Support [[clang::ptrauth_vtable_pointer(...)]] attribute

Author: kovdan01

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -2432,6 +2432,47 @@ void CGDebugInfo::CollectVTableInfo(const CXXRecordDecl *RD, llvm::DIFile *Unit,
   if (!VPtrTy)
     VPtrTy = getOrCreateVTablePtrType(Unit);
 
+  if (auto *VptrAuthAttr = RD->getAttr<VTablePointerAuthenticationAttr>()) {
+    unsigned TypedDiscriminator =
+        CGM.getContext().getPointerAuthVTablePointerDiscriminator(RD);
+    auto &LangOpts = CGM.getContext().getLangOpts();
+
+    unsigned Key = VptrAuthAttr->getKey();
+
+    bool HasAddressDiscrimination =
+        LangOpts.PointerAuthVTPtrAddressDiscrimination;
+    if (VptrAuthAttr->getAddressDiscrimination() !=
+        VTablePointerAuthenticationAttr::DefaultAddressDiscrimination) {
+      HasAddressDiscrimination =
+          (VptrAuthAttr->getAddressDiscrimination() ==
+           VTablePointerAuthenticationAttr::AddressDiscrimination);
+    }
+
+    unsigned ExtraDiscriminator = 0;
+
+    switch (VptrAuthAttr->getExtraDiscrimination()) {
+    case VTablePointerAuthenticationAttr::DefaultExtraDiscrimination:
+      if (LangOpts.PointerAuthVTPtrTypeDiscrimination)
+        ExtraDiscriminator = TypedDiscriminator;
+      break;
+    case VTablePointerAuthenticationAttr::TypeDiscrimination:
+      ExtraDiscriminator = TypedDiscriminator;
+      break;
+    case VTablePointerAuthenticationAttr::CustomDiscrimination:
+      ExtraDiscriminator = VptrAuthAttr->getCustomDiscriminationValue();
+      break;
+    case VTablePointerAuthenticationAttr::NoExtraDiscrimination:
+      break;
+    }
+
+    // See CodeGenModule::computeVTPointerAuthentication:
+    // isIsaPointer and authenticatesNullValues are always false.
+    VPtrTy = DBuilder.createPtrAuthQualifiedType(
+        VPtrTy, Key, HasAddressDiscrimination, ExtraDiscriminator,
+        /* isIsaPointer */ false,
+        /* authenticatesNullValues */ false);
+  }
+
   unsigned Size = CGM.getContext().getTypeSize(CGM.getContext().VoidPtrTy);
   llvm::DIType *VPtrMember =
       DBuilder.createMemberType(Unit, getVTableName(RD), Unit, 0, Size, 0, 0,

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp

@@ -1842,6 +1842,48 @@ DWARFASTParserClang::ParseStructureLikeDIE(const SymbolContext &sc,
           attrs.name.GetCString(), tag_decl_kind, attrs.class_language,
           &metadata, attrs.exports_symbols);
     }
+
+    if (metadata.GetIsDynamicCXXType()) {
+      clang::RecordDecl *record_decl = m_ast.GetAsRecordDecl(clang_type);
+      DWARFDIE vptr_type_die =
+          die.GetFirstChild().GetAttributeValueAsReferenceDIE(DW_AT_type);
+      if (vptr_type_die.Tag() == DW_TAG_LLVM_ptrauth_type) {
+        unsigned key = vptr_type_die.GetAttributeValueAsUnsigned(
+            DW_AT_LLVM_ptrauth_key, -1);
+        unsigned discriminator = vptr_type_die.GetAttributeValueAsUnsigned(
+            DW_AT_LLVM_ptrauth_extra_discriminator, -1);
+        unsigned has_addr_discr = vptr_type_die.GetAttributeValueAsUnsigned(
+            DW_AT_LLVM_ptrauth_address_discriminated, -1);
+
+        auto error_missing = [&vptr_type_die](const dw_attr_t attr) {
+          vptr_type_die.GetDWARF()->GetObjectFile()->GetModule()->ReportError(
+              "[{0:x16}]: missing attribute {1:x4} ({2}) required for signed "
+              "vtable pointer",
+              vptr_type_die.GetOffset(), attr, DW_AT_value_to_name(attr));
+        };
+
+        if (key == unsigned(-1))
+          error_missing(DW_AT_LLVM_ptrauth_key);
+        if (discriminator == unsigned(-1))
+          error_missing(DW_AT_LLVM_ptrauth_extra_discriminator);
+        if (has_addr_discr == unsigned(-1))
+          error_missing(DW_AT_LLVM_ptrauth_extra_discriminator);
+
+        record_decl->addAttr(
+            clang::VTablePointerAuthenticationAttr::CreateImplicit(
+                m_ast.getASTContext(),
+                key == 2
+                    ? clang::VTablePointerAuthenticationAttr::ProcessDependent
+                    : clang::VTablePointerAuthenticationAttr::
+                          ProcessIndependent,
+                has_addr_discr ? clang::VTablePointerAuthenticationAttr::
+                                     AddressDiscrimination
+                               : clang::VTablePointerAuthenticationAttr::
+                                     NoAddressDiscrimination,
+                clang::VTablePointerAuthenticationAttr::CustomDiscrimination,
+                discriminator));
+      }
+    }
   }
 
   // Store a forward declaration to this class type in case any