ARM Assembly问题输出正确的字符串(或根本没有任何字符串)

时间:2018-10-16 05:25:48

标签: assembly arm

我正在尝试将用户输入的数字与100进行比较,如果该数字大于或等于100,则打印“该数字大于或等于”,如果小于100,则进行相应打印。它可以很好地处理输入部分,但是在接受输入后程序立即结束。我对组装非常陌生,这是我第二天开始工作,所以请放轻松。感谢您的帮助!

.global main
main:

prompt: 
    ldr r0, = numPrompt
    bl printf   

get_input:
    ldr r0, =numInputPattern 
    sub sp, sp, #4
    mov r1, sp
    bl scanf
    ldr r1, [sp, #0]
    add sp, sp, #4

printinputasNum:
    cmp r0, #100    @compare num in r0 to 100
    bne Test1   @if not equal, jump to Test1
    ldr r0, = greaterorequalOutput 
    bl printf
    b   ExitAll
Test1:  blt Test2
    ldr r0, = lessthanOutput
    bl printf
    b   ExitAll
Test2:  ldr r0, = greaterorequalOutput
ExitAll:

myexit:
    mov r7, #0x01
    svc 0

.data

    .balign 4
    numPrompt: .asciz "Input a number: "

    .balign 4
    numInputPattern: .asciz "%d"

    .balign 4
    lessthanOutput: .asciz "The input number is less than 100 \n"

    .balign 4
    greaterorequalOutput: .asciz "The input number is greater than or equal to 100 \n"

.global printf
.global scanf

0 个答案:

没有答案