[issue42899] Is it legal to eliminate tests of a value, when that test has no effect on control flow?
Mark Shannon added the comment: > How do we know `x` is falsey without calling `bool()` on it? We don't, but in `if x: pass`, it doesn't matter. Discounting side-effects in __bool__, the code does nothing regardless of the value of `x`. -- ___ Python tracker <https://bugs.python.org/issue42899> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42634] Incorrect line number in bytecode for try-except-finally
New submission from Mark Shannon : The following code, when traced, produces a spurious line event for line 5: a, b, c = 1, 1, 1 try: a = 3 except: b = 5 finally: c = 7 assert a == 3 and b == 1 and c == 7 Bug reported by Ned Batchelder https://gist.github.com/nedbat/6c5dedde9df8d2de13de8a6a39a5f112 -- assignee: Mark.Shannon messages: 382958 nosy: Mark.Shannon, nedbat priority: release blocker severity: normal stage: needs patch status: open title: Incorrect line number in bytecode for try-except-finally type: behavior versions: Python 3.10 ___ Python tracker <https://bugs.python.org/issue42634> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42615] Redundant jump instructions due to deleted unreachable bytecode blocks
Mark Shannon added the comment: New changeset c71581c7a4192e6ba9a79eccc583aaadab300efa by Om G in branch 'master': bpo-42615: Delete redundant jump instructions that only bypass empty blocks (GH-23733) https://github.com/python/cpython/commit/c71581c7a4192e6ba9a79eccc583aaadab300efa -- nosy: +Mark.Shannon ___ Python tracker <https://bugs.python.org/issue42615> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42246] Implement PEP 626 -- Precise line numbers for debugging
Mark Shannon added the comment: https://github.com/python/cpython/pull/23780 fixes the finally handling. The if-break case was fixed by earlier changes. -- ___ Python tracker <https://bugs.python.org/issue42246> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42990] Improve the C code for calling Python code: _PyEval_EvalCode()
Mark Shannon added the comment: New changeset 0332e569c12d3dc97171546c6dc10e42c27de34b by Mark Shannon in branch 'master': bpo-42990: Further refactoring of PyEval_ functions. (GH-24368) https://github.com/python/cpython/commit/0332e569c12d3dc97171546c6dc10e42c27de34b -- ___ Python tracker <https://bugs.python.org/issue42990> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42990] Improve the C code for calling Python code: _PyEval_EvalCode()
Change by Mark Shannon : -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue42990> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue33387] Simplify bytecodes for try-finally, try-except and with blocks.
Mark Shannon added the comment: New changeset dea5bf9d15999bfcc58095b157c0678d45b00bdd by Irit Katriel in branch 'master': bpo-33387: update documentation for exception handling opcode changes (GH-24334) https://github.com/python/cpython/commit/dea5bf9d15999bfcc58095b157c0678d45b00bdd -- ___ Python tracker <https://bugs.python.org/issue33387> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42979] _zoneinfo: zoneinfomodule_exec() doesn't check for PyDateTime_IMPORT failure
Mark Shannon added the comment: New changeset c9b8e9c421b57acdcaf24fab0c93bc29b3ef7c67 by Victor Stinner in branch 'master': bpo-42979: Enhance abstract.c assertions checking slot result (GH-24352) https://github.com/python/cpython/commit/c9b8e9c421b57acdcaf24fab0c93bc29b3ef7c67 -- nosy: +Mark.Shannon ___ Python tracker <https://bugs.python.org/issue42979> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43054] What does the existence of a struct in a header file imply about the C-API
New submission from Mark Shannon :
Given the lack of explicit documentation on this subject, and differing
opinions among core developers, I though it would be good to discuss how the
existence of a struct in a header file constrains the C-API.
Original PR provoking this discussion:
https://github.com/python/cpython/pull/24298
Suppose a header file, e.g. funcobject.h, contains a struct, e.g.
PyFunctionObject, to what extent is that struct part of the API?
If a struct is present in a header file, there are three options for what means
in terms of the API (that make sense to me).
1. That the struct is not part of the API and may be freely changed or deleted.
2. That the struct is produced, or initialized, by an API function, which
implies that existing fields will continue to exist, but they can be reorder or
added to.
3. That the struct is consumed by an API function, which implies that the
struct must keep its exact shape, only adding fields if flags are present in
the pre-existing fields to indicate the use of the extension.
PyTypeObject is an example of (3).
We should be able to infer which of the above cases applies, if not explicitly
documented, for any struct.
Using PyFunctionObject in funcobject.h as an example:
There is no API function or macro that directly produces or consumes the
struct, which would imply case 1. But, the struct is documented as the struct
for Python functions, and `PyFunction_Check()` exists, which strongly implies
that the following code is OK:
if (PyFunction_Check(obj)) {
PyFunctionObject *func = (PyFunctionObject *)obj;
...
which therefore implies that (2) applies.
(3) does not apply as there is no API that takes a PyFunctionObject struct as a
parameter.
Similar logic can be applied to other parts of the API.
