--- a/hotspot/src/cpu/aarch64/vm/macroAssembler_aarch64.hpp	Fri Jun 23 11:41:24 2017 +0800
+++ b/hotspot/src/cpu/aarch64/vm/macroAssembler_aarch64.hpp	Wed Jul 26 15:54:13 2017 +0800
@@ -169,6 +169,7 @@
 
   template<class T>
   inline void cmpw(Register Rd, T imm)  { subsw(zr, Rd, imm); }
+  // imm is limited to 12 bits.
   inline void cmp(Register Rd, unsigned imm)  { subs(zr, Rd, imm); }
 
   inline void cmnw(Register Rd, unsigned imm) { addsw(zr, Rd, imm); }