MIPS汇编范例复习过程.docx

1、MIPS汇编范例复习过程MIPS汇编范例mips汇编语言之实现swap函数 收藏 此程序用来交换两个整数已在pcspim下编译通过# programed by stevie zou # purpose:to swap two values # 10-15-2008 # # text segment # .text .globl mainmain: la $t0, number #读取两个整数并放入寄存器$t1,$t2 lw $t1, 0($t0) lw $t2, 4($t0) li $v0, 4 #打印msg1 la $a0, msg1 syscall li $v0, 1 #打印转换前$t1中

2、的值 move $a0, $t1 syscall li $v0, 4 #打印msg2 la $a0, msg2 syscall li $v0, 1 #打印转换前$t2中的值 move $a0, $t2 syscall move $t3, $t1 #关键部分，在寄存器间move数据 move $t1, $t2 move $t2, $t3 li $v0, 4 #打印msg3 la $a0, msg3 syscall li $v0, 1 #打印转换后$t1中的值 move $a0, $t1 syscall li $v0, 4 #打印换行符 /n la $a0, msg4 syscall li $v0

3、, 1 #打印转换后$t2中的值 move $a0, $t2 syscall# data segment # .datanumber: .word 12,34msg1: .asciiz the first number is:nmsg2: .asciiz nthe second number is:nmsg3: .asciiz nnow they are swapped as:nmsg4: .ascii n# end of file程序运行结果为：本文来自CSDN博客，转载请标明出处：mips汇编简单实例一个小计算器 收藏 其实开始的时候一直在看 mips的指令格式，看了、忘了，没什么效果。现

4、在通过这个例子，简单训练一下： mips汇编中：常用寄存器的使用；系统调用： 1(print_int),4(print_str),5(read_int),10(exit)；算术运算： add,sub,mul,div；逻辑运算及跳转；上代码：(汇编写的少，代码书写、风格还很差劲，感谢请大虾指教)：view plaincopy to clipboardprint?#sample example a small calculater .text # text section .globl main # call main by SPIM main: la $t0, value # load addr

5、ess value into $t0 la $a0,msg0 li $v0,4 syscall #print please choose the operation: li $v0, 5 syscall sw $v0, 8($t0) la $a0,msg1 li $v0,4 syscall #print first num: li $v0, 5 syscall sw $v0, 0($t0) la $a0,msg2 li $v0,4 syscall #print second num: li $v0, 5 syscall sw $v0, 4($t0) #read the other num la

6、 $a0,newline li $v0,4 syscall #print n lw $t1, 0($t0) # load the first num lw $t2, 4($t0) # load the second num lw $t3, 8($t0) # load the operation beq $t3,1,addOp # if + beq $t3,2,subOp # if - beq $t3,3,mulOp # if * beq $t3,4,divOp # if / addOp: add $t4, $t1, $t2 # $t1 + $t2 = $t4 sw $t4, 12($t0) #

7、 la $t5,addFlag j printResult subOp: sub $t4, $t1, $t2 # $t1 - $t2 = $t4 sw $t4, 12($t0) la $t5,subFlag j printResult mulOp: mul $t4, $t1, $t2 # $t1 * $t2 = $t4 sw $t4, 12($t0) la $t5,mulFlag j printResult divOp: div $t4, $t1, $t2 # $t1 / $t2 = $t4 sw $t4, 12($t0) la $t5,divFlag j printResult printR

8、esult: lw $a0,0($t0) li $v0,1 syscall #read first number la $a0,0($t5) li $v0,4 syscall #print opflag lw $a0,4($t0) li $v0,1 syscall #print second number la $a0,equalStr li $v0,4 syscall #print = lw $a0,12($t0) li $v0,1 syscall # print sum result j exit exit: la $a0,newline li $v0,4 syscall #print n

9、 li $v0,10 syscall # exit # data section .data value: .word 0, 0, 0 ,0 ,0 # 0: first num ,4 : second num , 8 : operation , 12:result msg0 : .asciiz please choose the operation(14):ntt1 : +,addition ntt2 : -,subtracterntt3 : * multiplication ntt4 : /,divisionn msg1 : .asciiz first num: msg2 : .asciiz

10、 second num: addFlag : .asciiz + subFlag : .asciiz - mulFlag : .asciiz * divFlag : .asciiz / equalStr : .asciiz = newline : .asciiz n=n #sample example a small calculater.text # text section.globl main # call main by SPIMmain: la $t0, value # load address value into $t0 la $a0,msg0 li $v0,4 syscall

11、#print please choose the operation: li $v0, 5 syscall sw $v0, 8($t0) la $a0,msg1 li $v0,4 syscall #print first num: li $v0, 5 syscall sw $v0, 0($t0) la $a0,msg2 li $v0,4 syscall #print second num: li $v0, 5 syscall sw $v0, 4($t0) #read the other num la $a0,newline li $v0,4 syscall #print n lw $t1, 0

12、($t0) # load the first num lw $t2, 4($t0) # load the second num lw $t3, 8($t0) # load the operation beq $t3,1,addOp # if + beq $t3,2,subOp # if - beq $t3,3,mulOp # if * beq $t3,4,divOp # if / addOp: add $t4, $t1, $t2 # $t1 + $t2 = $t4 sw $t4, 12($t0) # la $t5,addFlag j printResultsubOp: sub $t4, $t1

13、, $t2 # $t1 - $t2 = $t4 sw $t4, 12($t0) la $t5,subFlag j printResultmulOp: mul $t4, $t1, $t2 # $t1 * $t2 = $t4 sw $t4, 12($t0) la $t5,mulFlag j printResultdivOp: div $t4, $t1, $t2 # $t1 / $t2 = $t4 sw $t4, 12($t0) la $t5,divFlag j printResult printResult: lw $a0,0($t0) li $v0,1 syscall #read first number la $a0,0($t5) li $v0,4 syscall #print opflag lw $a0,4($t0) li $v0,1 syscall #print second nu