Introduce a PCHContainerOperations interface (NFC).
A PCHContainerOperations abstract interface provides operations for
creating and unwrapping containers for serialized ASTs (precompiled
headers and clang modules). The default implementation is
RawPCHContainerOperations, which uses a flat file for the output.
The main application for this interface will be an
ObjectFilePCHContainerOperations implementation that uses LLVM to
wrap the module in an ELF/Mach-O/COFF container to store debug info
alongside the AST.
rdar://problem/20091852
llvm-svn: 240225
diff --git a/clang/lib/Frontend/PCHContainerOperations.cpp b/clang/lib/Frontend/PCHContainerOperations.cpp
new file mode 100644
index 0000000..fd3278b
--- /dev/null
+++ b/clang/lib/Frontend/PCHContainerOperations.cpp
@@ -0,0 +1,70 @@
+//===--- Frontend/PCHContainerOperations.cpp - PCH Containers ---*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines PCHContainerOperations and RawPCHContainerOperation.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/PCHContainerOperations.h"
+#include "clang/AST/ASTConsumer.h"
+#include "llvm/Bitcode/BitstreamReader.h"
+#include "llvm/Support/raw_ostream.h"
+#include "clang/Lex/ModuleLoader.h"
+using namespace clang;
+
+PCHContainerOperations::~PCHContainerOperations() {}
+
+namespace {
+
+/// \brief A PCHContainerGenerator that writes out the PCH to a flat file.
+class PCHContainerGenerator : public ASTConsumer {
+ std::shared_ptr<PCHBuffer> Buffer;
+ raw_pwrite_stream *OS;
+
+public:
+ PCHContainerGenerator(DiagnosticsEngine &Diags,
+ const HeaderSearchOptions &HSO,
+ const PreprocessorOptions &PPO, const TargetOptions &TO,
+ const LangOptions &LO, const std::string &MainFileName,
+ const std::string &OutputFileName,
+ llvm::raw_pwrite_stream *OS,
+ std::shared_ptr<PCHBuffer> Buffer)
+ : Buffer(Buffer), OS(OS) {}
+
+ virtual ~PCHContainerGenerator() {}
+
+ void HandleTranslationUnit(ASTContext &Ctx) override {
+ if (Buffer->IsComplete) {
+ // Make sure it hits disk now.
+ *OS << Buffer->Data;
+ OS->flush();
+ }
+ // Free the space of the temporary buffer.
+ llvm::SmallVector<char, 0> Empty;
+ Buffer->Data = std::move(Empty);
+ }
+};
+}
+
+std::unique_ptr<ASTConsumer>
+RawPCHContainerOperations::CreatePCHContainerGenerator(
+ DiagnosticsEngine &Diags, const HeaderSearchOptions &HSO,
+ const PreprocessorOptions &PPO, const TargetOptions &TO,
+ const LangOptions &LO, const std::string &MainFileName,
+ const std::string &OutputFileName, llvm::raw_pwrite_stream *OS,
+ std::shared_ptr<PCHBuffer> Buffer) const {
+ return llvm::make_unique<PCHContainerGenerator>(
+ Diags, HSO, PPO, TO, LO, MainFileName, OutputFileName, OS, Buffer);
+}
+
+void RawPCHContainerOperations::ExtractPCH(
+ llvm::MemoryBufferRef Buffer, llvm::BitstreamReader &StreamFile) const {
+ StreamFile.init((const unsigned char *)Buffer.getBufferStart(),
+ (const unsigned char *)Buffer.getBufferEnd());
+}