qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [4875] Remove unintended dereference, kills a warning (


From: Laurent Desnogues
Subject: Re: [Qemu-devel] [4875] Remove unintended dereference, kills a warning (Jan Kiszka).
Date: Wed, 16 Jul 2008 14:30:08 +0200

On Wed, Jul 16, 2008 at 2:04 PM, Andreas Schwab <address@hidden> wrote:
> Andrzej Zaborowski <address@hidden> writes:
>
>>  void OPPROTO op_tasb_rN(void)
>>  {
>> -    cond_t(*(int8_t *) env->gregs[PARAM1] == 0);
>> -    *(int8_t *) env->gregs[PARAM1] |= 0x80;
>> +    cond_t((env->gregs[PARAM1] && 0xff) == 0);
>> +    *(int8_t *) &env->gregs[PARAM1] |= 0x80;
>
> That does not make any sense at all.  The TAS insn operates on memory,
> not on a register (atomic operations only make sense on memory anyway).

SH4 documentation says this:

TAS.B @Rn
          If (Rn) = 0, 1 → T, else 0 → T
          1 → MSB of (Rn)

So indeed it looks like Jan and Andrzej patch is wrong.


Laurent




reply via email to

[Prev in Thread] Current Thread [Next in Thread]