[cxx-interop][nfc] Add a ClangImporter request zone.

This is just the boilerplate for adding a request zone. I haven't actually added any requrests in this commit.

Author: zoecarver

include/swift/Basic/Statistics.def

@@ -268,6 +268,7 @@ FRONTEND_STATISTIC(Sema, NumUnloadedLazyIterableDeclContexts)
 #include "swift/AST/TypeCheckerTypeIDZone.def"
 #include "swift/Sema/IDETypeCheckingRequestIDZone.def"
 #include "swift/IDE/IDERequestIDZone.def"
+#include "swift/ClangImporter/ClangImporterTypeIDZone.def"
 #undef SWIFT_REQUEST
 
 #define SWIFT_REQUEST(ZONE, NAME, Sig, Caching, LocOptions) FRONTEND_STATISTIC(SILGen, NAME)

include/swift/Basic/TypeIDZones.def

@@ -33,5 +33,7 @@
  SWIFT_TYPEID_ZONE(IDETypes, 136)
  SWIFT_TYPEID_ZONE(IDE, 137)
 
+SWIFT_TYPEID_ZONE(ClangImporter, 139)
+
  // N.B. This is not a formal zone and exists solely to support the unit tests.
  SWIFT_TYPEID_ZONE(ArithmeticEvaluator, 255)

include/swift/ClangImporter/ClangImporterRequests.h

@@ -0,0 +1,48 @@
+//===--- ClangImporterRequests.h - Clang Importer Requests ------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines clang-importer requests.
+//
+//===----------------------------------------------------------------------===//
+#ifndef SWIFT_CLANG_IMPORTER_REQUESTS_H
+#define SWIFT_CLANG_IMPORTER_REQUESTS_H
+
+#include "swift/AST/SimpleRequest.h"
+#include "swift/AST/ASTTypeIDs.h"
+#include "swift/AST/EvaluatorDependencies.h"
+
+namespace swift {
+
+#define SWIFT_TYPEID_ZONE ClangImporter
+#define SWIFT_TYPEID_HEADER "swift/ClangImporter/ClangImporterTypeIDZone.def"
+#include "swift/Basic/DefineTypeIDZone.h"
+#undef SWIFT_TYPEID_ZONE
+#undef SWIFT_TYPEID_HEADER
+
+// Set up reporting of evaluated requests.
+template<typename Request>
+void reportEvaluatedRequest(UnifiedStatsReporter &stats,
+                            const Request &request);
+
+#define SWIFT_REQUEST(Zone, RequestType, Sig, Caching, LocOptions)             \
+  template <>                                                                  \
+  inline void reportEvaluatedRequest(UnifiedStatsReporter &stats,              \
+                                     const RequestType &request) {             \
+    ++stats.getFrontendCounters().RequestType;                                 \
+  }
+#include "swift/ClangImporter/ClangImporterTypeIDZone.def"
+#undef SWIFT_REQUEST
+
+} // end namespace swift
+
+#endif // SWIFT_CLANG_IMPORTER_REQUESTS_H
+

include/swift/ClangImporter/ClangImporterTypeIDZone.def

@@ -0,0 +1,17 @@
+//===--- ClangImporterTypeIDZone.def ----------------------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+//
+//  This definition file describes the types in the clang importer
+//  TypeID zone, for use with the TypeID template.
+//
+//===----------------------------------------------------------------------===//
+

include/swift/Subsystems.h

@@ -363,6 +363,12 @@ namespace swift {
   /// Calling registerIDERequestFunctions will invoke this function as well.
   void registerIDETypeCheckRequestFunctions(Evaluator &evaluator);
 
+  /// Register clang importer request functions with the evaluator.
+  ///
+  /// Clients that form an ASTContext and import any Clang APIs should call this function
+  /// after forming the ASTContext.
+  void registerClangImporterRequestFunctions(Evaluator &evaluator);
+
   /// Register SILOptimizer passes necessary for IRGen.
   void registerIRGenSILTransforms(ASTContext &ctx);
 

lib/AST/NameLookupRequests.cpp

@@ -19,6 +19,7 @@
 #include "swift/AST/Evaluator.h"
 #include "swift/AST/Module.h"
 #include "swift/AST/SourceFile.h"
+#include "swift/ClangImporter/ClangImporterRequests.h"
 #include "swift/Subsystems.h"
 
 using namespace swift;

lib/ClangImporter/CMakeLists.txt

@@ -10,6 +10,7 @@ add_swift_host_library(swiftClangImporter STATIC
   ClangAdapter.cpp
   ClangDiagnosticConsumer.cpp
   ClangImporter.cpp
+  ClangImporterRequests.cpp
   ClangModuleDependencyScanner.cpp
   ClangSourceBufferImporter.cpp
   DWARFImporter.cpp

lib/ClangImporter/ClangImporterRequests.cpp

@@ -0,0 +1,37 @@
+//===--- ClangImporterRequests.cpp - Clang Importer Requests --------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#include "swift/AST/NameLookupRequests.h"
+#include "swift/AST/ASTContext.h"
+#include "swift/AST/Decl.h"
+#include "swift/AST/Evaluator.h"
+#include "swift/AST/Module.h"
+#include "swift/AST/SourceFile.h"
+#include "swift/ClangImporter/ClangImporterRequests.h"
+#include "swift/Subsystems.h"
+
+using namespace swift;
+
+// Define request evaluation functions for each of the name lookup requests.
+static AbstractRequestFunction *clangImporterRequestFunctions[] = {
+  nullptr // TODO: remove this whenever a request is actually added.
+#define SWIFT_REQUEST(Zone, Name, Sig, Caching, LocOptions)                    \
+  reinterpret_cast<AbstractRequestFunction *>(&Name::evaluateRequest),
+#include "swift/ClangImporter/ClangImporterTypeIDZone.def"
+#undef SWIFT_REQUEST
+};
+
+void swift::registerClangImporterRequestFunctions(Evaluator &evaluator) {
+  evaluator.registerRequestFunctions(Zone::ClangImporter,
+                                     clangImporterRequestFunctions);
+}
+

lib/Frontend/Frontend.cpp

@@ -221,6 +221,7 @@ bool CompilerInstance::setUpASTContextIfNeeded() {
       SourceMgr, Diagnostics));
   registerParseRequestFunctions(Context->evaluator);
   registerTypeCheckerRequestFunctions(Context->evaluator);
+  registerClangImporterRequestFunctions(Context->evaluator);
   registerSILGenRequestFunctions(Context->evaluator);
   registerSILOptimizerRequestFunctions(Context->evaluator);
   registerTBDGenRequestFunctions(Context->evaluator);

lib/IDE/CompletionInstance.cpp

@@ -338,6 +338,7 @@ bool CompletionInstance::performCachedOperationIfPossible(
   registerParseRequestFunctions(tmpCtx->evaluator);
   registerIDERequestFunctions(tmpCtx->evaluator);
   registerTypeCheckerRequestFunctions(tmpCtx->evaluator);
+  registerClangImporterRequestFunctions(tmpCtx->evaluator);
   registerSILGenRequestFunctions(tmpCtx->evaluator);
   ModuleDecl *tmpM = ModuleDecl::create(Identifier(), *tmpCtx);
   SourceFile *tmpSF = new (*tmpCtx)