Intelligent cell swapping based on ceiling determination, floor determination, and cell attribute weighting criteria

Embodiments of the inventive concept include a computer-implemented method for intelligently swapping circuit cells and an associated intelligent cell swapper logic section. The technique can include receiving, by an intelligent cell swapper logic section, a synthesized gate level netlist including cells each having an initial cell class. A cell class sorter can sort cell classes in order of leakage. A ceiling finder can swap the initial cell class for each of the cells to a highest cell leakage class, and determine a ceiling frequency. A floor finder can swap the highest cell leakage class for each of the cells to a lowest cell leakage class, and determine a floor frequency. An effective swap weight calculator section can determine an effective swap weight for a subset of cells based on cell attribute weighting criteria. The timing paths can be optimized to meet the ceiling frequency without unnecessarily using high leakage cells.