36 lines
484 B
ArmAsm
36 lines
484 B
ArmAsm
%define STDOUT 1
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global _ft_putchar
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global ft_putchar
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section .bss
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char: resb 1
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section .text
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; int ft_putchar(int c)
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_ft_putchar:
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ft_putchar:
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; save c value
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push rdi
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; int write(int fd, char *str, size_t len)
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lea rsi, [char] ; char *str
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mov [rsi], dil
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mov rdi, STDOUT ; int fd
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mov rdx, 1 ; size_t len
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mov rax, WRITE
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syscall
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cmp rax, 0
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jl err
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; success case then return c
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pop rax
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ret
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err:
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; error case then return -1
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pop rax
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mov rax, -1
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ret
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