cloning a register

Hello,

I am running a simulation on a DUT that has a register model.

what i wish to do is hold a copy of that register model so that at certain times during the simulation

i can compare a current value of a register to a former value of that register taken at a previous point in time.

i don't want to save only the data of the registers, but an array of registers that will hold a copy of the whole register object,

including all of it's fields and other attributes.

i tried to create an array of type uvm_reg                                             uvm_reg registers_copy[]

and then use clone to copy a register to that array                               $cast(registers_copy[i], registers[i].clone());

but i get an error:

UVM_FATAL /tools/snps/vcs/current/etc/uvm-1.1/reg/uvm_reg.svh(3102) @ 3520.6ns: reporter [RegModel] RegModel registers cannot be cloned

how can i create a copy of my register model at certain points in time?

Thanks for your help,

Assaf