[Tom Anderson]: > What puzzles me, though, are bytecodes 17, 39 and 42 - surely these aren't > reachable? Does the compiler just throw in a default 'return None' > epilogue, with routes there from every code path, even when it's not > needed? If so, why?
Since unreachable code is never executed, there is no performance payoff for optimizing it away. It is not hard to write a dead-code elimination routine, but why bother? It would save a few bytes, slow down compilation time, save nothing at runtime, and make the compiler more complex/fragile. FWIW, the peephole optimizer in Python/compile.c is mature -- the low hanging fruit has already been harvested, leaving the field of remaining optimizations somewhat barren. Raymond -- http://mail.python.org/mailman/listinfo/python-list
