Fresh start

1 files changed, 1796 insertions, 0 deletions

diff --git a/jni/ruby/vm_method.c b/jni/ruby/vm_method.c
new file mode 100644
index 0000000..3159b22
--- /dev/null
+++ b/jni/ruby/vm_method.c
@@ -0,0 +1,1796 @@
+/*
+ * This file is included by vm.c
+ */
+
+#if OPT_GLOBAL_METHOD_CACHE
+#ifndef GLOBAL_METHOD_CACHE_SIZE
+#define GLOBAL_METHOD_CACHE_SIZE 0x800
+#endif
+#define LSB_ONLY(x) ((x) & ~((x) - 1))
+#define POWER_OF_2_P(x) ((x) == LSB_ONLY(x))
+#if !POWER_OF_2_P(GLOBAL_METHOD_CACHE_SIZE)
+# error GLOBAL_METHOD_CACHE_SIZE must be power of 2
+#endif
+#ifndef GLOBAL_METHOD_CACHE_MASK
+#define GLOBAL_METHOD_CACHE_MASK (GLOBAL_METHOD_CACHE_SIZE-1)
+#endif
+
+#define GLOBAL_METHOD_CACHE_KEY(c,m) ((((c)>>3)^(m))&(global_method_cache.mask))
+#define GLOBAL_METHOD_CACHE(c,m) (global_method_cache.entries + GLOBAL_METHOD_CACHE_KEY(c,m))
+#else
+#define GLOBAL_METHOD_CACHE(c,m) (rb_bug("global method cache disabled improperly"), NULL)
+#endif
+#include "method.h"
+
+#define NOEX_NOREDEF 0
+#ifndef NOEX_NOREDEF
+#define NOEX_NOREDEF NOEX_RESPONDS
+#endif
+
+static void rb_vm_check_redefinition_opt_method(const rb_method_entry_t *me, VALUE klass);
+
+#define object_id           idObject_id
+#define added               idMethod_added
+#define singleton_added     idSingleton_method_added
+#define removed             idMethod_removed
+#define singleton_removed   idSingleton_method_removed
+#define undefined           idMethod_undefined
+#define singleton_undefined idSingleton_method_undefined
+#define attached            id__attached__
+
+struct cache_entry {
+    rb_serial_t method_state;
+    rb_serial_t class_serial;
+    ID mid;
+    rb_method_entry_t* me;
+    VALUE defined_class;
+};
+
+#if OPT_GLOBAL_METHOD_CACHE
+static struct {
+    unsigned int size;
+    unsigned int mask;
+    struct cache_entry *entries;
+} global_method_cache = {
+    GLOBAL_METHOD_CACHE_SIZE,
+    GLOBAL_METHOD_CACHE_MASK,
+};
+#endif
+
+#define ruby_running (GET_VM()->running)
+/* int ruby_running = 0; */
+
+static void
+rb_class_clear_method_cache(VALUE klass)
+{
+    RCLASS_SERIAL(klass) = rb_next_class_serial();
+    rb_class_foreach_subclass(klass, rb_class_clear_method_cache);
+}
+
+void
+rb_clear_cache(void)
+{
+    rb_warning("rb_clear_cache() is deprecated.");
+    INC_GLOBAL_METHOD_STATE();
+    INC_GLOBAL_CONSTANT_STATE();
+}
+
+void
+rb_clear_constant_cache(void)
+{
+    INC_GLOBAL_CONSTANT_STATE();
+}
+
+void
+rb_clear_method_cache_by_class(VALUE klass)
+{
+    if (klass && klass != Qundef) {
+	int global = klass == rb_cBasicObject || klass == rb_cObject || klass == rb_mKernel;
+
+	if (RUBY_DTRACE_METHOD_CACHE_CLEAR_ENABLED()) {
+	    RUBY_DTRACE_METHOD_CACHE_CLEAR(global ? "global" : rb_class2name(klass), rb_sourcefile(), rb_sourceline());
+	}
+
+	if (global) {
+	    INC_GLOBAL_METHOD_STATE();
+	}
+	else {
+	    rb_class_clear_method_cache(klass);
+	}
+    }
+}
+
+VALUE
+rb_f_notimplement(int argc, const VALUE *argv, VALUE obj)
+{
+    rb_notimplement();
+
+    UNREACHABLE;
+}
+
+static void
+rb_define_notimplement_method_id(VALUE mod, ID id, rb_method_flag_t noex)
+{
+    rb_add_method(mod, id, VM_METHOD_TYPE_NOTIMPLEMENTED, 0, noex);
+}
+
+void
+rb_add_method_cfunc(VALUE klass, ID mid, VALUE (*func)(ANYARGS), int argc, rb_method_flag_t noex)
+{
+    if (argc < -2 || 15 < argc) rb_raise(rb_eArgError, "arity out of range: %d for -2..15", argc);
+    if (func != rb_f_notimplement) {
+	rb_method_cfunc_t opt;
+	opt.func = func;
+	opt.argc = argc;
+	rb_add_method(klass, mid, VM_METHOD_TYPE_CFUNC, &opt, noex);
+    }
+    else {
+	rb_define_notimplement_method_id(klass, mid, noex);
+    }
+}
+
+void
+rb_unlink_method_entry(rb_method_entry_t *me)
+{
+    struct unlinked_method_entry_list_entry *ume = ALLOC(struct unlinked_method_entry_list_entry);
+    ume->me = me;
+    ume->next = GET_VM()->unlinked_method_entry_list;
+    GET_VM()->unlinked_method_entry_list = ume;
+}
+
+void
+rb_gc_mark_unlinked_live_method_entries(void *pvm)
+{
+    rb_vm_t *vm = pvm;
+    struct unlinked_method_entry_list_entry *ume = vm->unlinked_method_entry_list;
+
+    while (ume) {
+	if (ume->me->mark) {
+	    rb_mark_method_entry(ume->me);
+	}
+	ume = ume->next;
+    }
+}
+
+void
+rb_sweep_method_entry(void *pvm)
+{
+    rb_vm_t *vm = pvm;
+    struct unlinked_method_entry_list_entry **prev_ume = &vm->unlinked_method_entry_list, *ume = *prev_ume, *curr_ume;
+
+    while (ume) {
+	if (ume->me->mark) {
+	    ume->me->mark = 0;
+	    prev_ume = &ume->next;
+	    ume = *prev_ume;
+	}
+	else {
+	    rb_free_method_entry(ume->me);
+
+	    curr_ume = ume;
+	    ume = ume->next;
+	    *prev_ume = ume;
+	    xfree(curr_ume);
+	}
+    }
+}
+
+static void
+release_method_definition(rb_method_definition_t *def)
+{
+    if (def == 0)
+	return;
+    if (def->alias_count == 0) {
+	if (def->type == VM_METHOD_TYPE_REFINED &&
+	    def->body.orig_me) {
+	    rb_free_method_entry(def->body.orig_me);
+	}
+	xfree(def);
+    }
+    else if (def->alias_count > 0) {
+	def->alias_count--;
+    }
+}
+
+void
+rb_free_method_entry(rb_method_entry_t *me)
+{
+    release_method_definition(me->def);
+    xfree(me);
+}
+
+static inline rb_method_entry_t *search_method(VALUE klass, ID id, VALUE *defined_class_ptr);
+static int rb_method_definition_eq(const rb_method_definition_t *d1, const rb_method_definition_t *d2);
