A design structure embodied in a machine readable medium used in a design process includes an apparatus for dynamically selecting compiled instructions for execution, the apparatus including an input for receiving static instructions for execution on a first execution unit and receiving dynamic instructions for execution on a second execution unit; and an instruction selection element adapted to evaluate throughput performance of the static instructions and dynamic instructions based on current states of the execution units and select the static instructions or the dynamic instructions for execution at runtime on the first execution unit or the second execution unit, respectively, based on the throughput performance of the instructions.