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Diffstat (limited to 'print-repeat.asm')
| -rw-r--r-- | print-repeat.asm | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/print-repeat.asm b/print-repeat.asm new file mode 100644 index 0000000..3856abd --- /dev/null +++ b/print-repeat.asm @@ -0,0 +1,40 @@ +; 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 |