Re: [PATCH] crc: New optimised slice-by-8 implementation

[Simon Josefsson]

Thanks - I am happy with this version, or even without the user-visible logic too (not sure if this is something users should ever tune). My question about selection logic was more for maintainers rather than end-users.

/Simon

27 okt. 2024 kl. 23:04 skrev Sam Russell <sam.h.russell@gmail.com>:



I had a play with autoconf (inspired heavily by m4/debug.m4), can confirm the behaviour works as follows:

# build with slice-by-8 (default enabled)

./configure

make

gltests/bench-crc 1000000

real   1.714850
user   1.715
sys    0.000

# build without slice-by-8

./configure --disable-crc-slice-by-8

make

gltests/bench-crc 1000000
real   7.500251
user   7.500
sys    0.000

I don't know what the "serial" field is for so happy for this to be changed to whatever you like

On Sun, 27 Oct 2024 at 16:56, Bruno Haible <bruno@clisp.org> wrote:

Simon Josefsson wrote:
> I am not certain about the method to enable/disable the optimization,
> is the configure.ac variable the best method we have?

An AC_ARG_ENABLE invocation can be added. Since Sam said that he's not familiar
with Autoconf, it would be your turn to add it...

Bruno

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