fix(joinir): Phase 118 Pattern3 exit carrier PHI SSOT

src/mir/join_ir/lowering/loop_with_if_phi_if_sum.rs

@@ -127,13 +127,11 @@ pub fn lower_if_sum_pattern(
     // main() locals
     let i_init_val = alloc_value(); // i = 0
     let sum_init_val = alloc_value(); // sum = 0
-    let count_init_val = alloc_value(); // count = 0 (optional)
     let loop_result = alloc_value(); // result from loop_step
 
     // loop_step params
     let i_param = alloc_value();
     let sum_param = alloc_value();
-    let count_param = alloc_value();
 
     // loop_step locals
     // Phase 220-D: loop_limit_val and if_value_val are already allocated by extract_*_condition()
@@ -142,19 +140,14 @@ pub fn lower_if_sum_pattern(
     let exit_cond = alloc_value(); // negated loop condition
     let if_cmp = alloc_value(); // if condition comparison
     let sum_then = alloc_value(); // sum + update_addend
-    let count_const = alloc_value(); // count increment (1)
-    let count_then = alloc_value(); // count + 1
     let const_0 = alloc_value(); // 0 for else branch
     let sum_else = alloc_value(); // sum + 0 (identity)
-    let count_else = alloc_value(); // count + 0 (identity)
     let sum_new = alloc_value(); // Select result for sum
-    let count_new = alloc_value(); // Select result for count
     let step_const = alloc_value(); // counter step
     let i_next = alloc_value(); // i + step
 
     // k_exit params
     let sum_final = alloc_value();
-    let count_final = alloc_value();
 
     // === main() function ===
     let mut main_func = JoinFunction::new(main_id, "main".to_string(), vec![]);
@@ -171,16 +164,10 @@ pub fn lower_if_sum_pattern(
         value: ConstValue::Integer(0),
     }));
 
-    // count_init = 0
-    main_func.body.push(JoinInst::Compute(MirLikeInst::Const {
-        dst: count_init_val,
-        value: ConstValue::Integer(0),
-    }));
-
-    // result = loop_step(i_init, sum_init, count_init)
+    // result = loop_step(i_init, sum_init)
     main_func.body.push(JoinInst::Call {
         func: loop_step_id,
-        args: vec![i_init_val, sum_init_val, count_init_val],
+        args: vec![i_init_val, sum_init_val],
         k_next: None,
         dst: Some(loop_result),
     });
@@ -191,11 +178,11 @@ pub fn lower_if_sum_pattern(
 
     join_module.add_function(main_func);
 
-    // === loop_step(i, sum, count) function ===
+    // === loop_step(i, sum) function ===
     let mut loop_step_func = JoinFunction::new(
         loop_step_id,
         "loop_step".to_string(),
-        vec![i_param, sum_param, count_param],
+        vec![i_param, sum_param],
     );
 
     // --- Exit Condition Check ---
@@ -230,7 +217,7 @@ pub fn lower_if_sum_pattern(
     // Jump to exit if condition is false
     loop_step_func.body.push(JoinInst::Jump {
         cont: k_exit_id.as_cont(),
-        args: vec![sum_param, count_param],
+        args: vec![sum_param],
         cond: Some(exit_cond),
     });
 
@@ -270,22 +257,6 @@ pub fn lower_if_sum_pattern(
             rhs: const_0,
         }));
 
-    // count_then = count + 1
-    loop_step_func
-        .body
-        .push(JoinInst::Compute(MirLikeInst::Const {
-            dst: count_const,
-            value: ConstValue::Integer(1),
-        }));
-    loop_step_func
-        .body
-        .push(JoinInst::Compute(MirLikeInst::BinOp {
-            dst: count_then,
-            op: BinOpKind::Add,
-            lhs: count_param,
-            rhs: count_const,
-        }));
-
     // --- Else Branch ---
     // sum_else = sum + 0 (identity)
     loop_step_func
@@ -303,16 +274,6 @@ pub fn lower_if_sum_pattern(
             rhs: step_const,
         }));
 
-    // count_else = count + 0 (identity)
-    loop_step_func
-        .body
-        .push(JoinInst::Compute(MirLikeInst::BinOp {
-            dst: count_else,
-            op: BinOpKind::Add,
-            lhs: count_param,
-            rhs: step_const, // 0
-        }));
-
     // --- Select ---
     loop_step_func
         .body
@@ -323,15 +284,6 @@ pub fn lower_if_sum_pattern(
             else_val: sum_else,
         }));
 
-    loop_step_func
-        .body
-        .push(JoinInst::Compute(MirLikeInst::Select {
-            dst: count_new,
-            cond: if_cmp,
-            then_val: count_then,
-            else_val: count_else,
-        }));
-
     // --- Counter Update ---
     let step_const2 = alloc_value();
     loop_step_func
@@ -352,19 +304,15 @@ pub fn lower_if_sum_pattern(
     // --- Tail Recursion ---
     loop_step_func.body.push(JoinInst::Call {
         func: loop_step_id,
-        args: vec![i_next, sum_new, count_new],
+        args: vec![i_next, sum_new],
         k_next: None,
         dst: None,
     });
 
     join_module.add_function(loop_step_func);
 
-    // === k_exit(sum_final, count_final) function ===
-    let mut k_exit_func = JoinFunction::new(
-        k_exit_id,
-        "k_exit".to_string(),
-        vec![sum_final, count_final],
-    );
+    // === k_exit(sum_final) function ===
+    let mut k_exit_func = JoinFunction::new(k_exit_id, "k_exit".to_string(), vec![sum_final]);
 
     k_exit_func.body.push(JoinInst::Ret {
         value: Some(sum_final),
@@ -374,9 +322,9 @@ pub fn lower_if_sum_pattern(
     join_module.entry = Some(main_id);
 
     // Build ExitMeta
+    // SSOT: use the accumulator name extracted from AST (no hardcoded carrier names).
     let mut exit_values = vec![];
-    exit_values.push(("sum".to_string(), sum_final));
-    exit_values.push(("count".to_string(), count_final));
+    exit_values.push((update_var.clone(), sum_final));
 
     let exit_meta = ExitMeta::multiple(exit_values);