[Python-Dev] lnotab and the AST optimizer (original) (raw)

Thomas Lee tom at vector-seven.com
Thu Jul 24 17:59:54 CEST 2008

Antoine Pitrou wrote:

Antoine Pitrou <solipsis pitrou.net> writes:

In http://bugs.python.org/issue2459 ("speedup for / while / if with better bytecode") I had the same problem and decided to change the lnotab format so that line number increments are signed bytes rather than unsigned.

By the way, the same change could be done for relative jump offsets in the bytecode (change them from unsigned shorts to signed shorts). Taken together, both modifications would release a lot of constraints on the ordering of code blocks.

Python-Dev mailing list Python-Dev at python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/tom%40vector-seven.com By the way, you were right about JUMP_IF_TRUE/JUMP_IF_FALSE. It's far too late. Apologies.

I'm still pretty sure this is the peepholer's doing, though, and if that's the case then I want to try and deal with it at the AST level.

Which is what's being achieved with the AST optimization I originally proposed, right?

Cheers, T

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