Ember 3 computed property getter setter

With Ember v3.x, did something change with respect to setting a value for computed property ? In my class, I have a CP named "cp1"

Earlier with Ember 2.x, I used to do

this.cp1 = cp1

But with Ember 3.x, the above is not working. Do I need to update the way CP is set with Ember 3.x ?