Rewrite the addAttr() method.

This now uses the AttributeSet object instead of the Attribute /
AttributeWithIndex objects. It's fairly simple now. It goes through all of the
subsets before the one we're modifying, adds them to the new set. It then adds
the modified subset. And then adds the rest of the subsets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173659 91177308-0d34-0410-b5e6-96231b3b80d8
Rewrite the removeAttr() method.

This now uses the AttributeSet object instead of the Attribute /
AttributeWithIndex objects. It's fairly simple now. It goes through all of the
subsets before the one we're modifying, adds them to the new set. It then adds
the modified subset (with the requested attributes removed). And then adds the
rest of the subsets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173660 91177308-0d34-0410-b5e6-96231b3b80d8
Mid-air collision. reapply r173656.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173661 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor ObjCARCAliasAnalysis into its own file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173662 91177308-0d34-0410-b5e6-96231b3b80d8
Cleaned up includes in various ObjCARC files and removed some whitespace violations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173663 91177308-0d34-0410-b5e6-96231b3b80d8