diff --git a/ChangeLog b/ChangeLog
index b20cc172e2..edeab0d141 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Dec 11 15:36:15 2013  Aman Gupta <ruby@tmm1.net>
+
+	* compile.c (iseq_specialized_instruction): emit opt_aset instruction
+	  to optimize Hash#[]= and Array#[]= when called with Fixnum argument.
+	  [Bug #9227] [ruby-core:58956]
+
 Wed Dec 11 12:38:17 2013  Koichi Sasada  <ko1@atdot.net>
 
 	* eval.c (rb_raise_jump): pop frame after setup exception.
diff --git a/compile.c b/compile.c
index af11bafb9e..25e3652187 100644
--- a/compile.c
+++ b/compile.c
@@ -1955,6 +1955,11 @@ iseq_specialized_instruction(rb_iseq_t *iseq, INSN *iobj)
 		  case idAREF:	 SP_INSN(aref);	  return COMPILE_OK;
 		}
 		break;
+	      case 2:
+		switch (ci->mid) {
+		  case idASET:	 SP_INSN(aset);	  return COMPILE_OK;
+		}
+		break;
 	    }
 	}
 	if (ci->flag & VM_CALL_ARGS_SKIP_SETUP) {