Path: ...!news.misty.com!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: mitchalsup@aol.com (MitchAlsup1) Newsgroups: comp.arch Subject: Re: First-Part-Done (was Re: Byte Addressability And Beyond) Date: Mon, 3 Jun 2024 16:36:37 +0000 Organization: Rocksolid Light Message-ID: References: <7yn5O.33584$9xU7.29321@fx17.iad> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Info: i2pn2.org; logging-data="3086945"; mail-complaints-to="usenet@i2pn2.org"; posting-account="65wTazMNTleAJDh/pRqmKE7ADni/0wesT78+pyiDW8A"; User-Agent: Rocksolid Light X-Rslight-Posting-User: ac58ceb75ea22753186dae54d967fed894c3dce8 X-Rslight-Site: $2y$10$d4lck9wwO1N/oKoGsTYRQuZe6oCoDuz.dxIWaZXSFVpYSLljQKC9m X-Spam-Checker-Version: SpamAssassin 4.0.0 Bytes: 1912 Lines: 19 Scott Lurndal wrote: > Lawrence D'Oliveiro writes: >>On Thu, 30 May 2024 14:42:14 -0000 (UTC), John Levine wrote: >> >>> The condition code tells you which it was. If it was an interrupt, you >>> just branch back and keep going. >> >>Does it really hurt performance for the CPU to keep track of the fact >> that >>an instruction has to be restarted after an interrupt? It is already a requirement that we have precise interrupts. Those Rqs impose that the unfinished instruction is pointed at by IP on return. > Yes, of course. And it complicates the design, which makes it harder > to verify, particularly for an out-of-order design. If you can backup mispredicted branches, you have all the OoO HW to restart a long running instruction.