* [Qemu-devel] regs_to_env() ?
@ 2010-07-22 2:06 Jun Koi
2010-07-22 22:08 ` Blue Swirl
0 siblings, 1 reply; 4+ messages in thread
From: Jun Koi @ 2010-07-22 2:06 UTC (permalink / raw)
To: qemu-devel
Hi,
Function regs_to_env() in target-i386/exec.h has a code like below:
...
#ifdef reg_EAX
env->regs[R_EAX] = EAX
#endif
...
However, elsewhere we have EAX defined as:
#define EAX (env->regs[R_EAX])
This means effectively, we have code like:
env->regs[R_EAX] = env->regs[R_EAX];
What is the meaning of this code? That looks pointless to me, but I
guess I must be wrong here...
Thanks,
Jun
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] regs_to_env() ?
2010-07-22 2:06 [Qemu-devel] regs_to_env() ? Jun Koi
@ 2010-07-22 22:08 ` Blue Swirl
2010-07-23 1:43 ` Jun Koi
0 siblings, 1 reply; 4+ messages in thread
From: Blue Swirl @ 2010-07-22 22:08 UTC (permalink / raw)
To: Jun Koi; +Cc: qemu-devel
On Thu, Jul 22, 2010 at 2:06 AM, Jun Koi <junkoi2004@gmail.com> wrote:
> Hi,
>
> Function regs_to_env() in target-i386/exec.h has a code like below:
>
> ...
> #ifdef reg_EAX
> env->regs[R_EAX] = EAX
> #endif
> ...
>
> However, elsewhere we have EAX defined as:
>
> #define EAX (env->regs[R_EAX])
>
> This means effectively, we have code like:
>
> env->regs[R_EAX] = env->regs[R_EAX];
>
> What is the meaning of this code? That looks pointless to me, but I
> guess I must be wrong here...
Yes, those lines don't exist anymore, they were used before TCG. IIRC
EAX was defined to AREG1 etc.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] regs_to_env() ?
2010-07-22 22:08 ` Blue Swirl
@ 2010-07-23 1:43 ` Jun Koi
2010-07-23 1:51 ` Jun Koi
0 siblings, 1 reply; 4+ messages in thread
From: Jun Koi @ 2010-07-23 1:43 UTC (permalink / raw)
To: Blue Swirl; +Cc: qemu-devel
On Fri, Jul 23, 2010 at 7:08 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
> On Thu, Jul 22, 2010 at 2:06 AM, Jun Koi <junkoi2004@gmail.com> wrote:
>> Hi,
>>
>> Function regs_to_env() in target-i386/exec.h has a code like below:
>>
>> ...
>> #ifdef reg_EAX
>> env->regs[R_EAX] = EAX
>> #endif
>> ...
>>
>> However, elsewhere we have EAX defined as:
>>
>> #define EAX (env->regs[R_EAX])
>>
>> This means effectively, we have code like:
>>
>> env->regs[R_EAX] = env->regs[R_EAX];
>>
>> What is the meaning of this code? That looks pointless to me, but I
>> guess I must be wrong here...
>
> Yes, those lines don't exist anymore, they were used before TCG. IIRC
> EAX was defined to AREG1 etc.
>
hey, that sounds funny.
will you take a patch removing both regs_to_env() and env_to_regs() ?
thanks,
J
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] regs_to_env() ?
2010-07-23 1:43 ` Jun Koi
@ 2010-07-23 1:51 ` Jun Koi
0 siblings, 0 replies; 4+ messages in thread
From: Jun Koi @ 2010-07-23 1:51 UTC (permalink / raw)
To: Blue Swirl; +Cc: qemu-devel
On Fri, Jul 23, 2010 at 10:43 AM, Jun Koi <junkoi2004@gmail.com> wrote:
> On Fri, Jul 23, 2010 at 7:08 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>> On Thu, Jul 22, 2010 at 2:06 AM, Jun Koi <junkoi2004@gmail.com> wrote:
>>> Hi,
>>>
>>> Function regs_to_env() in target-i386/exec.h has a code like below:
>>>
>>> ...
>>> #ifdef reg_EAX
>>> env->regs[R_EAX] = EAX
>>> #endif
>>> ...
>>>
>>> However, elsewhere we have EAX defined as:
>>>
>>> #define EAX (env->regs[R_EAX])
>>>
>>> This means effectively, we have code like:
>>>
>>> env->regs[R_EAX] = env->regs[R_EAX];
>>>
>>> What is the meaning of this code? That looks pointless to me, but I
>>> guess I must be wrong here...
>>
>> Yes, those lines don't exist anymore, they were used before TCG. IIRC
>> EAX was defined to AREG1 etc.
>>
>
> hey, that sounds funny.
>
> will you take a patch removing both regs_to_env() and env_to_regs() ?
oops that was removed in latest code already. (i looked at 0.12.4 code)
thanks,
J
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2010-07-23 1:51 UTC | newest]
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2010-07-22 2:06 [Qemu-devel] regs_to_env() ? Jun Koi
2010-07-22 22:08 ` Blue Swirl
2010-07-23 1:43 ` Jun Koi
2010-07-23 1:51 ` Jun Koi
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