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From: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
To: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>,
	James Tirta Halim <tirtajames45@gmail.com>
Cc: "libc-alpha@sourceware.org" <libc-alpha@sourceware.org>
Subject: Re: [PATCH] strcasestr: check if ne[0] is in hs with strchr or strpbrk as does strstr
Date: Mon, 16 Oct 2023 13:52:07 +0000	[thread overview]
Message-ID: <PAWPR08MB8982DFAAA7ED14F6EECC0E8E83D7A@PAWPR08MB8982.eurprd08.prod.outlook.com> (raw)
In-Reply-To: <8deea669-21b6-442b-a58a-05be075290a8@linaro.org>

Hi Adhemerval/James,

> We have the sysdep folder exactly to provide such macros if requires, for instance
> the file sysdeps/generic/string-fzi.h.
>
> So if this optimization is really worth, the best way to provide would be through
> a generic implementation like:

I ran it on my x86 machine (with proper AVX-512), and the "optimized" strcspn is
slower than the simple byte loop on bench-strcasestr. While the benchmark could
likely be improved, it shows this target specific optimization isn't worth doing.

Cheers,
Wilco

  reply	other threads:[~2023-10-16 13:52 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-07 22:14 Wilco Dijkstra
2023-10-14  8:32 ` James Tirta Halim
2023-10-16 12:59   ` Adhemerval Zanella Netto
2023-10-16 13:52     ` Wilco Dijkstra [this message]
2023-10-16 16:56       ` Noah Goldstein
2023-10-17  9:57         ` Wilco Dijkstra
2023-10-14  8:56 ` [PATCH 1/2] " James Tirta Halim
2023-11-28 14:01 ` [PATCH] strcasestr: try to find non-alpha char in NEEDLE James Tirta Halim
2023-12-04 14:44   ` Carlos O'Donell
  -- strict thread matches above, loose matches on Subject: below --
2023-09-06 17:42 [PATCH] strcasestr: check if ne[0] is in hs with strchr or strpbrk as does strstr James Tirta Halim

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