Path: ...!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail
From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: Banked register files
Date: Tue, 27 Aug 2024 00:32:50 +0000
Organization: Rocksolid Light
Message-ID: <95b2ce27c781e0556864a8b7d4b55187@www.novabbs.org>
References: <va0eev$31fml$1@dont-email.me> <484586d667d1e9e7ae11184dbd362619@www.novabbs.org> <va0k4v$32dgq$1@dont-email.me> <2cf5a18a58a4281b1b67935b31a8fe49@www.novabbs.org> <va1412$3881u$1@dont-email.me> <va8c9j$j6q1$1@dont-email.me> <vabto4$19iip$1@dont-email.me> <vad56j$1fm8b$1@dont-email.me> <vair0o$2k32g$1@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Info: i2pn2.org;
	logging-data="4033741"; mail-complaints-to="usenet@i2pn2.org";
	posting-account="65wTazMNTleAJDh/pRqmKE7ADni/0wesT78+pyiDW8A";
User-Agent: Rocksolid Light
X-Rslight-Site: $2y$10$WJbMv05EsrL5s2WtYAXfv.Pb36kCe/.YLwtdsPmE7/9IEWMbiBs0q
X-Spam-Checker-Version: SpamAssassin 4.0.0
X-Rslight-Posting-User: ac58ceb75ea22753186dae54d967fed894c3dce8
Bytes: 2412
Lines: 32

On Mon, 26 Aug 2024 21:10:48 +0000, Brett wrote:

> Brett <ggtgp@yahoo.com> wrote:
>> Robert Finch <robfi680@gmail.com> wrote:
>>> On 2024-08-22 5:58 p.m., Brett wrote:
>>>> Brett <ggtgp@yahoo.com> wrote:
>>>>> MitchAlsup1 <mitchalsup@aol.com> wrote:
>>>
>>> I saw a design where there was an attempt to process basic blocks in
>>> parallel silos feeding functional units. It made use of fewer registers
>>> by holding data in pipeline registers instead of GPRs which it could do
>>> since some of the data for a basic block never goes outside the block.
>
> No reply’s, so I figure y’all are under NDA. ;)

It has been well known since mid 1990s that most loops end up with a
single
or dual stream of self dependent instructions and few loop dependencies
{mostly the loop index itself}. This leads to instruction dependency
graphs (and execution times) that look like::

     | LD  |
     | LD  |
           |    FMUL    |
                        |    FADD    |
     | STA |                         | STD |
     | ADD |
           | CMP |
                 | BV  |
------------------------------------------------------------
           | LD  |
           | LD  |
                 |    FMUL   |