1 files changed, 8 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 43607002544..4903d408ada 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -61,6 +61,11 @@
 using namespace clang;
 using namespace CodeGen;
 
+static llvm::cl::opt<bool> LimitedCoverage(
+    "limited-coverage-experimental", llvm::cl::ZeroOrMore,
+    llvm::cl::desc("Emit limited coverage mapping information (experimental)"),
+    llvm::cl::init(false));
+
 static const char AnnotationSection[] = "llvm.metadata";
 
 static CGCXXABI *createCXXABI(CodeGenModule &CGM) {
@@ -4231,6 +4236,9 @@ void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) {
   case Decl::CXXDestructor: {
     if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody())
       return;
+    SourceManager &SM = getContext().getSourceManager();
+    if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getLocStart()))
+      return;
     auto I = DeferredEmptyCoverageMappingDecls.find(D);
     if (I == DeferredEmptyCoverageMappingDecls.end())
       DeferredEmptyCoverageMappingDecls[D] = true;