feat: implement parsing of "sizeof expr"

2 files changed, 31 insertions, 19 deletions

diff --git a/src/parse.c b/src/parse.c
index 12e8815..80007ed 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -766,26 +766,15 @@ static AstNode* parse_unary_expr(Parser* p) {
         AstNode* operand = parse_unary_expr(p);
         return ast_new_assign_sub_expr(operand, ast_new_int(1));
     } else if (consume_token_if(p, TokenKind_keyword_sizeof)) {
-        expect(p, TokenKind_paren_l);
-        Token* next_tok = peek_token(p);
-        Type* ty = NULL;
-        if (next_tok->kind == TokenKind_ident) {
-            int lvar_idx = find_lvar(p, next_tok->value.string);
-            if (lvar_idx != -1) {
-                next_token(p);
-                ty = p->lvars.data[lvar_idx].ty;
-            }
-            int gvar_idx = find_gvar(p, next_tok->value.string);
-            if (gvar_idx != -1) {
-                next_token(p);
-                ty = p->gvars.data[gvar_idx].ty;
-            }
-        }
-        if (!ty) {
-            ty = parse_type_name(p);
+        if (peek_token(p)->kind == TokenKind_paren_l && is_type_token(p, peek_token2(p))) {
+            next_token(p);
+            Type* ty = parse_type_name(p);
+            expect(p, TokenKind_paren_r);
+            return ast_new_int(type_sizeof(ty));
+        } else {
+            AstNode* expr = parse_unary_expr(p);
+            return ast_new_int(type_sizeof(expr->ty));
         }
-        expect(p, TokenKind_paren_r);
-        return ast_new_int(type_sizeof(ty));
     }
     return parse_postfix_expr(p);
 }
diff --git a/tests/operators.c b/tests/operators.c
index 9e9ba08..e089477 100644
--- a/tests/operators.c
+++ b/tests/operators.c
@@ -119,4 +119,27 @@ int main() {
     // ternary operator
     ASSERT_EQ(2, 1 ? 2 : 3);
     ASSERT_EQ(5, 0 ? 4 : 5);
+
+    // sizeof operator
+    // sizeof '(' type-name ')'
+    ASSERT_EQ(4, sizeof(int));
+    ASSERT_EQ(1, sizeof(char));
+
+    // sizeof unary-expr (with parenthesized expressions)
+    ASSERT_EQ(4, sizeof(+123));
+    ASSERT_EQ(4, sizeof(-1));
+    ASSERT_EQ(4, sizeof(1 + 2));
+    ASSERT_EQ(4, sizeof(~0));
+    ASSERT_EQ(4, sizeof(!0));
+
+    // sizeof unary-expr (variable)
+    int sz_var = 42;
+    ASSERT_EQ(4, sizeof(sz_var));
+    ASSERT_EQ(4, sizeof sz_var);
+
+    // sizeof with more complex expressions
+    char sz_c = 'a';
+    ASSERT_EQ(1, sizeof sz_c);
+    ASSERT_EQ(1, sizeof(sz_c));
+    ASSERT_EQ(4, sizeof(sz_c + 1));
 }