php-in-php: session_encode()/session_decode() JIT/AOT lowering (phase 2 of #6086)

[PurHur]

Category

php-in-php | stdlib | bootstrap

Problem

#6086 landed VM session_encode() / session_decode() via VmSessionSerializer.php, but JIT/AOT call() still throws LogicException('session_encode() not implemented for JIT'). docs/capabilities.md and docs/stdlib-jit-audit.md list both as JIT=no.

Web/session middleware compiled with bin/jit.php cannot snapshot or restore $_SESSION blobs.

php-src reference

• php/php-src ext/session/session.c — PHP_FUNCTION(session_encode), PHP_FUNCTION(session_decode)
• php/php-src ext/session/mod_php.c — php serialize handler wire format (key|serialized)

Repro

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php bin/jit.php -r "session_start(); \$_SESSION[\"k\"]=\"v\"; echo session_encode();"
'

Expect: k|s:1:"v"; — today: LogicException

Scope

Layer	Path
JIT LLVM	lib/JIT/Builtin/SessionEncodeRuntime.php — phpc_session_encode_wire / phpc_session_decode_wire
Ext	ext/standard/JitSessionEncode.php, JitSessionDecode.php; wire session_encode.php / session_decode.php call()
Tests	test/compliance/cases/stdlib/session_encode_decode_jit.phpt
Matrix	script/capability-matrix.php

Done when

• JIT repro prints wire blob without LogicException
• Round-trip compliance PHPT green on JIT
• ./script/ci-fast.sh --filter session_encode green
• No new runtime/*.c — LLVM only in lib/JIT/

[PurHur]

claim: PHP Runtime → PHP — starting this run (session_encode/session_decode JIT lowering, #6086 phase 2).

[PurHur]

Merged via #8253.

Verification:

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
vendor/bin/phpunit --filter session_encode_decode
php bin/jit.php -r "session_start(); \$_SESSION[\"k\"]=\"v\"; echo session_encode();"
'

→ OK (4 tests, 4 assertions); JIT repro prints k|s:1:"v";

No new C runtime — wire encode/decode in lib/JIT/Builtin/SessionEncodeRuntime.php.