php-in-php: delete StringRename user-script JitRenameKernel defer — always JitVmHelperLink + RenameJitHelper (re-#19215)

[PurHur]

Category

php-in-php · runtime-shrink (#1492, re-#19215 / #19186 unlink)

Problem

#19215 deleted invokeLibc from JitRename.php but left UserScriptAotDeferNestedJit::shouldDefer() → JitRenameKernel libc rename(2) LLVM in lib/JIT/Builtin/StringRename.php for user-script standalone AOT. #19186 / #19339 / #19966 proved the same builtins can always route through JitVmHelperLink::ensureBridge + *JitHelper PHP (nested helper compile clears PHP_COMPILER_AOT_USER_SCRIPT).

php-src reference

• php/php-src ext/standard/filestat.c — php_rename

PHP implementation target

• lib/JIT/Builtin/StringRename.php — always JitVmHelperLink::ensureBridge → RenameJitHelper (drop implementUserScriptKernel / UserScriptAotDeferNestedJit)
• Keep JitRenameKernel / phpc_rename_kernel only as the nested leaf inside RenameJitHelper (no user-script ABI shortcut)
• test/unit/RenameRuntimeShrinkTest.php — assert no UserScriptAotDeferNestedJit in StringRename.php

Repro

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

Done when

• UserScriptAotDeferNestedJit / implementUserScriptKernel removed from StringRename.php
• User-script AOT rename still goes through RenameJitHelper via ensureBridge
• RenameBuiltinTest AOT + shrink tests green
• make bootstrap-selfhost-vm-driver-execute-probe green
• PR body cites lines removed

Refs #1492, #19215, #19186, #19339, #19966

[PurHur]

claim: PHP Runtime → PHP — starting this run.

Pillar 1 (this host):

• php script/bootstrap-inventory.php --check → OK 5360/5360
• make bootstrap-selfhost-link → OK /compiler/build/selfhost
• make bootstrap-selfhost-helloworld → OK (Hello World, emit_path=native)
• ./script/release-readiness.sh --json → still running (shared Docker lock); inventory/link/helloworld green

Plan: delete UserScriptAotDeferNestedJit / implementUserScriptKernel from StringRename.php; always JitVmHelperLink::ensureBridge → RenameJitHelper (Unlink/#19186 shape). Keep JitRenameKernel only as nested leaf for phpc_rename_kernel.

[PurHur]

Approach revision (this run): always-ensureBridge under PHP_COMPILER_AOT_USER_SCRIPT=1 is blocked — RenameJitHelper via helper-runtime returns false / nested compile aborts (munmap_chunk). Same class as red UnlinkBuiltinTest AOT.

Aligning with #19966 / StringFilePutContents instead:

• Remove UserScriptAotDeferNestedJit from StringRename
• Thin standalone AOT (isThinStandaloneAotMain) → JitRenameKernel libc body (rename_libc_entry)
• Embed / non-thin → JitVmHelperLink::ensureBridge → RenameJitHelper

That deletes the NestedJit defer gate without regressing RenameBuiltinTest AOT.

[PurHur]

Merged via #20029

Verification:

• RenameRuntimeShrinkTest OK (no UserScriptAotDeferNestedJit in StringRename)
• RenameBuiltinTest AOT OK (ok/moved/new/nogone)
• bootstrap-selfhost-vm-driver-execute-probe OK

Note: full always-ensureBridge under user-script AOT remains blocked (helper-runtime/RenameJitHelper); this PR matches #19966 thin-libc + drop NestedJit defer gate.