Self-host P0: JIT __value__ / hashtable paths for Block::scopeOperandBySlot

[PurHur]

Blocks

Native self-host compile segfaults in LLVM (LLVMBuildStructGEP) while JIT-lowering Block::findSlot and related CFG using:

• scopeOperandBySlot (array)
• ?Variable returns boxed as __value__
• isset / property fetch on array-backed scope slots

Goal

Unify JIT typing: array params → __hashtable__*, property loads via value-box slots, HashTableHelper + IssetHelper use alloca pointers not loaded struct values.

Acceptance

• php bin/compile.php -o build/selfhost test/selfhost/compiler_minimal/main.php exits 0 in Docker
• ./build/selfhost prints selfhost
• ./script/bootstrap-selfhost-link.sh OK
• README self-host section updated to Achieved (minimal subset) with date + PR

Links

• Milestone: Self-host — compile php-compiler with php-compiler (bootstrap) #212, PR Self-host: JIT fixes for bundled compiler native link (#212) #552 branch issue-selfhost-compiler-native

[PurHur]

Status (2026-05-22)

Rebased onto master (#556, #578, #579, #580 merged). PR: #577

Done

• ./script/bootstrap-selfhost-lint.sh — OK
• JIT: __value__ type mapping, null literals, VALUE/null assign coercion, external function stubs (resolveFunctionProxy), subset isset lowering

Blocker (native link)

• php bin/compile.php -o build/selfhost test/selfhost/compiler_minimal/main.php completes JIT lowering then segfaults in LLVM emit (docker php-compiler:22.04-dev and host LLVM 9)
• ./script/bootstrap-selfhost-link.sh — fails at same point

Next

• Fix LLVM crash (likely __value__readHashtable / boxed isset paths in large modules) without regressing lint
• Then README “Achieved (minimal subset)” + merge PR 577