phase29aa: RcPlan + guard no cleanup on jump/branch

docs/development/current/main/10-Now.md

@@ -1,9 +1,9 @@
 # Self Current Task — Now (main)
 
-## Current Focus: Phase 29aa P1（RcPlan 2-stage, meaning-preserving）
+## Current Focus: Phase 29aa P2（No cleanup on Jump/Branch）
 
-**2025-12-27: Phase 29aa P1 完了** ✅
-- 目的: rc_insertion を RcPlan に閉じ込め、Plan→Apply 2-stage 化（挙動不変）
+**2025-12-27: Phase 29aa P2 完了** ✅
+- 目的: Jump/Branch 終端で cleanup を入れない契約を SSOT 化（Fail-Fast guard）
 - 入口: `docs/development/current/main/phases/phase-29aa/README.md`
 
 **2025-12-27: Phase 29z P2 closeout** ✅

docs/development/current/main/30-Backlog.md

@@ -68,9 +68,8 @@ Related:
   - 入口: `docs/development/current/main/phases/phase-29z/README.md`
   - 指示書: `docs/development/current/main/phases/phase-29z/P0-RC_INSERTION_MINIMAL-INSTRUCTIONS.md`
 
-- **Phase 29aa（P1 COMPLETE）: RC insertion safety expansion（CFG-aware）**
-  - 進捗: P1 ✅ 完了（RcPlan 導入＋Plan→Apply 2-stage化、挙動不変）
-  - 次（P2）: CFG-aware の最小ターゲットを 1 個に絞る（例: edge cleanup を Return 以外でどう扱うか）
+- **Phase 29aa（P2 COMPLETE）: RC insertion safety expansion（CFG-aware）**
+  - 進捗: P2 ✅ 完了（Jump/Branch 終端で cleanup を入れない契約の SSOT 化）
   - 入口: `docs/development/current/main/phases/phase-29aa/README.md`
 
 - **Phase 29x（planned, post self-host）: De-Rust runtime for LLVM execution**

docs/development/current/main/phases/phase-29aa/README.md

@@ -1,6 +1,6 @@
 # Phase 29aa: RC insertion safety expansion（CFG-aware design）
 
-Status: P1 Complete (RcPlan 2-stage)  
+Status: P2 Complete (No cleanup on Jump/Branch)  
 Scope: Phase 29z の単一block限定実装から、誤releaseを起こさない形で CFG-aware に拡張するための設計を固める。  
 
 Entry:
@@ -21,3 +21,4 @@ Deliverables (P0):
 Progress:
 - P0: CFG-aware 設計の固定（RcPlan/危険パターン/安全条件の契約）
 - P1: rc_insertion を RcPlan の Plan→Apply 2-stage へ分離（挙動不変）
+- P2: Jump/Branch 終端では cleanup を入れない契約を SSOT 化（Fail-Fast guard）

src/bin/rc_insertion_selfcheck.rs

@@ -131,7 +131,7 @@ fn main() {
         "return_cleanup",
     );
 
-    // Case 4: Branch terminator should NOT inject block-end cleanup (unsafe cross-block)
+    // Case 4: Jump terminator should NOT inject block-end cleanup (unsafe cross-block)
     let ptr = ValueId::new(400);
     let v1 = ValueId::new(30);
 
@@ -144,7 +144,33 @@ fn main() {
     });
     block.terminator_span = Some(Span::unknown());
     let entry = block.id;
-    let module = build_module_with_block(block, "selfcheck_branch_skip", "selfcheck_mod4");
+    let module = build_module_with_block(block, "selfcheck_jump_skip", "selfcheck_mod4");
+    assert_release_inserted(
+        module,
+        "selfcheck_jump_skip",
+        entry,
+        0,
+        "jump_no_cleanup",
+    );
+
+    // Case 5: Branch terminator should NOT inject block-end cleanup (unsafe cross-block)
+    let ptr = ValueId::new(500);
+    let v1 = ValueId::new(40);
+    let cond = ValueId::new(41);
+
+    let mut block = BasicBlock::new(BasicBlockId::new(0));
+    block.instructions = vec![MirInstruction::Store { value: v1, ptr }];
+    block.instruction_spans = vec![Span::unknown()];
+    block.terminator = Some(MirInstruction::Branch {
+        condition: cond,
+        then_bb: BasicBlockId::new(1),
+        else_bb: BasicBlockId::new(2),
+        then_edge_args: None,
+        else_edge_args: None,
+    });
+    block.terminator_span = Some(Span::unknown());
+    let entry = block.id;
+    let module = build_module_with_block(block, "selfcheck_branch_skip", "selfcheck_mod5");
     assert_release_inserted(
         module,
         "selfcheck_branch_skip",

src/mir/passes/rc_insertion.rs

@@ -267,16 +267,19 @@ fn apply_rc_plan(
     }
 
     if !drops_before_terminator.is_empty() {
-        if !drops_before_terminator.is_empty() {
-            let span = terminator_span.clone().unwrap_or_else(Span::unknown);
-            for drop_site in drops_before_terminator {
-                let _ = drop_site.reason;
-                new_insts.push(MirInstruction::ReleaseStrong {
-                    values: drop_site.values,
-                });
-                new_spans.push(span.clone());
-                stats.release_inserted += 1;
-            }
+        debug_assert!(
+            matches!(terminator, Some(MirInstruction::Return { .. })),
+            "rc_insertion: ReturnCleanup planned for non-Return terminator"
+        );
+
+        let span = terminator_span.clone().unwrap_or_else(Span::unknown);
+        for drop_site in drops_before_terminator {
+            let _ = drop_site.reason;
+            new_insts.push(MirInstruction::ReleaseStrong {
+                values: drop_site.values,
+            });
+            new_spans.push(span.clone());
+            stats.release_inserted += 1;
         }
     }