Inline assemble question

[Thrawn]

I need to convert an entire c++ function to use inline assembly.  I'm having trouble figuring out how to access an array of unsigned longs and how to access single characters from a CString.  Any info leading to me being able to do either would be appreciated.
Here's the original code.  I don't want to post the code I've written so far since it's for a class.

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int CCRCfileDlg::Get_CRC(CString &csData, DWORD dwSize) {
   // Be sure to use unsigned variables,
   // because negative values introduce high bits
   // where zero bits are required.
   ULONG  crc(0xffffffff);
   int len;
   unsigned char* buffer;

   len = dwSize;
   // Save the text in the buffer.
   buffer = (unsigned char*)(LPCTSTR)csData;
   // Perform the algorithm on each character
   // in the string, using the lookup table values.
   while(len--)
      crc = (crc >> 8) ^ crc32_table[(crc & 0xFF) ^ *buffer++];
      // Exclusive OR the result with the beginning value.
   return crc^0xffffffff;
}


[EduardoS]

You can simple ask to your compiler generate the asm output, i think he will do something like:

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Get_CRC Proc uses ebx csData:DWORD, dwSize:DWORD
mov ecx, dwSize
mov ebx, csData
or eax, -1
dec ecx
@@:
movzx edx, al
xor cl, [ebx]
shr eax, 8
xor eax, [offset crc32_table+ecx]
inc ebx
sub ecx, 1
jnc @B
not eax
ret

Get_CRC EndP