illink.targets

<Project>
  <PropertyGroup>
    <TargetsTriggeredByCompilation Condition="'$(DesignTimeBuild)' != 'true'">
      $(TargetsTriggeredByCompilation);
      _SetILLinkTrimAssembly;
      ILLinkTrimAssembly
    </TargetsTriggeredByCompilation>
  </PropertyGroup>

  <!-- Inputs and outputs of ILLinkTrimAssembly -->
  <PropertyGroup>
    <ILLinkTasksDir>$([MSBuild]::NormalizeDirectory('$(PkgILLink_Tasks)', 'tools'))</ILLinkTasksDir>
    <ILLinkTasksPath Condition="'$(ILLinkTasksPath)' == '' and '$(MSBuildRuntimeType)' == 'core'">$(ILLinkTasksDir)netcoreapp3.0/ILLink.Tasks.dll</ILLinkTasksPath>
    <ILLinkTasksPath Condition="'$(ILLinkTasksPath)' == '' and '$(MSBuildRuntimeType)' != 'core'">$(ILLinkTasksDir)$(NetFrameworkCurrent)/ILLink.Tasks.dll</ILLinkTasksPath>
    <ILLinkTrimAssemblyPath>$(IntermediateOutputPath)$(TargetName)$(TargetExt)</ILLinkTrimAssemblyPath>
    <ILLinkTrimAssemblySymbols>$(IntermediateOutputPath)$(TargetName).pdb</ILLinkTrimAssemblySymbols>
    <ILLinkTrimInputPath>$(IntermediateOutputPath)PreTrim/</ILLinkTrimInputPath>
    <ILLinkTrimInputAssembly>$(ILLinkTrimInputPath)$(TargetName)$(TargetExt)</ILLinkTrimInputAssembly>
    <ILLinkTrimInputSymbols>$(ILLinkTrimInputPath)$(TargetName).pdb</ILLinkTrimInputSymbols>
    <ILLinkTrimOutputPath>$(IntermediateOutputPath)</ILLinkTrimOutputPath>

    <ILLinkTrimXml Condition="'$(ILLinkTrimXml)' == '' and Exists('$(MSBuildProjectDirectory)/ILLinkTrim.xml')">$(MSBuildProjectDirectory)/ILLinkTrim.xml</ILLinkTrimXml>

    <!-- if building a PDB, tell illink to rewrite the symbols file -->
    <ILLinkRewritePDBs Condition="'$(ILLinkRewritePDBs)' == '' and '$(DebugSymbols)' != 'false'">true</ILLinkRewritePDBs>
  </PropertyGroup>

  <ItemGroup Condition="'$(ILLinkTrimXml)' != ''">
    <EmbeddedResource Include="$(ILLinkTrimXml)">
      <LogicalName>$(AssemblyName).xml</LogicalName>
    </EmbeddedResource>
  </ItemGroup>

  <!-- Custom binplacing for pre/post-trimming and reports that is useful for analysis 
       Must be enabled by setting BinPlaceILLinkTrimAssembly=true
  --> 
  <ItemGroup Condition="'$(BinPlaceILLinkTrimAssembly)' == 'true'">
    <BinPlaceTargetFramework Include="$(BuildSettings)">
      <RuntimePath>$(ArtifactsBinDir)ILLinkTrimAssembly/$(BuildSettings)/trimmed</RuntimePath>
      <ItemName>TrimmedItem</ItemName>
    </BinPlaceTargetFramework>
    <BinPlaceTargetFramework Include="$(BuildSettings)">
      <RuntimePath>$(ArtifactsBinDir)ILLinkTrimAssembly/$(BuildSettings)/reports</RuntimePath>
      <ItemName>TrimmingReport</ItemName>
    </BinPlaceTargetFramework>
    <BinPlaceTargetFramework Include="$(BuildSettings)">
      <RuntimePath>$(ArtifactsBinDir)ILLinkTrimAssembly/$(BuildSettings)/pretrimmed</RuntimePath>
      <ItemName>PreTrimmedItem</ItemName>
    </BinPlaceTargetFramework>
  </ItemGroup>

  <Target Name="_SetILLinkTrimAssembly" 
          Condition="'$(ILLinkTrimAssembly)' == ''"
          DependsOnTargets="GetBinPlaceTargetFramework">
    <PropertyGroup>
      <!-- Currently ILLink cannot handle type projections from Windows.winmd, disable if the project references it -->
      <ILLinkTrimAssembly Condition="'%(ReferencePath.FileName)%(ReferencePath.Extension)' == 'Windows.winmd'">false</ILLinkTrimAssembly>
    </PropertyGroup>
  </Target>

