search for: aliasanalysis

...PA. Now I am implementing a Program Dependence Graph(PDG) on LLVM. I have 4 passes here: 1. ProgramDependenceGraph (a *ModulePass *on the highest level) 2. DataDependenceGraph (a Intermediate *FunctionPass*). 3. FlowDependenceAnalysis Pass (a intermediate *FunctionPass*) which uses llvm built-in AliasAnalysis (-basicaa) 4. AliasAnalysis Pass (LLVM built-in Pass) When my call chain is DatadependenceGraph <-- FlowDependenceAnalysis <-- AliasAnalysis everything is fine and basicaa is executed successfully. My problem is, *when I use a Module Pass to call a Function Pass, the low level AliasAnaly...

I want to check if the values a and b in the program alias. int main() { int *a,*b; a=(int *)malloc(sizeof(int)); b=(int *)malloc(sizeof(int)); *a=10; *b=8; return 0; } I use the below code for this (getAnalysisUsage method has been defined) AliasAnalysis::Location loc1=AliasAnalysis::Location(k1); //a AliasAnalysis::Location loc2=AliasAnalysis::Location(k2); //b AliasAnalysis::AliasResult ar=AA.alias(loc1,loc2); But I get ar=1 i.e May Alias result. Where am I going wrong? I have included -basicaa option in the opt command for running this. -------...

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 only may alias results...

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 = getAnalysis<AliasAnalysis>(); for(Function::iterator i=F.begin();i!=F.end();++i){ for(BasicBlock::iterator j=i->begin();j!=i-&gt...

...to check if the values a and b in the program alias. > > int main() { > int *a,*b; > a=(int *)malloc(sizeof(int)); > b=(int *)malloc(sizeof(int)); > *a=10; > *b=8; > return 0; > } > > I use the below code for this (getAnalysisUsage method has been defined) > > AliasAnalysis::Location loc1=AliasAnalysis::Location(k1); //a > AliasAnalysis::Location loc2=AliasAnalysis::Location(k2); //b > AliasAnalysis::AliasResult ar=AA.alias(loc1,loc2); > > But I get ar=1 i.e May Alias result. Where am I going wrong? did you run a basic set of optimizers first? Alias anal...

...ith existing AA (andersen for example) : when calling with opt, this works well, but when adding in local PassManager ( with add() ), it is not working (I test this with the DeadStoreEliminationPass which performs an AA). In particular, the pass is run (runOnFunction) but the derived method from AliasAnalysis (like 'alias' or 'getModRefInfo') are not chained with those from basicAA when needed. Now, i'm trying to understand how opt, RegisterPass, RegisterAnalysisGroup etc, are working, but it is quite difficult (very high level C++!) Thank you. Julien John Criswell a écrit : &...

...(int *)malloc(sizeof(int)); *a=15; map(a); return 0; } I want to check if the pointer operand of each store instruction aliases with the function's arguments. I have used below code for this, virtual void getAnalysisUsage(AnalysisUsage &AU) const { AU.addRequiredTransitive<AliasAnalysis>(); AU.addPreserved<AliasAnalysis>(); } virtual bool runOnFunction(Function &F) { AliasAnalysis &AA = getAnalysis<AliasAnalysis>(); for(Function::iterator i=F.begin();i!=F.end();++i){ for(BasicBlock::iterator j=i->begin();j!=i->end();++j) {...

Just want to test out the LLVM's AliasAnalysis::getModRefInfo API. The input C code is very simple: void foo(int *a, int *b) { for(int i=0; i<10; i++) b[i] = a[i]*a[i]; } int main() { int a[10]; int b[10]; for(int i=0; i<10; i++) a[i] = i; foo(a,b); return 0; } Obviously, for "foo", it only reads from a...

...r example) : when calling with opt, this works > well, but > when adding in local PassManager ( with add() ), it is not working (I > test this with > the DeadStoreEliminationPass which performs an AA). > In particular, the pass is run (runOnFunction) but the derived method from > AliasAnalysis (like 'alias' or 'getModRefInfo') are not chained with > those from > basicAA when needed. > > Now, i'm trying to understand how opt, RegisterPass, RegisterAnalysisGroup > etc, are working, but it is quite difficult (very high level C++!) > > Thank you. >...

...Manager.cpp:616: void llvm::PMTopLevelManager::schedulePass(llvm::Pass*): Assertion `PI && "Expected required passes to be initialized"' failed. The strangest thing is the opt doesn't suffer from this issue. please note that directly use -functionattrs, it can run without AliasAnalysis. Could you explain why? liuxin at rd58:~/testbed$ opt -functionattrs -debug-pass=Structure < pf.bc > /dev/null Pass Arguments: -targetlibinfo -no-aa -basiccg -functionattrs -preverify -domtree -verify Target Library Information No Alias Analysis (always returns 'may' alias) Modu...

...ur own C++ tool that creates a PassManager object and then explicitly adds passes using the add() method of PassManager. Is this correct? In that case, I think all you need to do is to explicitly specify your alias analysis as one of the passes to run: PassManager Passes; Passes.add (new YourAliasAnalysisPass()); Passes.add (new WhateverPassUsesTheAliasAnalysisInterface()); Creating a pass in the AliasAnalysis group doesn't mean that it will automatically be run when an alias analysis is needed. Rather, what it means is that *if* a pass requests an AliasAnalysis group pass *and* your pass h...

Hi ! I'm writting an AliasAnalysis using the online tutorial (http://www.llvm.org/docs/AliasAnalysis.html). My problem is to chain this pass (function Pass in my case) with the basicAA ... I know that my pass is running (runOnFunction) but the virtual methods derived from AliasAnalysis (alias, getModRefInfo, etc ... ) are never...

Hi ! In my quest of implementing my own AA, i understood that it doesn't work because i don't use the 'opt' tool but i create my own PassManager (this for other reasons). The problem is the same with other existing AA (AndersensPass or globalModRefPass) : these AApasses are not chained with the basicAA when they are created in PassManager ... So my question is now : how to

...3 PM, Jingyue Wu <jingyue at google.com> wrote: > > > > On Thu, Apr 24, 2014 at 4:38 PM, Matthew O'Connor <thegreendragon at gmail.com> wrote: > 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 on...

...efactoring the alias analysis layers to remove the usage of analysis groups and make the logic sharable between old and new pass managers, and I have a couple of questions below. As background, the overall plan that I've discussed with Hal and a few others previously is as follows: - Create an AliasAnalysisManager which is provided by a normal analysis pass. - Use type erasure to register classes which conform to the core AliasAnalysis concept with the AliasAnalysisManager. - The concept will consist solely of the virtual methods currently on AliasAnalysis -- all the helpers and such will just be dire...

...>> >> int main() { >> int *a,*b; >> a=(int *)malloc(sizeof(int)); >> b=(int *)malloc(sizeof(int)); >> *a=10; >> *b=8; >> return 0; >> } >> >> I use the below code for this (getAnalysisUsage method has been defined) >> >> AliasAnalysis::Location loc1=AliasAnalysis::Location(k1); //a >> AliasAnalysis::Location loc2=AliasAnalysis::Location(k2); //b >> AliasAnalysis::AliasResult ar=AA.alias(loc1,loc2); >> >> But I get ar=1 i.e May Alias result. Where am I going wrong? > > did you run a basic set of opt...

Hi all, First time posting to llvmdev, be gentle :). I'm working on an AliasAnalysis implementation and running into an issue on 2.7, that doesn't exist in 2.6 as far as I can tell. Short version: has anyone been able to load an AliasAnalysis module into 2.7's opt? Longer version: Even with a dummy pass implementation (just returns MayAlias for everything), I'm getti...

Something must be wrong, more probable on my side. So the C source code is unchanged, I just did another experiment to first extract all the GEPs in the code, and call AliasAnalysis::alias on each pair of GEPs. Here is the code: AliasAnalysis &AA = getAnalysis<AliasAnalysis>(); TargetData &TD = getAnalysis<TargetData>(); for (Module::iterator it = M.begin(); it != M.end(); it++){ Function &F = *it; errs().write_escape...

Hi all, I want to find memory dependency between CallInst instruction and other. So i used the following code: * AliasAnalysis &AA=getAnalysis<AliasAnalysis>();* * if(isa<StoreInst>(inst1)){* * ** **if(isa<CallInst>(inst2))**{* * CallInst *call_inst2= dyn_cast<CallInst>(inst2); * * if(AA.getModRefInfo(inst1,call_inst2)==mod)**{* * //* * } * *...

Hi Hal, Thanks. How about a symbol with two different immediate offsets - the Value* would be the same, right? I don't see how AliasAnalysis::Location would handle this... And BasicAliasAnalysis does if (V1 == V2) return MustAlias; , so I'm not sure how this would be done .. ? /Jonas > -----Original Message----- > From: Hal Finkel [mailto:hfinkel at anl.gov] > Sent: Tuesday, April 16, 2013 7:35 PM > To: Jonas Pauls...