diff -r 5708a2e568c9 -r 7e85a13bd4a7 src/arch/arm/isa/formats/m5ops.isa
--- a/src/arch/arm/isa/formats/m5ops.isa	Tue May 07 14:47:58 2013 +0200
+++ b/src/arch/arm/isa/formats/m5ops.isa	Tue May 07 14:48:31 2013 +0200
@@ -53,6 +53,7 @@
             case 0x11: return new Deprecated_ivle(machInst);
             case 0x20: return new Deprecated_exit (machInst);
             case 0x21: return new M5exit(machInst);
+            case 0x22: return new M5fail(machInst);
             case 0x31: return new Loadsymbol(machInst);
             case 0x30: return new Initparam(machInst);
             case 0x40: return new Resetstats(machInst);
diff -r 5708a2e568c9 -r 7e85a13bd4a7 src/arch/arm/isa/insts/m5ops.isa
--- a/src/arch/arm/isa/insts/m5ops.isa	Tue May 07 14:47:58 2013 +0200
+++ b/src/arch/arm/isa/insts/m5ops.isa	Tue May 07 14:48:31 2013 +0200
@@ -179,6 +179,17 @@
     decoder_output += BasicConstructor.subst(m5exitIop)
     exec_output += PredOpExecute.subst(m5exitIop)
 
+    m5fail_code = '''
+        PseudoInst::m5fail(xc->tcBase(), join32to64(R1, R0), join32to64(R3, R2));
+    '''
+    m5failIop = InstObjParams("m5fail", "M5fail", "PredOp",
+                                   { "code": m5fail_code,
+                                     "predicate_test": predicateTest },
+                                     ["No_OpClass", "IsNonSpeculative"])
+    header_output += BasicDeclare.subst(m5failIop)
+    decoder_output += BasicConstructor.subst(m5failIop)
+    exec_output += PredOpExecute.subst(m5failIop)
+
     loadsymbolCode = '''
     PseudoInst::loadsymbol(xc->tcBase());
     '''
diff -r 5708a2e568c9 -r 7e85a13bd4a7 util/m5/m5op_arm.S
--- a/util/m5/m5op_arm.S	Tue May 07 14:47:58 2013 +0200
+++ b/util/m5/m5op_arm.S	Tue May 07 14:48:31 2013 +0200
@@ -90,6 +90,7 @@
 SIMPLE_OP(rpns, rpns_func, 0)
 SIMPLE_OP(wakeCPU, wakecpu_func, 0)
 SIMPLE_OP(m5_exit, exit_func, 0)
+SIMPLE_OP(m5_fail, fail_func, 0)
 SIMPLE_OP(m5_initparam, initparam_func, 0)
 SIMPLE_OP(m5_loadsymbol, loadsymbol_func, 0)
 SIMPLE_OP(m5_reset_stats, resetstats_func, 0)