Re: Keeping other stuff with addresses

According to Stefan Monnier  <monnier@iro.umontreal.ca>:

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.
Some of the 1970s Burroughs machines were bit addressable at the microcode level
but I think they just used it to do different word sizes for different application
microcode.

The word=addressed PDP-6/10 could address bit fields just fine using byte
pointers that had address, offset, and size fields. It had load and store byte,
load and store after incrementing the pointer to the next byte, and on later
models, advance the pointer by N bytes. It was nice but 95% of the time they
were used in a single way to pack and unpack 7 bit ASCII characters in 36 bit
words.

R's,
John
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