Rather than go through this tortuous analysis for all headers, it might be
better to document which structs are part of the API.
--
messages: 385851
nosy: Mark.Shannon, gvanrossum, petr.viktorin, vstinner
priority: normal
severity: normal
status: open
title: What does the existence of a struct in a header file imply about the
C-API
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[issue42899] Is it legal to eliminate tests of a value, when that test has no effect on control flow?
Mark Shannon added the comment: Option 3 with what semantics exactly? https://docs.python.org/3/reference/datamodel.html#object.__bool__ says that __bool__ should return True or False. If we don't allow the optimizer the freedom to assume that __bool__ is self-consistent and has no side effects, then we need to define what happens for stuff like: class FlipFlop: def __init__(self): self.val = random.choice((True, False)) def __bool__(self): self.val = not self.val return self.val Saying that only the second test can be removed is hard to define in a way that we can reliably implement. For example, it makes the simplification of `x = True and y` to `x = y` problematic. We routinely remove any tests of `if True:` or `while True:`, but the removal of `if True:` and the simplification of `x = True and y` to `x = y` is basically the same thing in the CFG. -- ___ Python tracker <https://bugs.python.org/issue42899> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42899] Is it legal to eliminate tests of a value, when that test has no effect on control flow?
Mark Shannon added the comment:
It isn't a specific optimization at all, but the combination of several.
I will change the behavior to match what appears to be the consensus.
BUT, we need to define what the semantics should be. Otherwise implementing the
compiler is just guesswork.
As for a definition of what is legal, the best I can come up with is:
"Repeated bool() checks of a value in short-circuiting expressions ('and' and
'or') may be eliminated if the result can be deduced using boolean algebra."
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[issue42899] Is it legal to eliminate tests of a value, when that test has no effect on control flow?
Change by Mark Shannon : -- keywords: +patch pull_requests: +23232 stage: -> patch review pull_request: https://github.com/python/cpython/pull/24417 ___ Python tracker <https://bugs.python.org/issue42899> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44338] Port LOAD_GLOBAL to adaptive interpreter
Mark Shannon added the comment: New changeset eecbc7c3900a7f40d8498b151db543a202c72f74 by Mark Shannon in branch 'main': bpo-44338: Port LOAD_GLOBAL to PEP 659 adaptive interpreter (GH-26638) https://github.com/python/cpython/commit/eecbc7c3900a7f40d8498b151db543a202c72f74 -- ___ Python tracker <https://bugs.python.org/issue44338> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
Change by Mark Shannon : -- pull_requests: +25306 pull_request: https://github.com/python/cpython/pull/26718 ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44417] bytecode<>line number mapping and f_lasti seem wrong in 3.10.0b2
Mark Shannon added the comment: What does "seem wrong" mean? What exactly is the problem? -- ___ Python tracker <https://bugs.python.org/issue44417> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44283] Add jump table for certain safe match-case statements
Mark Shannon added the comment: This is going in the wrong direction. Rather than add more complex instructions for use only by pattern matching, we need to simplify the individual operations and re-use existing instructions. That way pattern matching can benefit from the general performance improvements that we are making. If you are serious about improving the performance of pattern matching, you need to do the following in the compiler: 1. Generate a decision tree. 2. Improve that decision tree so that fewer decisions are required. 3. Generate bytecode from that tree that uses lower level operations. E.g. match x: case [1]: A case [2]: B The initial decision tree looks like: if is_sequence(x): if len(x) == 1: if x[0] == 1: A if is_sequence(x): if len(x) == 1: if x[0] == 2: B which can be improved to: if is_sequence(x): if len(x) == 1: if x[0] == 1: A elif x[0] == 2: B For a sequence of integer constants, introducing the test `type(x) == int` at the start would allow you to convert the linear sequence of tests into a tree. Reducing `n` tests to `ln(n) + 1` tests. -- nosy: +Mark.Shannon ___ Python tracker <https://bugs.python.org/issue44283> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38211] clean up type_init()
Mark Shannon added the comment: New changeset ab030d6f9d73e7f6c2213c2e308d1ceb04761485 by Sergey Fedoseev in branch 'main': bpo-38211: Clean up type_init() (GH-16257) https://github.com/python/cpython/commit/ab030d6f9d73e7f6c2213c2e308d1ceb04761485 -- nosy: +Mark.Shannon ___ Python tracker <https://bugs.python.org/issue38211> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
Change by Mark Shannon : -- pull_requests: +25344 pull_request: https://github.com/python/cpython/pull/26759 ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44187] Implement infrastructure for quickening and specializing
Mark Shannon added the comment: New changeset 001eb520b5757294dc455c900d94b7b153de6cdd by Mark Shannon in branch 'main': bpo-44187: Quickening infrastructure (GH-26264) https://github.com/python/cpython/commit/001eb520b5757294dc455c900d94b7b153de6cdd -- ___ Python tracker <https://bugs.python.org/issue44187> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44338] Port LOAD_GLOBAL to adaptive interpreter
