[clr-ios] Fix exception handling for debugger interception#126955
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kotlarmilos wants to merge 4 commits intodotnet:mainfrom
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[clr-ios] Fix exception handling for debugger interception#126955kotlarmilos wants to merge 4 commits intodotnet:mainfrom
kotlarmilos wants to merge 4 commits intodotnet:mainfrom
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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
InterpreterFrameentries when checking for unhandled exceptions. - Update interpreter breakpoint handling to run pending interpreter func-evals and honor debugger
SetIPchanges 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. |
Contributor
|
Tagging subscribers to 'os-ios': @vitek-karas, @kotlarmilos, @steveisok, @akoeplinger |
This was referenced Apr 15, 2026
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18 tasks
- Skip controlPC -1 adjustment for interpreter methods (bytecode IP already points to the correct instruction boundary) - Detect native transitions past last interpreter frame in SfiNext - Skip InterpreterFrame chain entries when checking for unhandled exceptions Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…rFrame skip - Remove the IsInterpretedCode() skip around controlPC -= STACKWALK_CONTROLPC_ADJUST_OFFSET at both SfiInitWorker and SfiNextWorker exit. The throw-site case is already m_crawl.hasFaulted). The remaining propagation case needs the -1 because pFrame->ip is advanced past the call opcode before descending into the callee, same as a JIT return address, and EH clauses are half-open [tryStart, tryEnd). - Change the InterpreterFrame skip in the isPropagatingToNativeCode branch from while to if. Only the one InterpreterFrame pushed by the just-unwound InterpExecMethod needs bridging; consuming adjacent InterpreterFrames could skip past an outer interpreted catch and incorrectly trigger the unhandled exception path. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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This was referenced Apr 24, 2026
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isn't needed due to #127101, it suppress the debugger filter notification for the UCO entrypoint |
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Description
Fix exception handling paths for the interpreter debugger: detect interpreter-to-native transitions past the last interpreter frame in
SfiNextWorker, and skipInterpreterFrameentries in the unhandled-exception frame chain walk.Follow-up to #126576
This fixes the following interpreter debugger test failure:
Exceptions.InterceptTest