## Summary Implemented fail-fast validation for PHI ordering and value resolution in strict mode. ## Changes ### P1-1: Strict mode for "PHI after terminator" - File: `src/llvm_py/phi_wiring/wiring.py::ensure_phi` - Behavior: `NYASH_LLVM_PHI_STRICT=1` → RuntimeError if PHI created after terminator - Default: Warning only (no regression) ### P1-2: Strict mode for "fallback 0" - File: `src/llvm_py/phi_wiring/wiring.py::wire_incomings` - Behavior: Strict mode forbids silent fallback to 0 (2 locations) - Location 1: Unresolvable incoming value - Location 2: Type coercion failure - Error messages point to next debug file: `llvm_builder.py::_value_at_end_i64` ### P1-3: Connect verify_phi_ordering() to execution path - File: `src/llvm_py/builders/function_lower.py` - Behavior: Verify PHI ordering after all instructions emitted - Debug mode: Shows "✅ All N blocks have correct PHI ordering" - Strict mode: Raises RuntimeError with block list if violations found ## Testing ✅ Test 1: strict=OFF - passes without errors ✅ Test 2: strict=ON - passes without errors (no violations in test fixtures) ✅ Test 3: debug mode - verify_phi_ordering() connected and running ## Scope - LLVM harness (Python) changes only - No new environment variables (uses existing 3 from Phase 277 P2) - No JoinIR/Rust changes (root fix is Phase 279) - Default behavior unchanged (strict mode opt-in) ## Next Steps - Phase 278: Remove deprecated env var support - Phase 279: Root fix - unify "2本のコンパイラ" pipelines 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
Investigations Folder
This folder contains investigation notes and analysis for debugging sessions.
Active Investigations
Phase 131-12: LLVM Wrong Result (Case C)
Status: ✅ Root cause identified Problem: LLVM backend returns wrong results for loop exit values Root Cause: vmap object identity mismatch between Pass A and Pass C
Key Documents:
- phase131-12-case-c-llvm-wrong-result.md - Initial investigation scope
- phase131-12-p1-vmap-identity-analysis.md - Detailed trace analysis
- phase131-12-p1-trace-summary.md - Executive summary with fix recommendations
Quick Summary:
- Bug: Pass A deletes
_current_vmapbefore Pass C runs - Impact: Terminators use wrong vmap object, missing all Pass A writes
- Fix: Store vmap_cur in deferred_terminators tuple (Option 3)
Next Steps:
- Implement Option 3 fix in block_lower.py
- Add Fail-Fast check in instruction_lower.py
- Verify with NYASH_LLVM_VMAP_TRACE=1
- Run full test suite
Trace Environment Variables
Phase 131-12-P1 Traces
NYASH_LLVM_VMAP_TRACE=1 # Object identity and vmap keys tracing
NYASH_LLVM_USE_HARNESS=1 # Enable llvmlite harness
NYASH_LLVM_DUMP_IR=<path> # Save LLVM IR to file
Investigation Workflow
- Scope - Define problem and test case (phase131-12-case-c-*.md)
- Trace - Add instrumentation and collect data (phase131-12-p1-vmap-identity-*.md)
- Analysis - Identify root cause with evidence (phase131-12-p1-trace-summary.md)
- Fix - Implement solution with validation
- Document - Update investigation notes with results
Archive
Completed investigations are kept for reference and pattern recognition.
JoinIR Generalization Study (Historical)
joinir-generalization-study.md(Phase 131–138 の状況と一般化案の相談用コンテキスト。SSOT は design/ を参照)