Question

基本上我有一个实验室，它是关于使用MIPS执行二分查找我试图存储该值，但似乎答案不正确，并且该值无法存储在我想要的寄存器中我无法弄清楚问题出在哪里我试图搜索15的索引并将答案存储到$s3。

以下是我的代码：

# load $s0: base address
# load $s1: array size
#      $s2: the search element
# return index at $v0
.text 
.globl main
main:
    # perform the first test
    addi $a1, $zero, 15
    jal  binary_search
    add  $s3, $v0,   $zero

exit:
    li $v0, 10
    syscall

binary_search:
    la   $s0, my_array           # load the base address to $s0
    add  $a0, $zero, $zero       # $a0 is now the first index 0
    lw   $s1, array_size         # load the array size to $s2
    addi $s1, $s1,  -1           # now $s1 is the last index
    add  $s2, $zero, $a1         # now store the search element into $s2

    j do_loop                    # do the loop

do_loop:    
    add $t0, $s1,   $a0          # have a temp reg to calculate the sum of  high and low
    sra $t1, $t0,   1            # store mid index value into $t1
    add $t1, $t1,   $s0          # move to the arr[middle]
    beq $t1, $s2,   return       # if the arr[mid] is equal to search value, return mid
    slt $t2, $t1,   $s2          # if mid < search, $t2 = 1
    beq $t2, $zero, front_half   # if mid> search, go left
    j   back_half                # if mid< search, go right 

front_half:
    add $s1, $t1, -1             # modify the max, max=mid-1
    j do_loop                    # back to the loop
back_half:
    addi $t1, $t1,   1
    add  $a0, $zero, $t1         # modify the min, min= mid+1
    j    do_loop                 # back to the loop

return: 
    add $ra, $zero, $t1
    jr  $ra

.data
my_array:   .word 1, 4, 5, 7, 9, 12, 15, 17, 20, 21, 30 
array_size: .word 11

MIPS中的二进制搜索不起作用

0 个答案: