GH-131498: Allow 'peek' variables to be modified#132506
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markshannon merged 1 commit intoApr 14, 2025
python:mainpython/cpython:mainfrom
faster-cpython:allow-modification-peek-variablesfaster-cpython/cpython:allow-modification-peek-variablesCopy head branch name to clipboard
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GH-131498: Allow 'peek' variables to be modified#132506markshannon merged 1 commit intopython:mainpython/cpython:mainfrom faster-cpython:allow-modification-peek-variablesfaster-cpython/cpython:allow-modification-peek-variablesCopy head branch name to clipboard
markshannon merged 1 commit into
python:mainpython/cpython:mainfrom
faster-cpython:allow-modification-peek-variablesfaster-cpython/cpython:allow-modification-peek-variablesCopy head branch name to clipboard
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iritkatriel
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Apr 14, 2025
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This PR lifts the restriction on the modification of input and "peek" variables.
This restriction was supposed to help avoid reference leaks, but actually just makes it annoying and inefficient to change values on the stack.
Plus, we have a better way to detect leaks on the stack:
Py_STACKREF_DEBUG.Doing this allows us to clean up some code and, more importantly for TOS caching, turn some arrays back into scalars.
This PR modifies
SWAPand_MAKE_CALLARGS_A_TUPLEto demonstrate the simplification.We can make further simplifications, but I'll save those for an other PR for ease of review.