Well... it parses, and after parsing each group of tokens runs a function. And yes, it replaces some bytecodes, but its lack of an AST means it can only post-process the bytecode.
And everyone I've spoken to refers to it as single-pass.
Post processing the bytecode is what makes it multi-pass. "One-pass" means that it literally makes one pass over the code. Whether it uses an AST or not isn't really relevant.
