MIPS汇编语言实现选择排序算法
1.流程图
2.C代码
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
int main()
{
uint32_t num = 10 ;
uint32_t *arr = malloc(sizeof(uint32_t)*num);
printf("Please input:");
printf("%u",num);
printf(" unsigned integer, with one integer in one line:\n");
for(uint32_t i = 0 ; i < num ; i ++ )
{
scanf("%u",&arr[i] );
}
for(uint32_t i = 0 ; i < num ; i ++ )
{
uint32_t max = i ;
for( uint32_t j = i + 1 ; j < num ; j ++ )
{
if(arr[j] > arr[max])
{
max = j ;
}
}
uint32_t temp = arr[i] ;
arr[i] = arr[max];
arr[max] = temp ;
}
printf("Result: ");
for(uint32_t i = 0 ; i < num ; i ++ )
{
printf(" ");
printf("%u",arr[i]);
}
printf("\n");
free(arr);
}
3.MIPS代码（附注释）
.text
.globl main
main:
la $a0, prompt1 # 打印 prompt1
li $v0, 4
syscall
la $t0, num # 把10这个数字存到寄存器t0中
lw $t0, ($t0)
add $a0, $t0, $0 # 打印数字10
li $v0, 1
syscall
la $a0, prompt2 # 打印 prompt2
li $v0, 4
syscall
sll $a0, $t0, 2 # 为数组申请空间
li $v0, 9
syscall
add $t1, $v0, $0 # t1寄存器中存数组首地址
add $t2, $0, $0 # 把临时变量i存到寄存器t2中
inputLoop:
slt $t3, $t2, $t0 # for循环判断条件如果i < 10 置t3为1否则置t3为0
beq $t3, $0, inputLoopBreak
li $v0, 5 # 读一个数字
syscall
sll $t3, $t2, 2 # 求出i的偏移量
add $t3, $t1, $t3 # 找到arr[i]的地址
sw $v0, ($t3) # arr[i] = 输入的数字
j inputLoopCont
inputLoopCont:
addi $t2, $t2, 1 # i ++
j inputLoop
inputLoopBreak:
add $t2, $0, $0 # i = 0
outerLoop:
slt $t3, $t2, $t0 # for循环判断条件如果i < 10 置t3为1否则置t3为0
beq $t3, $0, outerLoopBreak
add $t4, $t2, $0 # max = i
addi $t5, $t2, 1 # j = i + 1
innerLoop:
slt $t3, $t5, $t0 # for循环判断条件如果j < 10置t3为1否则置t3为0
beq $t3, $0, innerLoopBreak
# get arr[j]
sll $t3, $t5, 2 # 求出j的偏移量
add $t3, $t1, $t3 # 找到arr[j]
lw $t3, ($t3) # 把t3中存放的数字拿出来
# get arr[maxIndex]
sll $t6, $t4, 2 # 找到max的偏移量
add $t6, $t1, $t6 # 找到arr[max]
lw $t6, ($t6) # 把t6中存放的数字拿出来
slt $t3, $t3, $t6 # 判断arr[j]与arr[max]大小
bne $t3, $0, afterReplace
replace:
add $t4, $t5, $0 # max = j
j afterReplace
afterReplace:
j innerLoopCont # continue
innerLoopCont:
addi $t5, $t5, 1 # j++
j innerLoop
innerLoopBreak:
beq $t2, $t4, afterSwap # 如果 i = max 不交换
swap:
sll $t3, $t2, 2 # 计算i偏移量
add $t3, $t1, $t3 # 求出arr[i]
sll $t5, $t4, 2 # 计算max偏移量
add $t5, $t1, $t5 # 求出arr[max]
lw $t6, ($t3) # 取出arr[i]
lw $t7, ($t5) # 取出arr[max]
sw $t7, ($t3) # 交换
sw $t6, ($t5)
j afterSwap
afterSwap:
j outerLoopCont # 继续循环
outerLoopCont:
addi $t2, $t2, 1 # i++
j outerLoop # 进入外层循环
outerLoopBreak:
la $a0, result
li $v0, 4
syscall
add $t2, $0, $0 # i = 0
outputLoop:
slt $t3, $t2, $t0 # 判断 i < 10 是否成立
beq $t3, $0, outputLoopBreak
la $a0, space # 打印空格
li $v0, 4
syscall
sll $t3, $t2, 2 # 求出i的偏移量
add $t3, $t1, $t3
lw $a0, ($t3) # 把t3中存放的数字拿出来存入a0
li $v0, 1 # 打印数字
syscall
j outputLoopCont
outputLoopCont:
addi $t2, $t2, 1 # i++
j outputLoop
outputLoopBreak:
la $a0, newline # 打印换行
li $v0, 4
syscall
li $v0, 10 # 退出
syscall
.data # 数据声明模块
prompt1:
.asciiz "Please input "
prompt2:
.asciiz " unsigned integers, with one integer in one line:\n"
result:
.asciiz "Result:"
space:
.asciiz " "
newline:
.asciiz "\n"
num:
.word 0x0000000a
