In a particular embodiment, a method is disclosed that includes identifying a first block of bits within a result to be written to a destination register by an execution unit. The result includes a plurality of bits having the first block of bits and a second block of bits. The first block of bits has a value of zero. The method further includes providing an encoded bit value representing the first block of bits to a control register and selectively writing the second block of bits, but not the first block of bits, to the destination register. The destination register is sized to receive the first and second blocks of bits.