disallow return statements in rules' bodies

Author: nunoplopes

rule-preprocessor/src/syntactic.rs

@@ -391,15 +391,8 @@ impl<'a> FnIrBuilder<'a> {
                                 }
                             Some(Access::Unknown)
                         },
-                        ast::ReturnExpr(ret) => {
-                            if self.returns_mut_ref()
-                                && ret.expr().is_some_and(|e|
-                                    e.syntax().text_range() == name_ref.syntax().text_range())
-                            {
-                                Some(Access::Write)
-                            } else {
-                                Some(Access::Read)
-                            }
+                        ast::ReturnExpr(_) => {
+                            panic!("return statements are not supported in rule bodies");
                         },
                         ast::StmtList(sl) => {
                             if self.returns_mut_ref()

rules/algorithm/ir_refcount.json

@@ -98,7 +98,7 @@
         }
       },
       {
-        "text": ";\n    if count <= 1 {\n        return "
+        "text": ";\n    if count <= 1 {\n        "
       },
       {
         "placeholder": {
@@ -107,7 +107,7 @@
         }
       },
       {
-        "text": ";\n    }\n\n    let mut write_ptr = "
+        "text": "\n    } else {\n        let mut write_ptr = "
       },
       {
         "method_call": {
@@ -127,7 +127,7 @@
         }
       },
       {
-        "text": ";\n    let mut iter = PtrValueIter::new("
+        "text": ";\n        let mut iter = PtrValueIter::new("
       },
       {
         "placeholder": {
@@ -136,7 +136,7 @@
         }
       },
       {
-        "text": ", count);\n    let mut last_unique = "
+        "text": ", count);\n        let mut last_unique = "
       },
       {
         "method_call": {
@@ -164,7 +164,7 @@
         }
       },
       {
-        "text": ";\n\n    // the first unique value is already in place\n    write_ptr += 1;\n\n    for current_val in iter {\n        if current_val != last_unique {\n            "
+        "text": ";\n\n        // the first unique value is already in place\n        write_ptr += 1;\n\n        for current_val in iter {\n            if current_val != last_unique {\n                "
       },
       {
         "method_call": {
@@ -198,7 +198,7 @@
         }
       },
       {
-        "text": ";\n            last_unique = current_val;\n            write_ptr += 1;\n        }\n    }\n    write_ptr"
+        "text": ";\n                last_unique = current_val;\n                write_ptr += 1;\n            }\n        }\n        write_ptr\n    }"
       }
     ],
     "generics": {

rules/algorithm/tgt_refcount.rs

@@ -73,24 +73,24 @@ fn f9<T1: Clone + ByteRepr>(a0: Ptr<T1>, a1: Ptr<T1>) {
 fn f10<T1: PartialEq + Clone + ByteRepr>(a0: Ptr<T1>, a1: Ptr<T1>) -> Ptr<T1> {
     let count = a1.get_offset() - a0.get_offset();
     if count <= 1 {
-        return a1;
-    }
-
-    let mut write_ptr = a0.clone();
-    let mut iter = PtrValueIter::new(a0, count);
-    let mut last_unique = iter.next().unwrap();
-
-    // the first unique value is already in place
-    write_ptr += 1;
-
-    for current_val in iter {
-        if current_val != last_unique {
-            write_ptr.write(current_val.clone());
-            last_unique = current_val;
-            write_ptr += 1;
+        a1
+    } else {
+        let mut write_ptr = a0.clone();
+        let mut iter = PtrValueIter::new(a0, count);
+        let mut last_unique = iter.next().unwrap();
+
+        // the first unique value is already in place
+        write_ptr += 1;
+
+        for current_val in iter {
+            if current_val != last_unique {
+                write_ptr.write(current_val.clone());
+                last_unique = current_val;
+                write_ptr += 1;
+            }
         }
+        write_ptr
     }
-    write_ptr
 }
 
 fn f12<T1: Clone + ByteRepr>(a0: Ptr<T1>, a1: Ptr<T1>, a2: T1) {

tests/unit/out/unsafe/libc_struct_without_default.rs

@@ -16,7 +16,7 @@ impl Default for UserDefined {
     fn default() -> Self {
         UserDefined {
             a: std::array::from_fn::<_, 1, _>(|_| Default::default()).to_vec(),
-            v: <Vec<i32>>::default(),
+            v: Default::default(),
         }
     }
 }