+
+static inline rb_method_entry_t *
+lookup_method_table(VALUE klass, ID id)
+{
+    st_data_t body;
+    st_table *m_tbl = RCLASS_M_TBL(klass);
+    if (st_lookup(m_tbl, id, &body)) {
+	return (rb_method_entry_t *) body;
+    }
+    else {
+	return 0;
+    }
+}
+
+static void
+make_method_entry_refined(rb_method_entry_t *me)
+{
+    rb_method_definition_t *new_def;
+
+    if (me->def && me->def->type == VM_METHOD_TYPE_REFINED)
+	return;
+
+    new_def = ALLOC(rb_method_definition_t);
+    new_def->type = VM_METHOD_TYPE_REFINED;
+    new_def->original_id = me->called_id;
+    new_def->alias_count = 0;
+    new_def->body.orig_me = ALLOC(rb_method_entry_t);
+    *new_def->body.orig_me = *me;
+    rb_vm_check_redefinition_opt_method(me, me->klass);
+    if (me->def) me->def->alias_count++;
+    me->flag = NOEX_WITH_SAFE(NOEX_PUBLIC);
+    me->def = new_def;
+}
+
+void
+rb_add_refined_method_entry(VALUE refined_class, ID mid)
+{
+    rb_method_entry_t *me = lookup_method_table(refined_class, mid);
+
+    if (me) {
+	make_method_entry_refined(me);
+	rb_clear_method_cache_by_class(refined_class);
+    }
+    else {
+	rb_add_method(refined_class, mid, VM_METHOD_TYPE_REFINED, 0,
+		      NOEX_PUBLIC);
+    }
+}
+
+static rb_method_entry_t *
+rb_method_entry_make(VALUE klass, ID mid, rb_method_type_t type,
+		     rb_method_definition_t *def, rb_method_flag_t noex,
+		     VALUE defined_class)
+{
+    rb_method_entry_t *me;
+#if NOEX_NOREDEF
+    VALUE rklass;
+#endif
+    st_table *mtbl;
+    st_data_t data;
+    int make_refined = 0;
+
+    if (NIL_P(klass)) {
+	klass = rb_cObject;
+    }
+    if (!FL_TEST(klass, FL_SINGLETON) &&
+	type != VM_METHOD_TYPE_NOTIMPLEMENTED &&
+	type != VM_METHOD_TYPE_ZSUPER) {
+	switch (mid) {
+	  case idInitialize:
+	  case idInitialize_copy:
+	  case idInitialize_clone:
+	  case idInitialize_dup:
+	  case idRespond_to_missing:
+	    noex |= NOEX_PRIVATE;
+	}
+    }
+
+    rb_frozen_class_p(klass);
+#if NOEX_NOREDEF
+    rklass = klass;
+#endif
+    if (FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
+	VALUE refined_class =
+	    rb_refinement_module_get_refined_class(klass);
+
+	rb_add_refined_method_entry(refined_class, mid);
+    }
+    if (type == VM_METHOD_TYPE_REFINED) {
+	rb_method_entry_t *old_me =
+	    lookup_method_table(RCLASS_ORIGIN(klass), mid);
+	if (old_me) rb_vm_check_redefinition_opt_method(old_me, klass);
+    }
+    else {
+	klass = RCLASS_ORIGIN(klass);
+    }
+    mtbl = RCLASS_M_TBL(klass);
+
+    /* check re-definition */
+    if (st_lookup(mtbl, mid, &data)) {
+	rb_method_entry_t *old_me = (rb_method_entry_t *)data;
+	rb_method_definition_t *old_def = old_me->def;
+
+	if (rb_method_definition_eq(old_def, def)) return old_me;
+#if NOEX_NOREDEF
+	if (old_me->flag & NOEX_NOREDEF) {
+	    rb_raise(rb_eTypeError, "cannot redefine %"PRIsVALUE"#%"PRIsVALUE,
+		     rb_class_name(rklass), rb_id2str(mid));
+	}
+#endif
+	rb_vm_check_redefinition_opt_method(old_me, klass);
+	if (old_def->type == VM_METHOD_TYPE_REFINED)
+	    make_refined = 1;
+
+	if (RTEST(ruby_verbose) &&
+	    type != VM_METHOD_TYPE_UNDEF &&
+	    old_def->alias_count == 0 &&
+	    old_def->type != VM_METHOD_TYPE_UNDEF &&
+	    old_def->type != VM_METHOD_TYPE_ZSUPER) {
+	    rb_iseq_t *iseq = 0;
+
+	    rb_warning("method redefined; discarding old %"PRIsVALUE, rb_id2str(mid));
+	    switch (old_def->type) {
+	      case VM_METHOD_TYPE_ISEQ:
+		iseq = old_def->body.iseq;
+		break;
+	      case VM_METHOD_TYPE_BMETHOD:
+		iseq = rb_proc_get_iseq(old_def->body.proc, 0);
+		break;
+	      default:
+		break;
+	    }
+	    if (iseq && !NIL_P(iseq->location.path)) {
+		int line = iseq->line_info_table ? FIX2INT(rb_iseq_first_lineno(iseq->self)) : 0;
+		rb_compile_warning(RSTRING_PTR(iseq->location.path), line,
+				   "previous definition of %"PRIsVALUE" was here",
+				   rb_id2str(old_def->original_id));
+	    }
+	}
+
+	rb_unlink_method_entry(old_me);
+    }
+
+    mid = SYM2ID(ID2SYM(mid));
+
+    me = ALLOC(rb_method_entry_t);
+
+    rb_clear_method_cache_by_class(klass);
+
+    me->flag = NOEX_WITH_SAFE(noex);
+    me->mark = 0;
+    me->called_id = mid;
+    RB_OBJ_WRITE(klass, &me->klass, defined_class);
+    me->def = def;
+
+    if (def) {
+	def->alias_count++;
+
+	switch(def->type) {
+	  case VM_METHOD_TYPE_ISEQ:
+	    RB_OBJ_WRITTEN(klass, Qundef, def->body.iseq->self);
+	    break;
+	  case VM_METHOD_TYPE_IVAR:
+	    RB_OBJ_WRITTEN(klass, Qundef, def->body.attr.location);
+	    break;
+	  case VM_METHOD_TYPE_BMETHOD:
+	    RB_OBJ_WRITTEN(klass, Qundef, def->body.proc);
+	    break;
+	  default:;
+	    /* ignore */
+	}
+    }
+
+    /* check mid */
+    if (klass == rb_cObject && mid == idInitialize) {
+	rb_warn("redefining Object#initialize may cause infinite loop");
+    }
+    /* check mid */
+    if (mid == object_id || mid == id__send__) {
+	if (type == VM_METHOD_TYPE_ISEQ && search_method(klass, mid, 0)) {
+	    rb_warn("redefining `%s' may cause serious problems", rb_id2name(mid));
+	}
+    }
+
+    if (make_refined) {
+	make_method_entry_refined(me);
+    }
+
+    st_insert(mtbl, mid, (st_data_t) me);
+
+    return me;
+}
+
+#define CALL_METHOD_HOOK(klass, hook, mid) do {		\
+	const VALUE arg = ID2SYM(mid);			\
+	VALUE recv_class = (klass);			\
+	ID hook_id = (hook);				\
