* parse.y (rb_compose_ivar2): function to create a new ivar2

  symbol from a symbol and a class.  back-ported from matzruby.

* parse.y (rb_decompose_ivar2): reverse function of
  rb_compose_ivar2(). 

* marshal.c (w_symbol): support class local instance variables.

* marshal.c (r_object0): ditto.

* compile.c (defined_expr): ditto.

* compile.c (iseq_compile_each): ditto.

* insns.def: add two new instructions: getinstancevariable2 and
  setinstancevariable2.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@11630 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

13 files changed, 281 insertions, 27 deletions

diff --git a/ChangeLog b/ChangeLog
index 5cea64c200..ec4e9acdce 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,25 @@ Sun Feb  4 02:22:59 2007  Akinori MUSHA  <knu@iDaemons.org>
 	* lib/cgi.rb (CGI::QueryExtension::read_multipart): Remove a debug
 	  print.
 
+Sat Feb  3 23:51:58 2007  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* parse.y (rb_compose_ivar2): function to create a new ivar2
+	  symbol from a symbol and a class.  back-ported from matzruby.
+
+	* parse.y (rb_decompose_ivar2): reverse function of
+	  rb_compose_ivar2(). 
+
+	* marshal.c (w_symbol): support class local instance variables.
+
+	* marshal.c (r_object0): ditto.
+
+	* compile.c (defined_expr): ditto.
+
+	* compile.c (iseq_compile_each): ditto.
+
+	* insns.def: add two new instructions: getinstancevariable2 and
+	  setinstancevariable2.
+
 Sat Feb  3 23:21:13 2007  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* insns.def (setclassvariable): remove unnecessary operand.
diff --git a/compile.c b/compile.c
index 5455bd7034..54a806ed99 100644
--- a/compile.c
+++ b/compile.c
@@ -2345,6 +2345,11 @@ defined_expr(yarv_iseq_t *iseq, LINK_ANCHOR *ret,
 	ADD_INSN3(ret, nd_line(node), defined, INT2FIX(DEFINED_IVAR),
 		  ID2SYM(node->nd_vid), needstr);
 	return 1;
+      case NODE_IVAR2:
+	ADD_INSN(ret, nd_line(node), putnil);
+	ADD_INSN3(ret, nd_line(node), defined, INT2FIX(DEFINED_IVAR2),
+		  ID2SYM(node->nd_vid), needstr);
+	return 1;
 
       case NODE_GVAR:
 	ADD_INSN(ret, nd_line(node), putnil);
@@ -3327,6 +3332,15 @@ iseq_compile_each(yarv_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)
 		    ID2SYM(node->nd_vid));
 	  break;
       }
+      case NODE_IASGN2:{
+	  COMPILE(ret, "lvalue", node->nd_value);
+	  if (!poped) {
+	      ADD_INSN(ret, nd_line(node), dup);
+	  }
+	  ADD_INSN1(ret, nd_line(node), setinstancevariable2,
+		    ID2SYM(node->nd_vid));
+	  break;
+      }
       case NODE_CDECL:{
 	  COMPILE(ret, "lvalue", node->nd_value);
 
@@ -3903,6 +3917,14 @@ iseq_compile_each(yarv_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)
 	  }
 	  break;
       }
+      case NODE_IVAR2:{
+	  debugi("nd_vid", node->nd_vid);
+	  if (!poped) {
+	      ADD_INSN1(ret, nd_line(node), getinstancevariable2,
+			ID2SYM(node->nd_vid));
+	  }
+	  break;
+      }
       case NODE_CONST:{
 	  debugi("nd_vid", node->nd_vid);
 
diff --git a/gc.c b/gc.c
index 6174d2f420..bf8e29def2 100644
--- a/gc.c
+++ b/gc.c
@@ -896,6 +896,7 @@ gc_mark_children(VALUE ptr, int lev)
 	  case NODE_DASGN:
 	  case NODE_DASGN_CURR:
 	  case NODE_IASGN:
+	  case NODE_IASGN2:
 	  case NODE_CVASGN:
 	  case NODE_COLON3:
 	  case NODE_OPT_N:
@@ -935,6 +936,7 @@ gc_mark_children(VALUE ptr, int lev)
 	  case NODE_LVAR:
 	  case NODE_DVAR:
 	  case NODE_IVAR:
+	  case NODE_IVAR2:
 	  case NODE_CVAR:
 	  case NODE_NTH_REF:
 	  case NODE_BACK_REF:
diff --git a/insns.def b/insns.def
index 99401cc395..b84d07f290 100644
--- a/insns.def
+++ b/insns.def
@@ -188,6 +188,22 @@ getinstancevariable
 
