Re: [PATH] AMD MWAITX enablement

["H.J. Lu" <hjl.tools@gmail.com>]

On Fri, Jun 26, 2015 at 9:26 AM, Pawar, Amit <Amit.Pawar@amd.com> wrote:
>
> On Fri, Jun 26, 2015 at 8:00 AM, Pawar, Amit <Amit.Pawar@amd.com> wrote:
>>
>> Comments are fixed and please suggest how to allow following instructions without operands
>>
>> --- Required ----
>> label:
>> monitorx
>> mwaitx
>> --------------------
>>
>> ---- Accepted----
>> monitorx %eax, %ecx, %edx
>> mwaitx %eax, %ecx, %ebx
>> --------------------
>> by adding following code
>>
>> if (i.operands != 3)
>>   abort ();
>>
>>
>> -----Original Message-----
>> From: H.J. Lu [mailto:hjl.tools@gmail.com]
>> Sent: Friday, June 26, 2015 5:26 PM
>> To: Pawar, Amit
>> Cc: binutils@sourceware.org; Jan Beulich
>> Subject: Re: [PATH] AMD MWAITX enablement
>>
>> On Fri, Jun 26, 2015 at 4:09 AM, Pawar, Amit <Amit.Pawar@amd.com> wrote:
>>>
>>> Operand check is required at that line as instructions MONITORX/MWAITX are accepted without operands also.
>>
>> Add
>
> You have
>
> if (i.tm.cpu_flags.bitfield.cpumwaitx && i.operands > 0)
>   {
> ....
>   }
> [Pawar, Amit] This condition was included to handle mwaitx cpu instructions with more than zero
> operands and skips for zero operands.
>
> If i.operands == 0, you won't reach
>>[Pawar, Amit] Zero operands instruction are allowed but should not enter here as it will get
> handled by normal code.
>
> if (i.operands != 3)
>   abort ();
> [Pawar, Amit] Will throw error for zero operand instructions, as this is inside if case and which is
> not required here.

I meant

if (i.tm.cpu_flags.bitfield.cpumwaitx && i.operands > 0)
  {
     if (i.operands != 3)
       abort ();
    ...
  }



-- 
H.J.