Merge branch 'develop' of github.com:Champii/Rock

src/lib/ast/tree.rs

@@ -468,11 +468,21 @@ impl Expression {
         }
     }
 
+    #[allow(dead_code)]
+    pub fn is_return(&self) -> bool {
+        matches!(&self, Expression::Return(_))
+    }
+
     #[allow(dead_code)]
     pub fn new_unary(unary: UnaryExpr) -> Expression {
         Expression::UnaryExpr(unary)
     }
 
+    #[allow(dead_code)]
+    pub fn new_return(expr: Expression) -> Expression {
+        Expression::Return(Box::new(expr))
+    }
+
     #[allow(dead_code)]
     pub fn new_binop(unary: UnaryExpr, operator: Operator, expr: Expression) -> Expression {
         Expression::BinopExpr(unary, operator, Box::new(expr))

src/lib/codegen/codegen_context.rs

@@ -322,9 +322,17 @@ impl<'a> CodegenContext<'a> {
 
         builder.position_at_end(basic_block);
 
-        let stmt = body
+        let first_return_idx = body
             .stmts
             .iter()
+            .position(|s| s.is_return())
+            .unwrap_or(body.stmts.len());
+
+        let stmts = body.stmts.iter().take(first_return_idx + 1);
+
+        // FIXME: Add warning here for unreachable statements
+
+        let stmt = stmts
             .map(|stmt| self.lower_stmt(stmt, builder))
             .last()
             .unwrap()?;
@@ -545,7 +553,8 @@ impl<'a> CodegenContext<'a> {
             ExpressionKind::Return(expr) => {
                 let val = self.lower_expression(expr, builder)?;
 
-                builder.build_return(Some(&val.as_basic_value_enum()));
+                // This is disabled because this is handled in lower_body
+                // builder.build_return(Some(&val.as_basic_value_enum()));
 
                 val
             }

src/lib/hir/tree.rs

@@ -337,6 +337,13 @@ impl Statement {
             StatementKind::For(f) => f.get_hir_id(),
         }
     }
+
+    pub fn is_return(&self) -> bool {
+        match &*self.kind {
+            StatementKind::Expression(expr) => expr.is_return(),
+            _ => false,
+        }
+    }
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -516,6 +523,14 @@ impl Expression {
             panic!("Not a literal");
         }
     }
+
+    pub fn is_return(&self) -> bool {
+        if let ExpressionKind::Return(_) = &*self.kind {
+            true
+        } else {
+            false
+        }
+    }
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]

src/lib/parser/mod.rs

@@ -668,6 +668,10 @@ pub fn parse_assign_left_side(input: Parser) -> Res<Parser, AssignLeftSide> {
 
 pub fn parse_expression(input: Parser) -> Res<Parser, Expression> {
     alt((
+        map(
+            preceded(terminated(tag("return"), space1), parse_expression),
+            Expression::new_return,
+        ),
         map(
             tuple((
                 parse_unary,
@@ -681,7 +685,6 @@ pub fn parse_expression(input: Parser) -> Res<Parser, Expression> {
         map(parse_native_operator, |(op, id1, id2)| {
             Expression::new_native_operator(op, id1, id2)
         }),
-        // TODO: Return
     ))(input)
 }
 

src/lib/testcases/basic/early_return/main.rk

@@ -0,0 +1,4 @@
+main =
+  let a = 42
+  return a
+  28

src/lib/testcases/basic/early_return/main.rk.out

@@ -0,0 +1 @@
+42

src/lib/tests.rs

@@ -106,6 +106,10 @@ fn testcases_basic_simple_struct_main() {
     run("testcases/basic/simple_struct/main.rk", include_str!("testcases/basic/simple_struct/main.rk"), include_str!("testcases/basic/simple_struct/main.rk.out"), include_str!("testcases/basic/simple_struct/main.rk.stdout"));
 }
 #[test]
+fn testcases_basic_early_return_main() {
+    run("testcases/basic/early_return/main.rk", include_str!("testcases/basic/early_return/main.rk"), include_str!("testcases/basic/early_return/main.rk.out"), include_str!("testcases/basic/early_return/main.rk.stdout"));
+}
+#[test]
 fn testcases_basic_bool_false_main() {
     run("testcases/basic/bool_false/main.rk", include_str!("testcases/basic/bool_false/main.rk"), include_str!("testcases/basic/bool_false/main.rk.out"), include_str!("testcases/basic/bool_false/main.rk.stdout"));
 }