In reply to Raja Rathinam:
Thank you Raja for your reply, I believe the constraint solver will take care of the failure condition you are mentioning (might cause failure if i < Instruction_h[i].Interleaving)
The value of Interleaving will be set in such a range that it will find an object instance of the class Instruction. I have tried the code and working on EDA playground.
Instruction_h[i].Rs0==Instruction_h[i-(Instruction_h[i].Interleaving)].Rd;
Thanks and Regards,
Neal