[driver] Add -mglobal-merge/-mno-global-merge machine options to enable/disable merging of
globals during codegen.
Fixes <rdar://problem/10017909>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138612 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed