1. A programmable logic device comprising: a bitstream decompressor adapted to decompress a compressed configuration bitstream comprised of a plurality of codewords into corresponding data words of an uncompressed configuration bitstream, the bitstream decompressor including: a buffer for receiving the compressed configuration bitstream, the buffer including shifting logic configured to shift the bitstream through the buffer such that following a shift of a codeword out of the buffer, a codeword to-be-decoded in the buffer has a known position in the buffer; and a Huffman decoder for decoding the codeword to-be-decoded in the known position in the buffer, wherein the Huffman decoder includes a first multiplexer adapted to select from a set of more-prevalent data words and a second multiplexer adapted to select from a null data word and the output of the first multiplexer.