Re: GDB MI Reverse Commands added [3 of 3]

[Hui Zhu <teawater@gmail.com>]

On Fri, Sep 4, 2009 at 02:43, Jakob Engblom<jakob@virtutech.com> wrote:
>> The file should be called mi-reverse.exp, I think, because mi2- files are
>> supposed to test
>> that whatever was once announced as MI2 is not broken. And this is new
>> development. Likewise,
>
> Done.
>
>>         set MIFLAGS "-i=mi2"
>>
>> should be:
>>
>>         set MIFLAGS "-i=mi"
>
> Done.
>
>> Also, I would appreciate if this:
>>
>>     # Test exec-reverse-next
>>     # FIXME: Why does it take 2 next commands to get back to the
>>     #        previous line?
>>
>> were somehow addressed. I am not familiar with details of reverse behaviour,
> so I
>> did not even try to check that the tested commands and locations, etc, are
> right.
>
> Since this is tested on top of process record, I think I am not the best person
> to answer... but in general, what tends to happen in reverse in my experience is
> this:
>
> We have lines of code (or instructions)
>
> A
> B
>
> And we stop with a breakpoint in line B.
>
> We are then at the end of B, or in the middle of B, in the execution.
>
> Then, doing reverse one step/instruction/line will move you to the start of B.
>
> And another step/instruction/line moves you to before A was executed.
>
> Does that make sense for process record?


I am not sure.  Let me talk what I think about it.

The instruction is:
A
B

When inferior stop at B by breakpoint of line.
We are in the begin of B.
GDB will show we are in B.

A
<----------- This is inferior at.  PC is point to B.
B

reverse-stepi
We are in the begin of A.
GDB will show we are in A.

<----------- This is inferior at.  PC is point to A.
A
B


Thanks,
Hui