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From: Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups: comp.arch
Subject: Re: Keeping other stuff with addresses
Date: Tue, 03 Dec 2024 13:46:01 -0500
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>>> another way to steal bits is over alignment.
>>Yup.  I keep lamenting that Alpha didn't go for bit-addressed memory,
>>which would have given us 3 extra free bits from alignment (as well as
>>allowing pointers to bits and bitfields).
> I thought STRETCH persuaded people that bit addressable memory was a bad idea.

Yes, but that was a misunderstanding.  I'm not suggesting that
load/store instructions can access things at any bit position and any
bit size.  Any load or store with a pointer whose last 3 bits is not 0 would
presumably signal en error.
Just like the 21064 Alpha where they had byte-addressed memory but the
load/store instructions could only handle aligned words.


        Stefan