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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.arch
Subject: Re: is Vax addressing sane today
Date: Sun, 22 Sep 2024 07:11:53 -0000 (UTC)
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On Sun, 22 Sep 2024 02:26:33 +0000, MitchAlsup1 wrote:

> It is faster if for no other reason that it did not fetch the branch
> that is always predicted non-taken.

But architectures like POWER were able to do that sort of thing in zero 
effective cycles, decades ago.

> If every calculation instruction had to be followed by a conditional
> branch, then the code would be 150% its original size (or worse).

Not every one. There are ways to do the checks only at crucial points, 
after sequences of instructions. This is how IEEE754 “exceptions” work, 
for example.