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From: Richard Henderson <rth@twiddle.net>
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Date: Fri, 16 Oct 2015 12:14:11 +1100
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Subject: Re: [Qemu-devel] [PATCH] target-*: Advance pc after recognizing a
 breakpoint
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Sergey Fedorov <serge.fdrv@gmail.com>, QEMU Developers <qemu-devel@nongnu.org>

On 10/16/2015 03:36 AM, Peter Maydell wrote:
> On 14 October 2015 at 22:02, Richard Henderson <rth@twiddle.net> wrote:
>> On 10/15/2015 06:34 AM, Peter Maydell wrote:
>>>
>>> This is still the same cryptic comment we have in the
>>> targets which do do this. Can we have something
>>> that is a bit more explanatory about what is going on and
>>> why we need to do this, please?
>>
>>
>> Suggestions?
>
> ...well, I don't entirely understand the problem it's
> fixing, which is why I'm asking for a better comment :-)

Heh.  Fair enough.  How about

   /* The address covered by the breakpoint must be included in
      [tb->pc, tb->pc + tb->size) in order to for it to be
      properly cleared -- thus we increment the PC here so that
      the logic setting tb->size below does the right thing.  */

There are two edge cases that cause the problem with clearing that could be 
described, but I think that the comment becomes too bulky, as well as confuses 
the situation for someone cutting-and-pasting the logic to a new port.


r~