You could use regular laundry detergent in your high efficiency washing machine but it won't work as good as the special made laundry detergent that is made for high efficiency washing machines.
The regular laundry detergent won't get your clothes clean enough since it will create too many suds and not get rinsed out of the clothes like it should and it could damage your high efficiency washing machine.
So if you want to get your clothes clean use the detergent made for high efficiency washing machines.