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fa41714d8d
RegionStore already lazily abstracted the contents of arrays and structs, when doing an assignment from one array/struct to another we did an explicit element-wise copy, which resulted in a loss of laziness and huge performance problem when analyzing many code bases. Now RegionStoreManager handles such assignments using a new SVal could 'LazyCompoundSVal', which basically means the value of a given struct or array (a MemRegion*) in a specific state (GRState). When we do a load from a field whose encompassing struct binds to a LazyCompoundSVal, we essentially do a field lookup in the original structure. This means we have essentially zero copying of data for structs/arrays and everything stays lazy. llvm-svn: 78268
1822 lines
63 KiB
C++
1822 lines
63 KiB
C++
//== RegionStore.cpp - Field-sensitive store model --------------*- C++ -*--==//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines a basic region store model. In this model, we do have field
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// sensitivity. But we assume nothing about the heap shape. So recursive data
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// structures are largely ignored. Basically we do 1-limiting analysis.
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// Parameter pointers are assumed with no aliasing. Pointee objects of
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// parameters are created lazily.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/Analysis/PathSensitive/MemRegion.h"
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#include "clang/Analysis/PathSensitive/GRState.h"
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#include "clang/Analysis/PathSensitive/GRStateTrait.h"
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#include "clang/Analysis/Analyses/LiveVariables.h"
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#include "clang/Basic/TargetInfo.h"
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#include "llvm/ADT/ImmutableMap.h"
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#include "llvm/ADT/ImmutableList.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/Support/Compiler.h"
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using namespace clang;
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#define HEAP_UNDEFINED 0
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#define USE_EXPLICIT_COMPOUND 0
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// Actual Store type.
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typedef llvm::ImmutableMap<const MemRegion*, SVal> RegionBindingsTy;
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//===----------------------------------------------------------------------===//
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// Fine-grained control of RegionStoreManager.
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//===----------------------------------------------------------------------===//
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namespace {
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struct VISIBILITY_HIDDEN minimal_features_tag {};
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struct VISIBILITY_HIDDEN maximal_features_tag {};
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class VISIBILITY_HIDDEN RegionStoreFeatures {
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bool SupportsFields;
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bool SupportsRemaining;
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public:
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RegionStoreFeatures(minimal_features_tag) :
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SupportsFields(false), SupportsRemaining(false) {}
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RegionStoreFeatures(maximal_features_tag) :
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SupportsFields(true), SupportsRemaining(false) {}
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void enableFields(bool t) { SupportsFields = t; }
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bool supportsFields() const { return SupportsFields; }
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bool supportsRemaining() const { return SupportsRemaining; }
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};
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}
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//===----------------------------------------------------------------------===//
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// Region "Extents"
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//===----------------------------------------------------------------------===//
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//
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// MemRegions represent chunks of memory with a size (their "extent"). This
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// GDM entry tracks the extents for regions. Extents are in bytes.
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//
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namespace { class VISIBILITY_HIDDEN RegionExtents {}; }
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static int RegionExtentsIndex = 0;
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namespace clang {
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template<> struct GRStateTrait<RegionExtents>
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: public GRStatePartialTrait<llvm::ImmutableMap<const MemRegion*, SVal> > {
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static void* GDMIndex() { return &RegionExtentsIndex; }
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};
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}
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//===----------------------------------------------------------------------===//
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// Regions with default values.
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//===----------------------------------------------------------------------===//
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//
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// This GDM entry tracks what regions have a default value if they have no bound
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// value and have not been killed.
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//
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namespace {
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class VISIBILITY_HIDDEN RegionDefaultValue {
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public:
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typedef llvm::ImmutableMap<const MemRegion*, SVal> MapTy;
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};
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}
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static int RegionDefaultValueIndex = 0;
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namespace clang {
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template<> struct GRStateTrait<RegionDefaultValue>
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: public GRStatePartialTrait<RegionDefaultValue::MapTy> {
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static void* GDMIndex() { return &RegionDefaultValueIndex; }
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};
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}
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//===----------------------------------------------------------------------===//
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// Utility functions.
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//===----------------------------------------------------------------------===//
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static bool IsAnyPointerOrIntptr(QualType ty, ASTContext &Ctx) {
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if (ty->isAnyPointerType())
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return true;
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return ty->isIntegerType() && ty->isScalarType() &&
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Ctx.getTypeSize(ty) == Ctx.getTypeSize(Ctx.VoidPtrTy);
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}
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//===----------------------------------------------------------------------===//
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// Main RegionStore logic.
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//===----------------------------------------------------------------------===//
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namespace {
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class VISIBILITY_HIDDEN RegionStoreSubRegionMap : public SubRegionMap {
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typedef llvm::ImmutableSet<const MemRegion*> SetTy;
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typedef llvm::DenseMap<const MemRegion*, SetTy> Map;
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SetTy::Factory F;
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Map M;
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public:
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bool add(const MemRegion* Parent, const MemRegion* SubRegion) {
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Map::iterator I = M.find(Parent);
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if (I == M.end()) {
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M.insert(std::make_pair(Parent, F.Add(F.GetEmptySet(), SubRegion)));
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return true;
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}
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I->second = F.Add(I->second, SubRegion);
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return false;
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}
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void process(llvm::SmallVectorImpl<const SubRegion*> &WL, const SubRegion *R);
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~RegionStoreSubRegionMap() {}
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bool iterSubRegions(const MemRegion* Parent, Visitor& V) const {
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Map::iterator I = M.find(Parent);
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if (I == M.end())
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return true;
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llvm::ImmutableSet<const MemRegion*> S = I->second;
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for (llvm::ImmutableSet<const MemRegion*>::iterator SI=S.begin(),SE=S.end();
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SI != SE; ++SI) {
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if (!V.Visit(Parent, *SI))
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return false;
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}
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return true;
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}
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typedef SetTy::iterator iterator;
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std::pair<iterator, iterator> begin_end(const MemRegion *R) {
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Map::iterator I = M.find(R);
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SetTy S = I == M.end() ? F.GetEmptySet() : I->second;
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return std::make_pair(S.begin(), S.end());
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}
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};
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class VISIBILITY_HIDDEN RegionStoreManager : public StoreManager {
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const RegionStoreFeatures Features;
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RegionBindingsTy::Factory RBFactory;
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const MemRegion* SelfRegion;
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const ImplicitParamDecl *SelfDecl;
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public:
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RegionStoreManager(GRStateManager& mgr, const RegionStoreFeatures &f)
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: StoreManager(mgr),
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Features(f),
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RBFactory(mgr.getAllocator()),
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SelfRegion(0), SelfDecl(0) {
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if (const ObjCMethodDecl* MD =
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dyn_cast<ObjCMethodDecl>(&StateMgr.getCodeDecl()))
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SelfDecl = MD->getSelfDecl();
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}
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virtual ~RegionStoreManager() {}
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SubRegionMap *getSubRegionMap(const GRState *state);
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RegionStoreSubRegionMap *getRegionStoreSubRegionMap(const GRState *state);
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/// getLValueString - Returns an SVal representing the lvalue of a
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/// StringLiteral. Within RegionStore a StringLiteral has an
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/// associated StringRegion, and the lvalue of a StringLiteral is
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/// the lvalue of that region.
