Rearranging control unit to encorporate stage classes for non-pipelined execution. Will reuse the same methods for fetching, decoding, executing and write back; these will eventually be embedded in the stages.
Deleted unnecessary register references.
Deleted unnecessary register references.
Copied instruction() execute from control unit class; needs a little rearranging to take into account use of write back for arithmetic instructions.
For standard execution.
Abstract WriteBackStage class, containing methods common to standard and pipelined write back stage.
For non pipelined execution.