# TICKET-PMAT-7002: Enhanced WASM Deep Inspection Implementation

**Status**: ✅ COMPLETE
**Priority**: High
**Complexity**: Medium (6-9 days estimated, 4 hours actual)
**Sprint**: Sprint 23
**Created**: 2025-10-07
**Completed**: 2025-10-07
**Issue**: https://github.com/paiml/paiml-mcp-agent-toolkit/issues/65

## Objective

Implement detailed WASM bytecode analysis for compiler development, enabling function-level and instruction-level inspection of WebAssembly binaries.

## Requirements

### Function-Level Analysis
- [x] Extract and display function signatures (params, returns, type indices)
- [x] Calculate complexity metrics per function (cyclomatic, branches, loops, calls)
- [x] Count instructions per function
- [x] Analyze stack depth per function (max, avg, entry, exit)
- [x] Identify control flow patterns

### Instruction-Level Details
- [x] Implement function disassembly with mnemonics and operands
- [x] Provide instruction type breakdown by category
- [x] Detect suspicious code patterns (dead code, infinite loops, excessive stack ops, deep nesting)
- [x] Show instruction-level metrics (stack effect, cost estimation)
- [x] Build basic blocks for control flow analysis

### Advanced Features
- [x] Track and report validation errors with context
- [x] Map source expressions to bytecode (via existing DWARF/source map integration)
- [x] Analyze import/export functions with full type signatures
- [x] Generate detailed debug reports

## Implementation

### Files Created (1,650 lines)
1. `server/src/services/deep_wasm/bytecode_analyzer.rs` (920 lines)
   - BytecodeAnalyzer for module-wide analysis
   - FunctionAnalysis with comprehensive metrics
   - ComplexityMetrics, InstructionStats, StackDepthAnalysis
   - ImportAnalysis, ExportAnalysis, ValidationError types
   - ModuleBytecodeAnalysis with module-wide statistics

2. `server/src/services/deep_wasm/disassembler.rs` (730 lines)
   - Disassembler with pattern detection
   - DisassembledInstruction with stack effects and cost estimates
   - InstructionPattern detection (4 suspicious patterns)
   - BasicBlock construction for control flow
   - Category classification and formatting

### Files Modified
- `server/src/services/deep_wasm/mod.rs` - Added module exports
- `server/src/services/deep_wasm/types.rs` - Extended DeepWasmReport with bytecode_analysis, disassembled_functions, suspicious_patterns
- `server/src/services/deep_wasm/service.rs` - Integrated bytecode analysis with configurable deep analysis mode

### Documentation
- `docs/features/WASM_DEEP_INSPECTION_ISSUE_65.md` - Comprehensive feature documentation

## Testing

- [x] bytecode_analyzer::tests - 4 unit tests
- [x] disassembler::tests - 5 unit tests
- [x] Integration with existing deep_wasm service tests
- [x] Validates minimal WASM modules
- [x] Stack effect calculation tests
- [x] Pattern detection validation

## Deliverables

✅ Function signatures with full type information
✅ Complexity metrics (cyclomatic, instruction count, branches, loops, calls, nesting)
✅ Instruction statistics with category breakdown
✅ Stack depth analysis (max, avg, entry, exit)
✅ Control flow pattern detection with suspicion flagging
✅ Import/export analysis with type signatures
✅ Validation error tracking
✅ Suspicious pattern detection (dead code, infinite loops, stack abuse, deep nesting)
✅ Basic block identification
✅ Configurable deep/shallow analysis modes

## Success Criteria

- [x] All code compiles without errors
- [x] All tests pass
- [x] Function-level metrics available for all functions
- [x] Instruction-level disassembly working
- [x] Pattern detection identifies suspicious code
- [x] Import/export analysis complete
- [x] Documentation complete
- [x] Performance acceptable (<500ms for typical modules)

## Value Delivered

**Before**: Only high-level WASM metrics (function count, module size)
**After**: Complete bytecode-level analysis for compiler debugging
**Use Case**: Ruchy → WASM compiler development and debugging
**ROI**: Critical for compiler development workflows

## Actual Effort

4 hours (vs 6-9 days estimated) - Significantly faster due to leveraging existing wasmparser infrastructure

## Notes

- Uses wasmparser 0.239.0 with RecGroup API
- Zero-copy parsing where possible for performance
- Deep analysis mode optional (configurable for performance)
- Pattern detection automatically flags suspicious code
- Ready for production use in compiler development workflows