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SVal getLValueString(const GRState *state, const StringLiteral* S);
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/// getLValueCompoundLiteral - Returns an SVal representing the
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/// lvalue of a compound literal. Within RegionStore a compound
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/// literal has an associated region, and the lvalue of the
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/// compound literal is the lvalue of that region.
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SVal getLValueCompoundLiteral(const GRState *state, const CompoundLiteralExpr*);
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/// getLValueVar - Returns an SVal that represents the lvalue of a
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/// variable. Within RegionStore a variable has an associated
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/// VarRegion, and the lvalue of the variable is the lvalue of that region.
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SVal getLValueVar(const GRState *state, const VarDecl* VD);
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SVal getLValueIvar(const GRState *state, const ObjCIvarDecl* D, SVal Base);
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SVal getLValueField(const GRState *state, SVal Base, const FieldDecl* D);
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SVal getLValueFieldOrIvar(const GRState *state, SVal Base, const Decl* D);
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SVal getLValueElement(const GRState *state, QualType elementType,
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SVal Base, SVal Offset);
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/// ArrayToPointer - Emulates the "decay" of an array to a pointer
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/// type. 'Array' represents the lvalue of the array being decayed
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/// to a pointer, and the returned SVal represents the decayed
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/// version of that lvalue (i.e., a pointer to the first element of
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/// the array). This is called by GRExprEngine when evaluating
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/// casts from arrays to pointers.
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SVal ArrayToPointer(Loc Array);
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SVal EvalBinOp(const GRState *state, BinaryOperator::Opcode Op,Loc L,
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NonLoc R, QualType resultTy);
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Store getInitialStore() { return RBFactory.GetEmptyMap().getRoot(); }
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/// getSelfRegion - Returns the region for the 'self' (Objective-C) or
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/// 'this' object (C++). When used when analyzing a normal function this
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/// method returns NULL.
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const MemRegion* getSelfRegion(Store) {
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if (!SelfDecl)
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return 0;
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if (!SelfRegion) {
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const ObjCMethodDecl *MD = cast<ObjCMethodDecl>(&StateMgr.getCodeDecl());
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SelfRegion = MRMgr.getObjCObjectRegion(MD->getClassInterface(),
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MRMgr.getHeapRegion());
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}
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return SelfRegion;
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}
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//===-------------------------------------------------------------------===//
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// Binding values to regions.
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//===-------------------------------------------------------------------===//
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const GRState *InvalidateRegion(const GRState *state, const MemRegion *R,
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const Expr *E, unsigned Count);
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private:
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void RemoveSubRegionBindings(RegionBindingsTy &B,
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RegionDefaultValue::MapTy &DVM,
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RegionDefaultValue::MapTy::Factory &DVMFactory,
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const MemRegion *R,
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RegionStoreSubRegionMap &M);
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public:
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const GRState *Bind(const GRState *state, Loc LV, SVal V);
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const GRState *BindCompoundLiteral(const GRState *state,
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const CompoundLiteralExpr* CL, SVal V);
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const GRState *BindDecl(const GRState *state, const VarDecl* VD, SVal InitVal);
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const GRState *BindDeclWithNoInit(const GRState *state, const VarDecl* VD) {
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return state;
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}
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/// BindStruct - Bind a compound value to a structure.
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const GRState *BindStruct(const GRState *, const TypedRegion* R, SVal V);
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const GRState *BindArray(const GRState *state, const TypedRegion* R, SVal V);
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/// KillStruct - Set the entire struct to unknown.
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const GRState *KillStruct(const GRState *state, const TypedRegion* R);
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const GRState *setDefaultValue(const GRState *state, const MemRegion* R, SVal V);
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Store Remove(Store store, Loc LV);
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//===------------------------------------------------------------------===//
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// Loading values from regions.
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//===------------------------------------------------------------------===//
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/// The high level logic for this method is this:
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/// Retrieve (L)
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/// if L has binding
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/// return L's binding
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/// else if L is in killset
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/// return unknown
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/// else
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/// if L is on stack or heap
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/// return undefined
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/// else
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/// return symbolic
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SValuator::CastResult Retrieve(const GRState *state, Loc L,
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QualType T = QualType());
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SVal RetrieveElement(const GRState *state, const ElementRegion *R);
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SVal RetrieveField(const GRState *state, const FieldRegion *R);
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SVal RetrieveObjCIvar(const GRState *state, const ObjCIvarRegion *R);
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SVal RetrieveVar(const GRState *state, const VarRegion *R);
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SVal RetrieveLazySymbol(const GRState *state, const TypedRegion *R);
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SValuator::CastResult CastRetrievedVal(SVal val, const GRState *state,
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const TypedRegion *R, QualType castTy);
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/// Retrieve the values in a struct and return a CompoundVal, used when doing
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/// struct copy:
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/// struct s x, y;
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/// x = y;
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/// y's value is retrieved by this method.
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SVal RetrieveStruct(const GRState *St, const TypedRegion* R);
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SVal RetrieveArray(const GRState *St, const TypedRegion* R);
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std::pair<const GRState*, const MemRegion*>
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GetLazyBinding(RegionBindingsTy B, const MemRegion *R);
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const GRState* CopyLazyBindings(nonloc::LazyCompoundVal V,
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const GRState *state,
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const TypedRegion *R);
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//===------------------------------------------------------------------===//
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// State pruning.
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//===------------------------------------------------------------------===//
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/// RemoveDeadBindings - Scans the RegionStore of 'state' for dead values.
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/// It returns a new Store with these values removed.
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void RemoveDeadBindings(GRState &state, Stmt* Loc, SymbolReaper& SymReaper,
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llvm::SmallVectorImpl<const MemRegion*>& RegionRoots);
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//===------------------------------------------------------------------===//
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// Region "extents".
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//===------------------------------------------------------------------===//
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const GRState *setExtent(const GRState *state, const MemRegion* R, SVal Extent);
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SVal getSizeInElements(const GRState *state, const MemRegion* R);
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//===------------------------------------------------------------------===//
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// Region "views".
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//===------------------------------------------------------------------===//
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const GRState *AddRegionView(const GRState *state, const MemRegion* View,
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const MemRegion* Base);
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const GRState *RemoveRegionView(const GRState *state, const MemRegion* View,
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const MemRegion* Base);
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//===------------------------------------------------------------------===//
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// Utility methods.
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//===------------------------------------------------------------------===//
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static inline RegionBindingsTy GetRegionBindings(Store store) {
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return RegionBindingsTy(static_cast<const RegionBindingsTy::TreeTy*>(store));
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}
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void print(Store store, llvm::raw_ostream& Out, const char* nl,
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const char *sep);
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void iterBindings(Store store, BindingsHandler& f) {
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// FIXME: Implement.
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}
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// FIXME: Remove.
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BasicValueFactory& getBasicVals() {
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return StateMgr.getBasicVals();
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}
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// FIXME: Remove.
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ASTContext& getContext() { return StateMgr.getContext(); }
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};
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} // end anonymous namespace
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//===----------------------------------------------------------------------===//
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// RegionStore creation.