+	if (FL_TEST((klass), FL_SINGLETON)) {		\
+	    recv_class = rb_ivar_get((klass), attached);	\
+	    hook_id = singleton_##hook;			\
+	}						\
+	rb_funcall2(recv_class, hook_id, 1, &arg);	\
+    } while (0)
+
+static void
+method_added(VALUE klass, ID mid)
+{
+    if (ruby_running) {
+	CALL_METHOD_HOOK(klass, added, mid);
+    }
+}
+
+static VALUE
+(*call_cfunc_invoker_func(int argc))(VALUE (*func)(ANYARGS), VALUE recv, int argc, const VALUE *)
+{
+    switch (argc) {
+      case -2: return &call_cfunc_m2;
+      case -1: return &call_cfunc_m1;
+      case 0: return &call_cfunc_0;
+      case 1: return &call_cfunc_1;
+      case 2: return &call_cfunc_2;
+      case 3: return &call_cfunc_3;
+      case 4: return &call_cfunc_4;
+      case 5: return &call_cfunc_5;
+      case 6: return &call_cfunc_6;
+      case 7: return &call_cfunc_7;
+      case 8: return &call_cfunc_8;
+      case 9: return &call_cfunc_9;
+      case 10: return &call_cfunc_10;
+      case 11: return &call_cfunc_11;
+      case 12: return &call_cfunc_12;
+      case 13: return &call_cfunc_13;
+      case 14: return &call_cfunc_14;
+      case 15: return &call_cfunc_15;
+      default:
+	rb_bug("call_cfunc_func: unsupported length: %d", argc);
+    }
+}
+
+static void
+setup_method_cfunc_struct(rb_method_cfunc_t *cfunc, VALUE (*func)(), int argc)
+{
+    cfunc->func = func;
+    cfunc->argc = argc;
+    cfunc->invoker = call_cfunc_invoker_func(argc);
+}
+
+rb_method_entry_t *
+rb_add_method(VALUE klass, ID mid, rb_method_type_t type, void *opts, rb_method_flag_t noex)
+{
+    rb_thread_t *th;
+    rb_control_frame_t *cfp;
+    int line;
+    rb_method_entry_t *me = rb_method_entry_make(klass, mid, type, 0, noex, klass);
+    rb_method_definition_t *def = ALLOC(rb_method_definition_t);
+    if (me->def && me->def->type == VM_METHOD_TYPE_REFINED) {
+	me->def->body.orig_me->def = def;
+    }
+    else {
+	me->def = def;
+    }
+    def->type = type;
+    def->original_id = mid;
+    def->alias_count = 0;
+    switch (type) {
+      case VM_METHOD_TYPE_ISEQ: {
+	  rb_iseq_t *iseq = (rb_iseq_t *)opts;
+	  *(rb_iseq_t **)&def->body.iseq = iseq;
+	  RB_OBJ_WRITTEN(klass, Qundef, iseq->self);
+	  break;
+      }
+      case VM_METHOD_TYPE_CFUNC:
+	{
+	    rb_method_cfunc_t *cfunc = (rb_method_cfunc_t *)opts;
+	    setup_method_cfunc_struct(&def->body.cfunc, cfunc->func, cfunc->argc);
+	}
+	break;
+      case VM_METHOD_TYPE_ATTRSET:
+      case VM_METHOD_TYPE_IVAR:
+	def->body.attr.id = (ID)(VALUE)opts;
+	RB_OBJ_WRITE(klass, &def->body.attr.location, Qfalse);
+	th = GET_THREAD();
+	cfp = rb_vm_get_ruby_level_next_cfp(th, th->cfp);
+	if (cfp && (line = rb_vm_get_sourceline(cfp))) {
+	    VALUE location = rb_ary_new3(2, cfp->iseq->location.path, INT2FIX(line));
+	    RB_OBJ_WRITE(klass, &def->body.attr.location, rb_ary_freeze(location));
+	}
+	break;
+      case VM_METHOD_TYPE_BMETHOD:
+	RB_OBJ_WRITE(klass, &def->body.proc, (VALUE)opts);
+	break;
+      case VM_METHOD_TYPE_NOTIMPLEMENTED:
+	setup_method_cfunc_struct(&def->body.cfunc, rb_f_notimplement, -1);
+	break;
+      case VM_METHOD_TYPE_OPTIMIZED:
+	def->body.optimize_type = (enum method_optimized_type)opts;
+	break;
+      case VM_METHOD_TYPE_ZSUPER:
+      case VM_METHOD_TYPE_UNDEF:
+	break;
+      case VM_METHOD_TYPE_REFINED:
+	def->body.orig_me = (rb_method_entry_t *) opts;
+	break;
+      default:
+	rb_bug("rb_add_method: unsupported method type (%d)\n", type);
+    }
+    if (type != VM_METHOD_TYPE_UNDEF && type != VM_METHOD_TYPE_REFINED) {
+	method_added(klass, mid);
+    }
+    return me;
+}
+
+static rb_method_entry_t *
+method_entry_set(VALUE klass, ID mid, const rb_method_entry_t *me,
+		 rb_method_flag_t noex, VALUE defined_class)
+{
+    rb_method_type_t type = me->def ? me->def->type : VM_METHOD_TYPE_UNDEF;
+    rb_method_entry_t *newme = rb_method_entry_make(klass, mid, type, me->def, noex,
+						    defined_class);
+    method_added(klass, mid);
+    return newme;
+}
+
+rb_method_entry_t *
+rb_method_entry_set(VALUE klass, ID mid, const rb_method_entry_t *me, rb_method_flag_t noex)
+{
+    return method_entry_set(klass, mid, me, noex, klass);
+}
+
+#define UNDEF_ALLOC_FUNC ((rb_alloc_func_t)-1)
+
+void
+rb_define_alloc_func(VALUE klass, VALUE (*func)(VALUE))
+{
+    Check_Type(klass, T_CLASS);
+    RCLASS_EXT(klass)->allocator = func;
+}
+
+void
+rb_undef_alloc_func(VALUE klass)
+{
+    rb_define_alloc_func(klass, UNDEF_ALLOC_FUNC);
+}
+
+rb_alloc_func_t
+rb_get_alloc_func(VALUE klass)
+{
+    Check_Type(klass, T_CLASS);
+
+    for (; klass; klass = RCLASS_SUPER(klass)) {
+	rb_alloc_func_t allocator = RCLASS_EXT(klass)->allocator;
+	if (allocator == UNDEF_ALLOC_FUNC) break;
+	if (allocator) return allocator;
+    }
+    return 0;
+}
+
+static inline rb_method_entry_t*
+search_method(VALUE klass, ID id, VALUE *defined_class_ptr)
+{
+    rb_method_entry_t *me;
+
+    for (me = 0; klass; klass = RCLASS_SUPER(klass)) {
+	if ((me = lookup_method_table(klass, id)) != 0) break;
+    }
+
+    if (defined_class_ptr)
+	*defined_class_ptr = klass;
+    return me;
+}
+
+rb_method_entry_t *
+rb_method_entry_at(VALUE klass, ID id)
+{
+    return lookup_method_table(klass, id);
+}
+
+/*
+ * search method entry without the method cache.
+ *
+ * if you need method entry with method cache (normal case), use
+ * rb_method_entry() simply.
