tools/clang-import-test/clang-import-test.cpp - third_party/swift-clang - Git at Google

 //===-- import-test.cpp - ASTImporter/ExternalASTSource testbed -----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//

 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTImporter.h"
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/IdentifierTable.h"
 #include "clang/Basic/SourceLocation.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Basic/TargetOptions.h"
 #include "clang/CodeGen/ModuleBuilder.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Frontend/TextDiagnosticBuffer.h"
 #include "clang/Lex/Lexer.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Parse/ParseAST.h"

 #include "llvm/IR/LLVMContext.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/Signals.h"

 #include <memory>
 #include <string>

 using namespace clang;

 static llvm::cl::opt<std::string> Expression(
     "expression", llvm::cl::Required,
     llvm::cl::desc("Path to a file containing the expression to parse"));

 static llvm::cl::list<std::string>
     Imports("import", llvm::cl::ZeroOrMore,
             llvm::cl::desc("Path to a file containing declarations to import"));

 static llvm::cl::list<std::string>
     ClangArgs("Xcc", llvm::cl::ZeroOrMore,
               llvm::cl::desc("Argument to pass to the CompilerInvocation"),
               llvm::cl::CommaSeparated);

 namespace init_convenience {
 class TestDiagnosticConsumer : public DiagnosticConsumer {
 private:
   std::unique_ptr<TextDiagnosticBuffer> Passthrough;
   const LangOptions *LangOpts = nullptr;

 public:
   TestDiagnosticConsumer()
       : Passthrough(llvm::make_unique<TextDiagnosticBuffer>()) {}

   virtual void BeginSourceFile(const LangOptions &LangOpts,
                                const Preprocessor *PP = nullptr) override {
     this->LangOpts = &LangOpts;
     return Passthrough->BeginSourceFile(LangOpts, PP);
   }

   virtual void EndSourceFile() override {
     this->LangOpts = nullptr;
     Passthrough->EndSourceFile();
   }

   virtual bool IncludeInDiagnosticCounts() const override {
     return Passthrough->IncludeInDiagnosticCounts();
   }

 private:
   static void PrintSourceForLocation(const SourceLocation &Loc,
                                      SourceManager &SM) {
     const char *LocData = SM.getCharacterData(Loc, /*Invalid=*/nullptr);
     unsigned LocColumn =
         SM.getSpellingColumnNumber(Loc, /*Invalid=*/nullptr) - 1;
     FileID FID = SM.getFileID(Loc);
     llvm::MemoryBuffer *Buffer = SM.getBuffer(FID, Loc, /*Invalid=*/nullptr);

     assert(LocData >= Buffer->getBufferStart() &&
            LocData < Buffer->getBufferEnd());

     const char *LineBegin = LocData - LocColumn;

     assert(LineBegin >= Buffer->getBufferStart());

     const char *LineEnd = nullptr;

     for (LineEnd = LineBegin; *LineEnd != '\n' && *LineEnd != '\r' &&
                               LineEnd < Buffer->getBufferEnd();
          ++LineEnd)
       ;

     llvm::StringRef LineString(LineBegin, LineEnd - LineBegin);

     llvm::errs() << LineString << '\n';
     llvm::errs().indent(LocColumn);
     llvm::errs() << '^';
   }

   virtual void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
                                 const Diagnostic &Info) override {
     if (Info.hasSourceManager() && LangOpts) {
       SourceManager &SM = Info.getSourceManager();

       if (Info.getLocation().isValid()) {
         Info.getLocation().print(llvm::errs(), SM);
         llvm::errs() << ": ";
       }

       SmallString<16> DiagText;
       Info.FormatDiagnostic(DiagText);
       llvm::errs() << DiagText << '\n';

       if (Info.getLocation().isValid()) {
         PrintSourceForLocation(Info.getLocation(), SM);
       }

       for (const CharSourceRange &Range : Info.getRanges()) {
         bool Invalid = true;
         StringRef Ref = Lexer::getSourceText(Range, SM, *LangOpts, &Invalid);
         if (!Invalid) {
           llvm::errs() << Ref << '\n';
         }
       }
     }
     DiagnosticConsumer::HandleDiagnostic(DiagLevel, Info);
   }
 };

 std::unique_ptr<CompilerInstance>
 BuildCompilerInstance(ArrayRef<const char *> ClangArgv) {
   auto Ins = llvm::make_unique<CompilerInstance>();
   auto DC = llvm::make_unique<TestDiagnosticConsumer>();
   const bool ShouldOwnClient = true;
   Ins->createDiagnostics(DC.release(), ShouldOwnClient);

   auto Inv = llvm::make_unique<CompilerInvocation>();

