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      1 /* s_ceilf.c -- float version of s_ceil.c.
      2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian (at) 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 #if defined(LIBM_SCCS) && !defined(lint)
     18 __RCSID("$NetBSD: s_ceilf.c,v 1.8 2008/04/25 22:21:53 christos Exp $");
     19 #endif
     20 
     21 #include "math.h"
     22 #include "math_private.h"
     23 
     24 static const float huge = 1.0e30;
     25 
     26 float
     27 ceilf(float x)
     28 {
     29 	int32_t i0,jj0;
     30 	u_int32_t i;
     31 
     32 	GET_FLOAT_WORD(i0,x);
     33 	jj0 = ((i0>>23)&0xff)-0x7f;
     34 	if(jj0<23) {
     35 	    if(jj0<0) { 	/* raise inexact if x != 0 */
     36 		if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
     37 		    if(i0<0) {i0=0x80000000;}
     38 		    else if(i0!=0) { i0=0x3f800000;}
     39 		}
     40 	    } else {
     41 		i = (0x007fffff)>>jj0;
     42 		if((i0&i)==0) return x; /* x is integral */
     43 		if(huge+x>(float)0.0) {	/* raise inexact flag */
     44 		    if(i0>0) i0 += (0x00800000)>>jj0;
     45 		    i0 &= (~i);
     46 		}
     47 	    }
     48 	} else {
     49 	    if(jj0==0x80) return x+x;	/* inf or NaN */
     50 	    else return x;		/* x is integral */
     51 	}
     52 	SET_FLOAT_WORD(x,i0);
     53 	return x;
     54 }
     55