Method genNegZero

src/dsql/ExprNodes.cpp:7636–7663

Generate BLR for a negated zero (take care about possible DECFLOAT).

// Generate BLR for a negated zero (take care about possible DECFLOAT).
void LiteralNode::genNegZero(DsqlCompilerScratch* dsqlScratch, int prec)
{
	char buf[32];		// 18 bytes for max number of digits + some reserve
	char* s = buf;
	*s++ = '-';
	*s++ = '0';

	if (prec)
	{
		*s++ = '.';
		while (prec--)
			*s++ = '0';
	}
	*s = 0;

	dsc desc;
	desc.dsc_dtype = dtype_double;
	desc.dsc_scale = 0;
	desc.dsc_length = sizeof(double);
	desc.dsc_address = (UCHAR*) buf;

	GEN_descriptor(dsqlScratch, &desc, true);

	const USHORT len = static_cast<USHORT>(s - buf);
	dsqlScratch->appendUShort(len);
	if (len)
		dsqlScratch->appendBytes(desc.dsc_address, len);
}

// Generate BLR for a constant.
void LiteralNode::genConstant(DsqlCompilerScratch* dsqlScratch, const dsc* desc, bool negateValue, USHORT numStringLength)