fix(joinir): Phase 283 P0 - Pattern3 Undefined ValueId Bug Fix

- Fix: extract_if_condition() moved after local_cond_env construction (loop_with_if_phi_if_sum.rs:175) - Root cause: condition extraction before i_param/sum_param creation - Result: i % 2 referenced caller's ConditionEnv with unmapped ValueId - Fail-Fast: Add condition_bindings validation in merge (mod.rs) - Fixture: Update loop_if_phi.hako for C2 compatibility (sum.toString()) - Verified: VM execution outputs sum=9 ✅ 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
2025-12-23 08:14:27 +09:00
parent 32ccccd272
commit bfbc9b26bf
6 changed files with 114 additions and 31 deletions
--- a/apps/tests/loop_if_phi.hako
+++ b/apps/tests/loop_if_phi.hako
@ -7,8 +7,7 @@ static box Main {
      if (i % 2 == 1) { sum = sum + i } else { sum = sum + 0 }
      i = i + 1
    }
-    console.println("sum=" + sum)
+    console.println("sum=" + sum.toString())
    return 0
  }
 }
-
--- a/docs/development/current/main/10-Now.md
+++ b/docs/development/current/main/10-Now.md
@ -2,16 +2,15 @@

 ## Current Focus (next)

- Phase 281（design-first）: `docs/development/current/main/phases/phase-281/README.md`
-  - P1 planned: Pattern6（early-exit）を compose に寄せる（挙動不変で段階移行）
-  - SSOT: `docs/development/current/main/design/edgecfg-fragments.md`, `src/mir/builder/control_flow/edgecfg/api/compose.rs`
- Phase 282（planned, design-first）: Router shrinkage
-  - pattern番号を “症状ラベル（テスト名）” に降格し、合成SSOTへ寄せた後に router を縮退させる
+- Phase 283（bugfix）: JoinIR if-condition remap fix: `docs/development/current/main/phases/phase-283/README.md`
+  - 目的: Pattern3（if-sum）で `i % 2 == 1` が undefined `ValueId` を生成する不具合を根治する
+  - SSOT: `src/mir/join_ir/lowering/loop_with_if_phi_if_sum.rs`（ConditionEnv の正しい使用位置）

 ## Recently Completed (2025-12-23)

+- Phase 282（Router shrinkage + extraction-based migration P0–P5）: `docs/development/current/main/phases/phase-282/README.md`
 - Phase 280（Frag composition SSOT positioning）: `docs/development/current/main/phases/phase-280/README.md`
- Phase 281 P0（Pattern7 → compose::if_）: `docs/development/current/main/phases/phase-281/README.md`
+- Phase 281（Pattern6/7 compose adoption, P0–P3）: `docs/development/current/main/phases/phase-281/README.md`
 - Phase 273（Plan line SSOT）: `docs/development/current/main/phases/phase-273/README.md`
 - Phase 275 P0（A1/B2/C2 coercion SSOT）: `docs/development/current/main/phases/phase-275/README.md`
 - Phase 276 P0（quick wins / type_helper SSOT）: `docs/development/current/main/phases/phase-276/README.md`
--- a/docs/development/current/main/30-Backlog.md
+++ b/docs/development/current/main/30-Backlog.md
@ -8,12 +8,9 @@ Related:

 ## 直近（JoinIR/selfhost）

- **Phase 281（planned）: Pattern6 を compose へ段階吸収**
-  - 入口: `docs/development/current/main/phases/phase-281/README.md`
-  - P0（Pattern7）✅ 完了、次は P1（Pattern6 early-exit）
-
- **Phase 282（planned）: Router shrinkage**
-  - 目的: pattern番号を “症状ラベル” に縮退させ、合成SSOTへ寄せた後に router の分岐を減らす
+- **Phase 282（planned, design-first）: Router shrinkage**
+  - 入口: `docs/development/current/main/phases/phase-282/README.md`
+  - 目的: pattern番号を “症状ラベル” に縮退し、router の責務を「抽出の配線」へ収束させる

