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rocky / python-uncompyle6

A cross-version Python bytecode decompiler
GNU General Public License v3.0
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Turn "continue" into "pass" based on line number information #114

Open rocky opened 7 years ago

rocky commented 7 years ago

In Python 3 with jump optimization, uncomplyle6 often adds "continue" statements where it is not needed or where "pass" statements were probably used. https://github.com/rocky/python-uncompyle6/blob/master/test/simple_source/looping/12_if_while_true_pass.py is a good example.

We can probably use line number information to disambiguate. Often these instructions are JUMP_ABSOLUTE. If the offset that these appear at are at a line boundary then probably the source had continue, otherwise pass, when a statement is needed, and nothing otherwise.

We'll probably have to wait until we have a separate control flow pass for this.

rocky commented 7 years ago

I have now done this in a hacky way in commit 449d74af5116aaaf59065c2600c1a5b017b041be and f8a40c1949dc1071cc27c26e19192cd4ca7a03a0 . We should have a more formal rewrite phase after tree generation and before text generation proper.