JIT optimizer: !sym_is_null(obj) is not same as sym_is_not_null(obj) #148078
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JIT optimizer:
URL: http://github.com/python/cpython/issues/148078
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Bug report
Bug description:
The problem with the above pattern is that
objhas three states in terms of nullness, NULL/not-NULL/UKNOWN, so !not-null = UKNOWN/NULL which is not what the optimization is usually expecting (the unknown part).CPython versions tested on:
CPython main branch
Operating systems tested on:
No response
Linked PRs