How Strings Are Compared in Assembly | Beginner Tutorial | x86-64 Machine Code
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00:00 Why CMP fails for Strings
01:36 Coding strcmp() in Assembly
07:10 Testing strcmp()
8:55 Outputting match/no match
12:40 CHALLENGE: Check only N characters of string
;##### Code Below
exit:
xor rdi, rdi
mov rax, 60
syscall
print:
push rdi
call slen
pop rsi
mov rdx, rax
mov rax, 1
mov rdi, 1
syscall
ret
println:
push rdi
call slen
pop rsi
mov rdx, rax
mov rax, 1
mov rdi, 1
syscall
mov rax, 1
mov rdi, 1
lea rsi, [newline]
mov rdx, 1
syscall
ret
slen:
xor rcx, rcx
slen.loop:
mov al, [rdi + rcx]
cmp al, 0
je slen.ret
inc rcx
jmp slen.loop
slen.ret:
mov rax, rcx
ret
;#########