49 lines
1.5 KiB
ArmAsm
49 lines
1.5 KiB
ArmAsm
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;; Pure assembly, library-free Linux threading demo
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bits 32
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global _start
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;; sys/syscall.h
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%define SYS_write 1
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%define SYS_exit 60
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;; unistd.h
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%define STDOUT 1
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section .data
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hello: db `Goodbye\10`
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section .text
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_start:
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mov eax, 9234d ; The number we're processing; this is
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; the dividend target for the div operation
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xor esi, esi ; fast zero
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.loop:
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mov edx, 0d ; counter
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mov ebx, 10d ; divisor
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div ebx
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add edx, 48d ; the remainder, plus the ASCII for '0'
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; the quotient is put into eax
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push edx ; onto the stack
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inc esi ; Increment counter
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cmp eax, 0d ; if EAX is zero, we're done.
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jz .print
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jmp .loop
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.print:
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cmp esi, 0d ; if counter is zero, we're done.
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jz .exit
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dec esi ; decrement the counter
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pop ecx ; copy the address of the stack pointer to edx
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mov edx, 1 ; One byte
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mov ebx, STDOUT ; To stdout
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int SYS_write ; Do it!
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jmp .print
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.exit:
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mov esi, hello ; move the contents of the stack pointer into ECX
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mov ecx, 6 ; One byte
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mov ebx, STDOUT ; To stdout
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mov eax, SYS_write ; Do it!
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mov edi, 0 ; Success!
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mov eax, SYS_exit ; Do it!
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syscall
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