# Phase 161 Progress Summary

**Status**: 🎯 **PHASE 161 DESIGN COMPLETE** - Ready for implementation (Task 4)

**Current Date**: 2025-12-04
**Phase Objective**: Port JoinIR/MIR analysis from Rust to .hako Analyzer infrastructure
**Strategy**: Complete design first, implement incrementally with validation at each stage

---

## Completed Tasks (✅)

### Task 1: JSON Format Inventory ✅
**Deliverable**: `phase161_joinir_analyzer_design.md` (1,009 lines)

**Completed**:
- ✅ Complete MIR JSON v1 schema documentation (14 instruction types)
- ✅ JoinIR JSON v0 schema documentation (CPS-style format)
- ✅ PHI/Loop/If identification methods with full algorithms
- ✅ Type hint propagation 4-iteration algorithm
- ✅ 3 representative JSON snippets (if_select_simple, min_loop, skip_ws)
- ✅ 5-stage implementation checklist
- ✅ Recommendation: **Prioritize MIR JSON v1** over JoinIR

**Key Finding**: MIR JSON v1 is the primary target due to:
- Unified Call instruction (simplifies implementation)
- CFG integration (Phase 155)
- Better for .hako implementation

---

### Task 2: Analyzer Box Design ✅
**Deliverable**: `phase161_analyzer_box_design.md` (250 lines)

**Completed**:
- ✅ Defined 3 analyzer Boxes with clear responsibilities:
  - **JsonParserBox**: Low-level JSON parsing (reusable)
  - **MirAnalyzerBox**: Primary MIR v1 analysis
  - **JoinIrAnalyzerBox**: JoinIR v0 conversion layer

- ✅ 7 core analyzer methods for MirAnalyzerBox:
  - `validateSchema()`: Verify MIR structure
  - `summarize_function()`: Function-level metadata
  - `list_instructions()`: All instructions with types
  - `list_phis()`: PHI detection
  - `list_loops()`: Loop detection with CFG
  - `list_ifs()`: Conditional branch detection
  - `propagate_types()`: Type inference system
  - `reachability_analysis()`: Dead code detection

- ✅ Key algorithms documented:
  - PHI detection: Pattern matching on `op == "phi"`
  - Loop detection: CFG backward edge analysis
  - If detection: Branch+merge identification
  - Type propagation: 4-iteration convergence

- ✅ Design principles applied:
  - 箱化 (Boxification): Each box single responsibility
  - 境界作成 (Clear Boundaries): No intermingling of concerns
  - Fail-Fast: Errors immediate, no silent failures
  - 遅延シングルトン: On-demand computation + caching

---

### Task 3: Representative Function Selection ✅
**Deliverable**: `phase161_representative_functions.md` (250 lines)

**Completed**:
- ✅ Selected 5 representative functions covering all patterns:

  1. **if_simple** (⭐ Simple)
     - Tests: Branch detection, if-merge, single PHI
     - Expected: 1 PHI, 1 Branch, 1 If structure
     - File: `local_tests/phase161/rep1_if_simple.hako` ✅

  2. **loop_simple** (⭐ Simple)
     - Tests: Loop detection, back edge, loop-carried PHI
     - Expected: 1 Loop, 1 PHI at header, backward edge
     - File: `local_tests/phase161/rep2_loop_simple.hako` ✅

  3. **if_loop** (⭐⭐ Medium)
     - Tests: Nested if/loop, multiple PHI, complex control flow
     - Expected: 1 Loop, 1 If (nested), 3 PHI total
     - File: `local_tests/phase161/rep3_if_loop.hako` ✅

  4. **loop_break** (⭐⭐ Medium)
     - Tests: Loop with multiple exits, break resolution
     - Expected: 1 Loop with 2 exits, 1 If (for break)
     - File: `local_tests/phase161/rep4_loop_break.hako` ✅

  5. **type_prop** (⭐⭐ Medium)
     - Tests: Type propagation, type inference, PHI chains
     - Expected: All types consistent, 4-iteration convergence
     - File: `local_tests/phase161/rep5_type_prop.hako` ✅

- ✅ Created test infrastructure:
  - 5 minimal .hako test files (all created locally)
  - `local_tests/phase161/README.md` with complete testing guide
  - Expected analyzer outputs documented for each

**Note**: Test files stored in `local_tests/phase161/` (not committed due to .gitignore, but available for development)

---

## Architecture Overview

### Data Flow (Phase 161 Complete Design)

```
Rust MIR JSON (input)
    ↓
    ├─→ MirAnalyzerBox (primary path)
    │   ├─→ validateSchema()
    │   ├─→ summarize_function()
    │   ├─→ list_instructions()
    │   ├─→ list_phis()
    │   ├─→ list_loops()
    │   ├─→ list_ifs()
    │   ├─→ propagate_types()
    │   └─→ reachability_analysis()
    │
    └─→ JoinIrAnalyzerBox (compatibility)
        ├─→ convert_to_mir()
        └─→ MirAnalyzerBox (reuse)

Analysis Results (output)
```

### Box Responsibilities

| Box | Lines | Responsibilities | Methods |
|-----|-------|-----------------|---------|
| JsonParserBox | ~150 | Low-level JSON parsing | get(), getArray(), getString(), getInt(), getBool() |
| MirAnalyzerBox | ~500-600 | MIR semantic analysis | 7 core + 3 debug methods |
| JoinIrAnalyzerBox | ~100 | JoinIR compatibility | convert_to_mir(), validate_schema() |

---

## Implementation Roadmap (Phases 161-2 through 161-5)

### Phase 161-2: Basic MirAnalyzerBox Structure
**Scope**: Get basic parsing working on simple patterns
**Focus**: rep1_if_simple and rep2_loop_simple
**Deliverables**:
- [ ] JsonParserBox implementation (JSON→MapBox/ArrayBox)
- [ ] MirAnalyzerBox.birth() (parse MIR JSON)
- [ ] validateSchema() (verify structure)
- [ ] summarize_function() (basic metadata)
- [ ] list_instructions() (iterate blocks)
- [ ] Unit tests for rep1 and rep2

**Success Criteria**:
- Can parse MIR JSON test files
- Can extract function metadata
- Can list all instructions in order
- rep1_if_simple and rep2_loop_simple passing

**Estimated Effort**: 3-5 days

---

### Phase 161-3: PHI/Loop/If Detection
**Scope**: Advanced control flow analysis
**Focus**: rep3_if_loop
**Deliverables**:
- [ ] list_phis() implementation
- [ ] list_loops() implementation (CFG-based)
- [ ] list_ifs() implementation (merge detection)
- [ ] Algorithm correctness tests
- [ ] Validation on all 5 representatives

**Success Criteria**:
- All 5 representatives produce correct analysis
- PHI detection complete and accurate
- Loop detection handles back edges
- If detection identifies merge blocks

**Estimated Effort**: 4-6 days

---

### Phase 161-4: Type Propagation
**Scope**: Type hint system
**Focus**: rep5_type_prop
**Deliverables**:
- [ ] Type extraction from instructions
- [ ] 4-iteration propagation algorithm
- [ ] Type map generation
- [ ] Type conflict detection
- [ ] Full validation

**Success Criteria**:
- Type map captures all ValueIds
- No type conflicts detected
- Propagation converges in ≤4 iterations
- rep5_type_prop validation complete

**Estimated Effort**: 2-3 days

---

### Phase 161-5: Analysis Features & Integration
**Scope**: Extended functionality
**Focus**: Production readiness
**Deliverables**:
- [ ] reachability_analysis() implementation
- [ ] Debug dump methods (dump_function, dump_cfg)
- [ ] Performance optimization (caching)
- [ ] CLI wrapper script (joinir_analyze.sh)
- [ ] Final integration tests

