From: Jonathan Wakely <jwakely@redhat.com>
To: "François Dumont" <frs.dumont@gmail.com>
Cc: "libstdc++@gcc.gnu.org" <libstdc++@gcc.gnu.org>,
gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: libstdc++: Extend memcmp optimization in std::lexicographical_compare
Date: Wed, 10 Jun 2020 15:49:05 +0100 [thread overview]
Message-ID: <20200610144905.GL4137376@redhat.com> (raw)
In-Reply-To: <3a40cd2b-81a2-9d7e-30b3-56e538ba5075@gmail.com>
On 10/06/20 08:18 +0200, François Dumont via Libstdc++ wrote:
>On 09/06/20 10:53 pm, Jonathan Wakely wrote:
>>This reminds me that I was going to extend the condition for using
>>memcmp to also apply to unsigned integers with sizeof(T) > 1 on big
>>endian targets.
>>
>This illustrates what I tried to avoid in my original patch, the code
>duplication. I was calling __lexicographical_compare_aux1 because I
>didn't want to duplicate the code to compute __simple.
>
>Of course it can be expose as a template using.
Not for C++98.
I'm not very concerned about duplicating the boolean condition. I
definitely prefer that to codegen changes that affect every user of
lexicographical_compare just to benefit the handful of people using
it with std::deque.
If __lexicographical_compare_aux1 could be reused without changes,
great, but it needed changes with consequences for more code than just
deque iterators.
next prev parent reply other threads:[~2020-06-10 14:49 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-05 20:24 François Dumont
2020-06-08 18:20 ` Jonathan Wakely
2020-06-08 21:08 ` Jonathan Wakely
2020-06-08 23:02 ` Jonathan Wakely
2020-06-09 16:11 ` Jonathan Wakely
2020-06-09 16:12 ` Jonathan Wakely
2020-06-09 20:42 ` François Dumont
2020-06-09 20:53 ` Jonathan Wakely
2020-06-10 6:18 ` François Dumont
2020-06-10 14:49 ` Jonathan Wakely [this message]
2020-06-10 16:40 ` François Dumont
2020-06-10 17:14 ` Jonathan Wakely
2020-06-09 10:24 ` Jonathan Wakely
2020-06-09 20:35 ` François Dumont
2020-06-09 20:50 ` Jonathan Wakely
2020-06-09 20:20 ` François Dumont
2020-06-09 20:38 ` Jonathan Wakely
2020-06-08 20:07 ` Jonathan Wakely
2020-06-08 21:05 ` Jonathan Wakely
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