diff --git a/compiler/utils/arm/assembler_arm.h b/compiler/utils/arm/assembler_arm.h
index 8730f52..dd0dba2 100644
--- a/compiler/utils/arm/assembler_arm.h
+++ b/compiler/utils/arm/assembler_arm.h
@@ -100,6 +100,10 @@
     return rm_;
   }
 
+  Register GetSecondRegister() const {
+    return rs_;
+  }
+
   enum Type {
     kUnknown = -1,
     kRegister,
diff --git a/compiler/utils/arm/assembler_thumb2.cc b/compiler/utils/arm/assembler_thumb2.cc
index e95db0d..a894319 100644
--- a/compiler/utils/arm/assembler_thumb2.cc
+++ b/compiler/utils/arm/assembler_thumb2.cc
@@ -924,6 +924,8 @@
       use_immediate = true;
       immediate = so.GetImmediate();
     } else {
+      CHECK(!(so.IsRegister() && so.IsShift() && so.GetSecondRegister() != kNoRegister))
+          << "No register-shifted register instruction available in thumb";
       // Adjust rn and rd: only two registers will be emitted.
       switch (opcode) {
         case AND: