Fix AOT examples smoke LLVM verify regressions (#11206)

[PurHur]

Summary

Closes #11206 (partial — parentless standalone-main IR fixed; merge-block blocker remains).

• Root cause: #10854 routed http_response_code through HttpResponseRuntime php-in-PHP JIT; emitResetForStandaloneMain() re-entered implement() during C main wrapper emit, clearing the LLVM insert block → parentless globals (__phpc_session_module_storage, __phpc_progress_note, …).
• Fix: Context::compileToFile() repositions builder for every standalone-main emission via dedicated standalone_main BB; HttpResponseRuntime::implement() saves/restores insert block and early-returns when bridges exist; emitResetForStandaloneMain() no longer calls ensureLinked().
• Nested helper ABI: JitNestedHelperCoerce + JitVmHelperLink bridge arg/return coercion; alignRetvalToLlvmFnReturn for typed static/pending-return paths; ListUnpackRuntime/StreamSyncJit/SessionEncodeRuntime bridge fixes.

Verification

./script/docker-exec.sh -- bash -lc './vendor/bin/phpunit test/unit/HttpResponseCodeRuntimeShrinkTest.php'
# OK (5 tests, 17 assertions)

./script/docker-exec.sh -- bash -lc './script/examples-aot-smoke.sh'
# Still fails — verify errors reduced vs master parentless failure; remaining:
#   Terminator found in the middle of a basic block! label %try_merge_27788
#   SessionEncodeJitHelper encodeWire hashtable→object ABI mismatch
#   i64/i32 return mismatches in nested helpers

Baseline: examples-aot-smoke.sh green at 1d13db7ba; red on current master (parentless globals).

Remaining (handoff)

1. try_merge_* BB gets terminator mid-block during InfoJitHelper nested compile (TryCatchHelper::compileIncludedAtEntry merge path).
2. SessionEncodeJitHelper::encodeWire — bridge passes __hashtable__*, compiled helper expects __object__*; similar __value__*/__string__* mismatches on session create-id helpers.
3. Audit other php-in-PHP JIT bridges added after 1d13db7ba for the same insert-block / ABI pattern.

[PurHur]

Maintainer review (2026-06-24): Verified bootstrap gates green on master (bootstrap-selfhost-link, helloworld, inventory 3016/3016). Re-ran targeted repro from PR description — agree this is not merge-ready while examples-aot-smoke.sh still fails on try_merge_* terminator. Good progress (verify errors down from ~50+). Handoff items in PR body match remaining blocker. Will merge once smoke is green end-to-end.

[PurHur]

claim: cursor-agent-lane-c — continuing handoff (issue #11213 / parent #11206 AOT smoke)

[PurHur]

Update (lane-B continuation)

Pushed nested-helper ABI coercion:

• JitNestedHelperCoerce::coerceArgToHelper / coerceReturnFromHelper — __value__* ↔ typed pointers, i64 scalars, object/hashtable bitcasts
• JitVmHelperLink::callCompiled — shared entry for all php-in-PHP JIT bridges
• Bulk bridge migration via script/convert-helper-calls.php (87 Builtin files)
• alignRetvalToLlvmFnReturn on main compileBlockEnd return path

Verification

./script/docker-exec.sh -- bash -lc './vendor/bin/phpunit test/unit/HttpResponseCodeRuntimeShrinkTest.php'
# OK (5 tests, 17 assertions)

./script/docker-exec.sh -- bash -lc './phpc build -o /tmp/hw /compiler/examples/000-HelloWorld/example.php'
# LLVM verify still fails (down from ~50+ mismatches to 3 classes):
#   - parentless @__compiler_get_include_path call
#   - ret i64 vs i32 in nested helper bodies
#   - try_merge_* terminator mid-block (InfoJitHelper nested compile)

examples-aot-smoke.sh not green yet — not merging until smoke passes.

[PurHur]

Update (lane C continuation)

Pushed 88c4c0cc1 with additional bridge coercion + try/catch merge work.

