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Date: Tue, 15 Nov 2022 16:59:12 +0300 (MSK)
From: Alexander Monakov <amonakov@ispras.ru>
To: Jonathan Wakely <jwakely@redhat.com>
cc: Hongyu Wang <hongyu.wang@intel.com>, gcc-patches@gcc.gnu.org, 
    hongtao.liu@intel.com, ubizjak@gmail.com
Subject: Re: [PATCH] doc: Reword the description of -mrelax-cmpxchg-loop [PR
 107676]
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On Tue, 15 Nov 2022, Jonathan Wakely wrote:

> > How about the following:
> >
> > When emitting a compare-and-swap loop for @ref{__sync Builtins}
> > and @ref{__atomic Builtins} lacking a native instruction, optimize
> > for the highly contended case by issuing an atomic load before the
> > @code{CMPXCHG} instruction, and invoke the @code{PAUSE} instruction
> > when restarting the loop.
> 
> That's much better, thanks. My only remaining quibble would be that
> "invoking" an instruction seems only marginally better than running
> one. Emitting? Issuing? Using? Adding?

Right, it should be 'using'; let me also add 'to save CPU power':

When emitting a compare-and-swap loop for @ref{__sync Builtins}
and @ref{__atomic Builtins} lacking a native instruction, optimize
for the highly contended case by issuing an atomic load before the
@code{CMPXCHG} instruction, and using the @code{PAUSE} instruction
to save CPU power when restarting the loop.

Alexander