1 /* @(#)s_ceil.c 5.1 93/09/24 */
3 * ====================================================
4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6 * Developed at SunPro, a Sun Microsystems, Inc. business.
7 * Permission to use, copy, modify, and distribute this
8 * software is freely granted, provided that this notice
10 * ====================================================
13 #include <sys/cdefs.h>
14 __FBSDID("$FreeBSD$");
18 * Return x rounded toward -inf to integral value
22 * Inexact flag raised if x not equal to ceil(x).
28 #include "math_private.h"
30 static const double huge = 1.0e300;
37 EXTRACT_WORDS(i0,i1,x);
38 j0 = ((i0>>20)&0x7ff)-0x3ff;
40 if(j0<0) { /* raise inexact if x != 0 */
41 if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
42 if(i0<0) {i0=0x80000000;i1=0;}
43 else if((i0|i1)!=0) { i0=0x3ff00000;i1=0;}
47 if(((i0&i)|i1)==0) return x; /* x is integral */
48 if(huge+x>0.0) { /* raise inexact flag */
49 if(i0>0) i0 += (0x00100000)>>j0;
54 if(j0==0x400) return x+x; /* inf or NaN */
55 else return x; /* x is integral */
57 i = ((u_int32_t)(0xffffffff))>>(j0-20);
58 if((i1&i)==0) return x; /* x is integral */
59 if(huge+x>0.0) { /* raise inexact flag */
63 j = i1 + (1<<(52-j0));
64 if(j<i1) i0+=1; /* got a carry */
71 INSERT_WORDS(x,i0,i1);
75 #if LDBL_MANT_DIG == 53
76 __weak_reference(ceil, ceill);