Remove executable permissions on a text file
Ensure bitcode encoding of linkage types stays stable. Patch by Boaz Ouriel
Revamp error checking in the ms inline asm parser.

- Actually abort when an error occurred.
- Check that the frontend lookup worked when parsing length/size/type operators.

Tested by a clang test. PR18096.
Reenable ms inline asm test.

LLVM r196044 should make it pass.