Apparatus and methods to track a register value. A microprocessor can include
a first register, a control circuit, and an adder. The first register can store
a tracked register value. The control circuit can include an instruction input
to receive at least a portion of an instruction and a first output to output an
arithmetic operation indication. The adder can include a control input to receive
the arithmetic operation indication, a first input to receive an immediate operand
of an instruction, and a second input to receive the tracked register value.