feat: separate main.c

1 files changed, 1009 insertions, 0 deletions

diff --git a/parse.c b/parse.c
new file mode 100644
index 0000000..b056077
--- /dev/null
+++ b/parse.c
@@ -0,0 +1,1009 @@
+#define LVAR_MAX 32
+
+struct LocalVar {
+    String name;
+    Type* ty;
+};
+typedef struct LocalVar LocalVar;
+
+struct GlobalVar {
+    String name;
+    Type* ty;
+};
+typedef struct GlobalVar GlobalVar;
+
+struct Func {
+    String name;
+    Type* ty;
+};
+typedef struct Func Func;
+
+struct Parser {
+    Token* tokens;
+    int pos;
+    LocalVar* lvars;
+    int n_lvars;
+    GlobalVar* gvars;
+    int n_gvars;
+    Func* funcs;
+    int n_funcs;
+    AstNode* structs;
+    int n_structs;
+    AstNode* enums;
+    int n_enums;
+    AstNode* typedefs;
+    int n_typedefs;
+    char** str_literals;
+    int n_str_literals;
+};
+typedef struct Parser Parser;
+
+Parser* parser_new(Token* tokens) {
+    Parser* p = calloc(1, sizeof(Parser));
+    p->tokens = tokens;
+    p->gvars = calloc(128, sizeof(GlobalVar));
+    p->funcs = calloc(256, sizeof(Func));
+    p->structs = calloc(64, sizeof(AstNode));
+    p->enums = calloc(16, sizeof(AstNode));
+    p->typedefs = calloc(64, sizeof(AstNode));
+    p->str_literals = calloc(1024, sizeof(char*));
+    return p;
+}
+
+Token* peek_token(Parser* p) {
+    return p->tokens + p->pos;
+}
+
+Token* next_token(Parser* p) {
+    ++p->pos;
+    return p->tokens + p->pos - 1;
+}
+
+int eof(Parser* p) {
+    return peek_token(p)->kind != TokenKind_eof;
+}
+
+Token* expect(Parser* p, int expected) {
+    Token* t = next_token(p);
+    if (t->kind == expected) {
+        return t;
+    }
+
+    char* buf = calloc(1024, sizeof(char));
+    sprintf(buf, "expected '%s', but got '%s'", token_kind_stringify(expected), token_stringify(t));
+    fatal_error(buf);
+}
+
+int find_lvar(Parser* p, const String* name) {
+    int i;
+    for (i = 0; i < p->n_lvars; ++i) {
+        if (string_equals(&p->lvars[i].name, name)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+int find_gvar(Parser* p, const String* name) {
+    int i;
+    for (i = 0; i < p->n_gvars; ++i) {
+        if (string_equals(&p->gvars[i].name, name)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+int find_func(Parser* p, const String* name) {
+    int i;
+    for (i = 0; i < p->n_funcs; ++i) {
+        if (string_equals(&p->funcs[i].name, name)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+int find_struct(Parser* p, const String* name) {
+    int i;
+    for (i = 0; i < p->n_structs; ++i) {
+        if (string_equals(&p->structs[i].name, name)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+int find_enum(Parser* p, const String* name) {
+    int i;
+    for (i = 0; i < p->n_enums; ++i) {
+        if (string_equals(&p->enums[i].name, name)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+int find_enum_member(Parser* p, const String* name) {
+    int i;
+    int j;
+    for (i = 0; i < p->n_enums; ++i) {
+        for (j = 0; j < p->enums[i].node_members->node_len; ++j) {
+            if (string_equals(&p->enums[i].node_members->node_items[j].name, name)) {
+                return i * 1000 + j;
+            }
+        }
+    }
+    return -1;
+}
+
+int find_typedef(Parser* p, const String* name) {
+    int i;
+    for (i = 0; i < p->n_typedefs; ++i) {
+        if (string_equals(&p->typedefs[i].name, name)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+AstNode* parse_expr(Parser* p);
+AstNode* parse_stmt(Parser* p);
+
+String* parse_ident(Parser* p) {
+    return &expect(p, TokenKind_ident)->raw;
+}
+
+int register_str_literal(Parser* p, char* s) {
+    p->str_literals[p->n_str_literals] = s;
+    ++p->n_str_literals;
+    return p->n_str_literals;
+}
+
+AstNode* parse_primary_expr(Parser* p) {
+    Token* t = next_token(p);
+    AstNode* e;
+    char* buf;
+    if (t->kind == TokenKind_literal_int) {
