public static IComparer <T> Compile <T>(AssemblyEmitter assembly, Type objectType, Property[] props)
{
var typeBuilder = assembly.DefineType(
"__distinct",
TypeAttributes.Public,
typeof(object)
);
{
var ctor = typeBuilder.DefineConstructor(
MethodAttributes.Public,
CallingConventions.Standard,
Type.EmptyTypes
);
var il = ctor.GetILGenerator();
// : base()
il.Emit(OpCodes.Ldarg_0);
il.Emit(
OpCodes.Call,
typeof(T).GetConstructor(Type.EmptyTypes) ??
throw new Exception($"Could not find empty constructor for type {typeof(T).FullName}")
);
// return;
il.Emit(OpCodes.Ret);
}
typeBuilder.AddInterfaceImplementation(typeof(IComparer <T>));
MethodBuilder compareMethod;
{
var emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "Compare",
/* attr */
MethodAttributes.Public | MethodAttributes.Virtual,
/* return */
typeof(int),
/* params */
new[] { typeof(T), typeof(T) }
);
var a = emitter.CreateLocal(objectType);
var b = emitter.CreateLocal(objectType);
var v = emitter.CreateLocal(typeof(int));
emitter.LoadArgument(1);
emitter.CastAs(objectType);
emitter.StoreLocal(a);
emitter.LoadArgument(2);
emitter.CastAs(objectType);
emitter.StoreLocal(b);
emitter.Load(0);
emitter.StoreLocal(v);
var end = emitter.CreateLabel();
for (var i = 0; i < props.Length; ++i)
{
if (i > 0)
{
emitter.LoadLocal(v);
emitter.BranchIfTrue(end);
}
var prop = props[i];
emitter.LoadLocal(a);
emitter.Chain(prop);
var couldCompare =
emitter.CompareTo(
1,
() =>
{
emitter.LoadLocal(b);
emitter.Chain(prop);
}
);
if (!couldCompare)
{
throw new InvalidOperationException("Property is not comparable.");
}
emitter.StoreLocal(v);
}
emitter.MarkLabel(end);
emitter.LoadLocal(v);
emitter.Return();
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IComparer <T>).GetMethod(
"Compare",
new[]
{
typeof(T),
typeof(T)
}
) ?? throw new Exception($"No Compare method found for type {typeof(T).FullName}")
);
compareMethod = emitter.Method;
}
typeBuilder.AddInterfaceImplementation(typeof(IEqualityComparer <T>));
{
var emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "Equals",
/* attr */
MethodAttributes.Public | MethodAttributes.Virtual,
/* return */
typeof(bool),
/* params */
new[] { typeof(T), typeof(T) }
);
emitter.Generator.Emit(OpCodes.Ldarg_0);
emitter.Generator.Emit(OpCodes.Ldarg_1);
emitter.Generator.Emit(OpCodes.Ldarg_2);
emitter.Generator.Emit(OpCodes.Call, compareMethod);
emitter.Generator.Emit(OpCodes.Ldc_I4_0);
emitter.Generator.Emit(OpCodes.Ceq);
emitter.Generator.Emit(OpCodes.Ret);
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IEqualityComparer <T>).GetMethod(
"Equals",
new[]
{
typeof(T),
typeof(T)
}
) ?? throw new Exception($"No Equals method found for type {typeof(T).FullName}")
);
}
{
var emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "GetHashCode",
/* attr */
MethodAttributes.Public | MethodAttributes.Virtual,
/* return */
typeof(int),
/* params */
new[] { typeof(T) }
);
var obj = emitter.CreateLocal(objectType);
emitter.LoadArgument(1);
emitter.CastAs(objectType);
emitter.StoreLocal(obj);
for (var i = 0; i < props.Length; ++i)
{
var prop = props[i];
emitter.LoadLocal(obj);
emitter.Chain(prop);
var active = emitter.Active;
