Re: gdb reverse debugging error

[paawan oza <paawan1982 at yahoo dot com>]

Thats amazing : )

by the way
If you can throw some pointers for below things it would be great.
This is regarding porting reversible stuff on ARM.

Hi,

-> latest datasheet, in order to get, requires registration to from ARM 

-> need to contact qemu guys to get arm target. (qemu part is difficult to setup)

I am not sure, how to go about above two things, assuming that there are no alternatives.

PS: both are very important points as having right spec and target, will end up doing right coding.

above points came up because of following with Sean Chen's answers.

1) which Arm family/data sheet need to be refereed ?

DDI0100I_ARM_Architecture_Reference_Manual and DDI0308C_thumb2_supplement are the latest basic documents. To
implement coprocessor instructions which is a plus such as VPF, NEON and WMMX, you might need the coresponding specs.

2) I am planning to use 'target simulator' command, and cross compiling test programs for arm. so with that simulator I can finish everything except Linux ABI
Arm-elf is a choice. However, I am not sure whether it supports the latest ARMv7 and Thumb2 instructions. I think a real ARM target or
QEMU is necessary, otherwise, it's very inconvenient for you to test and implement the Linux function call handler. 

3) and at the last step I will be trying to get arm kernel and finish linux ABI part. You will need  real ARM target or QEMU absolutely.
PS : some way it is getting difficult to use qemu or other virtual emulation and fit it on to x86 emulating ARM. QEMU is a good choice if you don't have any ARM target. You might need to contact QEMU guys.

Regards,
Oza.



----- Original Message ----
From: Hui Zhu <teawater@gmail.com>
To: paawan oza <paawan1982@yahoo.com>
Cc: hefeweizen <horacio.sanchez@kit.edu>; gdb@sourceware.org
Sent: Tue, March 30, 2010 12:33:02 PM
Subject: Re: gdb reverse debugging error

See the title of this link.  :)

Hui

On Tue, Mar 30, 2010 at 15:01, paawan oza <paawan1982@yahoo.com> wrote:
> so does it support
> XMM, SSE and MMX insn support for x86 also ?
> regards,
> Oza.
>
>
> ----- Original Message ----
> From: Hui Zhu <teawater@gmail.com>
> To: hefeweizen <horacio.sanchez@kit.edu>
> Cc: gdb@sourceware.org
> Sent: Tue, March 30, 2010 12:25:36 PM
> Subject: Re: gdb reverse debugging error
>
> Hi horacio,
>
> Thanks for you to report us about this issue.
>
> 0f0d is a 3dnow insn, Current gdb(7.1 cvs-head) is still not suport it.
> But we are working on it now, please try the patch in
> http://sourceware.org/ml/gdb-patches/2010-03/msg00944.html if you are
> interesting with it.
>
> Best regards,
> Hui
>
> On Sat, Mar 27, 2010 at 23:29, hefeweizen <horacio.sanchez@kit.edu> wrote:
>>
>>
>>
>> Hi,
>>
>> i started to try reverse debugging with gdb 7, followin the tutorial:
>>
>> http://www.sourceware.org/gdb/wiki/ProcessRecord/Tutorial
>>
>> and I thought, great!
>>
>> Then I started to debug a real program which gives an error at the end. So I
>> run it with gdb, and I put a breakpoint just before the place I think the
>> error appears. Then I type "record" in order to start to recrd actions for
>> future reverse-debugging. But after some steps I get
>>
>> Process record doesn't support instruction 0xf0d at address 0x2aaaab4c4b4e.
>> Process record: failed to record execution log.
>>
>> Program received signal SIGTRAP, Trace/breakpoint trap.
>> 0x00002aaaab4c4b4e in memcpy () from /lib64/libc.so.6
>> (gdb) n
>> Single stepping until exit from function memcpy,
>> which has no line number information.
>> Process record doesn't support instruction 0xf0d at address 0x2aaaab4c4b4e.
>> Process record: failed to record execution log.
>>
>> Program received signal SIGABRT, Aborted.
>> 0x00002aaaab4c4b4e in memcpy () from /lib64/libc.so.6
>>
>> Before I look at in in detail, I wonder if this feature is still buggy, or
>> if I should start to record from the beginning.
>>
>> Where this "record" error happens, just an object is created as a copy of
>> other:
>>
>> Thanks
>>
>> --
>> View this message in context: http://old.nabble.com/gdb-reverse-debugging-error-tp28053097p28053097.html
>> Sent from the Sourceware - gdb list mailing list archive at Nabble.com.
>>
>>
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