[fpc-pascal] Compilation speed on Apple M1

[Michael Van Canneyt]

On Sun, 22 Nov 2020, Florian Klämpfl via fpc-pascal wrote:

> Am 21.11.2020 um 12:54 schrieb Tobias Giesen via fpc-pascal:
>> Hello,
>> 
>> first and foremost, many thanks to the creators and contributors of FPC
>> and Lazarus, who enabled me to release my product natively for Apple
>> Silicon only one day after receiving an M1 Mac. Fantastic work! FPC and
>> Lazarus both run natively and work very well.
>> 
>> According to Geekbench, the single core performance on the new Mac is
>> around 1.8x as fast as my Intel Mac. Multicore is also much faster. I
>> wonder why I don't see the speed increase in compiling though. Yes I am
>> using different FPC and XCode versions, but I wonder what else could
>> have an influence? My project is very large and not divided into
>> packages, so I frequently need to recompile the whole project.
>> 
>> I would be most grateful for any performance tips.
>
> In r47526, I implemented support of the prefetch intrinsic on aarch64. On my 
> Raspi4 it reduced make cycle time by 25 % 
> (!). I would be very interested to get numbers for the M1.

25% ?!

Well... 
If the compiler can make such a difference, should we still bother with micro-optimizations in code then ?

Michael.