2 files changed, 152 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/CMakeLists.txt b/clang/lib/CodeGen/CMakeLists.txt
index 18f505d8c59..dae14bd3b1c 100644
--- a/clang/lib/CodeGen/CMakeLists.txt
+++ b/clang/lib/CodeGen/CMakeLists.txt
@@ -1,4 +1,5 @@
 set(LLVM_LINK_COMPONENTS
+  ${LLVM_TARGETS_TO_BUILD}
   Analysis
   BitReader
   BitWriter
@@ -63,6 +64,7 @@ add_clang_library(clangCodeGen
   CodeGenAction.cpp
   CodeGenFunction.cpp
   CodeGenModule.cpp
+  CodeGenModuleContainer.cpp
   CodeGenPGO.cpp
   CodeGenTBAA.cpp
   CodeGenTypes.cpp
diff --git a/clang/lib/CodeGen/CodeGenModuleContainer.cpp b/clang/lib/CodeGen/CodeGenModuleContainer.cpp
new file mode 100644
index 00000000000..b1162ccf191
--- /dev/null
+++ b/clang/lib/CodeGen/CodeGenModuleContainer.cpp
@@ -0,0 +1,150 @@
+//===--- CodeGenModuleContainer.cpp - Emit .pcm files ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/CodeGen/CodeGenModuleContainer.h"
+#include "CodeGenModule.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/CodeGen/BackendUtil.h"
+#include "clang/Frontend/CodeGenOptions.h"
+#include "clang/Serialization/ASTWriter.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/TargetRegistry.h"
+#include <memory>
+using namespace clang;
+
+namespace {
+class ModuleContainerGenerator : public CodeGenerator {
+  DiagnosticsEngine &Diags;
+  std::unique_ptr<const llvm::DataLayout> TD;
+  ASTContext *Ctx;
+  const CodeGenOptions CodeGenOpts;
+  const TargetOptions TargetOpts;
+  const LangOptions LangOpts;
+  llvm::LLVMContext VMContext;
+  std::unique_ptr<llvm::Module> M;
+  std::unique_ptr<CodeGen::CodeGenModule> Builder;
+  raw_ostream *OS;
+  SmallVectorImpl<char> *SerializedASTBuffer;
+
+public:
+  ModuleContainerGenerator(DiagnosticsEngine &diags,
+                           const std::string &ModuleName,
+                           const CodeGenOptions &CGO, const TargetOptions &TO,
+                           const LangOptions &LO, raw_ostream *OS,
+                           PCHGenerator *PCHGen)
+      : Diags(diags), CodeGenOpts(CGO), TargetOpts(TO), LangOpts(LO),
+        M(new llvm::Module(ModuleName, VMContext)), OS(OS) {
+    PCHGen->RegisterSerializationFinishedCallback(
+      [&](SmallVectorImpl<char> *Buf){
+        SerializedASTBuffer = Buf;
+      });
+  }
+
+  virtual ~ModuleContainerGenerator() {}
+  llvm::Module *GetModule() override { return M.get(); }
+  llvm::Module *ReleaseModule() override { return M.release(); }
+
+  /// Lifted from ModuleBuilder.
+  const Decl *GetDeclForMangledName(StringRef MangledName) override {
+    GlobalDecl Result;
+    if (!Builder->lookupRepresentativeDecl(MangledName, Result))
+      return nullptr;
+    const Decl *D = Result.getCanonicalDecl().getDecl();
+    if (auto FD = dyn_cast<FunctionDecl>(D)) {
+      if (FD->hasBody(FD))
+        return FD;
+    } else if (auto TD = dyn_cast<TagDecl>(D)) {
+      if (auto Def = TD->getDefinition())
+        return Def;
+    }
+    return D;
+  }
+
+  void Initialize(ASTContext &Context) override {
+    Ctx = &Context;
+    M->setTargetTriple(Ctx->getTargetInfo().getTriple().getTriple());
+    M->setDataLayout(Ctx->getTargetInfo().getTargetDescription());
+    TD.reset(new llvm::DataLayout(Ctx->getTargetInfo().getTargetDescription()));
+    Builder.reset(
+        new CodeGen::CodeGenModule(Context, CodeGenOpts, *M, *TD, Diags));
+  }
+
+  /// Emit a container holding the serialized AST.
+  void HandleTranslationUnit(ASTContext &Ctx) override {
+    if (Diags.hasErrorOccurred()) {
+      if (Builder)
+        Builder->clear();
+      M.reset();
+      return;
+    }
+
+    // Finalize the Builder.
+    if (Builder)
+      Builder->Release();
+
+    // Initialize the backend if we haven't done so already.
+    LLVMInitializeAllTargetInfos();
+    LLVMInitializeAllTargets();
+    LLVMInitializeAllAsmPrinters();
+    LLVMInitializeAllTargetMCs();
+
+    // Ensure the target exists.
+    std::string Error;
+    auto Triple = Ctx.getTargetInfo().getTriple();
+    if (!llvm::TargetRegistry::lookupTarget(Triple.getTriple(), Error))
+      llvm::report_fatal_error(Error);
+
+    // Emit the serialized Clang AST into its own section.
+    auto Size = SerializedASTBuffer->size();
+    auto Int8Ty = llvm::Type::getInt8Ty(VMContext);
+    auto *Ty = llvm::ArrayType::get(Int8Ty, Size);
+    auto *Data = llvm::ConstantDataArray::getString(VMContext,
+        StringRef(SerializedASTBuffer->data(), Size), /*AddNull=*/false);
+    auto *ASTSym = new llvm::GlobalVariable(*M, Ty, /*constant*/ true,
+        llvm::GlobalVariable::InternalLinkage, Data, "__clang_ast");
+    ASTSym->setAlignment(8);
+    if (Triple.isOSBinFormatMachO())
+      // Include Mach-O segment name.
+      ASTSym->setSection("__CLANG,__clangast");
+    else if (Triple.isOSBinFormatCOFF())
+      // Adhere to COFF eight-character limit.
+      ASTSym->setSection("clangast");
+    else
+      ASTSym->setSection("__clangast");
+
+    // Use the LLVM backend to emit the pcm.
+    EmitBackendOutput(Diags, CodeGenOpts, TargetOpts, LangOpts,
+                      Ctx.getTargetInfo().getTargetDescription(), M.get(),
+                      BackendAction::Backend_EmitObj, OS);
+
+    // Make sure the module container hits disk now.
+    OS->flush();
+
+    // Free up some memory, in case the process is kept alive.
+    SerializedASTBuffer->clear();
+  }
+};
+}
+
+CodeGenerator *clang::CreateModuleContainerGenerator(
+    DiagnosticsEngine &Diags, const std::string &ModuleName,
+    const CodeGenOptions &CGO, const TargetOptions &TO, const LangOptions &LO,
+    llvm::raw_ostream *OS, PCHGenerator *PCHGen) {
+  return
+    new ModuleContainerGenerator(Diags, ModuleName, CGO, TO, LO, OS, PCHGen);
+}