New submission from Mark Shannon : Port the implementation of LOAD_GLOBAL to the new adaptive interpreter Once this and https://bugs.python.org/issue44337 are implemented we can remove the old opcache. -- messages: 395272 nosy: Mark.Shannon priority: normal severity: normal status: open title: Port LOAD_GLOBAL to adaptive interpreter ___ Python tracker <https://bugs.python.org/issue44338> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
New submission from Mark Shannon : Port the implementation of LOAD_ATTR to the new adaptive interpreter -- messages: 395271 nosy: Mark.Shannon priority: normal severity: normal status: open title: Port LOAD_ATTR to adaptive interpreter ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Likely false positive for address sanitizer after fork
New submission from Mark Shannon : Running the buildbot for https://github.com/python/cpython/pull/26595 results in failures: https://buildbot.python.org/all/#/builders/581/builds/63 Which claim that the address calculation in `LOAD_ATTR_MODULE` is out of bounds. The tests pass with an added assert to verify that the address in question is in bounds. All failures seem to happen after a fork, which seems to be a longstanding weakness of the address sanitizer. I'd like to merge https://github.com/python/cpython/pull/26595. I'd also like to keep the buildbots working. Dichotomy. -- messages: 395403 nosy: Mark.Shannon, pablogsal priority: normal severity: normal status: open title: Likely false positive for address sanitizer after fork ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44348] test_exceptions.ExceptionTests.test_recursion_in_except_handler stack overflow on Windows debug builds
Change by Mark Shannon : -- nosy: +Mark.Shannon nosy_count: 9.0 -> 10.0 pull_requests: +25208 pull_request: https://github.com/python/cpython/pull/26623 ___ Python tracker <https://bugs.python.org/issue44348> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44206] Add a version number to dict keys.
Change by Mark Shannon : -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue44206> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44187] Implement infrastructure for quickening and specializing
Change by Mark Shannon : -- pull_requests: +25209 pull_request: https://github.com/python/cpython/pull/26624 ___ Python tracker <https://bugs.python.org/issue44187> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Likely false positive for address sanitizer after fork
Mark Shannon added the comment: If I run the following on main ./configure --with-address-sanitizer make clean make -j12 test I get 22 failures. So something is broken. test_lib2to3 does fork; at least it does when I run it under gdb. -- ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Address sanitizer (gcc version) is generating false positives
Mark Shannon added the comment: I still get quite a few failures on the main branch. It seems like ceval.c:1600 upsets the sanitizer, at least for gcc. There isn't anything wrong with that line, but as I plan to change it anyway I guess it doesn't matter: https://github.com/python/cpython/pull/26595 I plan to get the main branch passing the tests with address sanitization (at least on my machine with my gcc :) Running the tests doesn't seem to take that long (at least not compared with refleak tests). Do you think it would be it feasible to run the address sanitizer on all PRs, so that we can keep it passing? -- title: Likely false positive for address sanitizer after fork -> Address sanitizer (gcc version) is generating false positives ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Address sanitizer (gcc version) is generating false positives
Mark Shannon added the comment: This line seems to be responsible for most of the failures: https://github.com/python/cpython/blob/main/Objects/frameobject.c#L985 Which does appear to be a true positive. -- ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44187] Implement infrastructure for quickening and specializing
Mark Shannon added the comment: No, this is done -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue44187> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Address sanitizer (gcc version) is generating false positives
Mark Shannon added the comment: What commit are you running that on? -- ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44348] test_exceptions.ExceptionTests.test_recursion_in_except_handler stack overflow on Windows debug builds
Mark Shannon added the comment: New changeset 54cb63863f19a7c64d9a3a5fd97bdfc0dd7ab374 by Mark Shannon in branch 'main': bpo-44348: Move trace-info to thread-state (GH-26623) https://github.com/python/cpython/commit/54cb63863f19a7c64d9a3a5fd97bdfc0dd7ab374 -- ___ Python tracker <https://bugs.python.org/issue44348> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
Mark Shannon added the comment: New changeset e117c0283705943189e6b1aef668a1f68f3f00a4 by Mark Shannon in branch 'main': bpo-44337: Port LOAD_ATTR to PEP 659 adaptive interpreter (GH-26595) https://github.com/python/cpython/commit/e117c0283705943189e6b1aef668a1f68f3f00a4 -- ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44338] Port LOAD_GLOBAL to adaptive interpreter
Change by Mark Shannon : -- keywords: +patch pull_requests: +25225 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26638 ___ Python tracker <https://bugs.python.org/issue44338> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Address sanitizer (gcc version) is generating false positives
Mark Shannon added the comment: It looks like I've been a bit unfair to the address sanitizer. It does appear to produce incorrect locations sometimes, but that's not really a false positive and the reports are generally useful. -- ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44313] Generate LOAD_ATTR+CALL_FUNCTION instead of LOAD_METHOD+CALL_METHOD for imports
Mark Shannon added the comment: Yes. Simpler is good. I think it will also be better for performance: In general, we don't know what X is in `from Y import X`. It could be a module or anything else. However, if we are accessing an attribute it is quite likely to be a module or class. For `X` defined by `from Y import X`, `X` is likely to be a module, class, function, or some sort of constant like a string, int or Enum. If it is a string, int or function then it is rare to call a method on it, so we can ignore that case. Calling methods on an Enum constant is probably not very common either (I'm guessing here) For a module, `LOAD_ATTR; CALL_FUNCTION` is clearly better than `LOAD_METHOD; CALL_METHOD`. For a class, specializing `LOAD_ATTR` is no more complex than `LOAD_METHOD`, probably simpler. So, for a class `LOAD_ATTR; CALL_FUNCTION` is no worse than `LOAD_METHOD; CALL_METHOD`, and might be better. Overall, it looks like `X.foo()` when `X` is defiend by `from Y import X` is best as `LOAD_ATTR; CALL_FUNCTION` not `LOAD_METHOD; CALL_METHOD`. -- ___ Python tracker <https://bugs.python.org/issue44313> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
Change by Mark Shannon : -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44363] Address sanitizer (gcc version) is generating false positives
Change by Mark Shannon : -- pull_requests: +25226 pull_request: https://github.com/python/cpython/pull/26639 ___ Python tracker <https://bugs.python.org/issue44363> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44032] Function locals and evaluation stack should be stored in a contiguous, per-thread stack
Change by Mark Shannon : -- pull_requests: +25357 pull_request: https://github.com/python/cpython/pull/26771 ___ Python tracker <https://bugs.python.org/issue44032> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44442] Globals (and presumably builtins) are cleared premuturely in FrameObject
Change by Mark Shannon : -- resolution: -> fixed stage: -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue2> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44442] Globals (and presumably builtins) are cleared premuturely in FrameObject
Mark Shannon added the comment: No problem, I've added a simple test. -- stage: patch review -> ___ Python tracker <https://bugs.python.org/issue2> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43693] Logically merge cell and locals array. They are already contiguous in memory
Change by Mark Shannon : -- assignee: Mark.Shannon -> eric.snow ___ Python tracker <https://bugs.python.org/issue43693> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44442] Globals (and presumably builtins) are cleared premuturely in FrameObject
New submission from Mark Shannon : When calling frame.clear(), the globals (and builtins) are cleared. This is not the case in 3.10. We should restore the 3.10 behavior, as there is no reason not to. Victor, you've mentioned this problem. Did you have a specific example I can add as a test? -- assignee: Mark.Shannon messages: 395995 nosy: Mark.Shannon, vstinner priority: normal severity: normal status: open title: Globals (and presumably builtins) are cleared premuturely in FrameObject type: behavior versions: Python 3.11 ___ Python tracker <https://bugs.python.org/issue2> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44442] Globals (and presumably builtins) are cleared premuturely in FrameObject
Change by Mark Shannon : -- keywords: +patch pull_requests: +25355 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26768 ___ Python tracker <https://bugs.python.org/issue2> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44297] Frame with -1 line number
Change by Mark Shannon : -- keywords: +patch pull_requests: +25382 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26801 ___ Python tracker <https://bugs.python.org/issue44297> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44450] Generator expressions trace differently on Windows than on Mac
Mark Shannon added the comment: Ned, is this a regression (does 3.9 do the right thing on Windows) or an inconsistency between Mac and Windows? I suspect this might have something to do with the PREDICT macros. If that the were the case 3.9 should show the same inconsistency between Windows and the Mac. -- assignee: -> Mark.Shannon ___ Python tracker <https://bugs.python.org/issue44450> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44297] Frame with -1 line number
Mark Shannon added the comment: Thanks Anthony, that's a big help. -- ___ Python tracker <https://bugs.python.org/issue44297> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44032] Function locals and evaluation stack should be stored in a contiguous, per-thread stack
Mark Shannon added the comment: New changeset 0982ded179f280176868c1c4eccf77bf70687816 by Mark Shannon in branch 'main': bpo-44032: Move pointer to code object from frame-object to frame specials array. (GH-26771) https://github.com/python/cpython/commit/0982ded179f280176868c1c4eccf77bf70687816 -- ___ Python tracker <https://bugs.python.org/issue44032> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44446] linecache.getline TypeError when formatting tracebacks in stacks containing an async list comprehension
Mark Shannon added the comment: This appears to be a duplicate of https://bugs.python.org/issue44297 -- ___ Python tracker <https://bugs.python.org/issue6> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44297] Frame with -1 line number
Change by Mark Shannon : -- pull_requests: +25402 pull_request: https://github.com/python/cpython/pull/26821 ___ Python tracker <https://bugs.python.org/issue44297> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44450] Generator expressions trace differently on Windows than on Mac
Mark Shannon added the comment: Hmm, I'm a bit puzzled by that. Did you test with 3.10b3 or the latest build from the 3.10 branch with the fix to https://bugs.python.org/issue44297 included? -- ___ Python tracker <https://bugs.python.org/issue44450> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44450] Generator expressions trace differently on Windows than on Mac
Mark Shannon added the comment: I think this is a combination of https://bugs.python.org/issue44297 and the PREDICT macros. I don't have a windows machine to confirm this on, but I suspect that if you rewrite `doit` as: def doit(): o = ((1,2), (3,4)) o = (a for a in o) for tup in o: x = tup[0] y = tup[1] then you should be able to observe a difference between Windows and Mac on 3.9 as well. -- ___ Python tracker <https://bugs.python.org/issue44450> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
Mark Shannon added the comment: New changeset fb68791a26e157ed3cdeb409c8d8b6cddc7535bd by Mark Shannon in branch 'main': bpo-44337: Improve LOAD_ATTR specialization (GH-26759) https://github.com/python/cpython/commit/fb68791a26e157ed3cdeb409c8d8b6cddc7535bd -- ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44297] Frame with -1 line number
Mark Shannon added the comment: New changeset 7674c83d81905d6afe989ca3f93f08b7939b057c by Mark Shannon in branch '3.10': bpo-44297: Fix missing line number in generator expressions (GH-26821) https://github.com/python/cpython/commit/7674c83d81905d6afe989ca3f93f08b7939b057c -- ___ Python tracker <https://bugs.python.org/issue44297> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44446] linecache.getline TypeError when formatting tracebacks in stacks containing an async list comprehension
Mark Shannon added the comment: With the latest 3.10, I get: File "/home/mark/test/test.py", line 13, in next(bar().__await__(), None) File "/home/mark/test/test.py", line 10, in bar return [chunk async for chunk in foo()] File "/home/mark/test/test.py", line 10, in return [chunk async for chunk in foo()] File "/home/mark/test/test.py", line 6, in foo traceback.print_stack() working! Thomas, can you confirm? -- ___ Python tracker <https://bugs.python.org/issue6> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44486] Modules should alway have a dictionary
Mark Shannon added the comment: New changeset c3f52b4d707a78eb342372a2be00f3eb846a05b9 by Mark Shannon in branch 'main': bpo-44486: Make sure that modules always have a dictionary. (GH-26847) https://github.com/python/cpython/commit/c3f52b4d707a78eb342372a2be00f3eb846a05b9 -- ___ Python tracker <https://bugs.python.org/issue44486> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44500] Document changes to code object.
New submission from Mark Shannon : We are making lots of changes to the code object. We should clearly document all the changes in one place and explain the new design well before 3.11 beta. -- assignee: docs@python components: Documentation messages: 396432 nosy: Mark.Shannon, docs@python, eric.snow, gvanrossum priority: normal severity: normal status: open title: Document changes to code object. type: enhancement versions: Python 3.11 ___ Python tracker <https://bugs.python.org/issue44500> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44486] Modules should alway have a dictionary
Change by Mark Shannon : -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue44486> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44297] Frame with -1 line number
Mark Shannon added the comment: Thanks for the reproducer. -- assignee: -> Mark.Shannon ___ Python tracker <https://bugs.python.org/issue44297> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44486] Modules should alway have a dictionary
Change by Mark Shannon : -- keywords: +patch pull_requests: +25428 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26847 ___ Python tracker <https://bugs.python.org/issue44486> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44486] Modules should alway have a dictionary
New submission from Mark Shannon : It is possible to create a module without a dictionary: m = types.ModuleType.__new__(types.ModuleType) But that is the only way to create to a module without a dict; all other means of creating a module, both in Python and in the C API, result in a fully formed module. Existing code expects that modules will always have a dictionary, e.g. https://github.com/python/cpython/blob/3.10/Include/internal/pycore_moduleobject.h#L35 We should change types.ModuleType.__new__ to properly initialize the module. -- assignee: Mark.Shannon messages: 396316 nosy: Mark.Shannon priority: normal severity: normal status: open title: Modules should alway have a dictionary type: behavior ___ Python tracker <https://bugs.python.org/issue44486> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44297] Frame with -1 line number
Mark Shannon added the comment: New changeset 82e5c28af7049c4f5343c808f172cbe2e145f49b by Mark Shannon in branch 'main': bpo-44297: Fix missing line number in generator expressions (GH-26801) https://github.com/python/cpython/commit/82e5c28af7049c4f5343c808f172cbe2e145f49b -- ___ Python tracker <https://bugs.python.org/issue44297> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44337] Port LOAD_ATTR to adaptive interpreter
Change by Mark Shannon : -- keywords: +patch pull_requests: +25178 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26595 ___ Python tracker <https://bugs.python.org/issue44337> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43693] Logically merge cell and locals array. They are already contiguous in memory
Mark Shannon added the comment: Pablo, Is there a bpo issue for the buildbot failures on Windows? The failures I've been seeing are C stack overflows. Long term, I expect to fix it by decoupling the C and Python stacks. In the short term I have a couple of changes that might get it working again -- ___ Python tracker <https://bugs.python.org/issue43693> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43933] Regression in python3.10 with traceback frame having lineno of -1