+ */
+rb_method_entry_t *
+rb_method_entry_get_without_cache(VALUE klass, ID id,
+				  VALUE *defined_class_ptr)
+{
+    VALUE defined_class;
+    rb_method_entry_t *me = search_method(klass, id, &defined_class);
+
+    if (me && me->klass) {
+	switch (BUILTIN_TYPE(me->klass)) {
+	  case T_CLASS:
+	    if (RBASIC(klass)->flags & FL_SINGLETON) break;
+	    /* fall through */
+	  case T_ICLASS:
+	    defined_class = me->klass;
+	}
+    }
+
+    if (ruby_running) {
+	if (OPT_GLOBAL_METHOD_CACHE) {
+	    struct cache_entry *ent;
+	    ent = GLOBAL_METHOD_CACHE(klass, id);
+	    ent->class_serial = RCLASS_SERIAL(klass);
+	    ent->method_state = GET_GLOBAL_METHOD_STATE();
+	    ent->defined_class = defined_class;
+	    ent->mid = id;
+
+	    if (UNDEFINED_METHOD_ENTRY_P(me)) {
+		ent->me = 0;
+		me = 0;
+	    }
+	    else {
+		ent->me = me;
+	    }
+	}
+	else if (UNDEFINED_METHOD_ENTRY_P(me)) {
+	    me = 0;
+	}
+    }
+
+    if (defined_class_ptr)
+	*defined_class_ptr = defined_class;
+    return me;
+}
+
+#if VM_DEBUG_VERIFY_METHOD_CACHE
+static void
+verify_method_cache(VALUE klass, ID id, VALUE defined_class, rb_method_entry_t *me)
+{
+    VALUE actual_defined_class;
+    rb_method_entry_t *actual_me =
+	rb_method_entry_get_without_cache(klass, id, &actual_defined_class);
+
+    if (me != actual_me || defined_class != actual_defined_class) {
+	rb_bug("method cache verification failed");
+    }
+}
+#endif
+
+rb_method_entry_t *
+rb_method_entry(VALUE klass, ID id, VALUE *defined_class_ptr)
+{
+#if OPT_GLOBAL_METHOD_CACHE
+    struct cache_entry *ent;
+    ent = GLOBAL_METHOD_CACHE(klass, id);
+    if (ent->method_state == GET_GLOBAL_METHOD_STATE() &&
+	ent->class_serial == RCLASS_SERIAL(klass) &&
+	ent->mid == id) {
+	if (defined_class_ptr)
+	    *defined_class_ptr = ent->defined_class;
+#if VM_DEBUG_VERIFY_METHOD_CACHE
+	verify_method_cache(klass, id, ent->defined_class, ent->me);
+#endif
+	return ent->me;
+    }
+#endif
+
+    return rb_method_entry_get_without_cache(klass, id, defined_class_ptr);
+}
+
+static rb_method_entry_t *
+get_original_method_entry(VALUE refinements,
+			  const rb_method_entry_t *me,
+			  VALUE *defined_class_ptr)
+{
+    VALUE super;
+
+    if (me->def->body.orig_me) {
+	return me->def->body.orig_me;
+    }
+    else if (!(super = RCLASS_SUPER(me->klass))) {
+	return 0;
+    }
+    else {
+	rb_method_entry_t *tmp_me;
+	tmp_me = rb_method_entry(super, me->called_id,
+				 defined_class_ptr);
+	return rb_resolve_refined_method(refinements, tmp_me,
+					 defined_class_ptr);
+    }
+}
+
+rb_method_entry_t *
+rb_resolve_refined_method(VALUE refinements, const rb_method_entry_t *me,
+			  VALUE *defined_class_ptr)
+{
+    if (me && me->def->type == VM_METHOD_TYPE_REFINED) {
+	VALUE refinement;
+	rb_method_entry_t *tmp_me;
+
+	refinement = find_refinement(refinements, me->klass);
+	if (NIL_P(refinement)) {
+	    return get_original_method_entry(refinements, me,
+					     defined_class_ptr);
+	}
+	tmp_me = rb_method_entry(refinement, me->called_id,
+				 defined_class_ptr);
+	if (tmp_me && tmp_me->def->type != VM_METHOD_TYPE_REFINED) {
+	    return tmp_me;
+	}
+	else {
+	    return get_original_method_entry(refinements, me,
+					     defined_class_ptr);
+	}
+    }
+    else {
+	return (rb_method_entry_t *)me;
+    }
+}
+
+rb_method_entry_t *
+rb_method_entry_with_refinements(VALUE klass, ID id,
+				 VALUE *defined_class_ptr)
+{
+    VALUE defined_class;
+    rb_method_entry_t *me = rb_method_entry(klass, id, &defined_class);
+
+    if (me && me->def->type == VM_METHOD_TYPE_REFINED) {
+	NODE *cref = rb_vm_cref();
+	VALUE refinements = cref ? cref->nd_refinements : Qnil;
+
+	me = rb_resolve_refined_method(refinements, me, &defined_class);
+    }
+    if (defined_class_ptr)
+	*defined_class_ptr = defined_class;
+    return me;
+}
+
+rb_method_entry_t *
+rb_method_entry_without_refinements(VALUE klass, ID id,
+				    VALUE *defined_class_ptr)
+{
+    VALUE defined_class;
+    rb_method_entry_t *me = rb_method_entry(klass, id, &defined_class);
+
+    if (me && me->def->type == VM_METHOD_TYPE_REFINED) {
+	me = rb_resolve_refined_method(Qnil, me, &defined_class);
+    }
+    if (defined_class_ptr)
+	*defined_class_ptr = defined_class;
+    if (UNDEFINED_METHOD_ENTRY_P(me)) {
+	return 0;
+    }
+    else {
+	return me;
+    }
+}
+
+static void
+remove_method(VALUE klass, ID mid)
+{
+    st_data_t key, data;
+    rb_method_entry_t *me = 0;
+    VALUE self = klass;
+
+    klass = RCLASS_ORIGIN(klass);
+    rb_frozen_class_p(klass);
+    if (mid == object_id || mid == id__send__ || mid == idInitialize) {
+	rb_warn("removing `%s' may cause serious problems", rb_id2name(mid));
+    }
+
+    if (!st_lookup(RCLASS_M_TBL(klass), mid, &data) ||
+	!(me = (rb_method_entry_t *)data) ||
+	(!me->def || me->def->type == VM_METHOD_TYPE_UNDEF) ||
+        UNDEFINED_REFINED_METHOD_P(me->def)) {
+	rb_name_error(mid, "method `%"PRIsVALUE"' not defined in %"PRIsVALUE,
+		      rb_id2str(mid), rb_class_path(klass));
+    }
+
+    key = (st_data_t)mid;
+    st_delete(RCLASS_M_TBL(klass), &key, &data);
+
+    rb_vm_check_redefinition_opt_method(me, klass);
+    rb_clear_method_cache_by_class(klass);
+    rb_unlink_method_entry(me);
+
+    if (me->def->type == VM_METHOD_TYPE_REFINED) {
+	rb_add_refined_method_entry(klass, mid);
+    }
+
+    CALL_METHOD_HOOK(self, removed, mid);
+}
+
+void
+rb_remove_method_id(VALUE klass, ID mid)
+{
+    remove_method(klass, mid);
+}
+
+void
+rb_remove_method(VALUE klass, const char *name)
+{
+    remove_method(klass, rb_intern(name));
+}
+
+/*
+ *  call-seq:
+ *     remove_method(symbol)   -> self
+ *     remove_method(string)   -> self
+ *
+ *  Removes the method identified by _symbol_ from the current
+ *  class. For an example, see <code>Module.undef_method</code>.
+ *  String arguments are converted to symbols.
+ */
+
+static VALUE
+rb_mod_remove_method(int argc, VALUE *argv, VALUE mod)
+{
+    int i;
+
+    for (i = 0; i < argc; i++) {
+	VALUE v = argv[i];
+	ID id = rb_check_id(&v);
+	if (!id) {
+	    rb_name_error_str(v, "method `%"PRIsVALUE"' not defined in %"PRIsVALUE,
+			      v, rb_obj_class(mod));
+	}
+	remove_method(mod, id);
+    }
+    return mod;
+}
+
+static void
+rb_export_method(VALUE klass, ID name, rb_method_flag_t noex)
+{
+    rb_method_entry_t *me;
+    VALUE defined_class;
+
+    me = search_method(klass, name, &defined_class);
+    if (!me && RB_TYPE_P(klass, T_MODULE)) {
+	me = search_method(rb_cObject, name, &defined_class);
+    }
+
+    if (UNDEFINED_METHOD_ENTRY_P(me) ||
+	UNDEFINED_REFINED_METHOD_P(me->def)) {
+	rb_print_undef(klass, name, 0);
+    }
+
+    if (me->flag != noex) {
+	rb_vm_check_redefinition_opt_method(me, klass);
+
+	if (klass == defined_class ||
+	    RCLASS_ORIGIN(klass) == defined_class) {
+	    me->flag = noex;
+	    if (me->def->type == VM_METHOD_TYPE_REFINED) {
+		me->def->body.orig_me->flag = noex;
+	    }
+	    rb_clear_method_cache_by_class(klass);
+	}
+	else {
+	    rb_add_method(klass, name, VM_METHOD_TYPE_ZSUPER, 0, noex);
+	}
+    }
+}
+
+int
+rb_method_boundp(VALUE klass, ID id, int ex)
+{
+    rb_method_entry_t *me =
+	rb_method_entry_without_refinements(klass, id, 0);
+
+    if (me != 0) {
+	if ((ex & ~NOEX_RESPONDS) &&
+	    ((me->flag & NOEX_PRIVATE) ||
+	     ((ex & NOEX_RESPONDS) && (me->flag & NOEX_PROTECTED)))) {
+	    return 0;
+	}
+	if (!me->def) return 0;
+	if (me->def->type == VM_METHOD_TYPE_NOTIMPLEMENTED) {
+	    if (ex & NOEX_RESPONDS) return 2;
+	    return 0;
+	}
+	return 1;
+    }
+    return 0;
+}
+
+extern ID rb_check_attr_id(ID id);
+
+void
+rb_attr(VALUE klass, ID id, int read, int write, int ex)
+{
+    VALUE attriv;
+    VALUE aname;
+    rb_method_flag_t noex;
+
+    if (!ex) {
+	noex = NOEX_PUBLIC;
+    }
+    else {
+	if (SCOPE_TEST(NOEX_PRIVATE)) {
+	    noex = NOEX_PRIVATE;
+	    rb_warning((SCOPE_CHECK(NOEX_MODFUNC)) ?
