Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: John Savard Newsgroups: comp.arch Subject: Re: Privilege Levels Below User Date: Sun, 09 Jun 2024 09:14:11 -0600 Organization: A noiseless patient Spider Lines: 25 Message-ID: <4fhb6jdpr1tlonfum9cccq9j1h2vrlo60j@4ax.com> References: <2ad84effd7f284445e0d8b90e0170f09@www.novabbs.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Injection-Date: Sun, 09 Jun 2024 17:14:11 +0200 (CEST) Injection-Info: dont-email.me; posting-host="f3b069b4ba52a43e376440ac19ed976b"; logging-data="3777411"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/AlLkQjdCOio4cGz5zH+RGAGjei5XGNpE=" Cancel-Lock: sha1:EMmfv59ZrUcMWjWY0L4X0t4m4ho= X-Newsreader: Forte Free Agent 3.3/32.846 Bytes: 1934 On Fri, 7 Jun 2024 20:40:34 +0000, mitchalsup@aol.com (MitchAlsup1) wrote: >Are Supervisor Calls "brnches" since they go to controlled entry >points?? Well, they're a kind of subroutine call. But they're really instructions that initiate the computer's response to an interrupt, which is what makes the entry point controlled and the instruction able to increase privilege. >How are you going to perform elementary functions {SIN, COS, EXP, LOG}? Just because the feature exists doesn't mean it needs to be used for everything. Ordinary subroutine calls will still exist, so if these routines require scratchpad memory, that will be fine. >A C compiler is an application running in a different process. Why >is a JIT "not like that" ?? A C compiler doesn't save data in memory that can then be executed. It writes to a file. The linking loader, instead, is "like" a JIT compiler in that respect. John Savard