contrib/openbsd_libm/src/s_ceilf.c

   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,jj0;
  25         u_int32_t i;
  26
  27         GET_FLOAT_WORD(i0,x);
  28         jj0 = ((i0>>23)&0xff)-0x7f;
  29         if(jj0<23) {
  30             if(jj0<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)>>jj0;
  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)>>jj0;
  40                     i0 &= (~i);
  41                 }
  42             }
  43         } else {
  44             if(jj0==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 }