+		       "attribute accessor as module_function" :
+		       "private attribute?");
+	}
+	else if (SCOPE_TEST(NOEX_PROTECTED)) {
+	    noex = NOEX_PROTECTED;
+	}
+	else {
+	    noex = NOEX_PUBLIC;
+	}
+    }
+
+    aname = rb_id2str(rb_check_attr_id(id));
+    if (NIL_P(aname)) {
+	rb_raise(rb_eArgError, "argument needs to be symbol or string");
+    }
+    attriv = (VALUE)rb_intern_str(rb_sprintf("@%"PRIsVALUE, aname));
+    if (read) {
+	rb_add_method(klass, id, VM_METHOD_TYPE_IVAR, (void *)attriv, noex);
+    }
+    if (write) {
+	rb_add_method(klass, rb_id_attrset(id), VM_METHOD_TYPE_ATTRSET, (void *)attriv, noex);
+    }
+}
+
+void
+rb_undef(VALUE klass, ID id)
+{
+    rb_method_entry_t *me;
+
+    if (NIL_P(klass)) {
+	rb_raise(rb_eTypeError, "no class to undef method");
+    }
+    rb_frozen_class_p(klass);
+    if (id == object_id || id == id__send__ || id == idInitialize) {
+	rb_warn("undefining `%s' may cause serious problems", rb_id2name(id));
+    }
+
+    me = search_method(klass, id, 0);
+
+    if (UNDEFINED_METHOD_ENTRY_P(me) ||
+	UNDEFINED_REFINED_METHOD_P(me->def)) {
+	const char *s0 = " class";
+	VALUE c = klass;
+
+	if (FL_TEST(c, FL_SINGLETON)) {
+	    VALUE obj = rb_ivar_get(klass, attached);
+
+	    if (RB_TYPE_P(obj, T_MODULE) || RB_TYPE_P(obj, T_CLASS)) {
+		c = obj;
+		s0 = "";
+	    }
+	}
+	else if (RB_TYPE_P(c, T_MODULE)) {
+	    s0 = " module";
+	}
+	rb_name_error(id, "undefined method `%"PRIsVALUE"' for%s `%"PRIsVALUE"'",
+		      QUOTE_ID(id), s0, rb_class_name(c));
+    }
+
+    rb_add_method(klass, id, VM_METHOD_TYPE_UNDEF, 0, NOEX_PUBLIC);
+
+    CALL_METHOD_HOOK(klass, undefined, id);
+}
+
+/*
+ *  call-seq:
+ *     undef_method(symbol)    -> self
+ *     undef_method(string)    -> self
+ *
+ *  Prevents the current class from responding to calls to the named
+ *  method. Contrast this with <code>remove_method</code>, which deletes
+ *  the method from the particular class; Ruby will still search
+ *  superclasses and mixed-in modules for a possible receiver.
+ *  String arguments are converted to symbols.
+ *
+ *     class Parent
+ *       def hello
+ *         puts "In parent"
+ *       end
+ *     end
+ *     class Child < Parent
+ *       def hello
+ *         puts "In child"
+ *       end
+ *     end
+ *
+ *
+ *     c = Child.new
+ *     c.hello
+ *
+ *
+ *     class Child
+ *       remove_method :hello  # remove from child, still in parent
+ *     end
+ *     c.hello
+ *
+ *
+ *     class Child
+ *       undef_method :hello   # prevent any calls to 'hello'
+ *     end
+ *     c.hello
+ *
+ *  <em>produces:</em>
+ *
+ *     In child
+ *     In parent
+ *     prog.rb:23: undefined method `hello' for #<Child:0x401b3bb4> (NoMethodError)
+ */
+
+static VALUE
+rb_mod_undef_method(int argc, VALUE *argv, VALUE mod)
+{
+    int i;
+    for (i = 0; i < argc; i++) {
+	VALUE v = argv[i];
+	ID id = rb_check_id(&v);
+	if (!id) {
+	    rb_method_name_error(mod, v);
+	}
+	rb_undef(mod, id);
+    }
+    return mod;
+}
+
+/*
+ *  call-seq:
+ *     mod.method_defined?(symbol)    -> true or false
+ *     mod.method_defined?(string)    -> true or false
+ *
+ *  Returns +true+ if the named method is defined by
+ *  _mod_ (or its included modules and, if _mod_ is a class,
+ *  its ancestors). Public and protected methods are matched.
+ *  String arguments are converted to symbols.
+ *
+ *     module A
+ *       def method1()  end
+ *     end
+ *     class B
+ *       def method2()  end
+ *     end
+ *     class C < B
+ *       include A
+ *       def method3()  end
+ *     end
+ *
+ *     A.method_defined? :method1    #=> true
+ *     C.method_defined? "method1"   #=> true
+ *     C.method_defined? "method2"   #=> true
+ *     C.method_defined? "method3"   #=> true
+ *     C.method_defined? "method4"   #=> false
+ */
+
+static VALUE
+rb_mod_method_defined(VALUE mod, VALUE mid)
+{
+    ID id = rb_check_id(&mid);
+    if (!id || !rb_method_boundp(mod, id, 1)) {
+	return Qfalse;
+    }
+    return Qtrue;
+
+}
+
+#define VISI_CHECK(x,f) (((x)&NOEX_MASK) == (f))
+
+static VALUE
+check_definition(VALUE mod, VALUE mid, rb_method_flag_t noex)
+{
+    const rb_method_entry_t *me;
+    ID id = rb_check_id(&mid);
+    if (!id) return Qfalse;
+    me = rb_method_entry_without_refinements(mod, id, 0);
+    if (me) {
+	if (VISI_CHECK(me->flag, noex))
+	    return Qtrue;
+    }
+    return Qfalse;
+}
+
+/*
+ *  call-seq:
+ *     mod.public_method_defined?(symbol)   -> true or false
+ *     mod.public_method_defined?(string)   -> true or false
+ *
+ *  Returns +true+ if the named public method is defined by
+ *  _mod_ (or its included modules and, if _mod_ is a class,
+ *  its ancestors).
+ *  String arguments are converted to symbols.
+ *
+ *     module A
+ *       def method1()  end
+ *     end
+ *     class B
+ *       protected
+ *       def method2()  end
+ *     end
+ *     class C < B
+ *       include A
+ *       def method3()  end
+ *     end
+ *
+ *     A.method_defined? :method1           #=> true
+ *     C.public_method_defined? "method1"   #=> true
+ *     C.public_method_defined? "method2"   #=> false
+ *     C.method_defined? "method2"          #=> true
+ */
+
+static VALUE
+rb_mod_public_method_defined(VALUE mod, VALUE mid)
+{
+    return check_definition(mod, mid, NOEX_PUBLIC);
+}
+
+/*
+ *  call-seq:
+ *     mod.private_method_defined?(symbol)    -> true or false
+ *     mod.private_method_defined?(string)    -> true or false
+ *
+ *  Returns +true+ if the named private method is defined by
+ *  _ mod_ (or its included modules and, if _mod_ is a class,
+ *  its ancestors).
