Problem:
- Pattern3 heuristic was too conservative: detect_if_in_body() returned
true for ANY if statement, causing simple conditional assignments to be
misclassified as Pattern3IfPhi
- Example: `if i == 0 then seg = "first" else seg = "other"` was routed
to Pattern3, but Pattern3 only handles if-sum patterns like
`sum = sum + (if x then 1 else 0)`
- This caused loops with conditional assignment to fail Pattern3 check
and exhaust all routing paths
Solution (Conservative, Phase 264 P0):
- ast_feature_extractor.rs:
- detect_if_else_phi_in_body(): Always return false
- has_if = has_if_else_phi (don't use detect_if_in_body())
- loop_pattern_detection/mod.rs:
- Add has_if_sum_signature() (returns false for P0)
- has_if_else_phi = carrier_count > 1 && has_if_sum_signature(scope)
Effect:
- Simple conditional assignment loops now fall through to Pattern1 ✅
- Pattern3 misrouting prevented ✅
Results:
- Lib tests: 1368/1368 PASS (no regression)
- Minimal repro: phase264_p0_bundle_resolver_loop_min.hako PASS ✅
- Quick smoke: 45/46 (unchanged - complex BundleResolver loop needs P1)
Phase 264 P1 TODO:
- Implement accurate if-sum signature detection (AST/CFG analysis)
- Support complex nested loops in Pattern2 or new pattern
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