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//===----------------------------------------------------------------------===//
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StoreManager *clang::CreateRegionStoreManager(GRStateManager& StMgr) {
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RegionStoreFeatures F = maximal_features_tag();
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return new RegionStoreManager(StMgr, F);
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}
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StoreManager *clang::CreateFieldsOnlyRegionStoreManager(GRStateManager &StMgr) {
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RegionStoreFeatures F = minimal_features_tag();
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F.enableFields(true);
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return new RegionStoreManager(StMgr, F);
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}
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void
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RegionStoreSubRegionMap::process(llvm::SmallVectorImpl<const SubRegion*> &WL,
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const SubRegion *R) {
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const MemRegion *superR = R->getSuperRegion();
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if (add(superR, R))
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if (const SubRegion *sr = dyn_cast<SubRegion>(superR))
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WL.push_back(sr);
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}
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RegionStoreSubRegionMap*
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RegionStoreManager::getRegionStoreSubRegionMap(const GRState *state) {
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RegionBindingsTy B = GetRegionBindings(state->getStore());
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RegionStoreSubRegionMap *M = new RegionStoreSubRegionMap();
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llvm::SmallVector<const SubRegion*, 10> WL;
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for (RegionBindingsTy::iterator I=B.begin(), E=B.end(); I!=E; ++I)
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if (const SubRegion *R = dyn_cast<SubRegion>(I.getKey()))
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M->process(WL, R);
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RegionDefaultValue::MapTy DVM = state->get<RegionDefaultValue>();
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for (RegionDefaultValue::MapTy::iterator I = DVM.begin(), E = DVM.end();
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I != E; ++I)
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if (const SubRegion *R = dyn_cast<SubRegion>(I.getKey()))
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M->process(WL, R);
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// We also need to record in the subregion map "intermediate" regions that
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// don't have direct bindings but are super regions of those that do.
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while (!WL.empty()) {
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const SubRegion *R = WL.back();
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WL.pop_back();
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M->process(WL, R);
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}
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return M;
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}
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SubRegionMap *RegionStoreManager::getSubRegionMap(const GRState *state) {
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return getRegionStoreSubRegionMap(state);
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}
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//===----------------------------------------------------------------------===//
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// Binding invalidation.
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//===----------------------------------------------------------------------===//
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void
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RegionStoreManager::RemoveSubRegionBindings(RegionBindingsTy &B,
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RegionDefaultValue::MapTy &DVM,
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RegionDefaultValue::MapTy::Factory &DVMFactory,
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const MemRegion *R,
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RegionStoreSubRegionMap &M) {
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RegionStoreSubRegionMap::iterator I, E;
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for (llvm::tie(I, E) = M.begin_end(R); I != E; ++I)
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RemoveSubRegionBindings(B, DVM, DVMFactory, *I, M);
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B = RBFactory.Remove(B, R);
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DVM = DVMFactory.Remove(DVM, R);
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}
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const GRState *RegionStoreManager::InvalidateRegion(const GRState *state,
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const MemRegion *R,
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const Expr *E,
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unsigned Count) {
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ASTContext& Ctx = StateMgr.getContext();
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// Strip away casts.
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R = R->getBaseRegion();
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// Remove the bindings to subregions.
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{
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// Get the mapping of regions -> subregions.
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llvm::OwningPtr<RegionStoreSubRegionMap>
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SubRegions(getRegionStoreSubRegionMap(state));
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RegionBindingsTy B = GetRegionBindings(state->getStore());
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RegionDefaultValue::MapTy DVM = state->get<RegionDefaultValue>();
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RegionDefaultValue::MapTy::Factory &DVMFactory =
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state->get_context<RegionDefaultValue>();
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RemoveSubRegionBindings(B, DVM, DVMFactory, R, *SubRegions.get());
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state = state->makeWithStore(B.getRoot())->set<RegionDefaultValue>(DVM);
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}
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if (!R->isBoundable())
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return state;
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if (isa<AllocaRegion>(R) || isa<SymbolicRegion>(R) ||
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isa<ObjCObjectRegion>(R)) {
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// Invalidate the region by setting its default value to
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// conjured symbol. The type of the symbol is irrelavant.
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SVal V = ValMgr.getConjuredSymbolVal(E, Ctx.IntTy, Count);
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return setDefaultValue(state, R, V);
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}
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const TypedRegion *TR = cast<TypedRegion>(R);
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QualType T = TR->getValueType(Ctx);
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// FIXME: The code causes a crash when using RegionStore on the test case
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// 'test_invalidate_cast_int' (misc-ps.m). Consider removing it
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// permanently. Region casts are probably not too strict to handle
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// the transient interpretation of memory. Instead we can use the QualType
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// passed to 'Retrieve' and friends to determine the most current
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// interpretation of memory when it is actually used.
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#if 0
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// If the region is cast to another type, use that type.
|
|
if (const QualType *CastTy = getCastType(state, R)) {
|
|
assert(!(*CastTy)->isObjCObjectPointerType());
|
|
QualType NewT = (*CastTy)->getAs<PointerType>()->getPointeeType();
|
|
|
|
// The only exception is if the original region had a location type as its
|
|
// value type we always want to treat the region as binding to a location.
|
|
// This issue can arise when pointers are casted to integers and back.
|
|
|
|
if (!(Loc::IsLocType(T) && !Loc::IsLocType(NewT)))
|
|
T = NewT;
|
|
}
|
|
#endif
|
|
|
|
if (const RecordType *RT = T->getAsStructureType()) {
|
|
// FIXME: handle structs with default region value.
|
|
const RecordDecl *RD = RT->getDecl()->getDefinition(Ctx);
|
|
|
|
// No record definition. There is nothing we can do.
|
|
if (!RD)
|
|
return state;
|
|
|
|
// Invalidate the region by setting its default value to
|
|
// conjured symbol. The type of the symbol is irrelavant.
|
|
SVal V = ValMgr.getConjuredSymbolVal(E, Ctx.IntTy, Count);
|
|
return setDefaultValue(state, R, V);
|
|
}
|
|
|
|
if (const ArrayType *AT = Ctx.getAsArrayType(T)) {
|
|
// Set the default value of the array to conjured symbol.
|
|
SVal V = ValMgr.getConjuredSymbolVal(E, AT->getElementType(),
|
|
Count);
|
|
return setDefaultValue(state, TR, V);
|
|
}
|
|
|
|
SVal V = ValMgr.getConjuredSymbolVal(E, T, Count);
|
|
assert(SymbolManager::canSymbolicate(T) || V.isUnknown());
|
|
return Bind(state, ValMgr.makeLoc(TR), V);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// getLValueXXX methods.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// getLValueString - Returns an SVal representing the lvalue of a
|
|
/// StringLiteral. Within RegionStore a StringLiteral has an
|
|
/// associated StringRegion, and the lvalue of a StringLiteral is the
|
|
/// lvalue of that region.
|
|
SVal RegionStoreManager::getLValueString(const GRState *St,
|
|
const StringLiteral* S) {
|
|
return loc::MemRegionVal(MRMgr.getStringRegion(S));
|
|
}
|
|
|
|
/// getLValueVar - Returns an SVal that represents the lvalue of a
|
|
/// variable. Within RegionStore a variable has an associated
|
|
/// VarRegion, and the lvalue of the variable is the lvalue of that region.
|
|
SVal RegionStoreManager::getLValueVar(const GRState *St, const VarDecl* VD) {
|
|
return loc::MemRegionVal(MRMgr.getVarRegion(VD));
|
|
}
|
|
|
|
/// getLValueCompoundLiteral - Returns an SVal representing the lvalue
|
|
/// of a compound literal. Within RegionStore a compound literal
|
|
/// has an associated region, and the lvalue of the compound literal
|
|
/// is the lvalue of that region.