+ *  String arguments are converted to symbols.
+ *
+ *     module A
+ *       def method1()  end
+ *     end
+ *     class B
+ *       private
+ *       def method2()  end
+ *     end
+ *     class C < B
+ *       include A
+ *       def method3()  end
+ *     end
+ *
+ *     A.method_defined? :method1            #=> true
+ *     C.private_method_defined? "method1"   #=> false
+ *     C.private_method_defined? "method2"   #=> true
+ *     C.method_defined? "method2"           #=> false
+ */
+
+static VALUE
+rb_mod_private_method_defined(VALUE mod, VALUE mid)
+{
+    return check_definition(mod, mid, NOEX_PRIVATE);
+}
+
+/*
+ *  call-seq:
+ *     mod.protected_method_defined?(symbol)   -> true or false
+ *     mod.protected_method_defined?(string)   -> true or false
+ *
+ *  Returns +true+ if the named protected method is defined
+ *  by _mod_ (or its included modules and, if _mod_ is a
+ *  class, its ancestors).
+ *  String arguments are converted to symbols.
+ *
+ *     module A
+ *       def method1()  end
+ *     end
+ *     class B
+ *       protected
+ *       def method2()  end
+ *     end
+ *     class C < B
+ *       include A
+ *       def method3()  end
+ *     end
+ *
+ *     A.method_defined? :method1              #=> true
+ *     C.protected_method_defined? "method1"   #=> false
+ *     C.protected_method_defined? "method2"   #=> true
+ *     C.method_defined? "method2"             #=> true
+ */
+
+static VALUE
+rb_mod_protected_method_defined(VALUE mod, VALUE mid)
+{
+    return check_definition(mod, mid, NOEX_PROTECTED);
+}
+
+int
+rb_method_entry_eq(const rb_method_entry_t *m1, const rb_method_entry_t *m2)
+{
+    return rb_method_definition_eq(m1->def, m2->def);
+}
+
+static int
+rb_method_definition_eq(const rb_method_definition_t *d1, const rb_method_definition_t *d2)
+{
+    if (d1 && d1->type == VM_METHOD_TYPE_REFINED && d1->body.orig_me)
+	d1 = d1->body.orig_me->def;
+    if (d2 && d2->type == VM_METHOD_TYPE_REFINED && d2->body.orig_me)
+	d2 = d2->body.orig_me->def;
+    if (d1 == d2) return 1;
+    if (!d1 || !d2) return 0;
+    if (d1->type != d2->type) {
+	return 0;
+    }
+    switch (d1->type) {
+      case VM_METHOD_TYPE_ISEQ:
+	return d1->body.iseq == d2->body.iseq;
+      case VM_METHOD_TYPE_CFUNC:
+	return
+	  d1->body.cfunc.func == d2->body.cfunc.func &&
+	  d1->body.cfunc.argc == d2->body.cfunc.argc;
+      case VM_METHOD_TYPE_ATTRSET:
+      case VM_METHOD_TYPE_IVAR:
+	return d1->body.attr.id == d2->body.attr.id;
+      case VM_METHOD_TYPE_BMETHOD:
+	return RTEST(rb_equal(d1->body.proc, d2->body.proc));
+      case VM_METHOD_TYPE_MISSING:
+	return d1->original_id == d2->original_id;
+      case VM_METHOD_TYPE_ZSUPER:
+      case VM_METHOD_TYPE_NOTIMPLEMENTED:
+      case VM_METHOD_TYPE_UNDEF:
+	return 1;
+      case VM_METHOD_TYPE_OPTIMIZED:
+	return d1->body.optimize_type == d2->body.optimize_type;
+      default:
+	rb_bug("rb_method_entry_eq: unsupported method type (%d)\n", d1->type);
+	return 0;
+    }
+}
+
+static st_index_t
+rb_hash_method_definition(st_index_t hash, const rb_method_definition_t *def)
+{
+  again:
+    hash = rb_hash_uint(hash, def->type);
+    switch (def->type) {
+      case VM_METHOD_TYPE_ISEQ:
+	return rb_hash_uint(hash, (st_index_t)def->body.iseq);
+      case VM_METHOD_TYPE_CFUNC:
+	hash = rb_hash_uint(hash, (st_index_t)def->body.cfunc.func);
+	return rb_hash_uint(hash, def->body.cfunc.argc);
+      case VM_METHOD_TYPE_ATTRSET:
+      case VM_METHOD_TYPE_IVAR:
+	return rb_hash_uint(hash, def->body.attr.id);
+      case VM_METHOD_TYPE_BMETHOD:
+	return rb_hash_proc(hash, def->body.proc);
+      case VM_METHOD_TYPE_MISSING:
+	return rb_hash_uint(hash, def->original_id);
+      case VM_METHOD_TYPE_ZSUPER:
+      case VM_METHOD_TYPE_NOTIMPLEMENTED:
+      case VM_METHOD_TYPE_UNDEF:
+	return hash;
+      case VM_METHOD_TYPE_OPTIMIZED:
+	return rb_hash_uint(hash, def->body.optimize_type);
+      case VM_METHOD_TYPE_REFINED:
+	if (def->body.orig_me) {
+	    def = def->body.orig_me->def;
+	    goto again;
+	}
+	else {
+	    return hash;
+	}
+      default:
+	rb_bug("rb_hash_method_definition: unsupported method type (%d)\n", def->type);
+    }
+    return hash;
+}
+
+st_index_t
+rb_hash_method_entry(st_index_t hash, const rb_method_entry_t *me)
+{
+    return rb_hash_method_definition(hash, me->def);
+}
+
+void
+rb_alias(VALUE klass, ID name, ID def)
+{
+    VALUE target_klass = klass;
+    VALUE defined_class;
+    rb_method_entry_t *orig_me;
+    rb_method_flag_t flag = NOEX_UNDEF;
+
+    if (NIL_P(klass)) {
+	rb_raise(rb_eTypeError, "no class to make alias");
+    }
+
+    rb_frozen_class_p(klass);
+
+  again:
+    orig_me = search_method(klass, def, &defined_class);
+
+    if (UNDEFINED_METHOD_ENTRY_P(orig_me) ||
+	UNDEFINED_REFINED_METHOD_P(orig_me->def)) {
+	if ((!RB_TYPE_P(klass, T_MODULE)) ||
+	    (orig_me = search_method(rb_cObject, def, 0),
+	     UNDEFINED_METHOD_ENTRY_P(orig_me))) {
+	    rb_print_undef(klass, def, 0);
+	}
+    }
+    if (orig_me->def->type == VM_METHOD_TYPE_ZSUPER) {
+	klass = RCLASS_SUPER(klass);
+	def = orig_me->def->original_id;
+	flag = orig_me->flag;
+	goto again;
+    }
+    if (RB_TYPE_P(defined_class, T_ICLASS)) {
+	VALUE real_class = RBASIC_CLASS(defined_class);
+	if (real_class && RCLASS_ORIGIN(real_class) == defined_class)
+	    defined_class = real_class;
+    }
+
+    if (flag == NOEX_UNDEF) flag = orig_me->flag;
+    method_entry_set(target_klass, name, orig_me, flag, defined_class);
+}
+
+/*
+ *  call-seq:
+ *     alias_method(new_name, old_name)   -> self
+ *
+ *  Makes <i>new_name</i> a new copy of the method <i>old_name</i>. This can
+ *  be used to retain access to methods that are overridden.
