Re: [Python-Dev] Possible optimization for LOAD_FAST ?
> OK, but is it mandatory? For example, in the above code, I can unroll the > loop because I found that range is the usual built-in, 5 is a low-enough > constant, How do you know xrange is xrange and not something else? Cheers, fijal ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] Possible optimization for LOAD_FAST ?
On Fri, Dec 31, 2010 at 12:00 PM, Maciej Fijalkowski wrote: >> OK, but is it mandatory? For example, in the above code, I can unroll the >> loop because I found that range is the usual built-in, 5 is a low-enough >> constant, > > How do you know xrange is xrange and not something else? > > Cheers, > fijal > Err, misread. How do you know that range is a builtin you're thinking about and not some other object? Cheers, fijal ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] Possible optimization for LOAD_FAST ?
2010/12/31 Maciej Fijalkowski > On Fri, Dec 31, 2010 at 12:00 PM, Maciej Fijalkowski > wrote: > >> OK, but is it mandatory? For example, in the above code, I can unroll > the > >> loop because I found that range is the usual built-in, 5 is a low-enough > >> constant, > > > > How do you know xrange is xrange and not something else? > > > > Cheers, > > fijal > > > > Err, misread. How do you know that range is a builtin you're thinking > about and not some other object? > > Cheers, > fijal > By a special opcode which could do this work. ]:-) Cesare ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] Possible optimization for LOAD_FAST ?
Cesare Di Mauro wrote: > 2010/12/29 "Martin v. Löwis" wrote: >> Am 28.12.2010 18:08, schrieb Lukas Lueg: Also, the load_fast in lne 22 to reference x could be taken out of the >>> loop as x will always point to the same object That's not true; a debugger may change the value of x. Another example. I can totally remove the variable i, just using the stack, so a debugger (or, in general, having the tracing enabled) cannot even find something to change about it. -1 Debugging is challenging enough as it is -- why would you want to make it even more difficult? ~Ethan~ ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] Possible optimization for LOAD_FAST ?
>> Another example. I can totally remove the variable i, just using the >> stack, so a debugger (or, in general, having the tracing enabled) >> cannot even find something to change about it. Ethan> -1 Ethan> Debugging is challenging enough as it is -- why would you want to Ethan> make it even more difficult? I don't know. Maybe he wants his program to run faster. If you use print statements for the bulk of your debugging (many people do), unrolling loops doesn't affect your debugging ability. Skip ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
[Python-Dev] Summary of Python tracker Issues
ACTIVITY SUMMARY (2010-12-24 - 2010-12-31) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue. Do NOT respond to this message. Issues counts and deltas: open2525 (-17) closed 20058 (+49) total 22583 (+32) Open issues with patches: 1063 Issues opened (19) == #10764: sysconfig and alternative implementations http://bugs.python.org/issue10764 reopened by michael.foord #10771: descriptor protocol documentation has two different definition http://bugs.python.org/issue10771 opened by Devin Jeanpierre #10772: Several actions for argparse arguments missing from docs http://bugs.python.org/issue10772 opened by ipatrol #10775: assertRaises as a context manager should accept a 'msg' keywor http://bugs.python.org/issue10775 opened by r.david.murray #10782: Not possible to cross-compile due to poor detection of %lld su http://bugs.python.org/issue10782 opened by bgamari #10784: os.getpriority() and os.setpriority() http://bugs.python.org/issue10784 opened by giampaolo.rodola #10785: parser: store the filename as an unicode object http://bugs.python.org/issue10785 opened by haypo #10786: unittest.TextTextRunner does not respect redirected stderr http://bugs.python.org/issue10786 opened by cooyeah #10787: [random.gammavariate] Add the expression of the distribution i http://bugs.python.org/issue10787 opened by David.Kremer #10788: test_logging failure http://bugs.python.org/issue10788 opened by pitrou #10789: Lock.acquire documentation is misleading http://bugs.python.org/issue10789 opened by Jyrki.Pulliainen #10790: Header.append's charset logic is bogus, 'shift_jis' and "euc_j http://bugs.python.org/issue10790 opened by r.david.murray #10791: Wrapping TextIOWrapper around gzip files http://bugs.python.org/issue10791 opened by dabeaz #10794: Infinite recursion while garbage collecting loops indefinitely http://bugs.python.org/issue10794 opened by Mihai.Rusu #10796: readline completion flaw http://bugs.python.org/issue10796 opened by rheise #10798: test_concurrent_futures fails on FreeBSD http://bugs.python.org/issue10798 opened by loewis #10799: Improve webbrowser.open doc (and, someday, behavior?) http://bugs.python.org/issue10799 opened by terry.reedy #10800: libffi build failure on HP-UX 11/PA http://bugs.python.org/issue10800 opened by bugs-pyt...