Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!decwrl!decvax!mcnc!thorin!unc!ohbuchi
From: ohbuchi@unc.cs.unc.edu (Ryutarou Ohbuchi)
Newsgroups: comp.arch
Subject: Re: 16 & 32 bit vs 32 bit only instructions for RISC.
Message-ID: <1460@thorin.cs.unc.edu>
Date: 28 Feb 88 17:04:08 GMT
References: <9651@steinmetz.steinmetz.UUCP> <9678@steinmetz.steinmetz.UUCP> <2574@im4u.UUCP> <2116@saturn.ucsc.edu> <1697@winchester.mips.COM>
Sender: news@thorin.cs.unc.edu
Reply-To: ohbuchi@unc.UUCP (Ryutarou Ohbuchi)
Organization: University Of North Carolina, Chapel Hill
Lines: 35

In article <2116@saturn.ucsc.edu> haynes@ucscc.UCSC.EDU (Jim Haynes) writes:
>In article <2574@im4u.UUCP> rajiv@im4u.UUCP (Rajiv N. Patel) writes:
>I'm glad somebody brought this up, and while we're also at it let's debate
>the value of including 16 bit data types in RISC machines.  A variety
>of data sizes slows a machine down almost as much as a variety of
>instruction sizes.  I was rather surprised to see that Sun included
>16-bit data in SPARC in this day and age of cheap memory.  8-bit data
>has the obvious utility for character strings; but do we really need
>16-bit integers anymore?

To us Japanese, 16bit unsigned integer too has the obvious utility for 
character strings.  We use 16bit/char. code for Kanji+Kanas+Alpha-numeric
characters.  

There are few variations to encode Kanji (unbounded, but about 7k-8k for
business use), Kanas (2 different sets of abuot 60 each), and alphanumerics
intermixed. Scanning these 8bit (ASCII)/ 16bit (JIS; Japanese Industry 
Standard) mixed string is a pain (simple FSM, sometime).  You need a new
set of C string libraries. Also in these code, bit7 (8'th bit) is used, 
which is messy with some UNIX utilities.  Want to try Boyer-Moore string
matching with alphabet size of 10K ?  It will be an interesting excersize.  

Chinese, and several other languages need larger character set, too.  
If you want to export computers and operating systems to these countries, 
you better not forget (Along with I/O devices, of course. Who buy a 
business computer which print bills in unreadable characters ?)

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Any opinion expressed here is my own.
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Ryutarou Ohbuchi	"Life's rock."   "Climb now, work later." and, now,
			"Life's snow."   "Ski now, work later."
ohbuchi@cs.unc.edu	<on csnet>
Department of Computer Science, University of North Carolina at Chapel Hill
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