llvm-project/clang/lib/CrossTU/CrossTranslationUnit.cpp

270 lines
10 KiB
C++

//===--- CrossTranslationUnit.cpp - -----------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the CrossTranslationUnit interface.
//
//===----------------------------------------------------------------------===//
#include "clang/CrossTU/CrossTranslationUnit.h"
#include "clang/AST/ASTImporter.h"
#include "clang/AST/Decl.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/CrossTU/CrossTUDiagnostic.h"
#include "clang/Frontend/ASTUnit.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include "clang/Frontend/TextDiagnosticPrinter.h"
#include "clang/Index/USRGeneration.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/raw_ostream.h"
#include <fstream>
#include <sstream>
namespace clang {
namespace cross_tu {
namespace {
// FIXME: This class is will be removed after the transition to llvm::Error.
class IndexErrorCategory : public std::error_category {
public:
const char *name() const noexcept override { return "clang.index"; }
std::string message(int Condition) const override {
switch (static_cast<index_error_code>(Condition)) {
case index_error_code::unspecified:
return "An unknown error has occurred.";
case index_error_code::missing_index_file:
return "The index file is missing.";
case index_error_code::invalid_index_format:
return "Invalid index file format.";
case index_error_code::multiple_definitions:
return "Multiple definitions in the index file.";
case index_error_code::missing_definition:
return "Missing definition from the index file.";
case index_error_code::failed_import:
return "Failed to import the definition.";
case index_error_code::failed_to_get_external_ast:
return "Failed to load external AST source.";
case index_error_code::failed_to_generate_usr:
return "Failed to generate USR.";
}
llvm_unreachable("Unrecognized index_error_code.");
}
};
static llvm::ManagedStatic<IndexErrorCategory> Category;
} // end anonymous namespace
char IndexError::ID;
void IndexError::log(raw_ostream &OS) const {
OS << Category->message(static_cast<int>(Code)) << '\n';
}
std::error_code IndexError::convertToErrorCode() const {
return std::error_code(static_cast<int>(Code), *Category);
}
llvm::Expected<llvm::StringMap<std::string>>
parseCrossTUIndex(StringRef IndexPath, StringRef CrossTUDir) {
std::ifstream ExternalFnMapFile(IndexPath);
if (!ExternalFnMapFile)
return llvm::make_error<IndexError>(index_error_code::missing_index_file,
IndexPath.str());
llvm::StringMap<std::string> Result;
std::string Line;
unsigned LineNo = 1;
while (std::getline(ExternalFnMapFile, Line)) {
const size_t Pos = Line.find(" ");
if (Pos > 0 && Pos != std::string::npos) {
StringRef LineRef{Line};
StringRef FunctionLookupName = LineRef.substr(0, Pos);
if (Result.count(FunctionLookupName))
return llvm::make_error<IndexError>(
index_error_code::multiple_definitions, IndexPath.str(), LineNo);
StringRef FileName = LineRef.substr(Pos + 1);
SmallString<256> FilePath = CrossTUDir;
llvm::sys::path::append(FilePath, FileName);
Result[FunctionLookupName] = FilePath.str().str();
} else
return llvm::make_error<IndexError>(
index_error_code::invalid_index_format, IndexPath.str(), LineNo);
LineNo++;
}
return Result;
}
std::string
createCrossTUIndexString(const llvm::StringMap<std::string> &Index) {
std::ostringstream Result;
for (const auto &E : Index)
Result << E.getKey().str() << " " << E.getValue() << '\n';
return Result.str();
}
CrossTranslationUnitContext::CrossTranslationUnitContext(CompilerInstance &CI)
: CI(CI), Context(CI.getASTContext()) {}
CrossTranslationUnitContext::~CrossTranslationUnitContext() {}
std::string CrossTranslationUnitContext::getLookupName(const NamedDecl *ND) {
SmallString<128> DeclUSR;
bool Ret = index::generateUSRForDecl(ND, DeclUSR); (void)Ret;
assert(!Ret && "Unable to generate USR");
return DeclUSR.str();
}
/// Recursively visits the function decls of a DeclContext, and looks up a
/// function based on USRs.
const FunctionDecl *
CrossTranslationUnitContext::findFunctionInDeclContext(const DeclContext *DC,
StringRef LookupFnName) {
assert(DC && "Declaration Context must not be null");
for (const Decl *D : DC->decls()) {
const auto *SubDC = dyn_cast<DeclContext>(D);
if (SubDC)
if (const auto *FD = findFunctionInDeclContext(SubDC, LookupFnName))
return FD;
const auto *ND = dyn_cast<FunctionDecl>(D);
const FunctionDecl *ResultDecl;
if (!ND || !ND->hasBody(ResultDecl))
continue;
if (getLookupName(ResultDecl) != LookupFnName)
continue;
return ResultDecl;
}
return nullptr;
}
llvm::Expected<const FunctionDecl *>
CrossTranslationUnitContext::getCrossTUDefinition(const FunctionDecl *FD,
StringRef CrossTUDir,
StringRef IndexName) {
assert(!FD->hasBody() && "FD has a definition in current translation unit!");
const std::string LookupFnName = getLookupName(FD);
if (LookupFnName.empty())
return llvm::make_error<IndexError>(
index_error_code::failed_to_generate_usr);
llvm::Expected<ASTUnit *> ASTUnitOrError =
loadExternalAST(LookupFnName, CrossTUDir, IndexName);
if (!ASTUnitOrError)
return ASTUnitOrError.takeError();
ASTUnit *Unit = *ASTUnitOrError;
if (!Unit)
return llvm::make_error<IndexError>(
index_error_code::failed_to_get_external_ast);
assert(&Unit->getFileManager() ==
&Unit->getASTContext().getSourceManager().getFileManager());
TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl();
if (const FunctionDecl *ResultDecl =
findFunctionInDeclContext(TU, LookupFnName))
return importDefinition(ResultDecl);
return llvm::make_error<IndexError>(index_error_code::failed_import);
}
void CrossTranslationUnitContext::emitCrossTUDiagnostics(const IndexError &IE) {
switch (IE.getCode()) {
case index_error_code::missing_index_file:
Context.getDiagnostics().Report(diag::err_fe_error_opening)
<< IE.getFileName() << "required by the CrossTU functionality";
break;
case index_error_code::invalid_index_format:
Context.getDiagnostics().Report(diag::err_fnmap_parsing)
<< IE.getFileName() << IE.getLineNum();
break;
case index_error_code::multiple_definitions:
Context.getDiagnostics().Report(diag::err_multiple_def_index)
<< IE.getLineNum();
break;
default:
break;
}
}
llvm::Expected<ASTUnit *> CrossTranslationUnitContext::loadExternalAST(
StringRef LookupName, StringRef CrossTUDir, StringRef IndexName) {
// FIXME: The current implementation only supports loading functions with
// a lookup name from a single translation unit. If multiple
// translation units contains functions with the same lookup name an
// error will be returned.
ASTUnit *Unit = nullptr;
auto FnUnitCacheEntry = FunctionASTUnitMap.find(LookupName);
if (FnUnitCacheEntry == FunctionASTUnitMap.end()) {
if (FunctionFileMap.empty()) {
SmallString<256> IndexFile = CrossTUDir;
if (llvm::sys::path::is_absolute(IndexName))
IndexFile = IndexName;
else
llvm::sys::path::append(IndexFile, IndexName);
llvm::Expected<llvm::StringMap<std::string>> IndexOrErr =
parseCrossTUIndex(IndexFile, CrossTUDir);
if (IndexOrErr)
FunctionFileMap = *IndexOrErr;
else
return IndexOrErr.takeError();
}
auto It = FunctionFileMap.find(LookupName);
if (It == FunctionFileMap.end())
return llvm::make_error<IndexError>(index_error_code::missing_definition);
StringRef ASTFileName = It->second;
auto ASTCacheEntry = FileASTUnitMap.find(ASTFileName);
if (ASTCacheEntry == FileASTUnitMap.end()) {
IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
TextDiagnosticPrinter *DiagClient =
new TextDiagnosticPrinter(llvm::errs(), &*DiagOpts);
IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
new DiagnosticsEngine(DiagID, &*DiagOpts, DiagClient));
std::unique_ptr<ASTUnit> LoadedUnit(ASTUnit::LoadFromASTFile(
ASTFileName, CI.getPCHContainerOperations()->getRawReader(),
ASTUnit::LoadEverything, Diags, CI.getFileSystemOpts()));
Unit = LoadedUnit.get();
FileASTUnitMap[ASTFileName] = std::move(LoadedUnit);
} else {
Unit = ASTCacheEntry->second.get();
}
FunctionASTUnitMap[LookupName] = Unit;
} else {
Unit = FnUnitCacheEntry->second;
}
return Unit;
}
llvm::Expected<const FunctionDecl *>
CrossTranslationUnitContext::importDefinition(const FunctionDecl *FD) {
ASTImporter &Importer = getOrCreateASTImporter(FD->getASTContext());
auto *ToDecl =
cast<FunctionDecl>(Importer.Import(const_cast<FunctionDecl *>(FD)));
assert(ToDecl->hasBody());
assert(FD->hasBody() && "Functions already imported should have body.");
return ToDecl;
}
ASTImporter &
CrossTranslationUnitContext::getOrCreateASTImporter(ASTContext &From) {
auto I = ASTUnitImporterMap.find(From.getTranslationUnitDecl());
if (I != ASTUnitImporterMap.end())
return *I->second;
ASTImporter *NewImporter =
new ASTImporter(Context, Context.getSourceManager().getFileManager(),
From, From.getSourceManager().getFileManager(), false);
ASTUnitImporterMap[From.getTranslationUnitDecl()].reset(NewImporter);
return *NewImporter;
}
} // namespace cross_tu
} // namespace clang