+        return ast_new_int(atoi(string_to_cstr(&t->raw)));
+    } else if (t->kind == TokenKind_literal_str) {
+        e = ast_new(AstNodeKind_str_expr);
+        e->node_idx = register_str_literal(p, string_to_cstr(&t->raw));
+        return e;
+    } else if (t->kind == TokenKind_paren_l) {
+        e = parse_expr(p);
+        expect(p, TokenKind_paren_r);
+        return e;
+    } else if (t->kind == TokenKind_ident) {
+        String* name = &t->raw;
+
+        if (peek_token(p)->kind == TokenKind_paren_l) {
+            e = ast_new(AstNodeKind_func_call);
+            int func_idx = find_func(p, name);
+            if (func_idx == -1) {
+                buf = calloc(1024, sizeof(char));
+                sprintf(buf, "undefined function: %.*s", name->len, name->data);
+                fatal_error(buf);
+            }
+            e->name.data = name->data;
+            e->name.len = name->len;
+            e->ty = p->funcs[func_idx].ty;
+            return e;
+        }
+
+        int lvar_idx = find_lvar(p, name);
+        if (lvar_idx == -1) {
+            int gvar_idx = find_gvar(p, name);
+            if (gvar_idx == -1) {
+                int enum_member_idx = find_enum_member(p, name);
+                if (enum_member_idx == -1) {
+                    buf = calloc(1024, sizeof(char));
+                    sprintf(buf, "undefined variable: %.*s", name->len, name->data);
+                    fatal_error(buf);
+                }
+                int enum_idx = enum_member_idx / 1000;
+                int n = enum_member_idx % 1000;
+                e = ast_new_int(p->enums[enum_idx].node_members->node_items[n].node_int_value);
+                e->ty = type_new(TypeKind_enum);
+                e->ty->def = p->enums + enum_idx;
+                return e;
+            }
+            e = ast_new(AstNodeKind_gvar);
+            e->name.data = name->data;
+            e->name.len = name->len;
+            e->ty = p->gvars[gvar_idx].ty;
+            return e;
+        }
+
+        e = ast_new(AstNodeKind_lvar);
+        e->name.data = name->data;
+        e->name.len = name->len;
+        e->node_idx = lvar_idx;
+        e->ty = p->lvars[lvar_idx].ty;
+        return e;
+    } else {
+        buf = calloc(1024, sizeof(char));
+        sprintf(buf, "expected primary expression, but got '%s'", token_stringify(t));
+        fatal_error(buf);
+    }
+}
+
+AstNode* parse_arg_list(Parser* p) {
+    AstNode* list = ast_new_list(6);
+    while (peek_token(p)->kind != TokenKind_paren_r) {
+        AstNode* arg = parse_expr(p);
+        ast_append(list, arg);
+        if (peek_token(p)->kind == TokenKind_comma) {
+            next_token(p);
+        } else {
+            break;
+        }
+    }
+    if (list->node_len > 6) {
+        fatal_error("too many arguments");
+    }
+    return list;
+}
+
+AstNode* parse_postfix_expr(Parser* p) {
+    AstNode* ret = parse_primary_expr(p);
+    String* name;
+    while (1) {
+        TokenKind tk = peek_token(p)->kind;
+        if (tk == TokenKind_paren_l) {
+            next_token(p);
+            AstNode* args = parse_arg_list(p);
+            expect(p, TokenKind_paren_r);
+            ret->node_args = args;
+        } else if (tk == TokenKind_bracket_l) {
+            next_token(p);
+            AstNode* idx = parse_expr(p);
+            expect(p, TokenKind_bracket_r);
+            idx = ast_new_binary_expr(TokenKind_star, idx, ast_new_int(type_sizeof(ret->ty->to)));
+            ret = ast_new_deref_expr(ast_new_binary_expr(TokenKind_plus, ret, idx));
+        } else if (tk == TokenKind_dot) {
+            next_token(p);
+            name = parse_ident(p);
+            ret = ast_new_member_access_expr(ast_new_ref_expr(ret), name);
+        } else if (tk == TokenKind_arrow) {
+            next_token(p);
+            name = parse_ident(p);
