1 files changed, 18 insertions, 12 deletions

diff --git a/clang/lib/CodeGen/CoverageMappingGen.cpp b/clang/lib/CodeGen/CoverageMappingGen.cpp
index 72ed10d..9c4cab3 100644
--- a/clang/lib/CodeGen/CoverageMappingGen.cpp
+++ b/clang/lib/CodeGen/CoverageMappingGen.cpp
@@ -1606,9 +1606,17 @@ CoverageMappingModuleGen::CoverageMappingModuleGen(
   ProfilePrefixMap = CGM.getCodeGenOpts().ProfilePrefixMap;
 }
 
+std::string CoverageMappingModuleGen::getCurrentDirname() {
+  if (!CGM.getCodeGenOpts().ProfileCompilationDir.empty())
+    return CGM.getCodeGenOpts().ProfileCompilationDir;
+
+  SmallString<256> CWD;
+  llvm::sys::fs::current_path(CWD);
+  return CWD.str().str();
+}
+
 std::string CoverageMappingModuleGen::normalizeFilename(StringRef Filename) {
   llvm::SmallString<256> Path(Filename);
-  llvm::sys::fs::make_absolute(Path);
   llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
   for (const auto &Entry : ProfilePrefixMap) {
     if (llvm::sys::path::replace_path_prefix(Path, Entry.first, Entry.second))
@@ -1689,18 +1697,17 @@ void CoverageMappingModuleGen::addFunctionMappingRecord(
     // also processed by the CoverageMappingWriter which performs
     // additional minimization operations such as reducing the number of
     // expressions.
+    llvm::SmallVector<std::string, 16> FilenameStrs;
     std::vector<StringRef> Filenames;
     std::vector<CounterExpression> Expressions;
     std::vector<CounterMappingRegion> Regions;
-    llvm::SmallVector<std::string, 16> FilenameStrs;
-    llvm::SmallVector<StringRef, 16> FilenameRefs;
-    FilenameStrs.resize(FileEntries.size());
-    FilenameRefs.resize(FileEntries.size());
+    FilenameStrs.resize(FileEntries.size() + 1);
+    FilenameStrs[0] = normalizeFilename(getCurrentDirname());
     for (const auto &Entry : FileEntries) {
       auto I = Entry.second;
       FilenameStrs[I] = normalizeFilename(Entry.first->getName());
-      FilenameRefs[I] = FilenameStrs[I];
     }
+    ArrayRef<std::string> FilenameRefs = llvm::makeArrayRef(FilenameStrs);
     RawCoverageMappingReader Reader(CoverageMapping, FilenameRefs, Filenames,
                                     Expressions, Regions);
     if (Reader.read())
@@ -1717,19 +1724,18 @@ void CoverageMappingModuleGen::emit() {
 
   // Create the filenames and merge them with coverage mappings
   llvm::SmallVector<std::string, 16> FilenameStrs;
-  llvm::SmallVector<StringRef, 16> FilenameRefs;
-  FilenameStrs.resize(FileEntries.size());
-  FilenameRefs.resize(FileEntries.size());
+  FilenameStrs.resize(FileEntries.size() + 1);
+  // The first filename is the current working directory.
+  FilenameStrs[0] = getCurrentDirname();
   for (const auto &Entry : FileEntries) {
     auto I = Entry.second;
     FilenameStrs[I] = normalizeFilename(Entry.first->getName());
-    FilenameRefs[I] = FilenameStrs[I];
   }
 
   std::string Filenames;
   {
     llvm::raw_string_ostream OS(Filenames);
-    CoverageFilenamesSectionWriter(FilenameRefs).write(OS);
+    CoverageFilenamesSectionWriter(FilenameStrs).write(OS);
   }
   auto *FilenamesVal =
       llvm::ConstantDataArray::getString(Ctx, Filenames, false);
@@ -1787,7 +1793,7 @@ unsigned CoverageMappingModuleGen::getFileID(const FileEntry *File) {
   auto It = FileEntries.find(File);
   if (It != FileEntries.end())
     return It->second;
-  unsigned FileID = FileEntries.size();
+  unsigned FileID = FileEntries.size() + 1;
   FileEntries.insert(std::make_pair(File, FileID));
   return FileID;
 }