From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,3ccb707f4c91a5f2 X-Google-Attributes: gid103376,public From: kilgallen@eisner.decus.org (Larry Kilgallen) Subject: Re: Fast locking (Was Re: Java vs Ada 95) Date: 1996/11/06 Message-ID: <1996Nov5.235745.1@eisner>#1/1 X-Deja-AN: 194791334 x-nntp-posting-host: eisner.decus.org references: <325BC3B3.41C6@hso.link.com> <55gkch$gg6@fozzie.sun3.iaf.nl> <55o4g4$ki8@fozzie.sun3.iaf.nl> x-nntp-posting-user: KILGALLEN x-trace: 847256285/12200 organization: LJK Software newsgroups: comp.lang.ada Date: 1996-11-06T00:00:00+00:00 List-Id: In article <55o4g4$ki8@fozzie.sun3.iaf.nl>, geert@fozzie.sun3.iaf.nl (Geert Bosch) writes: > This means that test-and-set is not possible using just GNAT at the > moment and indeed implementing efficient spin-locks is not possible. > Hopefully the extra intrinsic subprograms will be implemented > sometime. Descriptions of the GNAT developer environment posted here have emphasized uniformity across platforms indicating that many of those depending on it required that uniformity. My presumption is that those folks have portable Ada code in mind. The machine semantics of test-and-set on whatever machine you are describing would seem to be somewhat different from the Alpha AXP load-locked/store-conditional semantics. A higher level construct which supports portable programs seems better to me than something specific to test-and-set hardware semantics. (When I wrote about spin locks earlier in this thread, I thought we were discussing techniques for compiler writers to use rather than something exposed to Ada programmers.) Larry Kilgallen