2 files changed, 21 insertions, 15 deletions
diff --git a/ChangeLog b/ChangeLog
index 34fb7d26b0..ecddcdc68c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sat Dec 14 00:22:16 2013  Nobuyoshi Nakada  <[email protected]>
+
+	* thread.c: (exec_recursive): use rb_catch_protect() instead of
+	  rb_catch_obj() and PUSH_TAG(), and reduce pushing tags and
+	  machine stack usage.
+
 Sat Dec 14 00:18:08 2013  Nobuyoshi Nakada  <[email protected]>
 
 	* proc.c (mnew_from_me): achieve the original defined_class from
diff --git a/thread.c b/thread.c
index 2ee530f6b6..0e743c68e0 100644
--- a/thread.c
+++ b/thread.c
@@ -4880,19 +4880,7 @@ static VALUE
 exec_recursive_i(RB_BLOCK_CALL_FUNC_ARGLIST(tag, data))
 {
     struct exec_recursive_params *p = (void *)data;
-    VALUE result = Qundef;
-    int state;
-
-    recursive_push(p->list, p->objid, p->pairid);
-    PUSH_TAG();
-    if ((state = EXEC_TAG()) == 0) {
-	result = (*p->func)(p->obj, p->arg, FALSE);
-    }
-    POP_TAG();
-    recursive_pop(p->list, p->objid, p->pairid);
-    if (state)
-	JUMP_TAG(state);
-    return result;
+    return (*p->func)(p->obj, p->arg, FALSE);
 }
 
 /*
@@ -4926,18 +4914,30 @@ exec_recursive(VALUE (*func) (VALUE, VALUE, int), VALUE obj, VALUE pairid, VALUE
 	return (*func)(obj, arg, TRUE);
     }
     else {
+	int state;
+
 	p.func = func;
 
 	if (outermost) {
 	    recursive_push(p.list, ID2SYM(recursive_key), 0);
-	    result = rb_catch_obj(p.list, exec_recursive_i, (VALUE)&p);
+	    recursive_push(p.list, p.objid, p.pairid);
+	    result = rb_catch_protect(p.list, exec_recursive_i, (VALUE)&p, &state);
+	    recursive_pop(p.list, p.objid, p.pairid);
 	    recursive_pop(p.list, ID2SYM(recursive_key), 0);
+	    if (state) JUMP_TAG(state);
 	    if (result == p.list) {
 		result = (*func)(obj, arg, TRUE);
 	    }
 	}
 	else {
-	    result = exec_recursive_i(0, (VALUE)&p, 0, 0, Qnil);
+	    recursive_push(p.list, p.objid, p.pairid);
+	    PUSH_TAG();
+	    if ((state = EXEC_TAG()) == 0) {
+		result = (*func)(obj, arg, FALSE);
+	    }
+	    POP_TAG();
+	    recursive_pop(p.list, p.objid, p.pairid);
+	    if (state) JUMP_TAG(state);
 	}
     }
     *(volatile struct exec_recursive_params *)&p;