workbench/libs/mathieeedoubbas/ieeedpabs.c

   1 /*
   2     Copyright © 1995-2003, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include "mathieeedoubbas_intern.h"
   7
   8 /*****************************************************************************
   9
  10     NAME */
  11
  12         AROS_LHQUAD1(double, IEEEDPAbs,
  13
  14 /*  SYNOPSIS */
  15         AROS_LHAQUAD(double, y, D0, D1),
  16
  17 /*  LOCATION */
  18         struct MathIeeeDoubBasBase *, MathIeeeDoubBasBase, 9, MathIeeeDoubBas)
  19
  20 /*  FUNCTION
  21         Calculate the absolute value of the given IEEE double precision
  22         floating point number
  23
  24     INPUTS
  25
  26     RESULT
  27         absolute value of y
  28
  29         Flags:
  30           zero     : result is zero
  31           negative : 0
  32           overflow : 0
  33
  34     BUGS
  35
  36     INTERNALS
  37         ALGORITHM:
  38         set the sign-bit to zero
  39
  40 *****************************************************************************/
  41 {
  42     AROS_LIBFUNC_INIT
  43
  44     QUAD * Qy = (QUAD *)&y;
  45
  46     /*if (0 == (*Qy)) */
  47     if (is_eqC((*Qy),0,0))
  48     {
  49         /* value is 0 -> set the Zero Flag */
  50         SetSR( Zero_Bit, Zero_Bit | Overflow_Bit | Negative_Bit);
  51     }
  52     else
  53     {
  54         /* set the sign-bit to zero */
  55         /* (*Qy) &= (IEEEDPMantisse_Mask | IEEEDPExponent_Mask) */
  56         AND64QC
  57         (
  58             (*Qy),
  59             (IEEEDPMantisse_Mask_Hi | IEEEDPExponent_Mask_Hi),
  60             (IEEEDPMantisse_Mask_Lo | IEEEDPExponent_Mask_Lo)
  61         );
  62         SetSR(0, Zero_Bit | Overflow_Bit | Negative_Bit );
  63     }
  64
  65     return y;
  66
  67     AROS_LIBFUNC_EXIT
  68 }