sysdeps/libm-ieee754/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 #if defined(LIBM_SCCS) && !defined(lint)
  17 static char rcsid[] = "$NetBSD: s_ceilf.c,v 1.4 1995/05/10 20:46:55 jtc Exp $";
  18 #endif
  19
  20 #include "math.h"
  21 #include "math_private.h"
  22
  23 #ifdef __STDC__
  24 static const float huge = 1.0e30;
  25 #else
  26 static float huge = 1.0e30;
  27 #endif
  28
  29 #ifdef __STDC__
  30         float __ceilf(float x)
  31 #else
  32         float __ceilf(x)
  33         float x;
  34 #endif
  35 {
  36         int32_t i0,j0;
  37         u_int32_t i;
  38
  39         GET_FLOAT_WORD(i0,x);
  40         j0 = ((i0>>23)&0xff)-0x7f;
  41         if(j0<23) {
  42             if(j0<0) {  /* raise inexact if x != 0 */
  43                 if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */
  44                     if(i0<0) {i0=0x80000000;}
  45                     else if(i0!=0) { i0=0x3f800000;}
  46                 }
  47             } else {
  48                 i = (0x007fffff)>>j0;
  49                 if((i0&i)==0) return x; /* x is integral */
  50                 if(huge+x>(float)0.0) { /* raise inexact flag */
  51                     if(i0>0) i0 += (0x00800000)>>j0;
  52                     i0 &= (~i);
  53                 }
  54             }
  55         } else {
  56             if(j0==0x80) return x+x;    /* inf or NaN */
  57             else return x;              /* x is integral */
  58         }
  59         SET_FLOAT_WORD(x,i0);
  60         return x;
  61 }
  62 weak_alias (__ceilf, ceilf)