Symbolic range analysis

[Hongtao Yu]

Hi All,

Does it perform symbolic range analysis or array section analysis in 
GCC-4.6 ?


Thanks,
Hongtao Yu
Purdue University

About new project

[Hongtao Yu]

Hi All,

How can I set up a new project under GCC and make it open-sourced? Thanks!

Cheers,
Hongtao

Re: About new project

[Hongtao Yu]

On 1/27/2013 5:04 PM, Gerald Pfeifer wrote:

On Sat, 26 Jan 2013, Hongtao Yu wrote:

How can I set up a new project under GCC and make it open-sourced?
Thanks!

That depends on what you mean by "under GCC", I'd say.  If you
have improvements for GCC, submitting those as patches against
GCC will be best, cf. http://gcc.gnu.org/contribute.html .

If you want to work on an independent project, you can just go
ahead and use one of those services like github, SourceForge etc.
Actually, we have designed and implement a tentative demand-driven 
flow- and context-sensitive pointer analysis in GCC 4.7. This pointer 
analysis is used for pairwise data dependence checking for 
vectorization. Currently, it does not serve for optimizations directly, 
although it may do in the future. Do you think which way is best for 
releasing our code, to open a branch inside GCC or to release a plugin 
for GCC? Thanks!


Hongtao


(Note that the GNU project talks about free software, cf.
https://www.gnu.org/philosophy/free-software-for-freedom.html )

Gerald

Re: State of AutoFDO in GCC

[Hongtao Yu via Gcc]

Andi, thanks for pointing out the perf script issues. Can you please elaborate 
a bit on the exact issue you have seen? We’ve been using specific output of 
perf script such as mmap, LBR and callstack events filtered by process id. It 
works fine so far but may certainly hit issues in the future with extended uses.

Thanks,
Hongtao

From: Xinliang David Li 
Date: Monday, April 26, 2021 at 11:05 AM
To: Andi Kleen 
Cc: Jan Hubicka , gcc@gcc.gnu.org , Wei Mi 
, Eugene Rozenfeld , Wenlei He 
, Hongtao Yu 
Subject: Re: State of AutoFDO in GCC


On Mon, Apr 26, 2021 at 11:00 AM Andi Kleen 
mailto:a...@linux.intel.com>> wrote:
>There are multiple directional changes in this new tool:
>1) it uses perf-script trace output (in text) as input profile data;

I suspect this will break regularly too

(I personally did numerous changes to perf script output, and also
wrote a lot of parsing scripts)

The perf script output has some bad problems, e.g. for file names or processes
with spaces and some other issues. To make it handleable would need some
redesign to actually generate in a machine friendly format.

Andi, thanks for the input.


+authors of the llvm-profgen tool for their experience with using perf script 
output.

David




A perf.data parser should be fine, just don't fill it up with asserts
and "be liberal what you accept" and ignore unknown records.

-Andi