One request though Aaron: instead of attaching a bunch of files like this, please attach a cvs diff against CVS head. This makes it much easier for us to apply the changes and understand what you changed. To get a diff, use something like this from the top level of your llvm tree:
$ cvs diff -u
If you have other unrelated changes, you can use:
$ cvs diff -u lib/Target/X86/foo.cpp lib/Target/X86/blah.h ...
Okay sorry, I had to get that from the LLVM Mailing list archive as I had a disk crash back then. And never picked the MASMWriter back up again.
Aaron