Question

我正在尝试获取用户输入（input = $ v0），然后将其与10（10 = $ t1）进行比较。如果输入小于10，我想打印'＆lt;'。如果输入大于10，我希望它打印'＆gt;'。我尝试了一些不同的东西，但由于某种原因它最终打印'＆lt;'和'＆gt;'。以及错误读取“程序已完成运行（从底部掉下来）”有人能告诉我我做错了什么吗？

    #where values are initialized
    addi $t1, $zero, 10 #number for comparison
    addi $t1, $zero, 60 #< less than 
    addi $t2, $zero, 62 #> greater than

    #Where things happen
    addi $v0, $zero, 5  # syscall 5 is to read integer syscall
    syscall             #get input from keyboard
    blt $v0, $t1, less  #go to less if less than 10
    bgt $v0, $t1, great #go to great if greater than 10

less:   #if input is less than 10
    addi $v0, $zero, 11 #print
    add $a0, $t1, $zero #copy $v0 to print
    syscall             #call for print 

great:  #if input is greater than 10
    addi $v0, $zero, 11 #print
    add $a0, $t2, $zero #copy $v1 to print
    syscall         #call for print

Answer 1

你需要以某种方式完成你的程序。例如，如果代码跳转到less:标签，因为您没有任何返回或跳转到完成程序的例程，执行只是继续great:部分。

因此，您应该从程序中退出另一个标签end:。在end:和less:执行系统调用后，您应该跳转到great:。

#where values are initialized
    addi $t1, $zero, 10 #number for comparison
    addi $t1, $zero, 60 #< less than 
    addi $t2, $zero, 62 #> greater than

    #Where things happen
    addi $v0, $zero, 5  # syscall 5 is to read integer syscall
    syscall             #get input from keyboard
    blt $v0, $t1, less  #go to less if less than 10
    bgt $v0, $t1, great #go to great if greater than 10
    #jump to end: (since there can also be an equal case)

less:   #if input is less than 10
    addi $v0, $zero, 11 #print
    add $a0, $t1, $zero #copy $v0 to print
    syscall             #call for print 
    #jump to end:

great:  #if input is greater than 10
    addi $v0, $zero, 11 #print
    add $a0, $t2, $zero #copy $v1 to print
    syscall         #call for print
    #jump to end:

end:
   #program exiting routine

我不确定退出例程的确切语法，但我相信你可以毫无困难地解决这个问题：）

希望这有帮助！

MIPS打印问题

1 个答案: