Re: is Vax addressing sane today

On Sun, 22 Sep 2024 01:23:35 +0000, MitchAlsup1 wrote:

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.

It occupies some space, either microcode or circuit logic, or both.

And why should that be faster?