[LLVM::IR] How to retrieve llvm::Instruction address after JIT code generation?

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Hi LLVM developers,

I’ve posted yesterday a question on StackOverflow here :

http://stackoverflow.com/questions/42544386/how-to-retrieve-llvminstruction-address-after-jit-code-generation

Is someone knowing the answer ? I would really like to be able to insert manually “int 3” in the generated assembly to add my own JIT software breakpoints.

Thank you !

Sincerely,

Vivien

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(1) Please post your actual question, not just a link to SO.
(2) No, this is generally not possible. LLVM IR doesn't have a 1:1
mapping to assembler and with optimisation, instructions can disappear
or be merged with others. By the nature of SSA, the order of
instructions even within a Basic Block is often not even defined.

You can create debug traps using intrinsics directly.

Joerg

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Sorry for posting the SO question but it seems other people are curious of the answer to that question, and i hoped someone would answer there.

Anyway thank you for your answer !

If I can’t do it that way, I have an alternate question :

Is there a way to retrieve assembly memory address from a llvm::DebugLoc after MCJIT code generation ?
(I guessed it could be possible because GDB can be used with MCJIT)

Thanks!

Vivien

PS: i haven’t got the reply in my mailbox but had to retrieve it in the llvm-dev google group, how can I receive a reply on my mailbox directly ?