《汇编语言 基于x86处理器》第九章字符串与数组部分的代码
2021-06-28 20:06
标签：wait hex 处理器 err result show color 逗号 中间 ? 书中第九章的程序，主要讲了 ● 代码，Irvine32 中的字符串库函数代码范例 ■ 输出结果 ● 二维表下标引用 ● 代码，冒泡排序，二分搜索 《汇编语言 基于x86处理器》第九章字符串与数组部分的代码 标签：wait hex 处理器 err result show color 逗号 中间 原文地址：https://www.cnblogs.com/cuancuancuanhao/p/9648847.html 1 INCLUDE Irvine32.inc
2
3 .data
4 str1 BYTE "abcde////", 0
5 str2 BYTE "ABCDE", 0
6 msg0 BYTE "Upper case: ", 0
7 msg1 BYTE "str1 == str2", 0
8 msg2 BYTE "str1 ", 0
9 msg3 BYTE "str1 > str2", 0
10 msg4 BYTE "Length of str1: ", 0
11 msg5 BYTE "Trimming: ", 0
12
13 .code
14 main PROC
15 mov edx, OFFSET str1
16 call WriteString
17 call crlf
18
19 call trim_string
20 call upper_case
21 call compare_strings
22 call print_length
23 call waitmsg
24 exit
25 main ENDP
26
27 trim_string PROC ; 去掉结尾的指定字符
28 INVOKE Str_trim, ADDR str1, ‘/‘
29 mov edx, OFFSET msg5
30 call WriteString
31 mov edx, OFFSET str1
32 call WriteString
33 call Crlf
34 ret
35 trim_string ENDP
36
37 upper_case PROC ; 小写转大写
38 mov edx, OFFSET msg0
39 call WriteString
40 INVOKE Str_ucase, ADDR str1
41 mov edx, OFFSET str1
42 call WriteString
43 call Crlf
44 ret
45 upper_case ENDP
46
47 compare_strings PROC ; 比较 str1 和 str2
48 INVOKE Str_compare, ADDR str1, ADDR str2
49 .IF ZERO?
50 mov edx, OFFSET msg1 ; str1 = str2
51 .ELSEIF CARRY?
52 mov edx, OFFSET msg2 ; str1
53 .ELSE
54 mov edx, OFFSET msg3 ; str1 > str2
55 .ENDIF
56 call WriteString
57 call Crlf
58 ret
59 compare_strings ENDP
60
61 print_length PROC ; 获取字符串长度
62 mov edx, OFFSET msg4
63 call WriteString
64 INVOKE Str_length, ADDR str1
65 call WriteDec
66 call Crlf
67 ret
68 print_length ENDP
69
70 END main
abcde////
Trimming: abcde
Upper case: ABCDE
str1 == str2
Length of str1: 5
1 INCLUDE Irvine32.inc
2
3 .data
4 tableB BYTE 10h, 20h, 30h, 40h, 50h ; 数组定义能断开，中间插入一个用于计算数组行宽的常量
5 Rowsize = ($ - tableB)
6 BYTE 60h, 70h, 80h, 90h, 0A0h
7 BYTE 0B0h, 0C0h, 0D0h, 0E0h, 0F0h
8
9 tableW WORD 10h, 20h, 30h, 40h, 50h
10 RowsizeW = ($ - tableW)
11 WORD 60h, 70h, 80h, 90h, 0A0h
12 WORD 0B0h, 0C0h, 0D0h, 0E0h, 0F0h
13
14 tableD DWORD 10000h, 20000h, 30000h, 40000h, 50000h
15 RowSizeD = ($ - tableD)
16 DWORD 60000h, 70000h, 80000h, 90000h, 0A0000h
17 DWORD 0B0000h, 0C0000h, 0D0000h, 0E0000h, 0F0000h
18
19 .code
20 main PROC
21
22 row = 1 ; 目标元素的下标
23 col = 2
24
25 mov ebx, OFFSET tableB ; 指向数组首元素
26 add ebx, RowSize * row ; 计算行偏移
27 mov esi, col ; 列偏移
28 mov al, [ebx + esi] ; 取目标元素
29 call DumpRegs ; AL = 80h
30
31 mov ebx, OFFSET tableW ; 相同的过程
32 add ebx, RowSizeW * row
33 mov esi, col
34 mov ax, [ebx + esi*TYPE tableW] ; 元素不是 BYTE 时要乘以比例因子
35 call DumpRegs ; AX = 0080h
36
37 mov eax, row
38 mov esi, col
39 call get_tableDval ; 使用函数寻找目标元素
40 call WriteHex ; 目标元素在 eax 中
41 call Crlf
42 call WaitMsg
43 exit
44 main ENDP
45
46 get_tableDval PROC uses ebx
47 mov ebx, RowSizeD
48 mul ebx ; eax *= RowSizeD，行偏移
49 mov eax, tableD[eax + esi*TYPE tableD] ; 加上列偏移再寻址
50 ret ; eax = 80000h
51 get_tableDval ENDP
52
53 END main
1 ; BinarySearchTest.asm，测试函数
2 INCLUDE Irvine32.inc
3 INCLUDE BinarySearch.inc
4
5 LOWVAL = -5000
6 HIGHVAL = +5000
7 ARRAY_SIZE = 50
8
9 .data
10 array DWORD ARRAY_SIZE DUP(?)
