Tracing to help investigate issues with SjLj spill code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147682 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SjLjEHPrepare.cpp b/lib/CodeGen/SjLjEHPrepare.cpp
index 8e2f74f..a23aaa0 100644
--- a/lib/CodeGen/SjLjEHPrepare.cpp
+++ b/lib/CodeGen/SjLjEHPrepare.cpp
@@ -350,6 +350,8 @@
       for (unsigned i = 0, e = Invokes.size(); i != e; ++i) {
         BasicBlock *UnwindBlock = Invokes[i]->getUnwindDest();
         if (UnwindBlock != BB && LiveBBs.count(UnwindBlock)) {
+          DEBUG(dbgs() << "SJLJ Spill: " << *Inst << " around "
+                << UnwindBlock->getName() << "\n");
           NeedsSpill = true;
           break;
         }