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From: anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups: comp.arch
Subject: Re: is Vax addressing sane today
Date: Sat, 12 Oct 2024 08:23:39 GMT
Organization: Institut fuer Computersprachen, Technische Universitaet Wien
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Terje Mathisen <terje.mathisen@tmsw.no> writes:
>Maybe all add/sub/etc opcodes that are immediately followed by an INTO=20
>could be fused into a single ADDO/SUBO/etc version that takes zero extra =
>
>cycles as long as the trap part isn't hit?

On Intel P-cores add/inc/sub etc. has been fused with a following
JO/JNO into one uop for quite a while (I guess since Sandy Bridge
(2011)).

- anton
-- 
'Anyone trying for "industrial quality" ISA should avoid undefined behavior.'
  Mitch Alsup, <c17fcd89-f024-40e7-a594-88a85ac10d20o@googlegroups.com>