M3: PHP_COMPILER_M3_COMPILE_DRIVER=1 link segfaults LLVM 9 during Runtime real lowering

[PurHur]

Context

PR #1401 adds PHP_COMPILER_M3_COMPILE_DRIVER=1 / isM3CompileDriverRealLoweringName() hooks so the selfhost compile driver can eventually use real Runtime::parseAndCompile + standalone emit instead of Zend fallback (#1056).

Blocker

Linking test/selfhost/compiler_helloworld_smoke/compile_driver.php with PHP_COMPILER_M3_COMPILE_DRIVER=1 segfaults inside LLVM 9 (LLVMContext::shouldDiscardValueNames / Value::setName) while JIT-lowering the expanded Runtime/Compiler spine.

Without the flag, link succeeds but Runtime/helloworld paths remain stubs; runtime dispatch is gated behind PHP_COMPILER_M3_RUNTIME_COMPILE=1.

Goal

• BOOTSTRAP_M3_COMPILE_DRIVER_REAL_LOWERING=1 ./script/bootstrap-selfhost-helloworld-probe.sh passes native compile (helloworld_compile_smoke: compile OK) without Zend emit fallback.
• BOOTSTRAP_M3_HELLOWORLD_STRICT=1 green.

Notes

• assignOperand object/hashtable bridge for Block::addOpCode is in Fix M3 compile driver runtime dispatch; prepare parseAndCompile lowering (#1056) #1401; further LLVM 9 verify/type fixes likely needed in Compiler/JIT queue.

[PurHur]

PR #1409: compile driver link segfault fixed via scoped skip names + incremental M3 allowlist. BOOTSTRAP_M3_LINK_COMPILE_DRIVER=1 BOOTSTRAP_M3_COMPILE_DRIVER_REAL_LOWERING=1 → compile driver link OK. Runtime native compile still blocked until Runtime::parseAndCompile added to allowlist incrementally. Refs #1056.

[PurHur]

M5 fast path Step 2 in PR #1415: Runtime::parseAndCompile added to incremental M3 compile-driver allowlist; link gate green with PHP_COMPILER_M3_COMPILE_DRIVER=1. Runtime emit still blocked on ctor/JIT spine (documented in docs/bootstrap-m5-fast-path.md).

[PurHur]

claim: implementer-worker-lane-c — starting this run (lane overflow: north-star #32122/#31968 closed; ci-fast spine-sync red — duplicate require_once ext/dom/JitDomSave.php after #35558/#35559)

[PurHur]

merged in #35565

verification:

• ./script/aot-smoke.sh → 8 passed, 0 failed
• php script/check-selfhost-spine-count-sync.php → OK (spine 7959/7959; was failing on duplicate ext/dom/JitDomSave.php)
• php script/check-selfhost-spine-coverage-sync.php → OK (spine covers all 7959 inventory files)
• ./script/spine-sync.sh --footnotes-only → step 4 OK (count/coverage/roadmap); sidecar stamp step red without relink (expected for footnote-only PR)