 /**
   @c variable
+  @e get class local instance variable id of obj.
+  @j obj のクラスローカルインスタンス変数 id を得る。
+ */
+DEFINE_INSN
+getinstancevariable2
+(ID id)
+()
+(VALUE val)
+{
+    /* need to cache composed id */
+    id = rb_compose_ivar2(id, eval_get_cvar_base(th, GET_ISEQ()));
+    val = rb_ivar_get(GET_SELF(), id);
+}
+
+/**
+  @c variable
   @e set instance variable id of obj as val.
   @j obj のインスタンス変数を val にする。
  */
@@ -202,6 +218,22 @@ setinstancevariable
 
 /**
   @c variable
+  @e set class local instance variable id of obj as val.
+  @j obj のクラスローカルインスタンス変数を val にする。
+ */
+DEFINE_INSN
+setinstancevariable2
+(ID id)
+(VALUE val)
+()
+{
+    /* need to cache composed id */
+    id = rb_compose_ivar2(id, eval_get_cvar_base(th, GET_ISEQ()));
+    rb_ivar_set(GET_SELF(), id, val);
+}
+
+/**
+  @c variable
   @e get class variable id of klass as val.
   @j klass のクラス変数 id を得る。
  */
@@ -901,6 +933,12 @@ defined
 	    expr_type = "instance-variable";
 	}
 	break;
+      case DEFINED_IVAR2:
+	klass = get_cref(GET_ISEQ(), GET_LFP())->nd_clss;
+	if (rb_ivar_defined(GET_SELF(), rb_compose_ivar2(SYM2ID(obj), klass))) {
+	    expr_type = "class local instance-variable";
+	}
+	break;
       case DEFINED_GVAR:
 	if (rb_gvar_defined((struct global_entry *)(obj & ~1))) {
 	    expr_type = "global-variable";
diff --git a/intern.h b/intern.h
index ad8c6b42d6..b3fd3cb0ce 100644
--- a/intern.h
+++ b/intern.h
@@ -398,6 +398,7 @@ ID rb_id_attrset(ID);
 void rb_gc_mark_parser(void);
 int rb_is_const_id(ID);
 int rb_is_instance_id(ID);
+int rb_is_instance2_id(ID);
 int rb_is_class_id(ID);
 int rb_is_local_id(ID);
 int rb_is_junk_id(ID);
@@ -409,6 +410,8 @@ void rb_backref_set(VALUE);
 VALUE rb_lastline_get(void);
 void rb_lastline_set(VALUE);
 VALUE rb_sym_all_symbols(void);
+ID rb_compose_ivar2(ID, VALUE);
+ID rb_decompose_ivar2(ID, VALUE*);
 /* process.c */
 struct rb_exec_arg {
     int argc;
diff --git a/iseq.c b/iseq.c
index 0b53f0b830..9932491d1c 100644
--- a/iseq.c
+++ b/iseq.c
@@ -863,6 +863,8 @@ node_name(int node)
 	return "NODE_GASGN";
     case NODE_IASGN:
 	return "NODE_IASGN";
+    case NODE_IASGN2:
+	return "NODE_IASGN2";
     case NODE_CDECL:
 	return "NODE_CDECL";
     case NODE_CVASGN:
@@ -905,6 +907,8 @@ node_name(int node)
 	return "NODE_GVAR";
     case NODE_IVAR:
 	return "NODE_IVAR";
+    case NODE_IVAR2:
+	return "NODE_IVAR2";
     case NODE_CONST:
 	return "NODE_CONST";
     case NODE_CVAR:
diff --git a/marshal.c b/marshal.c
index 950a1b31d1..1d8b5afa80 100644
--- a/marshal.c
+++ b/marshal.c
@@ -47,7 +47,7 @@ shortlen(long len, BDIGIT *ds)
 #endif
 
 #define MARSHAL_MAJOR   4
-#define MARSHAL_MINOR   8
+#define MARSHAL_MINOR   9
 
 #define TYPE_NIL	'0'
 #define TYPE_TRUE	'T'
@@ -73,6 +73,7 @@ shortlen(long len, BDIGIT *ds)
 #define TYPE_MODULE	'm'
 
 #define TYPE_SYMBOL	':'
+#define TYPE_SYMBOL2	','
 #define TYPE_SYMLINK	';'
 
