inexact flag */
39 		    if(i0>0) i0 += (0x00800000)>>j0;
40 		    i0 &= (~i);
41 		}
42 	    }
43 	} else {
44 	    if(j0==0x80) return x+x;	/* inf or NaN */
45 	    else return x;		/* x is integral */
46 	}
47 	SET_FLOAT_WORD(x,i0);
48 	return x;
49 }
50