[clr-ios] Fix exception handling for debugger interception

[kotlarmilos]

Description

Fix exception handling paths for the interpreter debugger: skip the STACKWALK_CONTROLPC_ADJUST_OFFSET adjustment for interpreter methods since the bytecode IP already points at the correct instruction boundary, detect interpreter-to-native transitions past the last interpreter frame in SfiNextWorker, and skip InterpreterFrame entries in the unhandled-exception frame chain walk.

Follow-up to #126576

This fixes the following interpreter debugger test failure:

• Exceptions.InterceptTest

[Copilot]

Pull request overview

Fixes interpreter-related exception/debugger interaction issues (notably exception interception via SetIP) by adjusting EH stack-walking semantics for interpreted frames and enabling interpreter breakpoint handling to resume from debugger-modified IP, with supporting debugger/func-eval plumbing.

Changes:

• Adjust EH stack-walk control PC handling and native-transition detection for interpreted frames, including skipping InterpreterFrame entries when checking for unhandled exceptions.
• Update interpreter breakpoint handling to run pending interpreter func-evals and honor debugger SetIP changes when resuming execution.
• Rename the func-eval flag from “during exception” to “uses hijack” across debugger + CDAC surface area.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Data/Frames/DebuggerEval.cs	Renames CDAC-exposed flag to EvalUsesHijack in the reader contract.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/StackWalk/FrameHandling/X86FrameHandler.cs	Uses EvalUsesHijack to decide whether to update unwind context from DebuggerEval.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/StackWalk/FrameHandling/BaseFrameHandler.cs	Uses EvalUsesHijack to decide whether to update unwind context from DebuggerEval.
src/coreclr/vm/interpexec.cpp	Returns updated bytecode IP from breakpoint callback and executes pending interpreter func-evals.
src/coreclr/vm/exceptionhandling.cpp	Interpreter-aware EH stackwalk changes (controlPC adjust, transition detection, frame-chain skipping).
src/coreclr/vm/dbginterface.h	Adds interpreter-specific debugger hook to execute pending interpreter func-evals.
src/coreclr/vm/datadescriptor/datadescriptor.inc	Updates CDAC data descriptor field name to EvalUsesHijack.
src/coreclr/debug/ee/funceval.cpp	Switches logic from m_evalDuringException to m_evalUsesHijack.
src/coreclr/debug/ee/debugger.h	Renames DebuggerEval state to m_evalUsesHijack and adjusts Init behavior.
src/coreclr/debug/ee/debugger.cpp	Interpreter-aware func-eval setup + new ExecutePendingInterpreterFuncEval implementation; updates to new flag name.

[Copilot]

The CDAC field rename from EvalDuringException to EvalUsesHijack is a breaking contract change for DataContractReader when analyzing dumps from older runtimes (the old field name won’t exist, and ReadField will throw). To preserve backward compatibility, read EvalUsesHijack via ReadFieldOrDefault and, if it’s missing, fall back to reading EvalDuringException (also via ReadFieldOrDefault) and derive EvalUsesHijack = !EvalDuringException.

Suggested change

	EvalUsesHijack = target.ReadField<byte>(address, type, nameof(EvalUsesHijack)) != 0;
	byte? evalUsesHijack = target.ReadFieldOrDefault<byte>(address, type, nameof(EvalUsesHijack));
	if (evalUsesHijack is not null)
	{
	EvalUsesHijack = evalUsesHijack != 0;
	}
	else
	{
	byte? evalDuringException = target.ReadFieldOrDefault<byte>(address, type, "EvalDuringException");
	EvalUsesHijack = evalDuringException is null || evalDuringException == 0;
	}

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