   CompilerInvocation::CreateFromArgs(*Inv, ClangArgv.data(),
                                      &ClangArgv.data()[ClangArgv.size()],
                                      Ins->getDiagnostics());

   Inv->getLangOpts()->CPlusPlus = true;
   Inv->getLangOpts()->CPlusPlus11 = true;
   Inv->getHeaderSearchOpts().UseLibcxx = true;
   Inv->getLangOpts()->Bool = true;
   Inv->getLangOpts()->WChar = true;
   Inv->getLangOpts()->Blocks = true;
   Inv->getLangOpts()->DebuggerSupport = true;
   Inv->getLangOpts()->SpellChecking = false;
   Inv->getLangOpts()->ThreadsafeStatics = false;
   Inv->getLangOpts()->AccessControl = false;
   Inv->getLangOpts()->DollarIdents = true;
   Inv->getCodeGenOpts().setDebugInfo(codegenoptions::FullDebugInfo);
   Inv->getTargetOpts().Triple = llvm::sys::getDefaultTargetTriple();

   Ins->setInvocation(std::move(Inv));

   TargetInfo *TI = TargetInfo::CreateTargetInfo(
       Ins->getDiagnostics(), Ins->getInvocation().TargetOpts);
   Ins->setTarget(TI);
   Ins->getTarget().adjust(Ins->getLangOpts());
   Ins->createFileManager();
   Ins->createSourceManager(Ins->getFileManager());
   Ins->createPreprocessor(TU_Complete);

   return Ins;
 }

 std::unique_ptr<ASTContext>
 BuildASTContext(CompilerInstance &CI, SelectorTable &ST, Builtin::Context &BC) {
   auto AST = llvm::make_unique<ASTContext>(
       CI.getLangOpts(), CI.getSourceManager(),
       CI.getPreprocessor().getIdentifierTable(), ST, BC);
   AST->InitBuiltinTypes(CI.getTarget());
   return AST;
 }

 std::unique_ptr<CodeGenerator> BuildCodeGen(CompilerInstance &CI,
                                             llvm::LLVMContext &LLVMCtx) {
   StringRef ModuleName("$__module");
   return std::unique_ptr<CodeGenerator>(CreateLLVMCodeGen(
       CI.getDiagnostics(), ModuleName, CI.getHeaderSearchOpts(),
       CI.getPreprocessorOpts(), CI.getCodeGenOpts(), LLVMCtx));
 }
 } // end namespace

 namespace {
 class TestExternalASTSource : public ExternalASTSource {
 private:
   llvm::ArrayRef<std::unique_ptr<CompilerInstance>> ImportCIs;
   std::map<CompilerInstance *, std::unique_ptr<ASTImporter>> ForwardImporters;
   std::map<CompilerInstance *, std::unique_ptr<ASTImporter>> ReverseImporters;

 public:
   TestExternalASTSource(
       CompilerInstance &ExpressionCI,
       llvm::ArrayRef<std::unique_ptr<CompilerInstance>> ImportCIs)
       : ImportCIs(ImportCIs) {
     for (const std::unique_ptr<CompilerInstance> &ImportCI : ImportCIs) {
       ForwardImporters[ImportCI.get()] = llvm::make_unique<ASTImporter>(
           ExpressionCI.getASTContext(), ExpressionCI.getFileManager(),
           ImportCI->getASTContext(), ImportCI->getFileManager(),
           /*MinimalImport=*/true);
       ReverseImporters[ImportCI.get()] = llvm::make_unique<ASTImporter>(
           ImportCI->getASTContext(), ImportCI->getFileManager(),
           ExpressionCI.getASTContext(), ExpressionCI.getFileManager(),
           /*MinimalImport=*/true);
     }
   }

   bool FindExternalVisibleDeclsByName(const DeclContext *DC,
                                       DeclarationName Name) override {
     llvm::SmallVector<NamedDecl *, 1> Decls;