Changes

• Extended JitNestedHelperCoerce (callHelper, scalar/pointer coercion helpers)
• StringInfo + ReadonlyRaise bridges use coercion (fixes i1/i8 icmp + nullable string ABI)
• TryCatchHelper::beginTry: prefer open insert block; try_merge header/body split
• JIT.php: alignRetvalToLlvmFnReturn on merge-block returns; compileIncludedAtEntry insert-block guard

Verification

./script/docker-exec.sh -- bash -lc './vendor/bin/phpunit test/unit/HttpResponseCodeRuntimeShrinkTest.php'
# OK (5 tests, 17 assertions)

./script/docker-exec.sh -- bash -lc './script/examples-aot-smoke.sh'
# Still fails LLVM verify — try_merge / nested-helper i32/i64 returns / phi-not-in-block in ProgressNoteJitHelper compile

Next steps

1. Finish SessionEncode / date builtin bridges (callHelper + coerceToHashtablePtr) — same pattern as StringInfo
2. Debug try_merge_body_* showing unreachable only — merge CFG not lowering into body BB
3. Re-run smoke until green, then merge

[PurHur]

Maintainer triage (local verify): not merging — smoke still red per PR verification block.

Re-ran mandatory bootstrap gates on master workspace: bootstrap-selfhost-link + bootstrap-selfhost-helloworld both green (gen-0 sidecar path).

HttpResponseCodeRuntimeShrinkTest not re-run this pass; merge blocked until ./script/examples-aot-smoke.sh is green vs the three remaining handoff items (try_merge BB, SessionEncode hashtable→object ABI, nested-helper return coercion audit).

[PurHur]

Lane B continuation (df95506a3)

Widens nested-helper ABI coercion beyond the initial HttpResponse/try_merge fixes.

Changes

• JitNestedHelperCoerce: coerceBridgeResult, i8→i64 arg/return coercion
• JitVmHelperLink: always coerceArgForHelper + coerceBridgeResult
• Bridges: StringGetdate, StringLocaltime, StringGmgetdate, SessionEncodeRuntime, SessionCreateIdRuntime use callHelper + typed result extractors
• IncludePathRuntime / StringInfo: save+restore LLVM insert block after ensureLinked (fixes parentless __compiler_get_include_path under IniRuntime)
• JIT::alignRetvalToLlvmFnReturn: fallback to functionReturnType when LLVM sig missing; pointer/int catch-all

Verification (Docker ./script/docker-exec.sh)

./vendor/bin/phpunit test/unit/HttpResponseCodeRuntimeShrinkTest.php
# OK (5 tests, 17 assertions)

./script/examples-aot-smoke.sh
# FAIL — improved vs master parentless globals; remaining LLVM verify:
#   ret __object__* vs __hashtable__* (1 fn)
#   ret i64 vs i32 (3 fn)
#   terminator mid-block label %block_917

Master baseline still fails earlier with parentless session/progress globals.

Next

• Identify the 4 mis-typed return functions (likely compiled php-in-PHP helpers bypassing alignRetval)
• Seal %block_917 — probably insert-block restore missing in another Type/String_.php implement() callee

[PurHur]

Update — LLVM verify + link green (runtime handoff)

Pushed commit 2ba2764b9 extending nested-helper ABI coercion across date/session/include-path/meta-tags/stream-filter bridges, try-branch terminator guard, and phpc_fn_static_init_table zeroinit.

Verification

./script/docker-exec.sh -- bash -lc './script/examples-aot-smoke.sh'
# 000-HelloWorld: phpc build OK (LLVM verify + link pass)
# binary exit 139 — segfault after `c:main_before_init`

./script/docker-exec.sh -- bash -lc 'php bin/vm.php examples/000-HelloWorld/example.php'
# Hello World

Not merging — issue acceptance requires examples-aot-smoke.sh exit 0 (runtime segfault during initFunc remains).