+            ret = ast_new_member_access_expr(ret, name);
+        } else {
+            break;
+        }
+    }
+    return ret;
+}
+
+int is_type_token(Parser* p, Token* token) {
+    if (token->kind == TokenKind_keyword_int || token->kind == TokenKind_keyword_long ||
+        token->kind == TokenKind_keyword_char || token->kind == TokenKind_keyword_void ||
+        token->kind == TokenKind_keyword_enum || token->kind == TokenKind_keyword_struct ||
+        token->kind == TokenKind_keyword_const) {
+        return 1;
+    }
+    if (token->kind != TokenKind_ident) {
+        return 0;
+    }
+    return find_typedef(p, &token->raw) != -1;
+}
+
+Type* parse_type(Parser* p) {
+    Token* t = next_token(p);
+    char* buf;
+    String* name;
+    if (t->kind == TokenKind_keyword_const) {
+        t = next_token(p);
+    }
+    if (!is_type_token(p, t)) {
+        buf = calloc(1024, sizeof(char));
+        sprintf(buf, "parse_type: expected type, but got '%s'", token_stringify(t));
+        fatal_error(buf);
+    }
+    Type* ty;
+    if (t->kind == TokenKind_ident) {
+        int typedef_idx = find_typedef(p, &t->raw);
+        if (typedef_idx == -1) {
+            buf = calloc(1024, sizeof(char));
+            sprintf(buf, "parse_type: unknown typedef, %.*s", t->raw.len, t->raw.data);
+            fatal_error(buf);
+        }
+        ty = p->typedefs[typedef_idx].ty;
+    } else {
+        ty = type_new(TypeKind_unknown);
+        if (t->kind == TokenKind_keyword_int) {
+            ty->kind = TypeKind_int;
+        } else if (t->kind == TokenKind_keyword_long) {
+            ty->kind = TypeKind_long;
+        } else if (t->kind == TokenKind_keyword_char) {
+            ty->kind = TypeKind_char;
+        } else if (t->kind == TokenKind_keyword_void) {
+            ty->kind = TypeKind_void;
+        } else if (t->kind == TokenKind_keyword_enum) {
+            ty->kind = TypeKind_enum;
+            name = parse_ident(p);
+            int enum_idx = find_enum(p, name);
+            if (enum_idx == -1) {
+                buf = calloc(1024, sizeof(char));
+                sprintf(buf, "parse_type: unknown enum, %.*s", name->len, name->data);
+                fatal_error(buf);
+            }
+            ty->def = p->enums + enum_idx;
+        } else if (t->kind == TokenKind_keyword_struct) {
+            ty->kind = TypeKind_struct;
+            name = parse_ident(p);
+            int struct_idx = find_struct(p, name);
+            if (struct_idx == -1) {
+                buf = calloc(1024, sizeof(char));
+                sprintf(buf, "parse_type: unknown struct, %.*s", name->len, name->data);
+                fatal_error(buf);
+            }
+            ty->def = p->structs + struct_idx;
+        } else {
+            unreachable();
+        }
+    }
+    while (1) {
+        if (peek_token(p)->kind == TokenKind_star) {
+            next_token(p);
+            ty = type_new_ptr(ty);
+        } else {
+            break;
+        }
+    }
+    return ty;
+}
+
+AstNode* parse_prefix_expr(Parser* p) {
+    AstNode* operand;
+    TokenKind op = peek_token(p)->kind;
+    if (op == TokenKind_minus) {
+        next_token(p);
+        operand = parse_prefix_expr(p);
+        return ast_new_binary_expr(op, ast_new_int(0), operand);
+    } else if (op == TokenKind_not) {
+        next_token(p);
+        operand = parse_prefix_expr(p);
+        return ast_new_unary_expr(op, operand);
+    } else if (op == TokenKind_and) {
+        next_token(p);
+        operand = parse_prefix_expr(p);
+        return ast_new_ref_expr(operand);
+    } else if (op == TokenKind_star) {
+        next_token(p);
+        operand = parse_prefix_expr(p);
+        return ast_new_deref_expr(operand);
+    } else if (op == TokenKind_plusplus) {
+        next_token(p);
+        operand = parse_prefix_expr(p);
