Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!usc!apple!mips!gumby!chan
From: chan@mips.COM (Sun C. Chan)
Newsgroups: comp.sys.mips
Subject: Re: as01.31 bug on the DecStation 3100
Message-ID: <33721@mips.mips.COM>
Date: 15 Dec 89 19:37:47 GMT
References: <HAM.89Dec14155738@Neon.Stanford.EDU>
Sender: news@mips.COM
Reply-To: chan@mips.COM (Sun C. Chan)
Distribution: comp
Organization: MIPS Computer Systems, Sunnyvale, CA
Lines: 24

In article <HAM.89Dec14155738@Neon.Stanford.EDU> ham@Neon.Stanford.EDU (Peter R. Ham) writes:
>as should restrict immediate constants to
>being within the range of -32768..32767.
>
>The 1.31 version of as0 fails to do this and lets some positive
>constants greater than 32767 slip by. Instead of complaining,
>as0 treats them as negative constants which can create bugs.
>Give the following assembly, as0 should complain about 5 of
>the lines, but instead only complains about 3. 32768 and
>40072 should be rejected. The results of assembling this
>are also included.
>
>
>addiu $0,$0, 32767
>addiu $0,$0, -32768
>addiu $0,$0, 32768
>addiu $0,$0, -32769
>addiu $0,$0, 40072
>addiu $0,$0, 0xfffffff
>addiu $0,$0, -0xffffff
>
This is indeed a bug in the as0, it has been fixed
and will be in the 2.10 release of the compiler.
Thanks for pointing this bug out.