Avoid including Module.h from ExternalASTSource.h

Module.h takes 86ms to parse, mostly parsing the class itself. Avoid it
if possible. ASTContext.h depends on ExternalASTSource.h.

A few NFC changes were needed to make this possible:

- Move ASTSourceDescriptor to Module.h. This needs Module to be
  complete, and seems more related to modules and AST files than
  external AST sources.
- Move "import complete" bit from Module* pointer int pair to
  NextLocalImport pointer. Required because PointerIntPair<Module*,...>
  requires Module to be complete, and now it may not be.

Reviewed By: aaron.ballman, hans

Differential Revision: https://reviews.llvm.org/D75784

1 files changed, 15 insertions, 0 deletions

diff --git a/clang/lib/Basic/Module.cpp b/clang/lib/Basic/Module.cpp
index 7fb6dee..dd8f111 100644
--- a/clang/lib/Basic/Module.cpp
+++ b/clang/lib/Basic/Module.cpp
@@ -658,3 +658,18 @@ void VisibleModuleSet::setVisible(Module *M, SourceLocation Loc,
   };
   VisitModule({M, nullptr});
 }
+
+ASTSourceDescriptor::ASTSourceDescriptor(const Module &M)
+    : Signature(M.Signature), ClangModule(&M) {
+  if (M.Directory)
+    Path = M.Directory->getName();
+  if (auto *File = M.getASTFile())
+    ASTFile = File->getName();
+}
+
+std::string ASTSourceDescriptor::getModuleName() const {
+  if (ClangModule)
+    return ClangModule->Name;
+  else
+    return std::string(PCHModuleName);
+}