C++ Modules TS: add frontend support for building pcm files from module

interface files. At the moment, all declarations (and no macros) are exported,
and 'export' declarations are not supported yet.

llvm-svn: 279794

5 files changed, 57 insertions, 33 deletions

diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index f66ff140aab..3acd64587b1 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -2825,7 +2825,7 @@ const FileEntry *ASTUnit::getPCHFile() {
 }
 
 bool ASTUnit::isModuleFile() {
-  return isMainFileAST() && ASTFileLangOpts.CompilingModule;
+  return isMainFileAST() && ASTFileLangOpts.isCompilingModule();
 }
 
 void ASTUnit::PreambleData::countLines() const {
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 89907f11719..627134e8dd1 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1026,7 +1026,7 @@ static bool compileModuleImpl(CompilerInstance &ImportingInstance,
 
   // Construct a module-generating action. Passing through the module map is
   // safe because the FileManager is shared between the compiler instances.
-  GenerateModuleAction CreateModuleAction(
+  GenerateModuleFromModuleMapAction CreateModuleAction(
       ModMap.getModuleMapFileForUniquing(Module), Module->IsSystem);
 
   ImportingInstance.getDiagnostics().Report(ImportLoc,
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 97c37defa10..3154291d26f 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1116,6 +1116,8 @@ static InputKind ParseFrontendArgs(FrontendOptions &Opts, ArgList &Args,
       Opts.ProgramAction = frontend::FixIt; break;
     case OPT_emit_module:
       Opts.ProgramAction = frontend::GenerateModule; break;
+    case OPT_emit_module_interface:
+      Opts.ProgramAction = frontend::GenerateModuleInterface; break;
     case OPT_emit_pch:
       Opts.ProgramAction = frontend::GeneratePCH; break;
     case OPT_emit_pth:
@@ -2259,6 +2261,7 @@ static void ParsePreprocessorOutputArgs(PreprocessorOutputOptions &Opts,
   case frontend::EmitObj:
   case frontend::FixIt:
   case frontend::GenerateModule:
+  case frontend::GenerateModuleInterface:
   case frontend::GeneratePCH:
   case frontend::GeneratePTH:
   case frontend::ParseSyntaxOnly:
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
index d73d46984cc..eb91940cbbf 100644
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -130,13 +130,13 @@ GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
 std::unique_ptr<ASTConsumer>
 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
                                         StringRef InFile) {
-  std::string Sysroot;
-  std::string OutputFile;
-  std::unique_ptr<raw_pwrite_stream> OS =
-      ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile);
+  std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
   if (!OS)
     return nullptr;
 
+  std::string OutputFile = CI.getFrontendOpts().OutputFile;
+  std::string Sysroot;
+
   auto Buffer = std::make_shared<PCHBuffer>();
   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
 
@@ -151,6 +151,23 @@ GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
 }
 
+bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI, 
+                                                 StringRef Filename) {
+  // Set up embedding for any specified files. Do this before we load any
+  // source files, including the primary module map for the compilation.
+  for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
+    if (const auto *FE = CI.getFileManager().getFile(F, /*openFile*/true))
+      CI.getSourceManager().setFileIsTransient(FE);
+    else
+      CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
+  }
+  if (CI.getFrontendOpts().ModulesEmbedAllFiles)
+    CI.getSourceManager().setAllFilesAreTransient(true);
+
+  return true;
+}
+
+
 static SmallVectorImpl<char> &
 operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
   Includes.append(RHS.begin(), RHS.end());
@@ -266,9 +283,12 @@ collectModuleHeaderIncludes(const LangOptions &LangOpts, FileManager &FileMgr,
   return std::error_code();
 }
 
-bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI, 
-                                                 StringRef Filename) {
-  CI.getLangOpts().CompilingModule = true;
+bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
+    CompilerInstance &CI, StringRef Filename) {
+  CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleMap);
+
+  if (!GenerateModuleAction::BeginSourceFileAction(CI, Filename))
+    return false;
 
   // Find the module map file.
   const FileEntry *ModuleMap =
@@ -279,17 +299,6 @@ bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI,
     return false;
   }
   
-  // Set up embedding for any specified files. Do this before we load any
-  // source files, including the primary module map for the compilation.
-  for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
-    if (const auto *FE = CI.getFileManager().getFile(F, /*openFile*/true))
-      CI.getSourceManager().setFileIsTransient(FE);
-    else
-      CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
-  }
-  if (CI.getFrontendOpts().ModulesEmbedAllFiles)
-    CI.getSourceManager().setAllFilesAreTransient(true);
-
   // Parse the module map file.
   HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
   if (HS.loadModuleMapFile(ModuleMap, IsSystem))
@@ -381,10 +390,8 @@ bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI,
 }
 
 std::unique_ptr<raw_pwrite_stream>
-GenerateModuleAction::ComputeASTConsumerArguments(CompilerInstance &CI,
-                                                  StringRef InFile,
-                                                  std::string &Sysroot,
-                                                  std::string &OutputFile) {
+GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
+                                                    StringRef InFile) {
   // If no output file was provided, figure out where this module would go
   // in the module cache.
   if (CI.getFrontendOpts().OutputFile.empty()) {
@@ -398,16 +405,28 @@ GenerateModuleAction::ComputeASTConsumerArguments(CompilerInstance &CI,
   // We use createOutputFile here because this is exposed via libclang, and we
   // must disable the RemoveFileOnSignal behavior.
   // We use a temporary to avoid race conditions.
-  std::unique_ptr<raw_pwrite_stream> OS =
-      CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
-                          /*RemoveFileOnSignal=*/false, InFile,
-                          /*Extension=*/"", /*useTemporary=*/true,
-                          /*CreateMissingDirectories=*/true);
-  if (!OS)
-    return nullptr;
+  return CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
+                             /*RemoveFileOnSignal=*/false, InFile,
+                             /*Extension=*/"", /*useTemporary=*/true,
+                             /*CreateMissingDirectories=*/true);
+}
 
-  OutputFile = CI.getFrontendOpts().OutputFile;
-  return OS;
+bool GenerateModuleInterfaceAction::BeginSourceFileAction(CompilerInstance &CI,
+                                                          StringRef Filename) {
+  if (!CI.getLangOpts().ModulesTS) {
+    CI.getDiagnostics().Report(diag::err_module_interface_requires_modules_ts);
+    return false;
+  }
+
+  CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
+
+  return GenerateModuleAction::BeginSourceFileAction(CI, Filename);
+}
+
+std::unique_ptr<raw_pwrite_stream>
+GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
+                                                StringRef InFile) {
+  return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
 }
 
 SyntaxOnlyAction::~SyntaxOnlyAction() {
diff --git a/clang/lib/Frontend/FrontendOptions.cpp b/clang/lib/Frontend/FrontendOptions.cpp
index 9ede674e47e..6a82084aff1 100644
--- a/clang/lib/Frontend/FrontendOptions.cpp
+++ b/clang/lib/Frontend/FrontendOptions.cpp
@@ -25,6 +25,8 @@ InputKind FrontendOptions::getInputKindForExtension(StringRef Extension) {
     .Case("mii", IK_PreprocessedObjCXX)
     .Cases("C", "cc", "cp", IK_CXX)
     .Cases("cpp", "CPP", "c++", "cxx", "hpp", IK_CXX)
+    .Case("cppm", IK_CXX)
+    .Case("iim", IK_PreprocessedCXX)
     .Case("cl", IK_OpenCL)
     .Case("cu", IK_CUDA)
     .Cases("ll", "bc", IK_LLVM_IR)