Further cleanup using dex_instruction_utils.h.

Change-Id: I85aa9e7d744b37ee3d2531c50470cd3fa87dc864
diff --git a/compiler/utils/dex_instruction_utils.h b/compiler/utils/dex_instruction_utils.h
index ad7d750..2c6e525 100644
--- a/compiler/utils/dex_instruction_utils.h
+++ b/compiler/utils/dex_instruction_utils.h
@@ -49,6 +49,10 @@
 
 // NOTE: The following functions disregard quickened instructions.
 
+constexpr bool IsInstructionReturn(Instruction::Code opcode) {
+  return Instruction::RETURN_VOID <= opcode && opcode <= Instruction::RETURN_OBJECT;
+}
+
 constexpr bool IsInstructionInvoke(Instruction::Code opcode) {
   return Instruction::INVOKE_VIRTUAL <= opcode && opcode <= Instruction::INVOKE_INTERFACE_RANGE &&
       opcode != Instruction::RETURN_VOID_BARRIER;