Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Stefan Monnier Newsgroups: comp.arch Subject: Re: Memory ordering Date: Tue, 03 Dec 2024 18:37:41 -0500 Organization: A noiseless patient Spider Lines: 19 Message-ID: References: <-rKdnTO4LdoWXKj6nZ2dnZfqnPWdnZ2d@supernews.com> <5yqdnU9eL_Y_GKv6nZ2dnZfqn_GdnZ2d@supernews.com> <2024Nov15.082512@mips.complang.tuwien.ac.at> <20241115152459.00004c86@yahoo.com> <2024Nov17.161752@mips.complang.tuwien.ac.at> <2024Dec3.100144@mips.complang.tuwien.ac.at> <3aa9f0a3d3dde86193abb1c01e52d03a@www.novabbs.org> MIME-Version: 1.0 Content-Type: text/plain Injection-Date: Wed, 04 Dec 2024 00:37:42 +0100 (CET) Injection-Info: dont-email.me; posting-host="c66a6dbeddf801ae87a9f94174194f38"; logging-data="454688"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18jtin+IHYBRt8eXrYREh9N8NYykzZHXX4=" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:cOXgE12H5u/a3nEmhM7D06krs4I= sha1:+fS5HrwcvlfiUfZNT0USloNtqIs= Bytes: 2064 >> If there are places >> in the code it doesn't know this can't happen it won't optimize >> across it, more or less. > > The problem is HOW to TELL the COMPILER that these memory references > are "more special" than normal--when languages give few mechanisms. We could start with something like critical_region { ... } such that the compiler must refrain from any code motion within those sections but is free to move things outside of those sections as if execution was singlethreaded. Stefan