Allow L symbols in no_dead_strip sections.

If a section cannot be dead stripped, it is safe to use L symbols, since
the linker will keep all of it in the end.

llvm-svn: 221431
diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index c7570ba..6944f71 100644
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -588,6 +588,10 @@
         SMO.getSectionName() == "__cfstring")
       return false;
 
+    // no_dead_strip sections are not atomized in practice.
+    if (SMO.hasAttribute(MachO::S_ATTR_NO_DEAD_STRIP))
+      return false;
+
     switch (SMO.getType()) {
     default:
       return true;