refactor(mir): phase260 p0 edge-args plumbing (strangler) + ssot api + docs

src/mir/optimizer.rs

@@ -524,7 +524,7 @@ mod tests {
     }
 
     #[test]
-    fn test_dce_keeps_jump_args_values() {
+    fn test_dce_keeps_edge_args_values() {
         let signature = FunctionSignature {
             name: "main".to_string(),
             params: vec![],
@@ -533,6 +533,7 @@ mod tests {
         };
         let mut func = MirFunction::new(signature, BasicBlockId::new(0));
         let bb0 = BasicBlockId::new(0);
+        let bb1 = BasicBlockId::new(1);
         let mut b0 = BasicBlock::new(bb0);
         let v0 = ValueId::new(0);
         let v1 = ValueId::new(1);
@@ -541,9 +542,17 @@ mod tests {
             value: ConstValue::Integer(1),
         });
         b0.add_instruction(MirInstruction::Copy { dst: v1, src: v0 });
-        b0.add_instruction(MirInstruction::Return { value: None });
-        b0.jump_args = Some(vec![v1]);
+        b0.set_jump_with_edge_args(
+            bb1,
+            Some(crate::mir::EdgeArgs {
+                layout: crate::mir::join_ir::lowering::inline_boundary::JumpArgsLayout::CarriersOnly,
+                values: vec![v1],
+            }),
+        );
         func.add_block(b0);
+        let mut exit_block = BasicBlock::new(bb1);
+        exit_block.set_terminator(MirInstruction::Return { value: None });
+        func.add_block(exit_block);
         let mut module = MirModule::new("test".to_string());
         module.add_function(func);
 
@@ -555,7 +564,7 @@ mod tests {
             .instructions
             .iter()
             .any(|inst| matches!(inst, MirInstruction::Copy { .. }));
-        assert!(has_copy, "Copy used only by jump_args should not be eliminated");
+        assert!(has_copy, "Copy used only by edge args should not be eliminated");
     }
 
     #[test]