feat: support global variables with initializer

3 files changed, 36 insertions, 2 deletions

diff --git a/codegen.c b/codegen.c
index d6f320a..f71d74a 100644
--- a/codegen.c
+++ b/codegen.c
@@ -564,10 +564,21 @@ void codegen(Program* prog) {
         printf("  .string \"%s\"\n\n", prog->str_literals[i]);
     }
 
-    printf(".bss\n\n");
+    printf(".data\n\n");
     for (int i = 0; i < prog->vars->node_len; ++i) {
         AstNode* var = prog->vars->node_items + i;
-        printf("  .lcomm %.*s, %d\n", var->name.len, var->name.data, type_sizeof(var->ty));
+        if (var->node_expr) {
+            if (var->ty->kind == TypeKind_char)
+                printf("  %.*s: .byte %d\n", var->name.len, var->name.data, var->node_expr->node_int_value);
+            else if (var->ty->kind == TypeKind_short)
+                printf("  %.*s: .word %d\n", var->name.len, var->name.data, var->node_expr->node_int_value);
+            else if (var->ty->kind == TypeKind_int)
+                printf("  %.*s: .int %d\n", var->name.len, var->name.data, var->node_expr->node_int_value);
+            else
+                unimplemented();
+        } else {
+            printf("  %.*s: .zero %d\n", var->name.len, var->name.data, type_sizeof(var->ty));
+        }
     }
 
     printf(".globl main\n\n");
diff --git a/parse.c b/parse.c
index a185241..09d962d 100644
--- a/parse.c
+++ b/parse.c
@@ -1058,6 +1058,11 @@ AstNode* parse_global_var_decl(Parser* p, Type* ty, String* name) {
         ty = type_new_array(ty, size);
     }
 
+    AstNode* init = NULL;
+    if (peek_token(p)->kind == TokenKind_assign) {
+        next_token(p);
+        init = parse_assignment_expr(p);
+    }
     expect(p, TokenKind_semicolon);
 
     if (find_gvar(p, name) != -1) {
@@ -1071,6 +1076,7 @@ AstNode* parse_global_var_decl(Parser* p, Type* ty, String* name) {
     AstNode* ret = ast_new(AstNodeKind_gvar_decl);
     ret->name = *name;
     ret->ty = ty;
+    ret->node_expr = init;
     return ret;
 }
 
diff --git a/tests/092.sh b/tests/092.sh
new file mode 100644
index 0000000..00dcb44
--- /dev/null
+++ b/tests/092.sh
@@ -0,0 +1,17 @@
+set -e
+
+cat <<'EOF' > expected
+42 123 999
+EOF
+
+bash ../../test_diff.sh <<'EOF'
+int printf();
+
+char a = 42;
+short b = 123;
+int c = 999;
+
+int main() {
+    printf("%d %d %d\n", a, b, c);
+}
+EOF