我看过那些在堆栈溢出时提出这个问题的人，但是我似乎无法从对它们的回复中把任何东西拼凑起来，所以我只是问它特别关注我的代码。
我有一块（破碎的）MIPS代码应该是一个合并分区。但是，当我尝试运行它时，我收到此错误：路径错误\ Desktop \ mergesort.asm第8行：0x00003160的运行时异常：地址超出范围0xfffffffc
我无法弄清楚为什么保存返回地址会导致问题。任何帮助将不胜感激
#main method for mergesort
.data 0x0
.globl array
.globl b_array
num_of_el: .word 4
array: .space 3200
b_array: .space 3200
#strings to be printed
comm_space: .asciiz ", "
string_1: .asciiz "\nPlease enter the number of elements you'd like to sort (No more than 100).\n"
string_2: .asciiz "\nPlease enter "
string_2b: .asciiz " integers to be mergesorted, one per line:\n"
string_3: .asciiz "\nHere is the sorted data:\n"
#start of code
.text 0x3000
.globl main
main:
li $v0, 4 #system call code to print
la $a0, string_1 #load address of first string
syscall
li $v0, 5 #syscall to read int
syscall
move $s0, $v0 #move from $t0 to $s0
sw $s0, num_of_el
li $v0, 4 #system call code to print
la $a0, string_2 #load address of second string part one
syscall
li $v0, 1 #system call code to print int
lw $a0, num_of_el #load word - number of elements
syscall
li $v0, 4 #system call code to print
la $a0, string_2b #load address of second string part two
syscall
fill_arr:
addi $t0, $0, 0 #initialize array pointer
fill_array_loop:
li $v0, 5 #syscall to read int
syscall
move $s1, $v0 #move from t0 to s0
sw $s1, array($t0) #store into array at pointer
addiu $t0, $t0, 4 #increment counter
lw $t1, num_of_el #load number of elements into t1
add $t1, $t1, $t1 #double value of t1
add $t1, $t1, $t1 #quadruple value of t1 to compare to array pointer
bne $t1, $t0, fill_array_loop
addi $a0, $0, 0 #array pointer low (0)
lw $t2, num_of_el #load size of array
sll $t2, $t2, 2 #multiply by 4 to get
addi $a1, $t2, -4 #end address -4
jal mergesort
li $v0, 4 #system call code to print
la $a0, string_3 #load address of second string part two
syscall
print_array:
addi $t0, $0, 0 #initialize array pointer
print_array_loop:
li $v0, 1 #system call code to print int
lw $a0, b_array($t0) #load word - element of array
syscall
li $v0, 4 #system call code to print
la $a0, comm_space #load address of second string part two
syscall
addiu $t0, $t0, 4 #increment counter
lw $t1, num_of_el #load number of elements into t1
add $t1, $t1, $t1 #double value of t1
add $t1, $t1, $t1 #quadruple value of t1 to compare to array pointer
bne $t1, $t0, print_array_loop
end_main:
li $v0, 10 #terminate programm
syscall
第二个程序：
.text
.globl mergesort
mergesort:
addi $sp, $sp, -12 # Make room on stack for saving $ra and $fp
sw $ra, 0($sp) # Save $ra
sw $a0, 4($sp) # store low
sw $a1, 8($sp) # store high
beq $a0, $a1 end_mergesort #only execute if low < high
add $s0, $a1, $a0 #sum of low and high
div $s0, $s0, 2 #divide by 2 (this is mid)
add $a1, $s0, $0 #make argument2 the mid for mergesort call
jal mergesort
lw $a1, 8($sp) # Load high
add $s0, $a1, $a0 #sum of low and high
div $s0, $s0, 2 #divide by 2 (this is mid)
add $a0, $s0, 4 #make argument1 mid +4
jal mergesort # Call recursively on the second half of the array
lw $a0, 4($sp) # Load low
lw $a1, 8($sp) # Load high
add $s0, $a1, $a0 #sum of low and high
div $s0, $s0, 2 #divide by 2 (this is mid)
add $a2, $0, $a1 #put high in argument3
add $a1, $s0, $0 #put mid in argument 2
jal merge # Merge the two array halves
end_mergesort:
lw $ra, 0($sp) # Load the return address from the stack
lw $a0, 4($sp) # store low
lw $a1, 8($sp) # store high
addi $sp, $sp, 12 # Adjust the stack pointer
jr $ra # Return
第三程序：
.text
.globl merge
merge:
addi $sp, $sp, -4 # Adjust the stack pointer
sw $ra, 0($sp) # Store the return address on the stack
add $t0, $a0, $0 #i is low($a0)
add $t1, $a1, 4 #j is mid + 4
add $t2, $0, $0 #k points to b_array
while1:
bgt $a1, $t0, while2 #exit loop if m>i
bgt $t2, $a2, while2 #exit loop if j>h
lw $t3, array($t0) #load array[i] into $t3
lw $t4, array($t1) #load array[j] into $t4
ble $t3, $t4, if #if array[i] <= array[j]
beq $0, $0, else #jump to else
if:
sw $t3, b_array($t2) #store array[i] into b_array[k]
add $t0, $t0, 4 #increment i
add $t2, $t2, 4 #increment k
j while1
else:
sw $t4, b_array($t2) #store array[j] into b_array[k]
add $t1, $t1, 4 #increment j
add $t2, $t2, 4 #increment k
j while1
while2:
bgt $a1, $t0, while3 #exit loop if m>i
lw $t3, array($t0) #load array[i] into $t3
sw $t3, array($t2) #store array[i] into b_array[k]
add $t0, $t0, 4 #increment i
add $t2, $t2, 4 #increment k
j while2
while3:
bgt $t2, $a2, merge_end #exit loop if j>h
lw $t4, array($t1) #load array[j] into $t4
sw $t4, b_array($t2) #store array[j] into b_array[k]
add $t1, $t1, 4 #increment j
add $t2, $t2, 4 #increment k
j while1
merge_end:
lw $ra, 0($sp) # Store the return address on the stack
addi $sp, $sp, 4 # Adjust the stack pointer
jr $ra #return