fastcall调用约定详解（VC与Delphi）
fastcall调用约定
1.函数的前几个参数通过寄存器传递，其他参数通过堆栈.
2.被调用函数清理堆栈
3.函数名修改规则同stdcall
VC中的fastcall.
Add(1,2,3,4,5);
00417B83 push 5
00417B85 push 4
00417B87 push 3
00417B89 mov edx,2
00417B8E mov ecx,1
00417B93 call Add (411749h)
int _fastcall Add(int n1,int n2,int n3,int n4,int n5)
{
00417B10 push ebp
00417B11 mov ebp,esp
00417B13 sub esp,0D8h
00417B19 push ebx
00417B1A push esi
00417B1B push edi
00417B1C push ecx
00417B1D lea edi,[ebp-0D8h]
00417B23 mov ecx,36h
00417B28 mov eax,0CCCCCCCCh
00417B2D rep stos dword ptr es:[edi]
00417B2F pop ecx
00417B30 mov dword ptr [ebp-14h],edx
00417B33 mov dword ptr [ebp-8],ecx
return n1+n2+n3+n4+n5;
00417B36 mov eax,dword ptr [n1]
00417B39 add eax,dword ptr [n2]
00417B3C add eax,dword ptr [n3]
00417B3F add eax,dword ptr [n4]
00417B42 add eax,dword ptr [n5]
}
00417B45 pop edi
00417B46 pop esi
00417B47 pop ebx
00417B48 mov esp,ebp
00417B4A pop ebp
00417B4B ret 0Ch
delphi中的fastcall.
Add(1,2,3,4,5);
00451F91 6A04 push $04
00451F93 6A05 push $05
00451F95 B903000000 mov ecx, $00000003
00451F9A BA02000000 mov edx, $00000002
00451F9F B801000000 mov eax, $00000001
|
00451FA4 E8C7FFFFFF call 00451F70
function Add(n1,n2,n3,n4,n5:Integer):Integer;
demoform.pas.35: begin
00451F70 55 push ebp
00451F71 8BEC mov ebp,esp
demoform.pas.36: Result:=n1+n2+n3+n4+n5;
00451F73 03D0 add edx,eax
00451F75 03CA add ecx,edx
00451F77 034D0C add ecx,[ebp+$0c]
00451F7A 034D08 add ecx,[ebp+$08]
00451F7D 8BC1 mov eax,ecx
demoform.pas.37: end;
00451F7F 5D pop ebp
00451F80 C20800 ret $0008