Displaying 20 results from an estimated 10000 matches similar to: "RFC: Hotness thresholds in profile header"
2015 Dec 17
2
RFC: Hotness thresholds in profile header
On Wed, Dec 16, 2015 at 6:00 PM, Andy Ayers <andya at microsoft.com> wrote:
> I’ve done similar rankings with profile data and found it worked out pretty
> well.
>
>
>
> In my case it was ranking function hotness but the idea was similar: sort by
> weight, compute various percentile cutoff points, and use those to classify.
> I put in some compensation for truly
2015 Dec 17
2
RFC: Hotness thresholds in profile header
On Thu, Dec 17, 2015 at 9:21 AM, Andy Ayers <andya at microsoft.com> wrote:
> While your bb count distribution is extremely likely to be some kind of power-law like distribution, it's not guaranteed.
>
> Also you might think about operations that can amplify (rerolling) or appear to amplify (TRE) or diminish BB counts, and how you'd go about reclassifying block hotness.
yes
2015 May 28
1
[LLVMdev] Capabilities of Clang's PGO (e.g. improving code density)
On Thu, May 28, 2015 at 9:56 AM, Philip Reames
<listmail at philipreames.com> wrote:
>
>
> On 05/27/2015 11:13 AM, Duncan P. N. Exon Smith wrote:
>>>
>>> On 2015 May 27, at 07:42, Diego Novillo <dnovillo at google.com> wrote:
>>>
>>> On Tue, May 26, 2015 at 11:47 PM, Lee Hunt <leehu at exchange.microsoft.com>
>>> wrote:
2020 Oct 01
3
How to get the loop hotness data in a suite ?
Hi everybody,
I'm trying to get loop hotness data across a suite (e.g. the llvm
test-suite). Ideally,
this would be a list that for each loop would list how many times it was
entered and what
was its iteration count (at least the latter). The closest thing I could
come up with is:
- clang -fprofile-instr-generate (without opts) to get a .profraw
- Get the .profdata
- Give that back to clang
2017 Oct 03
2
PGO information at LTO/thinLTO link step
Thanks Easwaran. This is what we've observed as well, where the old PM
inliner was only looking hot/cold callee information, which have
signficantly smaller boosts/penalties compared to callsite information.
Teresa, do you know if there is some documentation/video/presentation on
how PGO information is represented in LLVM and what information is passed
via the IR? I'm finding some
2017 Oct 03
2
PGO information at LTO/thinLTO link step
On Tue, Oct 3, 2017 at 1:46 PM, Teresa Johnson via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
>
>
> On Tue, Oct 3, 2017 at 1:38 PM, Graham Yiu <gyiu at ca.ibm.com> wrote:
>
>> Hi Teresa,
>>
>> Actually, enabling the new pass manager manually seems to have solved
>> this issue, so this problem is only valid for the old pass manager.
>>
>
2016 Sep 02
3
[ThinLTO] Importing based on PGO data
On Fri, Sep 2, 2016 at 3:30 PM, Xinliang David Li <davidxl at google.com>
wrote:
> On Fri, Sep 2, 2016 at 3:16 PM, Piotr Padlewski
> <piotr.padlewski at gmail.com> wrote:
> >
> >
> > 2016-09-02 15:04 GMT-07:00 Xinliang David Li <davidxl at google.com>:
> >>
> >> On Fri, Sep 2, 2016 at 2:58 PM, Piotr Padlewski
> >>
2017 Dec 13
5
RFC: Synthetic function entry counts
Functions in LLVM IR have a function_entry_count metadata that is attached
in PGO compilation. By using the entry count together with the block
frequency info, the compiler computes the profile count of call
instructions based on which the hotness/coldness of callsites can be
determined. Experiments have shown that using a higher threshold for hot
callsites results in improved runtime performance
2015 Dec 07
4
[LLVMdev] Path forward on profile guided inlining?
