Reconfigurable logic, that is digital circuits with run-time programmable interconnect and logic operations, are now appearing as blocks in commercial system-on-a-chip (SoC) ICs. Available both for integration on custom SoCs and as user programmable blocks in off-the-shelf products, reconfigurable logic is used in a wide a variety of roles which mirror its use in the board-level systems which SoCs replace. These roles include glue logic, I/O protocol machines, and high-speed computation.