代码在MARS中运行但不在QTSims中运行

Question

我编写的这个程序在MARS上完美运行，但是当我使用QTSIMS加载它时，它会停止工作并为每次计算返回零，有人可以告诉我为什么吗？

我不确定两者之间的区别是否诚实。

.globl main

主：

.text

li $v0, 4   # print string
la $a0, large   # load string
syscall

li $v0, 5       # prompt for integer
syscall
move $s0, $v0   # store input

#Below is the same but different strings and inputs

li $v0, 4
la $a0, largepicked
syscall

li $v0, 5
syscall
move $s1, $v0

li $v0, 4
la $a0, small
syscall

li $v0, 5
syscall
move $s2, $v0

li $v0, 4
la $a0, smallpicked
syscall

li $v0, 5
syscall
move $s3, $v0

计算因子

move $a0, $s0           # save large value to function
move $a1, $s1           # save small value to function
jal factmod             # compute factorial of (large!/small!)
move $s4, $v0           # store value

move $a0, $s1           # save small value to original factorial
jal factrl          # compute factorial
move $s5, $v0           # store value

#Repeat for second lottery
move $a0, $s2
move $a1, $s3
jal factmod
move $s6, $v0

move $a0, $s3
jal factrl
move $s7, $v0

计算赔率

div $s4, $s5
mflo $s4

div $s6, $s7
mflo $s6

mul $s4, $s4, $s6

将结果打印到控制台

li $v0, 4
la $a0, result
syscall

li $v0, 1
move $a0, $s4
syscall

li $v0, 4
la $a0, stopped
syscall

li $v0, 10
syscall

正常因子代码

factrl: sw $ra, 4($sp)      # save the return address
sw $a0, 0($sp)      # save the current value of n
addi $sp, $sp, -8   # move stack pointer
slti $t0, $a0, 2    # save 1 iteration, n=0 or n=1; n!=1
beq $t0, $zero, L1  # not less than 2, calculate n(n-1)!
addi $v0, $zero, 1  # n=1; n!=1
jr $ra          # now multiply

L1:     addi $a0, $a0, -1   # n = n-1
jal factrl      # now (n-1)!
addi $sp, $sp, 8    # reset the stack pointer
lw $a0, 0($sp)      # fetch saved (n-1)
lw $ra, 4($sp)      # fetch return address
mul $v0, $a0, $v0   # multiply (n)*(n-1)
jr $ra          # return value n!

大的阶乘！/小！

factmod: sw $ra, 8($sp)          # save the return address
sw $a0, 4($sp)          # save the value of large
sw $a1, 0($sp)          # save the value of small

addi $t0, $zero, 1      # set counter
lw $t1, 4($sp)          # set large
lw $t2, 0($sp)          # set small
move $v0, $t1           # set large as the numerator

loop:   addi $t0, $t0, 1        # increment counter
addi $t1, $t1, -1       # decrement large
mul $v0, $t1, $v0       # large * large - 1
    bge  $t0, $t2, done # if counter less  than small, loop
    j loop

done:   lw $ra, 8($sp)          # fetch return address
jr $ra          # return value

。数据

large:          .asciiz "Please enter the number of balls in the large pool: "
largepicked:    .asciiz "Please enter the number of balls picked from the large pool: "
small:          .asciiz "Please enter the number of balls in the second pool: "
smallpicked:    .asciiz "Please enter the number of balls picked from the second pool: "
result:     .asciiz "The odds are 1 in "

stopped:        .asciiz "\nStopped"

Answer 1

没关系，我用另一台电脑运行QtSpim并且它有效