Systems and methods are provided for mapping logic functions from logic
elements ("LEs") into synchronous embedded memory blocks ("EMBs") of
programmable logic devices ("PLDs"). This technique increases the amount
of logic that can fit into the PLD. Where area savings are significant,
smaller PLDs may be selected to implement a particular circuit. One
aspect of the invention relates to methods for identifying sequential
cones of logic that may be mapped into synchronous EMBs. After the
sequential logic cones are identified for mapping into a synchronous EMB,
the logic cone may be selected, expanded, restructured, and retimed, as
necessary, to implement the mapping. Another aspect of the invention
relates to techniques for handling architectural restrictions of
synchronous EMBs, such as the inability to implement the asynchronous
behavior of synchronous logic.