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Programming => General => Topic started by: julkas on June 06, 2020, 06:25:59 am

Title: [SOLVED] __builtin_prefetch
Post by: julkas on June 06, 2020, 06:25:59 am

I need  C  __builtin_prefetch analog.
Any hint?

Title: Re: __builtin_prefetch
Post by: Thaddy on June 06, 2020, 10:30:34 am

isn't it just (intel/amd):

Code: Pascal  [Select][+][-]

1. procedure prefetch;inline;asm prefetch;end;

Note that prefetch is not very useful on modern processors.
(But it had a marked improvement on old amd64.)

Title: Re: __builtin_prefetch
Post by: PascalDragon on June 06, 2020, 11:01:33 am

Quote from: julkas on June 06, 2020, 06:25:59 am

I need  C  __builtin_prefetch analog.
Any hint?

It's simply called Prefetch (https://www.freepascal.org/docs-html/current/rtl/system/prefetch.html). It will only have an effect on x86 (all three bitnesses), PowerPC (both bitnesses) and ARM as only there it's backend is implemented. On other platforms won't have an effect.

Title: Re: __builtin_prefetch
Post by: julkas on June 06, 2020, 11:45:53 am

Quote from: PascalDragon on June 06, 2020, 11:01:33 am

It's simply called Prefetch (https://www.freepascal.org/docs-html/current/rtl/system/prefetch.html).

Thanks.