Changes from code review

Added verification to the benchmark,
put most of output under #if VERBOSE.
Also fixed number of iterations for xunit.perf runs.

1 files changed, 56 insertions, 35 deletions

diff --git a/tests/src/JIT/Performance/CodeQuality/BenchF/Adams/Adams.cs b/tests/src/JIT/Performance/CodeQuality/BenchF/Adams/Adams.cs
index ab4bdc0101..eeb98a6cf2 100644
--- a/tests/src/JIT/Performance/CodeQuality/BenchF/Adams/Adams.cs
+++ b/tests/src/JIT/Performance/CodeQuality/BenchF/Adams/Adams.cs
@@ -11,12 +11,12 @@ using System.Diagnostics;
 #if XUNIT_PERF
 using Xunit;
 using Microsoft.Xunit.Performance;
-#endif
+#endif // XUNIT_PERF
 
 #if XUNIT_PERF
 [assembly: OptimizeForBenchmarks]
 [assembly: MeasureInstructionsRetired]
-#endif
+#endif // XUNIT_PERF
 
 public static class Adams
 {
@@ -24,9 +24,13 @@ public static class Adams
     public static int Iterations = 1;
 #else
     public static int Iterations = 200000;
-#endif
+#endif // DEBUG
 
     static double g_xn, g_yn, g_dn, g_en;
+    const double g_xn_base = 0.09999999E+01;
+    const double g_yn_base = 0.71828180E+00;
+    const double g_dn_base = 0.21287372E-08;
+    const double g_en_base = 0.74505806E-08;
 
     [MethodImpl(MethodImplOptions.NoInlining)]
     private static void Bench()
@@ -35,9 +39,9 @@ public static class Adams
         double xn, yn, dn, en, yxn, h, fnp, ynp, y0, x0, nz;
         int i, k, n, nstep;
 
-#if DEBUG
+#if VERBOSE
         Console.WriteLine(" ADAMS-MOULTON METHOD ");
-#endif // DEBUG 
+#endif // VERBOSE 
 
         n = 4;
         h = 1.0 / 32.0;
@@ -51,9 +55,9 @@ public static class Adams
         nz = 0;
 
         f[1] = x0 + y0;
-#if DEBUG
+#if VERBOSE
         Console.WriteLine("{0},  {1},  {2},  {3},  {4}", nz, x0, y0, dn, en);
-#endif // DEBUG
+#endif // VERBOSE
         xn = x0;
         for (i = 2; i <= 4; i++)
         {
@@ -61,9 +65,9 @@ public static class Adams
             xn = xn + h;
             yn = Soln(xn);
             f[i] = xn + yn;
-#if DEBUG
+#if VERBOSE
             Console.WriteLine("{0},  {1},  {2},  {3},  {4}", k, xn, yn, dn, en);
-#endif // DEBUG 
+#endif // VERBOSE 
         }
 
         for (k = 4; k <= nstep; k++)
@@ -79,16 +83,16 @@ public static class Adams
             f[n] = xn + yn;
             yxn = Soln(xn);
             en = yn - yxn;
-#if DEBUG
+#if VERBOSE
             Console.WriteLine("{0},  {1},  {2},  {3},  {4}", k, xn, yn, dn, en);
-#endif // DEBUG
+#endif // VERBOSE
         }
 
         // Escape calculated values:
-        g_xn += xn;
-        g_yn += yn;
-        g_dn += dn;
-        g_en += en;
+        g_xn = xn;
+        g_yn = yn;
+        g_dn = dn;
+        g_en = en;
     }
 
     private static double Soln(double x)
@@ -96,6 +100,28 @@ public static class Adams
         return (System.Math.Exp(x) - 1.0 - (x));
     }
 
