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=0.2 required=5.0 tests=BAYES_00,INVALID_MSGID, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,251afb8f1c322bf0 X-Google-Attributes: gid103376,public From: dkristol@see-my.sig (David Kristola) Subject: Re: Memory mapped registers (was Re: Cachi Date: 1999/09/15 Message-ID: <7rn6js$3561@svlss.lmms.lmco.com>#1/1 X-Deja-AN: 525267234 Distribution: world References: <7rlc8g$cj8$1@nnrp1.deja.com> Organization: heaps of stacks Reply-To: dkristol@see-my.sig Newsgroups: comp.lang.ada Date: 1999-09-15T00:00:00+00:00 List-Id: In article 1@nnrp1.deja.com, Robert Dewar () writes: >Well it is not portable, more portable means that you may >get away with not having to rewrite it for a given port, >but the huge danger, as apparently in this case, is that The LWL/LWR & SWL/SWR problem was not a porting problem. That code was original, and now sits on a tar tape in a storage container locked in a room somewhere in building 151 (along with the hardware it ran on). The world is safe from that bit of code (the unchecked conversion to a 32 bit integer, the code that generated the LWL/LWR sequence was altered long ago). The LWL/LWR part worked. The SWL/SWR caused the hardware to place bad data in an unintended register. Even if the memory at the address functioned in a byte addressable way, memory outside the register would have been written. >the potential non-portability does not get flagged. By >using a machine code insertion, you definitely flag this >as something that needs looking at in a port. I shall use machine code insertions for this sort of implementation in the future. Thanks for pointing out the potential problems. Or, in other words: "Uncle!" ;-) --djk, keeper of arcane lore & trivial fluff Home: David95037 at aol dot com Spam: goto.hades@welovespam.com