diff --git a/src/coreclr/crossgen-corelib.proj b/src/coreclr/crossgen-corelib.proj
index e0bef5d3b31546..2dc62b8151a3ce 100644
--- a/src/coreclr/crossgen-corelib.proj
+++ b/src/coreclr/crossgen-corelib.proj
@@ -127,6 +127,7 @@
       <CrossGenDllCmd>$(CrossGenDllCmd) --targetarch:$(TargetArchitecture)</CrossGenDllCmd>
       <CrossGenDllCmd>$(CrossGenDllCmd) --targetos:$(TargetOS)</CrossGenDllCmd>
       <CrossGenDllCmd Condition="'$(UsingToolIbcOptimization)' != 'true' and '$(EnableNgenOptimization)' == 'true'">$(CrossGenDllCmd) -m:$(MergedMibcPath) --embed-pgo-data</CrossGenDllCmd>
+      <CrossGenDllCmd>$(CrossGenDllCmd) -O</CrossGenDllCmd>
       <CrossGenDllCmd  Condition="'$(Configuration)' == 'Debug' or '$(Configuration)' == 'Checked'">$(CrossGenDllCmd) --verify-type-and-field-layout</CrossGenDllCmd>
       <CrossGenDllCmd>$(CrossGenDllCmd) @(CoreLib)</CrossGenDllCmd>
     </PropertyGroup>
diff --git a/src/libraries/System.Private.CoreLib/src/System/Text/Ascii.Utility.cs b/src/libraries/System.Private.CoreLib/src/System/Text/Ascii.Utility.cs
index b6b88790ea51f2..ab55607c944c63 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Text/Ascii.Utility.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Text/Ascii.Utility.cs
@@ -2146,8 +2146,7 @@ private static unsafe nuint NarrowUtf16ToAscii_Intrinsified_256(char* pUtf16Buff
             // jumps as much as possible in the optimistic case of "all ASCII". If we see non-ASCII
             // data, we jump out of the hot paths to targets at the end of the method.
 
-            // Commented out to workaround https://github.com/dotnet/runtime/issues/90265
-            // Debug.Assert(Vector256.IsHardwareAccelerated, "Vector256 is required.");
+            Debug.Assert(Vector256.IsHardwareAccelerated, "Vector256 is required.");
             Debug.Assert(BitConverter.IsLittleEndian, "This implementation assumes little-endian.");
             Debug.Assert(elementCount >= 2 * Vector256.Size);
 
diff --git a/src/tests/JIT/Directed/Directed_3.csproj b/src/tests/JIT/Directed/Directed_3.csproj
index 45060cbcc5c871..78ec52b6675c4c 100644
--- a/src/tests/JIT/Directed/Directed_3.csproj
+++ b/src/tests/JIT/Directed/Directed_3.csproj
@@ -14,4 +14,4 @@
   </ItemGroup>
 
   <Import Project="$(TestSourceDir)MergedTestRunner.targets" />
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/tests/issues.targets b/src/tests/issues.targets
index a7a23cd4cdaf3f..9329a8aedbd3e7 100644
--- a/src/tests/issues.targets
+++ b/src/tests/issues.targets
@@ -666,9 +666,6 @@
         <ExcludeList Include="$(XunitTestBinBase)/Interop/StructMarshalling/PInvoke/MarshalStructAsLayoutExp/*">
             <Issue>https://github.com/dotnet/runtime/issues/43461</Issue>
         </ExcludeList>
-        <ExcludeList Include="$(XunitTestBinBase)/JIT/Directed/debugging/poisoning/poison/*">
-            <Issue>https://github.com/dotnet/runtime/issues/56148</Issue>
-        </ExcludeList>
     </ItemGroup>
 
     <!-- Crossgen2 x86 specific excludes -->