轉換一個C++內聯彙編函數的德爾福內聯彙編函數

Question

請怎麼會這樣C++函數轉換爲德爾福：

int To_Asm_Fnc(dword Amem, dword Al, dword Ac) { 
int b = 0; 
    asm ("push %%ecx; \ 
      call %%eax; \ 
      pop %%ecx;" 
     : "=Al" (b) /* output value */ 
     : "Al" (mem), "Ac" (Al), "d" (Ac) /* input value */ 
     ); 
    return b; 
} 

，這是我的德爾福嘗試

Function To_Asm_Fnc(Amem,Al,Ac:dword):Integer; 
var 
b:Integer; 
begin 
Result:=0; 
b:=0; 
//******* 
{ i really didn't get it as in the c++ code } 
//******* 
Result:=b; 
end; 

千恩萬謝

Answer 1

看起來這個函數接受指向另一個函數的指針，並設置參數

function To_Asm_Fnc(Amem: Pointer; _Al, _Ac: cardinal): integer; 
asm 
    // x68 only!; paramateres are passed differently in x64 
    // inputs : "Al" (mem), "Ac" (Al), "d" (Ac) /* input value */ 
    // amem is already in eax 
    // _al is passed in edx and _ac in ecx; but the code expects them reversed 
    xchg edx, ecx 
    push ecx 
    call eax 
    pop ecx 
    // result is already in eax and delphi returns the result in eax 
    // outputs : "=Al" (b) /* output value */ 
end;