🚀 go-pugleaf

Ed Mulroy [TeamB] wrote:

>Either of these should be close.  I say 'close' because I have not tested 

Definately untested <G>

I would also be tempted to turn off stack frames for this function.

>void __fastcall GetCPUID_1(unsigned int cmd, TRegisters & regs)
>  {
>  _EBX = _ECX = _EDX = 0;

Premature clearing of passed variables.
_fastcall Order( EAX, EDX, ECX, SP[4], SP[8].... )

>  _EDI = reinterpret_cast<unsigned long>(& regs);

	_EDI = _EDX
EDI and EBX not preserved as required
(unless compiler is doing hidden magic)

>  _EAX = cmd;

	NOP, cmd is passed in eax

>  __emit__(0x0F, 0xA2); // insert opcode for GetCpuId
>  regs.EDX = _EDX;
>  regs.ECX = _ECX;
>  regs.EBX = _EBX;
>  regs.EAX = _EAX;
>  }
>
>void __fastcall GetCPUID_2(unsigned int cmd, TRegisters & regs)
>  {
>  __asm {
>    xor edx,edx
>    mov ebx,edx
>    mov ecx,edx
>    mov eax,[cmd]
>    mov edi,esi /* _EDI = (unsigned long) & regs; */

Same issues, plus new one:
Where did esi come from?

>    db 0FH, 0A2H /* opcode for GetCpuId */
>    }
>
>  regs.EDX = _EDX;

Does the compiler "know" that you trounced edx (regs)?

>  regs.ECX = _ECX;
>  regs.EBX = _EBX;
>  regs.EAX = _EAX;
>  }