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 fp_usingSEH()
{
      {
  /* ...
      */
  double a = 1e-40, b, c = 0.1;
       float x = 0, y;
       unsigned int rv ;

      unmask_fp();

      \_try
      {
          // Store into y is inexact and underflows:
          y = a;

          // divide by zero operation
          b = y / x;

          // inexact
          c = sin(30) * a;
       }

       \_except (_fpieee_flt (GetExceptionCode(), GetExceptionInformation(), fpieee_handler))
       {
               printf ("fpieee_handler: EXCEPTION_EXECUTE_HANDLER");
        }

        ...
}

void unmask_fpsr(void)
{
     unsigned int u;
     unsigned int control_word;
     \_controlfp_s(&control_word, 0, 0);
     u = control_word & \~(_EM_INVALID \| \_EM_DENORMAL \| \_EM_ZERODIVIDE
              \| \_EM_OVERFLOW \| \_EM_UNDERFLOW \| \_EM_INEXACT);
      \_controlfp_s( &control_word, u, \_MCW_EM);
      return ;
}

int fpieee_handler (_FPIEEE_RECORD \*ieee)
{
    // ...

    switch(ieee->RoundingMode)
    {
        case \_FpRoundNearest:
        // ....
        break;

        /\* Other RMs include \_FpRoundMinusInfinity, \_FpRoundPlusInfinity, \_FpRoundChopped \*/
        // ....
    }

    switch(ieee->Precision)
    {
        case \_FpPrecision24:
        // ....
       break;

       /\* Other Ps include \_FpPrecision53*/
       // ....
   }

   switch(ieee->Operation)
   {
      case \_FpCodeAdd:
      // ...
      break;

      /\* Other Ops include \_FpCodeSubtract, \_FpCodeMultiply, \_FpCodeDivide, \_FpCodeSquareRoot, \_FpCodeCompare, \_FpCodeConvert, \_FpCodeConvertTrunc \*/
      // ....

   }

   // process the bitmap ieee->Cause
   // process the bitmap ieee->Enable
   // process the bitmap ieee->Status
   // process the Operand ieee->Operand1, evaluate format and Value
   // process the Operand ieee->Operand2, evaluate format and Value
   // process the Result ieee->Result, evaluate format and Value
   // the result should be set according to the operation specified in ieee->Cause and the result format as specified in ieee->Result
   // the Result set is based on the
   ...
}\\