A doccomment for CombineTo, and some NFC refactorings
A doccomment for CombineTo, and some NFC refactorings

Summary:
Caching SDLoc(N), instead of recreating it in every single
function call, keeps the code denser, and allows to unwrap long lines.

Reviewers: sunfish, atrick, sdmitrouk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13726

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@250305 91177308-0d34-0410-b5e6-96231b3b80d8

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