Add empty benchmark project.

osu.Desktop.slnf

@@ -3,6 +3,7 @@
     "path": "osu.sln",
     "projects": [
       "osu.Desktop\\osu.Desktop.csproj",
+      "osu.Game.Benchmarks\\osu.Game.Benchmarks.csproj",
       "osu.Game.Rulesets.Catch.Tests\\osu.Game.Rulesets.Catch.Tests.csproj",
       "osu.Game.Rulesets.Catch\\osu.Game.Rulesets.Catch.csproj",
       "osu.Game.Rulesets.Mania.Tests\\osu.Game.Rulesets.Mania.Tests.csproj",

osu.Game.Benchmarks/Program.cs

@@ -0,0 +1,13 @@
+// Copyright (c) ppy Pty Ltd <[email protected]>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+namespace osu.Game.Benchmarks
+{
+    public static class Program
+    {
+        public static void Main(string[] args)
+        {
+
+        }
+    }
+}

osu.Game.Benchmarks/osu.Game.Benchmarks.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <OutputType>Exe</OutputType>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+</Project>

osu.sln

@@ -65,6 +65,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		osu.TestProject.props = osu.TestProject.props
 	EndProjectSection
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "osu.Game.Benchmarks", "osu.Game.Benchmarks\osu.Game.Benchmarks.csproj", "{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -399,6 +401,18 @@ Global
 		{5CC222DC-5716-4499-B897-DCBDDA4A5CF9}.Release|iPhoneSimulator.ActiveCfg = Release|Any CPU
 		{5CC222DC-5716-4499-B897-DCBDDA4A5CF9}.Release|iPhoneSimulator.Build.0 = Release|Any CPU
 		{5CC222DC-5716-4499-B897-DCBDDA4A5CF9}.Release|iPhoneSimulator.Deploy.0 = Release|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Debug|iPhone.ActiveCfg = Debug|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Debug|iPhone.Build.0 = Debug|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Debug|iPhoneSimulator.ActiveCfg = Debug|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Debug|iPhoneSimulator.Build.0 = Debug|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Release|Any CPU.Build.0 = Release|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Release|iPhone.ActiveCfg = Release|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Release|iPhone.Build.0 = Release|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Release|iPhoneSimulator.ActiveCfg = Release|Any CPU
+		{93632F2D-2BB4-46C1-A7B8-F8CF2FB27118}.Release|iPhoneSimulator.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE