public static Rop opXor(TypeList types) {
    return pickBinaryOp(
        types, XOR_CONST_INT, XOR_CONST_LONG, null, null, XOR_INT, XOR_LONG, null, null);
  }
Returns the appropriate {@code xor} rop for the given types. The result is a shared instance.

@param types {@code non-null;} types of the sources
@return {@code non-null;} an appropriate instance
android/android_framework/dex-maker/src/main/java/com/android/dx/rop/code/Rops.java