Re: Cost of handling misaligned access

Liste des GroupesRevenir à c arch 
Sujet : Re: Cost of handling misaligned access
De : already5chosen (at) *nospam* yahoo.com (Michael S)
Groupes : comp.arch
Date : 10. Feb 2025, 11:23:52
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <20250210122352.000050fc@yahoo.com>
References : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
User-Agent : Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-w64-mingw32)
On Sat, 08 Feb 2025 08:11:04 GMT
anton@mips.complang.tuwien.ac.at (Anton Ertl) wrote:

 
keylocks3.c compiles without warning on clang, but the result usually
segfaults (but sometime does not, e.g., in the timed run on Zen4; it
segfaults in other runs on Zen4).  I have not investigated why this
happens, I just did not include results from runs where it segfaulted;
and I tried additional runs for keylocks3-512 on Zen4 in order to have
one result there.
 

I got random crashes both on keylocks3.c and on keylocks4.c.
My test bench includes testing of 1024 combinations of key and lock
lengths, so it likely catches some problematic cases in keylocks4.c.
that you overlooked.
The fix appears to be addition of alignment requirement for locks1[].
  _Alignas(UNROLL*4) int locks1[nlocks1];
Cleaner solution is to declare locks1[] as
 vu locks1[nlocks1/UNROLL];
But I wanted to modify your code as little as possible.


 


Date Sujet#  Auteur
3 Feb 25 * Re: Cost of handling misaligned access106Anton Ertl
3 Feb 25 +- Re: Cost of handling misaligned access9BGB
23 Apr 26 +- 
4 Feb 25 +* Re: Cost of handling misaligned access40Anton Ertl
5 Feb 25 i`* Re: Cost of handling misaligned access39Terje Mathisen
5 Feb 25 i +* Re: Cost of handling misaligned access4Anton Ertl
5 Feb 25 i i+* Re: Cost of handling misaligned access2Terje Mathisen
6 Feb 25 i ii`- Re: Cost of handling misaligned access1Anton Ertl
6 Feb 25 i i`- Re: Cost of handling misaligned access1Anton Ertl
5 Feb 25 i `* Re: Cost of handling misaligned access34Michael S
6 Feb 25 i  +* Re: Cost of handling misaligned access32Anton Ertl
6 Feb 25 i  i`* Re: Cost of handling misaligned access31Michael S
6 Feb 25 i  i +* Re: Cost of handling misaligned access2Anton Ertl
6 Feb 25 i  i i`- Re: Cost of handling misaligned access1Michael S
6 Feb 25 i  i `* Re: Cost of handling misaligned access28Terje Mathisen
6 Feb 25 i  i  `* Re: Cost of handling misaligned access27Terje Mathisen
6 Feb 25 i  i   `* Re: Cost of handling misaligned access26Michael S
6 Feb 25 i  i    `* Re: Cost of handling misaligned access25Terje Mathisen
6 Feb 25 i  i     +* Re: Cost of handling misaligned access19Michael S
7 Feb 25 i  i     i`* Re: Cost of handling misaligned access18Terje Mathisen
7 Feb 25 i  i     i `* Re: Cost of handling misaligned access17Michael S
7 Feb 25 i  i     i  `* Re: Cost of handling misaligned access16Terje Mathisen
7 Feb 25 i  i     i   `* Re: Cost of handling misaligned access15Michael S
7 Feb 25 i  i     i    +- Re: Cost of handling misaligned access1Terje Mathisen
7 Feb 25 i  i     i    +* Re: Cost of handling misaligned access3MitchAlsup1
8 Feb 25 i  i     i    i+- Re: Cost of handling misaligned access1Terje Mathisen
8 Feb 25 i  i     i    i`- Re: Cost of handling misaligned access1Michael S
8 Feb 25 i  i     i    `* Re: Cost of handling misaligned access10Anton Ertl
8 Feb 25 i  i     i     +- Re: Cost of handling misaligned access1Terje Mathisen
8 Feb 25 i  i     i     +* Re: Cost of handling misaligned access6Michael S
8 Feb 25 i  i     i     i`* Re: Cost of handling misaligned access5Anton Ertl
8 Feb 25 i  i     i     i +- Re: Cost of handling misaligned access1Michael S
9 Feb 25 i  i     i     i +* Re: Cost of handling misaligned access2Michael S
11 Feb 25 i  i     i     i i`- Re: Cost of handling misaligned access1Michael S
9 Feb 25 i  i     i     i `- Re: Cost of handling misaligned access1Michael S
9 Feb 25 i  i     i     +- Re: Cost of handling misaligned access1Michael S
10 Feb 25 i  i     i     `- Re: Cost of handling misaligned access1Michael S
7 Feb 25 i  i     `* Re: Cost of handling misaligned access5BGB
7 Feb 25 i  i      `* Re: Cost of handling misaligned access4MitchAlsup1
7 Feb 25 i  i       `* Re: Cost of handling misaligned access3BGB
8 Feb 25 i  i        `* Re: Cost of handling misaligned access2Anssi Saari
8 Feb 25 i  i         `- Re: Cost of handling misaligned access1BGB
6 Feb 25 i  `- Re: Cost of handling misaligned access1Terje Mathisen
6 Feb 25 `* Re: Cost of handling misaligned access5Waldek Hebisch
6 Feb 25  +* Re: Cost of handling misaligned access3Anton Ertl
6 Feb 25  i`* Re: Cost of handling misaligned access2Waldek Hebisch
6 Feb 25  i `- Re: Cost of handling misaligned access1Anton Ertl
6 Feb 25  `- Re: Cost of handling misaligned access1Terje Mathisen

Haut de la page

Les messages affichés proviennent d'usenet.

NewsPortal