[Clang] implement -fno-eliminate-unused-debug-types

Fixes pr/11710.
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>

Resubmit after breaking Windows and OSX builds.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D80242

1 files changed, 28 insertions, 4 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index f3712ea..67f06ac 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -5392,16 +5392,21 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
           Spec->hasDefinition())
         DI->completeTemplateDefinition(*Spec);
   } LLVM_FALLTHROUGH;
-  case Decl::CXXRecord:
-    if (CGDebugInfo *DI = getModuleDebugInfo())
+  case Decl::CXXRecord: {
+    CXXRecordDecl *CRD = cast<CXXRecordDecl>(D);
+    if (CGDebugInfo *DI = getModuleDebugInfo()) {
+      if (CRD->hasDefinition())
+        DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D)));
       if (auto *ES = D->getASTContext().getExternalSource())
         if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never)
-          DI->completeUnusedClass(cast<CXXRecordDecl>(*D));
+          DI->completeUnusedClass(*CRD);
+    }
     // Emit any static data members, they may be definitions.
-    for (auto *I : cast<CXXRecordDecl>(D)->decls())
+    for (auto *I : CRD->decls())
       if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I))
         EmitTopLevelDecl(I);
     break;
+  }
     // No code generation needed.
   case Decl::UsingShadow:
   case Decl::ClassTemplate:
@@ -5587,6 +5592,25 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
     EmitOMPRequiresDecl(cast<OMPRequiresDecl>(D));
     break;
 
+  case Decl::Typedef:
+  case Decl::TypeAlias: // using foo = bar; [C++11]
+    if (CGDebugInfo *DI = getModuleDebugInfo())
+      DI->EmitAndRetainType(
+          getContext().getTypedefType(cast<TypedefNameDecl>(D)));
+    break;
+
+  case Decl::Record:
+    if (CGDebugInfo *DI = getModuleDebugInfo())
+      if (cast<RecordDecl>(D)->getDefinition())
+        DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D)));
+    break;
+
+  case Decl::Enum:
+    if (CGDebugInfo *DI = getModuleDebugInfo())
+      if (cast<EnumDecl>(D)->getDefinition())
+        DI->EmitAndRetainType(getContext().getEnumType(cast<EnumDecl>(D)));
+    break;
+
   default:
     // Make sure we handled everything we should, every other kind is a
     // non-top-level decl.  FIXME: Would be nice to have an isTopLevelDeclKind