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Date: Wed, 24 Feb 2021 18:54:06 +0000
From: Jonathan Wakely <jwakely@redhat.com>
To: Matthias Kretz <m.kretz@gsi.de>
Cc: libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org
Subject: Re: [PATCH 4/4] libstdc++: More efficient last day of month.
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On 23/02/21 23:13 +0100, Matthias Kretz wrote:
>I like the idea.
>
>On Dienstag, 23. Februar 2021 14:25:10 CET Cassio Neri via Libstdc++ wrote:
>> ((__m ^ (__m >> 3)) & 1) | 30
>
>Note that you can drop the `& 1` part. 30 in binary is 0b11110. ORing with a
>value in [0, 0b01101] will only toggle the last bit.

Yeah looks right to me.

I've committed all Cassio's patches unchanged (except for whitespace
and the dates on the tests) but we can make this additional
improvement too.

Thanks, Cassio. Nice first contributions to libstdc++!