我正在尝试计算文件中的字符数，我已经读取了文件并将其存储在数组中，我开始只用一个字母（a）进行处理，剩下的我就去做，我面临的问题是，当我加载数组的地址并检查数组中第一个元素的值是否为字母（a）时，如果不是，则分支为字母（b），否则为该值是相同的，我将计数器的值递增，然后转到下一个地址。
问题是我尝试了一种方法，但是它始终使（$ t0）的值保持不变（97），所以我尝试了另一种解决方案，但是它似乎不起作用
任何想法或帮助将不胜感激
.data
.align 2
A: .space 10000 # space for 10000 Char
file: .asciiz "input.txt" # the txt file is in the same dirictory as MARS
tool and the source code
error: .asciiz "File does not exist"
.text
.globl main
main:
la $t0, A
# Open file for reading
li $v0, 13 # system call for open file
la $a0, file # input file name
li $a1, 0 # flag for reading
li $a2, 0 # mode is ignored
syscall # open a file
move $s6, $v0 # save the file descriptor
bltz $s6,noFile
# checking the value of $s6 if it saved values means the file exist if not
there's not file
# if file is not found exit - Branch if $a0 is 0 which mean no data
# reading from file to Array (A)
li $v0, 14 # reading from file
move $a0, $s6 # file descriptor
la $a1, A # address of buffer from which to read
li $a2, 10000
syscall # read from file
CountA:
lb $t0 , 0($a1)
bne $t0,'a', CountB
addi $t1,$t1,1 #counter
addi $a1,$a1,4 # to move to next address
addi $t0,$t0,1 # to incr t0 to check for next char
b CountA
CountB:
# not completed yet
exit:
# Close the file
li $v0, 16 # system call for close file
move $a0, $s0 # file descriptor to close
syscall # close file
li $v0, 10 # Exit
syscall
noFile: # if file is not found show message and exit
li $v0, 4
la $a0,error #load error msg
syscall # print error msg
li $v0, 10 # Exit
syscall
input.txt的示例
a
a
a
b
b
c
c
d