 #define TYPE_IVAR	'I'
@@ -304,7 +305,7 @@ w_float(double d, struct dump_arg *arg)
 static void
 w_symbol(ID id, struct dump_arg *arg)
 {
-    const char *sym = rb_id2name(id);
+    const char *sym;
     st_data_t num;
 
     if (st_lookup(arg->symbols, id, &num)) {
@@ -312,8 +313,22 @@ w_symbol(ID id, struct dump_arg *arg)
 	w_long((long)num, arg);
     }
     else {
-	w_byte(TYPE_SYMBOL, arg);
-	w_bytes(sym, strlen(sym), arg);
+	if (rb_is_instance2_id(id)) {
+	    VALUE klass;
+	    volatile VALUE path;
+
+	    id = rb_decompose_ivar2(id, &klass);
+	    path = class2path(klass);
+	    w_byte(TYPE_SYMBOL2, arg);
+	    sym = rb_id2name(id);
+	    w_bytes(sym, strlen(sym), arg);
+	    w_bytes(RSTRING_PTR(path), RSTRING_LEN(path), arg);
+	}
+	else {
+	    sym = rb_id2name(id);
+	    w_byte(TYPE_SYMBOL, arg);
+	    w_bytes(sym, strlen(sym), arg);
+	}
 	st_add_direct(arg->symbols, id, arg->symbols->num_entries);
     }
 }
@@ -360,12 +375,14 @@ w_extended(VALUE klass, struct dump_arg *arg, int check)
 static void
 w_class(char type, VALUE obj, struct dump_arg *arg, int check)
 {
+    volatile VALUE p;
     char *path;
 
     VALUE klass = CLASS_OF(obj);
     w_extended(klass, arg, check);
     w_byte(type, arg);
-    path = RSTRING_PTR(class2path(rb_class_real(klass)));
+    p = class2path(rb_class_real(klass));
+    path = RSTRING_PTR(p);
     w_unique(path, arg);
 }
 
@@ -490,7 +507,7 @@ w_object(VALUE obj, struct dump_arg *arg, int limit)
 	    }
 	    w_byte(TYPE_CLASS, arg);
 	    {
-		VALUE path = class2path(obj);
+		volatile VALUE path = class2path(obj);
 		w_bytes(RSTRING_PTR(path), RSTRING_LEN(path), arg);
 	    }
 	    break;
@@ -738,7 +755,9 @@ struct load_arg {
     int taint;
 };
 
+static VALUE r_entry(VALUE v, struct load_arg *arg);
 static VALUE r_object(struct load_arg *arg);
+static VALUE path2class(const char *path);
 
 static int
 r_byte(struct load_arg *arg)
@@ -855,10 +874,24 @@ r_symlink(struct load_arg *arg)
 static ID
 r_symreal(struct load_arg *arg)
 {
-    ID id;
     volatile VALUE s = r_bytes(arg);
+    ID id = rb_intern(RSTRING_PTR(s));
+
+    st_insert(arg->symbols, arg->symbols->num_entries, id);
+
+    return id;
+}
+
+static ID
+r_symivar2(struct load_arg *arg)
+{
+    volatile VALUE s = r_bytes(arg);
+    ID id = rb_intern(RSTRING_PTR(s));
+    VALUE klass;
 
-    id = rb_intern(RSTRING_PTR(s));
+    s = r_bytes(arg);
+    klass = r_entry(path2class(RSTRING_PTR(s)), arg);
+    id = rb_compose_ivar2(id, klass);
     st_insert(arg->symbols, arg->symbols->num_entries, id);
 
     return id;
@@ -867,10 +900,19 @@ r_symreal(struct load_arg *arg)
 static ID
 r_symbol(struct load_arg *arg)
 {
-    if (r_byte(arg) == TYPE_SYMLINK) {
+    int type;
+
+    switch ((type = r_byte(arg))) {
+      case TYPE_SYMBOL:
+	return r_symreal(arg);
+      case TYPE_SYMBOL2:
+	return r_symivar2(arg);
+      case TYPE_SYMLINK:
 	return r_symlink(arg);
+      default:
+	rb_raise(rb_eArgError, "dump format error(0x%x)", type);
+	break;
     }
-    return r_symreal(arg);
 }
 
 static const char*
@@ -1274,6 +1316,10 @@ r_object0(struct load_arg *arg, int *ivp, VALUE extmod)
 	v = ID2SYM(r_symreal(arg));
 	break;
 
+      case TYPE_SYMBOL2:
+	v = ID2SYM(r_symivar2(arg));
+	break;
+
       case TYPE_SYMLINK:
 	v = ID2SYM(r_symlink(arg));
 	break;
diff --git a/node.h b/node.h
index 7deab9646d..453f59f47a 100644
--- a/node.h
+++ b/node.h
@@ -48,6 +48,7 @@ enum node_type {
     NODE_DASGN_CURR,
     NODE_GASGN,
     NODE_IASGN,
+    NODE_IASGN2,
     NODE_CDECL,
     NODE_CVASGN,
     NODE_CVDECL,
@@ -70,6 +71,7 @@ enum node_type {
     NODE_DVAR,
     NODE_GVAR,
     NODE_IVAR,
+    NODE_IVAR2,
     NODE_CONST,
     NODE_CVAR,
     NODE_NTH_REF,
@@ -282,6 +284,7 @@ typedef struct RNode {
 #define NEW_DASGN(v,val) NEW_NODE(NODE_DASGN,v,val,0)
 #define NEW_DASGN_CURR(v,val) NEW_NODE(NODE_DASGN_CURR,v,val,0)
 #define NEW_IASGN(v,val) NEW_NODE(NODE_IASGN,v,val,0)
+#define NEW_IASGN2(v,val) NEW_NODE(NODE_IASGN2,v,val,0)
 #define NEW_CDECL(v,val,path) NEW_NODE(NODE_CDECL,v,val,path)
 #define NEW_CVASGN(v,val) NEW_NODE(NODE_CVASGN,v,val,0)
 #define NEW_CVDECL(v,val) NEW_NODE(NODE_CVDECL,v,val,0)
@@ -294,6 +297,7 @@ typedef struct RNode {
 #define NEW_LVAR(v) NEW_NODE(NODE_LVAR,v,0,local_cnt(v))
 #define NEW_DVAR(v) NEW_NODE(NODE_DVAR,v,0,0)
 #define NEW_IVAR(v) NEW_NODE(NODE_IVAR,v,0,0)
+#define NEW_IVAR2(v) NEW_NODE(NODE_IVAR2,v,0,0)
 #define NEW_CONST(v) NEW_NODE(NODE_CONST,v,0,0)
 #define NEW_CVAR(v) NEW_NODE(NODE_CVAR,v,0,0)
 #define NEW_NTH_REF(n)  NEW_NODE(NODE_NTH_REF,0,n,local_cnt('~'))
diff --git a/parse.y b/parse.y
index 49094f92ef..3f783af352 100644
--- a/parse.y
+++ b/parse.y
@@ -35,19 +35,21 @@
 
 #define ID_SCOPE_SHIFT 3
 #define ID_SCOPE_MASK 0x07
-#define ID_LOCAL    0x01
-#define ID_INSTANCE 0x02
-#define ID_GLOBAL   0x03
-#define ID_ATTRSET  0x04
-#define ID_CONST    0x05
-#define ID_CLASS    0x06
-#define ID_JUNK     0x07
-#define ID_INTERNAL ID_JUNK
+#define ID_LOCAL      0x00
+#define ID_INSTANCE   0x01
+#define ID_INSTANCE2  0x02
+#define ID_GLOBAL     0x03
+#define ID_ATTRSET    0x04
+#define ID_CONST      0x05
+#define ID_CLASS      0x06
+#define ID_JUNK       0x07
+#define ID_INTERNAL   ID_JUNK
 
 #define is_notop_id(id) ((id)>tLAST_TOKEN)
 #define is_local_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_LOCAL)
 #define is_global_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_GLOBAL)
 #define is_instance_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_INSTANCE)
+#define is_instance2_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_INSTANCE2)
 #define is_attrset_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_ATTRSET)
 #define is_const_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_CONST)
 #define is_class_id(id) (is_notop_id(id)&&((id)&ID_SCOPE_MASK)==ID_CLASS)
@@ -7245,6 +7247,9 @@ gettable_gen(struct parser_params *parser, ID id)
     else if (is_instance_id(id)) {
 	return NEW_IVAR(id);
     }
+    else if (is_instance2_id(id)) {
+	return NEW_IVAR2(id);
+    }
     else if (is_const_id(id)) {
 	return NEW_CONST(id);
     }
@@ -7298,6 +7303,9 @@ assignable_gen(struct parser_params *parser, ID id, NODE *val)
     else if (is_instance_id(id)) {
 	return NEW_IASGN(id, val);
     }
+    else if (is_instance2_id(id)) {
+	return NEW_IASGN2(id, val);
+    }
     else if (is_const_id(id)) {
 	if (in_def || in_single)
 	    yyerror("dynamic constant assignment");
@@ -7432,6 +7440,7 @@ node_assign_gen(struct parser_params *parser, NODE *lhs, NODE *rhs)
     switch (nd_type(lhs)) {
       case NODE_GASGN:
       case NODE_IASGN:
+      case NODE_IASGN2:
       case NODE_LASGN:
       case NODE_DASGN:
       case NODE_DASGN_CURR:
@@ -8319,6 +8328,8 @@ static struct symbols {
     ID last_id;
     st_table *sym_id;
     st_table *id_str;
+    st_table *ivar2_id;
+    st_table *id_ivar2;
     VALUE op_sym[tLAST_TOKEN];
 } global_symbols = {tLAST_TOKEN};
 
@@ -8327,11 +8338,38 @@ static struct st_hash_type symhash = {
     rb_str_hash,
 };
 
+struct ivar2_key {
+    ID id;
+    VALUE klass;
+};
+
+static int
+ivar2_cmp(struct ivar2_key *key1, struct ivar2_key *key2)
+{
+    if (key1->id == key2->id && key1->klass == key2->klass) {
+	return 0;
+    }
+    return 1;
+}
+
+static int
+ivar2_hash(struct ivar2_key *key)
+{
+    return (key->id << 8) ^ (key->klass >> 2);
+}
+
+static struct st_hash_type ivar2_hash_type = {
+    ivar2_cmp,
+    ivar2_hash,
+};
+
 void
 Init_sym(void)
 {
     global_symbols.sym_id = st_init_table_with_size(&symhash, 1000);
     global_symbols.id_str = st_init_numtable_with_size(1000);
+    global_symbols.ivar2_id = st_init_table_with_size(&ivar2_hash_type, 1000);
+    global_symbols.id_ivar2 = st_init_numtable_with_size(1000);
 }
 
 void
@@ -8466,6 +8504,9 @@ rb_intern2(const char *name, long len)
 	    m++;
 	    id |= ID_CLASS;
 	}
+	else if (name[1] == '_') {
+	    id |= ID_INSTANCE2;
+	}
 	else {
 	    id |= ID_INSTANCE;
 	}
@@ -8527,6 +8568,39 @@ rb_intern(const char *name)
     return rb_intern2(name, strlen(name));
 }
 
+ID
+rb_compose_ivar2(ID oid, VALUE klass)
+{
+    struct ivar2_key key, *kp;
+    ID id;
+
+    key.id = oid;
+    key.klass = klass;
+    if (st_lookup(global_symbols.ivar2_id, (st_data_t)&key, (st_data_t *)&id))
+	return id;
+
+    kp = ALLOC_N(struct ivar2_key, 1);
+    kp->id = oid; kp->klass = klass;
+    id = ID_INSTANCE2;
+    id |= ++global_symbols.last_id << ID_SCOPE_SHIFT;
+    st_add_direct(global_symbols.ivar2_id, (st_data_t)kp, (st_data_t)id);
+    st_add_direct(global_symbols.id_ivar2, (st_data_t)id, (st_data_t)kp);
+    return id;
+}
+
+ID
+rb_decompose_ivar2(ID id, VALUE *klassp)
+{
+    struct ivar2_key *kp;
+    ID oid;
+
+    if (!st_lookup(global_symbols.id_ivar2, (st_data_t)id, (st_data_t *)&kp)) {
+	return id;
+    }
+    if (klassp) *klassp = kp->klass;
+    return kp->id;
+}
+
 VALUE
 rb_id2str(ID id)
 {
@@ -8636,6 +8710,13 @@ rb_is_instance_id(ID id)
 }
 
 int
+rb_is_instance2_id(ID id)
+{
+    if (is_instance2_id(id)) return Qtrue;
+    return Qfalse;
+}
+
+int
 rb_is_local_id(ID id)
 {
     if (is_local_id(id)) return Qtrue;
diff --git a/string.c b/string.c
index faacf95428..89e88544c9 100644
--- a/string.c
+++ b/string.c
@@ -4690,6 +4690,9 @@ sym_inspect(VALUE sym)
     VALUE str, klass = Qundef;
     ID id = SYM2ID(sym);
 
+    if (rb_is_instance2_id(id)) {
+	id = rb_decompose_ivar2(id, &klass);
+    }
     sym = rb_id2str(id);
     str = rb_str_new(0, RSTRING_LEN(sym)+1);
     RSTRING_PTR(str)[0] = ':';
@@ -4723,6 +4726,9 @@ rb_sym_to_s(VALUE sym)
 {
     ID id = SYM2ID(sym);
 