(Resending after removing llvmdev at cs.uiuc.edu and using
llvm-dev at lists.llvm.org)
On Mon, Dec 7, 2015 at 3:08 PM, Easwaran Raman <eraman at google.com> wrote:
> Hi Philip,
>
> Is there any update on this? I've been sending patches to get rid of the
> callee hotness based inline hints from the frontend and move the logic to
> the inliner. The next step is to use
2017 Dec 15
2
RFC: Synthetic function entry counts
On Fri, Dec 15, 2017 at 11:56 AM, Sean Silva <chisophugis at gmail.com> wrote:
>
>
> On Fri, Dec 15, 2017 at 11:27 AM, Xinliang David Li <davidxl at google.com>
> wrote:
>
>>
>>
>> On Fri, Dec 15, 2017 at 11:13 AM, Sean Silva <chisophugis at gmail.com>
>> wrote:
>>
>>>
>>>
>>> On Fri, Dec 15, 2017 at 10:22
2017 Dec 15
2
RFC: Synthetic function entry counts
On Fri, Dec 15, 2017 at 11:13 AM, Sean Silva <chisophugis at gmail.com> wrote:
>
>
> On Fri, Dec 15, 2017 at 10:22 AM, Easwaran Raman <eraman at google.com>
> wrote:
>
>>
>>
>> On Fri, Dec 15, 2017 at 12:22 AM, Sean Silva <chisophugis at gmail.com>
>> wrote:
>>
>>> IIUC, this proposal is just saying that we should infer a
2017 Dec 15
2
RFC: Synthetic function entry counts
On Fri, Dec 15, 2017 at 12:22 AM, Sean Silva <chisophugis at gmail.com> wrote:
> IIUC, this proposal is just saying that we should infer a static profile
> for entry counts just like we do for branch probabilities. In the case of
> entry counts, we do not hide that information behind an analysis like BPI,
> so currently just annotating synthetic PGO entry counts is a simple
>
2015 May 28
0
[LLVMdev] Capabilities of Clang's PGO (e.g. improving code density)
On 05/27/2015 11:13 AM, Duncan P. N. Exon Smith wrote:
>> On 2015 May 27, at 07:42, Diego Novillo <dnovillo at google.com> wrote:
>>
>> On Tue, May 26, 2015 at 11:47 PM, Lee Hunt <leehu at exchange.microsoft.com> wrote:
>>
>>> For example, from reading different pages on how Clang PGO, it’s unclear if
>>> it does “block reordering” (i.e. moving
2015 Dec 11
5
[LLVMdev] Path forward on profile guided inlining?
On Thu, Dec 10, 2015 at 4:51 PM, Philip Reames
<listmail at philipreames.com> wrote:
>
>
> On 12/10/2015 04:29 PM, Xinliang David Li wrote:
>>
>> On Thu, Dec 10, 2015 at 4:00 PM, Philip Reames
>> <listmail at philipreames.com> wrote:
>>>
>>> Given I didn't get any response to my original query, I chose not to
>>> invest
2016 May 11
2
Filter optimization remarks by the hotness of the code region
Hi Hal,
> On May 10, 2016, at 5:39 PM, Hal Finkel <hfinkel at anl.gov> wrote:
>
> Hi Adam,
>
> I think would be a really useful feature to have. I don't think that the backend should be responsible for filtering, but should pass the relative hotness information to the frontend. Given that these diagnostics are not just going to be used for -Rpass and friends, but also
2016 Sep 02
2
[ThinLTO] Importing based on PGO data
The profile summary is saved in the global metadata ASAIK. If we want to
calculate if something is hot/cold while choosing functions for importing,
we would either need to read whole Module (which we clearly don't want to
do)
or duplicate this information in the summary, so we could get it without
reading Module.
2016-09-02 15:49 GMT-07:00 Mehdi Amini <mehdi.amini at apple.com>:
>
2015 Dec 11
2
[LLVMdev] Path forward on profile guided inlining?
On Thu, Dec 10, 2015 at 4:00 PM, Philip Reames
<listmail at philipreames.com> wrote:
> Given I didn't get any response to my original query, I chose not to invest
> time in this at the time. I am unlikely to get time for this in the near
> future.
>
> On 12/07/2015 03:13 PM, Easwaran Raman wrote:
>
> (Resending after removing llvmdev at cs.uiuc.edu and using
>
2016 May 11
4
Filter optimization remarks by the hotness of the code region
> On May 11, 2016, at 3:37 AM, Hal Finkel <hfinkel at anl.gov> wrote:
>
> ----- Original Message -----
>> From: "Adam Nemet" <anemet at apple.com>
>> To: "Hal Finkel" <hfinkel at anl.gov>
>> Cc: "llvm-dev (llvm-dev at lists.llvm.org)" <llvm-dev at lists.llvm.org>
>> Sent: Wednesday, May 11, 2016 1:15:42 AM
2016 Sep 02
4
[ThinLTO] Importing based on PGO data
2016-09-02 15:04 GMT-07:00 Xinliang David Li <davidxl at google.com>:
> On Fri, Sep 2, 2016 at 2:58 PM, Piotr Padlewski
> <piotr.padlewski at gmail.com> wrote:
> > Hi,
> > I am working right now on importing based on PGO/FDO data. There is one
> > issue that I found - when we calculate the list of imports, we can't get
> the
> > ProfileSummaryInfo,
2016 Apr 18
2
Move InlineCost.cpp out of Analysis?
On 04/18/2016 04:05 PM, Easwaran Raman via llvm-dev wrote:
>
>
> On Mon, Apr 18, 2016 at 3:25 PM, Chandler Carruth <chandlerc at gmail.com
> <mailto:chandlerc at gmail.com>> wrote:
>
> On Mon, Apr 18, 2016 at 3:20 PM Easwaran Raman <eraman at google.com
> <mailto:eraman at google.com>> wrote:
>
> On Mon, Apr 18, 2016 at 3:00 PM,