var getHashCode = active.GetMethod("GetHashCode", Type.EmptyTypes);
getHashCode ??= typeof(T).GetMethod("GetHashCode", Type.EmptyTypes);
if (active != typeof(int))
{
if (!active.IsValueType)
{
var value = emitter.AcquireTemp(active);
var valueNotNull = emitter.CreateLabel();
var done = emitter.CreateLabel();
emitter.StoreLocal(value);
emitter.LoadLocal(value);
emitter.BranchIfTrue(valueNotNull);
emitter.Load(0);
emitter.Pop(typeof(int));
emitter.Branch(done);
emitter.MarkLabel(valueNotNull);
emitter.LoadLocal(value);
emitter.Call(getHashCode);
emitter.ReleaseTemp(value);
emitter.MarkLabel(done);
}
else
{
emitter.Call(getHashCode);
}
}
if (i > 0)
{
emitter.Xor();
}
}
emitter.Return();
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IEqualityComparer <T>).GetMethod(
"GetHashCode",
new[]
{
typeof(T)
}
) ?? throw new Exception($"No GetHashCode method found for type {typeof(T).FullName}")
);
}
var comparerType = typeBuilder.CreateType();
return(comparerType.CreateInstance <IComparer <T> >());
}
public static IComparer Compile(AssemblyEmitter assembly, Type objectType, Property[] props)
{
TypeBuilder typeBuilder = assembly.DefineType(
"__distinct",
TypeAttributes.Public,
typeof(object)
);
#region Constructor
{
ConstructorBuilder ctor = typeBuilder.DefineConstructor(
MethodAttributes.Public,
CallingConventions.Standard,
Type.EmptyTypes
);
ILGenerator il = ctor.GetILGenerator();
// : base()
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Call, typeof(object).GetConstructor(Type.EmptyTypes));
// return;
il.Emit(OpCodes.Ret);
}
#endregion
#region IComparer
typeBuilder.AddInterfaceImplementation(typeof(IComparer));
MethodBuilder compareMethod;
#region Compare
{
MethodEmitter emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "Compare",
/* attr */ MethodAttributes.Public | MethodAttributes.Virtual,
/* return */ typeof(int),
/* params */ new Type[] { typeof(object), typeof(object) });
LocalBuilder a = emitter.CreateLocal(objectType);
LocalBuilder b = emitter.CreateLocal(objectType);
LocalBuilder v = emitter.CreateLocal(typeof(int));
emitter.LoadArgument(1);
emitter.CastAs(objectType);
emitter.StoreLocal(a);
emitter.LoadArgument(2);
emitter.CastAs(objectType);
emitter.StoreLocal(b);
emitter.Load(0);
emitter.StoreLocal(v);
Label end = emitter.CreateLabel();
for (int i = 0; i < props.Length; ++i)
{
if (i > 0)
{
emitter.LoadLocal(v);
emitter.BranchIfTrue(end); // if ( v != 0 ) return v;
}
Property prop = props[i];
emitter.LoadLocal(a);
emitter.Chain(prop);
bool couldCompare =
emitter.CompareTo(1, delegate()
{
emitter.LoadLocal(b);
emitter.Chain(prop);
});
if (!couldCompare)
{
throw new InvalidOperationException("Property is not comparable.");
}
emitter.StoreLocal(v);
}
emitter.MarkLabel(end);
emitter.LoadLocal(v);
emitter.Return();
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IComparer).GetMethod(
"Compare",
new Type[]
{
typeof(object),
typeof(object)
}
)
);
compareMethod = emitter.Method;
}
#endregion
#endregion
#region IEqualityComparer
typeBuilder.AddInterfaceImplementation(typeof(IEqualityComparer <object>));
#region Equals
{
MethodEmitter emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "Equals",
/* attr */ MethodAttributes.Public | MethodAttributes.Virtual,
