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

[Orzel, Michal]

On 14/07/2025 11:45, Julien Grall wrote:
> 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?
It was in debug build.

~Michal