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From: Eelis <eelis@eelis.net>
To: gcc-patches@gcc.gnu.org
Cc: libstdc++ <libstdc++@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: [patch, libstdc++] std::shuffle: Generate two swap positions at a time if possible
Date: Wed, 25 May 2016 20:45:00 -0000	[thread overview]
Message-ID: <5745DD1B.20202@eelis.net> (raw)
Message-ID: <20160525204500.sD__Ksifztg0EeGYtBu8JqSPSv34MDUu00SahZ9QgdU@z> (raw)
In-Reply-To: <5728B8CC.7030405@eelis.net>

>>> On 2016-05-01 16:18, Eelis wrote:
>>>> The attached patch optimizes std::shuffle for the very common case
>>>> where the generator range is large enough that a single invocation
>>>> can produce two swap positions.
>>>>
>>>> This reduces the runtime of the following testcase by 37% on my machine:

Gentle ping. :)  Did anyone get a chance to take a look at this?

Does the idea seem sound? Does the implementation seem correct?

Thanks,

Eelis

  reply	other threads:[~2016-05-25 17:13 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-01 14:18 Eelis
2016-05-01 14:30 ` Eelis
2016-05-03 12:39   ` Jonathan Wakely
2016-05-03 14:42     ` Eelis van der Weegen
2016-05-25 19:54       ` Eelis [this message]
2016-05-25 20:45         ` Eelis
2016-08-31 12:45       ` Jonathan Wakely
2016-09-01 15:14         ` Jonathan Wakely
2016-09-01 15:27           ` Marc Glisse
2016-09-01 15:35             ` Jonathan Wakely
2016-09-01 15:31           ` Eelis van der Weegen
2016-09-01 15:37             ` Jonathan Wakely
2016-09-02 18:20         ` Eelis van der Weegen
2016-09-02 18:53           ` Eelis
2016-09-02 19:27             ` Eelis
2016-10-14 19:42             ` Jonathan Wakely

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