Re: [Qemu-devel] [Bug 600589] [NEW] xchg r8,rax treated as nop

[vic3dexe]

You wrote 1 июля 2010 г., 19:43:06:

> On Thu, 1 Jul 2010, Richard Henderson wrote:

>> On 07/01/2010 05:04 AM, Vic3Dexe wrote:
>> > Public bug reported:
>> > 
>> > xchg r8,rax (49h 90h) executed as nop (90h) in long mode, in other words
>> > REX not used.
>> > 
>> > qemu 0.12.4, host Win 7 x64,  running qemu-system-x86_64.exe.
>> > 
>> > ** Affects: qemu
>> >      Importance: Undecided
>> >          Status: New
>> > 
>> 
>> Verified.  Test case for x86_64-linux-user:
>> 
>>       .globl  main
>>       .type   main, @function
>> main:
>>       movl    $0, %r8d
>>       movl    $1, %eax
>>       xchgq   %r8, %rax
>>       ret
>> 
>> Expected result is exit status 0.
>> 

> No surprise really:

> target-i386/translate.c lines 6665-...

>     case 0x90: /* nop */
>         /* XXX: xchg + rex handling */
>         /* XXX: correct lock test for all insn */

> The code to handle that just isn't there.

Sorry for inconvenience, I just forgot to look in source. :)
Do you plan to fix it in the near future?

-- 
Best regards,
 Vic3dexe                          mailto:address@hidden