AV in System.Threading.Tests failing with JitStress

[kunalspathak]

Failing pipeline: https://dev.azure.com/dnceng-public/public/_build/results?buildId=953637&view=ms.vss-test-web.build-test-results-tab&runId=25356914&resultId=217333&paneView=debug

DOTNET_JitStress=159
DOTNET_TieredCompilation=0

C:\h\w\ABD309CB\w\98D40880\e>"C:\h\w\ABD309CB\p\dotnet.exe" exec --runtimeconfig System.Threading.Tests.runtimeconfig.json --depsfile System.Threading.Tests.deps.json xunit.console.dll System.Threading.Tests.dll -xml testResults.xml -nologo -nocolor -notrait category=IgnoreForCI -notrait category=OuterLoop -notrait category=failing  
  Discovering: System.Threading.Tests (method display = ClassAndMethod, method display options = None)
  Discovered:  System.Threading.Tests (found 291 of 303 test cases)
  Starting:    System.Threading.Tests (parallel test collections = on [2 threads], stop on fail = off)
Fatal error. System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
   at System.Threading.Tests.MutexTests.NamedMutex_DisposeWhenLockedRaceTest()
   at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(System.Object, IntPtr*)
   at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(System.Object, System.Reflection.BindingFlags)
   at System.Reflection.RuntimeMethodInfo.Invoke(System.Object, System.Reflection.BindingFlags, System.Reflection.Binder, System.Object[], System.Globalization.CultureInfo)
   at Xunit.Sdk.TestInvoker`1+<>c__DisplayClass47_0+<<InvokeTestMethodAsync>b__1>d[[System.__Canon, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
   at System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[[Xunit.Sdk.TestInvoker`1+<>c__DisplayClass47_0+<<InvokeTestMethodAsync>b__1>d[[System.__Canon, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.execution.dotnet, Version=2.9.2.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]](<<InvokeTestMethodAsync>b__1>d<System.__Canon> ByRef)

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[kunalspathak]

IN0001: 000008      movz    x0, #0xD3A0
IN0002: 00000C      movk    x0, #0xF831 LSL #16
IN0003: 000010      movk    x0, #0x7FFC LSL #32
IN0004: 000014      bl      CORINFO_HELP_NEWSFAST
IN0005: 000018      mov     x1, xzr
IN0006: 00001C      mov     w2, #123
IN0007: 000020      swpalb  w2, w1, [x1]  ;  <-- AV because 2 lines above `x1 == 0`
IN0008: 000024      sxtb    w1, w1
IN0009: 000028      strb    w1, [x0, #0x08]

Edit: The test case that is failing is and it does operate on null and expect to throw. Investigating why it doesn't surface as NullReferenceException instead of AV.

runtime/src/libraries/System.Threading/tests/InterlockedTests.cs

Line 175 in 4dde471

Assert.Throws<NullReferenceException>(() => Interlocked.Exchange(ref Unsafe.NullRef<sbyte>(), 123));

[kunalspathak]

This is same problem as #112709 and fixed in #112711.

 After syncing with Main, the issue disappears as seen below (left= bug, right= main)