+ *
+ *     module Mod
+ *       alias_method :orig_exit, :exit
+ *       def exit(code=0)
+ *         puts "Exiting with code #{code}"
+ *         orig_exit(code)
+ *       end
+ *     end
+ *     include Mod
+ *     exit(99)
+ *
+ *  <em>produces:</em>
+ *
+ *     Exiting with code 99
+ */
+
+static VALUE
+rb_mod_alias_method(VALUE mod, VALUE newname, VALUE oldname)
+{
+    ID oldid = rb_check_id(&oldname);
+    if (!oldid) {
+	rb_print_undef_str(mod, oldname);
+    }
+    rb_alias(mod, rb_to_id(newname), oldid);
+    return mod;
+}
+
+static void
+set_method_visibility(VALUE self, int argc, const VALUE *argv, rb_method_flag_t ex)
+{
+    int i;
+
+    if (argc == 0) {
+	rb_warning("%"PRIsVALUE" with no argument is just ignored",
+		   QUOTE_ID(rb_frame_callee()));
+	return;
+    }
+
+    for (i = 0; i < argc; i++) {
+	VALUE v = argv[i];
+	ID id = rb_check_id(&v);
+	if (!id) {
+	    rb_print_undef_str(self, v);
+	}
+	rb_export_method(self, id, ex);
+    }
+}
+
+static VALUE
+set_visibility(int argc, const VALUE *argv, VALUE module, rb_method_flag_t ex)
+{
+    if (argc == 0) {
+	SCOPE_SET(ex);
+    }
+    else {
+	set_method_visibility(module, argc, argv, ex);
+    }
+    return module;
+}
+
+/*
+ *  call-seq:
+ *     public                 -> self
+ *     public(symbol, ...)    -> self
+ *     public(string, ...)    -> self
+ *
+ *  With no arguments, sets the default visibility for subsequently
+ *  defined methods to public. With arguments, sets the named methods to
+ *  have public visibility.
+ *  String arguments are converted to symbols.
+ */
+
+static VALUE
+rb_mod_public(int argc, VALUE *argv, VALUE module)
+{
+    return set_visibility(argc, argv, module, NOEX_PUBLIC);
+}
+
+/*
+ *  call-seq:
+ *     protected                -> self
+ *     protected(symbol, ...)   -> self
+ *     protected(string, ...)   -> self
+ *
+ *  With no arguments, sets the default visibility for subsequently
+ *  defined methods to protected. With arguments, sets the named methods
+ *  to have protected visibility.
+ *  String arguments are converted to symbols.
+ */
+
+static VALUE
+rb_mod_protected(int argc, VALUE *argv, VALUE module)
+{
+    return set_visibility(argc, argv, module, NOEX_PROTECTED);
+}
+
+/*
+ *  call-seq:
+ *     private                 -> self
+ *     private(symbol, ...)    -> self
+ *     private(string, ...)    -> self
+ *
+ *  With no arguments, sets the default visibility for subsequently
+ *  defined methods to private. With arguments, sets the named methods
+ *  to have private visibility.
+ *  String arguments are converted to symbols.
+ *
+ *     module Mod
+ *       def a()  end
+ *       def b()  end
+ *       private
+ *       def c()  end
+ *       private :a
+ *     end
+ *     Mod.private_instance_methods   #=> [:a, :c]
+ */
+
+static VALUE
+rb_mod_private(int argc, VALUE *argv, VALUE module)
+{
+    return set_visibility(argc, argv, module, NOEX_PRIVATE);
+}
+
+/*
+ *  call-seq:
+ *     mod.public_class_method(symbol, ...)    -> mod
+ *     mod.public_class_method(string, ...)    -> mod
+ *
+ *  Makes a list of existing class methods public.
+ *
+ *  String arguments are converted to symbols.
+ */
+
+static VALUE
+rb_mod_public_method(int argc, VALUE *argv, VALUE obj)
+{
+    set_method_visibility(rb_singleton_class(obj), argc, argv, NOEX_PUBLIC);
+    return obj;
+}
+
+/*
+ *  call-seq:
+ *     mod.private_class_method(symbol, ...)   -> mod
+ *     mod.private_class_method(string, ...)   -> mod
+ *
+ *  Makes existing class methods private. Often used to hide the default
+ *  constructor <code>new</code>.
+ *
+ *  String arguments are converted to symbols.
+ *
+ *     class SimpleSingleton  # Not thread safe
+ *       private_class_method :new
+ *       def SimpleSingleton.create(*args, &block)
+ *         @me = new(*args, &block) if ! @me
+ *         @me
+ *       end
+ *     end
+ */
+
+static VALUE
+rb_mod_private_method(int argc, VALUE *argv, VALUE obj)
+{
+    set_method_visibility(rb_singleton_class(obj), argc, argv, NOEX_PRIVATE);
+    return obj;
+}
+
+/*
+ *  call-seq:
+ *     public
+ *     public(symbol, ...)
+ *     public(string, ...)
+ *
+ *  With no arguments, sets the default visibility for subsequently
+ *  defined methods to public. With arguments, sets the named methods to
+ *  have public visibility.
+ *
+ *  String arguments are converted to symbols.
+ */
+
+static VALUE
+top_public(int argc, VALUE *argv)
+{
+    return rb_mod_public(argc, argv, rb_cObject);
+}
+
+/*
+ *  call-seq:
+ *     private
+ *     private(symbol, ...)
+ *     private(string, ...)
+ *
+ *  With no arguments, sets the default visibility for subsequently
+ *  defined methods to private. With arguments, sets the named methods to
+ *  have private visibility.
+ *
+ *  String arguments are converted to symbols.
+ */
+static VALUE
+top_private(int argc, VALUE *argv)
+{
+    return rb_mod_private(argc, argv, rb_cObject);
+}
+
+/*
+ *  call-seq:
+ *     module_function(symbol, ...)    -> self
+ *     module_function(string, ...)    -> self
+ *
+ *  Creates module functions for the named methods. These functions may
+ *  be called with the module as a receiver, and also become available
+ *  as instance methods to classes that mix in the module. Module
+ *  functions are copies of the original, and so may be changed
+ *  independently. The instance-method versions are made private. If
+ *  used with no arguments, subsequently defined methods become module
+ *  functions.
+ *  String arguments are converted to symbols.
