Avoid boxing and unnecessary array allocations (#12175)

There are several delegates called during build that cause some sneaky
allocations. For instance, there is boxing of the `BuildRequestEngineStatus` enum.

The culprit is the `ErrorUtilities.VerifyThrow()` calls that take
`object` as parameters for the formatted message. To make the call, the
enum gets boxed even when the condition check returns `true`. Adding
additional overloads that take the specific type lets multiple callers
benefit, and I did some additional cleanup in the delegates to remove
some allocations.

Author: Erarndt

src/Build/BackEnd/Components/BuildRequestEngine/BuildRequestEngine.cs

@@ -343,7 +343,7 @@ public void SubmitBuildRequest(BuildRequest request)
             QueueAction(
                 () =>
                 {
-                    ErrorUtilities.VerifyThrow(_status != BuildRequestEngineStatus.Shutdown && _status != BuildRequestEngineStatus.Uninitialized, "Engine loop not yet started, status is {0}.", _status);
+                    ErrorUtilities.VerifyThrow(_status != BuildRequestEngineStatus.Shutdown && _status != BuildRequestEngineStatus.Uninitialized, "Engine loop not yet started, status is {0}.", _status.Box());
                     TraceEngine("Request {0}({1}) (nr {2}) received and activated.", request.GlobalRequestId, request.ConfigurationId, request.NodeRequestId);
 
                     ErrorUtilities.VerifyThrow(!_requestsByGlobalRequestId.ContainsKey(request.GlobalRequestId), "Request {0} is already known to the engine.", request.GlobalRequestId);
@@ -363,7 +363,7 @@ public void SubmitBuildRequest(BuildRequest request)
                         config.RetrieveFromCache();
                         ((IBuildResults)resultToReport).SavedCurrentDirectory = config.SavedCurrentDirectory;
                         ((IBuildResults)resultToReport).SavedEnvironmentVariables = config.SavedEnvironmentVariables;
-                        if (!request.BuildRequestDataFlags.HasFlag(BuildRequestDataFlags.IgnoreExistingProjectState))
+                        if ((request.BuildRequestDataFlags & BuildRequestDataFlags.IgnoreExistingProjectState) != BuildRequestDataFlags.IgnoreExistingProjectState)
                         {
                             resultToReport.ProjectStateAfterBuild = config.Project;
                         }
@@ -414,7 +414,7 @@ public void UnblockBuildRequest(BuildRequestUnblocker unblocker)
             QueueAction(
                 () =>
                 {
-                    ErrorUtilities.VerifyThrow(_status != BuildRequestEngineStatus.Shutdown && _status != BuildRequestEngineStatus.Uninitialized, "Engine loop not yet started, status is {0}.", _status);
+                    ErrorUtilities.VerifyThrow(_status != BuildRequestEngineStatus.Shutdown && _status != BuildRequestEngineStatus.Uninitialized, "Engine loop not yet started, status is {0}.", _status.Box());
                     ErrorUtilities.VerifyThrow(_requestsByGlobalRequestId.ContainsKey(unblocker.BlockedRequestId), "Request {0} is not known to the engine.", unblocker.BlockedRequestId);
                     BuildRequestEntry entry = _requestsByGlobalRequestId[unblocker.BlockedRequestId];
 
@@ -467,7 +467,11 @@ public void UnblockBuildRequest(BuildRequestUnblocker unblocker)
                         }
                         else
                         {
-                            TraceEngine("Request {0}({1}) (nr {2}) is no longer waiting on nr {3} (UBR).  Results are {4}.", entry.Request.GlobalRequestId, entry.Request.ConfigurationId, entry.Request.NodeRequestId, result.NodeRequestId, result.OverallResult);
+                            // PERF: Explicitly check the debug flag here so that we don't pay the cost for getting OverallResult
+                            if (_debugDumpState)
+                            {
+                                TraceEngine("Request {0}({1}) (nr {2}) is no longer waiting on nr {3} (UBR).  Results are {4}.", entry.Request.GlobalRequestId, entry.Request.ConfigurationId, entry.Request.NodeRequestId, result.NodeRequestId, result.OverallResult);
+                            }
 
                             // Update the configuration with targets information, if we received any and didn't already have it.
                             if (result.DefaultTargets != null)
@@ -515,7 +519,7 @@ public void ReportConfigurationResponse(BuildRequestConfigurationResponse respon
             QueueAction(
                 () =>
                 {
-                    ErrorUtilities.VerifyThrow(_status != BuildRequestEngineStatus.Shutdown && _status != BuildRequestEngineStatus.Uninitialized, "Engine loop not yet started, status is {0}.", _status);
+                    ErrorUtilities.VerifyThrow(_status != BuildRequestEngineStatus.Shutdown && _status != BuildRequestEngineStatus.Uninitialized, "Engine loop not yet started, status is {0}.", _status.Box());
 
