Capturing usage information

[Richard Earnshaw]

On Tue, 2010-08-10 at 10:26 +0100, Dave Martin wrote:
> On Tue, Aug 10, 2010 at 10:16 AM, Loïc Minier <loic.minier at linaro.org> wrote:
> > On Mon, Aug 09, 2010, John Rigby wrote:
> >> Does ltrace do what you want?
> >
> >  This is what comes to my mind as well.
> >
> >  There is a catch: I think eglibc (in fact almost all Ubuntu packages)
> >  is built with -Bsymbolic-functions, which means that you can't
> >  intercept internal calls to memcpy() from other eglibc functions using
> >  LD_PRELOAD.
> 
> memcpy is a particular scary example because the compiler may treat it
> as an intrinsic and/or inline it (as for mem*() and str*() in
> general).

I think that's ok.  We should probably look to see if there are some
cases we don't currently inline, but probably should.  Trivial examples
would include things like moving 4 bytes when the alignment is unknown.
(actually, that's two instructions on v7 if alignment checks in h/w are
turned off).

R.