Compiling a circuit design includes receiving the circuit design specified in a hardware description language, detecting, using a processor, a slice of a vector within the circuit design, and determining that the slice is defined by a left slice boundary variable and a right slice boundary variable. A hardware description is generated from the circuit design using the processor by including a first shifter circuit receiving the left slice boundary variable as an input signal, a second shifter circuit receiving the right slice boundary variable as an input signal, a control signal generator coupled to the first and second shifter circuits, and an output stage. The output stage, responsive to a control signal dependent upon an output from the first shifter circuit and an output from second shifter circuit, generates an output signal including newly received values from a data signal only for bit locations of the output signal corresponding to the slice.