This function crashed when regions overalapped. The condition to
optimize the copy of overlapped regions was not correct.
ArmPkg: Add comments to InternalMemCopyMem()
These comments explain the flow of this assembly function.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11486 6f19259b-4bc3-4df7-8a09-765794883524