Answer to Question #304349 in Assembler for kaic

Question

Write an Assembly Language code that rearranges any four (2) strings of doubleword values in an array expressing yourself during MCO with this Covid-19 pandemic. Then request a user to enter a name, before the program will reverse the name. All strings should be present in different colors. Repeat the output 2 times.

Answer 1

; nasm
string_length:
	    xor rax, rax
	  .iter:
	    cmp byte[rdi+rax], 0x0
	    je .break
	    inc rax
	    jmp .iter
	  .break:
	    ret

print_string:
	    call string_length
	  .print:
	    mov rsi, rdi
	    mov rdi, 0x1
	    mov rdx, rax
	    mov rax, 0x1
	    syscall
	    ret

print_char:
	    push rdi
	    mov rax, 0x1
	    mov rdi, 0x1
	    mov rsi, rsp
	    mov rdx, 0x1
	    syscall
	    pop rdi
	    ret

read_char:
	    push 0x0
	    xor rax, rax
	    xor rdi, rdi
	    mov rsi, rsp
	    mov rdx, 0x1
	    syscall
	    pop rax
	    ret

read_word:
	    push rsi-0x1
	    push rdi                
	    xor r8, r8
	    xor r9, r9
	  .iter:
	    call read_char          
	    mov rdi, [rsp]          
	    mov rsi, [rsp+0x1]      
	    cmp rax, 0x9
	    je .check
	    cmp rax, 0xa
	    je .check
	    cmp rax, 0x20
	    je .check
	    mov r9, 0x1             
	    cmp rax, 0x0            
	    je .check               
	    cmp r8, rsi             
	    je .err                
	    mov [rdi+r8], al       
	    inc r8                
	    jmp .iter
	  .check:
	    test r9, r9            
	    je .iter               
	    mov [rdi+r8], byte 0x0 
	    mov rax, rdi           
	    mov rdx, r8             
	    jmp .end
	  .err:
	    xor rax, rax
	  .end:
	    pop rdi               
	    pop rsi              
	    ret