如何将此代码转换为 MIPS？

Question

C++ 代码：

#include <iostream>
using namespace std;

int main()
{
    int num;
    int sum = 0;

    cout << " Enter a number : ";
    cin >> num;

    while ( num > 0 ) {
    sum += num % 10;
    num /= 10;
}

如何将其转换为 MIPS？

我知道，我可以使用 $HI 和 $LO 寄存器，但我无法实现。

.data 
error: .asciiz "The Number you entered is not valid"
input: .asciiz "Please enter a number"

.text 

main:
#GET NUMBER FROM USER
li $v0, 4 #load syscall print string
la $a0, input  #load adress of str1 into $a0
syscall   #make the syscall

#SAVE NUMBER
li $v0, 5 #load syscall read_int into $v0
syscall   #make the syscall
move $s0, $v0 #move the number read into $t0 now $t0=n

#make sure number is between 100 and 400
addi $t1, $zero, 400
addi $t2, $zero, 100 
ble $s0, $t2, EXIT 
bge $s0, $t1, EXIT 



loop: 
div $s0, $s1 
add $s2, $s2, $LO 
add $s0, $HI, $zero 
bgt $s0, $zero, loop 




end: 
li $v0, 10 
syscall


EXIT: 
li $v0, 4 #load syscall print string
la $a0, error  #load adress of error into $a0
syscall   #make the syscall

Answer 1

当你在 MIPS 中做 div 时，商进入$HI，余数进入$LO。如果 while 循环是您遇到的问题，那应该会有所帮助。

Sum: s2
Num: s0
10: s1

While:      # while num >0
div $s0, $s1. #  $s0/$s1    num/10
add $s2, $s2, $LO # sum += num%10
add $s0, $HI, $zero   # num /= 10
bgt $s0, $zero, While # if num >0 loop again

剩下的只是一个分支大于的循环。