Article View: comp.arch
Article #20238Re: i860 overview (long)
From: William E. Davidsen Jr
Date: Thu, 09 Mar 1989 13:22
Date: Thu, 09 Mar 1989 13:22
29 lines
1901 bytes
1901 bytes
Several comments on my earlier posting:
(a) I was talking about the general case of machines which don't have
byte addressing and fetch a byte using a three step "load, shift, and"
and store a byte doing something like "load, and, shift, or, store". I
Didn't mean to imply that any particular RISC architecture used that
method. The Honeywell 6000 series was an example of not having direct
byte addressing (yes you can use a tally word but building it is as
slow as the and & ors). If the load and store time for an arbitrary
byte are the same as an alligned int, and if load/store byte is a
single operation, then I would consider it byte addressable for the
purposes of any program I want to run.
(b) several people posted results using big Sun4's and little Sun3's. I
believe that the tests were done on a Sun3/280 with FPU and a small Sun4
(I don't know the model number). Since troff is FP intensive (at least
on a VAX) that may be difference.
(c) the point I was trying to make was that a RISC processor which is "N
times faster" than some CISC processor is not going to have the same
improvement in all cases.
I'll post the actual results if I can get them from a rerun.
Boy are RISC people defensive!
--
bill davidsen (wedu@ge-crd.arpa)
{uunet | philabs}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me
Technical Details
Message-ID:
<13328@steinmetz.ge.com>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!ucsd!sdcsvax!ucsdhub!esosun!seismo!uunet!steinmetz!davidsenReferences:
<807@microsoft.UUCP> <92634@sun.uucp> <13322@steinmetz.ge.com> <1133@auspex.UUCP>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!ucsd!sdcsvax!ucsdhub!esosun!seismo!uunet!steinmetz!davidsen From: davidsen@steinmetz.ge.com (William E. Davidsen Jr) Newsgroups: comp.arch,comp.sys.intel Subject: Re: i860 overview (long) Message-ID: <13328@steinmetz.ge.com> Date: 9 Mar 89 13:22:34 GMT References: <807@microsoft.UUCP> <92634@sun.uucp> <13322@steinmetz.ge.com> <1133@auspex.UUCP> Reply-To: davidsen@crdos1.UUCP (bill davidsen) Organization: General Electric CRD, Schenectady, NY Lines: 29