Re: define pg_structiszero(addr, s, r)

Hi,

On Wed, Nov 06, 2024 at 01:44:58PM +0900, Michael Paquier wrote:
> Should the last loop check only 1 byte at a time or should this stuff
> include one more step before the last one you wrote to do a couple of
> checks with size_t? That may matter for areas small enough (len <
> sizeof(size_t) * 8) causing the second step to not be taken, but large
> enough (len > sizeof(size_t)) to apply a couple of size_t checks per
> loop.

Do you mean add:

"
for (; p < aligned_end; p += sizeof(size_t))
{
if (*(size_t *)p != 0)
return false;
}
"

just before the last loop?

If so, I did a few tests and did not see any major improvements. So, I thought
it's simpler to not add more code in this inline function in v7 shared up-thread.

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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