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《汇编语言 基于x86处理器》第十三章高级语言接口部分的代码 part 1

时间:2018-09-24 21:18:44      阅读:162      评论:0      收藏:0      [点我收藏+]

标签:跳转   地址   model   use   方法   tchar   signed   etc   ffffff   

? 书中第十三章的程序,主要讲了汇编语言和 C/++ 相互调用的方法

● 代码,数组求和的几种优化

 1 int arraySum(int array[], int count)            ; O0
 2 {
 3 010716D0  push        ebp  
 4 010716D1  mov         ebp,esp  
 5 010716D3  sub         esp,0D8h  
 6 010716D9  push        ebx  
 7 010716DA  push        esi  
 8 010716DB  push        edi  
 9 010716DC  lea         edi,[ebp-0D8h]  
10 010716E2  mov         ecx,36h  
11 010716E7  mov         eax,0CCCCCCCCh  
12 010716EC  rep stos    dword ptr es:[edi]        ; 栈顶  
13     int i;
14     int sum = 0;
15 010716EE  mov         dword ptr [sum],0  
16 
17     for (i = 0; i < count; i++)
18 010716F5  mov         dword ptr [i],0  
19 010716FC  jmp         arraySum+37h (01071707h)  ; 跳转循环判断
20 010716FE  mov         eax,dword ptr [i]         ;
21 01071701  add         eax,1                     ; ┣ 取出 i 来加一再放回去
22 01071704  mov         dword ptr [i],eax         ;
23 01071707  mov         eax,dword ptr [i]         ;
24 0107170A  cmp         eax,dword ptr [count]     ; ┣ 循环判断
25 0107170D  jge         arraySum+50h (01071720h)  ;
26         sum += array[i];                        
27 0107170F  mov         eax,dword ptr [i]         ; 循环主体,各变量取出来,加完了 sum 放回去
28 01071712  mov         ecx,dword ptr [array]        
29 01071715  mov         edx,dword ptr [sum]  
30 01071718  add         edx,dword ptr [ecx+eax*4]  
31 0107171B  mov         dword ptr [sum],edx  
32 0107171E  jmp         arraySum+2Eh (010716FEh)  
33 
34     return sum;
35 01071720  mov         eax,dword ptr [sum]       ; 返回值放入 eax
36 }
37 01071723  pop         edi  
38 01071724  pop         esi  
39 01071725  pop         ebx  
40 01071726  mov         esp,ebp  
41 01071728  pop         ebp  
42 01071729  ret 
 1 int arraySum(int array[], int count)            ; O1
 2 {
 3 00E51743  push        ebp                       ; 优化了寄存器和栈
 4 00E51744  mov         ebp,esp  
 5     int i;
 6     int sum = 0;
 7 00E51746  xor         eax,eax  
 8 00E51748  mov         ecx,eax                   ; ecx 存储 i
 9 
10     for (i = 0; i < count; i++)
11 00E5174A  cmp         dword ptr [count],eax     ; ┳ 数组长 <0 则退出  
12 00E5174D  jle         arraySum+18h (0E5175Bh)   ;
13 00E5174F  mov         edx,dword ptr [array]     ;
14         sum += array[i];                        ; ┣ 循环主体
15 00E51752  add         eax,dword ptr [edx+ecx*4] ;
16 00E51755  inc         ecx                       ;
17 00E51756  cmp         ecx,dword ptr [count]     ; ┣ i++ 和循环判断  
18 00E51759  jl          arraySum+0Fh (0E51752h)   ;
19 
20     return sum;
21 }
22 00E5175B  pop         ebp  
23 00E5175C  ret  
24     int array[10] = { 1,2,3,4,5,6,7,8,9,10 };   ; 主函数的部分
25 
26     int sum = arraySum(array, 10);
27     return 0;
28     00E5175D  xor         eax,eax 
29 }
30 00E5175F  ret
 1 int arraySum(int array[], int count)            ; O2 / Ox,用了XMM,没啃完
 2 {
 3 000E1760  push        ebp  
 4 000E1761  mov         ebp,esp  
 5 000E1763  push        ecx  
 6 
 7     for (i = 0; i < count; i++)
 8 000E1764  mov         edx,dword ptr [array]  
 9 000E1767  xor         ecx,ecx  
10 000E1769  push        ebx  
11 000E176A  push        esi  
12 000E176B  mov         esi,dword ptr [count]  
13 000E176E  xor         eax,eax  
14 000E1770  mov         dword ptr [ebp-4],ecx  
15 000E1773  push        edi  
16 000E1774  test        esi,esi  
17 000E1776  jle         arraySum+7Bh (0E17DBh)  
18 000E1778  cmp         esi,8  
19 000E177B  jb          arraySum+7Bh (0E17DBh)  
20     int i;
21     int sum = 0;
22 000E177D  mov         ecx,esi  
23 000E177F  and         ecx,80000007h  
24 000E1785  jns         arraySum+2Ch (0E178Ch)  
25 000E1787  dec         ecx  
26 000E1788  or          ecx,0FFFFFFF8h  
27 000E178B  inc         ecx  
28 000E178C  mov         edi,esi  
29 000E178E  xorps       xmm2,xmm2  
30 000E1791  sub         edi,ecx  
31 000E1793  xorps       xmm1,xmm1  
32 000E1796  nop         word ptr [eax+eax]  
33         sum += array[i];
34 000E17A0  movups      xmm0,xmmword ptr [edx+eax*4]  
35 000E17A4  paddd       xmm2,xmm0  
36 000E17A8  movups      xmm0,xmmword ptr [edx+eax*4+10h]  
37 000E17AD  add         eax,8  
38 000E17B0  paddd       xmm1,xmm0  
39 000E17B4  cmp         eax,edi  
40 000E17B6  jl          arraySum+40h (0E17A0h)  
41     int i;
42     int sum = 0;
43 000E17B8  paddd       xmm1,xmm2  
44 000E17BC  movaps      xmm0,xmm1  
45 000E17BF  psrldq      xmm0,8  
46 000E17C4  paddd       xmm1,xmm0  
47 000E17C8  movups      xmm0,xmm1  
48 000E17CB  psrldq      xmm0,4  
49 000E17D0  paddd       xmm1,xmm0  
50 000E17D4  movd        ecx,xmm1  
51 000E17D8  mov         dword ptr [sum],ecx  
52 
53     for (i = 0; i < count; i++)
54 000E17DB  xor         edi,edi  
55 000E17DD  xor         ebx,ebx  
56 000E17DF  cmp         eax,esi  
57 000E17E1  jge         arraySum+0B4h (0E1814h)  
58 000E17E3  mov         ecx,esi  
59 000E17E5  sub         ecx,eax  
60 000E17E7  cmp         ecx,2  
61 000E17EA  jl          arraySum+9Eh (0E17FEh)  
62 000E17EC  lea         ecx,[esi-1]  
63 000E17EF  nop  
64         sum += array[i];
65 000E17F0  add         edi,dword ptr [edx+eax*4]  
66 000E17F3  add         ebx,dword ptr [edx+eax*4+4]  
67 000E17F7  add         eax,2  
68 000E17FA  cmp         eax,ecx  
69 000E17FC  jl          arraySum+90h (0E17F0h)  
70 
71     for (i = 0; i < count; i++)
72 000E17FE  cmp         eax,esi  
73         sum += array[i];
74 000E1800  mov         esi,dword ptr [sum]  
75 000E1803  jge         arraySum+0A8h (0E1808h)  
76 000E1805  add         esi,dword ptr [edx+eax*4]  
77 000E1808  lea         eax,[ebx+edi]  
78 000E180B  pop         edi  
79 000E180C  add         eax,esi  
80 
81     return sum;
82 }
83 000E180E  pop         esi  
84 000E180F  pop         ebx  
85 000E1810  mov         esp,ebp  
86 000E1812  pop         ebp  
87 000E1813  ret  
88 000E1814  pop         edi  
89 000E1815  pop         esi  
90 000E1816  mov         eax,ecx  
91 000E1818  pop         ebx  
92 000E1819  mov         esp,ebp  
93 000E181B  pop         ebp  
94 000E181C  ret 

