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From: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
To: "tirtajames45@gmail.com" <tirtajames45@gmail.com>
Cc: 'GNU C Library' <libc-alpha@sourceware.org>
Subject: [PATCH] Avoid double bounds check at the start of the loop
Date: Wed, 6 Sep 2023 10:58:26 +0000	[thread overview]
Message-ID: <PAWPR08MB89827CAA9CCE9678CE8E0A5B83EFA@PAWPR08MB8982.eurprd08.prod.outlook.com> (raw)

Hi James,

So the change you're proposing is correct, but did you benchmark it?
The code is written like it is for a good reason: the checks at the start of
the loop avoid one taken branch per loop iteration. So eventhough there
is an unnecessary branch in the very first iteration, performance actually
improves significantly by doing it this way.

Cheers,
Wilco

             reply	other threads:[~2023-09-06 10:58 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-06 10:58 Wilco Dijkstra [this message]
  -- strict thread matches above, loose matches on Subject: below --
2023-09-04 14:56 James Tirta Halim

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