Division by zero and Out of memory

if(bccomp($coupon->discount_flat_amount,0,5)){[b]
			[/b]$coupon->discount_flat_amount_orig = round($coupon->discount_flat_amount,(int)$currenciesData[$coupon->discount_currency_id_orig]->currency_locale['int_frac_digits']);
			if($srcCurrency->currency_id!=$mainCurrency->currency_id){
				if(bccomp($srcCurrency->currency_percent_fee,0,2)){
					$coupon->discount_flat_amount+=$coupon->discount_flat_amount*floatval($srcCurrency->currency_percent_fee)/100.0;
				}
				$coupon->discount_flat_amount=(floatval($coupon->discount_flat_amount)/floatval($srcCurrency->currency_rate));  // line 1077
			}
			if($dstCurrency->currency_id!=$mainCurrency->currency_id){
				$coupon->discount_flat_amount=floatval($coupon->discount_flat_amount)*floatval($dstCurrency->currency_rate);
				if(bccomp($dstCurrency->currency_percent_fee,0,2)){
					$coupon->discount_flat_amount+=$coupon->discount_flat_amount*floatval($dstCurrency->currency_percent_fee)/100.0;
				}
			}
			$coupon->discount_flat_amount=round($coupon->discount_flat_amount,(int)$currenciesData[$coupon->discount_currency_id]->currency_locale['int_frac_digits']);
		}else{
			$coupon->discount_flat_amount=0;
}

protected function bindData(&$parent, $data)
	{
		// Ensure the input data is an array.
		if (is_object($data))
		{
			$data = get_object_vars($data);
		}
		else
		{
			$data = (array) $data;
		}

		foreach ($data as $k => $v)
		{
			if ((is_array($v) && JArrayHelper::isAssociative($v)) || is_object($v))
			{
				$parent->$k = new stdClass;
				$this->bindData($parent->$k, $v);
			}
			else
			{
				$parent->$k = $v; // line 421
			}
		}
	}

public function store($data, $id, $group = null)
	{
		$locktest = new stdClass;
		$locktest->locked = null;
		$locktest->locklooped = null;

		$locktest = $this->cache->lock($id, $group);

		if ($locktest->locked == false && $locktest->locklooped == true)
		{
			$locktest = $this->cache->lock($id, $group);
		}

		$sucess = $this->cache->store(serialize($data), $id, $group); // line 224

		if ($locktest->locked == true)
		{
			$this->cache->unlock($id, $group);
		}

		return $sucess;
	}