/* return */ typeof(bool),
/* params */ new Type[] { typeof(object), typeof(object) });
emitter.Generator.Emit(OpCodes.Ldarg_0);
emitter.Generator.Emit(OpCodes.Ldarg_1);
emitter.Generator.Emit(OpCodes.Ldarg_2);
emitter.Generator.Emit(OpCodes.Call, compareMethod);
emitter.Generator.Emit(OpCodes.Ldc_I4_0);
emitter.Generator.Emit(OpCodes.Ceq);
emitter.Generator.Emit(OpCodes.Ret);
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IEqualityComparer <object>).GetMethod(
"Equals",
new Type[]
{
typeof(object),
typeof(object)
}
)
);
}
#endregion
#region GetHashCode
{
MethodEmitter emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "GetHashCode",
/* attr */ MethodAttributes.Public | MethodAttributes.Virtual,
/* return */ typeof(int),
/* params */ new Type[] { typeof(object) });
LocalBuilder obj = emitter.CreateLocal(objectType);
emitter.LoadArgument(1);
emitter.CastAs(objectType);
emitter.StoreLocal(obj);
for (int i = 0; i < props.Length; ++i)
{
Property prop = props[i];
emitter.LoadLocal(obj);
emitter.Chain(prop);
Type active = emitter.Active;
MethodInfo getHashCode = active.GetMethod("GetHashCode", Type.EmptyTypes);
if (getHashCode == null)
{
getHashCode = typeof(object).GetMethod("GetHashCode", Type.EmptyTypes);
}
if (active != typeof(int))
{
if (!active.IsValueType)
{
LocalBuilder value = emitter.AcquireTemp(active);
Label valueNotNull = emitter.CreateLabel();
Label done = emitter.CreateLabel();
emitter.StoreLocal(value);
emitter.LoadLocal(value);
emitter.BranchIfTrue(valueNotNull);
emitter.Load(0);
emitter.Pop(typeof(int));
emitter.Branch(done);
emitter.MarkLabel(valueNotNull);
emitter.LoadLocal(value);
emitter.Call(getHashCode);
emitter.ReleaseTemp(value);
emitter.MarkLabel(done);
}
else
{
emitter.Call(getHashCode);
}
}
if (i > 0)
{
emitter.Xor();
}
}
emitter.Return();
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IEqualityComparer <object>).GetMethod(
"GetHashCode",
new Type[]
{
typeof(object)
}
)
);
}
#endregion
#endregion
Type comparerType = typeBuilder.CreateType();
return((IComparer)Activator.CreateInstance(comparerType));
}
public static IComparer Compile(AssemblyEmitter assembly, Type objectType, Property[] props)
{
TypeBuilder typeBuilder = assembly.DefineType(
"__distinct",
TypeAttributes.Public,
typeof(object));
#region Constructor
{
ConstructorBuilder ctor = typeBuilder.DefineConstructor(
MethodAttributes.Public,
CallingConventions.Standard,
Type.EmptyTypes);
ILGenerator il = ctor.GetILGenerator();
// : base()
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Call, typeof(object).GetConstructor(Type.EmptyTypes));
// return;
il.Emit(OpCodes.Ret);
}
#endregion
#region IComparer
typeBuilder.AddInterfaceImplementation(typeof(IComparer));
MethodBuilder compareMethod;
#region Compare
{
MethodEmitter emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "Compare",
/* attr */ MethodAttributes.Public | MethodAttributes.Virtual,
/* return */ typeof(int),
/* params */ new Type[] { typeof(object), typeof(object) });
LocalBuilder a = emitter.CreateLocal(objectType);
LocalBuilder b = emitter.CreateLocal(objectType);
LocalBuilder v = emitter.CreateLocal(typeof(int));
emitter.LoadArgument(1);
emitter.CastAs(objectType);
