[System.Security.SecuritySafeCritical] // auto-generated
private static Comparer <T> CreateComparer()
{
RuntimeType t = (RuntimeType)typeof(T);
// If T implements IComparable<T> return a GenericComparer<T>
#if FEATURE_LEGACYNETCF
// Pre-Apollo Windows Phone call the overload that sorts the keys, not values this achieves the same result
if (CompatibilitySwitches.IsAppEarlierThanWindowsPhone8)
{
if (t.ImplementInterface(typeof(IComparable <T>)))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), t));
}
}
else
#endif
if (typeof(IComparable <T>).IsAssignableFrom(t))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), t));
}
// If T is a Nullable<U> where U implements IComparable<U> return a NullableComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType(u).IsAssignableFrom(u))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), u));
}
}
// Otherwise return an ObjectComparer<T>
return(new ObjectComparer <T>());
}
private static EqualityComparer <T> CreateComparer()
{
RuntimeType c = (RuntimeType)typeof(T);
if (c == typeof(byte))
{
return((EqualityComparer <T>) new ByteEqualityComparer());
}
if (typeof(IEquatable <T>).IsAssignableFrom(c))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericEqualityComparer <int>), c));
}
if (c.IsGenericType && (c.GetGenericTypeDefinition() == typeof(Nullable <>)))
{
RuntimeType type2 = (RuntimeType)c.GetGenericArguments()[0];
if (typeof(IEquatable <>).MakeGenericType(new Type[] { type2 }).IsAssignableFrom(type2))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableEqualityComparer <int>), type2));
}
}
if (c.IsEnum && (Enum.GetUnderlyingType(c) == typeof(int)))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), c));
}
return(new ObjectEqualityComparer <T>());
}
/// <summary>
/// Creates the default <see cref="EqualityComparer{T}"/> for an enum type.
/// </summary>
/// <param name="enumType">The enum type to create the default equality comparer for.</param>
private static object?TryCreateEnumEqualityComparer(RuntimeType enumType)
{
Debug.Assert(enumType != null);
Debug.Assert(enumType.IsEnum);
// See the METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST and METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST_LONG cases in getILIntrinsicImplementation
// for how we cast the enum types to integral values in the comparer without boxing.
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(enumType));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing.
switch (underlyingTypeCode)
{
case TypeCode.Int32:
case TypeCode.UInt32:
case TypeCode.SByte:
case TypeCode.Byte:
case TypeCode.Int16:
case TypeCode.Int64:
case TypeCode.UInt64:
case TypeCode.UInt16:
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <>), enumType));
}
return(null);
}
//
// Note that logic in this method is replicated in vm\compile.cpp to ensure that NGen
// saves the right instantiations
//
private static Comparer <T> CreateComparer()
{
object result = null;
RuntimeType t = (RuntimeType)typeof(T);
// If T implements IComparable<T> return a GenericComparer<T>
if (typeof(IComparable <T>).IsAssignableFrom(t))
{
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), t);
}
else if (default(T) == null)
{
// If T is a Nullable<U> where U implements IComparable<U> return a NullableComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType(u).IsAssignableFrom(u))
{
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), u);
}
}
}
else if (t.IsEnum)
{
// Explicitly call Enum.GetUnderlyingType here. Although GetTypeCode
// ends up doing this anyway, we end up avoiding an unnecessary P/Invoke
// and virtual method call.
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(t));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing
// Specialize differently for signed/unsigned types so we avoid problems with large numbers
switch (underlyingTypeCode)
{
case TypeCode.SByte:
case TypeCode.Int16:
case TypeCode.Int32:
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(Int32EnumComparer <int>), t);
break;
case TypeCode.Byte:
case TypeCode.UInt16:
case TypeCode.UInt32:
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(UInt32EnumComparer <uint>), t);
break;
// 64-bit enums: use UnsafeEnumCastLong
case TypeCode.Int64:
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(Int64EnumComparer <long>), t);
break;
case TypeCode.UInt64:
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(UInt64EnumComparer <ulong>), t);
break;
}
}
return(result != null ?
(Comparer <T>)result :
new ObjectComparer <T>()); // Fallback to ObjectComparer, which uses boxing
}
[System.Security.SecuritySafeCritical] // auto-generated
private static EqualityComparer <T> CreateComparer()
{
Contract.Ensures(Contract.Result <EqualityComparer <T> >() != null);
RuntimeType t = (RuntimeType)typeof(T);
// Specialize type byte for performance reasons
if (t == typeof(byte))
{
return((EqualityComparer <T>)(object)(new ByteEqualityComparer()));
}
// If T implements IEquatable<T> return a GenericEqualityComparer<T>
if (typeof(IEquatable <T>).IsAssignableFrom(t))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericEqualityComparer <int>), t));
}
// If T is a Nullable<U> where U implements IEquatable<U> return a NullableEqualityComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IEquatable <>).MakeGenericType(u).IsAssignableFrom(u))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableEqualityComparer <int>), u));
}
}
// If T is an int-based Enum, return an EnumEqualityComparer<T>
// See the METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST and METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST_LONG cases in getILIntrinsicImplementation
if (t.IsEnum && Enum.GetUnderlyingType(t) == typeof(int))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), t));
}
// Otherwise return an ObjectEqualityComparer<T>
return(new ObjectEqualityComparer <T>());
}
[System.Security.SecuritySafeCritical] // auto-generated
private static Comparer <T> CreateComparer()
{
object result = null;
RuntimeType t = (RuntimeType)typeof(T);
// If T implements IComparable<T> return a GenericComparer<T>
if (typeof(IComparable <T>).IsAssignableFrom(t))
{
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), t);
}
else if (default(T) == null)
{
// If T is a Nullable<U> where U implements IComparable<U> return a NullableComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType(u).IsAssignableFrom(u))
{
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), u);
}
}
}
return(result != null ?
(Comparer <T>)result :
new ObjectComparer <T>()); // Fallback to ObjectComparer, which uses boxing
}
/// <summary>
/// Creates the default <see cref="Comparer{T}"/>.
/// </summary>
/// <param name="type">The type to create the default comparer for.</param>
/// <remarks>
/// The logic in this method is replicated in vm/compile.cpp to ensure that NGen saves the right instantiations,
/// and in vm/jitinterface.cpp so the jit can model the behavior of this method.
/// </remarks>
internal static object CreateDefaultComparer(Type type)
{
Debug.Assert(type != null && type is RuntimeType);
object?result = null;
var runtimeType = (RuntimeType)type;
// If T implements IComparable<T> return a GenericComparer<T>
if (typeof(IComparable <>).MakeGenericType(type).IsAssignableFrom(type))
{
result = CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), runtimeType);
}
else if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(Nullable <>))
{
// Nullable does not implement IComparable<T?> directly because that would add an extra interface call per comparison.
var embeddedType = (RuntimeType)type.GetGenericArguments()[0];
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), embeddedType);
}
// The comparer for enums is specialized to avoid boxing.
else if (type.IsEnum)
{
result = TryCreateEnumComparer(runtimeType);
}
return(result ?? CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(ObjectComparer <object>), runtimeType));
}
/// <summary>
/// Creates the default <see cref="EqualityComparer{T}"/> for an enum type.
/// </summary>
/// <param name="enumType">The enum type to create the default equality comparer for.</param>
private static object TryCreateEnumEqualityComparer(RuntimeType enumType)
{
Debug.Assert(enumType != null);
Debug.Assert(enumType.IsEnum);
// See the METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST and METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST_LONG cases in getILIntrinsicImplementation
// for how we cast the enum types to integral values in the comparer without boxing.
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(enumType));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing.
// Note: We have different comparers for short and sbyte, since for those types GetHashCode does not simply return the value.
// We need to preserve what they would return.
switch (underlyingTypeCode)
{
case TypeCode.Int16:
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(ShortEnumEqualityComparer <short>), enumType));
case TypeCode.SByte:
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(SByteEnumEqualityComparer <sbyte>), enumType));
case TypeCode.Int32:
case TypeCode.UInt32:
case TypeCode.Byte:
case TypeCode.UInt16:
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), enumType));
case TypeCode.Int64:
case TypeCode.UInt64:
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(LongEnumEqualityComparer <long>), enumType));
}
return(null);
}
/// <summary>
/// Creates the default <see cref="Comparer{T}"/> for an enum type.
/// </summary>
/// <param name="enumType">The enum type to create the default comparer for.</param>
private static object?TryCreateEnumComparer(RuntimeType enumType)
{
Debug.Assert(enumType != null);
Debug.Assert(enumType.IsEnum);
// Explicitly call Enum.GetUnderlyingType here. Although GetTypeCode
// ends up doing this anyway, we end up avoiding an unnecessary P/Invoke
// and virtual method call.
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(enumType));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing.
// Specialize differently for signed/unsigned types so we avoid problems with large numbers.
switch (underlyingTypeCode)
{
case TypeCode.SByte:
case TypeCode.Int16:
case TypeCode.Int32:
case TypeCode.Byte:
case TypeCode.UInt16:
case TypeCode.UInt32:
case TypeCode.Int64:
case TypeCode.UInt64:
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumComparer <>), enumType));
}
return(null);
}
[System.Security.SecuritySafeCritical] // auto-generated
private static EqualityComparer <T> CreateComparer()
{
Contract.Ensures(Contract.Result <EqualityComparer <T> >() != null);
RuntimeType t = (RuntimeType)typeof(T);//获取泛型格式
// 用于性能原因的专门类型字节
if (t == typeof(byte))
{
return((EqualityComparer <T>)(object)(new ByteEqualityComparer()));
}
// If T implements IEquatable<T> return a GenericEqualityComparer<T>
// 如果T实现IEquatable<T>,则返回GenericEqualityComparer<T>
if (typeof(IEquatable <T>).IsAssignableFrom(t))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericEqualityComparer <int>), t));
}
// If T is a Nullable<U> where U implements IEquatable<U> return a NullableEqualityComparer<U>
// 如果T是一个实现了IEquatable<U>的Nullable<U>，将返回一个NullableEqualityComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IEquatable <>).MakeGenericType(u).IsAssignableFrom(u))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableEqualityComparer <int>), u));
}
}
// See the METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST and METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST_LONG cases in getILIntrinsicImplementation
if (t.IsEnum)
{
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(t));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing
// Note: We have different comparers for Short and SByte because for those types we need to make sure we call GetHashCode on the actual underlying type as the
// implementation of GetHashCode is more complex than for the other types.
switch (underlyingTypeCode)
{
case TypeCode.Int16: // short
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(ShortEnumEqualityComparer <short>), t));
case TypeCode.SByte:
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(SByteEnumEqualityComparer <sbyte>), t));
case TypeCode.Int32:
case TypeCode.UInt32:
case TypeCode.Byte:
case TypeCode.UInt16: //ushort
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), t));
case TypeCode.Int64:
case TypeCode.UInt64:
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(LongEnumEqualityComparer <long>), t));
}
}
// Otherwise return an ObjectEqualityComparer<T>
return(new ObjectEqualityComparer <T>());
}
private static IArraySortHelper <T> CreateArraySortHelper()
{
IArraySortHelper <T> defaultArraySortHelper;
if (typeof(IComparable <T>).IsAssignableFrom(typeof(T)))
{
defaultArraySortHelper = (IArraySortHelper <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericArraySortHelper <string>), (RuntimeType)typeof(T));
}
else
{
defaultArraySortHelper = new ArraySortHelper <T>();
}
return(defaultArraySortHelper);
}
/// <summary>
/// Creates the default <see cref="Comparer{T}"/> for a nullable type.
/// </summary>
/// <param name="nullableType">The nullable type to create the default comparer for.</param>
private static object TryCreateNullableComparer(RuntimeType nullableType)
{
Debug.Assert(nullableType != null);
Debug.Assert(nullableType.IsGenericType && nullableType.GetGenericTypeDefinition() == typeof(Nullable <>));
var embeddedType = (RuntimeType)nullableType.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType(embeddedType).IsAssignableFrom(embeddedType))
{
return(RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), embeddedType));
}
return(null);
}
private static EqualityComparer <T> CreateComparer()
{
RuntimeType runtimeType = (RuntimeType)typeof(T);
if (runtimeType == typeof(byte))
{
return((EqualityComparer <T>) new ByteEqualityComparer());
}
if (typeof(IEquatable <T>).IsAssignableFrom(runtimeType))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericEqualityComparer <int>), runtimeType));
}
if (runtimeType.IsGenericType && runtimeType.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType runtimeType2 = (RuntimeType)runtimeType.GetGenericArguments()[0];
if (typeof(IEquatable <>).MakeGenericType(new Type[]
{
runtimeType2
}).IsAssignableFrom(runtimeType2))
{
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableEqualityComparer <int>), runtimeType2));
}
}
if (runtimeType.IsEnum)
{
switch (Type.GetTypeCode(Enum.GetUnderlyingType(runtimeType)))
{
case TypeCode.SByte:
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(SByteEnumEqualityComparer <sbyte>), runtimeType));
case TypeCode.Byte:
case TypeCode.UInt16:
case TypeCode.Int32:
case TypeCode.UInt32:
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), runtimeType));
case TypeCode.Int16:
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(ShortEnumEqualityComparer <short>), runtimeType));
case TypeCode.Int64:
case TypeCode.UInt64:
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(LongEnumEqualityComparer <long>), runtimeType));
}
}
return(new ObjectEqualityComparer <T>());
}
private static Comparer <T> CreateComparer()
{
RuntimeType c = (RuntimeType)typeof(T);
if (typeof(IComparable <T>).IsAssignableFrom(c))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), c));
}
if (c.IsGenericType && (c.GetGenericTypeDefinition() == typeof(Nullable <>)))
{
RuntimeType type2 = (RuntimeType)c.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType(new Type[] { type2 }).IsAssignableFrom(type2))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), type2));
}
}
return(new ObjectComparer <T>());
}
private static Comparer <T> CreateComparer()
{
RuntimeType genericParameter1 = (RuntimeType)typeof(T);
if (typeof(IComparable <T>).IsAssignableFrom((Type)genericParameter1))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), genericParameter1));
}
if (genericParameter1.IsGenericType && genericParameter1.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType genericParameter2 = (RuntimeType)genericParameter1.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType((Type)genericParameter2).IsAssignableFrom((Type)genericParameter2))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), genericParameter2));
}
}
return((Comparer <T>) new ObjectComparer <T>());
}
[System.Security.SecuritySafeCritical] // auto-generated
private static Comparer <T> CreateComparer()
{
RuntimeType t = (RuntimeType)typeof(T);
// If T implements IComparable<T> return a GenericComparer<T>
if (typeof(IComparable <T>).IsAssignableFrom(t))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericComparer <int>), t));
}
// If T is a Nullable<U> where U implements IComparable<U> return a NullableComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IComparable <>).MakeGenericType(u).IsAssignableFrom(u))
{
return((Comparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableComparer <int>), u));
}
}
// Otherwise return an ObjectComparer<T>
return(new ObjectComparer <T>());
}
[System.Security.SecuritySafeCritical] // auto-generated
private static EqualityComparer <T> CreateComparer()
{
Contract.Ensures(Contract.Result <EqualityComparer <T> >() != null);
object result = null;
RuntimeType t = (RuntimeType)typeof(T);
// Specialize type byte for performance reasons
if (t == typeof(byte))
{
result = new ByteEqualityComparer();
}
// If T implements IEquatable<T> return a GenericEqualityComparer<T>
else if (typeof(IEquatable <T>).IsAssignableFrom(t))
{
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericEqualityComparer <int>), t);
}
else if (default(T) == null) // Reference type/Nullable
{
// If T is a Nullable<U> where U implements IEquatable<U> return a NullableEqualityComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IEquatable <>).MakeGenericType(u).IsAssignableFrom(u))
{
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableEqualityComparer <int>), u);
}
}
}
// See the METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST and METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST_LONG cases in getILIntrinsicImplementation
else if (t.IsEnum)
{
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(t));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing
// Note: We have different comparers for Short and SByte because for those types we need to make sure we call GetHashCode on the actual underlying type as the
// implementation of GetHashCode is more complex than for the other types.
switch (underlyingTypeCode)
{
case TypeCode.Int16: // short
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(ShortEnumEqualityComparer <short>), t);
break;
case TypeCode.SByte:
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(SByteEnumEqualityComparer <sbyte>), t);
break;
case TypeCode.Int32:
case TypeCode.UInt32:
case TypeCode.Byte:
case TypeCode.UInt16: //ushort
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), t);
break;
case TypeCode.Int64:
case TypeCode.UInt64:
result = RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(LongEnumEqualityComparer <long>), t);
break;
}
}
return(result != null ?
(EqualityComparer <T>)result :
new ObjectEqualityComparer <T>()); // Fallback to ObjectEqualityComparer, which uses boxing
}
[System.Security.SecuritySafeCritical] // auto-generated
private static EqualityComparer <T> CreateComparer()
{
Contract.Ensures(Contract.Result <EqualityComparer <T> >() != null);
RuntimeType t = (RuntimeType)typeof(T);
// Specialize type byte for performance reasons
if (t == typeof(byte))
{
return((EqualityComparer <T>)(object)(new ByteEqualityComparer()));
}
/////////////////////////////////////////////////
// KEEP THIS IN SYNC WITH THE DEVIRT CODE
// IN METHOD-TO-IR.C
/////////////////////////////////////////////////
#if MOBILE
// Breaks .net serialization compatibility
if (t == typeof(string))
{
return((EqualityComparer <T>)(object) new InternalStringComparer());
}
#endif
// If T implements IEquatable<T> return a GenericEqualityComparer<T>
if (typeof(IEquatable <T>).IsAssignableFrom(t))
{
#if MONO
return((EqualityComparer <T>)RuntimeType.CreateInstanceForAnotherGenericParameter(typeof(GenericEqualityComparer <>), t));
#else
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(GenericEqualityComparer <int>), t));
#endif
}
// If T is a Nullable<U> where U implements IEquatable<U> return a NullableEqualityComparer<U>
if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable <>))
{
RuntimeType u = (RuntimeType)t.GetGenericArguments()[0];
if (typeof(IEquatable <>).MakeGenericType(u).IsAssignableFrom(u))
{
#if MONO
return((EqualityComparer <T>)RuntimeType.CreateInstanceForAnotherGenericParameter(typeof(NullableEqualityComparer <>), u));
#else
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(NullableEqualityComparer <int>), u));
#endif
}
}
// See the METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST and METHOD__JIT_HELPERS__UNSAFE_ENUM_CAST_LONG cases in getILIntrinsicImplementation
if (t.IsEnum)
{
TypeCode underlyingTypeCode = Type.GetTypeCode(Enum.GetUnderlyingType(t));
// Depending on the enum type, we need to special case the comparers so that we avoid boxing
// Note: We have different comparers for Short and SByte because for those types we need to make sure we call GetHashCode on the actual underlying type as the
// implementation of GetHashCode is more complex than for the other types.
switch (underlyingTypeCode)
{
case TypeCode.Int16: // short
#if MONO
return((EqualityComparer <T>)RuntimeType.CreateInstanceForAnotherGenericParameter(typeof(ShortEnumEqualityComparer <>), t));
#else
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(ShortEnumEqualityComparer <short>), t));
#endif
case TypeCode.SByte:
#if MONO
return((EqualityComparer <T>)RuntimeType.CreateInstanceForAnotherGenericParameter(typeof(SByteEnumEqualityComparer <>), t));
#else
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(SByteEnumEqualityComparer <sbyte>), t));
#endif
case TypeCode.Int32:
case TypeCode.UInt32:
case TypeCode.Byte:
case TypeCode.UInt16: //ushort
#if MONO
return((EqualityComparer <T>)RuntimeType.CreateInstanceForAnotherGenericParameter(typeof(EnumEqualityComparer <>), t));
#else
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(EnumEqualityComparer <int>), t));
#endif
case TypeCode.Int64:
case TypeCode.UInt64:
#if MONO
return((EqualityComparer <T>)RuntimeType.CreateInstanceForAnotherGenericParameter(typeof(LongEnumEqualityComparer <>), t));
#else
return((EqualityComparer <T>)RuntimeTypeHandle.CreateInstanceForAnotherGenericParameter((RuntimeType)typeof(LongEnumEqualityComparer <long>), t));
#endif
}
}
// Otherwise return an ObjectEqualityComparer<T>
return(new ObjectEqualityComparer <T>());
}