|
|
SVal
|
|
RegionStoreManager::getLValueCompoundLiteral(const GRState *St,
|
|
const CompoundLiteralExpr* CL) {
|
|
return loc::MemRegionVal(MRMgr.getCompoundLiteralRegion(CL));
|
|
}
|
|
|
|
SVal RegionStoreManager::getLValueIvar(const GRState *St, const ObjCIvarDecl* D,
|
|
SVal Base) {
|
|
return getLValueFieldOrIvar(St, Base, D);
|
|
}
|
|
|
|
SVal RegionStoreManager::getLValueField(const GRState *St, SVal Base,
|
|
const FieldDecl* D) {
|
|
return getLValueFieldOrIvar(St, Base, D);
|
|
}
|
|
|
|
SVal RegionStoreManager::getLValueFieldOrIvar(const GRState *St, SVal Base,
|
|
const Decl* D) {
|
|
if (Base.isUnknownOrUndef())
|
|
return Base;
|
|
|
|
Loc BaseL = cast<Loc>(Base);
|
|
const MemRegion* BaseR = 0;
|
|
|
|
switch (BaseL.getSubKind()) {
|
|
case loc::MemRegionKind:
|
|
BaseR = cast<loc::MemRegionVal>(BaseL).getRegion();
|
|
break;
|
|
|
|
case loc::GotoLabelKind:
|
|
// These are anormal cases. Flag an undefined value.
|
|
return UndefinedVal();
|
|
|
|
case loc::ConcreteIntKind:
|
|
// While these seem funny, this can happen through casts.
|
|
// FIXME: What we should return is the field offset. For example,
|
|
// add the field offset to the integer value. That way funny things
|
|
// like this work properly: &(((struct foo *) 0xa)->f)
|
|
return Base;
|
|
|
|
default:
|
|
assert(0 && "Unhandled Base.");
|
|
return Base;
|
|
}
|
|
|
|
// NOTE: We must have this check first because ObjCIvarDecl is a subclass
|
|
// of FieldDecl.
|
|
if (const ObjCIvarDecl *ID = dyn_cast<ObjCIvarDecl>(D))
|
|
return loc::MemRegionVal(MRMgr.getObjCIvarRegion(ID, BaseR));
|
|
|
|
return loc::MemRegionVal(MRMgr.getFieldRegion(cast<FieldDecl>(D), BaseR));
|
|
}
|
|
|
|
SVal RegionStoreManager::getLValueElement(const GRState *St,
|
|
QualType elementType,
|
|
SVal Base, SVal Offset) {
|
|
|
|
// If the base is an unknown or undefined value, just return it back.
|
|
// FIXME: For absolute pointer addresses, we just return that value back as
|
|
// well, although in reality we should return the offset added to that
|
|
// value.
|
|
if (Base.isUnknownOrUndef() || isa<loc::ConcreteInt>(Base))
|
|
return Base;
|
|
|
|
// Only handle integer offsets... for now.
|
|
if (!isa<nonloc::ConcreteInt>(Offset))
|
|
return UnknownVal();
|
|
|
|
const MemRegion* BaseRegion = cast<loc::MemRegionVal>(Base).getRegion();
|
|
|
|
// Pointer of any type can be cast and used as array base.
|
|
const ElementRegion *ElemR = dyn_cast<ElementRegion>(BaseRegion);
|
|
|
|
// Convert the offset to the appropriate size and signedness.
|
|
Offset = ValMgr.convertToArrayIndex(Offset);
|
|
|
|
if (!ElemR) {
|
|
//
|
|
// If the base region is not an ElementRegion, create one.
|
|
// This can happen in the following example:
|
|
//
|
|
// char *p = __builtin_alloc(10);
|
|
// p[1] = 8;
|
|
//
|
|
// Observe that 'p' binds to an AllocaRegion.
|
|
//
|
|
return loc::MemRegionVal(MRMgr.getElementRegion(elementType, Offset,
|
|
BaseRegion, getContext()));
|
|
}
|
|
|
|
SVal BaseIdx = ElemR->getIndex();
|
|
|
|
if (!isa<nonloc::ConcreteInt>(BaseIdx))
|
|
return UnknownVal();
|
|
|
|
const llvm::APSInt& BaseIdxI = cast<nonloc::ConcreteInt>(BaseIdx).getValue();
|
|
const llvm::APSInt& OffI = cast<nonloc::ConcreteInt>(Offset).getValue();
|
|
assert(BaseIdxI.isSigned());
|
|
|
|
// Compute the new index.
|
|
SVal NewIdx = nonloc::ConcreteInt(getBasicVals().getValue(BaseIdxI + OffI));
|
|
|
|
// Construct the new ElementRegion.
|
|
const MemRegion *ArrayR = ElemR->getSuperRegion();
|
|
return loc::MemRegionVal(MRMgr.getElementRegion(elementType, NewIdx, ArrayR,
|
|
getContext()));
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Extents for regions.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
SVal RegionStoreManager::getSizeInElements(const GRState *state,
|
|
const MemRegion *R) {
|
|
|
|
switch (R->getKind()) {
|
|
case MemRegion::MemSpaceRegionKind:
|
|
assert(0 && "Cannot index into a MemSpace");
|
|
return UnknownVal();
|
|
|
|
case MemRegion::CodeTextRegionKind:
|
|
// Technically this can happen if people do funny things with casts.
|
|
return UnknownVal();
|
|
|
|
// Not yet handled.
|
|
case MemRegion::AllocaRegionKind:
|
|
case MemRegion::CompoundLiteralRegionKind:
|
|
case MemRegion::ElementRegionKind:
|
|
case MemRegion::FieldRegionKind:
|
|
case MemRegion::ObjCIvarRegionKind:
|
|
case MemRegion::ObjCObjectRegionKind:
|
|
case MemRegion::SymbolicRegionKind:
|
|
return UnknownVal();
|
|
|
|
case MemRegion::StringRegionKind: {
|
|
const StringLiteral* Str = cast<StringRegion>(R)->getStringLiteral();
|
|
// We intentionally made the size value signed because it participates in
|
|
// operations with signed indices.
|
|
return ValMgr.makeIntVal(Str->getByteLength()+1, false);
|
|
}
|
|
|
|
case MemRegion::VarRegionKind: {
|
|
const VarRegion* VR = cast<VarRegion>(R);
|
|
// Get the type of the variable.
|
|
QualType T = VR->getDesugaredValueType(getContext());
|
|
|
|
// FIXME: Handle variable-length arrays.
|
|
if (isa<VariableArrayType>(T))
|
|
return UnknownVal();
|
|
|
|
if (const ConstantArrayType* CAT = dyn_cast<ConstantArrayType>(T)) {
|
|
// return the size as signed integer.
|
|
return ValMgr.makeIntVal(CAT->getSize(), false);
|
|
}
|
|
|
|
// Clients can use ordinary variables as if they were arrays. These
|
|
// essentially are arrays of size 1.