emitter.StoreLocal(a);
emitter.LoadArgument(2);
emitter.CastAs(objectType);
emitter.StoreLocal(b);
emitter.Load(0);
emitter.StoreLocal(v);
Label end = emitter.CreateLabel();
for (int i = 0; i < props.Length; ++i)
{
if (i > 0)
{
emitter.LoadLocal(v);
emitter.BranchIfTrue(end); // if ( v != 0 ) return v;
}
Property prop = props[i];
emitter.LoadLocal(a);
emitter.Chain(prop);
bool couldCompare =
emitter.CompareTo(1, delegate()
{
emitter.LoadLocal(b);
emitter.Chain(prop);
});
if (!couldCompare)
throw new InvalidOperationException("Property is not comparable.");
emitter.StoreLocal(v);
}
emitter.MarkLabel(end);
emitter.LoadLocal(v);
emitter.Return();
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IComparer).GetMethod(
"Compare",
new Type[]
{
typeof(object),
typeof(object)
}));
compareMethod = emitter.Method;
}
#endregion
#endregion
#region IEqualityComparer
typeBuilder.AddInterfaceImplementation(typeof(IEqualityComparer<object>));
#region Equals
{
MethodEmitter emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "Equals",
/* attr */ MethodAttributes.Public | MethodAttributes.Virtual,
/* return */ typeof(bool),
/* params */ new Type[] { typeof(object), typeof(object) });
emitter.Generator.Emit(OpCodes.Ldarg_0);
emitter.Generator.Emit(OpCodes.Ldarg_1);
emitter.Generator.Emit(OpCodes.Ldarg_2);
emitter.Generator.Emit(OpCodes.Call, compareMethod);
emitter.Generator.Emit(OpCodes.Ldc_I4_0);
emitter.Generator.Emit(OpCodes.Ceq);
emitter.Generator.Emit(OpCodes.Ret);
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IEqualityComparer<object>).GetMethod(
"Equals",
new Type[]
{
typeof(object),
typeof(object)
}));
}
#endregion
#region GetHashCode
{
MethodEmitter emitter = new MethodEmitter(typeBuilder);
emitter.Define(
/* name */ "GetHashCode",
/* attr */ MethodAttributes.Public | MethodAttributes.Virtual,
/* return */ typeof(int),
/* params */ new Type[] { typeof(object) });
LocalBuilder obj = emitter.CreateLocal(objectType);
emitter.LoadArgument(1);
emitter.CastAs(objectType);
emitter.StoreLocal(obj);
for (int i = 0; i < props.Length; ++i)
{
Property prop = props[i];
emitter.LoadLocal(obj);
emitter.Chain(prop);
Type active = emitter.Active;
MethodInfo getHashCode = active.GetMethod("GetHashCode", Type.EmptyTypes);
if (getHashCode == null)
getHashCode = typeof(object).GetMethod("GetHashCode", Type.EmptyTypes);
if (active != typeof(int))
{
if (!active.IsValueType)
{
LocalBuilder value = emitter.AcquireTemp(active);
Label valueNotNull = emitter.CreateLabel();
Label done = emitter.CreateLabel();
emitter.StoreLocal(value);
emitter.LoadLocal(value);
emitter.BranchIfTrue(valueNotNull);
emitter.Load(0);
emitter.Pop(typeof(int));
emitter.Branch(done);
emitter.MarkLabel(valueNotNull);
emitter.LoadLocal(value);
emitter.Call(getHashCode);
emitter.ReleaseTemp(value);
emitter.MarkLabel(done);
}
else
{
emitter.Call(getHashCode);
}
}
if (i > 0)
emitter.Xor();
}
emitter.Return();
typeBuilder.DefineMethodOverride(
emitter.Method,
typeof(IEqualityComparer<object>).GetMethod(
"GetHashCode",
new Type[]
{
typeof(object)
}));
}
#endregion
#endregion
Type comparerType = typeBuilder.CreateType();
return (IComparer)Activator.CreateInstance(comparerType);
}