@vendor.thewrittenword.com #10801: zipfile.ZipFile().extractall() header mismatch for non-ASCII c http://bugs.python.org/issue10801 opened by M..Z. Most recent 15 issues with no replies (15) == #10800: libffi build failure on HP-UX 11/PA http://bugs.python.org/issue10800 #10799: Improve webbrowser.open doc (and, someday, behavior?) http://bugs.python.org/issue10799 #10798: test_concurrent_futures fails on FreeBSD http://bugs.python.org/issue10798 #10796: readline completion flaw http://bugs.python.org/issue10796 #10789: Lock.acquire documentation is misleading http://bugs.python.org/issue10789 #10787: [random.gammavariate] Add the expression of the distribution i http://bugs.python.org/issue10787 #10775: assertRaises as a context manager should accept a 'msg' keywor http://bugs.python.org/issue10775 #10772: Several actions for argparse arguments missing from docs http://bugs.python.org/issue10772 #10761: tarfile.extractall fails to overwrite symlinks http://bugs.python.org/issue10761 #10760: tarfile doesn't handle sysfs well http://bugs.python.org/issue10760 #10752: build_ssl.py is relying on unreliable behaviour of os.popen http://bugs.python.org/issue10752 #10751: WSGIREF - REMOTE_USER and REMOTE-USER collision http://bugs.python.org/issue10751 #10747: Include version info in Windows shortcuts http://bugs.python.org/issue10747 #10746: ctypes c_long & c_bool have incorrect PEP-3118 type codes http://bugs.python.org/issue10746 #10745: setup.py install --user option undocumented http://bugs.python.org/issue10745 Most recent 15 issues waiting for review (15) = #10801: zipfile.ZipFile().extractall() header mismatch for non-ASCII c http://bugs.python.org/issue10801 #10798: test_concurrent_futures fails on FreeBSD http://bugs.python.org/issue10798 #10790: Header.append's charset logic is bogus, 'shift_jis' and "euc_j http://bugs.python.org/issue10790 #10787: [random.gammavariate] Add the expression of the distribution i http://bugs.python.org/issue10787 #10786: unittest.TextTextRunner does not respect redirected stderr http://bugs.python.org/issue10786 #10785: parser: store the filename as an unicode object http://bugs.python.org/issue10785 #10784: os.getpriority() and os.setpriority() http://bugs.python.org/issue10784 #10766: optparse uses %s in gettext calls http://bugs.python.org/issue10766 #10765: Build regression from automation changes on windows http://bugs.python.org/issue10765 #10756: Error in atexit._run_exitfuncs [...]
Re: [Python-Dev] Possible optimization for LOAD_FAST ?
2010/12/31 Ethan Furman > Cesare Di Mauro wrote: > > > > >> 2010/12/29 "Martin v. Löwis" wrote: >> > >> > >> Am 28.12.2010 18:08, schrieb Lukas Lueg: >>> Also, the load_fast in lne 22 to reference x could be taken out of the >>> >>> loop as x will always point to the same object > >> >>> That's not true; a debugger may change the value of x. >>> >> >> Another example. I can totally remove the variable i, just using the >> stack, so a debugger (or, in general, having the tracing enabled) cannot >> even find something to change about it. >> > > -1 > > Debugging is challenging enough as it is -- why would you want to make it > even more difficult? > > ~Ethan~ With a good test suite you can forget debuggers. In more than 6 years of Python programming, I have used it only two times (to debug an ANTLR generated parser). Cesare ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] Possible optimization for LOAD_FAST ?
2010/12/31 > >>> Another example. I can totally remove the variable i, just using the >>> stack, so a debugger (or, in general, having the tracing enabled) > >> cannot even find something to change about it. > Ethan> -1 > >Ethan> Debugging is challenging enough as it is -- why would you want to >Ethan> make it even more difficult? > > > I don't know. Maybe he wants his program to run faster. > > :D "Aggressive" optimizations can be enabled with explicit options, in order to leave normal "debugger-prone" code. > If you use print statements for the bulk of your debugging (many people > do), > unrolling loops doesn't affect your debugging ability. > > Skip It's a common practice. Also IDEs helps a lot, and advanced interactive shells too (such as DreamPie). Cesare ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
