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Re: JIT debugging (Attach and speed)
- From: Yichao Yu <yyc1992 at gmail dot com>
- To: Pedro Alves <palves at redhat dot com>
- Cc: gdb at sourceware dot org, Paul Pluzhnikov <ppluzhnikov at google dot com>
- Date: Wed, 23 Mar 2016 16:51:19 -0400
- Subject: Re: JIT debugging (Attach and speed)
- Authentication-results: sourceware.org; auth=none
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On Wed, Mar 23, 2016 at 3:48 PM, Pedro Alves <palves@redhat.com> wrote:
> On 03/23/2016 07:32 PM, Yichao Yu wrote:
>
>>> So, as a quick hack, if you make inline_frame_sniffer bail out early
>>> with 0, does it improve things?
>>
>
>> The timing looks the same. =(
>
> Bummer. :-/
>
> Having now looked at the gdb.base/jit.exp test, I see that
> we can easily reproduce this with:
>
> gdb ---args ./testsuite/outputs/gdb.base/jit/jit-main ./testsuite/outputs/gdb.base/jit/jit-solib.so 2000
>
> (It'd be nice to turn this into a check-perf test...)
The new profile after disabling that line[1].
Am I reading it correctly that it skips the one I disabled and fails
to the next option which is basically as expensive?
Also, it looks like gdb is trying to get info about the current frame?
Can this be disabled for this breakpoint since it's not a "real" one?
[1] http://i.imgur.com/NHdoka8.jpg
>
>> What do you mean by "loader"? since you mentioned call JIT_REGISTER I
>> assume you mean JIT compiler?
>
> Yes, sorry. I meant whatever code ends up "sending" a JIT_REGISTER
> event to gdb.
>
> Thanks,
> Pedro Alves
>