php-in-php: JIT ReflectionBuiltinHelper — route reflection builtin LLVM through VmReflection PHP not ~336-line monolith (#1492)

[PurHur]

Category

php-in-php · JIT lowering migration

Problem

lib/JIT/ReflectionBuiltinHelper.php (~336 lines) duplicates compile-time class literal checks and runtime reflection plumbing in LLVM:

• class_exists / interface_exists literal fast paths
• ReflectionClass/ReflectionMethod/ReflectionProperty construction guards (Stdlib: class_exists() — VM + LLVM JIT/AOT #1214–Stdlib: is_subclass_of() — VM + LLVM JIT/AOT #1219)
• Lazy ghost / enum / readonly metadata branches

VM path: ext/standard/VmReflection.php already implements reflection in PHP. JIT LLVM re-implements subsets → drift vs VM (readonly #5221, asymmetric #5060, enum cases #9537).

php-src reference

• php/php-src ext/reflection/php_reflection.c — reflection object construction
• php/php-src Zend/zend_compile.c — class table metadata consumed by reflection

Repro (JIT vs VM drift)

Save as test/repro/maintainer_reflection_class_is_readonly.php (from #5221):

<?php
readonly class R {}
$rr = new ReflectionClass(R::class);
echo method_exists($rr, 'isReadOnly') ? 'method:yes' : 'method:no', "\n";

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php bin/vm.php test/repro/maintainer_reflection_class_is_readonly.php 2>&1 | head -4
php bin/jit.php test/repro/maintainer_reflection_class_is_readonly.php 2>&1 | head -4
'

After migration, JIT must call same VmReflection entrypoints — fixing #5221 once applies to both.

Scope (PHP-in-PHP)

Layer	Path
VM SSOT	ext/standard/VmReflection.php — keep expanding real semantics
JIT	lib/JIT/ReflectionBuiltinHelper.php → thin calls into JitReflection* wrappers over VM
Builtin	lib/JIT/ReflectionBuiltinHelper.php delete inline LLVM after parity
Tests	Existing reflection compliance PHPTs must pass JIT

No new C runtime logic.

Done when

• ReflectionBuiltinHelper reduced to trampoline / declare-only LLVM
• JIT + VM output identical on Stdlib: ReflectionClass::isReadOnly() — missing on readonly classes (ext/reflection/php_reflection.c) #5221 / Stdlib: ReflectionProperty — attributes + type + visibility parity (ext/reflection/php_reflection.c) #4384 repro set
• ./script/ci-fast.sh --filter ReflectionBuiltin green
• PR body lists LLVM lines removed

Related

#5221 · #4384 · #5060 · #1492

[PurHur]

claim: PHP Runtime → PHP — batch (issues #9486, #10222)

[PurHur]

claim: PHP Runtime → PHP — batch (issues #11470, #10222)

[PurHur]

Merged via #11477.

LLVM shrink: ReflectionBuiltinHelper classNameFromId select loop → GetClassJitHelper PHP + __phpc_class_name_from_id bridge (336→332 lines in helper).

Verification: shrink tests green; get_class VM+JIT smoke; spine sync + ci-fast green.

Follow-up: method_exists/is_a literal LLVM paths, ReflectionClass::isReadOnly (#5221).