Abstract: A method for designing a system on a target device is disclosed. Extraction is performed on a first version of the system during synthesis in a first compilation resulting in a first netlist. Optimizations are performed on the first version of the system during synthesis in the first compilation resulting in a second netlist. Placement and routing are performed on the first version of the system in the first compilation. Extraction is performed on a second version of the system having a changed portion during synthesis in a second compilation resulting in a third netlist. The first version of the system in the first netlist and the second version of the system in the third netlist are differentiated to identify identical regions, wherein at least one of the performing and differentiating is performed by a processor.

Abstract: A method for designing a system on a target device is disclosed. A first netlist with a first set of functionally invariant boundaries (FIBs) is generated after performing extraction during synthesis of a first version of the system in a first compilation. One or more of the FIBs is invalidated from the first set after performing optimizations during synthesis in the first compilation resulting in a second netlist with a second set of FIBs. A third netlist with a third set of FIBs is generated after performing extraction during synthesis of a second version of the system having a changed portion in a second compilation. Connectivity of matching nodes from the first netlist and the third netlist reaching FIBs is traversed to identify equivalent nodes associated with identical regions. The identical region in the third netlist is replaced with an optimized synthesized region from the second netlist.