[cDAC] Stackwalking support all Frame types

[max-charlamb]

Frame Support Matrix

	x86	x64	arm	arm64
ResumableFrame	✅	✅	✅	✅
TransitionFrame	✅	✅	✅	✅
FaultingExceptionFrame	✅	✅	✅	✅
SoftwareExceptionFrame	✅	✅	✅	✅
FuncEvalFrame	✅	✅	✅	✅
HijackFrame	✅	✅	✅	✅
InlinedCallFrame	✅	✅	✅	✅
TailCallFrame	✅	-	-	-
InterpreterFrame

Key

✅	Verified
-	Not applicable for platform

Information on Frames

• Support all Frames with NeedsUpdateRegDisplay()==true
  • ResumableFrame [cDAC] Stack walk support more Frame types #112997
    • Stores a PTR_CONTEXT

class RedirectedThreadFrame
{
    public volatile bool flag;
    public volatile int num;

    public RedirectedThreadFrame()
    {
    }

    // Configure WinDBG to break on clr exceptions
    // (sxe clr)
    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    public void Test()
    {
        var cts = new CancellationTokenSource();
        cts.CancelAfter(500);
        
        // use ControlledExecution with a cancellation token to trigger a
        // thread abort with a try/catch
        ControlledExecution.Run(Work, cts.Token);
        while (!flag)
        {
            TestLoop();
        }
    }

    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
    public void TestLoop()
    {
        for (int i = 0; i < 20; i++)
        {
            num++;
        }
    }

    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    public void Work()
    {
        try
        {
            while (!flag)
            {
                TestLoop();
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e);
        }
    }
}

• TransitionFrame [cDAC] Stack walk support more Frame types #112997
  • Stores data in TransitionBlock
  • Tested with PrestubMethodFrame
  • Testing notes: Happens when JITing, set breakpoint during JIT to create a dump.
• FaultingExceptionFrame [cDAC] Stack walk support more Frame types #112997
  • On x86, stores specific registers, otherwise stores a T_CONTEXT
  • Testing notes: Set breakpoint in ThrowControlForThread after it calls InitAndLink. Invoke with a two threaded process where one thread is doing work (loop checking volatile variable) and is cancelled using the following API: Implement ControlledExecution API #71661
  • Invokation through: RedirectForThrowControl2 ASM macro. THROW_CONTROL_FOR_THREAD_FUNCTION

class FaultingExceptionTest
{
    public volatile bool flag;
    public volatile int num;

    public FaultingExceptionTest()
    {
    }

    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    public void Test()
    {
        // bu coreclr!ThrowControlForThread
        Console.ReadLine();
        var cts = new CancellationTokenSource();
        cts.CancelAfter(500);
        ControlledExecution.Run(Work, cts.Token);
        
        while (!flag)
        {
            TestLoop();
        }
    }

    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
    public void TestLoop()
    {
        for (int i = 0; i < 20; i++)
        {
            if (num > 10000)
            {
                Console.WriteLine("num is greater than 10000");
            }
            num++;
        }
    }

    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    public void Work()
    {
        try
        {
            while (!flag)
            {
                TestLoop();
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e);
        }
    }
}

• SoftwareExceptionFrame - [cDAC] Implement core stackwalking #111759
  • Stores a copy of T_CONTEXT
• FuncEvalFrame [cDAC] Stack walk support more Frame types #112997
  • Debugger test app use immediate window to call Console.ReadLine() while it is executing create a dump. Use OS to create a dump (or WinDBG as a non-invasive attach on the debugged process).
  • On ARM, used VS debugging through SSH.
• HelperMethodFrame
  • Stores LazyMachState
  • Planned to be removed.
• HijackFrame [cDAC] Stack walk support more Frame types #112997
  • Set native breakpoint in the GC have second thread doing continuous CPU intensive work (loop checking volatile bool).

class HijackTest()
{
    public volatile bool flag;
    public volatile int num;

    // Set breakpoint at ThreadSuspend::SuspendEE then step out and look at the main thread stack
    // (bu coreclr!ThreadSuspend::SuspendEE)
    // Note: HijackFrames are not used on Windows if CET is enabled. Either test on non-Windows
    // or disable CET by modifying Thread::AreShadowStacksEnabled to return false.
    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    public void Test()
    {
        // start other thread that will force a GC collection.
        Task.Run(Work);

        // run loop checking volatile variable to generate non-interruptible code.
        while (!flag)
        {
            TestLoop();
        }
    }
    public void Work()
    {
        Thread.Sleep(500);
        GC.Collect();
    }

    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
    public void TestLoop()
    {
        num++; num++; num++; num++; num++;
        num++; num++; num++; num++; num++;
        num++; num++; num++; num++; num++;
        num++; num++; num++; num++; num++;
        num++; num++; num++; num++; num++;
        num++; num++; num++; num++; num++;
    }
}

• InlinedCallFrame - [cDAC] Implement core stackwalking #111759
  • Stores IP, SP, and FP directly.
• TailCallFrame (Windows x86 only)

Mostly implemented in #111759 and #112997

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[max-charlamb]

Closing as completed. InterpreterFrame are not supported, but will be another bucket of work to support the interpreter across the cDAC.