Optimize observers #13643
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Optimize observers #13643
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Inline the lookup whether a function is observed at all. This strategy is also used for FRAMELESS calls. If the frameless call is observed, we instead allocate a call frame and push the arguments, to call the the function afterwards. Doing so is still a performance benefit as opposed to executing individual INIT_FCALL+SEND_VAL ops. Thus, even if the frameless call turns out to be observed, the call overhead is slightly lower than before. If the internal function is not observed at all, the unavoidable overhead is fetching the FLF zend_function pointer and the run-time cache needs to be inspected. As part of this work, it turned out to be most viable to put the result operand on the ZEND_OP_DATA instead of ZEND_FRAMELESS_ICALL_3, allowing seamless interoperability with the DO_ICALL opcode. This is a bit unusual in comparison to all other ZEND_OP_DATA usages, but seems to not pose problems overall. Signed-off-by: Bob Weinand <bobwei9@hotmail.com>
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Accidentally pushed to the wrong repository. Re-opened as #13649. |
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Inline the lookup whether a function is observed at all. This strategy is also used for FRAMELESS calls. If the frameless call is observed, we instead allocate a call frame and push the arguments, to call the the function afterwards. Doing so is still a performance benefit as opposed to executing individual INIT_FCALL+SEND_VAL ops. Thus, even if the frameless call turns out to be observed, the call overhead is slightly lower than before. If the internal function is not observed at all, the unavoidable overhead is fetching the FLF zend_function pointer and the run-time cache needs to be inspected.
As part of this work, it turned out to be most viable to put the result operand on the ZEND_OP_DATA instead of ZEND_FRAMELESS_ICALL_3, allowing seamless interoperability with the DO_ICALL opcode. This is a bit unusual in comparison to all other ZEND_OP_DATA usages, but seems to not pose problems overall.
Note: I haven't yet looked at the JIT changes necessary to support observed FRAMELESS_ICALL there. But drafting the PR now to evaluate the general approach aside from JIT.