1 files changed, 131 insertions, 0 deletions
diff --git a/clang/lib/Serialization/ASTCommon.h b/clang/lib/Serialization/ASTCommon.h
new file mode 100644
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+++ b/clang/lib/Serialization/ASTCommon.h
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+//===- ASTCommon.h - Common stuff for ASTReader/ASTWriter -*- C++ -*-=========//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines common functions that both ASTReader and ASTWriter use.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_SERIALIZATION_ASTCOMMON_H
+#define LLVM_CLANG_LIB_SERIALIZATION_ASTCOMMON_H
+
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclFriend.h"
+#include "clang/Serialization/ASTBitCodes.h"
+
+namespace clang {
+
+namespace serialization {
+
+enum DeclUpdateKind {
+  UPD_CXX_ADDED_IMPLICIT_MEMBER,
+  UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION,
+  UPD_CXX_ADDED_ANONYMOUS_NAMESPACE,
+  UPD_CXX_ADDED_FUNCTION_DEFINITION,
+  UPD_CXX_ADDED_VAR_DEFINITION,
+  UPD_CXX_POINT_OF_INSTANTIATION,
+  UPD_CXX_INSTANTIATED_CLASS_DEFINITION,
+  UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT,
+  UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER,
+  UPD_CXX_RESOLVED_DTOR_DELETE,
+  UPD_CXX_RESOLVED_EXCEPTION_SPEC,
+  UPD_CXX_DEDUCED_RETURN_TYPE,
+  UPD_DECL_MARKED_USED,
+  UPD_MANGLING_NUMBER,
+  UPD_STATIC_LOCAL_NUMBER,
+  UPD_DECL_MARKED_OPENMP_THREADPRIVATE,
+  UPD_DECL_MARKED_OPENMP_ALLOCATE,
+  UPD_DECL_MARKED_OPENMP_DECLARETARGET,
+  UPD_DECL_EXPORTED,
+  UPD_ADDED_ATTR_TO_RECORD
+};
+
+TypeIdx TypeIdxFromBuiltin(const BuiltinType *BT);
+
+template <typename IdxForTypeTy>
+TypeID MakeTypeID(ASTContext &Context, QualType T, IdxForTypeTy IdxForType) {
+  if (T.isNull())
+    return PREDEF_TYPE_NULL_ID;
+
+  unsigned FastQuals = T.getLocalFastQualifiers();
+  T.removeLocalFastQualifiers();
+
+  if (T.hasLocalNonFastQualifiers())
+    return IdxForType(T).asTypeID(FastQuals);
+
+  assert(!T.hasLocalQualifiers());
+
+  if (const BuiltinType *BT = dyn_cast<BuiltinType>(T.getTypePtr()))
+    return TypeIdxFromBuiltin(BT).asTypeID(FastQuals);
+
+  if (T == Context.AutoDeductTy)
+    return TypeIdx(PREDEF_TYPE_AUTO_DEDUCT).asTypeID(FastQuals);
+  if (T == Context.AutoRRefDeductTy)
+    return TypeIdx(PREDEF_TYPE_AUTO_RREF_DEDUCT).asTypeID(FastQuals);
+
+  return IdxForType(T).asTypeID(FastQuals);
+}
+
+unsigned ComputeHash(Selector Sel);
+
+/// Retrieve the "definitive" declaration that provides all of the
+/// visible entries for the given declaration context, if there is one.
+///
+/// The "definitive" declaration is the only place where we need to look to
+/// find information about the declarations within the given declaration
+/// context. For example, C++ and Objective-C classes, C structs/unions, and
+/// Objective-C protocols, categories, and extensions are all defined in a
+/// single place in the source code, so they have definitive declarations
+/// associated with them. C++ namespaces, on the other hand, can have
+/// multiple definitions.
+const DeclContext *getDefinitiveDeclContext(const DeclContext *DC);
+
+/// Determine whether the given declaration kind is redeclarable.
+bool isRedeclarableDeclKind(unsigned Kind);
+
+/// Determine whether the given declaration needs an anonymous
+/// declaration number.
+bool needsAnonymousDeclarationNumber(const NamedDecl *D);
+
+/// Visit each declaration within \c DC that needs an anonymous
+/// declaration number and call \p Visit with the declaration and its number.
+template<typename Fn> void numberAnonymousDeclsWithin(const DeclContext *DC,
+                                                      Fn Visit) {
+  unsigned Index = 0;
+  for (Decl *LexicalD : DC->decls()) {
+    // For a friend decl, we care about the declaration within it, if any.
+    if (auto *FD = dyn_cast<FriendDecl>(LexicalD))
+      LexicalD = FD->getFriendDecl();
+
+    auto *ND = dyn_cast_or_null<NamedDecl>(LexicalD);
+    if (!ND || !needsAnonymousDeclarationNumber(ND))
+      continue;
+
+    Visit(ND, Index++);
+  }
+}
+
+/// Determine whether the given declaration will be included in the per-module
+/// initializer if it needs to be eagerly handed to the AST consumer. If so, we
+/// should not hand it to the consumer when deserializing it, nor include it in
+/// the list of eagerly deserialized declarations.
+inline bool isPartOfPerModuleInitializer(const Decl *D) {
+  if (isa<ImportDecl>(D))
+    return true;
+  // Template instantiations are notionally in an "instantiation unit" rather
+  // than in any particular translation unit, so they need not be part of any
+  // particular (sub)module's per-module initializer.
+  if (auto *VD = dyn_cast<VarDecl>(D))
+    return !isTemplateInstantiation(VD->getTemplateSpecializationKind());
+  return false;
+}
+
+} // namespace serialization
+
+} // namespace clang
+
+#endif