Mark Shannon <m...@hotpy.org> added the comment: On 04/12/17 16:56, Serhiy Storchaka wrote: > > Serhiy Storchaka <storchaka+cpyt...@gmail.com> added the comment: > > Right, this is similar to how the JSR/RET pair was used in for calling the > finally block. > > It seems the main drawback of duplicating of the finally code is not > increasing > the code size (which can be exponential in degenerate cases), but the problem > with determining the boundaries of the finally block.
What exactly is the problem? Why do you need to determine the boundaries of finally blocks? ... > > This is the first step. In the second step I'm going to get rid of dynamic > PyTryBlock and instructions like SETUP_EXCEPT and POP_BLOCK. I think all > necessary information can be determined at compile time and saved in an > auxiliary structure, similarly as line numbers are saved in the packed > co_lnotab array instead of be set by SET_LINENO instructions. Boundaries of > finally block could be stored in the same structure. This will make > try/except/ > finally virtually zero-overhead. Fine, but it isn't necessary for this issue. The overhead of try/except is already quite low. > > Currently there is other problem with Antoine's PR (I didn't know about them > when made a review). There is a gap between calling the __enter__ method and > the SETUP_FINALLY instruction. That wasn't a problem with the original patch. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue17611> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
