50 lines
635 B
NASM
50 lines
635 B
NASM
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; Assembly "Hello, World!" for Linux
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;
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; Properly defined in <sys/syscall.h>
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%define SYS_exit 1
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%define SYS_write 4
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section .text
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global _start
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_start:
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; gdb doesn't like to stop at the entry point address, so
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; we put a nop here for pure convenience
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nop
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write_hello:
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mov edx, hello_len
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mov ecx, hello
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.loop:
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mov eax, SYS_write
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mov ebx, 1 ; stdout
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int 80h
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cmp eax, -4096
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ja error
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add ecx, eax
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sub edx, eax
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jnz .loop
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ok:
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mov eax, SYS_exit
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xor ebx, ebx
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int 80h
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hlt
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error:
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mov eax, SYS_exit
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mov ebx, 1 ; Error
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int 80h
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hlt
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section .rodata
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hello: db "Hello, World!", 10
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hello_len equ $-hello
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