diff --git a/ChangeLog b/ChangeLog
index e50e73d257..9e37cecfd1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Oct 17 05:05:07 2012  Koichi Sasada  <ko1@atdot.net>
+
+	* vm_insnhelper.c (vm_invoke_block): vm_caller_setup_args() can skip
+	  when splat flag is not set.
+
 Wed Oct 17 01:53:47 2012  Koichi Sasada  <ko1@atdot.net>
 
 	* vm_insnhelper.c (vm_getivar, vm_setivar): support index inline cache
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 5e4ad3dc54..072f446f95 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -2032,7 +2032,9 @@ vm_invoke_block(rb_thread_t *th, rb_control_frame_t *reg_cfp, rb_call_info_t *ci
     }
     iseq = block->iseq;
 
-    vm_caller_setup_args(th, GET_CFP(), ci);
+    if (UNLIKELY(ci->flag & VM_CALL_ARGS_SPLAT)) {
+	vm_caller_setup_args(th, GET_CFP(), ci);
+    }
 
     if (BUILTIN_TYPE(iseq) != T_NODE) {
 	int opt_pc;