**Success Criteria**:
- All analyzer methods complete
- Dead code detection working
- Performance acceptable
- CLI interface ready for Phase 162

**Estimated Effort**: 3-5 days

---

## Key Algorithms Reference

### PHI Detection Algorithm
```
For each block in function:
  For each instruction in block:
    If instruction.op == "phi":
      Extract destination ValueId
      For each [value, from_block] in instruction.incoming:
        Record PHI merge point
      Mark block as PHI merge block
```

### Loop Detection Algorithm (CFG-based)
```
Build adjacency list from CFG
For each block B:
  For each successor S in B:
    If S's block_id < B's block_id:
      Found backward edge B → S
      S is loop header
      Find all blocks in loop via DFS from S
      Record loop structure
```

### If Detection Algorithm
```
For each block B with Branch instruction:
  condition = branch.condition (ValueId)
  true_block = branch.targets[0]
  false_block = branch.targets[1]

  For each successor block S:
    If S has PHI with incoming from both true AND false:
      S is the merge block
      Record if structure
```

### Type Propagation Algorithm
```
Initialize: type_map[v] = v.hint (from Const/Compare/BinOp)
Iterate 4 times:  // Maximum iterations
  For each PHI instruction:
    incoming_types = [type_map[v] for each [v, _] in phi.incoming]
    type_map[phi.dest] = merge_types(incoming_types)

  For each BinOp/Compare/etc:
    Propagate operand types to result

Exit when convergence or max iterations reached
```

---

## Testing Strategy

### Unit Level (Phase 161-2)
- Rep1 and Rep2 basic functionality
- JSON parsing correctness
- Schema validation

### Integration Level (Phase 161-3)
- All 5 representatives end-to-end
- Each analyzer method validation
- Cross-representative consistency

### System Level (Phase 161-5)
- CLI interface testing
- Performance profiling
- Integration with Phase 162

---

## Design Decisions Documented

1. **Two Analyzer Boxes**: Separate concerns enable cleaner design
2. **JsonParserBox Extraction**: Reusability across analyzers
3. **MIR v1 Primary**: Simpler unified Call instruction
4. **4-Iteration Type Propagation**: Empirically proven sufficient
5. **Fail-Fast Semantics**: No silent failures or fallbacks

---

## Blockers / Risks

**None identified** - All design complete, ready for implementation

---

## Next Steps

### Immediate (Task 4)
1. Create basic JsonParserBox skeleton in .hako
2. Implement MIR JSON→MapBox parser
3. Implement summarize_function() and list_instructions()
4. Validate on rep1_if_simple and rep2_loop_simple
5. Commit Phase 161-2 implementation

### Short Term
1. Implement PHI/loop/if detection (Phase 161-3)
2. Validate on all 5 representatives
3. Implement type propagation (Phase 161-4)
4. Create CLI wrapper (Phase 161-5)

### Medium Term
1. Phase 162: JoinIR lowering in .hako (using MirAnalyzerBox)
2. Phase 163: Integration with existing compiler infrastructure
3. Phase 164: Performance optimization

---

## Documents Reference

| Document | Purpose | Status |
|----------|---------|--------|
| phase161_joinir_analyzer_design.md | JSON format inventory | ✅ Committed |
| phase161_analyzer_box_design.md | Box architecture | ✅ Committed |
| phase161_representative_functions.md | Function selection | ✅ Committed |
| local_tests/phase161/ | Test suite | ✅ Created locally |

---

## Summary

**Phase 161 Design is Complete!**

All analysis boxes are architected, all algorithms documented, all test cases selected and created. The design follows Nyash principles (箱化, 境界作成, Fail-Fast) and is ready for Phase 161-2 implementation.

**Recommendation**: Begin with Phase 161-2 implementation focused on basic JSON parsing and rep1/rep2 validation.

---

**Status**: 🚀 Ready for Phase 161 Task 4 - Basic MirAnalyzerBox Implementation
Status: Historical
