ZipCPU recently posted about working around some poor synthesis results for a kind of mux that I’m going to refer to as a one-hot mux. A one-hot mux is where the control signal that selects which of the mux inputs to output is a one-hot vector of width equal to the number of mux ports. This is opposed to a normal mux where the control signal is a binary index selecting one of the ports, which I’m going to call an indexed mux for the rest of this post.