Enable hosted builds on arm64

To enable building core-setup on arm64 (hosted, not cross compiled), we
need to do a few things:

- Set the right TargetArchitecture

  Use the currently running architecture to decide whether to default to
  x64 or to switch to arm64 when TargetArchitecture is not specified

- Use the right coreclr JIT

  If we are cross-compiling, we need to use the x86_arm64 libclrjit.so.
  But if we are building on an arm64 host, we need to filter the list of
  found libclrjit.so files to pick the normal-RID (eg, linux-arm64)
  libclrjit.so from the two:

    ./.packages/transport.runtime.linux-arm64.microsoft.netcore.jit/###/runtimes/linux-arm64/native/libclrjit.so
    ./.packages/transport.runtime.linux-arm64.microsoft.netcore.jit/###/runtimes/x64_arm64/native/libclrjit.so

- Use a version of SourceLink that supports arm64

  We need to upgrade SourceLink to a version that contains
  dotnet/sourcelink#288. This commit just
  updates it to the latest version.

Fixes #7653

Directory.Build.props

@@ -94,7 +94,9 @@
   </PropertyGroup>
 
   <PropertyGroup>
-    <TargetArchitecture  Condition="'$(TargetArchitecture)' == ''">x64</TargetArchitecture>
+    <HostArch>$([System.Runtime.InteropServices.RuntimeInformation]::ProcessArchitecture)</HostArch>
+    <TargetArchitecture Condition="'$(TargetArchitecture)' == '' AND '$(HostArch)' == 'Arm64'">arm64</TargetArchitecture>
+    <TargetArchitecture Condition="'$(TargetArchitecture)' == ''">x64</TargetArchitecture>
     <Platform Condition="'$(Platform)'==''">$(TargetArchitecture)</Platform>
   </PropertyGroup>
   <!--
@@ -398,4 +400,4 @@
     <DisableImplicitNuGetFallbackFolder>true</DisableImplicitNuGetFallbackFolder>
   </PropertyGroup>
 
-</Project>
+</Project>

eng/Versions.props

@@ -87,7 +87,7 @@
     <MicrosoftTargetingPackPrivateWinRTPackageVersion>1.0.5</MicrosoftTargetingPackPrivateWinRTPackageVersion>
     <MicrosoftDiaSymReaderNativePackageVersion>1.7.0</MicrosoftDiaSymReaderNativePackageVersion>
     <!-- Infrastructure and test-only. -->
-    <MicrosoftSourceLinkVersion>1.0.0-beta2-18618-05</MicrosoftSourceLinkVersion>
+    <MicrosoftSourceLinkVersion>1.0.0-beta2-19367-01</MicrosoftSourceLinkVersion>
   </PropertyGroup>
   <!--Package names-->
   <PropertyGroup>

src/pkg/packaging-tools/framework.dependency.targets

@@ -217,7 +217,8 @@
     <PropertyGroup>
       <_crossDir Condition="'$(TargetArchitecture)' == 'arm' AND '$(OS)' == 'Windows_NT'">/x86_arm</_crossDir>
       <_crossDir Condition="'$(TargetArchitecture)' == 'arm' AND '$(OS)' != 'Windows_NT'">/x64_arm</_crossDir>
-      <_crossDir Condition="'$(TargetArchitecture)' == 'arm64'">/x64_arm64</_crossDir>
+      <!-- Only use x64_arm64 when cross compiling. Use normal executible when compiling on arm64 itself. -->
+      <_crossDir Condition="'$(TargetArchitecture)' == 'arm64' AND '$(HostArch)' != 'Arm64'">/x64_arm64</_crossDir>
     </PropertyGroup>
 
     <ItemGroup>
@@ -251,10 +252,26 @@
     </PropertyGroup>
 
     <PropertyGroup Condition="'@(_runtimeJIT)' != ''">
-      <_jitPath>%(_runtimeJIT.FullPath)</_jitPath>
+      <_runtimeJITFilterDir>$([System.IO.Path]::DirectorySeparatorChar)$(PackageRID)$([System.IO.Path]::DirectorySeparatorChar)</_runtimeJITFilterDir>
+    </PropertyGroup>
+
+    <!-- It is possible for _runtimeJIT to pick up 2 jit files:
+         one for cross compilation and one for native compilation. -->
+    <ItemGroup Condition="'@(_runtimeJIT)' != '' AND '$(_crossDir)' == ''">
+      <_filteredRuntimeJIT Include="%(_runtimeJIT.Identity)" Condition="'@(_runtimeJIT->Contains($(_runtimeJITFilterDir)))' == 'True'" />
+    </ItemGroup>
+
+    <PropertyGroup Condition="'@(_runtimeJIT)' != ''">
+      <_jitPath>%(_filteredRuntimeJIT.FullPath)</_jitPath>
       <_jitPath Condition="'$(_crossDir)' != ''">$(_jitPackageDir)runtimes$(_crossDir)/native/$(LibraryFilePrefix)clrjit$(LibraryFileExtension)</_jitPath>
     </PropertyGroup>
 
+    <Message Importance="high" Text="XXX ### *** === +++ This is PackageRID: $(PackageRID)"/>
+    <Message Importance="high" Text="XXX ### *** === +++ This is _runtimeJIT: @(_runtimeJIT)"/>
+    <Message Importance="high" Text="XXX ### *** === +++ This is _runtimeJITFilterDir: $(_runtimeJITFilterDir)"/>
+    <Message Importance="high" Text="XXX ### *** === +++ This is _filteredRuntimeJIT: @(_filteredRuntimeJIT)"/>
+    <Message Importance="high" Text="XXX ### *** === +++ This is _jitPath: $(_jitPath)"/>
+
     <PropertyGroup Condition="'@(_fxSystemRuntime)' != ''">
       <_fxLibDirectory>%(_fxSystemRuntime.RootDir)%(_fxSystemRuntime.Directory)</_fxLibDirectory>
     </PropertyGroup>