SVF::WPAPass Class Reference

#include <WPAPass.h>

Public Types
enum	AliasCheckRule { Conservative , Veto , Precise }

Public Member Functions
	WPAPass ()
	Constructor needs TargetLibraryInfo to be passed to the AliasAnalysis.
virtual	~WPAPass ()
	Destructor.
virtual AliasResult	alias (const SVFValue *V1, const SVFValue *V2)
	Interface expose to users of our pointer analysis, given Value infos.
virtual const PointsTo &	getPts (const SVFValue *value)
	Retrieve points-to set information.
virtual const PointsTo &	getPts (NodeID var)
virtual void	PrintAliasPairs (PointerAnalysis *pta)
	Print all alias pairs.
virtual ModRefInfo	getModRefInfo (const CallICFGNode *callInst)
	Interface of mod-ref analysis to determine whether a CallSite instruction can mod or ref any memory location.
virtual ModRefInfo	getModRefInfo (const CallICFGNode *callInst, const SVFValue *V)
	Interface of mod-ref analysis to determine whether a CallSite instruction can mod or ref a specific memory location, given Location infos.
virtual ModRefInfo	getModRefInfo (const CallICFGNode *callInst1, const CallICFGNode *callInst2)
	Interface of mod-ref analysis between two CallSite instructions.
virtual void	runOnModule (SVFIR *svfModule)
	Run pointer analysis on SVFModule.
virtual std::string	getPassName () const
	PTA name.

Static Public Attributes
static char	ID = 0
	Pass ID.

Private Types
typedef std::vector< PointerAnalysis * >	PTAVector

Private Member Functions
void	runPointerAnalysis (SVFIR *pag, u32_t kind)
	Create pointer analysis according to specified kind and analyze the module.

Private Attributes
PTAVector	ptaVector
	all pointer analysis to be executed.
PointerAnalysis *	_pta
	pointer analysis to be executed.
SVFG *	_svfg
	svfg generated through -ander pointer analysis

Detailed Description

Whole program pointer analysis. This class performs various pointer analysis on the given module.

Definition at line 54 of file WPAPass.h.

Member Typedef Documentation

PTAVector

typedef std::vector<PointerAnalysis*> SVF::WPAPass::PTAVector

private

Definition at line 56 of file WPAPass.h.

Member Enumeration Documentation

AliasCheckRule

enum SVF::WPAPass::AliasCheckRule

Enumerator
Conservative	return MayAlias if any pta says alias
Veto	return NoAlias if any pta says no alias
Precise	return alias result by the most precise pta

Definition at line 62 of file WPAPass.h.

    {
        Conservative,   
        Veto,           
        Precise         
    };

Constructor & Destructor Documentation

WPAPass()

SVF::WPAPass::WPAPass ( )

inline

Constructor needs TargetLibraryInfo to be passed to the AliasAnalysis.

Definition at line 70 of file WPAPass.h.

    {
 
    }

~WPAPass()

WPAPass::~WPAPass ( )

virtual

Destructor.

Destructor

Definition at line 54 of file WPAPass.cpp.

{
    PTAVector::const_iterator it = ptaVector.begin();
    PTAVector::const_iterator eit = ptaVector.end();
    for (; it != eit; ++it)
    {
        PointerAnalysis* pta = *it;
        delete pta;
    }
    ptaVector.clear();
}

Member Function Documentation

alias()

AliasResult WPAPass::alias ( const SVFValue *  V1, const SVFValue *  V2  )

virtual

Interface expose to users of our pointer analysis, given Value infos.

Return alias results based on our points-to/alias analysis TODO: Need to handle PartialAlias and MustAlias here.

TODO: When this method is invoked during compiler optimizations, the IR used for pointer analysis may been changed, so some Values may not find corresponding SVFIR node. In this case, we only check alias between two Values if they both have SVFIR nodes. Otherwise, MayAlias will be returned.

Veto is used by default

Return NoAlias if any PTA gives NoAlias result

Return MayAlias if any PTA gives MayAlias result

Definition at line 174 of file WPAPass.cpp.

