rom/mathffp/sptst.c

   1 /*
   2     Copyright © 1995-2004, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include "mathffp_intern.h"
   7
   8 /*
   9     FUNCTION
  10         Compare a ffp-number against zero.
  11
  12     RESULT
  13         <code>
  14         +1 : fnum > 0.0
  15          0 : fnum = 0.0
  16         -1 : fnum < 0.0
  17
  18         Flags:
  19           zero     : result is zero
  20           negative : result is negative
  21           overflow : 0
  22         </code>
  23
  24     NOTES
  25
  26     EXAMPLE
  27
  28     BUGS
  29
  30     SEE ALSO
  31
  32
  33     INTERNALS
  34       ALGORITHM:
  35         Sign is negative: return -1
  36         fnum == 0       : return 0
  37         Otherwise       : return 1
  38
  39     HISTORY
  40 */
  41
  42 AROS_LH1(LONG, SPTst,
  43     AROS_LHA(float, fnum, D1),
  44     struct LibHeader *, MathBase, 8, Mathffp
  45 )
  46 {
  47     AROS_LIBFUNC_INIT
  48     /* fnum1 is negative */
  49     if ((char) fnum < 0)
  50     {
  51         SetSR(Negative_Bit, Zero_Bit | Overflow_Bit | Negative_Bit);
  52         return -1;
  53     }
  54
  55     /* fnum1 is zero */
  56     if (0 == fnum)
  57     {
  58         SetSR(Zero_Bit, Zero_Bit | Overflow_Bit | Negative_Bit);
  59         return 0;
  60     }
  61
  62     /* fnum1 is positive */
  63     SetSR(0, Zero_Bit | Overflow_Bit | Negative_Bit );
  64
  65     return 1;
  66
  67     AROS_LIBFUNC_EXIT
  68 }