MIPS地址超出范围（MARS）快速排序

Question

我正在尝试编写一个快速排序代码，该代码将对指令位于http://www.cs.uni.edu/~fienup/cs1410s19/homework/hw7.pdf中的数组（其hw）进行排序

以下是代码。组装时程序运行正常，但运行时会在MARS中出现错误

   .data
array:  .word 6 3 1 4 5 2 3 8 9 7 5 
length: .word 11
NewLine: .asciiz "\n"

        .text
        .globl main


main:
        la $a0, array
        li $a1, 0
        lw $t0, length
        addi $a2, $t0, -1
        jal quickSort
        li $v0, 10       
        syscall 

quickSort:

        addi $sp, $sp, -20
        sw $s0, 4($sp) 
        sw $s1, 8($sp) 
        sw $s3, 16($sp)
        sw $ra, 20($sp)
        move $s0, $a0
        move $s1, $a1
        move $s2, $a2

        bge $s1, $s2, end_quickSort

        jal partition
        move $s3, $v0

        move $a0, $s0
        move $a1, $s1
        addi $a2, $s3, -1
        jal quickSort

        move $a0, $s0
        addi $a1, $s3, 1
        move $a2, $s2
        jal quickSort

end_quickSort:

        lw $s0, 4($sp)
        lw $s1, 8($sp)
        lw $s2, 12($sp)
        lw $s3, 16($sp)
        lw $ra, 20($sp)
        addi $sp, $sp, 20
        jr $ra


partition:

        addi $sp, $sp, -20

        sw $s0, 4($sp)
        sw $s1, 8($sp)
        sw $s2, 12($sp)
        sw $s3, 16($sp)
        sw $ra, 20($sp)

        move $s0, $a0
        move $s1, $a1
        move $2, $a2

        move $6, $s1 
        mul $s4, $s1, 4
        add $s4, $s0, $s4
        lw $s3, 0($s4)
        addi $t4, $s4, 4 

for:
        addi $t2, $s2, 1
        mul $t3, $t2, 4
        add $t3, $s0, $t3
for_compare:
        bge $t4, $t3, end_for
        lw $t5, 0($t4)
        bge $t5, $s3 if_end
        addi $s4, $s4, 4
        addi $t6, $t6, 1
        move $a1, $s4
        move $a2, $t4
        jal swap

end_for:
        move $a1, $s4 
        mul $t7, $s1 4
        add $t7, $s0, $t7
        move $a2, $t7
        jal swap
        lw $s0, 4($sp)
        lw $s1, 8($sp)
        lw $s2, 12($sp)
        lw $s3, 16($sp)
        lw $ra, 20($sp)
        addi $sp, $sp, 20
        move $v0, $t6
        jr $ra
if_end:
        addi $t4, $t4 4
        j for_compare
swap:
       lw $t0, 0($a1)
       lw $t1, 0($a2)
       sw $t0, 0($a2)
       sw $t1, 0($a1)
       jr $ra


addi $t0, $zero, 0
addi $t5, $zero, 0
while:
    bge $t5, $s7, exit
    lw $t6, array($t0)

    addi $t0, $t0, 4
    addi $t5, $t5, 1
    li $v0, 1
    move $a0, $t6
    syscall

    li $v0, 4
    la $a0, NewLine
    syscall
    j while
exit:
    li $v0, 10
    syscall

使用MARS，我得到以下信息：行60：运行时异常位于0x00400094：地址超出范围0x7fbffff4。我在做什么错了？