1 files changed, 15 insertions, 3 deletions
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b4ae266f8988..090055dc532d 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1212,12 +1212,22 @@ void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV,
   setDLLImportDLLExport(GV, D);
 }
 
+bool CodeGenModule::shouldMapVisibilityToDLLExport(const NamedDecl *D) const {
+  return D &&
+         (D->getLinkageAndVisibility().getVisibility() == DefaultVisibility) &&
+         ((D->getLinkageAndVisibility().isVisibilityExplicit() &&
+           getLangOpts().isExplicitDefaultVisibilityExportMapping()) ||
+          getLangOpts().isAllDefaultVisibilityExportMapping());
+}
+
 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV,
                                           const NamedDecl *D) const {
   if (D && D->isExternallyVisible()) {
     if (D->hasAttr<DLLImportAttr>())
       GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
-    else if (D->hasAttr<DLLExportAttr>() && !GV->isDeclarationForLinker())
+    else if ((D->hasAttr<DLLExportAttr>() ||
+              shouldMapVisibilityToDLLExport(D)) &&
+             !GV->isDeclarationForLinker())
       GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
   }
 }
@@ -3793,7 +3803,8 @@ llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
     }
 
     // Handle dropped DLL attributes.
-    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>()) {
+    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() &&
+        !shouldMapVisibilityToDLLExport(cast_or_null<NamedDecl>(D))) {
       Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
       setDSOLocal(Entry);
     }
@@ -4105,7 +4116,8 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
     }
 
     // Handle dropped DLL attributes.
-    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
+    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() &&
+        !shouldMapVisibilityToDLLExport(D))
       Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
 
     if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D)