[fpc-devel] Merging identical procedure proposals
J. Gareth Moreton
gareth at moreton-family.com
Sat Oct 16 19:59:20 CEST 2021
Sounds like "procvar = @myproc" would be -O4 at best due to the
side-effects, otherwise I would wonder if it's possible to track such
references, especially with units that are pre-compiled.
Gareth aka. Kit
On 16/10/2021 15:32, Jonas Maebe via fpc-devel wrote:
> On 13/10/2021 19:33, J. Gareth Moreton via fpc-devel wrote:
>> I figure this would be a whole-program optimization though due to
>> inter-unit calls and comparisons and the like.
> Usually this is an optimisation that is performed at link-time because
> you don't need any compiler-level information for it. And then it can
> also consider code from statically linked libraries etc. Most standard
> linkers don't have support for it, but link-time optimisation
> frameworks generally do.
> One thing you have to be mindful of is that if the address of a
> routine gets taken in any way then you cannot merge it anymore,
> because there might be a comparison somewhere in the program such as
> if procvar = @myproc then
> and if myproc gets merged with other routines, then this will return
> true in more cases.
> fpc-devel maillist - fpc-devel at lists.freepascal.org
This email has been checked for viruses by Avast antivirus software.
More information about the fpc-devel