How the PLsy courses are split varies a lot. Where I went (Harvey Mudd), compilers was optional and not taken by most students, but there were two required Programming Languages courses, which involved parsing, ASTs, interpreters, tree transformations, and some other things you might otherwise find in a compilers course, but with less of a low-level flavor (no code-gen) and more of a PLs flavor.
The content of such a course also varies by university. I recently came across some university that did offer a compiler course, but it was all theory. Being a geek, I didn't really like that.
