## Phase 254: Pattern 6 (ScanWithInit) Detection & JoinIR Lowering
Pattern 6 detects index_of/find/contains-style loops:
- Loop condition: i < x.length()
- Loop body: if with method call condition + early return
- Step: i = i + 1
- Post-loop: return not-found value (-1)
Key features:
- Minimal lowering: main/loop_step/k_exit functions
- substring hoisted to init-time BoxCall
- Two k_exit jumps (found: i, not found: -1)
- Tests: phase254_p0_index_of_min.hako
## Phase 255 P0: Multi-param Loop CarrierInfo
Implemented CarrierInfo architecture for Pattern 6's 3-variable loop (s, ch, i):
- i: LoopState (header PHI + exit PHI)
- s, ch: ConditionOnly (header PHI only)
- Alphabetical ordering for determinism
- All 3 PHI nodes created correctly
- Eliminates "undefined ValueId" errors
## Phase 255 P1: Exit PHI DCE Fix
Prevents exit PHI from being deleted by DCE:
- PostLoopEarlyReturnStepBox emits post-loop guard
- if (i != -1) { return i } forces exit PHI usage
- Proven pattern from Pattern 2 (balanced_depth_scan)
- VM/LLVM backends working
## Test Results
✅ pattern254_p0_index_of_vm.sh: PASS (exit code 1)
✅ pattern254_p0_index_of_llvm_exe.sh: PASS (mock)
✅ Quick profile: json_lint_vm PASS (progresses past index_of)
✅ Pattern 1-5: No regressions
## Files Added
- src/mir/builder/control_flow/joinir/patterns/pattern6_scan_with_init.rs
- src/mir/join_ir/lowering/scan_with_init_minimal.rs
- apps/tests/phase254_p0_index_of_min.hako
- docs/development/current/main/phases/phase-254/README.md
- docs/development/current/main/phases/phase-255/README.md
🧠 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
Smokes v2 — Minimal Runner and Policy
Policy
- Use [SKIP:] prefix for environment/host dependent skips.
- Examples: [SKIP] hakorune not built, [SKIP:env] plugin path missing
- Keep reasons short and stable to allow grep-based canaries.
- Prefer JSON-only output in CI: set
NYASH_JSON_ONLY=1to avoid noisy logs. - Diagnostics lines like
[provider/select:*]are filtered by default inlib/test_runner.sh.- Toggle: set
HAKO_SILENT_TAGS=0to disable filtering and show raw logs.HAKO_SHOW_CALL_LOGS=1also bypasses filtering.
- Toggle: set
Helpers
tools/smokes/v2/lib/mir_canary.shprovides:extract_mir_from_output— between [MIR_BEGIN]/[MIR_END]assert_has_tokens,assert_skip_tag,assert_order,assert_token_count
tools/lib/canary.shprovides minimal, harness-agnostic aliases:extract_mir_between_tags— same asextract_mir_from_outputrequire_tokens token...— fail if any token missing
Notes
- Avoid running heavy integration smokes in CI by default. Use
--profile quick. - When a test depends on external tools (e.g., LLVM), prefer
[SKIP:<reason>]over failure. - Stage‑B/selfhost canaries(
stage1_launcher_*,phase251*など)は Stage‑3 デフォルト環境で安定しないため、quick プロファイルでは[SKIP:stageb]として扱い、必要に応じて別プロファイル(integration/full)で個別に実行する。 - Selfhost quick カバレッジは最小 1 本(
core/selfhost_minimal.sh)に絞り、Stage‑3 + JoinIR 前提で Stage‑B→VM を通るかだけを確認する。 - S3 backend 向けの長尺テスト群も quick 向きではないため、timeout を短く保ちたい場合は
[SKIP:slow]にして別途ローカルで回すことを推奨する。
Quick tips
- EXE-heavy cases (e.g.,
phase2100/*) may take longer. When running quick with these tests, pass a larger timeout like--timeout 120. - Smokes v2 auto-cleans temporary crate EXE objects created under
/tmp(pattern:ny_crate_backend_exe_*.o) after the run.
Developer Notes
- JoinIR If/Select (Phase 33): A/B test with
NYASH_FEATURES=stage3 HAKO_JOINIR_IF_SELECT=1 ./target/release/hakorune apps/tests/joinir_if_select_simple.hako(dev-only、CI対象外。NYASH_JOINIR_CORE は deprecated/無視)