Add runtime type inference verification

[iluuu1994]

TODO:

• Move zend_execute.c/zend_vm_gen.php into separate file
• Re-add COMMUNTIY to push to verify

[dstogov]

Do you see any existing failures now?
Are you going to check JIT and PHP built with DZEND_VERIFY_TYPE_INFERENCE together? ZEND_VERIFY_INFERENCE_DEF and ZEND_VERIFY_INFERENCE_USE are not going to be called with JIT.

[iluuu1994]

Do you see any existing failures now?

No, I didn't see any more failures the last time I checked.

ZEND_VERIFY_INFERENCE_DEF and ZEND_VERIFY_INFERENCE_USE are not going to be called with JIT.

Hmm, I did not think about this. That makes the flag less useful for the COMMUNTIY build. Do you think it would be possible to add some hook to the JIT?

[dstogov]

ZEND_VERIFY_INFERENCE_DEF and ZEND_VERIFY_INFERENCE_USE are not going to be called with JIT.

Hmm, I did not think about this. That makes the flag less useful for the COMMUNTIY build.

Do you mean COMMUNIT tests? We may run them with ZEND_VERIFY_TYPE_INFERENCE without JIT and then with JIT but without ZEND_VERIFY_TYPE_INFERENCE.

Do you think it would be possible to add some hook to the JIT?

No :)
JIT keeps some values in CPU register and doesn't always maintain consistent VM stack on purpose.

[iluuu1994]

@dstogov Right. Running community build twice is certainly an option. It significantly increases nightly runtime which I'm generally trying to avoid. But if verification in JIT is not an option then let's do that.

[dstogov]

@dstogov Right. Running community build twice is certainly an option. It significantly increases nightly runtime which I'm generally trying to avoid. But if verification in JIT is not an option then let's do that.

It may be better to have a single nightly task for PHP master with ZEND_VERIFY_TYPE_INFERENCE that run make test and few community tests. Just not to pollute the other tasks.

[danog]

Btw, my PR at #12406 can help with greatly reducing execution time for nightly tests by parallelizing them :)

[iluuu1994]

I'm not too concerned about execution time (by the time I wake up nightly is usually done), but CI time as a whole (i.e. load on the planet). The community build is very slow partly because it's run with a debug build and ASAN. This isn't necessary for type inference at all, so another strategy might be to use a release build for this.

[danog]

@iluuu1994 you think you could also add my Psalm/phpstan entries for the community tests? (at least to test them temporarily in this PR)

[iluuu1994]

@dstogov I changed this PR to use the VM_TRACE mechanism instead, which I found more reliable than hooking into ZEND_VM_NEXT_OPCODE_EX. This included an additional VM_TRACE_OP_END hook. Please let me know if you're ok with this approach.

[dstogov]

I don't see any serious problems.

It would be great to separate ""debug info"" from zend_op, but this will complicate and slow down the patch.

Another related idea - it's possible to support ZEND_VERIFY_TYPE_INFERENCE only for CALL VM. This should significantly reduce the amount of the debugging code.

Anyway, I think this may be merged as is.

[dstogov]

What is a problem with ccache?

[iluuu1994]

This is just for debugging. All changes from push.yml will be reverted before merging.