new_contents: """
  Benchmarking and performance tests.
  """
  import pytest
  
  from pluggy import _MultiCall, HookImpl
  from pluggy import HookspecMarker, HookimplMarker
  
  
  hookspec = HookspecMarker("example")
  hookimpl = HookimplMarker("example")
  
  
  def MC(methods, kwargs, firstresult=False):
      hookfuncs = []
      for method in methods:
          f = HookImpl(None, "<temp>", method, method.example_impl)
          hookfuncs.append(f)
      return _MultiCall(hookfuncs, kwargs, {"firstresult": firstresult})
  
  
  @hookimpl(hookwrapper=True)
  def m1(arg1, arg2, arg3):
      yield
  
  
  @hookimpl
  def m2(arg1, arg2, arg3):
      return arg1, arg2, arg3
  
  
  @hookimpl(hookwrapper=True)
  def w1(arg1, arg2, arg3):
      yield
  
  
  @hookimpl(hookwrapper=True)
  def w2(arg1, arg2, arg3):
      yield
  
  
  def inner_exec(methods):
      return MC(methods, {'arg1': 1, 'arg2': 2, 'arg3': 3}).execute()
  
  
  @pytest.mark.benchmark
  def test_hookimpls_speed(benchmark):
      benchmark(inner_exec, [m1, m2])
  
  
  @pytest.mark.benchmark
  def test_hookwrappers_speed(benchmark):
      benchmark(inner_exec, [w1, w2])
  
  
  @pytest.mark.benchmark
  def test_impls_and_wrappers_speed(benchmark):
      benchmark(inner_exec, [m1, m2, w1, w2])
  
subject: Add a baseline set of _MultiCall performance tests