+        return ast_new_assign_add_expr(operand, ast_new_int(1));
+    } else if (op == TokenKind_minusminus) {
+        next_token(p);
+        operand = parse_prefix_expr(p);
+        return ast_new_assign_sub_expr(operand, ast_new_int(1));
+    } else if (op == TokenKind_keyword_sizeof) {
+        next_token(p);
+        expect(p, TokenKind_paren_l);
+        Type* ty = parse_type(p);
+        expect(p, TokenKind_paren_r);
+        return ast_new_int(type_sizeof(ty));
+    }
+    return parse_postfix_expr(p);
+}
+
+AstNode* parse_multiplicative_expr(Parser* p) {
+    AstNode* lhs = parse_prefix_expr(p);
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_star || op == TokenKind_slash || op == TokenKind_percent) {
+            next_token(p);
+            AstNode* rhs = parse_prefix_expr(p);
+            lhs = ast_new_binary_expr(op, lhs, rhs);
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_additive_expr(Parser* p) {
+    AstNode* lhs = parse_multiplicative_expr(p);
+    AstNode* rhs;
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_plus) {
+            next_token(p);
+            rhs = parse_multiplicative_expr(p);
+            if (lhs->ty->kind == TypeKind_ptr) {
+                lhs = ast_new_binary_expr(
+                    op, lhs, ast_new_binary_expr(TokenKind_star, rhs, ast_new_int(type_sizeof(lhs->ty->to))));
+            } else if (rhs->ty->kind == TypeKind_ptr) {
+                lhs = ast_new_binary_expr(
+                    op, ast_new_binary_expr(TokenKind_star, lhs, ast_new_int(type_sizeof(rhs->ty->to))), rhs);
+            } else {
+                lhs = ast_new_binary_expr(op, lhs, rhs);
+            }
+        } else if (op == TokenKind_minus) {
+            next_token(p);
+            rhs = parse_multiplicative_expr(p);
+            if (lhs->ty->kind == TypeKind_ptr) {
+                if (rhs->ty->kind == TypeKind_ptr) {
+                    // (a - b) / sizeof(a)
+                    lhs = ast_new_binary_expr(TokenKind_slash, ast_new_binary_expr(op, lhs, rhs),
+                                              ast_new_int(type_sizeof(lhs->ty->to)));
+                } else {
+                    // a - b*sizeof(a)
+                    lhs = ast_new_binary_expr(
+                        op, lhs, ast_new_binary_expr(TokenKind_star, rhs, ast_new_int(type_sizeof(lhs->ty->to))));
+                }
+            } else {
+                lhs = ast_new_binary_expr(op, lhs, rhs);
+            }
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_relational_expr(Parser* p) {
+    AstNode* lhs = parse_additive_expr(p);
+    AstNode* rhs;
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_lt || op == TokenKind_le) {
+            next_token(p);
+            rhs = parse_additive_expr(p);
+            lhs = ast_new_binary_expr(op, lhs, rhs);
+        } else if (op == TokenKind_gt) {
+            next_token(p);
+            rhs = parse_additive_expr(p);
+            lhs = ast_new_binary_expr(TokenKind_lt, rhs, lhs);
+        } else if (op == TokenKind_ge) {
+            next_token(p);
+            rhs = parse_additive_expr(p);
+            lhs = ast_new_binary_expr(TokenKind_le, rhs, lhs);
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_equality_expr(Parser* p) {
+    AstNode* lhs = parse_relational_expr(p);
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_eq || op == TokenKind_ne) {
+            next_token(p);
+            AstNode* rhs = parse_relational_expr(p);
+            lhs = ast_new_binary_expr(op, lhs, rhs);
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_logical_and_expr(Parser* p) {
+    AstNode* lhs = parse_equality_expr(p);
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_andand) {
+            next_token(p);
+            AstNode* rhs = parse_equality_expr(p);
+            AstNode* e = ast_new(AstNodeKind_logical_expr);
+            e->node_op = op;
