[ms-inline asm] Add a helper function, isMSAsmKeyword().

These require special handling, which we don't currently handle.  This is being
put in place to ensure we don't do invalid symbol table lookups or try to parse
invalid assembly.  The test cases just makes sure the latter isn't happening.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162050 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed