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From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: is Vax addressing sane today
Date: Sun, 22 Sep 2024 01:23:35 +0000
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On Sat, 21 Sep 2024 23:29:01 +0000, Lawrence D'Oliveiro wrote:

> On Sat, 21 Sep 2024 20:39:38 +0000, MitchAlsup1 wrote:
>
>> In the days before <good> branch prediction having a conditional branch
>> after each instruction that could have an execution problem was an
>> extremely poor choice. Thus, exceptions were invented (circa 1958).
>
> So all that does is push the conditional branch into the microcode. And
> make the instruction more complicated. Why should that be faster?

It pushes the branch into the mispredict-recovery path and does not
occupy any code space.

There is no microcode outside of Z-system these days.