8:58 from the fogs of 68k assembly programming on the Amiga: it was a (sort of?) rule that the callee had to save the registers it used (except for those considered "scratch registers"), so that every subroutine usually started with movem.l d2-d7/a2-a6, -(sp) and ended with movem.l (sp)+, d2-d7/a2-a6 just before the rts (return instruction - 68k "branch/jump to subroutine" pushes the return address on the stack - pointed by a7, alias sp just to make it clear we are dealing with the stack). And if you, as the writer of the subroutine, knew that you were not going to overwrite any register (beyond d0-d1 and a0-a1), you could spare the movem instruction. I think I prefer a calling convention that forces this guarantees making the callee take care of not overwriting certain registers, rather than making the caller always worry about it.
Interesting to see how things have changed since the Archimedes/Risc PC era (Arm 2/3). I have MOV PC,R14 etched into my brain for returning from a function call 😁
Great explanation. I didn't find any gaps. Brilliant! Thank you! 👏👏👏🙏
Thanks for all your effort! Great content!
Such a great video! Keep it up :)
I like watching your channel so I practice my English listening and learn more about ARM as well
great videos. thanks!
8:58 from the fogs of 68k assembly programming on the Amiga: it was a (sort of?) rule that the callee had to save the registers it used (except for those considered "scratch registers"), so that every subroutine usually started with movem.l d2-d7/a2-a6, -(sp) and ended with movem.l (sp)+, d2-d7/a2-a6 just before the rts (return instruction - 68k "branch/jump to subroutine" pushes the return address on the stack - pointed by a7, alias sp just to make it clear we are dealing with the stack). And if you, as the writer of the subroutine, knew that you were not going to overwrite any register (beyond d0-d1 and a0-a1), you could spare the movem instruction. I think I prefer a calling convention that forces this guarantees making the callee take care of not overwriting certain registers, rather than making the caller always worry about it.
Interesting to see how things have changed since the Archimedes/Risc PC era (Arm 2/3).
I have MOV PC,R14 etched into my brain for returning from a function call 😁
thanks for this amazing content
Great series
arent you a bit too old to be watching this?
The sickest of intros.
Thanks!
how was this intro made? its amazing
U are the one.
7:30 the vietnam flashback took me off guard
What is I flag in cpsr?🤔
Something about the frequency of your voice tickles my ears 😂👂
Present day, present time Hahahaha
i saw u on linkedin and your content seems amazing too. hoping to learn from you. also that lain reference is epic ;)