Revert "[clang][AIX] add option mdefault-visibility-export-mapping"

This caused assertions, see comment on the code review:

llvm/clang/lib/AST/Decl.cpp:1510:
clang::LinkageInfo clang::LinkageComputer::getLVForDecl(const clang::NamedDecl *, clang::LVComputationKind):
Assertion `D->getCachedLinkage() == LV.getLinkage()' failed.

> The option mdefault-visibility-export-mapping is created to allow
> mapping default visibility to an explicit shared library export
> (e.g. dllexport). Exactly how and if this is manifested is target
> dependent (since it depends on how they map dllexport in the IR).
>
> Three values are provided for the option:
>
> * none: the default and behavior without the option, no additional export linkage information is created.
> * explicit: add the export for entities with explict default visibility from the source, including RTTI
> * all: add the export for all entities with default visibility
>
> This option is useful for targets which do not export symbols as part of
> their usual default linkage behaviour (e.g. AIX), such targets
> traditionally specified such information in external files (e.g. export
> lists), but this mapping allows them to use the visibility information
> typically used for this purpose on other (e.g. ELF) platforms.
>
> Reviewed By: MaskRay
>
> Differential Revision: https://reviews.llvm.org/D126340

This reverts commit 8c8a2679a20f621994fa904bcfc68775e7345edc.

1 files changed, 3 insertions, 15 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 090055dc532d..b4ae266f8988 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1212,22 +1212,12 @@ 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>() ||
-              shouldMapVisibilityToDLLExport(D)) &&
-             !GV->isDeclarationForLinker())
+    else if (D->hasAttr<DLLExportAttr>() && !GV->isDeclarationForLinker())
       GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
   }
 }
@@ -3803,8 +3793,7 @@ llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
     }
 
     // Handle dropped DLL attributes.
-    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() &&
-        !shouldMapVisibilityToDLLExport(cast_or_null<NamedDecl>(D))) {
+    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>()) {
       Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
       setDSOLocal(Entry);
     }
@@ -4116,8 +4105,7 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
     }
 
     // Handle dropped DLL attributes.
-    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() &&
-        !shouldMapVisibilityToDLLExport(D))
+    if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
       Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
 
     if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D)