SWITCH语句(跳转表的结构)

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--- e:/program/test/main.cpp -----------------------------------------------------------------------------------------------------------------------------

1: #include <iostream>

2: using namespace std;

5: int main()

6: {

00401600 push ebp

00401601 mov ebp,esp

00401603 sub esp,54h

00401606 push ebx

00401607 push esi

00401608 push edi

00401609 lea edi,[ebp-54h]

0040160C mov ecx,15h

00401611 mov eax,0CCCCCCCCh

00401616 rep stos dword ptr [edi]

7: int operand;

8: int a=3, b=2;

00401618 mov dword ptr [ebp-8],3

0040161F mov dword ptr [ebp-0Ch],2

9: int result;

10: cin>>operand;

00401626 lea eax,[ebp-4]

00401629 push eax

0040162A mov ecx,offset std::cin (00477878)

0040162F call @ILT+535(std::basic_istream<char,std::char_traits<char> >::operator>>) (0040121c)

11: switch(operand)

12: {

00401634 mov ecx,dword ptr [ebp-4]

00401637 mov dword ptr [ebp-14h],ecx

0040163A cmp dword ptr [ebp-14h],8 SWITCH语句的特征

0040163E ja $L7394+0Ch (004016c7)

00401644 mov edx,dword ptr [ebp-14h]

00401647 jmp dword ptr [edx*4+4016DAh]跳转表基地址

13: case 0:

14: result=a+b;

0040164E mov eax,dword ptr [ebp-8]

00401651 add eax,dword ptr [ebp-0Ch]

00401654 mov dword ptr [ebp-10h],eax

15: break;

00401657 jmp $L7394+0Ch (004016c7)

16: case 1:

17: result=2*a+b;

00401659 mov ecx,dword ptr [ebp-8]

0040165C mov edx,dword ptr [ebp-0Ch]

0040165F lea eax,[edx+ecx*2]

00401662 mov dword ptr [ebp-10h],eax

18: break;

00401665 jmp $L7394+0Ch (004016c7)

19: case 2:

20: result=3*a+b;

00401667 mov ecx,dword ptr [ebp-8]

0040166A imul ecx,ecx,3

0040166D add ecx,dword ptr [ebp-0Ch]

00401670 mov dword ptr [ebp-10h],ecx

21: break;

00401673 jmp $L7394+0Ch (004016c7)

22: case 3:

23: result=4*a+b;

00401675 mov edx,dword ptr [ebp-8]

00401678 mov eax,dword ptr [ebp-0Ch]

0040167B lea ecx,[eax+edx*4]

0040167E mov dword ptr [ebp-10h],ecx

24: break;

00401681 jmp $L7394+0Ch (004016c7)

25: case 4:

26: result=5*a+b;

00401683 mov edx,dword ptr [ebp-8]

00401686 imul edx,edx,5

00401689 add edx,dword ptr [ebp-0Ch]

0040168C mov dword ptr [ebp-10h],edx

27: break;

0040168F jmp $L7394+0Ch (004016c7)

28: case 5:

29: result=6*a+b;

00401691 mov eax,dword ptr [ebp-8]

00401694 imul eax,eax,6

00401697 add eax,dword ptr [ebp-0Ch]

0040169A mov dword ptr [ebp-10h],eax

30: break;

0040169D jmp $L7394+0Ch (004016c7)

31: case 6:

32: result=7*a+b;

0040169F mov ecx,dword ptr [ebp-8]

004016A2 imul ecx,ecx,7

004016A5 add ecx,dword ptr [ebp-0Ch]

004016A8 mov dword ptr [ebp-10h],ecx

33: break;

004016AB jmp $L7394+0Ch (004016c7)

34: case 7:

35: result=8*a+b;

004016AD mov edx,dword ptr [ebp-8]

004016B0 mov eax,dword ptr [ebp-0Ch]

004016B3 lea ecx,[eax+edx*8]

004016B6 mov dword ptr [ebp-10h],ecx

36: break;

004016B9 jmp $L7394+0Ch (004016c7)

37: case 8:

38: result=9*a+b;

004016BB mov edx,dword ptr [ebp-8]

004016BE imul edx,edx,9

004016C1 add edx,dword ptr [ebp-0Ch]

004016C4 mov dword ptr [ebp-10h],edx

39: break;

40: default:

41:

42: break;

43:

44: }

45:

46: return 0;

004016C7 xor eax,eax

47: }

004016C9 pop edi

004016CA pop esi

004016CB pop ebx

004016CC add esp,54h

004016CF cmp ebp,esp

004016D1 call __chkesp (00420cd0)

004016D6 mov esp,ebp

004016D8 pop ebp

004016D9 ret

004016DA dec esi

004016DB push ss

004016DC inc eax

004016DD add byte ptr [ecx+16h],bl

004016E0 inc eax

004016E1 add byte ptr [edi+16h],ah

004016E4 inc eax

004016E5 add byte ptr [ebp+16h],dh

004016E8 inc eax

004016E9 add byte ptr [ebx-6EFFBFEAh],al

004016EF push ss

004016F0 inc eax

004016F1 add byte ptr [edi-52FFBFEAh],bl

004016F7 push ss

004016F8 inc eax

004016F9 add byte ptr [ebx-33FFBFEAh],bh

--- No source file ----------------------------------

内存跳转表数据

004016DA 4E 16 40 00 59 16 40 00 67 16 40 00 75 16 40 00 N.@.Y.@.g.@.u.@.

004016EA 83 16 40 00 91 16 40 00 9F 16 40 00 AD 16 40 00 ..@...@...@...@.

004016FA BB 16 40 00 CC CC CC CC CC CC CC CC CC CC CC CC