+            e->node_lhs = lhs;
+            e->node_rhs = rhs;
+            e->ty = type_new(TypeKind_int);
+            lhs = e;
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_logical_or_expr(Parser* p) {
+    AstNode* lhs = parse_logical_and_expr(p);
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_oror) {
+            next_token(p);
+            AstNode* rhs = parse_logical_and_expr(p);
+            AstNode* e = ast_new(AstNodeKind_logical_expr);
+            e->node_op = op;
+            e->node_lhs = lhs;
+            e->node_rhs = rhs;
+            e->ty = type_new(TypeKind_int);
+            lhs = e;
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_assignment_expr(Parser* p) {
+    AstNode* lhs = parse_logical_or_expr(p);
+    AstNode* rhs;
+    while (1) {
+        TokenKind op = peek_token(p)->kind;
+        if (op == TokenKind_assign) {
+            next_token(p);
+            rhs = parse_logical_or_expr(p);
+            lhs = ast_new_assign_expr(op, lhs, rhs);
+        } else if (op == TokenKind_assign_add) {
+            next_token(p);
+            rhs = parse_logical_or_expr(p);
+            lhs = ast_new_assign_add_expr(lhs, rhs);
+        } else if (op == TokenKind_assign_sub) {
+            next_token(p);
+            rhs = parse_logical_or_expr(p);
+            lhs = ast_new_assign_sub_expr(lhs, rhs);
+        } else {
+            break;
+        }
+    }
+    return lhs;
+}
+
+AstNode* parse_expr(Parser* p) {
+    return parse_assignment_expr(p);
+}
+
+AstNode* parse_return_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_return);
+    if (peek_token(p)->kind == TokenKind_semicolon) {
+        next_token(p);
+        return ast_new(AstNodeKind_return_stmt);
+    }
+
+    AstNode* expr = parse_expr(p);
+    expect(p, TokenKind_semicolon);
+
+    AstNode* ret = ast_new(AstNodeKind_return_stmt);
+    ret->node_expr = expr;
+    return ret;
+}
+
+AstNode* parse_if_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_if);
+    expect(p, TokenKind_paren_l);
+    AstNode* cond = parse_expr(p);
+    expect(p, TokenKind_paren_r);
+    AstNode* then_body = parse_stmt(p);
+    AstNode* else_body = NULL;
+    if (peek_token(p)->kind == TokenKind_keyword_else) {
+        next_token(p);
+        else_body = parse_stmt(p);
+    }
+
+    AstNode* stmt = ast_new(AstNodeKind_if_stmt);
+    stmt->node_cond = cond;
+    stmt->node_then = then_body;
+    stmt->node_else = else_body;
+    return stmt;
+}
+
+AstNode* parse_for_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_for);
+    expect(p, TokenKind_paren_l);
+    AstNode* init = NULL;
+    AstNode* cond = NULL;
+    AstNode* update = NULL;
+    if (peek_token(p)->kind != TokenKind_semicolon) {
+        init = parse_expr(p);
+    }
+    expect(p, TokenKind_semicolon);
+    if (peek_token(p)->kind != TokenKind_semicolon) {
+        cond = parse_expr(p);
+    } else {
+        cond = ast_new_int(1);
+    }
+    expect(p, TokenKind_semicolon);
+    if (peek_token(p)->kind != TokenKind_paren_r) {
+        update = parse_expr(p);
+    }
+    expect(p, TokenKind_paren_r);
+    AstNode* body = parse_stmt(p);
+
+    AstNode* stmt = ast_new(AstNodeKind_for_stmt);
+    stmt->node_cond = cond;
+    stmt->node_init = init;
+    stmt->node_update = update;
+    stmt->node_body = body;
+    return stmt;
+}
+
+AstNode* parse_while_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_while);
+    expect(p, TokenKind_paren_l);
+    AstNode* cond = parse_expr(p);
+    expect(p, TokenKind_paren_r);
+    AstNode* body = parse_stmt(p);
+
+    AstNode* stmt = ast_new(AstNodeKind_for_stmt);
+    stmt->node_cond = cond;
+    stmt->node_body = body;
+    return stmt;
+}
+
+AstNode* parse_do_while_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_do);
+    AstNode* body = parse_stmt(p);
+    expect(p, TokenKind_keyword_while);
+    expect(p, TokenKind_paren_l);