11
12 .code
13 main PROC
14 call Randomize ; 初始化随机数种子
15 INVOKE FillArray, ADDR array, ARRAY_SIZE, LOWVAL, HIGHVAL ; 用随机数填充数组
16 INVOKE PrintArray, ADDR array, ARRAY_SIZE ; 显示数组内容
17 call WaitMsg
18 call Crlf
19
20 INVOKE BubbleSort, ADDR array, ARRAY_SIZE ; 冒泡排序
21 INVOKE PrintArray, ADDR array, ARRAY_SIZE
22 call WaitMsg
23 call Crlf
24
25 call AskForSearchVal ; 输入待查找的数字
26 INVOKE BinarySearch, ADDR array, ARRAY_SIZE, eax ; 二叉搜索
27 call ShowResults ; 输出搜索结果
28 call WaitMsg
29
30 exit
31 main ENDP
32
33 AskForSearchVal PROC
34 .data
35 prompt BYTE "Signed integer to find: ",0
36 .code
37 call Crlf
38 mov edx, OFFSET prompt
39 call WriteString
40 call ReadInt
41 ret
42 AskForSearchVal ENDP
43
44 ShowResults PROC
45 .data
46 msg1 BYTE "Not found.",0
47 msg2 BYTE "Found at index：",0
48 .code
49 .IF eax == -1
50 mov edx, OFFSET msg1
51 call WriteString
52 .ELSE
53 mov edx, OFFSET msg2
54 call WriteString
55 call WriteDec
56 .ENDIF
57 call Crlf
58 ret
59 ShowResults ENDP
60
61 END main
1 ; FillArray.asm，用 [LowerRange, UpperRange - 1] 之间随机的整数来填充数组
2 INCLUDE Irvine32.inc
3
4 .code
5 FillArray PROC USES eax edi ecx edx, pArray:PTR DWORD, Count:DWORD, LowerRange:SDWORD, UpperRange:SDWORD
6
7 mov edi, pArray
8 mov ecx, Count
9 mov edx, UpperRange
10 sub edx, LowerRange
11 cld ; 清除方向标志位
12
13 L1:
14 mov eax, edx
15 call RandomRange
16 add eax, LowerRange
17 stosd ; eax 的值保存到 [edi]
18 loop L1
19
20 ret
21 FillArray ENDP
22
23 END
1 ; PrintArray.asm，打印数组
2 INCLUDE Irvine32.inc
3
4 .code
5 PrintArray PROC USES eax ecx edx esi, pArray:PTR DWORD, Count:DWORD
6
7 .data
8 comma BYTE ", ",0 ; 逗号
9 .code
10 mov esi, pArray
11 mov ecx, Count
12 cld
13
14 L1:
15 lodsd ; 读取 [ESI] 给 eax
16 call WriteInt
17 mov edx, OFFSET comma
18 call Writestring
19 loop L1
20
21 call Crlf
22 ret
23 PrintArray ENDP
24
25 END
1 ; BubbleSort.asm，冒泡排序
2 INCLUDE Irvine32.inc
3
4 .code
5 BubbleSort PROC USES eax ecx esi, pArray:PTR DWORD, Count:DWORD
6
7 mov ecx, Count
8 dec ecx ; 外层循环 ecx -->0
9
10 L1:
11 push ecx ; 内层循环，保存 ecx
12 mov esi, pArray
13
14 L2:
15 mov eax, [esi] ; 取出相邻两个元素作比较
16 cmp [esi + 4] ,eax
17 jge L3 ; pArray[esi]
18 xchg eax, [esi+4]
19 mov [esi], eax
20
21 L3:
22 add esi, 4 ; 后移一位
23 loop L2
24
25 pop ecx ; 退到外层循环以前恢复 ecx
26 loop L1
27
28 L4:
29 ret
30 BubbleSort ENDP
31
32 END
1 ; BinarySearch.asm，二分搜索
2 INCLUDE Irvine32.inc
3
4 .code
5 BinarySearch PROC USES ebx edx esi edi, pArray:PTR DWORD, Count:DWORD, searchVal:DWORD
6
7 LOCAL first:DWORD, last:DWORD, mid:DWORD
8
9 mov first, 0
10 mov eax, Count
11 dec eax
12 mov last, eax
13 mov edi, searchVal
14 mov ebx, pArray
15
16 L1: ; first
17 mov eax, first
18 cmp eax, last
19 jg L5 ; first > last，退出搜索
20
21 mov eax, last ; 计算 mid
22 add eax, first
23 shr eax, 1
24 mov mid, eax
25
26 mov esi, mid
27 shl esi, 2 ; 下标乘以 4，变成数组偏移量
28 mov edx, [ebx + esi] ; EDX = pArray[mid]
29
30 cmp edx, edi ; 比较 edx 和 查找的值
31 jge L2 ; edx >= searchval 跳转
32 mov eax, mid ; first = mid + 1
33 inc eax
34 mov first, eax
35 jmp L4
36
37 L2:
38 cmp edx,edi ; 比较 edx 和 查找的值
39 jle L3 ; edx
40 mov eax, mid ; last = mid - 1
41 dec eax
42 mov last, eax
43 jmp L4
44
45 L3:
46 mov eax, mid ; edx == searchval
47 jmp L9 ; 返回，eax即为找到的下标
48
49 L4:
50 jmp L1 ; 调整过 first 或 last，继续搜索
51
52 L5:
53 mov eax, -1 ; 没找到
54 L9:
55 ret
56 BinarySearch ENDP
57
58 END
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