Imported Upstream version 1.1.0upstream/1.1.0

1 files changed, 116 insertions, 0 deletions

diff --git a/tests/src/JIT/Performance/CodeQuality/BenchI/Permutate/Permutate.cs b/tests/src/JIT/Performance/CodeQuality/BenchI/Permutate/Permutate.cs
new file mode 100644
index 0000000000..d7457cdbc1
--- /dev/null
+++ b/tests/src/JIT/Performance/CodeQuality/BenchI/Permutate/Permutate.cs
@@ -0,0 +1,116 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+//
+
+using Microsoft.Xunit.Performance;
+using System;
+using System.Runtime.CompilerServices;
+using Xunit;
+
+[assembly: OptimizeForBenchmarks]
+[assembly: MeasureInstructionsRetired]
+
+public class Permutate
+{
+#if DEBUG
+    public const int Iterations = 1;
+#else
+    public const int Iterations = 20000;
+#endif
+
+    private int[] _permArray = new int[11];
+    private static int s_pctr;
+
+    private static
+    void Swap(int[] arr, int i, int j)
+    {
+        int t = arr[i];
+        arr[i] = arr[j];
+        arr[j] = t;
+    }
+
+    private void Initialize()
+    {
+        for (int i = 1; i <= 7; i++)
+        {
+            _permArray[i] = i - 1;
+        }
+    }
+
+    private void PermuteArray(int n)
+    {
+        int k;
+        s_pctr = s_pctr + 1;
+        if (n != 1)
+        {
+            PermuteArray(n - 1);
+            for (k = n - 1; k >= 1; k--)
+            {
+                Swap(_permArray, n, k);
+                PermuteArray(n - 1);
+                Swap(_permArray, n, k);
+            }
+        }
+    }
+
+    private bool Validate()
+    {
+        int k = 0;
+
+        for (int i = 0; i <= 6; i++)
+        {
+            for (int j = 1; j <= 7; j++)
+            {
+                if (_permArray[j] == i)
+                {
+                    k = k + 1;
+                }
+            }
+        }
+
+        return (k == 7);
+    }
+
+    [MethodImpl(MethodImplOptions.NoInlining)]
+    private bool Bench()
+    {
+        Initialize();
+
+        for (int i = 0; i < Iterations; ++i)
+        {
+            s_pctr = 0;
+            PermuteArray(7);
+        }
+
+        bool result = Validate();
+
+        return result;
+    }
+
+    [Benchmark]
+    public static void Test()
+    {
+        Permutate P = new Permutate();
+        foreach (var iteration in Benchmark.Iterations)
+        {
+            using (iteration.StartMeasurement())
+            {
+                P.Bench();
+            }
+        }
+    }
+
+    private static bool TestBase()
+    {
+        Permutate P = new Permutate();
+        bool result = P.Bench();
+        return result;
+    }
+
+    public static int Main()
+    {
+        bool result = TestBase();
+        return (result ? 100 : -1);
+    }
+}