[fpc-pascal] Cache-line alignment for records

[Jonas Maebe]

On 27/03/2023 09:28, Matias Ezequiel Vara Larsen via fpc-pascal wrote:
> Apologies in the case this subject has been already discussed. I require
> that some global variables be cache-line aligned. This is a requirement
> for per-CPU variables that are statically defined to prevent cache
> ping-pong. Is there any way to do this at fpc when the record is
> declared?

{$push}
{$codealign varmin=16}
{$codealign constmin=16}
const
   constdata: array[0..3] of longint = (1,2,3,4);

var
   x: array[0..15] of longint;
{$pop}

However, the maximum alignment you can specify this way is limited per 
target (hardcoded in the compiler). In 3.2.x, it's 16 bytes for most 
desktop targets. On 3.3.x, it's 64 bytes for most desktop targets.


Jonas