MIPS——分支语句

1 li $t1,immediate     #load immediate，立即数可正可负
2 la $t1,address       #load address
3 move $t1,$t2         #move $t2 to $t1
4 syscall              #打印字符串时，将要输出的字符串的地址存到$a0,将$v0设置成4

 1 #include<stdio.h>
 2 
 3 int main()
 4 {
 5     int a, b;
 6     scanf("%d", &a);
 7     scanf("%d", &b);
 8     if (a > b)  printf("YES\n");
 9     else    printf("NO\n");
10 
11     return 0;
12 }

.data
      msg_yes:  .asciiz  "YES"
      msg_no:   .asciiz   "NO"     #定义两个字符串
  
.text
     li $v0,5
    syscall                       #读入a
    move $t0,$v0            #syscall读入的a存在$v0,要将它及时的转移到其它寄存器

    li $v0,5
    syscall
    move $t1,$v0            #读入b

    bgt $t0,$t1,L1           
        la $a0,msg_no   #else
        li $v0,4
        syscall
        j exit                 #要及时跳转到结束，否则L1中的指令也会执行

        L1:                   #if
            la $a0,msg_yes
            li $v0,4
            syscall
        
    exit:
       li $v0,10
       syscall                    #$v0  == 10,运行终止