gh-134889: Fix handling of a few opcodes when optimizing LOAD_FAST
#134958
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`FORMAT_SIMPLE` leaves its operand on the stack if its a unicode object. Since we cannot determine that at analysis (compile) time, treat it conservatively and assume it always leaves the operand on the stack.
It leaves the function on the stack
`GET_YIELD_FROM_ITER` doesn't consume its operand if its a coroutine or generator, so treat it conservatively. `END_SEND` leaves the TOS.
It leaves the TOS in place.
Load special may leave `self` on TOS. Treat it conservatively and assume it always does.
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I suppose this means Python 3.14 is going to see an ABI breakage too, is that correct? |
I don’t think so. This doesn’t change the binary layout of anything. What about this would cause an ABI breakage? |
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It changed |
I think I’m missing something. The magic number changes with every minor release. Since we haven’t released 3.14 yet, bumping the magic number shouldn’t cause any additional pain beyond what’s felt with a normal release. |
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A few Linux distributions have already engaged in a lot of Python 3.14 testing (at least Fedora and Gentoo I'm aware of), and these systems will be affected by the magic number change. |
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In Fedora, we can deal with the chnage of the magic number in b3. But the sooner it happens the better. |
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Thanks @mpage for the PR 🌮🎉.. I'm working now to backport this PR to: 3.14. |
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Sorry, @mpage, I could not cleanly backport this to |
…FAST` (python#134958) We were incorrectly handling a few opcodes that leave their operands on the stack. Treat all of these conservatively; assume that they always leave operands on the stack. (cherry picked from commit 6b77af2)
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GH-135187 is a backport of this pull request to the 3.14 branch. |
We were incorrectly handling a few opcodes that leave their operands on the stack. Treat all of these conservatively; assume that they always leave operands on the stack.
FORMAT_SIMPLEleaves its operand on the stack if its a unicode object.GET_YIELD_FROM_ITERleaves its operand on the stack if its a coroutine or generator object.END_SENDleaves the TOS in place.SET_FUNCTION_ATTRIBUTEleaves the TOS in place.PUSH_EXC_INFOleaves the TOS in place.LOAD_SPECIALmay leave the TOS (self) in place.python: Objects/unicodeobject.c:10387: _PyUnicode_JoinArray: Assertionres_data == PyUnicode_1BYTE_DATA(res) + kind * PyUnicode_GET_LENGTH(res)' failed.` in sqlglot #134889