Use a smallstring instead of an std::string in FileChanged to avoid some malloc traffic.
This speeds up -E on xalancbmk by 2.4%
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@40461 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Basic/SourceManager.cpp b/Basic/SourceManager.cpp
index e535470..df13fad 100644
--- a/Basic/SourceManager.cpp
+++ b/Basic/SourceManager.cpp
@@ -231,7 +231,7 @@
/// getSourceName - This method returns the name of the file or buffer that
/// the SourceLocation specifies. This can be modified with #line directives,
/// etc.
-std::string SourceManager::getSourceName(SourceLocation Loc) {
+const char *SourceManager::getSourceName(SourceLocation Loc) {
unsigned FileID = Loc.getFileID();
if (FileID == 0) return "";
return getFileInfo(FileID)->Buffer->getBufferIdentifier();