diff --git a/include/ChangeLog b/include/ChangeLog
index 7fd79a010..5fd774f85 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,7 @@
+2011-05-24  Andreas Krebbel  <Andreas.Krebbel@de.ibm.com>
+
+	* opcode/s390.h: Add S390_OPCODE_REG_EVEN flag.
+
 2011-05-17  Alan Modra  <amodra@gmail.com>
 
 	PR ld/12760
diff --git a/include/opcode/s390.h b/include/opcode/s390.h
index 2cbe5f53d..122c60c62 100644
--- a/include/opcode/s390.h
+++ b/include/opcode/s390.h
@@ -147,4 +147,7 @@ extern const struct s390_operand s390_operands[];
    the instruction may be optional.  */
 #define S390_OPERAND_OPTIONAL 0x400
 
+/* The operand needs to be an even register number.  */
+#define S390_OPERAND_REG_EVEN 0x800
+
 	#endif /* S390_H */