Apply most suggestions of clang-tidy's performance-unnecessary-value-param

Avoids unnecessary copies. All changes audited & pass tests with asan.
No functional change intended.

llvm-svn: 272190

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp b/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp
index 3eb9ffc17f1..be5c603a38e 100644
--- a/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp
@@ -36,7 +36,7 @@ static const char kDILineInfoBadString[] = "<invalid>";
 static const char kBadString[] = "??";
 
 // Prints source code around in the FileName the Line.
-void DIPrinter::printContext(std::string FileName, int64_t Line) {
+void DIPrinter::printContext(const std::string &FileName, int64_t Line) {
   if (PrintSourceContext <= 0)
     return;