Problem in registering a custom register allocator

To get an overview, I am trying to clone the basic register allocator of llvm@12.0.1 with a customised name ‘mybasic’. I have edited all the possible files which contains things related to ‘basic’ named register allocator. Also, I have built llvm thoroughly without any error. Now, I am unable to figure out why it is still showing this error. llc: for the --regalloc option: Cannot find option named 'mybasic'!

How can I fix the error? Also, I am not able to find enough resources. I will really be grateful if someone helps me with this.