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; Version : 2.0
; Last update : 3/1/2019
; Licence : GPLv3
; Description : Ever wanted to print something 10000 times really fast? Well, this program does exactly that. (This is ~4x faster than what gcc -O3 -march=native outputs from a normal C implementation)
section .data
Install: db 'Install ' ;The first 8 bytes of the message
Gentoo: db 'Gentoo!', 0xA ;The second 8 bytes of the message
section .text
global _start
_start:
xor ecx,ecx ;0 out the counter registor
ALIGN 16 ;Align the stack to 16 bytes
loop: inc ecx ;increment the counter every loop
;;Push the message to the stack, (needs to be done in reverse)
push qword[Gentoo]
push qword[Install]
test ecx,8192 ;test for most signficant 1 bit in 10,000
je loop
test ecx,1024 ;test for next most signficant 1 bit in 10,000
je loop
cmp ecx,10000 ;check for full number when both tests pass
jnz loop ;continue if number is not exact
;; e instead of r prefixes are used since that's faster. This is indeed a 64 bit syscall though. rsi=memory location to start printing, rdx=num of bytes to print
mov eax,1 ;sys_write
mov edi,1 ;fd = STDOUT_FILENO
mov edx,160000 ;hardcoded num of bytes to print since we know how many times we print
mov rsi,rsp ;the value of rsp is the start of where the text is, so we mov that to rsi for syscall
syscall
exit: mov eax,60 ;sys_exit
xor edi,edi ;return 0
syscall ;do sys_exit
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