Refactor to avoid code duplication. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217207 91177308-0d34-0410-b5e6-96231b3b80d8
Disable the fix for pr20793 because of a gnu ld bug.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217211 91177308-0d34-0410-b5e6-96231b3b80d8