similar to: [LLVMdev] Issues with DependenceAnalysis

I am trying to generate PTX code for 'nbody' sample program's kernel (nbody_kernel.cu) using clang/LLVM version 3.2. The nbody CUDA program is available in Nvidia's SDK. I am referring to https://github.com/jholewinski/llvm-ptx-samples project. Following are my commands, clang++ -O4 -S -I/usr/local/cuda/include -emit-llvm -target nvptx64 nbody_kernel.cu -o nbody_kernel.ll

I noticed you're using cuda_runtime.h in the source file. Where are you getting this file? From the CUDA toolkit? Since the error is in the back-end, can you just post the .ll or .bc file you are trying to compile? On Mon, Mar 18, 2013 at 12:42 AM, upit <uday_pitambare at yahoo.com> wrote: > I am trying to generate PTX code for 'nbody' sample program's kernel >

Hi Chandler, Thanks for writing. Could you give me some C (or C++) for an illustrative example. I think I understand your concern, but I'd like to be sure. Thanks, Preston -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20121102/88c02212/attachment.html>

On 02.11.2012, at 15:53, Preston Briggs <preston.briggs at gmail.com> wrote: > Hi Chandler, > > Thanks for writing. > Could you give me some C (or C++) for an illustrative example. > I think I understand your concern, but I'd like to be sure. Hi Preston, The bug report at http://llvm.org/bugs/show_bug.cgi?id=14241 has more details, including a C++ test case. - Ben

I see, thanks Ben. So yes, I certainly misunderstood (more likely "misunderstand") how things work. My initial guess is that a conservative fix is quick and small (make sure the underlying pointers are loop invariant, otherwise give up). A better approach would be to somehow turn code like the example into array references that can be analyzed. I'll need to think about this and do

----- Original Message ----- > From: "Tobias Grosser" <tobias at grosser.es> > To: "preston briggs" <preston.briggs at gmail.com> > Cc: "Benjamin Kramer" <benny.kra at gmail.com>, "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Friday, November 2, 2012 12:56:53 PM > Subject: Re: [LLVMdev]

On 11/02/2012 10:21 AM, Preston Briggs wrote: > > My initial guess is that a conservative fix is quick and small (make > sure the underlying pointers are loop invariant, otherwise give up). A > better approach would be to somehow turn code like the example into > array references that can be analyzed. I'll need to think about this and > do some reading. Hi Preston, I looked

Hello llvm-dev, I'm running a pass that uses the result of llvm::DependenceAnalysisWrapperPass to compute the dependencies between all instructions of a loop. I have the following two examples of code I wish to analyse: example A: ``` void move_one(int *A, unsigned n) { for (unsigned i = 0; i < n-1; ++i) { A[i] = A[i + 1]; } } ``` and example B: ``` void move_one_alt(int *A,

Here's the current code (abstracted a bit) const Instruction *Src, const Instruction *Dst, // make sure they are loads and stores, then const Value *SrcPtr = getPointerOperand(Src); // hides a little casting, then Src->getPointerOperand const Value *DstPtr = getPointerOperand(Dst); // ditto // see how underlying objects alias, then const GEPOperator *SrcGEP =

On 11/02/2012 11:02 AM, Hal Finkel wrote: > ----- Original Message ----- >> From: "Tobias Grosser" <tobias at grosser.es> >> To: "preston briggs" <preston.briggs at gmail.com> >> Cc: "Benjamin Kramer" <benny.kra at gmail.com>, "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> >> Sent: Friday, November

On Thu, May 23, 2013 at 03:40:00PM +0200, Duncan Sands wrote: > Hi Jack, > > On 23/05/13 15:37, Jack Howarth wrote: >> Below are the results for the Polyhedron 2005 benchmarks compiled with llvm/compiler-rt/dragonegg 3.3svn at r182439 against current >> FSF gcc 4.7.3svn and 4.8.1svn. The only major bug remaining in the dragonegg 3.3svn support for gcc 4.8.x is

Hi, I want to create a copy of DependenceAnalysis downstream. At first I tried the HelloWorld tutorial. But then I figured, maybe I should move on to create my pass by mimicking some other pass in LLVM. So, I tried copying DependenceAnalysis itself [1] Although after a lot of time of trying it compiled, I'm pretty sure I have done it completely in the wrong way. What is more, I can't

Hi Philip, Thanks for checking! I'm running my own Foo pass that registers DependenceAnalysisWrapperPass as a prerequisite and then I run it like so: opt -load libfoo.so -foo example.bc This is LLVM 3.9. Cheers, - Stan On Wed, Jun 21, 2017 at 5:40 PM, Philip Pfaffe <philip.pfaffe at gmail.com> wrote: > Hi Stan, > > in both cases I get a consistent anti result. Can you

[CC bollu, mferguson, shil] Am Do., 23. Mai 2019 um 17:13 Uhr schrieb Bardia Mahjour < bmahjour at ca.ibm.com>: > Thanks David and Michael for the clarification. > > I think I understand the rational behind those checks in delinearization > now. > > > Some other languages have stronger guarantees about their array > dimensions accesses being in range. But this being

Hi I want to analyse the memory dependencies which exist in a loop at an intra iteration as well as inter iteration (loop carried dependencies). I looked at the DependenceAnalysis implementation which returns a lot of the information I require (based on a prior AliasAnalysis pass), however I need to pass the Src and Dst instructions in program order. I was wondering how I can collect all the

Hey Preston, I wanted to let you know that we found a really serious problem with DependenceAnalysis in PR14241. In summary, DA seems to have a baked-in assumption that the base pointer of the GEPs it inspects are loop invariant. It appears to only do analysis on the subscripts. This is especially important for LLVM because C++ code (compiled through Clang) very frequently expresses loops as

Hello there, I'm doing some modifications on an ll file generated by llvm just to learn some more about the llvm text intermediate language. However, I'm having some issues while using lli to execute the modified ll, and, although sometimes the program just freezes, the following message is being printed most of the times: 0 libLLVM-3.3svn.dylib 0x000000010fdd813e

Hi Philip, I forgot to mention that I was ignoring loop-independent dependences. If I don't I get an inconsistent, ordered, anti, loop-independent dependence and an inconsistent, ordered, flow, loop-carried dependence for example A. At the same time I get just a consistent, ordered, anti, loop-independent dependence for example B. Here's the .ll code for example A: *; Function Attrs:

Hi Preston, Thank you for the prompt response. You can use DependenceAnalysis to get the info you want by expensively > testing all pairs of memory references. Isn't all pairs testing incorrect in the sense that a pair may only exist for a certain path? Consider the following example. A[i] = 42; // S1 if( condition ) // C1 { A[i] = 20; // S2 } B[i] = A[i];

Hi, Following is a proposal to improve location coverage for Function parameters in LLVM. The patches for review will be posted soon. RFC: [DebugInfo] Improving Debug Information in LLVM to Recover Optimized-out Function Parameters Ananthakrishna Sowda(Cisco), asowda at cisco.com Nikola Prica (RT-RK/Cisco), nprica at rtrk.com Djordje Todorovic(RT-RK/Cisco), djtodorovic at rtrk.com Ivan Baev