Intermittent test crash on linux arm64 caused by FEATURE_STUBPRECODE_DYNAMIC_HELPERS

[jkotas]

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=989940
Build error leg or test failing: HardwareIntrinsics_General_r.WorkItemExecution
Pull request: #113791

Error Message

Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": "",
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

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Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
0	0	0

[jkotas]

I have looked at runfo get-helix-payload -j 483c6874-7256-4cab-8178-20d45a3a2696 -w HardwareIntrinsics_General_r -o c:\helix_payload

We ended up jumping to address 0:

0:000> k
 # Child-SP          RetAddr               Call Site
00 0000e473`0e60de50 0000e4b3`c2b435f0     0x0
01 0000e473`0e60de80 0000e4b3`c2e0ff60     System_Private_CoreLib_e4b3c2840000!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)+0x90
02 0000e473`0e60ded0 0000e4b3`c2d48a14     System_Private_CoreLib_e4b3c2840000!System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.Int32, System.Private.CoreLib],[System.__Canon, System.Private.CoreLib]].MoveNext(System.Threading.Thread)+0x160
03 0000e473`0e60df20 0000e473`0dc038d0     System_Private_CoreLib_e4b3c2840000!System.Threading.Tasks.Sources.ManualResetValueTaskSourceCore`1[[System.Boolean, System.Private.CoreLib]].SignalCompletion()+0x264
...

It is a race condition introduced by #113402 . The code flow

...
0000e4b3`c2e0f0dc 9115616b add         x11,x11,#0x558
0000e4b3`c2e0f0e0 f9400170 ldr         xip0,[x11]
0000e4b3`c2e0f0e4 d63f0200 blr         xip0 // R2R calling dictionary lookup
...

0000e4b3`c42e2fe8 5802004a ldr         x10,0000e4b3`c42e6ff0 // DynamicHelper_GenericDictionaryLookup_Class_TestForNull
0000e4b3`c42e2fec 5801ffec ldr         x12,0000e4b3`c42e6fe8
// This should jump to DynamicHelper_GenericDictionaryLookup_Class_TestForNull
// but it actually jumped to 0 since the code read the value before it was initialized
0000e4b3`c42e2ff0 d61f0140 br          x10

[jkotas]

cc @davidwrighton

[jkotas]

FEATURE_STUBPRECODE_DYNAMIC_HELPERS was disabled in #113811