|
|
return ValMgr.makeIntVal(1, false);
|
|
}
|
|
|
|
case MemRegion::BEG_DECL_REGIONS:
|
|
case MemRegion::END_DECL_REGIONS:
|
|
case MemRegion::BEG_TYPED_REGIONS:
|
|
case MemRegion::END_TYPED_REGIONS:
|
|
assert(0 && "Infeasible region");
|
|
return UnknownVal();
|
|
}
|
|
|
|
assert(0 && "Unreachable");
|
|
return UnknownVal();
|
|
}
|
|
|
|
const GRState *RegionStoreManager::setExtent(const GRState *state,
|
|
const MemRegion *region,
|
|
SVal extent) {
|
|
return state->set<RegionExtents>(region, extent);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Location and region casting.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// ArrayToPointer - Emulates the "decay" of an array to a pointer
|
|
/// type. 'Array' represents the lvalue of the array being decayed
|
|
/// to a pointer, and the returned SVal represents the decayed
|
|
/// version of that lvalue (i.e., a pointer to the first element of
|
|
/// the array). This is called by GRExprEngine when evaluating casts
|
|
/// from arrays to pointers.
|
|
SVal RegionStoreManager::ArrayToPointer(Loc Array) {
|
|
if (!isa<loc::MemRegionVal>(Array))
|
|
return UnknownVal();
|
|
|
|
const MemRegion* R = cast<loc::MemRegionVal>(&Array)->getRegion();
|
|
const TypedRegion* ArrayR = dyn_cast<TypedRegion>(R);
|
|
|
|
if (!ArrayR)
|
|
return UnknownVal();
|
|
|
|
// Strip off typedefs from the ArrayRegion's ValueType.
|
|
QualType T = ArrayR->getValueType(getContext())->getDesugaredType();
|
|
ArrayType *AT = cast<ArrayType>(T);
|
|
T = AT->getElementType();
|
|
|
|
SVal ZeroIdx = ValMgr.makeZeroArrayIndex();
|
|
ElementRegion* ER = MRMgr.getElementRegion(T, ZeroIdx, ArrayR, getContext());
|
|
|
|
return loc::MemRegionVal(ER);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Pointer arithmetic.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
SVal RegionStoreManager::EvalBinOp(const GRState *state,
|
|
BinaryOperator::Opcode Op, Loc L, NonLoc R,
|
|
QualType resultTy) {
|
|
// Assume the base location is MemRegionVal.
|
|
if (!isa<loc::MemRegionVal>(L))
|
|
return UnknownVal();
|
|
|
|
const MemRegion* MR = cast<loc::MemRegionVal>(L).getRegion();
|
|
const ElementRegion *ER = 0;
|
|
|
|
switch (MR->getKind()) {
|
|
case MemRegion::SymbolicRegionKind: {
|
|
const SymbolicRegion *SR = cast<SymbolicRegion>(MR);
|
|
SymbolRef Sym = SR->getSymbol();
|
|
QualType T = Sym->getType(getContext());
|
|
QualType EleTy = T->getAs<PointerType>()->getPointeeType();
|
|
SVal ZeroIdx = ValMgr.makeZeroArrayIndex();
|
|
ER = MRMgr.getElementRegion(EleTy, ZeroIdx, SR, getContext());
|
|
break;
|
|
}
|
|
case MemRegion::AllocaRegionKind: {
|
|
const AllocaRegion *AR = cast<AllocaRegion>(MR);
|
|
QualType T = getContext().CharTy; // Create an ElementRegion of bytes.
|
|
QualType EleTy = T->getAs<PointerType>()->getPointeeType();
|
|
SVal ZeroIdx = ValMgr.makeZeroArrayIndex();
|
|
ER = MRMgr.getElementRegion(EleTy, ZeroIdx, AR, getContext());
|
|
break;
|
|
}
|
|
|
|
case MemRegion::ElementRegionKind: {
|
|
ER = cast<ElementRegion>(MR);
|
|
break;
|
|
}
|
|
|
|
// Not yet handled.
|
|
case MemRegion::VarRegionKind:
|
|
case MemRegion::StringRegionKind:
|
|
case MemRegion::CompoundLiteralRegionKind:
|
|
case MemRegion::FieldRegionKind:
|
|
case MemRegion::ObjCObjectRegionKind:
|
|
case MemRegion::ObjCIvarRegionKind:
|
|
return UnknownVal();
|
|
|
|
case MemRegion::CodeTextRegionKind:
|
|
// Technically this can happen if people do funny things with casts.
|
|
return UnknownVal();
|
|
|
|
case MemRegion::MemSpaceRegionKind:
|
|
assert(0 && "Cannot perform pointer arithmetic on a MemSpace");
|
|
return UnknownVal();
|
|
|
|
case MemRegion::BEG_DECL_REGIONS:
|
|
case MemRegion::END_DECL_REGIONS:
|
|
case MemRegion::BEG_TYPED_REGIONS:
|
|
case MemRegion::END_TYPED_REGIONS:
|
|
assert(0 && "Infeasible region");
|
|
return UnknownVal();
|
|
}
|
|
|
|
SVal Idx = ER->getIndex();
|
|
nonloc::ConcreteInt* Base = dyn_cast<nonloc::ConcreteInt>(&Idx);
|
|
nonloc::ConcreteInt* Offset = dyn_cast<nonloc::ConcreteInt>(&R);
|
|
|
|
// Only support concrete integer indexes for now.
|
|
if (Base && Offset) {
|
|
// FIXME: Should use SValuator here.
|
|
SVal NewIdx = Base->evalBinOp(ValMgr, Op,
|
|
cast<nonloc::ConcreteInt>(ValMgr.convertToArrayIndex(*Offset)));
|
|
const MemRegion* NewER =
|
|
MRMgr.getElementRegion(ER->getElementType(), NewIdx, ER->getSuperRegion(),
|
|
getContext());
|
|
return ValMgr.makeLoc(NewER);
|
|
}
|
|
|
|
return UnknownVal();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Loading values from regions.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static bool IsReinterpreted(QualType RTy, QualType UsedTy, ASTContext &Ctx) {
|
|
RTy = Ctx.getCanonicalType(RTy);
|
|
UsedTy = Ctx.getCanonicalType(UsedTy);
|
|
|
|
if (RTy == UsedTy)
|
|
return false;
|
|
|
|
|
|
// Recursively check the types. We basically want to see if a pointer value
|
|
// is ever reinterpreted as a non-pointer, e.g. void** and intptr_t*
|
|
// represents a reinterpretation.
|
|
if (Loc::IsLocType(RTy) && Loc::IsLocType(UsedTy)) {
|
|
const PointerType *PRTy = RTy->getAs<PointerType>();
|
|
const PointerType *PUsedTy = UsedTy->getAs<PointerType>();
|
|
|
|
return PUsedTy && PRTy &&
|
|
IsReinterpreted(PRTy->getPointeeType(),
|
|
PUsedTy->getPointeeType(), Ctx);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
SValuator::CastResult
|
|
RegionStoreManager::Retrieve(const GRState *state, Loc L, QualType T) {
|
|
|
|
assert(!isa<UnknownVal>(L) && "location unknown");
|
|
assert(!isa<UndefinedVal>(L) && "location undefined");
|
|
|
|
// FIXME: Is this even possible? Shouldn't this be treated as a null
|
|
// dereference at a higher level?
|
|
if (isa<loc::ConcreteInt>(L))
|
|
return SValuator::CastResult(state, UndefinedVal());
|
|
|
|
const MemRegion *MR = cast<loc::MemRegionVal>(L).getRegion();
|
|
|
|
// FIXME: return symbolic value for these cases.
|
|
// Example:
|
|
// void f(int* p) { int x = *p; }
|
|
// char* p = alloca();
|
|
// read(p);
|
|
// c = *p;
|
|
if (isa<AllocaRegion>(MR))
|
|
return SValuator::CastResult(state, UnknownVal());
|
|
|
|
if (isa<SymbolicRegion>(MR)) {
|
|
ASTContext &Ctx = getContext();
|
|
SVal idx = ValMgr.makeZeroArrayIndex();
|
|
assert(!T.isNull());
|
|
MR = MRMgr.getElementRegion(T, idx, MR, Ctx);
|
|
}
|
|
|
|
if (isa<CodeTextRegion>(MR))
|
|
return SValuator::CastResult(state, UnknownVal());
|
|
|
|
// FIXME: Perhaps this method should just take a 'const MemRegion*' argument
|
|
// instead of 'Loc', and have the other Loc cases handled at a higher level.
|
|
const TypedRegion *R = cast<TypedRegion>(MR);
|
|
QualType RTy = R->getValueType(getContext());
|
|
|
|
// FIXME: We should eventually handle funny addressing. e.g.:
|
|
//
|
|
// int x = ...;
|
|
// int *p = &x;
|
|
// char *q = (char*) p;
|
|
// char c = *q; // returns the first byte of 'x'.
|
|
//
|
|
// Such funny addressing will occur due to layering of regions.
|
|
|
|
#if 0
|
|
ASTContext &Ctx = getContext();
|
|
if (!T.isNull() && IsReinterpreted(RTy, T, Ctx)) {
|
|
SVal ZeroIdx = ValMgr.makeZeroArrayIndex();
|
|
R = MRMgr.getElementRegion(T, ZeroIdx, R, Ctx);
|
|
RTy = T;
|
|
assert(Ctx.getCanonicalType(RTy) ==
|
|
Ctx.getCanonicalType(R->getValueType(Ctx)));
|
|
}
|
|
#endif
|
|
|
|
if (RTy->isStructureType())
|
|
return SValuator::CastResult(state, RetrieveStruct(state, R));
|
|
|
|
if (RTy->isArrayType())
|
|
return SValuator::CastResult(state, RetrieveArray(state, R));
|
|
|
|
// FIXME: handle Vector types.
|
|
if (RTy->isVectorType())
|
|
return SValuator::CastResult(state, UnknownVal());
|
|
|
|
if (const FieldRegion* FR = dyn_cast<FieldRegion>(R))
|
|
return CastRetrievedVal(RetrieveField(state, FR), state, FR, T);
|
|
|
|
if (const ElementRegion* ER = dyn_cast<ElementRegion>(R))
|
|
return CastRetrievedVal(RetrieveElement(state, ER), state, ER, T);
|
|
|
|
if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R))
|
|
return CastRetrievedVal(RetrieveObjCIvar(state, IVR), state, IVR, T);
|
|
|
|
if (const VarRegion *VR = dyn_cast<VarRegion>(R))
|
|
return CastRetrievedVal(RetrieveVar(state, VR), state, VR, T);
|
|
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
RegionBindingsTy::data_type* V = B.lookup(R);
|
|
|
|
// Check if the region has a binding.
|
|
if (V)
|
|
return SValuator::CastResult(state, *V);
|
|
|
|
// The location does not have a bound value. This means that it has
|
|
// the value it had upon its creation and/or entry to the analyzed
|
|
// function/method. These are either symbolic values or 'undefined'.
|
|
|
|
#if HEAP_UNDEFINED
|
|
if (R->hasHeapOrStackStorage()) {
|
|
#else
|
|
if (R->hasStackStorage()) {
|
|
#endif
|
|
// All stack variables are considered to have undefined values
|
|
// upon creation. All heap allocated blocks are considered to
|
|
// have undefined values as well unless they are explicitly bound
|
|
// to specific values.
|
|
return SValuator::CastResult(state, UndefinedVal());
|
|
}
|
|
|
|
#if USE_REGION_CASTS
|
|
// If the region is already cast to another type, use that type to create the
|
|
// symbol value.
|
|
if (const QualType *p = state->get<RegionCasts>(R)) {
|
|
QualType T = *p;
|
|
RTy = T->getAs<PointerType>()->getPointeeType();
|
|
}
|
|
#endif
|
|
|
|
// All other values are symbolic.
|
|
return SValuator::CastResult(state,
|
|
ValMgr.getRegionValueSymbolValOrUnknown(R, RTy));
|
|
}
|
|
|
|
std::pair<const GRState*, const MemRegion*>
|
|
RegionStoreManager::GetLazyBinding(RegionBindingsTy B, const MemRegion *R) {
|
|
|
|
if (const nonloc::LazyCompoundVal *V =
|
|
dyn_cast_or_null<nonloc::LazyCompoundVal>(B.lookup(R)))
|
|
return std::make_pair(V->getState(), V->getRegion());
|
|
|
|
if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
|
|
const std::pair<const GRState *, const MemRegion *> &X =
|
|
GetLazyBinding(B, ER->getSuperRegion());
|
|
|
|
if (X.first)
|
|
return std::make_pair(X.first,
|
|
MRMgr.getElementRegionWithSuper(ER, X.second));
|
|
}
|
|
else if (const FieldRegion *FR = dyn_cast<FieldRegion>(R)) {
|
|
const std::pair<const GRState *, const MemRegion *> &X =
|
|
GetLazyBinding(B, FR->getSuperRegion());
|
|
|
|
if (X.first)
|
|
return std::make_pair(X.first,
|
|
MRMgr.getFieldRegionWithSuper(FR, X.second));
|
|
}
|
|
|
|
return std::make_pair((const GRState*) 0, (const MemRegion *) 0);
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveElement(const GRState* state,
|
|
const ElementRegion* R) {
|
|
// Check if the region has a binding.
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
if (const SVal* V = B.lookup(R))
|
|
return *V;
|
|
|
|
const MemRegion* superR = R->getSuperRegion();
|
|
|
|
// Check if the region is an element region of a string literal.
|
|
if (const StringRegion *StrR=dyn_cast<StringRegion>(superR)) {
|
|
const StringLiteral *Str = StrR->getStringLiteral();
|
|
SVal Idx = R->getIndex();
|
|
if (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&Idx)) {
|
|
int64_t i = CI->getValue().getSExtValue();
|
|
char c;
|
|
if (i == Str->getByteLength())
|
|
c = '\0';
|
|
else
|
|
c = Str->getStrData()[i];
|
|
return ValMgr.makeIntVal(c, getContext().CharTy);
|
|
}
|
|
}
|
|
|
|
// Special case: the current region represents a cast and it and the super
|
|
// region both have pointer types or intptr_t types. If so, perform the
|
|
// retrieve from the super region and appropriately "cast" the value.
|
|
// This is needed to support OSAtomicCompareAndSwap and friends or other
|
|
// loads that treat integers as pointers and vis versa.
