Enable jit optimization in crossgen testing (#114464)

See  #113815 / #113849

Not enabled yet on linux.

Author: AndyAyersMS

src/tests/Common/CLRTest.CrossGen.targets

@@ -110,6 +110,8 @@ if [ ! -z ${RunCrossGen2+x} ]%3B then
         done
 
         echo -o:"$__OutputFile" >> "$__ResponseFile"
+        ## Enable once #114504 is fixed
+        ## echo -O >> "$__ResponseFile"
         echo --targetarch:$(TargetArchitecture) >> "$__ResponseFile"
         echo --targetos:$(TargetOS) >> "$__ResponseFile"
         echo --verify-type-and-field-layout >> "$__ResponseFile"
@@ -276,6 +278,7 @@ if defined RunCrossGen2 (
     set __Command=!__Command! !ExtraCrossGen2Args!
 
     echo !__InputFile!>>!__ResponseFile!
+    echo -O>>!__ResponseFile!
     echo -o:!__OutputFile!>>!__ResponseFile!
     echo --targetarch:$(TargetArchitecture)>>!__ResponseFile!
     echo --targetos:$(TargetOS)>>!__ResponseFile!

src/tests/JIT/Directed/debugging/poisoning/poison.csproj

@@ -3,6 +3,9 @@
     <DebugType>PdbOnly</DebugType>
     <Optimize>False</Optimize>
     <AllowUnsafeBlocks>True</AllowUnsafeBlocks>
+    <!-- Needed for CrossGenTest -->
+    <RequiresProcessIsolation>true</RequiresProcessIsolation>
+    <CrossGenTest>false</CrossGenTest>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="$(MSBuildProjectName).cs" />