+ *
+ *     module Mod
+ *       def one
+ *         "This is one"
+ *       end
+ *       module_function :one
+ *     end
+ *     class Cls
+ *       include Mod
+ *       def call_one
+ *         one
+ *       end
+ *     end
+ *     Mod.one     #=> "This is one"
+ *     c = Cls.new
+ *     c.call_one  #=> "This is one"
+ *     module Mod
+ *       def one
+ *         "This is the new one"
+ *       end
+ *     end
+ *     Mod.one     #=> "This is one"
+ *     c.call_one  #=> "This is the new one"
+ */
+
+static VALUE
+rb_mod_modfunc(int argc, VALUE *argv, VALUE module)
+{
+    int i;
+    ID id;
+    const rb_method_entry_t *me;
+
+    if (!RB_TYPE_P(module, T_MODULE)) {
+	rb_raise(rb_eTypeError, "module_function must be called for modules");
+    }
+
+    if (argc == 0) {
+	SCOPE_SET(NOEX_MODFUNC);
+	return module;
+    }
+
+    set_method_visibility(module, argc, argv, NOEX_PRIVATE);
+
+    for (i = 0; i < argc; i++) {
+	VALUE m = module;
+
+	id = rb_to_id(argv[i]);
+	for (;;) {
+	    me = search_method(m, id, 0);
+	    if (me == 0) {
+		me = search_method(rb_cObject, id, 0);
+	    }
+	    if (UNDEFINED_METHOD_ENTRY_P(me)) {
+		rb_print_undef(module, id, 0);
+	    }
+	    if (me->def->type != VM_METHOD_TYPE_ZSUPER) {
+		break; /* normal case: need not to follow 'super' link */
+	    }
+	    m = RCLASS_SUPER(m);
+	    if (!m)
+		break;
+	}
+	rb_method_entry_set(rb_singleton_class(module), id, me, NOEX_PUBLIC);
+    }
+    return module;
+}
+
+int
+rb_method_basic_definition_p(VALUE klass, ID id)
+{
+    const rb_method_entry_t *me = rb_method_entry(klass, id, 0);
+    if (me && (me->flag & NOEX_BASIC))
+	return 1;
+    return 0;
+}
+
+static inline int
+basic_obj_respond_to(VALUE obj, ID id, int pub)
+{
+    VALUE klass = CLASS_OF(obj);
+    VALUE args[2];
+
+    switch (rb_method_boundp(klass, id, pub|NOEX_RESPONDS)) {
+      case 2:
+	return FALSE;
+      case 0:
+	args[0] = ID2SYM(id);
+	args[1] = pub ? Qfalse : Qtrue;
+	return RTEST(rb_funcall2(obj, idRespond_to_missing, 2, args));
+      default:
+	return TRUE;
+    }
+}
+
+int
+rb_obj_respond_to(VALUE obj, ID id, int priv)
+{
+    VALUE klass = CLASS_OF(obj);
+
+    if (rb_method_basic_definition_p(klass, idRespond_to)) {
+	return basic_obj_respond_to(obj, id, !priv);
+    }
+    else {
+	int argc = 1;
+	VALUE args[2];
+	args[0] = ID2SYM(id);
+	args[1] = Qtrue;
+	if (priv) {
+	    if (rb_obj_method_arity(obj, idRespond_to) != 1) {
+		argc = 2;
+	    }
+	    else if (!NIL_P(ruby_verbose)) {
+		VALUE klass = CLASS_OF(obj);
+		VALUE location = rb_mod_method_location(klass, idRespond_to);
+		rb_warn("%"PRIsVALUE"%c""respond_to?(:%"PRIsVALUE") is"
+			" old fashion which takes only one parameter",
+			(FL_TEST(klass, FL_SINGLETON) ? obj : klass),
+			(FL_TEST(klass, FL_SINGLETON) ? '.' : '#'),
+			QUOTE_ID(id));
+		if (!NIL_P(location)) {
+		    VALUE path = RARRAY_AREF(location, 0);
+		    VALUE line = RARRAY_AREF(location, 1);
+		    if (!NIL_P(path)) {
+			rb_compile_warn(RSTRING_PTR(path), NUM2INT(line),
+					"respond_to? is defined here");
+		    }
+		}
+	    }
+	}
+	return RTEST(rb_funcall2(obj, idRespond_to, argc,  args));
+    }
+}
+
+int
+rb_respond_to(VALUE obj, ID id)
+{
+    return rb_obj_respond_to(obj, id, FALSE);
+}
+
+
+/*
+ *  call-seq:
+ *     obj.respond_to?(symbol, include_all=false) -> true or false
+ *     obj.respond_to?(string, include_all=false) -> true or false
+ *
+ *  Returns +true+ if _obj_ responds to the given method.  Private and
+ *  protected methods are included in the search only if the optional
+ *  second parameter evaluates to +true+.
+ *
+ *  If the method is not implemented,
+ *  as Process.fork on Windows, File.lchmod on GNU/Linux, etc.,
+ *  false is returned.
+ *
+ *  If the method is not defined, <code>respond_to_missing?</code>
+ *  method is called and the result is returned.
+ *
+ *  When the method name parameter is given as a string, the string is
+ *  converted to a symbol.
+ */
+
+static VALUE
+obj_respond_to(int argc, VALUE *argv, VALUE obj)
+{
+    VALUE mid, priv;
+    ID id;
+
+    rb_scan_args(argc, argv, "11", &mid, &priv);
+    if (!(id = rb_check_id(&mid))) {
+	if (!rb_method_basic_definition_p(CLASS_OF(obj), idRespond_to_missing)) {
+	    VALUE args[2];
+	    args[0] = rb_to_symbol(mid);
+	    args[1] = priv;
+	    return rb_funcall2(obj, idRespond_to_missing, 2, args);
+	}
+	return Qfalse;
+    }
+    if (basic_obj_respond_to(obj, id, !RTEST(priv)))
+	return Qtrue;
+    return Qfalse;
+}
+
+/*
+ *  call-seq:
+ *     obj.respond_to_missing?(symbol, include_all) -> true or false
+ *     obj.respond_to_missing?(string, include_all) -> true or false
+ *
+ *  DO NOT USE THIS DIRECTLY.
+ *
+ *  Hook method to return whether the _obj_ can respond to _id_ method
+ *  or not.
+ *
+ *  When the method name parameter is given as a string, the string is
+ *  converted to a symbol.
+ *
+ *  See #respond_to?, and the example of BasicObject.
+ */
+static VALUE
+obj_respond_to_missing(VALUE obj, VALUE mid, VALUE priv)
+{
+    return Qfalse;
+}
+
+void
+Init_Method(void)
+{
+#if OPT_GLOBAL_METHOD_CACHE
+    char *ptr = getenv("RUBY_GLOBAL_METHOD_CACHE_SIZE");
+    int val;
+
+    if (ptr != NULL && (val = atoi(ptr)) > 0) {
+	if ((val & (val - 1)) == 0) { /* ensure val is a power of 2 */
+	    global_method_cache.size = val;
+	    global_method_cache.mask = val - 1;
+	}
+	else {
+	   fprintf(stderr, "RUBY_GLOBAL_METHOD_CACHE_SIZE was set to %d but ignored because the value is not a power of 2.\n", val);
+	}
+    }
+
+    global_method_cache.entries = (struct cache_entry *)calloc(global_method_cache.size, sizeof(struct cache_entry));
+    if (global_method_cache.entries == NULL) {
+	fprintf(stderr, "[FATAL] failed to allocate memory\n");
+	exit(EXIT_FAILURE);
+    }
+#endif
+}
+
+void
+Init_eval_method(void)
+{
+#undef rb_intern
+#define rb_intern(str) rb_intern_const(str)
+
+    rb_define_method(rb_mKernel, "respond_to?", obj_respond_to, -1);
+    rb_define_method(rb_mKernel, "respond_to_missing?", obj_respond_to_missing, 2);
+
+    rb_define_private_method(rb_cModule, "remove_method", rb_mod_remove_method, -1);
+    rb_define_private_method(rb_cModule, "undef_method", rb_mod_undef_method, -1);
+    rb_define_private_method(rb_cModule, "alias_method", rb_mod_alias_method, 2);
+    rb_define_private_method(rb_cModule, "public", rb_mod_public, -1);
+    rb_define_private_method(rb_cModule, "protected", rb_mod_protected, -1);
+    rb_define_private_method(rb_cModule, "private", rb_mod_private, -1);
+    rb_define_private_method(rb_cModule, "module_function", rb_mod_modfunc, -1);
+
+    rb_define_method(rb_cModule, "method_defined?", rb_mod_method_defined, 1);
+    rb_define_method(rb_cModule, "public_method_defined?", rb_mod_public_method_defined, 1);
+    rb_define_method(rb_cModule, "private_method_defined?", rb_mod_private_method_defined, 1);
+    rb_define_method(rb_cModule, "protected_method_defined?", rb_mod_protected_method_defined, 1);
+    rb_define_method(rb_cModule, "public_class_method", rb_mod_public_method, -1);
+    rb_define_method(rb_cModule, "private_class_method", rb_mod_private_method, -1);
+
+    rb_define_private_method(rb_singleton_class(rb_vm_top_self()),
+			     "public", top_public, -1);
+    rb_define_private_method(rb_singleton_class(rb_vm_top_self()),
+			     "private", top_private, -1);
+
+    {
+#define REPLICATE_METHOD(klass, id, noex) \
+	rb_method_entry_set((klass), (id), \
+			    rb_method_entry((klass), (id), 0), \
+			    (rb_method_flag_t)(noex | NOEX_BASIC | NOEX_NOREDEF))
+	REPLICATE_METHOD(rb_eException, idMethodMissing, NOEX_PRIVATE);
+	REPLICATE_METHOD(rb_eException, idRespond_to, NOEX_PUBLIC);
+	REPLICATE_METHOD(rb_eException, idRespond_to_missing, NOEX_PUBLIC);
+    }
+}