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Re: Static_assert in 2017 C++

From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.lang.c++
Subject Re: Static_assert in 2017 C++
Date 2019-09-01 22:39 -0700
Organization Aioe.org NNTP Server
Message-ID <qki9tr$7pp$1@gioia.aioe.org> (permalink)
References (2 earlier) <0vjnmed6aagu8qkvqiomsnces4kdqtb1oh@4ax.com> <qki2lv$1afq$1@gioia.aioe.org> <ao3pme5rq2d8te39ae75btekd302htqn70@4ax.com> <qki4qo$1ien$1@gioia.aioe.org> <m58pmedspif170p18c1ebih27gh09ea1od@4ax.com>

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On 9/1/2019 10:09 PM, Robert Wessel wrote:
> On Sun, 1 Sep 2019 21:12:08 -0700, "Chris M. Thomasson"
> <chris.m.thomasson.1@gmail.com> wrote:
> 
>> On 9/1/2019 8:50 PM, Robert Wessel wrote:
>>> On Sun, 1 Sep 2019 20:35:27 -0700, "Chris M. Thomasson"
>>> <chris.m.thomasson.1@gmail.com> wrote:
>>>
>>>> On 9/1/2019 7:21 AM, Robert Wessel wrote:
>>>>> On Sun, 1 Sep 2019 12:48:07 +0200, Bonita Montero
>>>>> <Bonita.Montero@gmail.com> wrote:
>>>>>
>>>>>>> I have this line
>>>>>>> static_assert(::std::numeric_limits<float>::is_iec559,"Only IEEE754 supported");
>>>>>>
>>>>>> That's not necessary because no one will write a C++17-conformant
>>>>>> compiler for an ancient architecture without IEEE-754-floating-points
>>>>>> and is realistic to expect that there will be never any future CPU
>>>>>> that implements floats differently.
>>>>>> Its just one of those compulsive nerd-assessments.
>>>>>
>>>>>
>>>>> While IBM has not yet released a C++17 version of XL C/C++ for z/OS,
>>>>> they are widely expected to, and for it, like the C++11 version, to
>>>>> support both IEEE and IBM S/360 hex style floats via a compiler
>>>>> option.  In any event, numeric_limits::is_iec559 is C++11, and
>>>>> supported on that compiler as you expect for both hex and binary FP.
>>>>>
>>>>
>>>> I want to see the DWCAS impl for z/OS. It should be able to handle the
>>>> normal lock-free lifo:
>>>>
>>>> Appendix 48 : A-48 in, Free Pool Manipulation:
>>>>
>>>> https://www-01.ibm.com/support/docview.wss?aid=1&uid=isg26480faec85f44e2385256d5200627dee
>>>
>>>
>>> You need to find a newer PoOp.  That one is 15 years out of date.
>>> Search for "SA22-7832-11".
>>>
>>> I'm also not quite sure what you're asking.  The ISA implements CAS
>>> and DWCAS (CSxx and CDxx instructions) as well as some other
>>> compare-and-swap variations in both 32 and 64-bit sizes.  A number of
>>> additional atomic operations exist under the Perform Locked Operation
>>> instruction.
>>>
>>
>> Right. So C++11 on the zArch can support 64-bit double width
>> compare-and-swap atomics with 32 bit words. And 128 DWCAS with 64 bit
>> words, right?
> 
> 
> Yes.  CDSG does a compare and swap on a 128-bit value stored in a pair
> of (64-bit) registers with a quadword in memory.
> 
> Compare and Swap and Store is something of enhancement, and allows for
> the miscompared value to update another structure in the same atomic
> operation.
> 
> Perform Locked Operation can do a variety of atomic operation
> including DCAS, and CAS with multiple updates.
> 

Ohhh, yeah. The PLO instruction is very interesting indeed!