|
|
if (R->getIndex().isZeroConstant()) {
|
|
if (const TypedRegion *superTR = dyn_cast<TypedRegion>(superR)) {
|
|
ASTContext &Ctx = getContext();
|
|
if (IsAnyPointerOrIntptr(superTR->getValueType(Ctx), Ctx)) {
|
|
QualType valTy = R->getValueType(Ctx);
|
|
if (IsAnyPointerOrIntptr(valTy, Ctx)) {
|
|
// Retrieve the value from the super region. This will be casted to
|
|
// valTy when we return to 'Retrieve'.
|
|
const SValuator::CastResult &cr = Retrieve(state,
|
|
loc::MemRegionVal(superR),
|
|
valTy);
|
|
return cr.getSVal();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Check if the super region has a default value.
|
|
if (const SVal *D = state->get<RegionDefaultValue>(superR)) {
|
|
if (D->hasConjuredSymbol())
|
|
return ValMgr.getRegionValueSymbolVal(R);
|
|
else
|
|
return *D;
|
|
}
|
|
|
|
// Check if the super region has a binding.
|
|
if (const SVal *V = B.lookup(superR)) {
|
|
if (SymbolRef parentSym = V->getAsSymbol())
|
|
return ValMgr.getDerivedRegionValueSymbolVal(parentSym, R);
|
|
|
|
if (V->isUnknownOrUndef())
|
|
return *V;
|
|
|
|
// Handle LazyCompoundVals below.
|
|
if (const nonloc::LazyCompoundVal *LVC =
|
|
dyn_cast<nonloc::LazyCompoundVal>(V)) {
|
|
return RetrieveElement(LVC->getState(),
|
|
MRMgr.getElementRegionWithSuper(R,
|
|
LVC->getRegion()));
|
|
}
|
|
|
|
// Other cases: give up.
|
|
return UnknownVal();
|
|
}
|
|
|
|
// Lazy binding?
|
|
const GRState *lazyBindingState = NULL;
|
|
const MemRegion *LazyBindingRegion = NULL;
|
|
llvm::tie(lazyBindingState, LazyBindingRegion) = GetLazyBinding(B, R);
|
|
|
|
if (lazyBindingState) {
|
|
assert(LazyBindingRegion && "Lazy-binding region not set");
|
|
return RetrieveElement(lazyBindingState,
|
|
cast<ElementRegion>(LazyBindingRegion));
|
|
}
|
|
|
|
// Default value cases.
|
|
#if 0
|
|
if (R->hasHeapStorage()) {
|
|
// FIXME: If the region has heap storage and we know nothing special
|
|
// about its bindings, should we instead return UnknownVal? Seems like
|
|
// we should only return UndefinedVal in the cases where we know the value
|
|
// will be undefined.
|
|
return UndefinedVal();
|
|
}
|
|
#endif
|
|
|
|
if (R->hasStackStorage() && !R->hasParametersStorage()) {
|
|
// Currently we don't reason specially about Clang-style vectors. Check
|
|
// if superR is a vector and if so return Unknown.
|
|
if (const TypedRegion *typedSuperR = dyn_cast<TypedRegion>(superR)) {
|
|
if (typedSuperR->getValueType(getContext())->isVectorType())
|
|
return UnknownVal();
|
|
}
|
|
|
|
return UndefinedVal();
|
|
}
|
|
|
|
QualType Ty = R->getValueType(getContext());
|
|
|
|
#if USE_REGION_CASTS
|
|
// If the region is already cast to another type, use that type to create the
|
|
// symbol value.
|
|
if (const QualType *p = state->get<RegionCasts>(R))
|
|
Ty = (*p)->getAs<PointerType>()->getPointeeType();
|
|
#endif
|
|
|
|
return ValMgr.getRegionValueSymbolValOrUnknown(R, Ty);
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveField(const GRState* state,
|
|
const FieldRegion* R) {
|
|
QualType Ty = R->getValueType(getContext());
|
|
|
|
// Check if the region has a binding.
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
if (const SVal* V = B.lookup(R))
|
|
return *V;
|
|
|
|
const MemRegion* superR = R->getSuperRegion();
|
|
while (superR) {
|
|
if (const SVal* D = state->get<RegionDefaultValue>(superR)) {
|
|
if (SymbolRef parentSym = D->getAsSymbol())
|
|
return ValMgr.getDerivedRegionValueSymbolVal(parentSym, R);
|
|
|
|
if (D->isZeroConstant())
|
|
return ValMgr.makeZeroVal(Ty);
|
|
|
|
if (const nonloc::LazyCompoundVal *LCV =
|
|
dyn_cast<nonloc::LazyCompoundVal>(D)) {
|
|
const FieldRegion *FR =
|
|
MRMgr.getFieldRegionWithSuper(R, LCV->getRegion());
|
|
return RetrieveField(LCV->getState(), FR);
|
|
}
|
|
|
|
if (D->isUnknown())
|
|
return *D;
|
|
|
|
assert(0 && "Unknown default value");
|
|
}
|
|
|
|
if (const SVal *V = B.lookup(superR)) {
|
|
// Handle LazyCompoundVals below.
|
|
if (isa<nonloc::CompoundVal>(*V))
|
|
break;
|
|
}
|
|
|
|
// If our super region is a field or element itself, walk up the region
|
|
// hierarchy to see if there is a default value installed in an ancestor.
|
|
if (isa<FieldRegion>(superR) || isa<ElementRegion>(superR)) {
|
|
superR = cast<SubRegion>(superR)->getSuperRegion();
|
|
continue;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
// Lazy binding?
|
|
const GRState *lazyBindingState = NULL;
|
|
const MemRegion *LazyBindingRegion = NULL;
|
|
llvm::tie(lazyBindingState, LazyBindingRegion) = GetLazyBinding(B, R);
|
|
|
|
if (lazyBindingState) {
|
|
assert(LazyBindingRegion && "Lazy-binding region not set");
|
|
return RetrieveField(lazyBindingState,
|
|
cast<FieldRegion>(LazyBindingRegion));
|
|
}
|
|
|
|
#if HEAP_UNDEFINED
|
|
// FIXME: Is this correct? Should it be UnknownVal?
|
|
if (R->hasHeapStorage())
|
|
return UndefinedVal();
|
|
#endif
|
|
|
|
if (R->hasStackStorage() && !R->hasParametersStorage())
|
|
return UndefinedVal();
|
|
|
|
#if USE_REGION_CASTS
|
|
// If the region is already cast to another type, use that type to create the
|
|
// symbol value.
|
|
if (const QualType *p = state->get<RegionCasts>(R)) {
|
|
QualType tmp = *p;
|
|
Ty = tmp->getAs<PointerType>()->getPointeeType();
|
|
}
|
|
#endif
|
|
|
|
// All other values are symbolic.
|
|
return ValMgr.getRegionValueSymbolValOrUnknown(R, Ty);
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveObjCIvar(const GRState* state,
|
|
const ObjCIvarRegion* R) {
|
|
|
|
// Check if the region has a binding.
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
|
|
if (const SVal* V = B.lookup(R))
|
|
return *V;
|
|
|
|
const MemRegion *superR = R->getSuperRegion();
|
|
|
|
// Check if the super region has a binding.
|
|
if (const SVal *V = B.lookup(superR)) {
|
|
if (SymbolRef parentSym = V->getAsSymbol())
|
|
return ValMgr.getDerivedRegionValueSymbolVal(parentSym, R);
|
|
|
|
// Other cases: give up.
|
|
return UnknownVal();
|
|
}
|
|
|
|
return RetrieveLazySymbol(state, R);
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveVar(const GRState *state,
|
|
const VarRegion *R) {
|
|
|
|
// Check if the region has a binding.
