Vector512 Support for Enumerable<int>.Min/Max (#93369)

* Vector512 Support for Enumerable<int>.Min/Max * implement comparer in Min/Max * remove trailing whitespace * remove conditions to only target NET 8 as Linq Packages is versioned anyway * minor codestyle fix * increate Max_AllTypes_TestData to be at least one elemend wider than Vector512 * avoid generating testdata for sbyte which are outside the representable range * dont overflow the datatype inside the unittest * dont generate testdata which leads to overflows in the number type during test
dotnet · Oct 16, 2023 · cccdc1d · cccdc1d
1 parent 3eae196
commit cccdc1d
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Showing 5 changed files with 40 additions and 7 deletions.
diff --git a/src/libraries/System.Linq/src/System/Linq/Max.cs b/src/libraries/System.Linq/src/System/Linq/Max.cs
@@ -18,6 +18,7 @@ public static partial class Enumerable
             public static bool Compare(T left, T right) => left > right;
             public static Vector128<T> Compare(Vector128<T> left, Vector128<T> right) => Vector128.Max(left, right);
             public static Vector256<T> Compare(Vector256<T> left, Vector256<T> right) => Vector256.Max(left, right);
+            public static Vector512<T> Compare(Vector512<T> left, Vector512<T> right) => Vector512.Max(left, right);
         }
 
         public static int? Max(this IEnumerable<int?> source) => MaxInteger(source);

diff --git a/src/libraries/System.Linq/src/System/Linq/MaxMin.cs b/src/libraries/System.Linq/src/System/Linq/MaxMin.cs
@@ -16,6 +16,7 @@ private interface IMinMaxCalc<T> where T : struct, IBinaryInteger<T>
             public static abstract bool Compare(T left, T right);
             public static abstract Vector128<T> Compare(Vector128<T> left, Vector128<T> right);
             public static abstract Vector256<T> Compare(Vector256<T> left, Vector256<T> right);
+            public static abstract Vector512<T> Compare(Vector512<T> left, Vector512<T> right);
         }
 
         private static T MinMaxInteger<T, TMinMax>(this IEnumerable<T> source)
@@ -66,7 +67,7 @@ private static T MinMaxInteger<T, TMinMax>(this IEnumerable<T> source)
                         }
                     }
                 }
-                else
+                else if (!Vector512.IsHardwareAccelerated || 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);
@@ -90,6 +91,30 @@ private static T MinMaxInteger<T, TMinMax>(this IEnumerable<T> source)
                         }
                     }
                 }
+                else
+                {
+                    ref T current = ref MemoryMarshal.GetReference(span);
+                    ref T lastVectorStart = ref Unsafe.Add(ref current, span.Length - Vector512<T>.Count);
+
+                    Vector512<T> best = Vector512.LoadUnsafe(ref current);
+                    current = ref Unsafe.Add(ref current, Vector512<T>.Count);
+
+                    while (Unsafe.IsAddressLessThan(ref current, ref lastVectorStart))
+                    {
+                        best = TMinMax.Compare(best, Vector512.LoadUnsafe(ref current));
+                        current = ref Unsafe.Add(ref current, Vector512<T>.Count);
+                    }
+                    best = TMinMax.Compare(best, Vector512.LoadUnsafe(ref lastVectorStart));
+
+                    value = best[0];
+                    for (int i = 1; i < Vector512<T>.Count; i++)
+                    {
+                        if (TMinMax.Compare(best[i], value))
+                        {
+                            value = best[i];
+                        }
+                    }
+                }
             }
             else
             {

diff --git a/src/libraries/System.Linq/src/System/Linq/Min.cs b/src/libraries/System.Linq/src/System/Linq/Min.cs
@@ -18,6 +18,7 @@ public static partial class Enumerable
             public static bool Compare(T left, T right) => left < right;
             public static Vector128<T> Compare(Vector128<T> left, Vector128<T> right) => Vector128.Min(left, right);
             public static Vector256<T> Compare(Vector256<T> left, Vector256<T> right) => Vector256.Min(left, right);
+            public static Vector512<T> Compare(Vector512<T> left, Vector512<T> right) => Vector512.Min(left, right);
         }
 
         public static int? Min(this IEnumerable<int?> source) => MinInteger(source);

diff --git a/src/libraries/System.Linq/tests/MaxTests.cs b/src/libraries/System.Linq/tests/MaxTests.cs
@@ -11,13 +11,16 @@ public class MaxTests : EnumerableTests
     {
         public static IEnumerable<object[]> Max_AllTypes_TestData()
         {
-            for (int length = 2; length < 33; length++)
+            for (int length = 2; length < 65; length++)
             {
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (byte)i)), (byte)(length + length - 1) };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (byte)i).ToArray()), (byte)(length + length - 1) };
 
-                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i)), (sbyte)(length + length - 1) };
-                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i).ToArray()), (sbyte)(length + length - 1) };
+                // Unit Tests does +T.One so we should generate data up to one value below sbyte.MaxValue
+                if ((length + length) < sbyte.MaxValue) {
+                    yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i)), (sbyte)(length + length - 1) };
+                    yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i).ToArray()), (sbyte)(length + length - 1) };
+                }
 
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (ushort)i)), (ushort)(length + length - 1) };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (ushort)i).ToArray()), (ushort)(length + length - 1) };

diff --git a/src/libraries/System.Linq/tests/MinTests.cs b/src/libraries/System.Linq/tests/MinTests.cs
@@ -11,13 +11,16 @@ public class MinTests : EnumerableTests
     {
         public static IEnumerable<object[]> Min_AllTypes_TestData()
         {
-            for (int length = 2; length < 33; length++)
+            for (int length = 2; length < 65; length++)
             {
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (byte)i)), (byte)length };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (byte)i).ToArray()), (byte)length };
 
-                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i)), (sbyte)length };
-                yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i).ToArray()), (sbyte)length };
+                // Unit Tests does +T.One so we should generate data up to one value below sbyte.MaxValue, otherwise the type overflows
+                if ((length + length) < sbyte.MaxValue) {
+                    yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i)), (sbyte)length };
+                    yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (sbyte)i).ToArray()), (sbyte)length };
+                }
 
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (ushort)i)), (ushort)length };
                 yield return new object[] { Shuffler.Shuffle(Enumerable.Range(length, length).Select(i => (ushort)i).ToArray()), (ushort)length };