 （✅ done）**Phase 279 P0**: Type propagation pipeline SSOT 統一（lifecycle / JoinIR / LLVM の二重化解消）
  - 完了: `docs/development/current/main/phases/phase-279/README.md`
@ -27,6 +24,12 @@ Related:
 - （✅ done）**Phase 273**: Plan line SSOT（Pattern6/7）
  - 完了: `docs/development/current/main/phases/phase-273/README.md`

+- （✅ done）**Phase 280**: Frag composition SSOT positioning
+  - 完了: `docs/development/current/main/phases/phase-280/README.md`
+
+- （✅ done）**Phase 281**: compose adoption（Pattern6/7, P0–P3）
+  - 完了: `docs/development/current/main/phases/phase-281/README.md`
+
 - （✅ done）**Phase 277/278**: PHI strict + env var 収束
  - 完了: `docs/development/current/main/phases/phase-277/README.md`
  - 完了: `docs/development/current/main/phases/phase-278/README.md`
--- a/docs/development/current/main/phases/phase-283/README.md
+++ b/docs/development/current/main/phases/phase-283/README.md
@ -0,0 +1,47 @@
+# Phase 283: JoinIR If-Condition ValueId Remap Fix
+
+Status: **P0 ✅ complete (2025-12-23)**
+
+Goal:
+- Fix a Pattern3 (if-sum) JoinIR lowering bug where complex if-conditions like `i % 2 == 1` could produce MIR that uses an undefined `ValueId`.
+
+SSOT References:
+- JoinIR lowering (if-sum): `src/mir/join_ir/lowering/loop_with_if_phi_if_sum.rs`
+- Condition value lowering: `src/mir/join_ir/lowering/condition_lowerer.rs`
+- MIR verification (undefined values): `src/mir/verification/ssa.rs`
+- Test fixture: `apps/tests/loop_if_phi.hako`
+
+## Problem
+
+Observed error (VM):
+- `use of undefined value ValueId(...)` inside the loop body, originating from the modulo expression in the if-condition.
+
+The symptom appeared in `apps/tests/loop_if_phi.hako`:
+```hako
+if (i % 2 == 1) { ... } else { ... }
+```
+
+## Root Cause
+
+In `lower_if_sum_pattern`, the if-condition was extracted (and its JoinIR value-expression lowered) **before** `i_param` / `sum_param` existed, so `Variable("i")` inside complex expressions resolved through the caller-provided `ConditionEnv`.
+
+That early `ConditionEnv` mapping could not be remapped by the boundary/merger, resulting in JoinIR ValueIds that became undefined host ValueIds in MIR.
+
+## Fix (P0)
+
+- Move `extract_if_condition(...)` so it runs **after** `local_cond_env` is constructed and shadowed:
+  - `local_cond_env.insert(loop_var, i_param)`
+  - `local_cond_env.insert(update_var, sum_param)`
+  - (and any condition bindings remapped to `main_params`)
+
+This ensures complex expressions like `i % 2` resolve `i` to `i_param` (a loop_step param that the merger remaps), preventing undefined ValueIds.
+
+## Fixture Note (Coercion SSOT)
+
+After Phase 275 (C2), implicit `"String" + Integer` is a TypeError. The fixture uses:
+- `sum.toString()` instead of `"sum=" + sum` or `str(sum)`.
+
+## Acceptance
+
+- `apps/tests/loop_if_phi.hako` runs on VM without undefined ValueId errors and prints `sum=9`.
+
--- a/src/mir/builder/control_flow/joinir/merge/mod.rs
+++ b/src/mir/builder/control_flow/joinir/merge/mod.rs
@ -239,7 +239,24 @@ pub(in crate::mir::builder) fn merge_joinir_mir_blocks(
            .flat_map(|params| params.iter().copied())
            .collect();

