New submission from Joe Jevnik: When star unpacking positions into a function we can avoid a copy iff there are no extra arguments coming from the stack. Syntactically this looks like: `f(*args)`
This reduces the overhead of the call by about 25% (~30ns on my machine) based on some light profiling of just * unpacking. I can imagine this having a slight impact on code that uses this feature in a loop. The cost is minimal when we need to make the copy because the int != 0 check is dwarfed by the allocation. I did not notice a significant change between the slow path and the original code. The macro benchmark suite did not show a difference on my machine but this is not much more complex code. ---------- components: Interpreter Core files: call-function-var.patch keywords: patch messages: 263702 nosy: llllllllll priority: normal severity: normal status: open title: Avoid copy in call_function_var when no extra stack args are passed versions: Python 3.6 Added file: http://bugs.python.org/file42512/call-function-var.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue26802> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
