Recommit r224935 with a fix for the ObjC++/AArch64 bug that that revision
introduced.

A test case for the bug was already committed in r225385.

Patch by Rafael Espindola.

llvm-svn: 225534
diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp
index 309e1bf..b3ff001 100644
--- a/llvm/lib/Target/TargetMachine.cpp
+++ b/llvm/lib/Target/TargetMachine.cpp
@@ -21,6 +21,7 @@
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCCodeGenInfo.h"
 #include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCSectionMachO.h"
 #include "llvm/MC/MCTargetOptions.h"
 #include "llvm/MC/SectionKind.h"
 #include "llvm/Support/CommandLine.h"
@@ -169,6 +170,19 @@
   Options.DataSections = V;
 }
 
+static bool canUsePrivateLabel(const MCAsmInfo &AsmInfo,
+                               const MCSection &Section) {
+  if (!AsmInfo.isSectionAtomizableBySymbols(Section))
+    return true;
+
+  // If it is not dead stripped, it is safe to use private labels.
+  const MCSectionMachO &SMO = cast<MCSectionMachO>(Section);
+  if (SMO.hasAttribute(MachO::S_ATTR_NO_DEAD_STRIP))
+    return true;
+
+  return false;
+}
+
 void TargetMachine::getNameWithPrefix(SmallVectorImpl<char> &Name,
                                       const GlobalValue *GV, Mangler &Mang,
                                       bool MayAlwaysUsePrivate) const {
@@ -182,7 +196,7 @@
   const TargetLoweringObjectFile &TLOF =
       getSubtargetImpl()->getTargetLowering()->getObjFileLowering();
   const MCSection *TheSection = TLOF.SectionForGlobal(GV, GVKind, Mang, *this);
-  bool CannotUsePrivateLabel = TLOF.isSectionAtomizableBySymbols(*TheSection);
+  bool CannotUsePrivateLabel = !canUsePrivateLabel(*AsmInfo, *TheSection);
   Mang.getNameWithPrefix(Name, GV, CannotUsePrivateLabel);
 }