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From: Thomas Koenig <tkoenig@netcologne.de>
Newsgroups: comp.arch
Subject: Re: Segments
Date: Tue, 7 Jan 2025 11:05:20 -0000 (UTC)
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Scott Lurndal <scott@slp53.sl.home> schrieb:

>>Assume a class of load and store instructions containing
>>
>>- One source or destination register
>>- One base register
>>- One index register
>>- One ubound register
>
> See aforementioned CHERI.

CHERY targets C, which on the one hand, I understand (there's a
ton of C code out there), but trying to retrofit a safe memory
model onto C seems a bit awkward - it might have been better to
target a language which has arrays in the first place, unlike C.

The floating point size is weird (and also does not catch all
errors, such as writing one element past a huge array).

I haven't seen any consideration of how CHERI would integrate
with languages which have multidimensional arrays.  How would

  do j=1,10
    do i=1,11
      a(i,j) = 42.
    end do
  end do

interact with Cheri if a was a 10*10 array ?  Would it be
necessary to create a capability for a(:,j)?