实现在整数的二进制表示中计数“1”的数量

Question

请帮忙！我有一个汇编代码实现，在Microsoft Visual Studio中以整数的二进制表示形式计算“1”的数量。

我实际上可以编译没有错误！但是当我跑步时，我得到了一个未处理的例外：

**'lab2.exe' (Win32): Loaded 'C:\Windows\System32\kernel32.dll'. Cannot find or open the PDB file.
'lab2.exe' (Win32): Loaded 'C:\Windows\System32\KernelBase.dll'. Cannot find or open the PDB file.
'lab2.exe' (Win32): Loaded 'C:\Windows\System32\msvcr120d.dll'. Cannot find or open the PDB file.
First-chance exception at 0x68A07310 (msvcr120d.dll) in lab2.exe: 0xC0000005: Access violation writing location 0x00000000.
Unhandled exception at 0x68A07310 (msvcr120d.dll) in lab2.exe: 0xC0000005: Access violation writing location 0x00000000.
The program '[3356] lab2.exe' has exited with code 0 (0x0).**

我的代码在这里:(

__declspec(naked) unsigned int countOnes(unsigned int x) {
   __asm{
    PUSH EAX
    PUSH EBX
    PUSH ECX
    PUSH EDX

    XOR EAX, EAX
    MOV EBX, [ESP + 20]
    XOR ECX, ECX
    MOV EDX, 1

FOR_LOOP:
    CMP ECX, 8
    JGE END_LOOP

    AND EDX, EBX
    CMP EDX, 1
    JE COUNT

NEXT:
    INC ECX
    XOR EDX, EDX
    SHL EDX, CL
    JMP FOR_LOOP

COUNT:
    INC EAX
    JMP NEXT

END_LOOP:
    ret
}
}