My new favourite AArch64 CPU instruction: RMIF – rotate then merge in to flags

corsix.org

5 pointsingve6 comments

I tried to find that list of fake funny assembly instructions last night and couldn't for the life of me. This reminded me of it. If anyone else loves funny assembly things, please save me.

Not sure if this is it

https://web.archive.org/web/20170908154113/https://www.physi...

yes, thank you. Looks like it was taken down which would explain why I couldn't google for it. I was looking for the COMF instruction.

Who need fake funny assembly instructions when PowerPC has real funny assembly instructions like EIEIO - Enforce In-Order Execution of I/O? [0]

[0] https://www.ibm.com/docs/en/aix/7.3?topic=set-eieio-enforce-...

While we are on funny real instructions, I remember years ago thinking that the VAX MOVTUC instruction was the hilarious pinnacle of CISC instructions

http://odl.sysworks.biz/disk$axpdocdec011/opsys/vmsos73/vmso...

I think there are basically single instruction strlen in an x86 extension now? This is why people say that even assembly isn't the lowest level. Who knows how many uOPs these things are. Not sure of VAX architecture if there even are uOPs, but on a modern CPU, it's crazy how abstracted everything is.

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