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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:
        		case _FpRoundNearest:
			// ....
        		break;

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

    	switch(ieee->Precision)
    {
        case \_FpPrecision24:
        		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
   ...
}