llvm/llvm/include/llvm/ExecutionEngine/Orc/ExecutionUtils.h

//===- ExecutionUtils.h - Utilities for executing code in Orc ---*- 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
//
//===----------------------------------------------------------------------===//
//
// Contains utilities for executing code in Orc.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H
#define LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H

#include "llvm/ADT/iterator_range.h"
#include "llvm/ExecutionEngine/JITSymbol.h"
#include "llvm/ExecutionEngine/Orc/Core.h"
#include "llvm/ExecutionEngine/Orc/Mangling.h"
#include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
#include "llvm/ExecutionEngine/Orc/Shared/OrcError.h"
#include "llvm/ExecutionEngine/RuntimeDyld.h"
#include "llvm/Object/Archive.h"
#include "llvm/Support/DynamicLibrary.h"
#include <algorithm>
#include <cstdint>
#include <utility>
#include <vector>

namespace llvm {

class ConstantArray;
class GlobalVariable;
class Function;
class Module;
class Value;

namespace object {
class MachOUniversalBinary;
}

namespace orc {

class ObjectLayer;

/// This iterator provides a convenient way to iterate over the elements
///        of an llvm.global_ctors/llvm.global_dtors instance.
///
///   The easiest way to get hold of instances of this class is to use the
/// getConstructors/getDestructors functions.
class CtorDtorIterator { … };

/// Create an iterator range over the entries of the llvm.global_ctors
///        array.
iterator_range<CtorDtorIterator> getConstructors(const Module &M);

/// Create an iterator range over the entries of the llvm.global_ctors
///        array.
iterator_range<CtorDtorIterator> getDestructors(const Module &M);

/// This iterator provides a convenient way to iterate over GlobalValues that
/// have initialization effects.
class StaticInitGVIterator { … };

/// Create an iterator range over the GlobalValues that contribute to static
/// initialization.
inline iterator_range<StaticInitGVIterator> getStaticInitGVs(Module &M) { … }

class CtorDtorRunner { … };

/// Support class for static dtor execution. For hosted (in-process) JITs
///        only!
///
///   If a __cxa_atexit function isn't found C++ programs that use static
/// destructors will fail to link. However, we don't want to use the host
/// process's __cxa_atexit, because it will schedule JIT'd destructors to run
/// after the JIT has been torn down, which is no good. This class makes it easy
/// to override __cxa_atexit (and the related __dso_handle).
///
///   To use, clients should manually call searchOverrides from their symbol
/// resolver. This should generally be done after attempting symbol resolution
/// inside the JIT, but before searching the host process's symbol table. When
/// the client determines that destructors should be run (generally at JIT
/// teardown or after a return from main), the runDestructors method should be
/// called.
class LocalCXXRuntimeOverridesBase { … };

class LocalCXXRuntimeOverrides : public LocalCXXRuntimeOverridesBase { … };

/// An interface for Itanium __cxa_atexit interposer implementations.
class ItaniumCXAAtExitSupport { … };

/// A utility class to expose symbols found via dlsym to the JIT.
///
/// If an instance of this class is attached to a JITDylib as a fallback
/// definition generator, then any symbol found in the given DynamicLibrary that
/// passes the 'Allow' predicate will be added to the JITDylib.
class DynamicLibrarySearchGenerator : public DefinitionGenerator { … };

/// A utility class to expose symbols from a static library.
///
/// If an instance of this class is attached to a JITDylib as a fallback
/// definition generator, then any symbol found in the archive will result in
/// the containing object being added to the JITDylib.
class StaticLibraryDefinitionGenerator : public DefinitionGenerator { … };

/// A utility class to create COFF dllimport GOT symbols (__imp_*) and PLT
/// stubs.
///
/// If an instance of this class is attached to a JITDylib as a fallback
/// definition generator, PLT stubs and dllimport __imp_ symbols will be
/// generated for external symbols found outside the given jitdylib. Currently
/// only supports x86_64 architecture.
class DLLImportDefinitionGenerator : public DefinitionGenerator { … };

} // end namespace orc
} // end namespace llvm

#endif // LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H