[modules] Deserialize CXXCtorInitializer list for a constructor lazily.

Previously we'd deserialize the list of mem-initializers for a constructor when
we deserialized the declaration of the constructor. That could trigger a
significant amount of unnecessary work (pulling in all base classes
recursively, for a start) and was causing problems for the modules buildbot due
to cyclic deserializations. We now deserialize these on demand.

This creates a certain amount of duplication with the handling of
CXXBaseSpecifiers; I'll look into reducing that next.

llvm-svn: 233052

3 files changed, 14 insertions, 0 deletions

diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index 82fb2a6950a..8dc62dd07f2 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -1739,6 +1739,10 @@ CXXConstructorDecl::Create(ASTContext &C, CXXRecordDecl *RD,
                                         isImplicitlyDeclared, isConstexpr);
 }
 
+CXXConstructorDecl::init_const_iterator CXXConstructorDecl::init_begin() const {
+  return CtorInitializers.get(getASTContext().getExternalSource());
+}
+
 CXXConstructorDecl *CXXConstructorDecl::getTargetConstructor() const {
   assert(isDelegatingConstructor() && "Not a delegating constructor!");
   Expr *E = (*init_begin())->getInit()->IgnoreImplicit();
diff --git a/clang/lib/AST/DeclObjC.cpp b/clang/lib/AST/DeclObjC.cpp
index 77995b5261f..a63ba7e698a 100644
--- a/clang/lib/AST/DeclObjC.cpp
+++ b/clang/lib/AST/DeclObjC.cpp
@@ -1820,6 +1820,11 @@ void ObjCImplementationDecl::setIvarInitializers(ASTContext &C,
   }
 }
 
+ObjCImplementationDecl::init_const_iterator
+ObjCImplementationDecl::init_begin() const {
+  return IvarInitializers.get(getASTContext().getExternalSource());
+}
+
 raw_ostream &clang::operator<<(raw_ostream &OS,
                                const ObjCImplementationDecl &ID) {
   OS << ID.getName();
diff --git a/clang/lib/AST/ExternalASTSource.cpp b/clang/lib/AST/ExternalASTSource.cpp
index 88941075dd0..730842a28f6 100644
--- a/clang/lib/AST/ExternalASTSource.cpp
+++ b/clang/lib/AST/ExternalASTSource.cpp
@@ -66,6 +66,11 @@ Stmt *ExternalASTSource::GetExternalDeclStmt(uint64_t Offset) {
   return nullptr;
 }
 
+CXXCtorInitializer **
+ExternalASTSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
+  return nullptr;
+}
+
 CXXBaseSpecifier *
 ExternalASTSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
   return nullptr;