Mark Shannon added the comment: New changeset 0acdf255a51b836c0b44f3676797620322974af3 by Mark Shannon in branch '3.10': [3.10] bpo-43933: Force RETURN_VALUE bytecodes to have line numbers (GH-26061) https://github.com/python/cpython/commit/0acdf255a51b836c0b44f3676797620322974af3 -- ___ Python tracker <https://bugs.python.org/issue43933> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44088] traced line number can be None
Mark Shannon added the comment: Duplicate of https://bugs.python.org/issue43933 -- resolution: -> duplicate stage: -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue44088> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue40222] "Zero cost" exception handling
Mark Shannon added the comment: I know PyCode_NewWithPosOnlyArgs is declared as "PyAPI_FUNC" but that can't make it part of the ABI unless it has stable behavior. It can't have stable behavior because its inputs are complex, undefined, have altered semantics and are interlinked in complex ways. Passing the same arguments to PyCode_NewWithPosOnlyArgs for both 3.9 and 3.10 will cause one or other version to crash (interpreter crash, not just program crash). We need to stop adding "PyAPI_FUNC" to everything. Adding a PyAPI_FUNC does not magically make for ABI compatibility, there is a lot more to it than that. The only sane ways to construct a code object are to load it from disk, to compile an AST, or to use codeobject.replace(). Any purported ABI compatibility claims are just misleading and a trap. I can revert the API changes and add a new function, but I think that is dangerously misleading. A compilation error is preferable to an interpreter crash. -- ___ Python tracker <https://bugs.python.org/issue40222> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43933] Regression in python3.10 with traceback frame having lineno of -1
Change by Mark Shannon : -- pull_requests: +24694 pull_request: https://github.com/python/cpython/pull/26054 ___ Python tracker <https://bugs.python.org/issue43933> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue40222] "Zero cost" exception handling
Change by Mark Shannon : -- pull_requests: +24699 pull_request: https://github.com/python/cpython/pull/26059 ___ Python tracker <https://bugs.python.org/issue40222> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43933] Regression in python3.10 with traceback frame having lineno of -1
Change by Mark Shannon : -- pull_requests: +24702 pull_request: https://github.com/python/cpython/pull/26061 ___ Python tracker <https://bugs.python.org/issue43933> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43933] Regression in python3.10 with traceback frame having lineno of -1
Change by Mark Shannon : -- Removed message: https://bugs.python.org/msg393388 ___ Python tracker <https://bugs.python.org/issue43933> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43760] The DISPATCH() macro is not as efficient as it could be.
Mark Shannon added the comment: At yappi/_yappi.c:1261 sets an undocumented field on a CPython internal data structure. What did you believe that was supposed to do? use_tracing is not documented anywhere. We could add the field back and ignore it, but I doubt that would help you much. -- ___ Python tracker <https://bugs.python.org/issue43760> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43933] Regression in python3.10 with traceback frame having lineno of -1
Mark Shannon added the comment: If there is no C-API function that supports your needs, feel free to suggest one. -- ___ Python tracker <https://bugs.python.org/issue43933> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43760] The DISPATCH() macro is not as efficient as it could be.
Mark Shannon added the comment: If there is no C-API function that supports your needs, feel free to suggest one. -- ___ Python tracker <https://bugs.python.org/issue43760> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43933] Regression in python3.10 with traceback frame having lineno of -1
Mark Shannon added the comment: Ned, no line numbers should never be None. (Except under very unusual circumstances, like the trace function raising an error) Taking a look at the disassembly of execsitecustomize, there is a return with no line number, which shouldn't happen. -- ___ Python tracker <https://bugs.python.org/issue43933> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue40222] "Zero cost" exception handling
Mark Shannon added the comment: Thanks everyone for the triaging and fixing. -- ___ Python tracker <https://bugs.python.org/issue40222> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43760] The DISPATCH() macro is not as efficient as it could be.
Mark Shannon added the comment: But what does "use it" mean? What does setting `tstate->use_tracing = 1` do? There is no documented behavior, so how do we know what assumptions people are making about what happens when they set some field to 1? As I said, we could keep the field and ignore it, but that seems worse. -- ___ Python tracker <https://bugs.python.org/issue43760> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44056] Incorrect line number for syntax error.
Change by Mark Shannon : -- resolution: -> fixed stage: patch review -> needs patch status: open -> closed ___ Python tracker <https://bugs.python.org/issue44056> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44056] Incorrect line number for syntax error.
Change by Mark Shannon : -- keywords: +patch pull_requests: +24606 stage: needs patch -> patch review pull_request: https://github.com/python/cpython/pull/25939 ___ Python tracker <https://bugs.python.org/issue44056> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44056] Incorrect line number for syntax error.