  <!-- ILLinkTrimAssembly
       Examines the "input assembly" for IL that is unreachable from public API and trims that,
       rewriting the assembly to an "output assembly"
  -->
  <UsingTask TaskName="ILLink" AssemblyFile="$(ILLinkTasksPath)" />
  <Target Name="ILLinkTrimAssembly" Condition="'$(ILLinkTrimAssembly)' == 'true'">
    <PropertyGroup>
      <ILLinkArgs>$(ILLinkArgs)-r $(TargetName)</ILLinkArgs>
      <!-- default action for core assemblies -->
      <ILLinkArgs>$(ILLinkArgs) -c skip</ILLinkArgs>
      <!-- default action for non-core assemblies -->
      <ILLinkArgs>$(ILLinkArgs) -u skip</ILLinkArgs>
      <!-- trim the target assembly -->
      <ILLinkArgs>$(ILLinkArgs) -p link $(TargetName)</ILLinkArgs>
      <!-- keep type-forward assemblies (facades) -->
      <ILLinkArgs>$(ILLinkArgs) -t</ILLinkArgs>
      <ILLinkArgs Condition="'$(ILLinkRewritePDBs)' == 'true' and Exists('$(ILLinkTrimAssemblySymbols)')">$(ILLinkArgs) -b true</ILLinkArgs>
      <!-- keep types and members required by Debugger-related attributes -->
      <ILLinkArgs>$(ILLinkArgs) -v true</ILLinkArgs>
      <!-- don't remove the embedded root xml resource since ILLink may run again on the assembly -->
      <ILLinkArgs>$(ILLinkArgs) --strip-resources false</ILLinkArgs>
      <!-- ignore unresolved references -->
      <ILLinkArgs>$(ILLinkArgs) --skip-unresolved true</ILLinkArgs>
      <!-- keep interface implementations -->
      <ILLinkArgs>$(ILLinkArgs) --disable-opt unusedinterfaces</ILLinkArgs>
      <!-- disable optimization to unblock dependencies bump -->
      <ILLinkArgs>$(ILLinkArgs) --disable-opt ipconstprop</ILLinkArgs>
      <!-- keep PreserveDependencyAttribute unless a project explicitly disables it -->
      <ILLinkArgs Condition="'$(ILLinkKeepDepAttributes)' != 'false'">$(ILLinkArgs) --keep-dep-attributes true</ILLinkArgs>
    </PropertyGroup>

    <MakeDir Directories="$(ILLinkTrimInputPath)" />

    <!-- Move the assembly into a subdirectory for ILLink -->
    <Move SourceFiles="$(ILLinkTrimAssemblyPath)"
          DestinationFolder="$(ILLinkTrimInputPath)"
    />

    <!-- Move the PDB into a subdirectory for ILLink if we are rewriting PDBs -->
    <Move SourceFiles="$(ILLinkTrimAssemblySymbols)"
          DestinationFolder="$(ILLinkTrimInputPath)"
          Condition="'$(ILLinkRewritePDBs)' == 'true' and Exists('$(ILLinkTrimAssemblySymbols)')"
    />

    <ItemGroup>
      <_DependencyDirectoriesTemp Include="@(ReferencePath->'%(RootDir)%(Directory)')" />
      <!-- Remove duplicate directories by batching over them -->
      <!-- Add project references first to give precedence to project-specific files -->
      <_DependencyDirectories Condition="'%(_DependencyDirectoriesTemp.ReferenceSourceTarget)'=='ProjectReference'" Include="%(_DependencyDirectoriesTemp.Identity)" />
      <_DependencyDirectories Condition="'%(_DependencyDirectoriesTemp.ReferenceSourceTarget)'!='ProjectReference'" Include="%(_DependencyDirectoriesTemp.Identity)" />
      <!-- Remove trailing slash to work around response file parsing behavior -->
      <_DependencyDirectoriesSlash Include="@(_DependencyDirectories)">
        <PathWithSlash>$([MSBuild]::EnsureTrailingSlash('%(Identity)'))</PathWithSlash>
      </_DependencyDirectoriesSlash>
      <_DependencyDirectoriesNoSlash Include="@(_DependencyDirectoriesSlash)">
        <PathWithoutSlash>$([System.String]::new('%(PathWithSlash)').TrimEnd($([System.IO.Path]::DirectorySeparatorChar)))</PathWithoutSlash>
      </_DependencyDirectoriesNoSlash>
      <_DependencyDirectories Remove="@(_DependencyDirectories)" />
      <_DependencyDirectories Include="%(_DependencyDirectoriesNoSlash.PathWithoutSlash)" />
    </ItemGroup>

    <PropertyGroup>
      <ILLinkArgs Condition="@(_DependencyDirectories->Count()) > 0">$(ILLinkArgs) -d @(_DependencyDirectories->'"%(Identity)"', ' -d ')</ILLinkArgs>
    </PropertyGroup>

    <!-- When running from Desktop MSBuild, DOTNET_HOST_PATH is not set.
         In this case, explicitly specify the path to the dotnet host. -->
    <PropertyGroup Condition=" '$(DOTNET_HOST_PATH)' == '' ">
      <_DotNetHostDirectory>$(NetCoreRoot)</_DotNetHostDirectory>
      <_DotNetHostFileName>dotnet</_DotNetHostFileName>
      <_DotNetHostFileName Condition=" '$(OS)' == 'Windows_NT' ">dotnet.exe</_DotNetHostFileName>
    </PropertyGroup>
    
    <ILLink AssemblyPaths="$(ILLinkTrimInputAssembly)"
            RootAssemblyNames=""
            OutputDirectory="$(ILLinkTrimOutputPath)"
            ClearInitLocals="$(ILLinkClearInitLocals)"
            ClearInitLocalsAssemblies="$(TargetName)"
            ExtraArgs="$(ILLinkArgs)"
            ToolExe="$(_DotNetHostFileName)"
            ToolPath="$(_DotNetHostDirectory)" />

  </Target>

  <!-- ILLink reporting.
       Only enabled when developer specifies a path to the AsmDiff tool with property AsmDiffCmd.
       EG: AsmDiffCmd=d:\tools\asmdiff\asmdiff.exe
       This is necessary until the AsmDiff tool is ported to .NET Core. -->
  <Target Name="_CreateILLinkTrimAssemblyReports"
          AfterTargets="ILLinkTrimAssembly"
          Condition="'$(AsmDiffCmd)' != ''">
    <PropertyGroup>
      <AsmDiffArgs>$(AsmDiffArgs) $(ILLinkTrimInputAssembly)</AsmDiffArgs>
      <AsmDiffArgs>$(AsmDiffArgs) $(ILLinkTrimAssemblyPath)</AsmDiffArgs>
      <AsmDiffArgs>$(AsmDiffArgs) -includePrivateApis -includeInternalApis -alwaysDiffMembers -diffAttributes</AsmDiffArgs>

      <AsmDiffReport>$(IntermediateOutputPath)$(TargetName).diff.html</AsmDiffReport>
      <AsmDiffReportArgs>$(AsmDiffArgs) -out:$(AsmDiffReport)</AsmDiffReportArgs>
      <AsmDiffReportArgs>$(AsmDiffReportArgs) -unchanged -changed -added -removed</AsmDiffReportArgs>

      <AsmDiffList>$(IntermediateOutputPath)$(TargetName).diff.csv</AsmDiffList>
      <AsmDiffListArgs>$(AsmDiffArgs) -out:$(AsmDiffList)</AsmDiffListArgs>
      <AsmDiffListArgs>$(AsmDiffListArgs) -unchanged -changed -added -removed </AsmDiffListArgs>
      <AsmDiffListArgs>$(AsmDiffListArgs) -diffWriter:CSV</AsmDiffListArgs>
    </PropertyGroup>

    <Exec Command="$(AsmDiffCmd) $(AsmDiffReportArgs)" />
    <Message Text="Assembly trimming diff: $(AsmDiffReport)" />
    <Exec Command="$(AsmDiffCmd) $(AsmDiffListArgs)" />
    <Message Text="Assembly trimming report: $(AsmDiffList)" />
  </Target>
  
  <!-- Similar to _CheckForCompileOutputs and runs in the same places, 
       always set these even if compile didn't run. -->
  <Target Name="_CheckForILLinkTrimAssemblyOutputs" 
          BeforeTargets="CopyFilesToOutputDirectory;_CleanGetCurrentAndPriorFileWrites"
          Condition="'$(ILLinkTrimAssembly)' == 'true'">
    <ItemGroup>
      <PreTrimmedItem Condition="Exists('$(ILLinkTrimInputAssembly)')" Include="$(ILLinkTrimInputAssembly)" />
      <PreTrimmedItem Condition="'$(ILLinkRewritePDBs)' == 'true' and Exists('$(ILLinkTrimInputSymbols)')" Include="$(ILLinkTrimInputSymbols)" />
      <FileWrites Include="@(PreTrimmedItem)" />

      <TrimmedItem Condition="Exists('$(ILLinkTrimAssemblyPath)')" Include="$(ILLinkTrimAssemblyPath)" />
      <TrimmedItem Condition="'$(ILLinkRewritePDBs)' == 'true' and Exists('$(ILLinkTrimAssemblySymbols)')" Include="$(ILLinkTrimAssemblySymbols)" />

      <TrimmingReport Condition="Exists('$(AsmDiffReport)')" Include="$(AsmDiffReport)" />
      <TrimmingReport Condition="Exists('$(AsmDiffList)')" Include="$(AsmDiffList)" />
    </ItemGroup>
  </Target>
</Project>