php-in-php: move PregMatchUserScriptLlvm stubs → JitPregMatchKernel in ext/standard (#1492)

[PurHur]

Category

php-in-php · runtime-shrink (#1492, same pattern as #19389 htmlspecialchars / #19373 getenv / #19344 bin2hex)

Problem

lib/JIT/Builtin/PregMatchUserScriptLlvm.php still houses user-script AOT __compiler_preg_* stubs (~134 LOC) when UserScriptAotDeferNestedJit::shouldDefer(). Embed/full JIT already uses PregJitHelper → VmPregNative.

Same #16075 nested-helper constraint as other kernels: deferred paths cannot nested-compile PregJitHelper reliably. Keep the thin stub kernels — but move them out of lib/JIT/Builtin/ into ext/standard/ so the JIT-builtin surface shrinks.

Also restores Pillar 1 trust: master spine is missing ext/sockets/socket_select.php after #19390 (north-star5-fast / release-readiness red).

php-src reference

• php/php-src ext/pcre/php_pcre.c — PHP_FUNCTION(preg_match) / friends

PHP implementation target

• ext/standard/JitPregMatchKernel.php — new: emit stubs moved from PregMatchUserScriptLlvm
• lib/JIT/Builtin/PregMatchRuntime.php — defer → JitPregMatchKernel::implement
• Delete lib/JIT/Builtin/PregMatchUserScriptLlvm.php
• Update test/unit/PregMatchUserScriptLlvmTest.php / shrink tests + spine require list
• Add missing ext/sockets/socket_select.php to spine (trust gate)
• SSOT remains ext/standard/PregJitHelper.php → VmPregNative

Repro

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
vendor/bin/phpunit test/unit/PregMatchUserScriptLlvmTest.php test/unit/PregMatchRuntimeShrinkTest.php
php script/check-selfhost-spine-coverage-sync.php
make bootstrap-selfhost-vm-driver-execute-probe
'

Done when

• PregMatchUserScriptLlvm.php deleted
• User-script/deferred path uses JitPregMatchKernel in ext/standard/
• PregMatch unit shrink tests green
• php script/check-selfhost-spine-coverage-sync.php green (includes socket_select.php)
• make bootstrap-selfhost-vm-driver-execute-probe green
• PR body cites LOC moved out of lib/JIT/Builtin/

Refs #1492, #16075, #16734, #19389, #19373

[PurHur]

claim: PHP Runtime → PHP — starting this run.

Pre-flight gates:

Gate	Result	Symptom
inventory --check	green	OK 5030/5030
release-readiness	red	spine missing ext/sockets/socket_select.php; north-star5-fast fails same
vm-driver-probe	green	ok
#19339	blocked	NestedJit helper init (#16075) — not this run

Implementing #19399 (PregMatchUserScriptLlvm → JitPregMatchKernel) + spine socket_select.php trust fix.

[PurHur]

Merged #19402

Verification:

• vendor/bin/phpunit PregMatchUserScriptLlvmTest + PregMatchRuntimeShrinkTest + PregPrelinkDeferRuntimeTest → OK (3 tests)
• php script/bootstrap-inventory.php --check → OK 5030/5030
• php script/check-selfhost-spine-coverage-sync.php → OK (incl. socket_select.php)
• make bootstrap-selfhost-vm-driver-execute-probe → OK
• make north-star5-verify-fast → OK

Shrink: deleted lib/JIT/Builtin/PregMatchUserScriptLlvm.php; stubs now in ext/standard/JitPregMatchKernel.php. Spine also gained ext/sockets/socket_select.php (trust fix for #19390 drift).