Since these methods will assert if the integer does not fit into 64 bits,
it is necessary to do this check before calling them in
supportedAddressingMode().
Review: Ulrich Weigand.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323866 91177308-0d34-0410-b5e6-96231b3b80d8
