[lld] r188046 - [PECOFF] Fully cover the switch for COMDAT attributes and add a comment.

[Rui Ueyama]

Author: ruiu
Date: Thu Aug  8 20:06:21 2013
New Revision: 188046

URL: http://llvm.org/viewvc/llvm-project?rev=188046&view=rev
Log:
[PECOFF] Fully cover the switch for COMDAT attributes and add a comment.

Modified:
    lld/trunk/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp

Modified: lld/trunk/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp?rev=188046&r1=188045&r2=188046&view=diff
==============================================================================
--- lld/trunk/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp (original)
+++ lld/trunk/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp Thu Aug  8 20:06:21 2013
@@ -85,9 +85,20 @@ DefinedAtom::Merge getMerge(const coff_a
   switch (auxsym->Selection) {
     case llvm::COFF::IMAGE_COMDAT_SELECT_NODUPLICATES:
       return DefinedAtom::mergeNo;
-    default:
-      // FIXME: COFF supports more mergable symbol attributes.
+    case llvm::COFF::IMAGE_COMDAT_SELECT_ANY:
+      return DefinedAtom::mergeAsWeakAndAddressUsed;
+    case llvm::COFF::IMAGE_COMDAT_SELECT_SAME_SIZE:
+    case llvm::COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH:
+    case llvm::COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE:
+    case llvm::COFF::IMAGE_COMDAT_SELECT_LARGEST:
+    case llvm::COFF::IMAGE_COMDAT_SELECT_NEWEST:
+      // FIXME: These attributes has more complicated semantics than the regular
+      // weak symbol. These are mapped to mergeAsWeakAndAddressUsed for now
+      // because the core linker does not support them yet. We eventually have
+      // to implement them for full COFF support.
       return DefinedAtom::mergeAsWeakAndAddressUsed;
+    default:
+      llvm_unreachable("Unknown merge type");
   }
 }