1. A method for implementing an HDL-specified priority encoder in a programmable IC, comprising the steps of: detecting a priority determination statement including a plurality of tests; implementing a first test in the statement using a first carry multiplexer having a carry input terminal and a carry output terminal, the first test being the test having the highest priority of the plurality of tests; implementing the next highest priority test in the statement using an additional carry multiplexer having a carry input terminal and a carry output terminal, the carry output terminal of the additional carry multiplexer being coupled to the carry input terminal of the carry multiplexer used in the previous step; and repeating the step of implementing the next highest priority test until each test in the statement has been implemented.