+    [MethodImpl(MethodImplOptions.NoOptimization | MethodImplOptions.NoInlining)]
+    private static bool TestBench()
+    {
+        for (int l = 1; l <= Iterations; l++)
+        {
+            Bench();
+        }
+        
+        bool result = true;
+        // Note: we can't check xn or yn better because of the precision
+        // with which original results are given 
+        result &= System.Math.Abs(g_xn_base - g_xn) <= 1.5e-7;
+        result &= System.Math.Abs(g_yn_base - g_yn) <= 1.5e-7;
+        result &= System.Math.Abs(g_dn) <= 2.5e-9;
+        // Actual error is much bigger than base error;
+        // this is likely due to the fact that the original program was written in Fortran
+        // and was running on a mainframe with a non-IEEE floating point arithmetic
+        // (it's still beyond the published precision of yn)
+        result &= System.Math.Abs(g_en) <= 5.5e-8;
+        return result;
+    }
+
 #if XUNIT_PERF
     [Benchmark]
     public static void Test()
@@ -104,13 +130,12 @@ public static class Adams
         {
             using (iteration.StartMeasurement())
             {
-                Bench();
+                TestBench();
             }
         }
     }
-#endif
+#endif // XUNIT_PERF
 
-    [MethodImpl(MethodImplOptions.NoOptimization)]
     public static int Main(string[] argv)
     {
         if (argv.Length > 0)
@@ -119,25 +144,21 @@ public static class Adams
         }
 
         Stopwatch sw = Stopwatch.StartNew();
-
-        for (int l = 1; l <= Iterations; l++)
-        {
-            Bench();
-        }
+        bool result = TestBench();
         sw.Stop();
 
-        Console.WriteLine("Test iterations: {0}; Total time: {1} sec", Iterations, sw.Elapsed.TotalSeconds);
+        Console.WriteLine(result ? "Passed" : "Failed");
 
-        Console.WriteLine(" BASE.....P1 1/4 (ADAMS-MOULTON), XN = .09999999E +01");
-        Console.WriteLine(" VERIFY...P1 1/4 (ADAMS-MOULTON), XN = {0}\n", g_xn / Iterations);
-        Console.WriteLine(" BASE.....P1 2/4 (ADAMS-MOULTON), YN = .71828180E+00");
-        Console.WriteLine(" VERIFY...P1 2/4 (ADAMS-MOULTON), YN = {0}\n", g_yn / Iterations);
-        Console.WriteLine(" BASE.....P1 3/4 (ADAMS-MOULTON), DN = .21287372E-08");
-        Console.WriteLine(" VERIFY...P1 3/4 (ADAMS-MOULTON), DN = {0}\n", g_dn / Iterations);
-        Console.WriteLine(" BASE.....P1 4/4 (ADAMS-MOULTON), EN = .74505806E-08");
-        Console.WriteLine(" VERIFY...P1 4/4 (ADAMS-MOULTON), EN = {0}", g_en / Iterations);
-
-        Console.WriteLine("Passed");
-        return (100);
+        Console.WriteLine(" BASE.....P1 1/4 (ADAMS-MOULTON), XN = {0}", g_xn_base);
+        Console.WriteLine(" VERIFY...P1 1/4 (ADAMS-MOULTON), XN = {0}\n", g_xn);
+        Console.WriteLine(" BASE.....P1 2/4 (ADAMS-MOULTON), YN = {0}", g_yn_base);
+        Console.WriteLine(" VERIFY...P1 2/4 (ADAMS-MOULTON), YN = {0}\n", g_yn);
+        Console.WriteLine(" BASE.....P1 3/4 (ADAMS-MOULTON), DN = {0}", g_dn_base);
+        Console.WriteLine(" VERIFY...P1 3/4 (ADAMS-MOULTON), DN = {0}\n", g_dn);
+        Console.WriteLine(" BASE.....P1 4/4 (ADAMS-MOULTON), EN = {0}", g_en_base);
+        Console.WriteLine(" VERIFY...P1 4/4 (ADAMS-MOULTON), EN = {0}\n", g_en);
+
+        Console.WriteLine("Test iterations: {0}; Total time: {1} sec", Iterations, sw.Elapsed.TotalSeconds);
+        return (result ? 100 : -1);
     }
 }