Add 'const' qualifier to some arrays.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186312 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo: Factor out parsing compile unit DIEs to a separate function. Improve code style and comments.

No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186315 91177308-0d34-0410-b5e6-96231b3b80d8