Unbreak ppc debug support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46665 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 79fc16b..e17f82d 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -1076,6 +1076,9 @@
   GlobalAddressSDNode *GSDN = cast<GlobalAddressSDNode>(Op);
   GlobalValue *GV = GSDN->getGlobal();
   SDOperand GA = DAG.getTargetGlobalAddress(GV, PtrVT, GSDN->getOffset());
+  // If it's a debug information descriptor, don't mess with it.
+  if (DAG.isVerifiedDebugInfoDesc(Op))
+    return GA;
   SDOperand Zero = DAG.getConstant(0, PtrVT);
   
   const TargetMachine &TM = DAG.getTarget();