llvm/clang/include/clang/CrossTU/CrossTranslationUnit.h

//===--- CrossTranslationUnit.h - -------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
//  This file provides an interface to load binary AST dumps on demand. This
//  feature can be utilized for tools that require cross translation unit
//  support.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_CROSSTU_CROSSTRANSLATIONUNIT_H
#define LLVM_CLANG_CROSSTU_CROSSTRANSLATIONUNIT_H

#include "clang/AST/ASTImporterSharedState.h"
#include "clang/Analysis/MacroExpansionContext.h"
#include "clang/Basic/LLVM.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/Path.h"
#include <optional>

namespace clang {
class CompilerInstance;
class ASTContext;
class ASTImporter;
class ASTUnit;
class DeclContext;
class FunctionDecl;
class VarDecl;
class NamedDecl;
class TranslationUnitDecl;

namespace cross_tu {

enum class index_error_code { … };

class IndexError : public llvm::ErrorInfo<IndexError> { … };

/// This function parses an index file that determines which
/// translation unit contains which definition. The IndexPath is not prefixed
/// with CTUDir, so an absolute path is expected for consistent results.
///
/// The index file format is the following:
/// each line consists of an USR and a filepath separated by a space.
///
/// \return Returns a map where the USR is the key and the filepath is the value
///         or an error.
llvm::Expected<llvm::StringMap<std::string>>
parseCrossTUIndex(StringRef IndexPath);

std::string createCrossTUIndexString(const llvm::StringMap<std::string> &Index);

InvocationListTy;
/// Parse the YAML formatted invocation list file content \p FileContent.
/// The format is expected to be a mapping from absolute source file
/// paths in the filesystem to a list of command-line parts, which
/// constitute the invocation needed to compile that file. That invocation
/// will be used to produce the AST of the TU.
llvm::Expected<InvocationListTy> parseInvocationList(
    StringRef FileContent,
    llvm::sys::path::Style PathStyle = llvm::sys::path::Style::posix);

/// Returns true if it makes sense to import a foreign variable definition.
/// For instance, we don't want to import variables that have non-trivial types
/// because the constructor might have side-effects.
bool shouldImport(const VarDecl *VD, const ASTContext &ACtx);

/// This class is used for tools that requires cross translation
///        unit capability.
///
/// This class can load definitions from external AST sources.
/// The loaded definition will be merged back to the original AST using the
/// AST Importer.
/// In order to use this class, an index file is required that describes
/// the locations of the AST files for each definition.
///
/// Note that this class also implements caching.
class CrossTranslationUnitContext { … };

} // namespace cross_tu
} // namespace clang

#endif // LLVM_CLANG_CROSSTU_CROSSTRANSLATIONUNIT_H