fixes one dal dispatching issues (#6547)

Author: michaelgsharp

src/Microsoft.ML.Data/MLContext.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Reflection;
 using Microsoft.ML.Data;
 using Microsoft.ML.Runtime;
 
@@ -171,5 +172,24 @@ private void ProcessMessage(IMessageSource source, ChannelMessage message)
 
         [BestFriend]
         internal void CancelExecution() => ((ICancelable)_env).CancelExecution();
+
+        [BestFriend]
+        internal static readonly bool OneDalDispatchingEnabled = InitializeOneDalDispatchingEnabled();
+
+        private static bool InitializeOneDalDispatchingEnabled()
+        {
+            try
+            {
+                var asm = Assembly.Load("Microsoft.ML.OneDal");
+                var type = asm.GetType("Microsoft.ML.OneDal.OneDalUtils");
+                var method = type.GetMethod("IsDispatchingEnabled", BindingFlags.Public | BindingFlags.Static | BindingFlags.NonPublic);
+                var result = method.Invoke(null, null);
+                return (bool)result;
+            }
+            catch
+            {
+                return false;
+            }
+        }
     }
 }

src/Microsoft.ML.FastTree/RandomForestClassification.cs

@@ -224,7 +224,7 @@ private protected override FastForestBinaryModelParameters TrainModelCore(TrainC
                 FeatureCount = trainData.Schema.Feature.Value.Type.GetValueCount();
                 ConvertData(trainData);
 
-                if (!trainData.Schema.Weight.HasValue && IsDispatchingToOneDalEnabled())
+                if (!trainData.Schema.Weight.HasValue && MLContext.OneDalDispatchingEnabled)
                 {
                     if (FastTreeTrainerOptions.FeatureFraction != 1.0)
                     {
@@ -262,20 +262,6 @@ public static extern unsafe int DecisionForestClassificationCompute(
                 void* lteChildPtr, void* gtChildPtr, void* splitFeaturePtr, void* featureThresholdPtr, void* leafValuesPtr, void* modelPtr);
         }
 
-        [BestFriend]
-        private bool IsDispatchingToOneDalEnabled()
-        {
-            try
-            {
-                return OneDalUtils.IsDispatchingEnabled();
-            }
-            catch (Exception)
-            {
-                // Bail to default implementation upon encountering any situation where dispatch failed
-                return false;
-            }
-        }
-
         [BestFriend]
         private void TrainCoreOneDal(IChannel ch, FloatLabelCursor.Factory cursorFactory, int featureCount)
         {

src/Microsoft.ML.FastTree/RandomForestRegression.cs

@@ -363,7 +363,7 @@ private protected override FastForestRegressionModelParameters TrainModelCore(Tr
                 FeatureCount = trainData.Schema.Feature.Value.Type.GetValueCount();
                 ConvertData(trainData);
 
-                if (!trainData.Schema.Weight.HasValue && IsDispatchingToOneDalEnabled())
+                if (!trainData.Schema.Weight.HasValue && MLContext.OneDalDispatchingEnabled)
                 {
                     if (FastTreeTrainerOptions.FeatureFraction != 1.0)
                     {
@@ -395,20 +395,6 @@ public static extern unsafe int DecisionForestRegressionCompute(
                 void* lteChildPtr, void* gtChildPtr, void* splitFeaturePtr, void* featureThresholdPtr, void* leafValuesPtr, void* modelPtr);
         }
 
-        [BestFriend]
-        private bool IsDispatchingToOneDalEnabled()
-        {
-            try
-            {
-                return OneDalUtils.IsDispatchingEnabled();
-            }
-            catch (Exception)
-            {
-                // fall back to original implementation for any circumstance that prevents dispatching
-                return false;
-            }
-        }
-
         [BestFriend]
         private void TrainCoreOneDal(IChannel ch, FloatLabelCursor.Factory cursorFactory, int featureCount)
         {

src/Microsoft.ML.Mkl.Components/OlsLinearRegression.cs

@@ -406,20 +406,6 @@ private void ComputeMklRegression(IChannel ch, FloatLabelCursor.Factory cursorFa
             xty = null;
         }
 
-        [BestFriend]
-        private bool IsDispatchingToOneDalEnabled()
-        {
-            try
-            {
-                return OneDalUtils.IsDispatchingEnabled();
-            }
-            catch (Exception)
-            {
-                // Bail to default implementation upon any situation that prevents dispatching
-                return false;
-            }
-        }
-
         private OlsModelParameters TrainCore(IChannel ch, FloatLabelCursor.Factory cursorFactory, int featureCount)
         {
             Host.AssertValue(ch);
@@ -440,7 +426,7 @@ private OlsModelParameters TrainCore(IChannel ch, FloatLabelCursor.Factory curso
             var beta = new Double[m];
             Double yMean = 0;
 
-            if (IsDispatchingToOneDalEnabled())
+            if (MLContext.OneDalDispatchingEnabled)
             {
                 ComputeOneDalRegression(ch, cursorFactory, m, ref beta, xtx, ref n, ref yMean);
             }