libjava/java/lang/s_fabs.c

   1
   2 /* @(#)s_fabs.c 5.1 93/09/24 */
   3 /*
   4  * ====================================================
   5  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   6  *
   7  * Developed at SunPro, a Sun Microsystems, Inc. business.
   8  * Permission to use, copy, modify, and distribute this
   9  * software is freely granted, provided that this notice
  10  * is preserved.
  11  * ====================================================
  12  */
  13
  14 /*
  15 FUNCTION
  16        <<fabs>>, <<fabsf>>---absolute value (magnitude)
  17 INDEX
  18         fabs
  19 INDEX
  20         fabsf
  21
  22 ANSI_SYNOPSIS
  23         #include <math.h>
  24        double fabs(double <[x]>);
  25        float fabsf(float <[x]>);
  26
  27 TRAD_SYNOPSIS
  28         #include <math.h>
  29        double fabs(<[x]>)
  30        double <[x]>;
  31
  32        float fabsf(<[x]>)
  33        float <[x]>;
  34
  35 DESCRIPTION
  36 <<fabs>> and <<fabsf>> calculate
  37 @tex
  38 $|x|$,
  39 @end tex
  40 the absolute value (magnitude) of the argument <[x]>, by direct
  41 manipulation of the bit representation of <[x]>.
  42
  43 RETURNS
  44 The calculated value is returned.  No errors are detected.
  45
  46 PORTABILITY
  47 <<fabs>> is ANSI.
  48 <<fabsf>> is an extension.
  49
  50 */
  51
  52 /*
  53  * fabs(x) returns the absolute value of x.
  54  */
  55
  56 #include "fdlibm.h"
  57
  58 #ifndef _DOUBLE_IS_32BITS
  59
  60 #ifdef __STDC__
  61         double fabs(double x)
  62 #else
  63         double fabs(x)
  64         double x;
  65 #endif
  66 {
  67         uint32_t high;
  68         GET_HIGH_WORD(high,x);
  69         SET_HIGH_WORD(x,high&0x7fffffff);
  70         return x;
  71 }
  72
  73 #endif /* _DOUBLE_IS_32BITS */