Comment 2RYE Re: How does this compare to 32bit?


Intro to x86 64 bit programming


How does this compare to 32bit? (Score: 2, Interesting)

by on 2014-09-01 02:11 (#2RYD)

I would like to see side-by-side comparison with 32-bit version of the same program.
I am very rusty in assembly but I doubt it would look much different apart from the register names.
(64-bit uses prefix R instead of E for 32-bit, i.e. RAX instead of EAX and so on)

Anyone with more recent knowledge who can enlighten me?

Re: How does this compare to 32bit? (Score: 2, Informative)

by on 2014-09-01 02:33 (#2RYE)

Instruction sycall is AMD64; for a 32-bit program, you would use an interrupt instead (int 80h since this program uses Linux system calls, could have been something else like int 21h for MS-DOS) and also possibly change the system call number and the way other parameters are passed to the system because the 32-bit kernel and the 64-bit kernel have different ways of handling these.

Everyone, feel free to correct my possible mistakes, I am not an expert.


Time Reason Points Voter
2014-09-01 10:47 Informative +1

Junk Status

Not marked as junk