Beefy Boxes and Bandwidth Generously Provided by pair Networks
P is for Practical
 
PerlMonks  

Re^2: I prefer my indexes to start at:

by LanX (Saint)
on Sep 09, 2022 at 21:01 UTC ( [id://11146796]=note: print w/replies, xml ) Need Help??


in reply to Re: I prefer my indexes to start at:
in thread I prefer my indexes to start at:

AFAIR there always was a dedicated command for comparing with zero - for all flavors of "comparison" - because it's quite easy to implement and happens sufficiently often (e.g. when decrementing down).

And this command would also be shorter in length, since it doesn't need to read a constant from memory to compare with. And shorter length will also add up to the speed gain.

Now even if you used the longer command to compare with 0, a good assembler could try to optimize (think constant folding) a "comparison to a constant 0" to the shorter and faster "zero-compare"

I learned several assemblers, mainly MOS 6502 and Motorola 68000, but that was too long ago to tell you now where I've experienced this and give the correct mnemonics.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://11146796]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others cooling their heels in the Monastery: (4)
As of 2024-03-28 22:44 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found