Index: lib/Target/ARM/ARMInstrThumb2.td
===================================================================
--- lib/Target/ARM/ARMInstrThumb2.td
+++ lib/Target/ARM/ARMInstrThumb2.td
@@ -3632,7 +3632,7 @@
 // Branch and Exchange Jazelle -- for disassembly only
 // Rm = Inst{19-16}
 def t2BXJ : T2I<(outs), (ins rGPR:$func), NoItinerary, "bxj", "\t$func", []>,
-    Sched<[WriteBr]> {
+    Sched<[WriteBr]>, Requires<[IsThumb2, IsNotMClass, PreV8]> {
   bits<4> func;
   let Inst{31-27} = 0b11110;
   let Inst{26} = 0;
Index: test/MC/ARM/thumb2-bxj.s
===================================================================
--- /dev/null
+++ test/MC/ARM/thumb2-bxj.s
@@ -0,0 +1,10 @@
+@ RUN: llvm-mc -triple=thumbv6t2--none-eabi -show-encoding < %s | FileCheck %s
+@ RUN: llvm-mc -triple=thumbv7a--none-eabi -show-encoding < %s | FileCheck %s
+@ RUN: llvm-mc -triple=thumbv7r--none-eabi -show-encoding < %s | FileCheck %s
+@ RUN: not llvm-mc -triple=thumbv7m--none-eabi -show-encoding < %s 2>&1 | FileCheck %s --check-prefix=UNDEF
+@ RUN: not llvm-mc -triple=thumbv8a--none-eabi -show-encoding < %s 2>&1 | FileCheck %s --check-prefix=UNDEF
+
+        bxj r2
+
+@ CHECK: bxj r2                      @ encoding: [0xc2,0xf3,0x00,0x8f]
+@ UNDEF: error: instruction requires: arm-mode