From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: To: 9fans@9fans.net From: Richard Miller <9fans@hamnavoe.com> Date: Thu, 8 Oct 2009 11:44:42 +0100 In-Reply-To: <6c032f80acaccc9660f2d7b1e6cf71e7@9netics.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Subject: Re: [9fans] /sys/include/ip.h 5c(1) Topicbox-Message-UUID: 83d2d2bc-ead5-11e9-9d60-3106f5b1d025 >> microcode for the Perkin-Elmer 3220 was fun and useful as well. > > that's interesting. i found this paper and am studying it. are there > obvious advantages? I think there were quite a few independent projects at different places adding special-purpose instructions to accelerate particular algorithms. Improving on the original P-E (Interdata?) microcode wasn't hard. For example the base instruction set had instructions for inserting/deleting elements in a doubly-linked list, which were actually slower to execute than just doing the equivalent sequence of loads & stores.