parser: Create the literal node type

Since we want to extend our code to support multiple kind of expression
it does not make sense that the return statement always return a number.

For now on, return statement has an ast_node_t as argument, meaning that
it could be anything. The literal_node_t was also implemented in order
to keep the application behavior.

Following the C's calling convention the literal values are stored at
%eax and the return takes this argument to do anything it is needed.

Signed-off-by: Carlos Maniero <carlosmaniero@gmail.com>
Reviewed-by: Johnny Richard <johnny@johnnyrichard.com>

1 files changed, 24 insertions, 2 deletions

diff --git a/src/ast.c b/src/ast.c
index 50f6a2e..7f3af9e 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -39,6 +39,12 @@ ast_node_return_stmt_accept_visitor(ast_node_t *node, ast_visitor_t *visitor)
   visitor->visit_return_stmt(visitor, &node->data.return_stmt);
 }
 
+static void
+ast_node_literal_visitor(ast_node_t *node, ast_visitor_t *visitor)
+{
+  visitor->visit_literal(visitor, &node->data.literal);
+}
+
 ast_node_t*
 ast_node_new()
 {
@@ -62,6 +68,8 @@ ast_node_destroy(ast_node_t *node)
       break;
     case AST_UNKOWN_NODE:
       break;
+    case AST_LITERAL:
+      break;
     default:
       assert(false && "unmapped free strategy");
   }
@@ -69,13 +77,13 @@ ast_node_destroy(ast_node_t *node)
 }
 
 void
-ast_node_init_return_stmt(ast_node_t *node, uint32_t number)
+ast_node_init_return_stmt(ast_node_t *node, ast_node_t *argument)
 {
   node->accept_visitor = &ast_node_return_stmt_accept_visitor,
   node->kind = AST_RETURN_STMT;
   node->data = (ast_node_data_t) {
     .return_stmt = {
-      .number = number
+      .argument = argument
     }
   };
 }
@@ -94,3 +102,17 @@ ast_node_init_function_declaration(ast_node_t *node, string_view_t name, type_t
   };
 }
 
+void
+ast_literal_integer_create(ast_node_t *node, uint32_t number)
+{
+  node->accept_visitor = &ast_node_literal_visitor;
+  node->kind = AST_LITERAL;
+  node->data = (ast_node_data_t) {
+    .literal = {
+      .kind = AST_LITERAL_INTEGER,
+      .value = {
+        .integer = number
+      }
+    }
+  };
+}