Clarify some important bits


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48010 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp
index eed36c1..5545af6 100644
--- a/lib/Linker/LinkModules.cpp
+++ b/lib/Linker/LinkModules.cpp
@@ -516,8 +516,9 @@
                            SGV->isConstant(), SGV->getLinkage(), /*init*/0,
                            "", Dest);
 
-      // Propagate alignment, section and visibility info.
+      // Set alignment allowing CopyGVAttributes merge it with alignment of SGV.
       NewDGV->setAlignment(DGV->getAlignment());
+      // Propagate alignment, section and visibility info.
       CopyGVAttributes(NewDGV, SGV);
 
       // Make sure to remember this mapping...