New submission from Mark Shannon : Consider this function, which has a syntax error on line 4. >>> def f(): ... try: ... 1/0 ... except: ... pass ... except Exception: ... pass 3.9 reports an incorrect line number of 3. 3.10b reports an even more incorrect line number of -1. Although I've marked this as a "Parser" bug, the offending code is in the compiler. For 3.11, this is fixed by https://github.com/python/cpython/pull/25729 -- assignee: Mark.Shannon components: Parser messages: 393083 nosy: Mark.Shannon, lys.nikolaou, pablogsal priority: release blocker severity: normal stage: needs patch status: open title: Incorrect line number for syntax error. type: behavior versions: Python 3.10 ___ Python tracker <https://bugs.python.org/issue44056> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue39394] re: DeprecationWarning for `flag not at the start of expression` is cutoff too early
Mark Shannon added the comment: I have to admit that I find the truncated version more readable. Some sort of truncation is useful, as a regex could be thousands of character long. Adding the offset to the warning message seems like a useful addition. -- nosy: +Mark.Shannon ___ Python tracker <https://bugs.python.org/issue39394> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue40222] "Zero cost" exception handling
Mark Shannon added the comment: It is very little effort to add back the old function, so that isn't the problem. It won't work properly, but it never did anyway. So I guess that's sort of compatible. Maybe the best thing is to put a big red warning in the docs and hope that warns away people from using it? -- ___ Python tracker <https://bugs.python.org/issue40222> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44032] Function locals and evaluation stack should be stored in a contiguous, per-thread stack
Change by Mark Shannon : -- keywords: +patch pull_requests: +24716 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26076 ___ Python tracker <https://bugs.python.org/issue44032> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44187] Implement infrastructure for quickening and specializing
Change by Mark Shannon : -- keywords: +patch pull_requests: +24868 stage: -> patch review pull_request: https://github.com/python/cpython/pull/26264 ___ Python tracker <https://bugs.python.org/issue44187> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44187] Implement infrastructure for quickening and specializing
New submission from Mark Shannon : As described in PEP 659 (Specializing Adaptive Interpreter) the first part of implementing specialization is to implement the machinery to do the quickening. Conceptually, this is fairly simple: add a new field to the code object, which points to the first instruction in the bytecode. When quickening, we create a new array, copy the old bytecode into it, and make the new field point to it. Without any specialization or superinstructions, this will just waste memory. However, it will pay off soon enough as we implement superinstructions, remove the old "opcache" and add new specializations. We expect to see worthwhile speed ups with just superinstructions, and large speedups when all the above features have been implemented. -- assignee: Mark.Shannon messages: 394013 nosy: Mark.Shannon priority: normal severity: normal status: open title: Implement infrastructure for quickening and specializing type: performance ___ Python tracker <https://bugs.python.org/issue44187> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue40222] "Zero cost" exception handling
Change by Mark Shannon : -- pull_requests: +24671 pull_request: https://github.com/python/cpython/pull/26021 ___ Python tracker <https://bugs.python.org/issue40222> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44240] Incorrect behavior of LOAD_ATTR due to overflow in tp_version
Mark Shannon added the comment: It is extremely unlikely, I agree. But not impossible. I plan to fix it for 3.11. Once I've done that we can decide if backports are worth it. -- ___ Python tracker <https://bugs.python.org/issue44240> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue43693] Logically merge cell and locals array. They are already contiguous in memory
Mark Shannon added the comment: New changeset 6cc800d3634fdd002b986c3ffe6a3d5540f311a0 by Eric Snow in branch 'main': bpo-43693: Clean up the PyCodeObject fields. (GH-26364) https://github.com/python/cpython/commit/6cc800d3634fdd002b986c3ffe6a3d5540f311a0 -- ___ Python tracker <https://bugs.python.org/issue43693> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44240] Incorrect behavior of LOAD_ATTR due to overflow in tp_version
New submission from Mark Shannon : Should the tp_version overflow, and wrap around to a value previously used in the opcache for LOAD_ATTR, then LOAD_ATTR could produce the wrong value. It will take a fair bit of contrivance and a long time to do this, but it is possible: Run some code ~2000 times to get the version cached. Change an attibute of the type about 4 billion times. Rerun the original code. Invalidating all the opcaches is going to be a huge pain, so I propose not allowing the version to overflow but partitioning the 32 bit space something like this: Top 20 bits: Unique per-class ID, 0 and 0xF are reserved. Low 12 bits: Per-class version. tp_version == 0 that no version has been assigned to this class, as yet. (tp_version & 0xFFF) == 0 means that the version tag is temporarily invalid tp_version == 0x means that the version tag is permanently invalid If (tp_version & 0xFFF) != 0 and tp_version != 0x, then the combined 32 bits represents a unique tag of the class's state as it does now. Should the low bits of a class hit 0xFFF then all 32 bits are set to 0x, and we can't cache its version any more. If a class has been changed a 1000 times, then there is unlikely to be much value in caching it anyway. -- components: Interpreter Core messages: 394442 nosy: Mark.Shannon, pablogsal priority: normal severity: normal stage: needs patch status: open title: Incorrect behavior of LOAD_ATTR due to overflow in tp_version type: behavior versions: Python 3.10, Python 3.9 ___ Python tracker <https://bugs.python.org/issue44240> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44206] Add a version number to dict keys.
