Call-stack and exception handling for Windows x64 JIT

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Hi, I use LLVM MCJIT extensively and one of the sore spots is debugging. We lose stack information if we crash during execution of one of our JIT functions. I spent some time to understand Windows x64 stack/exception handling and was able to hardcode support for a single JIT function and was able to maintain the call stack correctly. However it requires knowledge of the prolog of the function to code an UNWIND table used by the OS for stack unwinding, so I’m not sure it’s something I can enable generically as a user of LLVM.

Has there been any progress to enable this support natively in LLVM? If not, I’d be willing to spend some time to enable this functionality, with help from experts in this area of LLVM.

Thanks,
Jason

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This is https://bugs.llvm.org/show_bug.cgi?id=24233. I don’t think there’s been any movement on it for a while. I don’t think it should be hard, but I’ve never really pushed on it.

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Thanks for the bug info. Using the information and patches there, I was able to implement a solution that works for us. I can update the bug with details of the fix. It is quite a happy sight to finally see a complete call stack with our jitted functions in Visual Studio. We even have nested jitted function calls, and they are displaying perfectly.
Thanks again,
Jason