similar to: [LLVMdev] profile guided optimizations

I see that we do not inline a function marked as "always-inline" if it contains indirect branches ? what are the reasons behind this criterion ? Thanks Trent -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150129/92bf577a/attachment.html>

Hi I see when LLVM builds the CallGraph SCCs. a function calling through a function pointer is conservatively assumed to call internal and external functions. Therefore, it has an edges pointing to the externalnode2, ie. the externalnode representing outgoing calls from this module. does LLVM have any function pointer analysis capabilities in the mainline ? Thanks, -Trent

Hi! My name is Gratian and I would like to participate to GSOC 2011. I'm interested in profile-guided optimizations, and I want to implement two optimizations that can bring tangible benefits for most applications: profile-guided function inlining and basic block positioning. Inlining can be greatly improved if we take into consideration how many times the function we want to inline was

Hi Xin, Thank you for your reply! I have tried the 3 alias analyses you have mentioned on LLVM 3.5: 1) $ opt -globalsmodref-aa -aa-eval < xxx.bc > /dev/null (May-alias response 100%) 2) $ opt -tbaa -aa-eval < xxx.bc > /dev/null (May-alias response 100%) 3) $ opt -cfl-aa -aa-eval < xxx.bc> /dev/null (Unknown command line argument '-cfl-aa') It seems that they are not

I was looking over the open projects page and I am curious about the current status of the profile guided optimization support mentioned here. I am curious what developments have taken place in this area since the page was updated and about where would I find the relevant portions of the code in the source. Thanks in advance, Carter.

Does LLVM have loop multiversioning ? it seems it does not with clang++ -O3 -mllvm -debug-pass=Arguments program.c -c bash-4.1$ clang++ -O3 -mllvm -debug-pass=Arguments fast_algorithms.c -c clang-3.6: warning: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated Pass Arguments: -datalayout -notti -basictti -x86tti -targetlibinfo -no-aa -tbaa -scoped-noalias

On Jun 14, 2013, at 10:56 AM, Krzysztof Parzyszek <kparzysz at codeaurora.org> wrote: > > * Function argument value profiling: > - Is the function called with a small set of values for the parameters? > - Is there any value that is particularly frequent for any of the arguments? > - If the function takes pointers, are the pointers usually aligned? > - If the function

On 6/12/2013 4:55 PM, Jakob Stoklund Olesen wrote: > > It seems like we might need a way of representing call graph profiling in addition to the existing branch probabilities? > Metadata on function definitions/declarations perhaps? I agree---the call graph profiling is of critical importance. I guess we should first see what types of data we already know may be useful and see how we

Hi, sorry to be so late with my answer, I was busy finishing my master thesis. On 03/21/2010 11:06 PM, Gener Omer wrote: > > I have finally started my project which is supposed to implement some > algorithms that uses profile information in order to optimize programs. > I have a very basic question for you. I have a very simple source code, > I compiled it with LLVM > >

Hi, I would like to learn the details regarding what exactly PGO does for basic block layout/code placement optimizations in llvm. Could you please point me to some descriptions? Is it close to this paper (Karl Pettis and Robert C. Hansen. 1990. Profile guided code positioning. PLDI'90) http://perso.ensta-paristech.fr/~bmonsuez/Cours/B6-4/Articles/papers15.pdf? Whether it is purely

On Jun 12, 2013, at 2:23 PM, Diego Novillo <dnovillo at google.com> wrote: > In terms of optimizations, our (Google) experience is that > inlining is the key beneficiary of profile information. > Particularly, in big C++ applications. I expect to focus most > of my attention on the inliner. That sounds plausible to me. It seems like we might need a way of representing call

On 07/15/2015 07:05 PM, Hal Finkel wrote: > ----- Original Message ----- >> From: "Xin Tong" <trent.xin.tong at gmail.com> >> To: "Philip Reames" <listmail at philipreames.com> >> Cc: "Hal Finkel" <hfinkel at anl.gov>, llvmdev at cs.uiuc.edu >> Sent: Wednesday, July 15, 2015 6:35:11 PM >> Subject: Re: [LLVMdev] LICM

Hi I do not really understand why frontend generated TBAA metadata is needed for the TBAA pass to work. It seems to me that we can always go up the IR chain and find the base type from which the pointer is derived from. Take the following example. I know %0 = load i32, i32* %a, align 4, !tbaa !1 and store i32 %i.02, i32* %b, align 4, !tbaa !6 do not alias as their metadata !1 = !{!2, !3, i64

On Wed, Jun 12, 2013 at 2:55 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk>wrote: > That sounds plausible to me. It seems like we might need a way of > representing call graph profiling in addition to the existing branch > probabilities? > Agreed. An important consideration here is WPO vs. LTO vs. TU-at-a-time call graphs. > FWIW, the greedy register allocator’s live range

Hi everyone, I would like to share a paper my co-authors and I published at CGO 2013, where we used profiling support in LLVM for efficient code layout randomization: Andrei Homescu, Steven Neisius, Per Larsen, Stefan Brunthaler, Michael Franz. Profile-guided Automated Software Diversity. In Proceedings of the 2013 International Symposium on Code Generation and Optimization, CGO '13,

On Jun 12, 2013, at 3:05 PM, Chandler Carruth <chandlerc at google.com> wrote: > > On Wed, Jun 12, 2013 at 2:55 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote: > That sounds plausible to me. It seems like we might need a way of representing call graph profiling in addition to the existing branch probabilities? > > Agreed. An important consideration here is WPO

Hi all, I would like to know the status of profile-guided optimization. What enhancements could be done to the current implementation? The ideas for profile-guided transformations from [0] are still available? Many thanks. Gener [0] http://llvm.org/OpenProjects.html#profileguided -------------- next part -------------- An HTML attachment was scrubbed... URL:

hello,everyone recently, I analyze the compiler optimization level, so I have searched the usage of profile-guided optimization of LLVM, but little result in google, therefore, could you please list detailed usage of profile-guided optimization? LLVM must be install with flags '--enable-profile'? A example will be pleasure. thanks von -------------- next part -------------- An HTML

sounds like a good idea to me. but one of the current issues of back-patching in the LLVM is that the back-patching is not done atomically on some of the architectures, i.e. Intel x86. and this makes LLVM JIT not thread-safe in lazy compilation mode. what we need to make sure is that the "updating the resolution for a given symbol" you mentioned is done in an atomic fashion. also, how

Dear LLVM community, I am very happy to become a member of this great community. At the German Climate Research Center (DKRZ) I am a PhD student and write my thesis in python. The general topic is Compiler Optimization in High Performance Computing. My use cases are climate models, written in C/C++. In Frankfurt I am working at a HPC Cluster Center and my duties are to monitor and to optimize