llvm dev - Jun 2009 - [LLVMdev] Access a specific address in the JIT compiler

Hi,

I am using the JIT compiler to execute code that must interface with
the running process.
I would like to access some specific addresses.

The solution I found is to create a global variable for each address I
want to reference, and pass it as a mapping to the ExecutionEngine
with addGlobalMapping.

Is that how I should do this?
Is there no way to just reference the addresses with constants?


Best,
Cam

This seems to be the "proper" way to do that.

Another possibility, is to create a ConstantInt with the size of the pointer
(found in TargetData), then do a IntToPtr cast, and use this absolute
address in load/store/call.

Cheers,
Olivier.


On Thu, Jun 11, 2009 at 12:27 PM, Camille Troillard
<camille at osculator.net>wrote:
> Hi,
>
> I am using the JIT compiler to execute code that must interface with
> the running process.
> I would like to access some specific addresses.
>
> The solution I found is to create a global variable for each address I
> want to reference, and pass it as a mapping to the ExecutionEngine
> with addGlobalMapping.
>
> Is that how I should do this?
> Is there no way to just reference the addresses with constants?
>
>
> Best,
> Cam
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
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On Thu, Jun 11, 2009 at 1:17 PM, Olivier
Meurant<meurant.olivier at gmail.com> wrote:
> This seems to be the "proper" way to do that.
>
> Another possibility, is to create a ConstantInt with the size of the
pointer
> (found in TargetData), then do a IntToPtr cast, and use this absolute
> address in load/store/call.
Thanks Olivier, this is what I was looking for.