PR27938: Don't remove valid DebugLoc in Scalarizer

Added checks to make sure the Scalarizer::transferMetadata() don't
remove valid debug locations from instructions. This is important as
the verifier pass require that e.g. inlinable callsites have a valid
debug location.

https://llvm.org/bugs/show_bug.cgi?id=27938

Patch by Karl-Johan Karlsson

Reviewers: dblaikie

Differential Revision: http://reviews.llvm.org/D20807

llvm-svn: 272884

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/Scalarizer.cpp b/llvm/lib/Transforms/Scalar/Scalarizer.cpp
index 3f6fd8fa1a7..5e6df0ddf6d 100644
--- a/llvm/lib/Transforms/Scalar/Scalarizer.cpp
+++ b/llvm/lib/Transforms/Scalar/Scalarizer.cpp
@@ -341,7 +341,8 @@ void Scalarizer::transferMetadata(Instruction *Op, const ValueVector &CV) {
            MI != ME; ++MI)
         if (canTransferMetadata(MI->first))
           New->setMetadata(MI->first, MI->second);
-      New->setDebugLoc(Op->getDebugLoc());
+      if (Op->getDebugLoc() && !New->getDebugLoc())
+        New->setDebugLoc(Op->getDebugLoc());
     }
   }
 }