Update Enumerable.Min/Max for all IBinaryIntegers (#96605)

The implementations are special-casing most of the built-in ones, in order to delegate to the IBinaryInteger-constrained helper, but it was missing Int128, UInt128, and char. ?hese won't be vectorized, but they'll at least use the more streamlined non-vectorized implementations.
dotnet · Jan 8, 2024 · 0823c5c · 0823c5c
1 parent 8ffc96c
commit 0823c5c
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Showing 4 changed files with 20 additions and 3 deletions.
diff --git a/src/libraries/System.Linq/src/System/Linq/Max.cs b/src/libraries/System.Linq/src/System/Linq/Max.cs
@@ -319,16 +319,20 @@ public static decimal Max(this IEnumerable<decimal> source)
 
             comparer ??= Comparer<TSource>.Default;
 
+            // TODO https://github.com/dotnet/csharplang/discussions/6308: Update this to use generic constraint bridging if/when available.
             if (typeof(TSource) == typeof(byte) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<byte, MaxCalc<byte>>((IEnumerable<byte>)source);
             if (typeof(TSource) == typeof(sbyte) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<sbyte, MaxCalc<sbyte>>((IEnumerable<sbyte>)source);
             if (typeof(TSource) == typeof(ushort) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<ushort, MaxCalc<ushort>>((IEnumerable<ushort>)source);
             if (typeof(TSource) == typeof(short) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<short, MaxCalc<short>>((IEnumerable<short>)source);
+            if (typeof(TSource) == typeof(char) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<char, MaxCalc<char>>((IEnumerable<char>)source);
             if (typeof(TSource) == typeof(uint) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<uint, MaxCalc<uint>>((IEnumerable<uint>)source);
             if (typeof(TSource) == typeof(int) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<int, MaxCalc<int>>((IEnumerable<int>)source);
             if (typeof(TSource) == typeof(ulong) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<ulong, MaxCalc<ulong>>((IEnumerable<ulong>)source);
             if (typeof(TSource) == typeof(long) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<long, MaxCalc<long>>((IEnumerable<long>)source);
             if (typeof(TSource) == typeof(nuint) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<nuint, MaxCalc<nuint>>((IEnumerable<nuint>)source);
             if (typeof(TSource) == typeof(nint) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<nint, MaxCalc<nint>>((IEnumerable<nint>)source);
+            if (typeof(TSource) == typeof(Int128) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<Int128, MaxCalc<Int128>>((IEnumerable<Int128>)source);
+            if (typeof(TSource) == typeof(UInt128) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<UInt128, MaxCalc<UInt128>>((IEnumerable<UInt128>)source);
 
             TSource? value = default;
             using (IEnumerator<TSource> e = source.GetEnumerator())

diff --git a/src/libraries/System.Linq/src/System/Linq/MaxMin.cs b/src/libraries/System.Linq/src/System/Linq/MaxMin.cs
@@ -32,7 +32,7 @@ private static T MinMaxInteger<T, TMinMax>(this IEnumerable<T> source)
                     ThrowHelper.ThrowNoElementsException();
                 }
 
-                if (!Vector128.IsHardwareAccelerated || span.Length < Vector128<T>.Count)
+                if (!Vector128.IsHardwareAccelerated || !Vector128<T>.IsSupported || span.Length < Vector128<T>.Count)
                 {
                     value = span[0];
                     for (int i = 1; i < span.Length; i++)
@@ -43,7 +43,7 @@ private static T MinMaxInteger<T, TMinMax>(this IEnumerable<T> source)
                         }
                     }
                 }
-                else if (!Vector256.IsHardwareAccelerated || span.Length < Vector256<T>.Count)
+                else if (!Vector256.IsHardwareAccelerated || !Vector256<T>.IsSupported || span.Length < Vector256<T>.Count)
                 {
                     ref T current = ref MemoryMarshal.GetReference(span);
                     ref T lastVectorStart = ref Unsafe.Add(ref current, span.Length - Vector128<T>.Count);
@@ -67,7 +67,7 @@ private static T MinMaxInteger<T, TMinMax>(this IEnumerable<T> source)
                         }
                     }
                 }
-                else if (!Vector512.IsHardwareAccelerated || span.Length < Vector512<T>.Count)
+                else if (!Vector512.IsHardwareAccelerated || !Vector512<T>.IsSupported || span.Length < Vector512<T>.Count)
                 {
                     ref T current = ref MemoryMarshal.GetReference(span);
                     ref T lastVectorStart = ref Unsafe.Add(ref current, span.Length - Vector256<T>.Count);