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Static_assert in 2017 C++ woodbrian77@gmail.com - 2019-08-31 15:55 -0700
  Re: Static_assert in 2017 C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-09-01 11:43 +0100
    Re: Static_assert in 2017 C++ rick.c.hodgin@gmail.com - 2019-09-01 04:16 -0700
      Re: Static_assert in 2017 C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-09-01 13:15 +0100
    Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-01 14:56 +0200
      Re: Static_assert in 2017 C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-09-01 14:20 +0100
        Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-01 15:35 +0200
          Re: Static_assert in 2017 C++ Ian Collins <ian-news@hotmail.com> - 2019-09-02 07:30 +1200
            Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 07:16 +0200
              Re: Static_assert in 2017 C++ David Brown <david.brown@hesbynett.no> - 2019-09-02 13:13 +0200
                Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 15:55 +0200
                Re: Static_assert in 2017 C++ David Brown <david.brown@hesbynett.no> - 2019-09-02 22:02 +0200
  Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-01 12:48 +0200
    Re: Static_assert in 2017 C++ Robert Wessel <robertwessel2@yahoo.com> - 2019-09-01 09:21 -0500
      Re: Static_assert in 2017 C++ woodbrian77@gmail.com - 2019-09-01 09:53 -0700
        Re: Static_assert in 2017 C++ Robert Wessel <robertwessel2@yahoo.com> - 2019-09-01 22:29 -0500
          Re: Static_assert in 2017 C++ Robert Wessel <robertwessel2@yahoo.com> - 2019-09-01 22:34 -0500
            Re: Static_assert in 2017 C++ woodbrian77@gmail.com - 2019-09-02 07:32 -0700
      Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 20:35 -0700
        Re: Static_assert in 2017 C++ Robert Wessel <robertwessel2@yahoo.com> - 2019-09-01 22:50 -0500
          Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 21:12 -0700
            Re: Static_assert in 2017 C++ Robert Wessel <robertwessel2@yahoo.com> - 2019-09-02 00:09 -0500
              Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 22:39 -0700
              Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-04 22:49 -0700
          Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 21:13 -0700
            Re: Static_assert in 2017 C++ Robert Wessel <robertwessel2@yahoo.com> - 2019-09-02 00:20 -0500
              Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 22:41 -0700
        Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 07:14 +0200
          Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 22:46 -0700
            Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 07:55 +0200
              Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 22:58 -0700
                Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 08:20 +0200
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 23:24 -0700
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 23:25 -0700
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 23:26 -0700
                Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 08:33 +0200
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-02 00:18 -0700
                Re: Static_assert in 2017 C++ Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-02 09:23 +0200
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-02 00:26 -0700
              Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 22:58 -0700
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-01 22:59 -0700
                Re: Static_assert in 2017 C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-09-04 23:04 -0700
  Re: Static_assert in 2017 C++ Richard Damon <Richard@Damon-Family.org> - 2019-09-01 15:39 -0400
    Re: Static_assert in 2017 C++ woodbrian77@gmail.com - 2019-09-01 18:58 -0700
      Re: Static_assert in 2017 C++ Richard Damon <Richard@Damon-Family.org> - 2019-09-02 17:40 -0400
        Re: Static_assert in 2017 C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-02 22:53 -0400
        Re: Static_assert in 2017 C++ David Brown <david.brown@hesbynett.no> - 2019-09-03 08:21 +0200
    Re: Static_assert in 2017 C++ Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-09-02 14:43 +0000
  Re: Static_assert in 2017 C++ Keith Thompson <kst-u@mib.org> - 2019-09-01 20:48 -0700
  Re: Static_assert in 2017 C++ David Brown <david.brown@hesbynett.no> - 2019-09-03 08:25 +0200
    Re: Static_assert in 2017 C++ Keith Thompson <kst-u@mib.org> - 2019-09-03 00:35 -0700
      Re: Static_assert in 2017 C++ David Brown <david.brown@hesbynett.no> - 2019-09-03 10:31 +0200

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