+/// Make sure GV is visible from both modules. Delete is true if it is
+/// being deleted from this module.
+/// This also makes sure GV cannot be dropped so that references from
+/// the split module remain valid.
+static void makeVisible(GlobalValue &GV, bool Delete) {
+ bool Local = GV.hasLocalLinkage();
+ if (Local || Delete) {
+ GV.setLinkage(GlobalValue::ExternalLinkage);
+ if (Local)
+ GV.setVisibility(GlobalValue::HiddenVisibility);
+ return;
+ }
+
+ if (!GV.hasLinkOnceLinkage()) {
+ assert(!GV.isDiscardableIfUnused());
+ return;
+ }
+
+ // Map linkonce* to weak* so that llvm doesn't drop this GV.
+ switch(GV.getLinkage()) {
+ default:
+ llvm_unreachable("Unexpected linkage");
+ case GlobalValue::LinkOnceAnyLinkage:
+ GV.setLinkage(GlobalValue::WeakAnyLinkage);
+ return;
+ case GlobalValue::LinkOnceODRLinkage:
+ GV.setLinkage(GlobalValue::WeakODRLinkage);
+ return;
+ }
+}
+