1 files changed, 118 insertions, 0 deletions
diff --git a/mini_builtin.c b/mini_builtin.c
new file mode 100644
index 0000000000..75ea94d37d
--- /dev/null
+++ b/mini_builtin.c
@@ -0,0 +1,118 @@
+#include "internal.h"
+#include "internal/array.h"
+#include "internal/eval.h"
+#include "iseq.h"
+#include "vm_core.h"
+#include "builtin.h"
+
+#include "miniprelude.c"
+
+static VALUE
+prelude_ast_value(VALUE name, VALUE code, int line)
+{
+    rb_ast_t *ast;
+    VALUE ast_value = rb_parser_compile_string_path(rb_parser_new(), name, code, line);
+    ast = rb_ruby_ast_data_get(ast_value);
+    if (!ast || !ast->body.root) {
+        if (ast) rb_ast_dispose(ast);
+        rb_exc_raise(rb_errinfo());
+    }
+    return ast_value;
+}
+
+static void
+pm_prelude_load(pm_parse_result_t *result, VALUE name, VALUE code, int line)
+{
+    pm_parse_result_init(result);
+    pm_options_line_set(result->options, line);
+    VALUE error = pm_parse_string(result, code, name, NULL);
+
+    if (!NIL_P(error)) {
+        pm_parse_result_free(result);
+        rb_exc_raise(error);
+    }
+}
+
+static const rb_iseq_t *
+builtin_iseq_load(const char *feature_name, const struct rb_builtin_function *table)
+{
+    VALUE name_str = 0;
+    int start_line;
+    const rb_iseq_t *iseq;
+    VALUE code = rb_builtin_find(feature_name, &name_str, &start_line);
+    if (NIL_P(code)) {
+        rb_fatal("builtin_iseq_load: can not find %s; "
+                 "probably miniprelude.c is out of date",
+                 feature_name);
+    }
+
+    rb_vm_t *vm = GET_VM();
+    static const rb_compile_option_t optimization = {
+        .inline_const_cache = TRUE,
+        .peephole_optimization = TRUE,
+        .tailcall_optimization = FALSE,
+        .specialized_instruction = TRUE,
+        .operands_unification = TRUE,
+        .instructions_unification = TRUE,
+        .frozen_string_literal = TRUE,
+        .debug_frozen_string_literal = FALSE,
+        .coverage_enabled = FALSE,
+        .debug_level = 0,
+    };
+
+    if (rb_ruby_prism_p()) {
+        pm_parse_result_t result;
+        pm_prelude_load(&result, name_str, code, start_line);
+
+        vm->builtin_function_table = table;
+        int error_state;
+        iseq = pm_iseq_new_with_opt(&result.node, name_str, name_str, Qnil, 0, NULL, 0, ISEQ_TYPE_TOP, &optimization, &error_state);
+
+        vm->builtin_function_table = NULL;
+        pm_parse_result_free(&result);
+
+        if (error_state) {
+            RUBY_ASSERT(iseq == NULL);
+            rb_jump_tag(error_state);
+        }
+    }
+    else {
+        VALUE ast_value = prelude_ast_value(name_str, code, start_line);
+        rb_ast_t *ast = rb_ruby_ast_data_get(ast_value);
+
+        vm->builtin_function_table = table;
+        iseq = rb_iseq_new_with_opt(ast_value, name_str, name_str, Qnil, 0, NULL, 0, ISEQ_TYPE_TOP, &optimization, Qnil);
+
+        vm->builtin_function_table = NULL;
+        rb_ast_dispose(ast);
+    }
+
+    // for debug
+    if (0 && strcmp("prelude", feature_name) == 0) {
+        rb_io_write(rb_stdout, rb_iseq_disasm((const rb_iseq_t *)iseq));
+    }
+
+    BUILTIN_LOADED(feature_name, iseq);
+
+    return iseq;
+}
+
+void
+rb_load_with_builtin_functions(const char *feature_name, const struct rb_builtin_function *table)
+{
+    const rb_iseq_t *iseq = builtin_iseq_load(feature_name, table);
+    rb_iseq_eval(iseq, rb_root_box());
+}
+
+VALUE
+rb_define_gem_modules(VALUE _a, VALUE _b)
+{
+    // do nothing - moniruby doesn't load gem_prelude.rb.
+    return Qnil;
+}
+
+void
+rb_load_gem_prelude(VALUE _)
+{
+    // do nothing - miniruby doesn't support loading RubyGems.
+}