similar to: RFC: Reducing Instr PGO size overhead

On Fri, Sep 4, 2015 at 9:11 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > On Fri, Sep 4, 2015 at 5:42 PM, Xinliang David Li <davidxl at google.com> > wrote: >> >> On Fri, Sep 4, 2015 at 5:21 PM, Sean Silva <chisophugis at gmail.com> wrote: >> > >> > >> > On Fri, Sep 4, 2015 at 3:57 PM, Xinliang David Li <davidxl at

>> >> >> >> yes -- it is fixed length (8byte) blob which may include null byte in >> >> the middle. >> > >> > >> > For reference, MD5 sum is 16 bytes (128-bit): >> > https://en.wikipedia.org/wiki/MD5 >> >> yes, LLVM's MD5 hash only takes the lower 64bit. >> >> >> > >> >>

> > I think it is reasonable to simply replace the key we currently use with > MD5(key) for getting a size reduction. In practice for my use cases, I have > not observed any of the issues you mentioned under "Large size of overhead > can limit the usability of PGO greatly", but I can understand that some of > these issues could become problems in Google's use case.

On Fri, Oct 9, 2015 at 3:58 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > On Wed, Oct 7, 2015 at 11:12 PM, Xinliang David Li <davidxl at google.com> > wrote: >> >> There is no further response to this, so I will assume general >> direction of solution-3 is acceptable ;) > No response does not mean "LGTM". > What I meant is that

We are now very close to push the final stage of the PGO size reduction task. Here is the updated plan going forward: 1) In this round, the format of the indexed profile data won't be unchanged. 2) there will be *no* changes in user interfaces to all profiling related tools including llvm-profdata, llvm-cov -- the change will be transparent in terms of PGO usability. 3) The implementation

There is no further response to this, so I will assume general direction of solution-3 is acceptable ;) Solution-3 can be further improved. Instead of using static symbol table (with zero size __llvm_prf_nm symbols) to store function names for profile display and coverage mapping, the function names can be stored compressed in a non-allocatable section. The compression ratio for function name

On Fri, Sep 4, 2015 at 5:21 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > On Fri, Sep 4, 2015 at 3:57 PM, Xinliang David Li <davidxl at google.com> > wrote: >> >> > >> > I think it is reasonable to simply replace the key we currently use with >> > MD5(key) for getting a size reduction. In practice for my use cases, I >> >

On Fri, Sep 4, 2015 at 11:03 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > On Fri, Sep 4, 2015 at 10:11 PM, Xinliang David Li <davidxl at google.com> > wrote: >> >> On Fri, Sep 4, 2015 at 9:11 PM, Sean Silva <chisophugis at gmail.com> wrote: >> > >> > >> > On Fri, Sep 4, 2015 at 5:42 PM, Xinliang David Li <davidxl at

On Tue, May 24, 2016 at 3:41 PM, Vedant Kumar <vsk at apple.com> wrote: > > > On May 23, 2016, at 8:56 PM, Xinliang David Li <davidxl at google.com> > wrote: > > > > On Mon, May 23, 2016 at 8:23 PM, Sean Silva <chisophugis at gmail.com> > wrote: > > Jake and I have been integrating IRPGO on PS4, and we've identified 3 > remaining work

On Thu, Jun 2, 2016 at 5:30 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > On Thu, Jun 2, 2016 at 2:51 PM, Frédéric Riss <friss at apple.com> wrote: > >> >> On Jun 2, 2016, at 12:10 AM, Sean Silva <chisophugis at gmail.com> wrote: >> >> >> >> On Wed, Jun 1, 2016 at 5:46 PM, Frédéric Riss <friss at apple.com> wrote:

> On Jun 1, 2016, at 1:46 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > > On Tue, May 31, 2016 at 6:02 PM, Frédéric Riss <friss at apple.com <mailto:friss at apple.com>> wrote: > >> On May 24, 2016, at 5:21 PM, Sean Silva <chisophugis at gmail.com <mailto:chisophugis at gmail.com>> wrote: >> >> >> >> On

It sounds to me we are likely to converge on the following: 1) Making IR/llvm based PGO the default; 2) Enhance -fcoverage-mapping such that it automatically turns on FE based instrumentation 3) if -fcoverage-mapping is used together with -fprofile-instr-generate, -fcoverage-mapping serves as a switch to turn on FE based instrumetnation All the above are transparent to users. The following are

> On May 24, 2016, at 5:21 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > > On Tue, May 24, 2016 at 3:41 PM, Vedant Kumar <vsk at apple.com <mailto:vsk at apple.com>> wrote: > > > On May 23, 2016, at 8:56 PM, Xinliang David Li <davidxl at google.com <mailto:davidxl at google.com>> wrote: > > > > On Mon, May 23, 2016 at

> On Jun 2, 2016, at 12:10 AM, Sean Silva <chisophugis at gmail.com> wrote: > > > > On Wed, Jun 1, 2016 at 5:46 PM, Frédéric Riss <friss at apple.com <mailto:friss at apple.com>> wrote: > >> On Jun 1, 2016, at 1:46 PM, Sean Silva <chisophugis at gmail.com <mailto:chisophugis at gmail.com>> wrote: >> >> >> >> On

Hi, all Recently I'm trying to use LLVM PGO and autoFDO. However I have some problems in the process. LLVM source code is updated on April 9th. Operating system is SUSE x86_64 1. Problems in instrumentation based PGO: clang -O2 -fprofile-instr-generate test.c -o a.out ./a.out (then default.profraw is generated) clang -O2 -fprofile-instr-use=default.profraw test.c -o a.out

Quick update. I've gotten derailed from posting a patch for this due to focusing on higher priority PGO inlining work. No ETA. -- Sean Silva On Fri, Jun 3, 2016 at 6:06 PM, Sean Silva <chisophugis at gmail.com> wrote: > > > On Thu, Jun 2, 2016 at 6:41 PM, Xinliang David Li <davidxl at google.com> > wrote: > >> >> >> On Thu, Jun 2, 2016 at 5:30

Hi Diego, thanks for clarifying the difference between the two formats. I have noticed the new note in the "Sample Profile Format" section of the Clang guide clarifying that it is different from the coverage format. So, my further question is... Am I right in understanding that both formats can be used for PGO purposes then? I have tried the following, as in the Clang user guide: $

> On May 23, 2016, at 8:56 PM, Xinliang David Li <davidxl at google.com> wrote: > > On Mon, May 23, 2016 at 8:23 PM, Sean Silva <chisophugis at gmail.com> wrote: > Jake and I have been integrating IRPGO on PS4, and we've identified 3 remaining work items. > > Sean, thanks for the write up. It matches very well with what we think as well. + 1 > - Driver

Hi, I have a question regarding PGO. I collected profile data with the instrumentation build (-fprofile-instr-generate) and provided for PGO optimization in the second build (with -fprofile-instr-use=xxx.profdata). This works fine. Then I tried to provide the profile data to opt using the option -pgo-instr-use, but this causes an error with the message: "Not an IR level instrumentation

On Fri, May 22, 2015 at 11:16 AM, Dario Domizioli <dario.domizioli at gmail.com> wrote: > Hi all, > > I am a bit confused about the documentation of the format of the profile > data file. > > The Clang user guide here describes it as an ASCII text file: > http://clang.llvm.org/docs/UsersManual.html#sample-profile-format > > Whereas the posts above and the