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From: Jonathan Wakely <jwakely.gcc@gmail.com>
Date: Tue, 3 Aug 2021 21:59:43 +0100
Message-ID: <CAH6eHdSH9uOpOLrH37qztYe=eRpdX=iWSYkzAaC4EOZio9ekwA@mail.gmail.com>
Subject: Re: [PATCH] libstdc++: Skip atomic instructions in
 _Sp_counted_base::_M_release when both counts are 1
To: Maged Michael <maged.michael@gmail.com>
Cc: "libstdc++" <libstdc++@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
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On Mon, 2 Aug 2021 at 14:29, Maged Michael wrote:
>
> This is the right patch. The previous one is missing noexcept. Sorry.
>
>
> On Mon, Aug 2, 2021 at 9:23 AM Maged Michael <maged.michael@gmail.com> wrote:
>>
>> Please find attached an updated patch after incorporating Jonathan's suggestions.
>>
>> Changes from the last patch include:
>> - Add a TSAN macro to bits/c++config.
>> - Use separate constexpr bool-s for the conditions for lock-freedom, double-width and alignment.
>> - Move the code in the optimized path to a separate function _M_release_double_width_cas.

Thanks for the updated patch. At a quick glance it looks great. I'll
apply it locally and test it tomorrow.