Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.arch > #1515

Re: Anyone take a serious look at partitioned register sets?

Path csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!selfless.tophat.at!news.glorb.com!border3.nntp.dca.giganews.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!news.giganews.com.POSTED!not-for-mail
NNTP-Posting-Date Thu, 12 May 2011 21:26:38 -0500
Message-ID <4DCC96D2.40603@SPAM.comp-arch.net> (permalink)
Date Thu, 12 May 2011 19:26:26 -0700
From "Andy \"Krazy\" Glew" <andy@SPAM.comp-arch.net>
Reply-To andy@SPAM.comp-arch.net
Organization comp-arch.net
User-Agent Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2.11) Gecko/20101013 Thunderbird/3.1.5
MIME-Version 1.0
Newsgroups comp.arch
Subject Re: Anyone take a serious look at partitioned register sets?
References <670793a0-7d16-4163-b717-e0d53dc82d54@glegroupsg2000goo.googlegroups.com>
In-Reply-To <670793a0-7d16-4163-b717-e0d53dc82d54@glegroupsg2000goo.googlegroups.com>
Content-Type text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding 7bit
Lines 31
X-Usenet-Provider http://www.giganews.com
X-Trace sv3-G7a+2TnjWi+D/QYgiyhMriKNB/3vWwDyM9nZydHtGn8T12DSfIQYdBlEOC8ePy+GtAv44STI1PKNl3O!lCB5nhtvCdT9yddJ9vDudoYm0kuB+Nt4w4HjHDTCK/iRrS/dTiRwfn/L0P3FJA==
X-Complaints-To abuse@giganews.com
X-DMCA-Notifications http://www.giganews.com/info/dmca.html
X-Abuse-and-DMCA-Info Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info Otherwise we will be unable to process your complaint properly
X-Postfilter 1.3.40
X-Original-Bytes 2709
Xref x330-a1.tempe.blueboxinc.net comp.arch:1515

Show key headers only | View raw


On 5/12/2011 8:26 AM, Paul A. Clayton wrote:
> On Thursday, May 12, 2011 3:43:34 AM UTC-4, Michael S wrote:
> [snip]
>> Sounds like you are talking about different things. Or, may be, you
>> and Paul are talking about the same thing, but Brett was talking about
>> something else.
>> Duplicated integer register file in Ev6/Ev7 is just an implementation
>> detail. Brett, on the other hand, was arguing in favor of software-
>> visible partitioning, similar to TI C6000 family, but more far-
>> fetched.
>
> I think Brett is looking at microarchitecture splitting as
> an indication of the appropriateness of Architectural
> splitting.  I.e., if EV6-style clustering is so useful,
> why not Architect the split and avoid some of the
> overhead.

The answer is: compatibility. Lifetime of the architecture.

If your architecture is going to last many years, it may be built on 
many different microarchitectures.  Some of which have split RF, some 
which don't.

If your architecture is likely to only ever be used in 
microarchitectures that benefit from split RF, expose it.

By the way, the TI DSP architecture has lasted a long time.  For many 
years the DSP architectures were characterized by split X/Y registers.

(By the way, I think the meaningful split noawadays is not integer 
versus FP, but scalar (64b) versus SIMD packed vector (128-256-512 bit).)

Back to comp.arch | Previous | Next — Previous in thread | Find similar | Unroll thread


Thread

Re: Anyone take a serious look at partitioned register sets? "Paul A. Clayton" <paaronclayton@gmail.com> - 2011-05-12 08:26 -0700
  Re: Anyone take a serious look at partitioned register sets? "Andy \"Krazy\" Glew" <andy@SPAM.comp-arch.net> - 2011-05-12 19:26 -0700

csiph-web