New submission from Brandt Bucher <brandtbuc...@gmail.com>:
The generated bytecode for mapping patterns is more complicated than it needs to be: - Matching sub-patterns involves indexing into a tuple of values in order to extract them. We already know the size of this tuple at compile-time, so we can just unpack it onto the stack instead. - COPY_DICT_WITHOUT_KEYS isn't used anywhere else, and can be emulated with existing, smaller instructions (albeit using quite a few of them). - MATCH_KEYS doesn't need to push a boolean indicating match / no match. It already pushes None on no match, so following it with a simple DUP_TOP() + LOAD_CONST(None) + IS_OP(1) should suffice. These are mostly just refactoring opportunities... quick-and-dirty measurements of Lib/test_patma.py show no performance impact for these changes. ---------- assignee: brandtbucher components: Interpreter Core messages: 396533 nosy: brandtbucher priority: normal severity: normal status: open title: Improve the bytecode for mapping patterns versions: Python 3.11 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue44511> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
