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我正在編寫一些MIPS代碼來獲取一串ASCII數字並將該字符串轉換爲一個整數。該字符串由用戶輸入並且最多可以爲10位數字。我的代碼工作正常，並使用顯式的方法來執行循環加法後，乘以10的冪的最小有效數字的字符串由數組索引確定，從最後輸入的數字（10^0）開始到第一個數字輸入（10^n，n =數組中的位數）。在MIPS /彙編程序中將ASCII數字的字符串轉換爲int
我想知道是否有更快或更短的替代方法來編寫。特別是，我想知道如果使用邏輯位移可能會縮短此過程。任何想法優化或改善這個代碼將不勝感激！另外，作爲一個附註，我想使用jal調用gets和readInt子例程，但是因爲gets和readInt都調用子例程，所以在main方法中使用jal來調用gets或readInt會導致問題。任何想法如何解決這個問題？再次感謝 乾杯
PS：對不起，這個代碼中的註釋的格式，複製和MARS模擬器入堆棧溢出文本框中粘貼引起對準被關閉：/
#IO
#Prompts user to input 10 ascii digits into an array
#Converts the string of digits into a single int
#Also handles any number of digits between 1 and 10
#Returns 0 if non-digit chars are entered into the string
.data #declaration of vars follows
array: .space 11 #reserves space for a 10 elem array
char: .space 2
prompt: .asciiz "Please enter 10 numbers, then press ENTER: \n"
null: .asciiz ""
space: .ascii " "
newline: .asciiz "\n"
.text #instructions follow
main:
la $a0, prompt #load prompt message into $a0 for syscall
li $v0, 4 #load syscall to print string
syscall #print prompt message
j readInt #call readInt function to get user input string
gets: #read multiple chars from keyboard buffer until ENTER key,
#add NULL char and store into buffer pointed to by *array
#passed to the subroutine
la $s1, array #set base address of array to s1
loop: #start of read loop
jal getc #jump to getc subroutine
lb $t0, char #load the char from char buffer into t0, stripping null
sb $t0, 0($s1) #store the char into the nth elem of array
lb $t1, newline #load newline char into t1
beq $t0, $t1, done #end of string? jump to done
addi $s1, $s1, 1 #increments base address of array
j loop #jump to start of read loop
getc: #read char from keyboard buffer and return ascii value
li $v0, 8 #call code for read string
la $a0, char #load address of char for read
li $a1, 2 #length of string is 1byte char and 1byte for null
syscall #store the char byte from input buffer into char
jr $ra #jump-register to calling function
readInt: #read string of ascii digits, store into a local variable and
#convert into integer, return that int unless string contains
#non-integers
j gets #let s1 be top address of array, let s0 be the digitcounter
done: #let s2 be the sum total
addi $s1, $s1, -1 #reposition array pointer to last char before newline char
la $s0, array #set base address of array to s0 for use as counter
addi $s0, $s0, -1 #reposition base array to read leftmost char in string
add $s2, $zero, $zero #initialize sum to 0
li $t0, 10 #set t0 to be 10, used for decimal conversion
li $t3, 1
lb $t1, 0($s1) #load char from array into t1
blt $t1, 48, error #check if char is not a digit (ascii<'0')
bgt $t1, 57, error #check if char is not a digit (ascii>'9')
addi $t1, $t1, -48 #converts t1's ascii value to dec value
add $s2, $s2, $t1 #add dec value of t1 to sumtotal
addi $s1, $s1, -1 #decrement array address
lp: #loop for all digits preceeding the LSB
mul $t3, $t3, $t0 #multiply power by 10
beq $s1, $s0, FIN #exit if beginning of string is reached
lb $t1, ($s1) #load char from array into t1
blt $t1, 48, error #check if char is not a digit (ascii<'0')
bgt $t1, 57, error #check if char is not a digit (ascii>'9')
addi $t1, $t1, -48 #converts t1's ascii value to dec value
mul $t1, $t1, $t3 #t1*10^(counter)
add $s2, $s2, $t1 #sumtotal=sumtotal+t1
addi $s1, $s1, -1 #decrement array address
j lp #jump to start of loop
error: #if non digit chars are entered, readInt returns 0
add $s2, $zero, $zero
j FIN
FIN:
li $v0, 1
add $a0, $s2, $zero
syscall
li $v0, 10 #ends program
syscall