llvm/llvm/tools/llvm-exegesis/lib/SubprocessMemory.cpp

//===-- SubprocessMemory.cpp ------------------------------------*- 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
//
//===----------------------------------------------------------------------===//

#include "SubprocessMemory.h"
#include "Error.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/FormatVariadic.h"
#include <cerrno>

#ifdef __linux__
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <unistd.h>
#endif

namespace llvm {
namespace exegesis {

#if defined(__linux__)

// The SYS_* macros for system calls are provided by the libc whereas the
// __NR_* macros are from the linux headers. This means that sometimes
// SYS_* macros might not be available for certain system calls depending
// upon the libc. This happens with the gettid syscall and bionic for
// example, so we use __NR_gettid when no SYS_gettid is available.
#ifndef SYS_gettid
#define SYS_gettid …
#endif

long SubprocessMemory::getCurrentTID() { … }

#if !defined(__ANDROID__)

Error SubprocessMemory::initializeSubprocessMemory(pid_t ProcessID) { … }

Error SubprocessMemory::addMemoryDefinition(
    std::unordered_map<std::string, MemoryValue> MemoryDefinitions,
    pid_t ProcessPID) { … }

Expected<int> SubprocessMemory::setupAuxiliaryMemoryInSubprocess(
    std::unordered_map<std::string, MemoryValue> MemoryDefinitions,
    pid_t ParentPID, long ParentTID, int CounterFileDescriptor) { … }

SubprocessMemory::~SubprocessMemory() { … }

#else

Error SubprocessMemory::initializeSubprocessMemory(pid_t ProcessPID) {
  return make_error<Failure>(
      "initializeSubprocessMemory is only supported on Linux");
}

Error SubprocessMemory::addMemoryDefinition(
    std::unordered_map<std::string, MemoryValue> MemoryDefinitions,
    pid_t ProcessPID) {
  return make_error<Failure>("addMemoryDefinitions is only supported on Linux");
}

Expected<int> SubprocessMemory::setupAuxiliaryMemoryInSubprocess(
    std::unordered_map<std::string, MemoryValue> MemoryDefinitions,
    pid_t ParentPID, long ParentTID, int CounterFileDescriptor) {
  return make_error<Failure>(
      "setupAuxiliaryMemoryInSubprocess is only supported on Linux");
}

SubprocessMemory::~SubprocessMemory() {}

#endif // !defined(__ANDROID__)
#endif // defined(__linux__)

} // namespace exegesis
} // namespace llvm