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