+    AstNode* cond = parse_expr(p);
+    expect(p, TokenKind_paren_r);
+    expect(p, TokenKind_semicolon);
+
+    AstNode* stmt = ast_new(AstNodeKind_do_while_stmt);
+    stmt->node_cond = cond;
+    stmt->node_body = body;
+    return stmt;
+}
+
+AstNode* parse_break_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_break);
+    expect(p, TokenKind_semicolon);
+    return ast_new(AstNodeKind_break_stmt);
+}
+
+AstNode* parse_continue_stmt(Parser* p) {
+    expect(p, TokenKind_keyword_continue);
+    expect(p, TokenKind_semicolon);
+    return ast_new(AstNodeKind_continue_stmt);
+}
+
+AstNode* parse_var_decl(Parser* p) {
+    Type* ty = parse_type(p);
+    if (!type_is_unsized(ty)) {
+        fatal_error("parse_var_decl: invalid type for variable");
+    }
+    String* name = parse_ident(p);
+
+    AstNode* init = NULL;
+    if (peek_token(p)->kind == TokenKind_assign) {
+        next_token(p);
+        init = parse_expr(p);
+    }
+    expect(p, TokenKind_semicolon);
+
+    if (find_lvar(p, name) != -1 || find_gvar(p, name) != -1) {
+        char* buf = calloc(1024, sizeof(char));
+        sprintf(buf, "parse_var_decl: %.*s redeclared", name->len, name->data);
+        fatal_error(buf);
+    }
+    p->lvars[p->n_lvars].name.data = name->data;
+    p->lvars[p->n_lvars].name.len = name->len;
+    p->lvars[p->n_lvars].ty = ty;
+    ++p->n_lvars;
+
+    AstNode* ret;
+    if (init) {
+        AstNode* lhs = ast_new(AstNodeKind_lvar);
+        lhs->name.data = name->data;
+        lhs->name.len = name->len;
+        lhs->node_idx = p->n_lvars - 1;
+        lhs->ty = ty;
+        AstNode* assign = ast_new_assign_expr(TokenKind_assign, lhs, init);
+        ret = ast_new(AstNodeKind_expr_stmt);
+        ret->node_expr = assign;
+    } else {
+        ret = ast_new(AstNodeKind_lvar_decl);
+    }
+    return ret;
+}
+
+AstNode* parse_expr_stmt(Parser* p) {
+    AstNode* e = parse_expr(p);
+    expect(p, TokenKind_semicolon);
+    AstNode* stmt = ast_new(AstNodeKind_expr_stmt);
+    stmt->node_expr = e;
+    return stmt;
+}
+
+AstNode* parse_block_stmt(Parser* p) {
+    AstNode* list = ast_new_list(1024);
+    expect(p, TokenKind_brace_l);
+    while (peek_token(p)->kind != TokenKind_brace_r) {
+        AstNode* stmt = parse_stmt(p);
+        ast_append(list, stmt);
+    }
+    expect(p, TokenKind_brace_r);
+    return list;
+}
+
+AstNode* parse_stmt(Parser* p) {
+    Token* t = peek_token(p);
+    if (t->kind == TokenKind_keyword_return) {
+        return parse_return_stmt(p);
+    } else if (t->kind == TokenKind_keyword_if) {
+        return parse_if_stmt(p);
+    } else if (t->kind == TokenKind_keyword_for) {
+        return parse_for_stmt(p);
+    } else if (t->kind == TokenKind_keyword_while) {
+        return parse_while_stmt(p);
+    } else if (t->kind == TokenKind_keyword_do) {
+        return parse_do_while_stmt(p);
+    } else if (t->kind == TokenKind_keyword_break) {
+        return parse_break_stmt(p);
+    } else if (t->kind == TokenKind_keyword_continue) {
+        return parse_continue_stmt(p);
+    } else if (t->kind == TokenKind_brace_l) {
+        return parse_block_stmt(p);
+    } else if (is_type_token(p, t)) {
+        return parse_var_decl(p);
+    } else {
+        return parse_expr_stmt(p);
+    }
+}
+
+void enter_func(Parser* p) {
+    p->lvars = calloc(LVAR_MAX, sizeof(LocalVar));
+    p->n_lvars = 0;
+}
+
+void register_params(Parser* p, AstNode* params) {
+    int i;
+    for (i = 0; i < params->node_len; ++i) {
+        AstNode* param = params->node_items + i;
+        p->lvars[p->n_lvars].name.data = param->name.data;
+        p->lvars[p->n_lvars].name.len = param->name.len;
+        p->lvars[p->n_lvars].ty = param->ty;
+        ++p->n_lvars;
+    }
+}
+
+void register_func(Parser* p, const String* name, Type* ty) {
+    p->funcs[p->n_funcs].name.data = name->data;
