Provide script to TSSA build in tracing JIT #18353
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nielsdos
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For the following script:
```php
final class Foo {
public $prop = 0;
}
function test(Foo $obj) {
$obj->prop=1;
}
$foo = new Foo;
for ($i=0;$i<3;$i++) {
test($foo);
}
```
When comparing the TSSA (via opcache.jit_debug) vs the opcache SSA
(via opcache.opt_debug_level=0x400000) we note that in TSSA, the RECV op
for `test` does not infer the type of the argument to be class `Foo`.
This is because the optimizer uses the `script` pointer to figure out
known classes but TSSA always sets `script` to NULL. This in turn
generates suboptimal assembly because `zend_may_throw` returns 1 due to
the unknown CE in the TSSA, resulting in an extra exception check in the
assembly code.
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For the following script:
When comparing the TSSA (via opcache.jit_debug) vs the opcache SSA (via opcache.opt_debug_level=0x400000) we note that in TSSA, the RECV op for
testdoes not infer the type of the argument to be classFoo. This is because the optimizer uses thescriptpointer to figure out known classes but TSSA always setsscriptto NULL. This in turn generates suboptimal assembly becausezend_may_throwreturns 1 due to the unknown CE in the TSSA, resulting in an extra exception check in the assembly code.