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From: Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups: comp.arch
Subject: Re: Byte Addressability And Beyond
Date: Wed, 01 May 2024 12:08:32 -0400
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>> I guess the idea of  going all the way down to bit-level addressing
>>was considered a bit  extreme? 
>
> STRETCH had bit addressing. It added a great deal of complication for
> very little benefit. In the relatively rare situations where you want
> to handle bit fields, shifting and masking is good enough without
> slowing everything else down.

Bit addressing doesn't have to be expensive: the DEC Alpha could have
decided to use bit-addressing simply by ignoring/trapping more of the
lowest bits than it did.
Bit-addressing doesn't necessarily mean you can LD/ST at bit-granularity.


        Stefan