Use -fdebug-compilation-dir to form absolute paths in coverage mappings

This allows users to explicitly request relative paths with
`-fdebug-compilation-dir .`.

Fixes PR43614

Reviewers: vsk, arphaman

Differential Revision: https://reviews.llvm.org/D68733

llvm-svn: 374266

1 files changed, 18 insertions, 7 deletions

diff --git a/clang/lib/CodeGen/CoverageMappingGen.cpp b/clang/lib/CodeGen/CoverageMappingGen.cpp
index 0a7a4fe..a6f6e38 100644
--- a/clang/lib/CodeGen/CoverageMappingGen.cpp
+++ b/clang/lib/CodeGen/CoverageMappingGen.cpp
@@ -1278,13 +1278,6 @@ std::string getCoverageSection(const CodeGenModule &CGM) {
       CGM.getContext().getTargetInfo().getTriple().getObjectFormat());
 }
 
-std::string normalizeFilename(StringRef Filename) {
-  llvm::SmallString<256> Path(Filename);
-  llvm::sys::fs::make_absolute(Path);
-  llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
-  return Path.str().str();
-}
-
 } // end anonymous namespace
 
 static void dump(llvm::raw_ostream &OS, StringRef FunctionName,
@@ -1317,6 +1310,24 @@ static void dump(llvm::raw_ostream &OS, StringRef FunctionName,
   }
 }
 
+CoverageMappingModuleGen::CoverageMappingModuleGen(
+    CodeGenModule &CGM, CoverageSourceInfo &SourceInfo)
+    : CGM(CGM), SourceInfo(SourceInfo), FunctionRecordTy(nullptr) {
+  // Honor -fdebug-compilation-dir in paths in coverage data. Otherwise, use the
+  // regular working directory when normalizing paths.
+  if (!CGM.getCodeGenOpts().DebugCompilationDir.empty())
+    CWD = CGM.getCodeGenOpts().DebugCompilationDir;
+  else
+    llvm::sys::fs::current_path(CWD);
+}
+
+std::string CoverageMappingModuleGen::normalizeFilename(StringRef Filename) {
+  llvm::SmallString<256> Path(Filename);
+  llvm::sys::fs::make_absolute(CWD, Path);
+  llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
+  return Path.str().str();
+}
+
 void CoverageMappingModuleGen::addFunctionMappingRecord(
     llvm::GlobalVariable *NamePtr, StringRef NameValue, uint64_t FuncHash,
     const std::string &CoverageMapping, bool IsUsed) {