Re: [PATCH 2/2] xen/arm: Skip loops in init_pdx() when no PDX compression is used

[Julien Grall <julien@xxxxxxx>]

Hi Michal,

On 14/07/2025 08:37, Orzel, Michal wrote:
> On 12/07/2025 12:29, Julien Grall wrote:
> > Hi Michal,
> >
> > On 04/07/2025 08:54, Michal Orzel wrote:
> > > When CONFIG_PDX_COMPRESSION=n, pdx_init_mask(), pdx_region_mask() and
> > > pfn_pdx_hole_setup() are just stubs doing nothing. It does not make
> > > sense to keep the two loops iterating over all the memory banks.
> > I saw this was already committed. But I have a question. Wouldn't the
> > compiler be able to optimize and remove the loops? Asking because we are
> > trying to limit the number of #ifdef in the code hence why we have stubs.
> Before submitting a patch I did disassembled init_pdx() with and without my
> patch and in the latter case the compiler did not optimize out the loops.
One more question. Was this in debug or non-debug build?

Cheers,

--
Julien Grall