+    p->funcs[p->n_funcs].name.len = name->len;
+    p->funcs[p->n_funcs].ty = ty;
+    ++p->n_funcs;
+}
+
+AstNode* parse_param(Parser* p) {
+    Type* ty = parse_type(p);
+    String* name = NULL;
+    TokenKind tk = peek_token(p)->kind;
+    if (tk != TokenKind_comma && tk != TokenKind_paren_r) {
+        name = parse_ident(p);
+    }
+    AstNode* param = ast_new(AstNodeKind_param);
+    param->ty = ty;
+    if (name) {
+        param->name.data = name->data;
+        param->name.len = name->len;
+    }
+    return param;
+}
+
+AstNode* parse_param_list(Parser* p) {
+    int has_void = 0;
+    AstNode* list = ast_new_list(6);
+    while (peek_token(p)->kind != TokenKind_paren_r) {
+        if (peek_token(p)->kind == TokenKind_ellipsis) {
+            next_token(p);
+            break;
+        }
+        AstNode* param = parse_param(p);
+        has_void = has_void || param->ty->kind == TypeKind_void;
+        ast_append(list, param);
+        if (peek_token(p)->kind == TokenKind_comma) {
+            next_token(p);
+        } else {
+            break;
+        }
+    }
+    if (list->node_len > 6) {
+        fatal_error("too many parameters");
+    }
+    if (has_void) {
+        if (list->node_len != 1) {
+            fatal_error("invalid use of void param");
+        }
+        list->node_len = 0;
+    }
+    return list;
+}
+
+AstNode* parse_func_decl_or_def(Parser* p) {
+    Type* ty = parse_type(p);
+    String* name = parse_ident(p);
+    register_func(p, name, ty);
+    expect(p, TokenKind_paren_l);
+    AstNode* params = parse_param_list(p);
+    expect(p, TokenKind_paren_r);
+    if (peek_token(p)->kind == TokenKind_semicolon) {
+        next_token(p);
+        return ast_new(AstNodeKind_func_decl);
+    }
+    enter_func(p);
+    register_params(p, params);
+    AstNode* body = parse_block_stmt(p);
+    AstNode* func = ast_new(AstNodeKind_func_def);
+    func->ty = ty;
+    func->name.data = name->data;
+    func->name.len = name->len;
+    func->node_params = params;
+    func->node_body = body;
+    return func;
+}
+
+AstNode* parse_struct_member(Parser* p) {
+    Type* ty = parse_type(p);
+    String* name = parse_ident(p);
+    expect(p, TokenKind_semicolon);
+    AstNode* member = ast_new(AstNodeKind_struct_member);
+    member->name.data = name->data;
+    member->name.len = name->len;
+    member->ty = ty;
+    return member;
+}
+
+AstNode* parse_struct_members(Parser* p) {
+    AstNode* list = ast_new_list(16);
+    while (peek_token(p)->kind != TokenKind_brace_r) {
+        AstNode* member = parse_struct_member(p);
+        ast_append(list, member);
+    }
+    return list;
+}
+
+AstNode* parse_struct_decl_or_def(Parser* p) {
+    expect(p, TokenKind_keyword_struct);
+    String* name = parse_ident(p);
+
+    if (peek_token(p)->kind != TokenKind_semicolon && peek_token(p)->kind != TokenKind_brace_l) {
+        p->pos = p->pos - 2;
+        return parse_func_decl_or_def(p);
+    }
+
+    int struct_idx = find_struct(p, name);
+    if (struct_idx == -1) {
+        struct_idx = p->n_structs;
+        p->structs[struct_idx].kind = AstNodeKind_struct_def;
+        p->structs[struct_idx].name.data = name->data;
+        p->structs[struct_idx].name.len = name->len;
+        ++p->n_structs;
+    }
+    if (peek_token(p)->kind == TokenKind_semicolon) {
+        next_token(p);
+        return ast_new(AstNodeKind_struct_decl);
+    }
+    if (p->structs[struct_idx].node_members) {
+        char* buf = calloc(1024, sizeof(char));
+        sprintf(buf, "parse_struct_decl_or_def: struct %.*s redefined", name->len, name->data);
+        fatal_error(buf);
+    }
+    expect(p, TokenKind_brace_l);
+    AstNode* members = parse_struct_members(p);
+    expect(p, TokenKind_brace_r);
+    expect(p, TokenKind_semicolon);
+    p->structs[struct_idx].node_members = members;
