Fix function JIT JMPNZ smart branch#21596
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When a smart branch and jump live in separate basic blocks, the JIT can't skip the jitting of the jump, as it may be reachable through another predecessor. When the smart branch is executed using zend_jit_handler(), we're manually writing the result of the branch to the given temporary so that the jump will work as expected. That happens in zend_jit_set_cond(). However, this was only correctly handled for JMPZ branches. The current opline was compared to opline following the jump, which would set the var to 1 if equal, i.e. the branch was not taken, meaning var was not zero. For JMPNZ we need to do the opposite. Fixes phpGH-21593
dstogov
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Apr 2, 2026
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This seems right.
I wonder this wasn't caught early.
The whole PHPT test suite doesn't cover this case.
Thanks!
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Merged as 455ae28. |
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When a smart branch and jump live in separate basic blocks, the JIT can't skip the jitting of the jump, as it may be reachable through another predecessor. When the smart branch is executed using zend_jit_handler(), we're manually writing the result of the branch to the given temporary so that the jump will work as expected. That happens in zend_jit_set_cond().
However, this was only correctly handled for JMPZ branches. The current opline was compared to opline following the jump, which would set the var to 1 if equal, i.e. the branch was not taken, meaning var was not zero. For JMPNZ we need to do the opposite.
Adding the "CI: All variations" label to run the function JIT.
Fixes GH-21593