                     TraceEngine("Received configuration response for node config {0}, now global config {1}.", response.NodeConfigurationId, response.GlobalConfigurationId);
                     ErrorUtilities.VerifyThrow(_componentHost != null, "No host object set");
@@ -1449,9 +1453,94 @@ private void QueueAction(Action action, bool isLastTask)
             }
         }
 
-        /// <summary>
-        /// Method used for debugging purposes.
-        /// </summary>
+        private void TraceEngine(string format, ulong arg)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, BuildRequestEngineStatus arg2)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2.Box()]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2]);
+            }
+        }
+
+        private void TraceEngine(string format, ulong arg1, ulong arg2)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2, int arg3)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2, arg3]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2, string arg3)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2, arg3]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2, int arg3, string arg4)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2, arg3, arg4]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2, int arg3, BuildRequestEntryState arg4)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2, arg3, arg4]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2, int arg3, int arg4, int arg5)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2, arg3, arg4, arg5]);
+            }
+        }
+
+        private void TraceEngine(string format, int arg1, int arg2, int arg3, int arg4, BuildResultCode arg5)
+        {
+            if (_debugDumpState)
+            {
+                TraceEngine(format, [arg1, arg2, arg3, arg4, arg5]);
+            }
+        }
+
         private void TraceEngine(string format, params object[] stuff)
         {
             if (_debugDumpState)

src/Build/BackEnd/Components/BuildRequestEngine/IBuildRequestEngine.cs

@@ -86,6 +86,38 @@ internal enum BuildRequestEngineStatus
         Shutdown
     }
 
+    /// <summary>
+    /// Provides boxed representations of the <see cref="BuildRequestEngineStatus"/> enumeration values.
+    /// </summary>
+    /// <remarks>This class offers pre-boxed objects for each status value to avoid repeated allocations due to boxing
+    /// when frequently accessing these status values. It also includes an extension method to retrieve the
+    /// boxed object corresponding to a given <see cref="BuildRequestEngineStatus"/>.</remarks>
+    internal static class BuildRequestEngineStatusBoxes
+    {
+        public static readonly object UninitializedBox = BuildRequestEngineStatus.Uninitialized;
+        public static readonly object IdleBox = BuildRequestEngineStatus.Idle;
+        public static readonly object ActiveBox = BuildRequestEngineStatus.Active;
+        public static readonly object WaitingBox = BuildRequestEngineStatus.Waiting;
+        public static readonly object ShutdownBox = BuildRequestEngineStatus.Shutdown;
+
+        /// <summary>
+        /// Gets the canonical boxed object for the specified <see cref="BuildRequestEngineStatus"/>.
+        /// </summary>
+        /// <param name="status">The desired <see cref="BuildRequestEngineStatus"/>.</param>
+        /// <returns>The boxed <see cref="BuildRequestEngineStatus"/>.</returns>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="status"/> is outside the range of
+        /// defined <see cref="BuildRequestEngineStatus"/> values.</exception>
+        public static object Box(this BuildRequestEngineStatus status) => status switch
+        {
+            BuildRequestEngineStatus.Uninitialized => UninitializedBox,
+            BuildRequestEngineStatus.Idle => IdleBox,
+            BuildRequestEngineStatus.Active => ActiveBox,
+            BuildRequestEngineStatus.Waiting => WaitingBox,
+            BuildRequestEngineStatus.Shutdown => ShutdownBox,
+            _ => throw new ArgumentOutOfRangeException(nameof(status)),
+        };
+    }
+
     /// <summary>
     /// Objects implementing this interface may be used by a Node to process build requests
     /// and generate build results.

src/Shared/ErrorUtilities.cs

@@ -196,6 +196,17 @@ internal static void VerifyThrow([DoesNotReturnIf(false)] bool condition, string
             }
         }
 
+        /// <summary>
+        /// Overload for one string format argument.
+        /// </summary>
+        internal static void VerifyThrow([DoesNotReturnIf(false)] bool condition, string unformattedMessage, int arg0)
+        {
+            if (!condition)
+            {
+                ThrowInternalError(unformattedMessage, arg0);
+            }
+        }
+
         /// <summary>
         /// Overload for one string format argument.
         /// </summary>
@@ -207,6 +218,17 @@ internal static void VerifyThrow([DoesNotReturnIf(false)] bool condition, string
             }
         }
 
+        /// <summary>
+        /// Overload for two string format arguments.
+        /// </summary>
+        internal static void VerifyThrow([DoesNotReturnIf(false)] bool condition, string unformattedMessage, int arg0, int arg1)
+        {
+            if (!condition)
+            {
+                ThrowInternalError(unformattedMessage, arg0, arg1);
+            }
+        }
+
         /// <summary>
         /// Overload for two string format arguments.
         /// </summary>