Mark Shannon added the comment: Which optimizations? LOAD_GLOBAL: Using a keys version instead of a whole dict version means that LOAD_GLOBAL won't leak references. It also means that we can (in the future) remove the PEP 509 version and save 8 bytes per dict. LOAD_ATTR: _PyDict_GetItemHint() still has to do quite a lot of work compared to a version check. The hint approach can't quickly tell us whether a name is not in a dictionary, which is needed for optimizing non-descriptor class attributes. LOAD_METHOD: Because functions are non-overriding descriptors we need to quickly check that the instance does not have an attribute shadowing the method. Why is 32 bits enough? Because the version is reset to zero, whenever the dict keys changes, and only set to non-zero when we explicitly ask for it when optimizing. 4 billion optimization events is a lot. It can't overflow, it just becomes useless when we reach UINT_MAX. Using 64 bits would just waste memory. Overall, versioning the dictionary's keys is more useful and more compact than versioning the dictionary as a whole. -- ___ Python tracker <https://bugs.python.org/issue44206> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44206] Add a version number to dict keys.
New submission from Mark Shannon : Add a version number to dict keys. PEP 509 added a version number to dicts. Unfortunately this is no use for optimizing attribute loads and store on instances. We need to know whether the keys are as expected, not the dict as that is likely to be different each time. We can add a 32 bit version number and actually reduce memory use by taking advantage of the redundancy in the rest of the keys object. -- assignee: Mark.Shannon messages: 394120 nosy: Mark.Shannon, methane, vstinner priority: normal severity: normal stage: needs patch status: open title: Add a version number to dict keys. type: performance ___ Python tracker <https://bugs.python.org/issue44206> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44032] Function locals and evaluation stack should be stored in a contiguous, per-thread stack
Mark Shannon added the comment: What's the test case, exactly? ref.py for the other issue doesn't crash if I change "func.py" to "ref.py" otherwise it just complains that "func.py" doesn't exist. -- ___ Python tracker <https://bugs.python.org/issue44032> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44207] Add a version number to Python functions
New submission from Mark Shannon : In order to specialize calls to Python functions, or to inline them, we need to know that the code object has not changed. It is also useful to know that the globals, builtins and various defaults haven't changed either. Rather than attempting to check these individually it is much simpler and faster to check a version number. -- assignee: Mark.Shannon messages: 394124 nosy: Mark.Shannon priority: normal severity: normal status: open title: Add a version number to Python functions type: performance ___ Python tracker <https://bugs.python.org/issue44207> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44032] Function locals and evaluation stack should be stored in a contiguous, per-thread stack
Change by Mark Shannon : -- pull_requests: +24891 pull_request: https://github.com/python/cpython/pull/26285 ___ Python tracker <https://bugs.python.org/issue44032> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44206] Add a version number to dict keys.
Mark Shannon added the comment: New changeset f8a95df84bcedebc0aa7132b3d1a4e8f000914bc by Mark Shannon in branch 'main': bpo-44206: Add a version number to dictionary keys (GH-26333) https://github.com/python/cpython/commit/f8a95df84bcedebc0aa7132b3d1a4e8f000914bc -- ___ Python tracker <https://bugs.python.org/issue44206> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue42349] Compiler front-end produces a broken CFG
Mark Shannon added the comment: Basic blocks have only a single exit, at the end. https://en.wikipedia.org/wiki/Basic_block If the devguide says otherwise it is wrong. -- ___ Python tracker <https://bugs.python.org/issue42349> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44298] 3.10.0b2 traces with-exit before the break that caused the exit
Mark Shannon added the comment: For context, this behavior was introduced in https://bugs.python.org/issue43933 -- ___ Python tracker <https://bugs.python.org/issue44298> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44298] 3.10.0b2 traces with-exit before the break that caused the exit
Change by Mark Shannon : -- keywords: +patch pull_requests: +25109 stage: needs patch -> patch review pull_request: https://github.com/python/cpython/pull/26513 ___ Python tracker <https://bugs.python.org/issue44298> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44298] 3.10.0b2 traces with-exit before the break that caused the exit
Mark Shannon added the comment: New changeset 937cebc93b4922583218e0cbf0a9a14705a595b2 by Mark Shannon in branch 'main': bpo-44298: Fix line numbers for early exits in with statements. (GH-26513) https://github.com/python/cpython/commit/937cebc93b4922583218e0cbf0a9a14705a595b2 -- ___ Python tracker <https://bugs.python.org/issue44298> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44298] 3.10.0b2 traces with-exit before the break that caused the exit
Mark Shannon added the comment: Why this occurs: with cm: A break translates to something like: ex = cm.__exit__; cm.__enter__() # with cm A ex(...) goto loop_end # break So, the break is traced after the exit call. However, this doesn't seem consistent with try-finally statements which trace any break/continue/return before the finally block. -- keywords: +3.10regression nosy: +pablogsal priority: normal -> release blocker stage: -> needs patch ___ Python tracker <https://bugs.python.org/issue44298> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44298] 3.10.0b2 traces with-exit before the break that caused the exit
Change by Mark Shannon : -- pull_requests: +25111 pull_request: https://github.com/python/cpython/pull/26516 ___ Python tracker <https://bugs.python.org/issue44298> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
