add an explanatory comment about why we drop these in readonly and
not in mergable


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77210 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/TargetAsmInfo.cpp b/lib/Target/TargetAsmInfo.cpp
index ce905ef..f5c1458 100644
--- a/lib/Target/TargetAsmInfo.cpp
+++ b/lib/Target/TargetAsmInfo.cpp
@@ -247,7 +247,9 @@
     case Constant::LocalRelocation:
       // In static relocation model, the linker will resolve all addresses, so
       // the relocation entries will actually be constants by the time the app
-      // starts up.
+      // starts up.  However, we can't put this into a mergable section, because
+      // the linker doesn't take relocations into consideration when it tries to
+      // merge entries in the section.
       if (ReloModel == Reloc::Static)
         return SectionKind::ReadOnly;
               
@@ -258,7 +260,9 @@
     case Constant::GlobalRelocations:
       // In static relocation model, the linker will resolve all addresses, so
       // the relocation entries will actually be constants by the time the app
-      // starts up.
+      // starts up.  However, we can't put this into a mergable section, because
+      // the linker doesn't take relocations into consideration when it tries to
+      // merge entries in the section.
       if (ReloModel == Reloc::Static)
         return SectionKind::ReadOnly;