similar to: PartialAlias: different start addresses

On 07/14/2017 03:00 PM, Davide Italiano via llvm-dev wrote: > On Fri, Jul 14, 2017 at 12:50 PM, Nuno Lopes via llvm-dev > <llvm-dev at lists.llvm.org> wrote: >> Hi, >> >> I going through the alias analysis documentation >> (http://llvm.org/docs/AliasAnalysis.html) and noticed the following in the >> definition of PartialAlias: >> " >> The

Thank you all for your replies. So here seems to be an agreement that the documentation for PartialAlias is incorrect. Daniel: now you got me wondering about MustAlias. This is what the docs say: "The MustAlias response may only be returned if the two memory objects are *guaranteed to always start at exactly the same location*" This statement is regardless of the access sizes. For

On Sat, Jul 15, 2017 at 5:35 AM, Hal Finkel <hfinkel at anl.gov> wrote: > > On 07/15/2017 04:51 AM, Nuno Lopes wrote: > >> On 07/14/2017 04:37 PM, Nuno Lopes wrote: >>> >>>> Thank you all for your replies. >>>> So here seems to be an agreement that the documentation for >>>> PartialAlias is incorrect. >>>>

> On 07/14/2017 04:37 PM, Nuno Lopes wrote: >> Thank you all for your replies. >> So here seems to be an agreement that the documentation for PartialAlias >> is incorrect. >> >> Daniel: now you got me wondering about MustAlias. This is what the docs >> say: >> "The MustAlias response may only be returned if the two memory objects >> are

On Sun, Jul 16, 2017, 12:45 PM Nuno Lopes <nunoplopes at sapo.pt> wrote: > >On 07/15/2017 04:51 AM, Nuno Lopes wrote: > >>> On 07/14/2017 04:37 PM, Nuno Lopes wrote: > >>>> Thank you all for your replies. > >>>> So here seems to be an agreement that the documentation for > >>>> PartialAlias is incorrect. > >>>>

On Sun, Jul 16, 2017 at 2:34 PM, Nuno Lopes <nunoplopes at sapo.pt> wrote: > On Sun, Jul 16, 2017, 12:45 PM Nuno Lopes wrote: >>> >>>> On 07/15/2017 04:51 AM, Nuno Lopes wrote: >>>> >>>>> On 07/14/2017 04:37 PM, Nuno Lopes wrote: >>>>>> >>>>>>> Thank you all for your replies.

On Thu, Jan 15, 2015 at 1:26 PM, Nick Lewycky <nlewycky at google.com> wrote: > On 15 January 2015 at 13:10, Daniel Berlin <dberlin at dberlin.org> wrote: > >> Yes. >> I've attached an updated patch that does the following: >> >> 1. Fixes the partialalias of globals/arguments >> 2. Enables partialalias for cases where nothing has been unified to

Hello all, I've read the documentation on alias analysis, and I think I understand it literally, but I just want to be sure, because it seems a bit strange. As it says on this web page <http://llvm.org/docs/AliasAnalysis.html>, The MayAlias response is used whenever the two pointers might refer to the > same object. > > The PartialAlias response is used when the two memory

Oh, sorry, i didn't rebase it when i changed the fix, you would have had to apply the first on top of the second. Here is one against HEAD On Wed, Jan 14, 2015 at 12:32 PM, Ana Pazos <apazos at codeaurora.org> wrote: > Daniel, your patch does not apply cleanly. Are you on the tip? > > The code I see there is no line if (QueryResult == MayAlias|| QueryResult == PartialAlias)

Hi, I'm attempting to do some alias analysis & other memory inspection. I've written a pointless AliasAnalysis pass (that says everything must alias) to attempt to verify that my pass is getting picked up & run by opt. I run opt with: opt -load ~/Applications/llvm/lib/MustAA.so -must-aa -aa-eval -debug < trace0.ll I see my pass being initialized, but never being called (I see

Hey Daniel, Thanks again for the help. I'm still a bit confused about the interface to the alias analysis. It seems like we are talking about different interfaces. Has it changed from what the documentation says? As far as I can tell, the documentation takes a specific Value*, and no information about which dynamic execution it is talking about. When you say "Right. It's a

Hello everyone, I am trying to find the alias between a store instruction's pointer operand and function arguments. This is the code, virtual void getAnalysisUsage(AnalysisUsage &AU) const { AU.addRequiredTransitive<AliasAnalysis>(); AU.addPreserved<AliasAnalysis>(); } virtual bool runOnFunction(Function &F) { AliasAnalysis &AA =

Thanks Daniel! I think you've cleared up some of my misconceptions, but I still am a bit confused about some of the corner cases. Suppose we had something like this std::vector<int> A(100); > int* x,y; > x=&A[0]; > for(int i=0; i<100; i++) { > y=&A[i]; > *y=*x; > x=&A[i+1]; > } > Would the load and store instructions be MustAlias? I

On 13 January 2015 at 22:11, Daniel Berlin <dberlin at dberlin.org> wrote: > This is caused by CFLAA returning PartialAlias for a query that BasicAA > can prove is NoAlias. > One of them is wrong. Which one? I'm not sure from your description that this is a chaining issue. PartialAlias doesn't chain and isn't supposed to, it's a final answer just like NoAlias and

Inline - George > On Jan 14, 2015, at 10:49 AM, Daniel Berlin <dberlin at dberlin.org> wrote: > > > >> On Tue, Jan 13, 2015 at 11:26 PM, Nick Lewycky <nlewycky at google.com> wrote: >>> On 13 January 2015 at 22:11, Daniel Berlin <dberlin at dberlin.org> wrote: >>> This is caused by CFLAA returning PartialAlias for a query that BasicAA can

Hello all, I observed that BasicAA alias query returns PartialAlias between different fields of a structure. Following is the test program and -print–all-alias-modref-info output: --- ; test.ll target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" %"type" = type { [10 x i32], i64 } define void

Hello, I am building the SPEC 2006 Benchmark with Clang as the compiler. I have written a function pass in LLVM and I am trying to run that for SPEC by invoking the pass in the build options of SPEC. The build options of SPEC are in a *.cfg config file, which allows us to specify the choice of compiler while building SPEC. (https://www.spec.org/cpu2006/Docs/install-guide-unix.html) The pass

On Thu, Aug 14, 2014 at 6:37 AM, Daniel Berlin <dberlin at dberlin.org> wrote: > On Wed, Aug 13, 2014 at 8:35 PM, Jeremy Salwen <jeremysalwen at gmail.com> wrote: >> Hey Daniel, >> >> Thanks again for the help. I'm still a bit confused about the interface to >> the alias analysis. It seems like we are talking about different >> interfaces. >

Hi, We've seen a similar case recently, where BasicAA returns PartialAlias for the access of two different fields of a structure. We noticed this since Lint complained about it when checking for aliasing beteen "noalias" attributed parameters: opt -S -lint ./alias.ll gave Unusual: noalias argument aliases another argument on the (silly) function: %rec7 = type { i16, i16, i16

Can you send me actual LLVM IR or a preprocessed source from using -E? I don't have a machine handy that has headers that target that arch. On Tue Jan 13 2015 at 4:33:29 PM Daniel Berlin <dberlin at dberlin.org> wrote: > Anything other than noalias or mustalias should be getting passed down the > stack, so either that is not happening or CFL aa is giving better answers > and