workbench/libs/mathieeedoubtrans/ieeedpsinh.c

   1 /*
   2     Copyright © 1995-2003, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include "mathieeedoubtrans_intern.h"
   7
   8 /*
   9     FUNCTION
  10       Calculate the hyperbolic sine of the IEEE double precision number
  11
  12     RESULT
  13       IEEE double precision floating point number
  14
  15       flags:
  16         zero     : result is zero
  17         negative : result is negative
  18         overflow : result is too big for IEEE double precsion format
  19
  20     NOTES
  21
  22     EXAMPLE
  23
  24     BUGS
  25
  26     SEE ALSO
  27
  28     INTERNALS
  29       <code>
  30       sinh(x) = (1/2)*( e^x- e^(-x) )
  31
  32       sinh( |x| >=  18 ) = (1/2) * (e^x);
  33       </code>
  34
  35     HISTORY
  36 */
  37
  38 AROS_LHQUAD1(double, IEEEDPSinh,
  39     AROS_LHAQUAD(double, y, D0, D1),
  40     struct MathIeeeDoubTransBase *, MathIeeeDoubTransBase, 10, MathIeeeDoubTrans
  41 )
  42 {
  43     AROS_LIBFUNC_INIT
  44
  45     QUAD Res;
  46     QUAD y2;
  47
  48     /* y2 = y & (IEEEDPMantisse_Mask + IEEEDPExponent_Mask); */
  49     Set_Value64(y2, y);
  50     AND64QC
  51     (
  52         y2,
  53         (IEEEDPMantisse_Mask_Hi + IEEEDPExponent_Mask_Hi),
  54         (IEEEDPMantisse_Mask_Lo + IEEEDPExponent_Mask_Lo)
  55     );
  56
  57     if ( is_eqC(y, IEEEDPPInfty_Hi, IEEEDPPInfty_Lo))
  58     {
  59         SetSR(Overflow_Bit, Zero_Bit | Negative_Bit | Overflow_Bit);
  60         return y;
  61     }
  62
  63     /* sinh(-x) = -sinh(x) */
  64     Res = IEEEDPExp(y2);
  65
  66     if ( is_eqC(Res, IEEEDPPInfty_Hi, IEEEDPPInfty_Lo ))
  67     {
  68         SetSR(Overflow_Bit, Zero_Bit | Negative_Bit | Overflow_Bit);
  69         if ( is_lessSC(y, 0x0, 0x0))
  70         {
  71             OR64QC(Res, IEEEDPSign_Mask_Hi, IEEEDPSign_Mask_Lo );
  72         }
  73         return Res;
  74     }
  75
  76     if ( is_lessC(y2, 0x40320000, 0x0) )
  77     {
  78         QUAD One, ResTmp;
  79         Set_Value64C(One, one_Hi, one_Lo);
  80         ResTmp = IEEEDPDiv(One, Res);
  81         OR64QC(ResTmp, IEEEDPSign_Mask_Hi, IEEEDPSign_Mask_Lo);
  82
  83         Res = IEEEDPAdd(Res, ResTmp);
  84     }
  85     /* Res = Res / 2 */
  86     ADD64QC(Res, 0xFFF00000, 0x0);
  87
  88     /* at this point Res has to be positive to be valid */
  89     if ( is_leqSC(Res, 0x0, 0x0))
  90     {
  91         SetSR(Zero_Bit, Zero_Bit | Negative_Bit | Overflow_Bit);
  92         AND64QC(y, IEEEDPSign_Mask_Hi, IEEEDPSign_Mask_Lo);
  93         return y;
  94     }
  95
  96     if ( is_lessSC(y, 0x0, 0x0))
  97     {
  98         SetSR(Negative_Bit, Zero_Bit | Negative_Bit | Overflow_Bit);
  99         OR64QC(Res, IEEEDPSign_Mask_Hi, IEEEDPSign_Mask_Lo );
 100
 101         return Res;
 102     }
 103
 104     return Res;
 105
 106     AROS_LIBFUNC_EXIT
 107 }