Recommit r256952 "Filtering IR printing for print-after-all/print-before-all"

Fix lit test fail due to outputting an extra line.

Differential Revision: http://reviews.llvm.org/D15776

llvm-svn: 256987
diff --git a/llvm/lib/Analysis/LoopPass.cpp b/llvm/lib/Analysis/LoopPass.cpp
index dc42473..e24a9e4 100644
--- a/llvm/lib/Analysis/LoopPass.cpp
+++ b/llvm/lib/Analysis/LoopPass.cpp
@@ -42,7 +42,11 @@
   }
 
   bool runOnLoop(Loop *L, LPPassManager &) override {
-    P.run(*L);
+    auto BBI = find_if(L->blocks().begin(), L->blocks().end(),
+                       [](BasicBlock *BB) { return BB; });
+    if (BBI != L->blocks().end() &&
+        isFunctionInPrintList((*BBI)->getParent()->getName()))
+      P.run(*L);
     return false;
   }
 };