     if (isa<TranslationUnitDecl>(DC)) {
       for (const std::unique_ptr<CompilerInstance> &I : ImportCIs) {
         DeclarationName FromName = ReverseImporters[I.get()]->Import(Name);
         DeclContextLookupResult Result =
             I->getASTContext().getTranslationUnitDecl()->lookup(FromName);
         for (NamedDecl *FromD : Result) {
           NamedDecl *D =
               llvm::cast<NamedDecl>(ForwardImporters[I.get()]->Import(FromD));
           Decls.push_back(D);
         }
       }
     }
     if (Decls.empty()) {
       return false;
     } else {
       SetExternalVisibleDeclsForName(DC, Name, Decls);
       return true;
     }
   }
 };

 void AddExternalSource(
     CompilerInstance &CI,
     llvm::ArrayRef<std::unique_ptr<CompilerInstance>> Imports) {
   ASTContext &AST = CI.getASTContext();
   auto ES = llvm::make_unique<TestExternalASTSource>(CI, Imports);
   AST.setExternalSource(ES.release());
   AST.getTranslationUnitDecl()->setHasExternalVisibleStorage();
 }

 llvm::Error ParseSource(const std::string &Path, CompilerInstance &CI,
                         CodeGenerator &CG) {
   SourceManager &SM = CI.getSourceManager();
   const FileEntry *FE = CI.getFileManager().getFile(Path);
   if (!FE) {
     return llvm::make_error<llvm::StringError>(
         llvm::Twine("Couldn't open ", Path), std::error_code());
   }
   SM.setMainFileID(SM.createFileID(FE, SourceLocation(), SrcMgr::C_User));
   ParseAST(CI.getPreprocessor(), &CG, CI.getASTContext());
   return llvm::Error::success();
 }

 llvm::Expected<std::unique_ptr<CompilerInstance>>
 Parse(const std::string &Path,
       llvm::ArrayRef<std::unique_ptr<CompilerInstance>> Imports) {
   std::vector<const char *> ClangArgv(ClangArgs.size());
   std::transform(ClangArgs.begin(), ClangArgs.end(), ClangArgv.begin(),
                  [](const std::string &s) -> const char * { return s.data(); });
   std::unique_ptr<CompilerInstance> CI =
       init_convenience::BuildCompilerInstance(ClangArgv);
   auto ST = llvm::make_unique<SelectorTable>();
   auto BC = llvm::make_unique<Builtin::Context>();
   std::unique_ptr<ASTContext> AST =
       init_convenience::BuildASTContext(*CI, *ST, *BC);
   CI->setASTContext(AST.release());
   AddExternalSource(*CI, Imports);

   auto LLVMCtx = llvm::make_unique<llvm::LLVMContext>();
   std::unique_ptr<CodeGenerator> CG =
       init_convenience::BuildCodeGen(*CI, *LLVMCtx);
   CG->Initialize(CI->getASTContext());

   CI->getDiagnosticClient().BeginSourceFile(CI->getLangOpts(),
                                             &CI->getPreprocessor());
   if (llvm::Error PE = ParseSource(Path, *CI, *CG)) {
     return std::move(PE);
   }
   CI->getDiagnosticClient().EndSourceFile();
   if (CI->getDiagnosticClient().getNumErrors()) {
     return llvm::make_error<llvm::StringError>(
         "Errors occured while parsing the expression.", std::error_code());
   } else {
     return std::move(CI);
   }
 }
 } // end namespace

 int main(int argc, const char **argv) {
   const bool DisableCrashReporting = true;
   llvm::sys::PrintStackTraceOnErrorSignal(argv[0], DisableCrashReporting);
   llvm::cl::ParseCommandLineOptions(argc, argv);
   std::vector<std::unique_ptr<CompilerInstance>> ImportCIs;
   for (auto I : Imports) {
     llvm::Expected<std::unique_ptr<CompilerInstance>> ImportCI = Parse(I, {});
     if (auto E = ImportCI.takeError()) {
       llvm::errs() << llvm::toString(std::move(E));
       exit(-1);
     } else {
       ImportCIs.push_back(std::move(*ImportCI));
     }
   }
   llvm::Expected<std::unique_ptr<CompilerInstance>> ExpressionCI =
       Parse(Expression, ImportCIs);
   if (auto E = ExpressionCI.takeError()) {
     llvm::errs() << llvm::toString(std::move(E));
     exit(-1);
   } else {
     return 0;
   }
 }
	//===-- import-test.cpp - ASTImporter/ExternalASTSource testbed -----------===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//

	#include "clang/AST/ASTContext.h"
	#include "clang/AST/ASTImporter.h"
	#include "clang/Basic/Builtins.h"
	#include "clang/Basic/IdentifierTable.h"
	#include "clang/Basic/SourceLocation.h"
	#include "clang/Basic/TargetInfo.h"
	#include "clang/Basic/TargetOptions.h"
	#include "clang/CodeGen/ModuleBuilder.h"
	#include "clang/Frontend/CompilerInstance.h"
	#include "clang/Frontend/TextDiagnosticBuffer.h"
	#include "clang/Lex/Lexer.h"
	#include "clang/Lex/Preprocessor.h"
	#include "clang/Parse/ParseAST.h"

	#include "llvm/IR/LLVMContext.h"
	#include "llvm/Support/CommandLine.h"
	#include "llvm/Support/Error.h"
	#include "llvm/Support/Host.h"
	#include "llvm/Support/Signals.h"

	#include <memory>
	#include <string>

	using namespace clang;

	static llvm::cl::opt<std::string> Expression(
	"expression", llvm::cl::Required,
	llvm::cl::desc("Path to a file containing the expression to parse"));

	static llvm::cl::list<std::string>
	Imports("import", llvm::cl::ZeroOrMore,
	llvm::cl::desc("Path to a file containing declarations to import"));

	static llvm::cl::list<std::string>
	ClangArgs("Xcc", llvm::cl::ZeroOrMore,
	llvm::cl::desc("Argument to pass to the CompilerInvocation"),
	llvm::cl::CommaSeparated);

	namespace init_convenience {
	class TestDiagnosticConsumer : public DiagnosticConsumer {
	private:
	std::unique_ptr<TextDiagnosticBuffer> Passthrough;
	const LangOptions *LangOpts = nullptr;

	public:
	TestDiagnosticConsumer()
	: Passthrough(llvm::make_unique<TextDiagnosticBuffer>()) {}

	virtual void BeginSourceFile(const LangOptions &LangOpts,
	const Preprocessor *PP = nullptr) override {
	this->LangOpts = &LangOpts;
	return Passthrough->BeginSourceFile(LangOpts, PP);
	}

	virtual void EndSourceFile() override {
	this->LangOpts = nullptr;
	Passthrough->EndSourceFile();
	}

	virtual bool IncludeInDiagnosticCounts() const override {
	return Passthrough->IncludeInDiagnosticCounts();
	}

	private:
	static void PrintSourceForLocation(const SourceLocation &Loc,
	SourceManager &SM) {
	const char LocData = SM.getCharacterData(Loc, /Invalid=*/nullptr);
	unsigned LocColumn =
	SM.getSpellingColumnNumber(Loc, /Invalid=/nullptr) - 1;
	FileID FID = SM.getFileID(Loc);
	llvm::MemoryBuffer Buffer = SM.getBuffer(FID, Loc, /Invalid=*/nullptr);

	assert(LocData >= Buffer->getBufferStart() &&
	LocData < Buffer->getBufferEnd());

	const char *LineBegin = LocData - LocColumn;

	assert(LineBegin >= Buffer->getBufferStart());

	const char *LineEnd = nullptr;

	for (LineEnd = LineBegin; LineEnd != '\n' && LineEnd != '\r' &&
	LineEnd < Buffer->getBufferEnd();
	++LineEnd)
	;

	llvm::StringRef LineString(LineBegin, LineEnd - LineBegin);

	llvm::errs() << LineString << '\n';
	llvm::errs().indent(LocColumn);
	llvm::errs() << '^';
	}

	virtual void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
	const Diagnostic &Info) override {
	if (Info.hasSourceManager() && LangOpts) {
	SourceManager &SM = Info.getSourceManager();

	if (Info.getLocation().isValid()) {
	Info.getLocation().print(llvm::errs(), SM);
	llvm::errs() << ": ";
	}

	SmallString<16> DiagText;
	Info.FormatDiagnostic(DiagText);
	llvm::errs() << DiagText << '\n';

	if (Info.getLocation().isValid()) {
	PrintSourceForLocation(Info.getLocation(), SM);
	}

	for (const CharSourceRange &Range : Info.getRanges()) {
	bool Invalid = true;
	StringRef Ref = Lexer::getSourceText(Range, SM, *LangOpts, &Invalid);
	if (!Invalid) {
	llvm::errs() << Ref << '\n';
	}
	}
	}
	DiagnosticConsumer::HandleDiagnostic(DiagLevel, Info);
	}
	};

	std::unique_ptr<CompilerInstance>
	BuildCompilerInstance(ArrayRef<const char *> ClangArgv) {
	auto Ins = llvm::make_unique<CompilerInstance>();
	auto DC = llvm::make_unique<TestDiagnosticConsumer>();
	const bool ShouldOwnClient = true;
	Ins->createDiagnostics(DC.release(), ShouldOwnClient);

	auto Inv = llvm::make_unique<CompilerInvocation>();