+    if (rb_is_instance2_id(id)) {
+	id = rb_decompose_ivar2(id, 0);
+    }
     return str_new3(rb_cString, rb_id2str(id));
 }
 
@@ -4868,6 +4874,27 @@ rb_to_id(VALUE name)
     return id;
 }
 
+static VALUE
+sym_div(VALUE sym, VALUE klass)
+{
+    ID id = SYM2ID(sym);
+
+    if (!rb_is_instance2_id(id)) {
+	rb_raise(rb_eArgError, "symbol %s should be local instance variable",
+		 rb_id2name(id));
+    }
+    switch (TYPE(klass)) {
+      case T_CLASS:
+      case T_MODULE:
+	break;
+      default:
+	rb_check_type(klass, T_CLASS);
+	break;
+    }
+    id = rb_compose_ivar2(id, klass);
+    return ID2SYM(id);
+}
+
 /*
  *  A <code>String</code> object holds and manipulates an arbitrary sequence of
  *  bytes, typically representing characters. String objects may be created
@@ -5008,6 +5035,7 @@ Init_String(void)
     rb_define_singleton_method(rb_cSymbol, "all_symbols", rb_sym_all_symbols, 0); /* in parse.y */
     rb_define_singleton_method(rb_cSymbol, "intern", rb_sym_s_intern, 1);
 
+    rb_define_method(rb_cSymbol, "/", sym_div, 1);
     rb_define_method(rb_cSymbol, "==", sym_equal, 1);
     rb_define_method(rb_cSymbol, "to_i", sym_to_i, 0);
     rb_define_method(rb_cSymbol, "inspect", sym_inspect, 0);
diff --git a/vm.c b/vm.c
index 3da1f53486..720aefe79b 100644
--- a/vm.c
+++ b/vm.c
@@ -504,7 +504,7 @@ th_call0(yarv_thread_t *th, VALUE klass, VALUE recv,
 	  val = rb_ivar_set(recv, body->nd_vid, argv[0]);
 	  break;
       }
-      case NODE_IVAR:{
+      case NODE_IVAR: {
 	  if (argc != 0) {
 	      rb_raise(rb_eArgError, "wrong number of arguments (%d for 0)",
 		       argc);
diff --git a/vm_macro.def b/vm_macro.def
index 8a2eb83dbb..e08fb14938 100644
--- a/vm_macro.def
+++ b/vm_macro.def
@@ -293,6 +293,12 @@ MACRO macro_eval_invoke_method(recv, klass, id, num, mn, blockptr)
 	      POP();
 	      break;
 	  }
+	  case NODE_IVAR2:{
+	      ID vid = rb_compose_ivar2(node->nd_vid, mn->nd_clss);
+	      val = rb_ivar_get(recv, vid);
+	      POP();
+	      break;
+	  }
 	  case NODE_BMETHOD:{
 	      VALUE *argv = GET_SP() - num;
 	      val = th_invoke_bmethod(th, id, node->nd_cval,
diff --git a/yarvcore.h b/yarvcore.h
index 8db6b8a7ab..f2c76b2f68 100644
--- a/yarvcore.h
+++ b/yarvcore.h
@@ -585,14 +585,15 @@ typedef VALUE CDHASH;
 
 /* defined? */
 #define DEFINED_IVAR   INT2FIX(1)
-#define DEFINED_GVAR   INT2FIX(2)
-#define DEFINED_CVAR   INT2FIX(3)
-#define DEFINED_CONST  INT2FIX(4)
-#define DEFINED_METHOD INT2FIX(5)
-#define DEFINED_YIELD  INT2FIX(6)
-#define DEFINED_REF    INT2FIX(7)
-#define DEFINED_ZSUPER INT2FIX(8)
-#define DEFINED_FUNC   INT2FIX(9)
+#define DEFINED_IVAR2  INT2FIX(2)
+#define DEFINED_GVAR   INT2FIX(3)
+#define DEFINED_CVAR   INT2FIX(4)
+#define DEFINED_CONST  INT2FIX(5)
+#define DEFINED_METHOD INT2FIX(6)
+#define DEFINED_YIELD  INT2FIX(7)
+#define DEFINED_REF    INT2FIX(8)
+#define DEFINED_ZSUPER INT2FIX(9)
+#define DEFINED_FUNC   INT2FIX(10)
 
 /* VM related object allocate functions */
 /* TODO: should be static functions */