Article View: comp.arch
Article #12721Re: Speed is the one true performance metric
From: Henry Spencer
Date: Mon, 17 Nov 1986 18:13
Date: Mon, 17 Nov 1986 18:13
17 lines
1420 bytes
1420 bytes
> CORRELARY: I bet the same thing happens soon (if it hasn't already) inside
> somebody's fancy new CPU chips...
Arguably it has. For quite a while the 32032 had an obscure (although
documented) bug reminiscent of your examples. If I recall correctly, the
problem was that if a lot of the high bits in the stack pointer were 1s,
and an increment caused a carry to go up all the way and turn a lot of
those bits to 0s all at once, the increment gave the wrong result. My
guess would be that the pattern-sensitivity indicates an analog electrical
problem rather than a logic error.
(I can't be sure I've got the details right, since I threw out my 32032
bug lists when I finally concluded that I was never going to use the chip
and didn't care about it any more, but it was something along those lines.)
--
Henry Spencer @ U of Toronto Zoology
{allegra,ihnp4,decvax,pyramid}!utzoo!henry
Technical Details
Message-ID:
<7326@utzoo.UUCP>Path:
arc1-ca.pugleaf.net!utzoo!henryReferences:
<340@euroies.UUCP>Show Full Headers
Complete Article Headers
Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!henry From: henry@utzoo.UUCP (Henry Spencer) Newsgroups: comp.arch Subject: Re: Speed is the one true performance metric Message-ID: <7326@utzoo.UUCP> Date: Mon, 17-Nov-86 13:13:08 EST Article-I.D.: utzoo.7326 Posted: Mon Nov 17 13:13:08 1986 Date-Received: Mon, 17-Nov-86 13:13:08 EST References: <340@euroies.UUCP> Organization: U of Toronto Zoology Lines: 17