Задача на ассэмблере

 extern puts 

 

section .data 

    str1    db      "Hello, ",0 

    str2    db      "World!",0xa,0 

 

section .bss 

    result  resb    256 

 

section .text 

    global main 

 

main: 

    push rbp 

    mov rbp, rsp 

 

    lea rdi, [result] 

    lea rsi, [str1] 

    lea rdx, [str2] 

    call string_cat 

     

    lea rdi, [result] 

    call puts                   ; Hello, World! 

     

    xor eax, eax 

     

    leave 

    ret 

 

string_cat: 

    push rbp 

    mov rbp, rsp 

     

    mov qword [rbp - 8],  0     ; size 

    mov qword [rbp - 16], rdi   ; dest 

    mov qword [rbp - 24], rsi   ; str1 

    mov qword [rbp - 32], rdx   ; str2 

     

    jmp .cp_first_str 

 

.cp_first_str_loop: 

    mov rax, qword [rbp - 24] 

    lea rdx, [rax + 1] 

    mov qword [rbp - 24], rdx 

    mov rcx, qword [rbp - 16] 

    mov rdx, qword [rbp - 8] 

    add rdx, rcx 

    movzx eax, byte [rax] 

    mov byte [rdx], al 

    inc qword [rbp - 8] 

 

.cp_first_str: 

    mov rax, qword [rbp - 24] 

    movzx eax, byte [rax] 

    cmp al, 0 

    jne .cp_first_str_loop 

    jmp .cp_second_str 

 

.cp_second_str_loop: 

    mov rax, qword [rbp - 32] 

    lea rdx, [rax + 1] 

    mov qword [rbp - 32], rdx 

    mov rcx, qword [rbp - 16] 

    mov rdx, qword [rbp - 8] 

    add rdx, rcx 

    movzx eax, byte [rax] 

    mov byte [rdx], al 

    inc qword [rbp - 8] 

 

.cp_second_str: 

    mov rax, qword [rbp - 32] 

    movzx eax, byte [rax] 

    cmp al, 0 

    jne .cp_second_str_loop 

     

    leave 

    ret