diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
index 22fa271..f681259 100644
--- a/include/llvm/Target/TargetLowering.h
+++ b/include/llvm/Target/TargetLowering.h
@@ -155,8 +155,8 @@
   }
 
   /// getRegClassFor - Return the register class that should be used for the
-  /// specified value type.  This may only be called on legal types.
-  TargetRegisterClass *getRegClassFor(EVT VT) const {
+  /// specified value type.
+  virtual TargetRegisterClass *getRegClassFor(EVT VT) const {
     assert(VT.isSimple() && "getRegClassFor called on illegal type!");
     TargetRegisterClass *RC = RegClassForVT[VT.getSimpleVT().SimpleTy];
     assert(RC && "This value type is not natively supported!");
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 529f711..9db6411 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -266,13 +266,6 @@
     addQRTypeForNEON(MVT::v4i32);
     addQRTypeForNEON(MVT::v2i64);
 
-    // Map v4i64 to QQ registers but do not make the type legal for any
-    // operations. Similarly map v8i64 to QQQQ registers. v4i64 and v8i64 are
-    // only used for REG_SEQUENCE to load / store 4 to 8 consecutive
-    // D registers.
-    addRegisterClass(MVT::v4i64, ARM::QQPRRegisterClass);
-    addRegisterClass(MVT::v8i64, ARM::QQQQPRRegisterClass);
-
     // v2f64 is legal so that QR subregs can be extracted as f64 elements, but
     // neither Neon nor VFP support any arithmetic operations on it.
     setOperationAction(ISD::FADD, MVT::v2f64, Expand);
@@ -586,6 +579,19 @@
   }
 }
 
+/// getRegClassFor - Return the register class that should be used for the
+/// specified value type.
+TargetRegisterClass *ARMTargetLowering::getRegClassFor(EVT VT) const {
+  // Map v4i64 to QQ registers but do not make the type legal. Similarly map
+  // v8i64 to QQQQ registers. v4i64 and v8i64 are only used for REG_SEQUENCE to
+  // load / store 4 to 8 consecutive D registers.
+  if (VT == MVT::v4i64)
+    return ARM::QQPRRegisterClass;
+  else if (VT == MVT::v8i64)
+    return ARM::QQQQPRRegisterClass;
+  return TargetLowering::getRegClassFor(VT);
+}
+
 /// getFunctionAlignment - Return the Log2 alignment of this function.
 unsigned ARMTargetLowering::getFunctionAlignment(const Function *F) const {
   return getTargetMachine().getSubtarget<ARMSubtarget>().isThumb() ? 0 : 1;
diff --git a/lib/Target/ARM/ARMISelLowering.h b/lib/Target/ARM/ARMISelLowering.h
index 7e1132e..54dfb42 100644
--- a/lib/Target/ARM/ARMISelLowering.h
+++ b/lib/Target/ARM/ARMISelLowering.h
@@ -240,6 +240,10 @@
       return Subtarget;
     }
 
+    /// getRegClassFor - Return the register class that should be used for the
+    /// specified value type.
+    virtual TargetRegisterClass *getRegClassFor(EVT VT) const;
+
     /// getFunctionAlignment - Return the Log2 alignment of this function.
     virtual unsigned getFunctionAlignment(const Function *F) const;
 
diff --git a/test/CodeGen/ARM/2010-05-14-IllegalType.ll b/test/CodeGen/ARM/2010-05-14-IllegalType.ll
new file mode 100644
index 0000000..99e5b09
--- /dev/null
+++ b/test/CodeGen/ARM/2010-05-14-IllegalType.ll
@@ -0,0 +1,10 @@
+; RUN: llc -march=thumb -mcpu=cortex-a8 -mtriple=thumbv7-eabi -float-abi=hard < %s | FileCheck %s
+
+target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:32-f32:32:32-f64:32:32-v64:64:64-v128:128:128-a0:0:32-n32"
+target triple = "thumbv7-apple-darwin10"
+
+define <4 x i64> @f_4_i64(<4 x i64> %a, <4 x i64> %b) nounwind {
+; CHECK: vadd.i64
+ %y = add <4 x i64> %a, %b
+ ret <4 x i64> %y
+}