diff --git a/src/libraries/System.Linq/src/System/Linq/Min.cs b/src/libraries/System.Linq/src/System/Linq/Min.cs
@@ -297,16 +297,20 @@ public static decimal Min(this IEnumerable<decimal> source)
 
             comparer ??= Comparer<TSource>.Default;
 
+            // TODO https://github.com/dotnet/csharplang/discussions/6308: Update this to use generic constraint bridging if/when available.
             if (typeof(TSource) == typeof(byte) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<byte, MinCalc<byte>>((IEnumerable<byte>)source);
             if (typeof(TSource) == typeof(sbyte) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<sbyte, MinCalc<sbyte>>((IEnumerable<sbyte>)source);
             if (typeof(TSource) == typeof(ushort) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<ushort, MinCalc<ushort>>((IEnumerable<ushort>)source);
             if (typeof(TSource) == typeof(short) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<short, MinCalc<short>>((IEnumerable<short>)source);
+            if (typeof(TSource) == typeof(char) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<char, MinCalc<char>>((IEnumerable<char>)source);
             if (typeof(TSource) == typeof(uint) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<uint, MinCalc<uint>>((IEnumerable<uint>)source);
             if (typeof(TSource) == typeof(int) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<int, MinCalc<int>>((IEnumerable<int>)source);
             if (typeof(TSource) == typeof(ulong) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<ulong, MinCalc<ulong>>((IEnumerable<ulong>)source);
             if (typeof(TSource) == typeof(long) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<long, MinCalc<long>>((IEnumerable<long>)source);
             if (typeof(TSource) == typeof(nuint) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<nuint, MinCalc<nuint>>((IEnumerable<nuint>)source);
             if (typeof(TSource) == typeof(nint) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<nint, MinCalc<nint>>((IEnumerable<nint>)source);
+            if (typeof(TSource) == typeof(Int128) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<Int128, MinCalc<Int128>>((IEnumerable<Int128>)source);
+            if (typeof(TSource) == typeof(UInt128) && comparer == Comparer<TSource>.Default) return (TSource)(object)MinMaxInteger<UInt128, MinCalc<UInt128>>((IEnumerable<UInt128>)source);
 
             TSource? value = default;
             using (IEnumerator<TSource> e = source.GetEnumerator())

diff --git a/src/libraries/System.Linq/tests/MaxTests.cs b/src/libraries/System.Linq/tests/MaxTests.cs
@@ -28,6 +28,9 @@ public static IEnumerable<object[]> Max_AllTypes_TestData()
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (short)i)), (short)(length + length - 1) };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (short)i).ToArray()), (short)(length + length - 1) };
 
+                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (char)i)), (char)(length + length - 1) };
+                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (char)i).ToArray()), (char)(length + length - 1) };
+
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (uint)i)), (uint)(length + length - 1) };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (uint)i).ToArray()), (uint)(length + length - 1) };
 
@@ -54,6 +57,12 @@ public static IEnumerable<object[]> Max_AllTypes_TestData()
 
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (nint)i)), (nint)(length + length - 1) };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (nint)i).ToArray()), (nint)(length + length - 1) };
+
+                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (Int128)i)), (Int128)(length + length - 1) };
+                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (Int128)i).ToArray()), (Int128)(length + length - 1) };
+
+                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (UInt128)i)), (UInt128)(length + length - 1) };
+                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (UInt128)i).ToArray()), (UInt128)(length + length - 1) };
             }
         }