[LLVMdev] want to intercept array dereferences

[Jeremy Lakeman]

You might be able to match the GEP + load pair and replace with a call.
But, it would depend entirely on how the llvm instructions were generated
and what optimisations have been run.

On Wed, Apr 8, 2015 at 3:54 PM, Gry Gunvor <gry.gunvor at gmail.com> wrote:

> If I understand correctly, LLVM is a *typed* assembly language.  Could
> I just look for a pointer type plus an integer type followed by a
> dereference?  That would catch both a[n] and *(a+n).
> Gry
>
>
> On Tue, Apr 7, 2015 at 10:46 PM, Bruce Hoult <bruce at hoult.org> wrote:
> > Far too late. That would need to be in Clang.
> >
> > On Wed, Apr 8, 2015 at 5:36 PM, Gry Gunvor <gry.gunvor at gmail.com> wrote:
> >>
> >> Normally for int n unknown at static time, "a[n]" and "*(a+n)" results
> >> in an add and then a dereference.  I want instead for it to compile to
> >> a system call that takes two arguments, a and n.  Where should I
> >> intercept this in LLVM?
> >>
> >> Gry
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