【.NET8】访问私有成员新姿势UnsafeAccessor（下）

using System.Linq.Expressions;
 
using System.Reflection;
 
using System.Reflection.Emit;
 
using System.Runtime.CompilerServices;
 
using BenchmarkDotNet.Attributes;
 
using BenchmarkDotNet.Columns;
 
using BenchmarkDotNet.Configs;
 
using BenchmarkDotNet.Order;
 
using BenchmarkDotNet.Reports;
 
using BenchmarkDotNet.Running;
 
using Perfolizer.Horology;
 

 
[MemoryDiagnoser]
 
[Orderer(SummaryOrderPolicy.FastestToSlowest)]
 
public class AccessBenchmarks
 
{
 
 public static readonly A TestInstance = new();
 
 public static readonly Action<A, int> SetDelegate;
 
 public static readonly Func<A, int> GetDelegate;
 
 public static readonly PropertyInfo ValueProperty;
 
 public static readonly MethodInfo SetValueMethod;
 
 public static readonly MethodInfo GetValueMethod;
 

 
 public static readonly Func<A, int> GetValueExpressionFunc;
 
 public static readonly Action<A, int> SetValueExpressionAction;
 

 
 static AccessBenchmarks()
 
 {
 
 TestInstance = new();
 
 ValueProperty = typeof(A).GetProperty("Value");
 
 SetValueMethod = ValueProperty.GetSetMethod();
 
 GetValueMethod = ValueProperty.GetGetMethod();
 

 
 SetDelegate = CreateSetDelegate();
 
 GetDelegate = CreateGetDelegate();
 

 
 GetValueExpressionFunc = CreateGetValueExpressionFunc();
 
 SetValueExpressionAction = CreateSetValueExpressionAction();
 
 }
 

 
 [UnsafeAccessor(UnsafeAccessorKind.Method, Name = "get_Value")]
 
 static extern int GetValueUnsafe(A a);
 

 
 [UnsafeAccessor(UnsafeAccessorKind.Method, Name = "set_Value")]
 
 static extern void SetValueUnsafe(A a, int value);
 

 
 [Benchmark]
 
 public void UnsafeAccessor()
 
 {
 
 SetValueUnsafe(TestInstance, 10);
 
 var value = GetValueUnsafe(TestInstance);
 
 }
 

 
 [Benchmark]
 
 public void Reflection()
 
 {
 
 SetValueMethod.Invoke(TestInstance, new object[] { 10 });
 
 var value = GetValueMethod.Invoke(TestInstance, new object[] { });
 
 }
 

 
 [Benchmark]
 
 public void Emit()
 
 {
 
 SetDelegate(TestInstance, 10);
 
 var value = GetDelegate(TestInstance);
 
 }
 

 
 [Benchmark]
 
 public void ExpressionTrees()
 
 {
 
 SetValueExpressionAction(TestInstance, 10);
 
 var value = GetValueExpressionFunc(TestInstance);
 
 }
 

 
 [Benchmark]
 
 public void Direct()
 
 {
 
 TestInstance.Value = 10;
 
 var value = TestInstance.Value;
 
 }
 

 
 private static Action<A, int> CreateSetDelegate()
 
 {
 
 var dynamicMethod = new DynamicMethod("SetValue", null, new[] { typeof(A), typeof(int) }, typeof(A));
 
 var ilGenerator = dynamicMethod.GetILGenerator();
 
        ilGenerator.Emit(OpCodes.Ldarg_0);
 
        ilGenerator.Emit(OpCodes.Ldarg_1);
 
        ilGenerator.EmitCall(OpCodes.Call, SetValueMethod, null);
 
        ilGenerator.Emit(OpCodes.Ret);
 
 return (Action<A, int>)dynamicMethod.CreateDelegate(typeof(Action<A, int>));
 
 }
 

 
 private static Func<A, int> CreateGetDelegate()
 
 {
 
 var dynamicMethod = new DynamicMethod("GetValue", typeof(int), new[] { typeof(A) }, typeof(A));
 
 var ilGenerator = dynamicMethod.GetILGenerator();
 
        ilGenerator.Emit(OpCodes.Ldarg_0);
 
        ilGenerator.EmitCall(OpCodes.Call, GetValueMethod, null);
 
        ilGenerator.Emit(OpCodes.Ret);
 
 return (Func<A, int>)dynamicMethod.CreateDelegate(typeof(Func<A, int>));
 
 }
 

 
 private static Func<A, int> CreateGetValueExpressionFunc()
 
 {
 
 var instance = Expression.Parameter(typeof(A), "instance");
 
 var getValueExpression = Expression.Lambda<Func<A, int>>(
 
 Expression.Property(instance, ValueProperty),
 
            instance);
 

 
 return getValueExpression.Compile();
 
 }
 

 
 private static Action<A, int> CreateSetValueExpressionAction()
 
 {
 
 var instance = Expression.Parameter(typeof(A), "instance");
 
 var value = Expression.Parameter(typeof(int), "value");
 
 var setValueExpression = Expression.Lambda<Action<A, int>>(
 
 Expression.Call(instance, ValueProperty.GetSetMethod(true), value),
 
            instance, value);
 

 
 return setValueExpression.Compile();
 
 }
 
}
 

 
public class A
 
{
 
 public int Value { get; set; }
 
}
 

 
public class Program
 
{
 
 public static void Main()
 
 {
 
 Console.WriteLine(AccessBenchmarks.TestInstance);
 
 var summary = BenchmarkRunner.Run<AccessBenchmarks>(DefaultConfig.Instance.WithSummaryStyle(new SummaryStyle(
 
            cultureInfo: null, // use default
 
            printUnitsInHeader: true,
 
            printUnitsInContent: true,
 
            sizeUnit: SizeUnit.B,
 
            timeUnit: TimeUnit.Nanosecond,
 
            printZeroValuesInContent: true,
 
            ratioStyle: RatioStyle.Trend // this will print the ratio column
 
 )));
 
 }
 
}