GH-131498: Replace single-element arrays with scalars in `bytecodes.c` #132615

brandtbucher · 2025-04-16T20:47:58Z

Also, mark some unused items as unused (and fix a bug in the cases generator that sometimes disallowed multiple unused names to occur in the same instruction).

Issue: Top-of-stack caching in the interpreter #131498

markshannon

Nice cleanup, thanks.

bedevere-bot · 2025-04-18T14:20:15Z

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Android 3.x (tier-3) has failed when building commit 40ae889.

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remote: Enumerating objects: 27, done.        
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remote: Counting objects: 100% (27/27), done.        
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remote: Total 14 (delta 13), reused 4 (delta 4), pack-reused 0 (from 0)        
From https://github.com/python/cpython
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Note: switching to '40ae88988c61638ee8625e5c0ee73606ede307bb'.

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Turn off this advice by setting config variable advice.detachedHead to false

HEAD is now at 40ae88988c6 GH-131498: Replace single-element arrays with scalars in bytecodes.c (GH-132615)
Switched to and reset branch 'main'

configure: WARNING: no system libmpdecimal found; falling back to bundled libmpdecimal (deprecated and scheduled for removal in Python 3.15)
configure: WARNING: pkg-config is missing. Some dependencies may not be detected correctly.

In file included from ../../Python/ceval.c:1061:
../../Python/generated_cases.c.h:12125:13: warning: code will never be executed [-Wunreachable-code]
 12125 |             stack_pointer -= 3;
       |             ^~~~~~~~~~~~~
../../Python/generated_cases.c.h:12118:13: warning: code will never be executed [-Wunreachable-code]
 12118 |             stack_pointer -= 4;
       |             ^~~~~~~~~~~~~
../../Python/generated_cases.c.h:7435:13: warning: code will never be executed [-Wunreachable-code]
 7435 |             stack_pointer += -1;
      |             ^~~~~~~~~~~~~
3 warnings generated.

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../../configure: line 4059: pkg-config: command not found
configure: WARNING: no system libmpdecimal found; falling back to bundled libmpdecimal (deprecated and scheduled for removal in Python 3.15)
configure: WARNING: pkg-config is missing. Some dependencies may not be detected correctly.

In file included from ../../Python/ceval.c:1061:
../../Python/generated_cases.c.h:12125:13: warning: code will never be executed [-Wunreachable-code]
 12125 |             stack_pointer -= 3;
       |             ^~~~~~~~~~~~~
../../Python/generated_cases.c.h:12118:13: warning: code will never be executed [-Wunreachable-code]
 12118 |             stack_pointer -= 4;
       |             ^~~~~~~~~~~~~
../../Python/generated_cases.c.h:7435:13: warning: code will never be executed [-Wunreachable-code]
 7435 |             stack_pointer += -1;
      |             ^~~~~~~~~~~~~
../../Python/fileutils.c:460:1: warning: unused function 'decode_current_locale' [-Wunused-function]
  460 | decode_current_locale(const char* arg, wchar_t **wstr, size_t *wlen,
      | ^~~~~~~~~~~~~~~~~~~~~
../../Python/fileutils.c:679:1: warning: unused function 'encode_current_locale' [-Wunused-function]
  679 | encode_current_locale(const wchar_t *text, char **str,
      | ^~~~~~~~~~~~~~~~~~~~~
2 warnings generated.
3 warnings generated.
../../Modules/_localemodule.c:148:1: warning: unused function 'is_all_ascii' [-Wunused-function]
  148 | is_all_ascii(const char *str)
      | ^~~~~~~~~~~~
1 warning generated.
../../Modules/_hacl/Lib_Memzero0.c:52:6: warning: "Your platform does not support any safe implementation of memzero -- consider a pull request!" [-W#warnings]
   52 |     #warning "Your platform does not support any safe implementation of memzero -- consider a pull request!"
      |      ^
../../Modules/_hacl/Lib_Memzero0.c:40:10: warning: unused variable 'len_' [-Wunused-variable]
   40 |   size_t len_ = (size_t) len;
      |          ^~~~
2 warnings generated.

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curl: (56) Recv failure: Connection reset by peer

Replace uses of array[1]s with scalars in bytecode definitions

76e5f9a

brandtbucher added skip news interpreter-core (Objects, Python, Grammar, and Parser dirs) labels Apr 16, 2025

brandtbucher self-assigned this Apr 16, 2025

brandtbucher requested review from markshannon and Fidget-Spinner as code owners April 16, 2025 20:47

bedevere-app bot added the awaiting core review label Apr 16, 2025

bedevere-app bot mentioned this pull request Apr 16, 2025

Top-of-stack caching in the interpreter #131498

Open

brandtbucher changed the title ~~GH-131498: Replace uses of array[1]s with scalars in bytecode definitions~~ GH-131498: Replace uses of single-element arrays with scalars in bytecodes.c Apr 16, 2025

brandtbucher changed the title ~~GH-131498: Replace uses of single-element arrays with scalars in bytecodes.c~~ GH-131498: Replace single-element arrays with scalars in bytecodes.c Apr 16, 2025

markshannon approved these changes Apr 18, 2025

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bedevere-app bot added awaiting merge and removed awaiting core review labels Apr 18, 2025

brandtbucher merged commit 40ae889 into python:main Apr 18, 2025
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bedevere-app bot removed the awaiting merge label Apr 18, 2025

tomasr8 mentioned this pull request Apr 19, 2025

gh-131798: JIT: Split CALL_TYPE_1 into several uops #132419

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GH-131498: Replace single-element arrays with scalars in `bytecodes.c` #132615

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⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

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GH-131498: Replace single-element arrays with scalars in `bytecodes.c` #132615

GH-131498: Replace single-element arrays with scalars in `bytecodes.c` #132615