Method add

src/dsql/ExprNodes.cpp:2056–2135

Add (or subtract) the contents of a descriptor to value block, with dialect-1 semantics. This function can be removed when dialect-3 becomes the lowest supported dialect. (Version 7.0?)

// Add (or subtract) the contents of a descriptor to value block, with dialect-1 semantics.
// This function can be removed when dialect-3 becomes the lowest supported dialect. (Version 7.0?)
dsc* ArithmeticNode::add(thread_db* tdbb, const dsc* desc, impure_value* value, const ValueExprNode* node,
	const UCHAR blrOp)
{
	const ArithmeticNode* arithmeticNode = nodeAs<ArithmeticNode>(node);

#ifdef DEV_BUILD
	const SubQueryNode* subQueryNode = nodeAs<SubQueryNode>(node);
	fb_assert(
		(arithmeticNode && arithmeticNode->dialect1 &&
			(arithmeticNode->blrOp == blr_add || arithmeticNode->blrOp == blr_subtract)) ||
		nodeIs<AggNode>(node) ||
		(subQueryNode && (subQueryNode->blrOp == blr_total || subQueryNode->blrOp == blr_average)));
#endif

	dsc* const result = &value->vlu_desc;

	// Handle date arithmetic

	if (node->nodFlags & FLAG_DATE)
	{
		fb_assert(arithmeticNode);
		return arithmeticNode->addDateTime(tdbb, desc, value);
	}

	// Handle decimal arithmetic

	if (node->nodFlags & FLAG_DECFLOAT)
	{
		const Decimal128 d1 = MOV_get_dec128(tdbb, desc);
		const Decimal128 d2 = MOV_get_dec128(tdbb, &value->vlu_desc);

		DecimalStatus decSt = tdbb->getAttachment()->att_dec_status;
		value->vlu_misc.vlu_dec128 = (blrOp == blr_subtract) ? d2.sub(decSt, d1) : d1.add(decSt, d2);

		result->dsc_dtype = dtype_dec128;
		result->dsc_length = sizeof(Decimal128);
		result->dsc_scale = 0;
		result->dsc_sub_type = 0;
		result->dsc_address = (UCHAR*) &value->vlu_misc.vlu_dec128;

		return result;
	}

	// Handle floating arithmetic

	if (node->nodFlags & FLAG_DOUBLE)
	{
		const double d1 = MOV_get_double(tdbb, desc);
		const double d2 = MOV_get_double(tdbb, &value->vlu_desc);

		value->vlu_misc.vlu_double = (blrOp == blr_subtract) ? d2 - d1 : d1 + d2;

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

		result->dsc_dtype = DEFAULT_DOUBLE;
		result->dsc_length = sizeof(double);
		result->dsc_scale = 0;