Unity(JUMBO) build support

Sharpmake.Generators/VisualStudio/ProjectOptionsGenerator.cs

@@ -1052,6 +1052,16 @@ private void GenerateCompilerOptions(IGenerationContext context, ProjectOptionsG
             Options.Option(Options.Vc.Compiler.EnableAsan.Enable, () => { context.Options["EnableASAN"] = "true"; context.CommandLineOptions["EnableASAN"] = "/fsanitize=address"; })
             );
 
+            context.SelectOption
+            (
+            Options.Option(Options.Vc.Compiler.JumboBuild.Disable, () => { context.Options["JumboBuild"] = FileGeneratorUtilities.RemoveLineTag; context.Options["MaxFilesPerJumboFile"] = FileGeneratorUtilities.RemoveLineTag; }),
+            Options.Option(Options.Vc.Compiler.JumboBuild.Enable, () =>
+            {
+                context.Options["JumboBuild"] = "true";
+                context.Options["MaxFilesPerJumboFile"] = context.Configuration.MaxFilesPerJumboFile.ToString();
+            })
+            );
+
             if (context.DevelopmentEnvironment.IsVisualStudio() && context.DevelopmentEnvironment >= DevEnv.vs2017)
             {
                 //Options.Vc.Compiler.DefineCPlusPlus. See: https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/

Sharpmake.Platforms/Sharpmake.CommonPlatforms/BasePlatform.Vcxproj.Template.cs

@@ -180,6 +180,8 @@ public abstract partial class BasePlatform
     <WindowsTargetPlatformVersion>[options.WindowsTargetPlatformVersion]</WindowsTargetPlatformVersion>
     <SpectreMitigation>[options.SpectreMitigation]</SpectreMitigation>
     <EnableASAN>[options.EnableASAN]</EnableASAN>
+    <EnableUnitySupport>[options.JumboBuild]</EnableUnitySupport>
+    <MaxFilesInUnityFile>[options.MaxFilesPerJumboFile]</MaxFilesInUnityFile>
   </PropertyGroup>
 ";
 

Sharpmake/Options.Vc.cs

@@ -1348,6 +1348,20 @@ public enum EnableAsan
                     [DevEnvVersion(minimum = DevEnv.vs2019)]
                     Enable
                 }
+
+                /// <summary>
+                /// Enable Jumbo/Unity builds
+                /// </summary>
+                /// <remarks>
+                /// Merges multiple translation units together
+                /// </remarks>
+                public enum JumboBuild
+                {
+                    [Default]
+                    Disable,
+                    [DevEnvVersion(minimum = DevEnv.vs2019)]
+                    Enable
+                }
             }
 
             public static class CodeAnalysis

Sharpmake/Project.Configuration.cs

@@ -1605,6 +1605,9 @@ public string FastBuildUnityPath
             /// </remarks>
             public bool DoNotGenerateFastBuild = false;
 
+            // Jumbo builds support
+            public int MaxFilesPerJumboFile = 0;
+
             // container for executable
             /// <summary>
             /// Represents a build step that invokes an executable on the file system.