Minor code cleanup in retain/release checker in preparation for some other changes.  Instead of repeatedly checking for GC mode when getting the return effect, just do this computation once.
Minor code cleanup in retain/release checker in preparation for some
other changes.  Instead of repeatedly checking for GC mode when
getting the return effect, just do this computation once.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@71193 91177308-0d34-0410-b5e6-96231b3b80d8

apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang