Add UMULL to ARM integrated assembler.

src/IceAssemblerARM32.h

Index: src/IceAssemblerARM32.h
diff --git a/src/IceAssemblerARM32.h b/src/IceAssemblerARM32.h
index 992b511d88468de9fdbf530b495d45f1274d8606..a7f8c201de1bb81f68a0076b38010dde9e04a017 100644
--- a/src/IceAssemblerARM32.h
+++ b/src/IceAssemblerARM32.h
@@ -210,6 +210,9 @@ public:
   void udiv(const Operand *OpRd, const Operand *OpRn, const Operand *OpSrc1,
             CondARM32::Cond Cond);
 
+  void umull(const Operand *OpRdLo, const Operand *OpRdHi, const Operand *OpRn,
+             const Operand *OpRm, CondARM32::Cond Cond);
+
   static bool classof(const Assembler *Asm) {
     return Asm->getKind() == Asm_ARM32;
   }