	CompilerInvocation::CreateFromArgs(*Inv, ClangArgv.data(),
	&ClangArgv.data()[ClangArgv.size()],
	Ins->getDiagnostics());

	Inv->getLangOpts()->CPlusPlus = true;
	Inv->getLangOpts()->CPlusPlus11 = true;
	Inv->getHeaderSearchOpts().UseLibcxx = true;
	Inv->getLangOpts()->Bool = true;
	Inv->getLangOpts()->WChar = true;
	Inv->getLangOpts()->Blocks = true;
	Inv->getLangOpts()->DebuggerSupport = true;
	Inv->getLangOpts()->SpellChecking = false;
	Inv->getLangOpts()->ThreadsafeStatics = false;
	Inv->getLangOpts()->AccessControl = false;
	Inv->getLangOpts()->DollarIdents = true;
	Inv->getCodeGenOpts().setDebugInfo(codegenoptions::FullDebugInfo);
	Inv->getTargetOpts().Triple = llvm::sys::getDefaultTargetTriple();

	Ins->setInvocation(std::move(Inv));

	TargetInfo *TI = TargetInfo::CreateTargetInfo(
	Ins->getDiagnostics(), Ins->getInvocation().TargetOpts);
	Ins->setTarget(TI);
	Ins->getTarget().adjust(Ins->getLangOpts());
	Ins->createFileManager();
	Ins->createSourceManager(Ins->getFileManager());
	Ins->createPreprocessor(TU_Complete);

	return Ins;
	}

	std::unique_ptr<ASTContext>
	BuildASTContext(CompilerInstance &CI, SelectorTable &ST, Builtin::Context &BC) {
	auto AST = llvm::make_unique<ASTContext>(
	CI.getLangOpts(), CI.getSourceManager(),
	CI.getPreprocessor().getIdentifierTable(), ST, BC);
	AST->InitBuiltinTypes(CI.getTarget());
	return AST;
	}

	std::unique_ptr<CodeGenerator> BuildCodeGen(CompilerInstance &CI,
	llvm::LLVMContext &LLVMCtx) {
	StringRef ModuleName("$__module");
	return std::unique_ptr<CodeGenerator>(CreateLLVMCodeGen(
	CI.getDiagnostics(), ModuleName, CI.getHeaderSearchOpts(),
	CI.getPreprocessorOpts(), CI.getCodeGenOpts(), LLVMCtx));
	}
	} // end namespace

	namespace {
	class TestExternalASTSource : public ExternalASTSource {
	private:
	llvm::ArrayRef<std::unique_ptr<CompilerInstance>> ImportCIs;
	std::map<CompilerInstance *, std::unique_ptr<ASTImporter>> ForwardImporters;
	std::map<CompilerInstance *, std::unique_ptr<ASTImporter>> ReverseImporters;

	public:
	TestExternalASTSource(
	CompilerInstance &ExpressionCI,
	llvm::ArrayRef<std::unique_ptr<CompilerInstance>> ImportCIs)
	: ImportCIs(ImportCIs) {
	for (const std::unique_ptr<CompilerInstance> &ImportCI : ImportCIs) {
	ForwardImporters[ImportCI.get()] = llvm::make_unique<ASTImporter>(
	ExpressionCI.getASTContext(), ExpressionCI.getFileManager(),
	ImportCI->getASTContext(), ImportCI->getFileManager(),
	/MinimalImport=/true);
	ReverseImporters[ImportCI.get()] = llvm::make_unique<ASTImporter>(
	ImportCI->getASTContext(), ImportCI->getFileManager(),
	ExpressionCI.getASTContext(), ExpressionCI.getFileManager(),
	/MinimalImport=/true);
	}
	}

	bool FindExternalVisibleDeclsByName(const DeclContext *DC,
	DeclarationName Name) override {
	llvm::SmallVector<NamedDecl *, 1> Decls;