+        // Phase 283 P0 DEBUG: Log condition_bindings count
+        trace.stderr_if(
+            &format!(
+                "[cf_loop/joinir] Phase 283 P0 DEBUG: Processing {} condition_bindings",
+                boundary.condition_bindings.len()
+            ),
+            debug,
+        );
+
        for binding in &boundary.condition_bindings {
+            trace.stderr_if(
+                &format!(
+                    "[cf_loop/joinir] Phase 283 P0 DEBUG: Checking binding '{}' join={:?}",
+                    binding.name, binding.join_value
+                ),
+                debug,
+            );
+
            if all_params.contains(&binding.join_value) {
                trace.stderr_if(
                    &format!(
@ -249,14 +266,27 @@ pub(in crate::mir::builder) fn merge_joinir_mir_blocks(
                    debug,
                );
            } else {
-                trace.stderr_if(
-                    &format!(
-                        "[cf_loop/joinir] Phase 171-fix: Adding condition binding '{}' JoinIR {:?} to used_values",
+                // Phase 283 P0 FIX: Ensure remapper has valid mapping (Fail-Fast)
+                if let Some(host_id) = builder.variable_ctx.variable_map.get(&binding.name) {
+                    // Variable exists in host context - map join_value to existing host_id
+                    trace.stderr_if(
+                        &format!(
+                            "[cf_loop/joinir] Phase 283 P0: ✅ Condition binding '{}' JoinIR {:?} → host {:?}",
+                            binding.name, binding.join_value, host_id
+                        ),
+                        debug,
+                    );
+                    remapper.set_value(binding.join_value, *host_id);
+                    used_values.insert(binding.join_value);
+                } else {
+                    // Fail-Fast: No host ValueId found → surface root cause immediately
+                    return Err(format!(
+                        "[merge/phase2.1] Condition variable '{}' (join={:?}) has no host ValueId in variable_map. \
+                        This indicates the value was not properly supplied by boundary builder or cond_env. \
+                        Check: (1) boundary builder supplies all condition vars, (2) cond_env correctly tracks host ValueIds.",
                        binding.name, binding.join_value
-                    ),
-                    debug,
-                );
-                used_values.insert(binding.join_value);
+                    ));
+                }
            }
        }

--- a/src/mir/join_ir/lowering/loop_with_if_phi_if_sum.rs
+++ b/src/mir/join_ir/lowering/loop_with_if_phi_if_sum.rs
@ -102,16 +102,6 @@ pub fn lower_if_sum_pattern(
        &format!("{} {:?} ValueId({})", loop_var, loop_op, loop_limit_val.0)
    );

-    // Step 2: Extract if condition info (e.g., i > 0 → var="i", op=Gt, value=ValueId)
-    // Phase 220-D: Now returns ValueId and instructions
-    // Phase 242-EX-A: Now supports complex LHS
-    let (if_var, if_op, if_lhs_val, if_value_val, if_value_insts) =
-        extract_if_condition(if_stmt, &mut alloc_value, cond_env)?;
-    trace.log(
-        "if-cond",
-        &format!("{} {:?} ValueId({})", if_var, if_op, if_value_val.0)
-    );
-
    // Step 3: Extract then-branch update (e.g., sum = sum + 1 → var="sum", addend=<expr>)
    // Phase 256.7: update_addend is now ASTNode (supports variables like separator)
    let (update_var, update_addend_ast) = extract_then_update(if_stmt)?;
@ -182,6 +172,21 @@ pub fn lower_if_sum_pattern(
    }
    let cond_env = &local_cond_env; // Shadow the original cond_env

+    // Step 2: Extract if condition info (e.g., i > 0 → var="i", op=Gt, value=ValueId)
+    //
+    // IMPORTANT (Phase 283 P0): Extract using the local_cond_env.
+    // The pre-loop extraction phase runs before `i_param`/`sum_param` exist, so
+    // `i % 2 == 1` would resolve `i` via the caller's ConditionEnv and produce
+    // JoinIR ValueIds that the boundary cannot remap → undefined ValueId in MIR.
+    //
+    // By extracting here, Variable("i") resolves to `i_param` and remains remappable.
+    let (if_var, if_op, if_lhs_val, if_value_val, if_value_insts) =
+        extract_if_condition(if_stmt, &mut alloc_value, cond_env)?;
+    trace.log(
+        "if-cond",
+        &format!("{} {:?} ValueId({})", if_var, if_op, if_value_val.0)
+    );
+
    // === main() function ===
    let mut main_func = JoinFunction::new(main_id, "main".to_string(), main_params.clone());