benchmark_executable = []
benchmark_mpi_launcher = ''

if get_option('build_benchmarks')
  if is_wasm
    error('build_benchmarks requires a native target; use the web demo for Emscripten')
  endif
  if not mfem_has_mpi
    error('build_benchmarks requires -Dmfem_mpi=enabled (and therefore Hypre)')
  endif

  benchmark_accelerator_deps = []
  if mfem_has_cuda
    benchmark_nvcc = dependency_has_nvcc ? (
      dependency_prefix / 'bin' / 'nvcc'
    ) : nvcc_program.full_path()
    benchmark_cuda_root_result = run_command(
      python_build,
      '-c',
      'import os, sys; print(os.path.dirname(os.path.dirname(os.path.realpath(sys.argv[1]))))',
      benchmark_nvcc,
      check: true,
    )
    benchmark_cuda_root = benchmark_cuda_root_result.stdout().strip()
    benchmark_accelerator_deps += [cpp.find_library(
      'cudart',
      dirs: [
        benchmark_cuda_root / 'lib64',
        benchmark_cuda_root / 'lib',
        benchmark_cuda_root / 'lib' / 'x64',
        benchmark_cuda_root / 'targets' / 'x86_64-linux' / 'lib',
        benchmark_cuda_root / 'targets' / 'aarch64-linux' / 'lib',
        benchmark_cuda_root / 'targets' / 'ppc64le-linux' / 'lib',
      ],
      required: true,
    )]
  endif
  if mfem_has_hip
    benchmark_hipcc = dependency_has_hipcc ? (
      dependency_prefix / 'bin' / 'hipcc'
    ) : hipcc_program.full_path()
    benchmark_hip_root_result = run_command(
      python_build,
      '-c',
      'import os, sys; print(os.path.dirname(os.path.dirname(os.path.realpath(sys.argv[1]))))',
      benchmark_hipcc,
      check: true,
    )
    benchmark_hip_root = benchmark_hip_root_result.stdout().strip()
    benchmark_accelerator_deps += [cpp.find_library(
      'amdhip64',
      dirs: [benchmark_hip_root / 'lib', benchmark_hip_root / 'lib64'],
      required: true,
    )]
  endif

  benchmark_build_rpath = mfem_runtime_prefix == '' ? '' : mfem_runtime_prefix / 'lib'
  benchmark_install_rpath = ''
  if mfem_runtime_prefix != '' and not is_windows
    benchmark_install_rpath = host_machine.system() == 'darwin' ? '@loader_path/../lib' : '$ORIGIN/../lib'
  endif

  benchmark_executable = executable(
    'mfem-backend-benchmark',
    'backend_operator.cpp',
    dependencies: [mfem_dep, template_include_dep] + benchmark_accelerator_deps,
    override_options: ['cpp_std=' + mfem_consumer_cpp_std],
    build_rpath: benchmark_build_rpath,
    install_rpath: benchmark_install_rpath,
    install: true,
    install_tag: 'benchmarks',
  )

  if mpi_launcher_from_dependency and not wheel_carries_native_bundle
    benchmark_launcher_program = find_program(
      dependency_prefix / 'bin' / 'mpiexec',
      dependency_prefix / 'bin' / 'mpirun',
      required: true,
    )
    benchmark_mpi_launcher = benchmark_launcher_program.full_path()
  elif mfem_runtime_prefix != ''
    benchmark_mpi_launcher = mfem_runtime_prefix / 'bin' / 'mpiexec'
  else
    benchmark_launcher_program = find_program('mpiexec', 'mpirun', required: true)
    benchmark_mpi_launcher = benchmark_launcher_program.full_path()
  endif

  benchmark_cases = ['cpu']
  if mfem_features.get('ceed')
    benchmark_cases += ['ceed-cpu']
  endif
  if mfem_has_openmp
    benchmark_cases += ['omp']
  endif
  benchmark_cases += ['mpi']
  if mfem_has_cuda
    benchmark_cases += ['cuda']
    if mfem_features.get('ceed')
      benchmark_cases += ['ceed-cuda']
    endif
  endif

  benchmark_environment = environment()
  if (
    mfem_runtime_prefix != '' and dependency_prefix != '' and
    not wheel_carries_native_bundle
  )
    benchmark_environment.prepend('PATH', dependency_prefix / 'bin')
    if host_machine.system() == 'darwin'
      benchmark_environment.prepend('DYLD_LIBRARY_PATH', dependency_prefix / 'lib64')
      benchmark_environment.prepend('DYLD_LIBRARY_PATH', dependency_prefix / 'lib')
    elif not is_windows
      benchmark_environment.prepend('LD_LIBRARY_PATH', dependency_prefix / 'lib64')
      benchmark_environment.prepend('LD_LIBRARY_PATH', dependency_prefix / 'lib')
    endif
  endif
  if mfem_runtime_prefix != ''
    benchmark_environment.prepend('PATH', mfem_runtime_prefix / 'bin')
    if host_machine.system() == 'darwin'
      benchmark_environment.prepend('DYLD_LIBRARY_PATH', mfem_runtime_prefix / 'lib64')
      benchmark_environment.prepend('DYLD_LIBRARY_PATH', mfem_runtime_prefix / 'lib')
    elif not is_windows
      benchmark_environment.prepend('LD_LIBRARY_PATH', mfem_runtime_prefix / 'lib64')
      benchmark_environment.prepend('LD_LIBRARY_PATH', mfem_runtime_prefix / 'lib')
    endif
  endif

  benchmark(
    'mfem-backend-comparison',
    python_build,
    args: [
      files('../tools/run_backend_benchmarks.py'),
      '--executable', benchmark_executable,
      '--launcher', benchmark_mpi_launcher,
      '--cases', ','.join(benchmark_cases),
      '--output-dir', meson.current_build_dir(),
    ],
    depends: benchmark_executable,
    env: benchmark_environment,
    timeout: 3600,
  )
endif