Now that hasConstantValue has been made simpler, it may return the
phi node itself if it occurs in an unreachable basic block.  Protect
against this.  Hopefully this will fix some more buildbots.

llvm-svn: 119493
diff --git a/llvm/lib/Analysis/Lint.cpp b/llvm/lib/Analysis/Lint.cpp
index e5e7cd3..0cdb4b1 100644
--- a/llvm/lib/Analysis/Lint.cpp
+++ b/llvm/lib/Analysis/Lint.cpp
@@ -583,7 +583,8 @@
     }
   } else if (PHINode *PN = dyn_cast<PHINode>(V)) {
     if (Value *W = PN->hasConstantValue())
-      return findValueImpl(W, OffsetOk, Visited);
+      if (W != V)
+        return findValueImpl(W, OffsetOk, Visited);
   } else if (CastInst *CI = dyn_cast<CastInst>(V)) {
     if (CI->isNoopCast(TD ? TD->getIntPtrType(V->getContext()) :
                             Type::getInt64Ty(V->getContext())))