Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!iuvax!uxc.cso.uiuc.edu!uxc.cso.uiuc.edu!mcdurb!aglew
From: aglew@mcdurb.Urbana.Gould.COM
Newsgroups: comp.arch
Subject: Re: SPARC Implementations
Message-ID: <28200336@mcdurb>
Date: 25 Jun 89 16:30:00 GMT
References: <351@ctycal.UUCP>
Lines: 23
Nf-ID: #R:ctycal.UUCP:351:mcdurb:28200336:000:928
Nf-From: mcdurb.Urbana.Gould.COM!aglew    Jun 25 11:30:00 1989


>>Can someone explain the basic differences between the Cypress and Fujitsu
>>SPARC implementations?  Are they binary code compatible?
>
>They are binary compatible, although the Cypress chip has a couple of
>instructions that the Fujitsu does not.

Terminology check - what does this mean?

Possibilities:

(1) the Cypress chip and the Fujitsu chip share all user mode instructions,
    but there are a few priviliged instructions that differ.

(2) the Cypress chip implements in hardware several instructions that are in
    the SPARC architecture definition, that the Fujitsu chip traps for, and
    for which a conforming implementation is required to provide emulation
    code.

(3) the extra instructions are accessible from user mode and not emulated,
    but are flagged "don't use these instructions if you want to be portable
    to other SPARCs". (I would sure hope that there's a compiler switch in this
    case).