	if (isa<TranslationUnitDecl>(DC)) {
	for (const std::unique_ptr<CompilerInstance> &I : ImportCIs) {
	DeclarationName FromName = ReverseImporters[I.get()]->Import(Name);
	DeclContextLookupResult Result =
	I->getASTContext().getTranslationUnitDecl()->lookup(FromName);
	for (NamedDecl *FromD : Result) {
	NamedDecl *D =
	llvm::cast<NamedDecl>(ForwardImporters[I.get()]->Import(FromD));
	Decls.push_back(D);
	}
	}
	}
	if (Decls.empty()) {
	return false;
	} else {
	SetExternalVisibleDeclsForName(DC, Name, Decls);
	return true;
	}
	}
	};

	void AddExternalSource(
	CompilerInstance &CI,
	llvm::ArrayRef<std::unique_ptr<CompilerInstance>> Imports) {
	ASTContext &AST = CI.getASTContext();
	auto ES = llvm::make_unique<TestExternalASTSource>(CI, Imports);
	AST.setExternalSource(ES.release());
	AST.getTranslationUnitDecl()->setHasExternalVisibleStorage();
	}

	llvm::Error ParseSource(const std::string &Path, CompilerInstance &CI,
	CodeGenerator &CG) {
	SourceManager &SM = CI.getSourceManager();
	const FileEntry *FE = CI.getFileManager().getFile(Path);
	if (!FE) {
	return llvm::make_error<llvm::StringError>(
	llvm::Twine("Couldn't open ", Path), std::error_code());
	}
	SM.setMainFileID(SM.createFileID(FE, SourceLocation(), SrcMgr::C_User));
	ParseAST(CI.getPreprocessor(), &CG, CI.getASTContext());
	return llvm::Error::success();
	}

	llvm::Expected<std::unique_ptr<CompilerInstance>>
	Parse(const std::string &Path,
	llvm::ArrayRef<std::unique_ptr<CompilerInstance>> Imports) {
	std::vector<const char *> ClangArgv(ClangArgs.size());
	std::transform(ClangArgs.begin(), ClangArgs.end(), ClangArgv.begin(),
	[](const std::string &s) -> const char * { return s.data(); });
	std::unique_ptr<CompilerInstance> CI =
	init_convenience::BuildCompilerInstance(ClangArgv);
	auto ST = llvm::make_unique<SelectorTable>();
	auto BC = llvm::make_unique<Builtin::Context>();
	std::unique_ptr<ASTContext> AST =
	init_convenience::BuildASTContext(CI, ST, *BC);
	CI->setASTContext(AST.release());
	AddExternalSource(*CI, Imports);

	auto LLVMCtx = llvm::make_unique<llvm::LLVMContext>();
	std::unique_ptr<CodeGenerator> CG =
	init_convenience::BuildCodeGen(CI, LLVMCtx);
	CG->Initialize(CI->getASTContext());

	CI->getDiagnosticClient().BeginSourceFile(CI->getLangOpts(),
	&CI->getPreprocessor());
	if (llvm::Error PE = ParseSource(Path, CI, CG)) {
	return std::move(PE);
	}
	CI->getDiagnosticClient().EndSourceFile();
	if (CI->getDiagnosticClient().getNumErrors()) {
	return llvm::make_error<llvm::StringError>(
	"Errors occured while parsing the expression.", std::error_code());
	} else {
	return std::move(CI);
	}
	}
	} // end namespace

	int main(int argc, const char **argv) {
	const bool DisableCrashReporting = true;
	llvm::sys::PrintStackTraceOnErrorSignal(argv[0], DisableCrashReporting);
	llvm::cl::ParseCommandLineOptions(argc, argv);
	std::vector<std::unique_ptr<CompilerInstance>> ImportCIs;
	for (auto I : Imports) {
	llvm::Expected<std::unique_ptr<CompilerInstance>> ImportCI = Parse(I, {});
	if (auto E = ImportCI.takeError()) {
	llvm::errs() << llvm::toString(std::move(E));
	exit(-1);
	} else {
	ImportCIs.push_back(std::move(*ImportCI));
	}
	}
	llvm::Expected<std::unique_ptr<CompilerInstance>> ExpressionCI =
	Parse(Expression, ImportCIs);
	if (auto E = ExpressionCI.takeError()) {
	llvm::errs() << llvm::toString(std::move(E));
	exit(-1);
	} else {
	return 0;
	}
	}