similar to: [LLVMdev] RFC: A plan for stateful alias analysis in LLVM

----- Original Message ----- > From: "Chris Lattner" <clattner at apple.com> > To: "Chandler Carruth" <chandlerc at gmail.com> > Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu>, "Hal Finkel" <hfinkel at anl.gov>, "Justin Bogner" > <mail at justinbogner.com>, "Duncan Exon Smith"

Ok folks, I wrote up the general high-level thoughts I have about stateful AA in a separate thread. But we need to sort out the completely and horribly broken aspects of GlobalsModRef today, and the practical steps forward. This email is totally about the practical stuff. Now, as to why I emailed this group of people and with this subject, the only pass pipeline that includes GlobalsModRef, is

Greetings folks, As I'm working on refactoring the AA interfaces in LLVM to prepare for the new pass manager, I keep hitting issues. Some of the complexity that is hitting this stems from the update API, which consists of three virtual functions: deleteValue(Value *V) copyValue(Value *From, Value *To) addEscapingUse(Use &U) These interfaces are *very* rarely called. Here are the only

On Mon, Jul 13, 2015 at 10:21 PM Chris Lattner <clattner at apple.com> wrote: > > > On Jul 13, 2015, at 8:19 PM, Chandler Carruth <chandlerc at gmail.com> > wrote: > > > > Ok folks, > > > > I wrote up the general high-level thoughts I have about stateful AA in a > separate thread. But we need to sort out the completely and horribly broken >

Hi I have this program in which fooBuf can only take on NULL or the address of local_fooBuf, and fooBuf and local_fooBuf have scope of the foo function. Therefore there is no way for the fooPtr argument to alias with fooBuf. However, LLVM basicaa and globalsmodref-aa say the 2 pointers may alias. I am thinking whether i should implement a limited form of point-to alias on the fooBuf pointer in

Hi there, I am doing: opt -print-memdeps ./test.bc -analyze -globalsmodref-aa by adding globalsmodref-aa, I am hoping that globalsmodref alias analysis will be used. However, it does not turn out to be so. I found this out by adding some "errs() << " into the source code for that alias analysis. So my question is what should I do to let memory dependency analysis use

----- Original Message ----- > From: "Hal Finkel" <hfinkel at anl.gov> > To: "Chandler Carruth" <chandlerc at gmail.com> > Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu>, "Daniel Berlin" <dannyb at google.com> > Sent: Thursday, July 2, 2015 3:14:38 PM > Subject: Re: AliasAnalysis update interface - a tale

Hello, I'm playing with alias analysis, using the following program: %i = external global int ; <int*> [#uses=2] implementation ; Functions: int %_Z3bari(int %p) { entry: %tmp.0 = load int* %i ; <int> [#uses=1] %tmp.1 = setgt int %tmp.0, 10 ; <bool> [#uses=1] br bool %tmp.1, label %then, label %UnifiedReturnBlock then:

On Jan 3, 2012, at 1:53 PM, Jianzhou Zhao wrote: > I see. I asked the question because LLVM provides several alias > analysis, and I was wondering how to decide which one should be used > for compiling most programs. > > I think the basicaa is the default one, but by looking into its code, > it is not inter-procedural or context-sensitive (I am not 100% sure), > so does not

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

<div>Need help about Alias Analysis.</div><div>I try to detect use-after-free debug in source code. And my analysis is based on LLVM IR.</div><div>I use the following code as a small example. I want to get the result p&&q are alias.</div><div>//uaf.cpp</div><div><div>#include<iostream></div><div>using namespace

Hi Chris, I took a haste look at the "Points-to Analysis in Almost Linear Time" by Steens , your PHD thesis and SteensGaard.cpp in LLVM this afternoon. So I think: 1. Actually the basic algorithm described originally by SteensGaard does not provide MOD/REF information for functions. 2. The context insensitive part of Data Structure Analysis (LocalAnalysis) can be deemed as an

Hello I am trying to enable globalsmodref-aa by default. globalmodref-aa is a ModulePass and therefore can be invalidated and need to be rerun. I see globalsmodref-aa is enabled in LTO passmanager by adding the analysis pass explicitly. I wonder whether globalsmodref-aa can be enabled/run based on pass dependencies, i.e. those indicated in getAnalysisUsage(). Thanks, Xin -------------- next

On Wed, 2007-03-21 at 13:29 -0700, Wei Jiang wrote: > hi, > The llvm alias analysis doc mentioned that llvm have various alias > analysis passes, e.g. steens-aa; but I can't find it in llvm 2.0. Are > these passes obsoleted? Thanks. I think that Steensgaard was part of the data structure analysis which has been moved out of llvm. We currently have -basicaa, -globalsmodref-aa,

On Tuesday 16 May 2006 03:19, Chris Lattner wrote: > On Mon, 15 May 2006, Nai Xia wrote: > > > In other words, if I only use -steens-aa and the data_XXXs are all > > external global variables( and so inComplete ), > > Sounds right! > > > the call to printf will > > make the same effect, which I have tested it. > > > > Am I right ? :) >

On Tue, Jan 3, 2012 at 3:54 PM, Chris Lattner <clattner at apple.com> wrote: > > On Jan 2, 2012, at 9:42 PM, Jianzhou Zhao wrote: > >> Hi, >> >> Chapter 4 in http://llvm.org/pubs/2005-05-04-LattnerPHDThesis.html >> compares the precision of alias analysis in LLVM at that time. Does >> the latest LLVM still follow the similar results? I was also

On Wed, 17 May 2006, Nai Xia wrote: > Unfortunately, I did not locate the lines in steens-aa for "printf" special case. > In ds-aa, I found the lines below: Right, steens-aa and ds-aa share code for "local analysis", they just stitch it together into an interprocedural analysis in different ways. The code below is used for steens-aa. >

On Monday 25 April 2005 14:43, Vladimir Prus wrote: > The 'i' variable is never modified in the program, however, all analyses > except for -globalsmodref-aa report that the > > %tmp.3 = call int %_Z3bari( int %p ) ; <int> [#uses=1] > > instruction can modify 'i'. I'm somewhat surprised, because it looks like > -globalsmodref-aa is the simplest

On Mon, 15 May 2006, Nai Xia wrote: > In other words, if I only use -steens-aa and the data_XXXs are all > external global variables( and so inComplete ), Sounds right! > the call to printf will > make the same effect, which I have tested it. > > Am I right ? :) If you've tested it then, yes you're right :). I haven't played with this stuff for a long time,

Dear all, I was wondering if there are some reliable alias analyses build on top of LLVM other than basicaa. Thank you! Zhiyuan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150407/db07dba3/attachment.html>