$onehot

If you are creating automatic stimulus using the randomize() method and you need a value to be one-hot, you can use the built in $onehot assertion.  This assertion returns a 1 if the value inside it is a one-hot.  The assertion looks like this:

assert(myreq.randomize() with{
$onehot(onehot_reg) == 1;});


This code will clear all the bits in onehot_reg then randomly set one of them.