f0608e9bb1
## 🎉 完了項目 - ✅ plugin_box_legacy.rs削除（7.7KB、参照ゼロ確認済み） - ✅ REMOVEDコメント整理（encode.rs簡潔化） - ✅ venv削除（143MB節約、.gitignoreは既存） - ✅ llvm_legacyスタブ化（8KB、compile_error!による安全化） ## 🏆 成果 - **リポジトリサイズ改善**: 151MB削減 - **コード整理**: レガシーコード安全にアーカイブ - **プラグインファースト**: StrictPluginFirst継続動作 ## ✅ 検証完了 - cargo build --release --features llvm (警告のみ、エラーなし) - LLVMハーネス実行: print出力正常 - プラグイン動作: StringBox等正常動作 codex先生の戦略に従った安全な段階的削除を実行 Co-Authored-By: codex <noreply@anthropic.com>
50 lines
2.9 KiB
Markdown
50 lines
2.9 KiB
Markdown
MIR13 Mode (legacy PHI-off fallback)
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Overview
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- Goal: Retain the Phase‑14 edge-copy compatibility path for debugging historical MIR dumps or diagnosing SSA regressions.
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- Default: MIR14 (PHI-on) now ships as the standard. MIR13 must be explicitly enabled through environment flags.
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Why keep MIR13 around?
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- Reproducibility: Some archived JSON v0 fixtures were captured before PHI-on shipped. MIR13 allows replaying them without regeneration.
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- Diagnostics: Edge-copy runs make it easier to isolate builder regressions by removing PHI synthesis from the equation.
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- Tooling parity: Certain scripts still compare MIR13 traces; they will be retired once PHI-on parity checks are complete.
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Flags and Behavior
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- NYASH_MIR_NO_PHI (default: 0)
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- 0: Builders emit PHIs at merge heads (MIR14, default).
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- 1: Builders drop PHIs and insert per-predecessor edge copies (MIR13 fallback).
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- NYASH_VERIFY_ALLOW_NO_PHI (default: 0 unless PHI-off is requested)
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- Set this to 1 together with `NYASH_MIR_NO_PHI=1` when you intentionally relax SSA verification.
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- NYASH_LLVM_USE_HARNESS=1 (AOT via llvmlite harness)
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- In MIR13 mode the harness synthesizes PHIs. In MIR14 it simply validates incoming edges.
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LLVM (llvmlite) Responsibilities
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- `setup_phi_placeholders()`: still records declared PHIs; in MIR13 mode it creates placeholders for later wiring.
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- `block_end_values`: snapshots per block end to materialize predecessor values (dominance-safe).
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- `finalize_phis()`: wires incoming edges for declared PHIs; when MIR13 runs, it creates PHIs on the fly to recover SSA.
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- `Resolver.resolve_i64()`:
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- single-pred: take predecessor end value;
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- multi-pred + declared PHI: reuse the placeholder at the block head;
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- multi-pred + no PHI: synthesize a localization PHI at the current block head (MIR13 compatibility);
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- avoids reusing non-dominating vmap values across blocks.
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Bridge/Builder (JSON v0) Behavior
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- MIR14 (default): If/Loop/Try placements emit PHIs up front; loop latches, break/continue, and structured joins have explicit incoming pairs.
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- MIR13 (fallback): Merges are performed with edge copies (`merge_var_maps`). Use only when reproducing historical issues.
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Testing
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- Curated LLVM (default = PHI-on):
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- `tools/smokes/curated_llvm.sh` (add `--phi-off` to exercise MIR13)
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- PHI invariants/parity (AOT vs PyVM):
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- `tools/pyvm_vs_llvmlite.sh` (default compares exit code; use `CMP_STRICT=1` for stdout+exit)
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- Bridge/PyVM:
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- `tools/selfhost_stage2_bridge_smoke.sh`
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How to Force PHI-off (MIR13 fallback)
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- Set: `NYASH_MIR_NO_PHI=1 NYASH_VERIFY_ALLOW_NO_PHI=1` and run `tools/smokes/curated_llvm.sh --phi-off`
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- Label the run as legacy in `CURRENT_TASK.md` if results inform shared debugging.
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Known Limitations (current)
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- MIR13 no longer receives new feature work; expect missing coverage for recent LoopForm updates.
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- PHI-on is the supported path. MIR13 bugs are fixed only when they block diagnostics.
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