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Re: DCAS-supplement ?

From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.lang.c++
Subject Re: DCAS-supplement ?
Date 2021-09-19 22:19 -0700
Organization Aioe.org NNTP Server
Message-ID <si95lr$1lsg$1@gioia.aioe.org> (permalink)
References <si7njq$udv$1@dont-email.me> <si8dkm$6cv$1@gioia.aioe.org> <si94nf$vf0$1@dont-email.me>

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On 9/19/2021 10:03 PM, Bonita Montero wrote:
> Am 20.09.2021 um 00:29 schrieb Chris M. Thomasson:
>> On 9/19/2021 9:13 AM, Bonita Montero wrote:
>>> I just wanted to test if my compiler recognizes ...
>>>      atomic<pair<uintptr_t, uintptr_t>
>>> ... and uses DCASes on it or if it supplements the pair with a usual
>>> lock. 
>>
>> [...]
>>
>> Can you get this to compile on your MSVC?
>> _________________________
>> #include <iostream>
>> #include <atomic>
>> #include <xmmintrin.h>
>>
>> int main()
>> {
>>      std::atomic<__int64> foo_64;
>>      std::atomic<__m128> foo_128;
>>
>>      std::cout << sizeof(__int64) << "\n";
>>      std::cout << sizeof(__m128) << "\n";
>>
>>      std::cout << foo_64.is_lock_free() << "\n";
>>      std::cout << foo_128.is_lock_free() << "\n";
>>
>>      return 0;
>> }
>> _________________________
>>
> 
> That's not what I wanted to test.
> Read this thread:
> 
> https://stackoverflow.com/questions/69245183/dcas-alternative-with-no-help-of-the-kernel 
> 

A quote:

"I just wanted to test if my compiler recognizes ...and uses DCASes on 
it or if it supplements the pair with a usual lock"

Well, is_lock_free() should help?

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Thread

DCAS-supplement ? Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-19 18:13 +0200
  Re: DCAS-supplement ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-19 15:29 -0700
    Re: DCAS-supplement ? Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-20 07:03 +0200
      Re: DCAS-supplement ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-19 22:19 -0700
        Re: DCAS-supplement ? Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-20 07:26 +0200
          Re: DCAS-supplement ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-19 22:40 -0700
          Re: DCAS-supplement ? Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-20 07:53 +0200
            Re: DCAS-supplement ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-20 16:02 -0700
              Re: DCAS-supplement ? Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-21 09:31 +0200
                Re: DCAS-supplement ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-21 16:09 -0700

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