llvm dev - Mar 2007 - [LLVMdev] Address of an instruction (or a label?)

Hello, Nicolas.
> Is there a way in llvm to get the address of a generated instruction? Or 
> somehow to fix the location of a label in the llvm code (something that 
> may look like a basic block perhaps) and get after the compilation the 
> address of this label?
Maybe it's worth to use llvm.dbg.stoppoint?

-- 
With best regards, Anton Korobeynikov.

Faculty of Mathematics & Mechanics, Saint Petersburg State University.

I agree.  Instead of using line numbers, with llvm.dbg.stoppoint, you  
could use the byte code index.  Or alternatively, you could use the  
column number field instead (not currently managed by  
MachineModuleInfo.)  In the backend, you can generate a machine  
instruction to byte code mapping table from queries to   
MachineModuleInfo.

Cheers,

-- Jim





On 12-Mar-07, at 8:34 AM, Anton Korobeynikov wrote:
> Hello, Nicolas.
>
>> Is there a way in llvm to get the address of a generated  
>> instruction? Or
>> somehow to fix the location of a label in the llvm code (something  
>> that
>> may look like a basic block perhaps) and get after the compilation  
>> the
>> address of this label?
> Maybe it's worth to use llvm.dbg.stoppoint?
>
> -- 
> With best regards, Anton Korobeynikov.
>
> Faculty of Mathematics & Mechanics, Saint Petersburg State University.
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev

Hi Anton,

Anton Korobeynikov wrote:
> Maybe it's worth to use llvm.dbg.stoppoint?
>
>   
Do you have an example on how to use this intrinsic with the JIT? How 
can I get at compile
time the address of the stoppoint?

Thx,
Nicolas

After chatting with Anton, we realized that this was actually not a 
solution because
it is not implemented in the JIT.

Let me turn the question with a different angle : is there a way in llvm 
to force the emission of
basic blocks labels, even ones that are useless, eg:

        load 1
        load 2  
        add
        branch label "foo"
foo:  load 4

And there is no other jump to the "foo" label. Actually in llvm the 
label is just removed and the basic block
does not get a native address after compilation.

Cheers,
Nicolas

Nicolas Geoffray wrote:
> Hi Anton,
>
> Anton Korobeynikov wrote:
>   
>> Maybe it's worth to use llvm.dbg.stoppoint?
>>
>>   
>>     
>
> Do you have an example on how to use this intrinsic with the JIT? How 
> can I get at compile
> time the address of the stoppoint?
>
> Thx,
> Nicolas
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>