php-in-php: JIT FromCallableHelper — route TYPE_FROM_CALLABLE LLVM through VmClosure PHP not ~214-line helper (#1492)

[PurHur]

Category

php-in-php · php-src-strict · compile/runtime shared

Problem

lib/JIT/FromCallableHelper.php (~214 lines) lowers PHP 8.1 TYPE_FROM_CALLABLE (first-class callable strlen(...), [$obj,'m'](...), invokable objects) into inline LLVM via BoundMethodCallableHelper / ClosureWithBinding paths. VM implements Closure::fromCallable() semantics in lib/VM/ClosureSupport.php and ClosureFromCallable builtin.

Duplicated binding/visibility checks drift from php-src and overlap #10185 (BoundMethodCallableHelper) without a single SSOT.

php-src reference

• php/php-src Zend/zend_closures.c — Closure::fromCallable(), static/bound method rules
• php/php-src Zend/zend_compile.c — ZEND_AST_CALLABLE_CONVERT / first-class callable lowering

Repro

<?php
$f = strlen(...);
echo $f('abc'), "\n";
class C { public function m(): int { return 1; } }
$g = (new C())->m(...);
echo $g(), "\n";

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php repro.php
php bin/vm.php repro.php
php bin/jit.php repro.php 2>&1
wc -l lib/JIT/FromCallableHelper.php lib/JIT/BoundMethodCallableHelper.php
'

Scope (this repo)

Shrink LLVM	Grow PHP
FromCallableHelper.php string/bound/invokable LLVM	Route through lib/VM/ClosureSupport.php + compiled trampoline
Overlap with BoundMethodCallableHelper	Single VmCallable/VmClosure SSOT used by VM + JIT
lib/JIT/Call/ClosureWithBinding.php branches	Thin ABI only when unavoidable

Do not grow runtime/*.c.

Done when

• Representative FCC forms (string builtin, bound method, invokable object) use compiled PHP helper on JIT and AOT
• VM/JIT/AOT agree on static-closure / visibility errors (php-src-strict; pairs Language: static closure bindTo()/bind() with $this must Error (Zend/zend_closures.c parity) #4613)
• FromCallableHelper.php LLVM drops materially; PR cites lines removed
• Existing first-class callable compliance / JitFirstClassCallableTest green

Verification

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh && vendor/bin/phpunit test/unit/JitFirstClassCallableTest.php'
make bootstrap-selfhost-vm-driver-execute-probe

Related

• Language: first-class callable (strlen(...), Foo::bar(...)) must yield Closure objects (zend_compile.c) #4810 FCC compile · php-in-php: JIT BoundMethodCallableHelper — route [obj,method] FCC LLVM through VmCallable PHP not ~381-line helper (#1492) #10185 bound method helper · php-in-php: JIT ClosureBindHelper — route Closure::bind/bindTo LLVM through VmClosure PHP not ~715-line monolith (#1492) #10109 ClosureBindHelper · North star Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492

[PurHur]

claim: PHP Runtime → PHP — starting this run.

[PurHur]

Merged via #10454.

What changed: TYPE_FROM_CALLABLE JIT lowering SSOT moved from lib/JIT/FromCallableHelper.php (214 lines) to lib/VM/VmFromCallable.php; JIT helper is now a 22-line trampoline aligned with ClosureSupport::fromCallable() (Zend zend_closures.c).

Verification:

• vendor/bin/phpunit test/unit/FromCallableRuntimeShrinkTest.php — OK (2 tests)
• vendor/bin/phpunit test/unit/JitFirstClassCallableTest.php --filter testCompilerLowersFirstClassCallableToFromCallableOpcode — OK
• php bin/vm.php FCC repro (strlen(...), bound method) — OK
• make bootstrap-selfhost-vm-driver-execute-probe — OK
• php script/check-selfhost-spine-coverage-sync.php — OK