Chuck Ebbert wrote:
>
>> +/* Some CPUID calls want 'count' to be placed in ecx */
>> +static inline void cpuid_count(int op, int count, int *eax, int *ebx, int *ecx,
>> + int *edx)
>> +{
>> + asm volatile(""::"c"(count));
>> + vmi_cpuid(op, eax, ebx, ecx, edx);
>> +}
>>
>
> You can't assume those last two statements will stay together.
> >From the gcc 4.0.2 info file:
>
I know. I've abused this a bit. When we originally wrote the cpuid
call, there were no ecx dependencies on cpuid. Never got around to
fixing it properly.
>
>> <...> you can't expect a sequence of volatile `asm' instructions
>> to remain perfectly consecutive. If you want consecutive output, use a
>> single `asm'.
>>
>
> Maybe you could make vmi_cpuid always take a 'count' param, then just make cpuid
> do:
>
> vmi_cpuid(op, 0, eax, ebx, ecx, edx);
>
> and cpuid_count do:
>
> vmi_cpuid(op, count, eax, ebx, ecx, edx);
>
That is the proper fix. I'll put that in the next round.
>
> (And sorry about trimming the cc: but I'm reading from a digest and that list
> is too long to enter manually.)
>
N.P.
Thanks for looking at my code,
Zach
