[PATCH v4 2/2] x86_64: roundeven with sse4.1 support

[H.J. Lu]

On Sun, May 31, 2020 at 6:28 PM Cui, Lili <lili.cui@intel.com> wrote:
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> From: H.J. Lu <hjl.tools@gmail.com>
> Sent: Friday, May 29, 2020 7:30 PM
> To: Cui, Lili <lili.cui@intel.com>
> Cc: Florian Weimer <fweimer@redhat.com>; H.J. Lu via Libc-alpha <libc-alpha@sourceware.org>; Shen-Ta Hsieh <ibmibmibm.tw@gmail.com>
> Subject: Re: [PATCH v4 2/2] x86_64: roundeven with sse4.1 support
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> On Fri, May 29, 2020 at 1:48 AM Cui, Lili <lili.cui@intel.com> wrote:
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> > -----Original Message-----
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> > From: H.J. Lu <hjl.tools@gmail.com>
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> > Sent: Thursday, May 28, 2020 8:32 PM
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> > To: Florian Weimer <fweimer@redhat.com>; Cui, Lili <lili.cui@intel.com>
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> > Cc: H.J. Lu via Libc-alpha <libc-alpha@sourceware.org>; Shen-Ta Hsieh
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> > <ibmibmibm.tw@gmail.com>
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> > Subject: Re: [PATCH v4 2/2] x86_64: roundeven with sse4.1 support
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> >
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> > On Thu, May 28, 2020 at 5:22 AM Florian Weimer <fweimer@redhat.com>
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> > wrote:
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> > > * H. J. Lu via Libc-alpha:
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> > > >> Here is a benchmark result on my AMD Ryzen 9 3900X system:
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> > > > Since we don't know or may not care SSE4 machines without AVX,
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> > > > should we make it to AVX only?
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> > > What about Goldmont/Tremont?  Those are current CPUs which do not
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> > > support AVX, but I think they have sufficient SSE4 support levels for
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> > > this change.
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> > Good point.  Lili, please collect glibc micro benchmark roundeven/roundevenf
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> > data before and after:
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> > https://sourceware.org/pipermail/libc-alpha/2020-May/113533.html
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> >
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> > on Tremont.
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> > --
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> > H.J.
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> Hi H.J,
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> Result is here.
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> benchmark result before this commit on Tremont
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> benchmark result after this commit on Tremont
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> Hi Lili,
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> The results are empty.
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> --
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> H.J.
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> Hi H.J,
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> Sorry for that my format has some problems, data is here.
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> benchmark result before this commit on Tremont
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>    "roundeven":                                        "roundevenf":
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>     "duration": 2.19422e+09,                    "duration": 2.19402e+09,
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>     "iterations": 1.44514e+08,                  "iterations": 1.4184e+08,
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>     "max": 43.258,                                       "max": 53.07,
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>     "min": 11.052,                                        "min": 12.052,
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>     "mean": 15.1835                                    "mean": 15.4683
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> benchmark result after this commit on Tremont
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>      "roundeven":                                   "roundevenf":
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>      "duration": 2.19144e+09,             "duration": 2.19218e+09,
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>      "iterations": 2.17075e+08,           "iterations": 1.97982e+08,
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>      "max": 395.428,                             "max": 34.928,
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>      "min": 10.044,                                "min": 11.02,
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>      "mean": 10.0953                           "mean": 11.0726
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Looks good.

Thanks.

-- 
H.J.