TECHNIQUES FOR IDENTIFYING FUNCTIONAL BLOCKS IN A DESIGN THAT MATCH A TEMPLATE AND COMBINING THE FUNCTIONAL BLOCKS INTO FEWER PROGRAMMABLE CIRCUIT ELEMENTS

Techniques are provided that combine functional blocks in a user design into fewer programmable circuit elements. Systems and methods of the present invention can combine functional blocks in a user design into a single programmable circuit element. A plurality of functional blocks in a user design that can be combined are identified. The possible combinations of functional blocks can be sorted according to a gain function. The gain function can, for example, weigh routing delays caused by a combination. The most desirable combination is selected from the sorted list of possible combinations. The selected combination is checked to see if it is feasible in light of electrical and user-specified constraints. If the combination is feasible, the combination is performed. Combinations continue to be performed by selecting the most desirable combinations from the sorted list.