[unittest] Pass a reference instead of making a copy (NFC)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284065 91177308-0d34-0410-b5e6-96231b3b80d8
Karbin74 · Oct 12, 2016 · 3d62534 · 3d62534
1 parent d05e76c
commit 3d62534
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/unittests/ProfileData/CoverageMappingTest.cpp b/unittests/ProfileData/CoverageMappingTest.cpp
@@ -164,7 +164,7 @@ struct CoverageMappingTest : ::testing::Test {
     return OS.str();
   }
 
-  void readCoverageRegions(std::string Coverage,
+  void readCoverageRegions(const std::string &Coverage,
                            OutputFunctionCoverageData &Data) {
     SmallVector<StringRef, 8> Filenames(Files.size());
     for (const auto &E : Files)