● C 内嵌汇编(代码段),检查对象大小

 1 #include <iostream>
 2 
 3 #pragma warning (disable:4101)  // 关闭警告 "unreferenced local variables"
 4 
 5 int main()
 6 {
 7     struct Package
 8     {
 9         int     intInStruct;            // 4        
10         float   floatInStruct;          // 4
11         long    doubleInStruct;         // 4
12     } myPackage;
13 
14     char        myChar;
15     bool        myBool;
16     short       myShort;
17     int         myInt;
18     long        myLong;
19     float       myFloat;
20     double      myDouble;
21     long double myLongDouble;
22     long        myLongArray[10];
23 
24     __asm                               // 内联汇编代码
25     {
26         mov  eax, myPackage.doubleInStruct;// 地址
27 
28         mov  eax, LENGTH myInt;         // 1
29         mov  eax, LENGTH myLongArray;   // 10
30 
31         mov  eax, TYPE myChar;          // 1
32         mov  eax, TYPE myBool;          // 1
33         mov  eax, TYPE myShort;         // 2
34         mov  eax, TYPE myInt;           // 4
35         mov  eax, TYPE myLong;          // 4
36         mov  eax, TYPE myFloat;         // 4
37         mov  eax, TYPE myDouble;        // 8        
38         mov  eax, TYPE myLongDouble;    // 8
39 
40         mov  eax, TYPE myPackage;       // 12
41         mov  eax, TYPE myLongArray;     // 4
42 
43         mov  eax, LENGTH myPackage;     // 1
44         mov  eax, LENGTH myLongArray;   // 10
45 
46         mov  eax, SIZE myPackage;       // 12,SIZE 返回 LENGTH * TYPE
47         mov  eax, SIZE myLongArray;     // 40
48     }
49     return 0;
50 }

● C++ 内嵌汇编(单独的函数),加密字符串

 1 #include <iostream>
 2 #include <string>
 3 
 4 using namespace std; 
 5 
 6 void TranslateBuffer(char * buf, unsigned count, unsigned char eChar)
 7 {
 8     __asm
 9     {
10         mov esi, buf    // esi 指向待处理的内存
11         mov ecx, count
12         mov al, eChar
13     L1:
14         xor[esi], al
15         inc  esi
16         Loop L1
17     }
18 }
19 
20 int main(int argcount, char * args[])
21 {
22     string buffer;
23     unsigned char encryptCode;
24 
25     cout << "Input the string:\n\t";            // 需要加密的字符串
26     cin >> buffer;           
27     cout << "\nEncryption code [0-255]?\n\t";   // 秘钥
28     cin >> encryptCode;
29    
30     TranslateBuffer(&buffer[0], buffer.length(), encryptCode);
31    
32     cout << "Output:\n\t" << buffer;
33     getchar();
34     getchar();
35     return 0;
36 }

● C++ 内嵌汇编(独立文件),线性查找。要点:单独使用 ml.exe 编译 index2.asm 生成 index2.obj,在工程中添加为资源文件。输出结果:没开优化,效率奇低(C++ 7193 ms,ASM 34852 ms)

1 // index.h
2 extern "C"
3 {
4     long index( long n, unsigned array[], unsigned count);
5     long index2(long n, unsigned array[], unsigned count);
6 }
 1 // index.cpp
 2 #include "index.h"
 3 
 4 long index(long searchVal, unsigned array[], unsigned count)
 5 {
 6     for (unsigned i = 0; i < count; i++)
 7     {
 8         if (array[i] == searchVal)
 9             return i;
10     }
11     return -1;
12 }
 1 ; index2.asm
 2 .586
 3 .model flat, C
 4 index2 PROTO, srchVal:DWORD, arrayPtr:PTR DWORD, count:DWORD
 5 
 6 .code
 7 
 8 index2 PROC uses ecx esi edi, srchVal:DWORD, arrayPtr:PTR DWORD, count:DWORD
 9     NOT_FOUND = -1
10 
11     mov     eax, srchVal    ; 目标值        
12     mov     ecx, count              
13     mov     esi, arrayPtr
14     mov     edi, 0          ; 数组下标
15 
16 L1: 
17     cmp     [esi + edi * 4], eax
18     je      found
19     inc     edi
20     loop L1
21 
22 notFound:    
23      mov    eax, NOT_FOUND
24      jmp    short exit
25 
26 found:
27      mov    eax, edi
28 
29 exit:
30      ret
31 index2 ENDP
32 END
 1 // main.cpp
 2 #include <iostream>
 3 #include <time.h>
 4 #include "index.h"
 5 
 6 using namespace std;
 7 
 8 int main()
 9 {    
10     const unsigned ARRAY_SIZE = 100000, LOOP_SIZE = 1000000;    // 数组大小和重复次数
11     const unsigned searchVal = rand();
12     clock_t startTime, endTime;
13     unsigned array[ARRAY_SIZE];
14     long count = 0;
15 
16     for (unsigned i = 0; i < ARRAY_SIZE; i++)
17         array[i] = rand();
18 
19     startTime = clock();                                        // 分别使用 C++ 和 ASM 计算同一个函数
20     for (unsigned loop = 0; loop < LOOP_SIZE; loop++)
21         count = index(searchVal, array, ARRAY_SIZE);
22     endTime = clock();
23     cout << "Elapsed time: " << endTime - startTime << " ms, " << ((count == -1) ? "not" : "") << "found" << endl;
24 
25     startTime = clock();
26     for (unsigned loop = 0; loop < LOOP_SIZE; loop++)
27         count = index2(searchVal, array, ARRAY_SIZE);
28     endTime = clock();
29     cout << "Elapsed time: " << endTime - startTime << " ms, " << ((count == -1) ? "not" : "") << "found" << endl;
30 
31     getchar();
32     return 0;
33 }

 

《汇编语言 基于x86处理器》第十三章高级语言接口部分的代码 part 1

标签:跳转   地址   model   use   方法   tchar   signed   etc   ffffff   

原文地址:https://www.cnblogs.com/cuancuancuanhao/p/9696495.html

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