{
 
    AliasResult result = AliasResult::MayAlias;
 
    SVFIR* pag = _pta->getPAG();
 
    if (pag->hasValueNode(V1) && pag->hasValueNode(V2))
    {
        if (Options::AliasRule.nothingSet() || Options::AliasRule(Veto))
        {
            result = AliasResult::MayAlias;
 
            for (PTAVector::const_iterator it = ptaVector.begin(), eit = ptaVector.end();
                    it != eit; ++it)
            {
                if ((*it)->alias(V1, V2) == AliasResult::NoAlias)
                    result = AliasResult::NoAlias;
            }
        }
        else if (Options::AliasRule(Conservative))
        {
            result = AliasResult::NoAlias;
 
            for (PTAVector::const_iterator it = ptaVector.begin(), eit = ptaVector.end();
                    it != eit; ++it)
            {
                if ((*it)->alias(V1, V2) == AliasResult::MayAlias)
                    result = AliasResult::MayAlias;
            }
        }
    }
 
    return result;
}

getModRefInfo() [1/3]

ModRefInfo WPAPass::getModRefInfo ( const CallICFGNode *  callInst )

virtual

Interface of mod-ref analysis to determine whether a CallSite instruction can mod or ref any memory location.

Return mod-ref result of a Callsite

Definition at line 221 of file WPAPass.cpp.

{
    assert(Options::PASelected(PointerAnalysis::AndersenWaveDiff_WPA) && Options::AnderSVFG() && "mod-ref query is only support with -ander and -svfg turned on");
    return _svfg->getMSSA()->getMRGenerator()->getModRefInfo(callInst);
}

getModRefInfo() [2/3]

ModRefInfo WPAPass::getModRefInfo ( const CallICFGNode *  callInst, const SVFValue *  V  )

virtual

Interface of mod-ref analysis to determine whether a CallSite instruction can mod or ref a specific memory location, given Location infos.

Interface of mod-ref analysis to determine whether a CallSite instruction can mod or ref a specific memory location, given Value infos

Return mod-ref results of a Callsite to a specific memory location

Definition at line 230 of file WPAPass.cpp.

{
    assert(Options::PASelected(PointerAnalysis::AndersenWaveDiff_WPA) && Options::AnderSVFG() && "mod-ref query is only support with -ander and -svfg turned on");
    return _svfg->getMSSA()->getMRGenerator()->getModRefInfo(callInst, V);
}

getModRefInfo() [3/3]

ModRefInfo WPAPass::getModRefInfo ( const CallICFGNode *  callInst1, const CallICFGNode *  callInst2  )

virtual

Interface of mod-ref analysis between two CallSite instructions.

Return mod-ref result between two CallInsts

Definition at line 239 of file WPAPass.cpp.

{
    assert(Options::PASelected(PointerAnalysis::AndersenWaveDiff_WPA) && Options::AnderSVFG() && "mod-ref query is only support with -ander and -svfg turned on");
    return _svfg->getMSSA()->getMRGenerator()->getModRefInfo(callInst1, callInst2);
}

getPassName()

virtual std::string SVF::WPAPass::getPassName ( ) const

inlinevirtual

PTA name.

Definition at line 107 of file WPAPass.h.

    {
        return "WPAPass";
    }

getPts() [1/2]

const PointsTo & WPAPass::getPts ( const SVFValue *  value )

virtual

Retrieve points-to set information.

Definition at line 157 of file WPAPass.cpp.

{
    assert(_pta && "initialize a pointer analysis first");
    SVFIR* pag = _pta->getPAG();
    return getPts(pag->getValueNode(value));
}

getPts() [2/2]

const PointsTo & WPAPass::getPts ( NodeID  var )

virtual

Definition at line 164 of file WPAPass.cpp.

{
    assert(_pta && "initialize a pointer analysis first");
    return _pta->getPts(var);
}

PrintAliasPairs()

void WPAPass::PrintAliasPairs ( PointerAnalysis *  pta )

virtual

Print all alias pairs.

Definition at line 133 of file WPAPass.cpp.

