Nikita Kniazev added the comment: > The purpose of the issue is unclear to me.
I was asked to open an issue by Serhiy Storchaka on the GitHub PR. > Why do you want to replace while with for? For readability? Yes, I have open a PR just to improve the readability, because I was surprised by this incrementing-decrementing statements like you. > You should ask Raymond Hettinger for the rationale. The commit message says > "better generated code (on both GCC and CLang)", but there is no benchmark > nor any data to validate this. The purpose is clear to me - to eliminate postincrement and temporary variable that it requires. > Nowadays, C compilers are very smart and implement crazy optimizations. > Python releases are compiled using PGO, or even PGO+LTO. Please compile your > benchmark using PGO. I expect that compilers emit the same machine code at > the end for "while" and "for" loops. > The question is also if your benchmark is revelant for the _collections > module. > What should I see in your benchmark? I see that results are the same for > while and for_loop except a minor noise in the benchmark. Benchmark was made to show that location of cmp+jmp location (look at asm output for more info) makes no sense to performance. Actually I do not want to spend more time on a such minor change. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue29698> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