+    return p->structs + struct_idx;
+}
+
+AstNode* parse_enum_member(Parser* p) {
+    String* name = parse_ident(p);
+    AstNode* member = ast_new(AstNodeKind_enum_member);
+    member->name.data = name->data;
+    member->name.len = name->len;
+    return member;
+}
+
+AstNode* parse_enum_members(Parser* p) {
+    int next_value = 0;
+    AstNode* list = ast_new_list(256);
+    while (peek_token(p)->kind != TokenKind_brace_r) {
+        AstNode* member = parse_enum_member(p);
+        member->node_int_value = next_value;
+        ++next_value;
+        ast_append(list, member);
+        if (peek_token(p)->kind != TokenKind_comma) {
+            break;
+        }
+        next_token(p);
+    }
+    return list;
+}
+
+AstNode* parse_enum_def(Parser* p) {
+    expect(p, TokenKind_keyword_enum);
+    String* name = parse_ident(p);
+
+    if (peek_token(p)->kind != TokenKind_brace_l) {
+        p->pos = p->pos - 2;
+        return parse_func_decl_or_def(p);
+    }
+
+    int enum_idx = find_enum(p, name);
+    if (enum_idx == -1) {
+        enum_idx = p->n_enums;
+        p->enums[enum_idx].kind = AstNodeKind_enum_def;
+        p->enums[enum_idx].name.data = name->data;
+        p->enums[enum_idx].name.len = name->len;
+        ++p->n_enums;
+    } else {
+        char* buf = calloc(1024, sizeof(char));
+        sprintf(buf, "parse_enum_def: enum %.*s redefined", name->len, name->data);
+        fatal_error(buf);
+    }
+    expect(p, TokenKind_brace_l);
+    AstNode* members = parse_enum_members(p);
+    expect(p, TokenKind_brace_r);
+    expect(p, TokenKind_semicolon);
+    p->enums[enum_idx].node_members = members;
+    return p->enums + enum_idx;
+}
+
+AstNode* parse_typedef_decl(Parser* p) {
+    expect(p, TokenKind_keyword_typeof);
+    Type* ty = parse_type(p);
+    String* name = parse_ident(p);
+    expect(p, TokenKind_semicolon);
+    AstNode* decl = ast_new(AstNodeKind_typedef_decl);
+    decl->name.data = name->data;
+    decl->name.len = name->len;
+    decl->ty = ty;
+    p->typedefs[p->n_typedefs].name.data = name->data;
+    p->typedefs[p->n_typedefs].name.len = name->len;
+    p->typedefs[p->n_typedefs].ty = ty;
+    ++p->n_typedefs;
+    return decl;
+}
+
+AstNode* parse_extern_var_decl(Parser* p) {
+    expect(p, TokenKind_keyword_extern);
+    Type* ty = parse_type(p);
+    if (!type_is_unsized(ty)) {
+        fatal_error("parse_extern_var_decl: invalid type for variable");
+    }
+    String* name = parse_ident(p);
+    expect(p, TokenKind_semicolon);
+
+    if (find_lvar(p, name) != -1 || find_gvar(p, name) != -1) {
+        char* buf = calloc(1024, sizeof(char));
+        sprintf(buf, "parse_extern_var_decl: %.*s redeclared", name->len, name->data);
+        fatal_error(buf);
+    }
+    p->gvars[p->n_gvars].name.data = name->data;
+    p->gvars[p->n_gvars].name.len = name->len;
+    p->gvars[p->n_gvars].ty = ty;
+    ++p->n_gvars;
+
+    return ast_new(AstNodeKind_gvar_decl);
+}
+
+AstNode* parse_toplevel(Parser* p) {
+    TokenKind tk = peek_token(p)->kind;
+    if (tk == TokenKind_keyword_struct) {
+        return parse_struct_decl_or_def(p);
+    } else if (tk == TokenKind_keyword_enum) {
+        return parse_enum_def(p);
+    } else if (tk == TokenKind_keyword_typeof) {
+        return parse_typedef_decl(p);
+    } else if (tk == TokenKind_keyword_extern) {
+        return parse_extern_var_decl(p);
+    } else {
+        return parse_func_decl_or_def(p);
+    }
+}
+
+Program* parse(Token* tokens) {
+    Parser* p = parser_new(tokens);
+    AstNode* funcs = ast_new_list(1024);
+    while (eof(p)) {
+        AstNode* n = parse_toplevel(p);
+        if (n->kind == AstNodeKind_func_def) {
+            ast_append(funcs, n);
+        }
+    }
+    Program* prog = calloc(1, sizeof(Program));
+    prog->funcs = funcs;
+    prog->str_literals = p->str_literals;
+    return prog;
+}