Method execute

src/dsql/ExprNodes.cpp:1971–2052

}

dsc* ArithmeticNode::execute(thread_db* tdbb, Request* request) const
{
	impure_value* const impure = request->getImpure<impure_value>(impureOffset);

	request->req_flags &= ~req_null;

	// Evaluate arguments.  If either is null, result is null, but in
	// any case, evaluate both, since some expressions may later depend
	// on mappings which are developed here

	const dsc* desc1 = EVL_expr(tdbb, request, arg1);
	const ULONG flags = request->req_flags;
	request->req_flags &= ~req_null;

	const dsc* desc2 = EVL_expr(tdbb, request, arg2);

	// restore saved NULL state

	if (flags & req_null)
		request->req_flags |= req_null;

	if (request->req_flags & req_null)
		return NULL;

	EVL_make_value(tdbb, desc1, impure);

	if (dialect1)	// dialect-1 semantics
	{
		switch (blrOp)
		{
			case blr_add:
			case blr_subtract:
				return add(tdbb, desc2, impure, this, blrOp);

			case blr_divide:
			{
				const double divisor = MOV_get_double(tdbb, desc2);

				if (divisor == 0)
				{
					ERR_post(Arg::Gds(isc_arith_except) <<
							 Arg::Gds(isc_exception_float_divide_by_zero));
				}

				impure->vlu_misc.vlu_double = MOV_get_double(tdbb, desc1) / divisor;

				if (std::isinf(impure->vlu_misc.vlu_double))
				{
					ERR_post(Arg::Gds(isc_arith_except) <<
							 Arg::Gds(isc_exception_float_overflow));
				}

				impure->vlu_desc.dsc_dtype = DEFAULT_DOUBLE;
				impure->vlu_desc.dsc_length = sizeof(double);
				impure->vlu_desc.dsc_address = (UCHAR*) &impure->vlu_misc;

				return &impure->vlu_desc;
			}