{
    SVFIR* pag = pta->getPAG();
    for (SVFIR::iterator lit = pag->begin(), elit = pag->end(); lit != elit; ++lit)
    {
        PAGNode* node1 = lit->second;
        PAGNode* node2 = node1;
        for (SVFIR::iterator rit = lit, erit = pag->end(); rit != erit; ++rit)
        {
            node2 = rit->second;
            if(node1==node2)
                continue;
            const SVFFunction* fun1 = node1->getFunction();
            const SVFFunction* fun2 = node2->getFunction();
            AliasResult result = pta->alias(node1->getId(), node2->getId());
            SVFUtil::outs() << (result == AliasResult::NoAlias ? "NoAlias" : "MayAlias")
                            << " var" << node1->getId() << "[" << node1->getValueName()
                            << "@" << (fun1==nullptr?"":fun1->getName()) << "] --"
                            << " var" << node2->getId() << "[" << node2->getValueName()
                            << "@" << (fun2==nullptr?"":fun2->getName()) << "]\n";
        }
    }
}

runOnModule()

void WPAPass::runOnModule ( SVFIR *  pag )

virtual

Run pointer analysis on SVFModule.

We start from here

Definition at line 69 of file WPAPass.cpp.

{
    for (u32_t i = 0; i<= PointerAnalysis::Default_PTA; i++)
    {
        PointerAnalysis::PTATY iPtaTy = static_cast<PointerAnalysis::PTATY>(i);
        if (Options::PASelected(iPtaTy))
            runPointerAnalysis(pag, i);
    }
    assert(!ptaVector.empty() && "No pointer analysis is specified.\n");
}

runPointerAnalysis()

void WPAPass::runPointerAnalysis ( SVFIR *  pag, u32_t  kind  )

private

Create pointer analysis according to specified kind and analyze the module.

Create pointer analysis according to a specified kind and then analyze the module.

Initialize pointer analysis.

support mod-ref queries only for -ander

Definition at line 83 of file WPAPass.cpp.

{
    switch (kind)
    {
    case PointerAnalysis::Andersen_WPA:
        _pta = new Andersen(pag);
        break;
    case PointerAnalysis::AndersenSCD_WPA:
        _pta = new AndersenSCD(pag);
        break;
    case PointerAnalysis::AndersenSFR_WPA:
        _pta = new AndersenSFR(pag);
        break;
    case PointerAnalysis::AndersenWaveDiff_WPA:
        _pta = new AndersenWaveDiff(pag);
        break;
    case PointerAnalysis::Steensgaard_WPA:
        _pta = new Steensgaard(pag);
        break;
    case PointerAnalysis::FSSPARSE_WPA:
        _pta = new FlowSensitive(pag);
        break;
    case PointerAnalysis::VFS_WPA:
        _pta = new VersionedFlowSensitive(pag);
        break;
    case PointerAnalysis::TypeCPP_WPA:
        _pta = new TypeAnalysis(pag);
        break;
    default:
        assert(false && "This pointer analysis has not been implemented yet.\n");
        return;
    }
 
    ptaVector.push_back(_pta);
    _pta->analyze();
    if (Options::AnderSVFG())
    {
        SVFGBuilder memSSA(true);
        assert(SVFUtil::isa<AndersenBase>(_pta) && "supports only andersen/steensgaard for pre-computed SVFG");
        SVFG *svfg = memSSA.buildFullSVFG((BVDataPTAImpl*)_pta);
        if (Options::PASelected(PointerAnalysis::AndersenWaveDiff_WPA))
            _svfg = svfg;
    }
 
    if (Options::PrintAliases())
        PrintAliasPairs(_pta);
}

Member Data Documentation

_pta

PointerAnalysis* SVF::WPAPass::_pta

private

pointer analysis to be executed.

Definition at line 117 of file WPAPass.h.

_svfg

SVFG* SVF::WPAPass::_svfg

private

svfg generated through -ander pointer analysis

Definition at line 118 of file WPAPass.h.

ID

char WPAPass::ID = 0

static

Pass ID.

Definition at line 60 of file WPAPass.h.

ptaVector

PTAVector SVF::WPAPass::ptaVector

private

all pointer analysis to be executed.

Definition at line 116 of file WPAPass.h.

---

The documentation for this class was generated from the following files:

• /home/runner/work/SVF/SVF/svf/include/WPA/WPAPass.h
• /home/runner/work/SVF/SVF/svf/lib/WPA/WPAPass.cpp