Re: [Valgrind-users] how to trace an application

[Nicholas N. <nj...@cs...>]

On Fri, 30 Mar 2007, Josef Weidendorfer wrote:

>>> E.g. you can get a call tree trace with
>>>  valgrind --tool=callgrind --ct-verbose=1 ...
>>
>> That is truly awesome!  It would benefit from strace like command line
>> options and possible a cleaner output format but I can see it being very
>> useful nevertheless.
>
> What about making a new tool out of it?
> It really would be _especially_ nice to print the function parameters with
> correct types, using DWARF debug info.
>
> The call tracing can be extracted as a kind of a module which tools can
> combine. The problem is that every such module could have its own
> instrumentation requirements, and there could be conflicts combining
> multiple instrumentations.
>
> Hmm... perhaps it would be enough for such modules to document their
> instrumentation needs (such as "module X needs a helper call to y at start of
> every BB" or "module X wants to scan the SB and insert an IR snippet
> before every exit"), and let the tool author do the actual instrumentation
> manually as it is done now.

That would be very nice if it could be done in a clean way.  It's one of 
those things that could be useful in a range of contexts but is actually 
really hard to do well, because of all the weird cases (PLT, longjmp/setjmp, 
tail recursion, etc).

Nick