Support: tweak comment layout

Make the comment layout more uniform.  NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211854 91177308-0d34-0410-b5e6-96231b3b80d8
Support: update DLLCharacteristics enumeration

Add the new AppContainer characteristic which is import for Windows Store
(Metro) compatible applications.  Add the new Control Flow Guard flag to bring
the enumeration up to date with the current values as of Windows 8.1.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211855 91177308-0d34-0410-b5e6-96231b3b80d8
Use the target lowering we can get off of the DAG rather than off
of the cached target machine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211858 91177308-0d34-0410-b5e6-96231b3b80d8