[Not Working] Implement function call with no args

9cc.h

@@ -72,6 +72,7 @@ typedef enum {
   ND_RETURN, // return
   ND_IF,     // if
   ND_FOR,    // for | while
+  ND_FUNCALL,// function call
 } NodeKind;
 
 typedef struct Node Node;
@@ -93,7 +94,8 @@ struct Node {
   // kind == ND_STMT
   Node *body; // statementの内容
   Node *next; // next statement
-
+  // kind == ND_FUNCALL
+  char *func_name;
 };
 
 Node stmt_head; // stmtのリストの先頭(ダミーノード)

README.md

@@ -8,8 +8,7 @@ C言語(のサブセット)コンパイラ
 - `return` statement
 - `if` `else` statement
 - `while` `for` statement
-
-
+- `{…}` compound statements (blocks)
 
 ## BNF
 ```
@@ -27,5 +26,5 @@ relational = add ("<" add | "<=" add | ">" add | ">=" add)*
 add        = mul ("+" mul | "-" mul)*
 mul        = unary ("*" unary | "/" unary)*
 unary      = ("+" | "-")? primary
-primary    = num | ident | "(" expr ")"
+primary    = num | ident ("(" ")")? | "(" expr ")"
 ```

codegen.c

@@ -101,6 +101,9 @@ void gen(Node *node) {
       printf(".L.end.%d:\n", label);
       return;
     }
+    case ND_FUNCALL:
+      printf("  call %s\n", node->func_name);
+      return;
   }
 
   gen(node->lhs);

parse.c

@@ -47,13 +47,32 @@ int expect_number() {
   return val;
 }
 
-Lvar *find_lvar() {
+Lvar *find_lvar(Token *tok) {
   for (Lvar *var = locals; var != NULL; var = var->next)
-    if (var->len == token->len && !memcmp(token->start, var->name, var->len))
+    if (var->len == tok->len && !memcmp(tok->start, var->name, var->len))
       return var;
   return NULL;
 }
 
+Node *new_lvar_node(Token *tok) {
+  Node *node = new_node(ND_LVAR);
+  Lvar *lvar = find_lvar(tok);
+
+  if (lvar != NULL) {
+    node->offset = lvar->offset;
+  } else { // 初登場のローカル変数の場合、localsの先頭に繋ぐ
+    lvar = calloc(1, sizeof(Lvar));
+    lvar->len = tok->len;
+    lvar->offset = locals->offset + 8;
+    lvar->name = tok->start;
+    lvar->next = locals;
+    locals = lvar;
+
+    node->offset = lvar->offset;
+  }
+  return node;
+}
+
 void init_locals() {
   tail.offset = 0;
   tail.next = NULL;
@@ -234,25 +253,24 @@ Node *primary() {
     expect(")");
     return node;
   }
-  else if (token->kind == TK_IDENT) { // ローカル変数の場合
-    Node *node = new_node(ND_LVAR);
-    Lvar *lvar = find_lvar();
-
-    if (lvar != NULL) {
-      node->offset = lvar->offset;
-    } else { // 初登場のローカル変数の場合、localsの先頭に繋ぐ
-      lvar = calloc(1, sizeof(Lvar));
-      lvar->len = token->len;
-      lvar->offset = locals->offset + 8;
-      lvar->name = token->start;
-      lvar->next = locals;
-      locals = lvar;
-
-      node->offset = lvar->offset;
-    }
+
+  else if (token->kind == TK_IDENT) {
+    Node *node;
+    Token *tok = token;
     token = token->next;
+    if (consume(TK_RESERVED, "(")) { // 関数呼び出しの場合
+      // 今後ここに引数のparse処理が入るはず
+      expect(")");
+      node = new_node(ND_FUNCALL);
+      node->func_name = calloc(tok->len, sizeof(char));
+      memcpy(node->func_name, tok->start, tok->len);
+    }
+    else { // ローカル変数の場合
+      node = new_lvar_node(tok);
+    }
     return node;
   }
+
   else
     return new_num(expect_number()); // それ以外は整数のはず
 }

test.c

@@ -0,0 +1,3 @@
+int foo() {
+  return 5;
+}

test.sh

@@ -99,4 +99,6 @@ assert 10 'a=3; {b=7; if(a==3) return a+b;}'
 
 assert 3 'a=3; if(a==1) return 1; if(a==2) return 2; if(a==3) return 3;'
 
+assert 5 'return foo();'
+
 echo OK