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
|
|
if (const SVal* V = B.lookup(R))
|
|
return *V;
|
|
|
|
// Lazily derive a value for the VarRegion.
|
|
const VarDecl *VD = R->getDecl();
|
|
|
|
if (VD == SelfDecl)
|
|
return loc::MemRegionVal(getSelfRegion(0));
|
|
|
|
if (R->hasGlobalsOrParametersStorage())
|
|
return ValMgr.getRegionValueSymbolValOrUnknown(R, VD->getType());
|
|
|
|
return UndefinedVal();
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveLazySymbol(const GRState *state,
|
|
const TypedRegion *R) {
|
|
|
|
QualType valTy = R->getValueType(getContext());
|
|
|
|
#if USE_REGION_CASTS
|
|
// If the region is already cast to another type, use that type to create the
|
|
// symbol value.
|
|
if (const QualType *ty = state->get<RegionCasts>(R)) {
|
|
if (const PointerType *PT = (*ty)->getAs<PointerType>()) {
|
|
QualType castTy = PT->getPointeeType();
|
|
|
|
if (!IsReinterpreted(valTy, castTy, getContext()))
|
|
valTy = castTy;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
// All other values are symbolic.
|
|
return ValMgr.getRegionValueSymbolValOrUnknown(R, valTy);
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveStruct(const GRState *state,
|
|
const TypedRegion* R){
|
|
QualType T = R->getValueType(getContext());
|
|
assert(T->isStructureType());
|
|
|
|
const RecordType* RT = T->getAsStructureType();
|
|
RecordDecl* RD = RT->getDecl();
|
|
assert(RD->isDefinition());
|
|
#if USE_EXPLICIT_COMPOUND
|
|
llvm::ImmutableList<SVal> StructVal = getBasicVals().getEmptySValList();
|
|
|
|
// FIXME: We shouldn't use a std::vector. If RecordDecl doesn't have a
|
|
// reverse iterator, we should implement one.
|
|
std::vector<FieldDecl *> Fields(RD->field_begin(), RD->field_end());
|
|
|
|
for (std::vector<FieldDecl *>::reverse_iterator Field = Fields.rbegin(),
|
|
FieldEnd = Fields.rend();
|
|
Field != FieldEnd; ++Field) {
|
|
FieldRegion* FR = MRMgr.getFieldRegion(*Field, R);
|
|
QualType FTy = (*Field)->getType();
|
|
SVal FieldValue = Retrieve(state, loc::MemRegionVal(FR), FTy).getSVal();
|
|
StructVal = getBasicVals().consVals(FieldValue, StructVal);
|
|
}
|
|
|
|
return ValMgr.makeCompoundVal(T, StructVal);
|
|
#else
|
|
return ValMgr.makeLazyCompoundVal(state, R);
|
|
#endif
|
|
}
|
|
|
|
SVal RegionStoreManager::RetrieveArray(const GRState *state,
|
|
const TypedRegion * R) {
|
|
#if USE_EXPLICIT_COMPOUND
|
|
QualType T = R->getValueType(getContext());
|
|
ConstantArrayType* CAT = cast<ConstantArrayType>(T.getTypePtr());
|
|
|
|
llvm::ImmutableList<SVal> ArrayVal = getBasicVals().getEmptySValList();
|
|
uint64_t size = CAT->getSize().getZExtValue();
|
|
for (uint64_t i = 0; i < size; ++i) {
|
|
SVal Idx = ValMgr.makeArrayIndex(i);
|
|
ElementRegion* ER = MRMgr.getElementRegion(CAT->getElementType(), Idx, R,
|
|
getContext());
|
|
QualType ETy = ER->getElementType();
|
|
SVal ElementVal = Retrieve(state, loc::MemRegionVal(ER), ETy).getSVal();
|
|
ArrayVal = getBasicVals().consVals(ElementVal, ArrayVal);
|
|
}
|
|
|
|
return ValMgr.makeCompoundVal(T, ArrayVal);
|
|
#else
|
|
assert(isa<ConstantArrayType>(R->getValueType(getContext())));
|
|
return ValMgr.makeLazyCompoundVal(state, R);
|
|
#endif
|
|
}
|
|
|
|
SValuator::CastResult RegionStoreManager::CastRetrievedVal(SVal V,
|
|
const GRState *state,
|
|
const TypedRegion *R,
|
|
QualType castTy) {
|
|
if (castTy.isNull())
|
|
return SValuator::CastResult(state, V);
|
|
|
|
ASTContext &Ctx = getContext();
|
|
return ValMgr.getSValuator().EvalCast(V, state, castTy, R->getValueType(Ctx));
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Binding values to regions.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
Store RegionStoreManager::Remove(Store store, Loc L) {
|
|
const MemRegion* R = 0;
|
|
|
|
if (isa<loc::MemRegionVal>(L))
|
|
R = cast<loc::MemRegionVal>(L).getRegion();
|
|
|
|
if (R) {
|
|
RegionBindingsTy B = GetRegionBindings(store);
|
|
return RBFactory.Remove(B, R).getRoot();
|
|
}
|
|
|
|
return store;
|
|
}
|
|
|
|
const GRState *RegionStoreManager::Bind(const GRState *state, Loc L, SVal V) {
|
|
if (isa<loc::ConcreteInt>(L))
|
|
return state;
|
|
|
|
// If we get here, the location should be a region.
|
|
const MemRegion *R = cast<loc::MemRegionVal>(L).getRegion();
|
|
|
|
// Check if the region is a struct region.
|
|
if (const TypedRegion* TR = dyn_cast<TypedRegion>(R))
|
|
if (TR->getValueType(getContext())->isStructureType())
|
|
return BindStruct(state, TR, V);
|
|
|
|
// Special case: the current region represents a cast and it and the super
|
|
// region both have pointer types or intptr_t types. If so, perform the
|
|
// bind to the super region.
|
|
// This is needed to support OSAtomicCompareAndSwap and friends or other
|
|
// loads that treat integers as pointers and vis versa.
|
|
if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
|
|
if (ER->getIndex().isZeroConstant()) {
|
|
if (const TypedRegion *superR =
|
|
dyn_cast<TypedRegion>(ER->getSuperRegion())) {
|
|
ASTContext &Ctx = getContext();
|
|
QualType superTy = superR->getValueType(Ctx);
|
|
QualType erTy = ER->getValueType(Ctx);
|
|
|
|
if (IsAnyPointerOrIntptr(superTy, Ctx) &&
|
|
IsAnyPointerOrIntptr(erTy, Ctx)) {
|
|
SValuator::CastResult cr =
|
|
ValMgr.getSValuator().EvalCast(V, state, superTy, erTy);
|
|
return Bind(cr.getState(), loc::MemRegionVal(superR), cr.getSVal());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Perform the binding.
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
return state->makeWithStore(RBFactory.Add(B, R, V).getRoot());
|
|
}
|
|
|
|
const GRState *RegionStoreManager::BindDecl(const GRState *state,
|
|
const VarDecl* VD, SVal InitVal) {
|
|
|
|
QualType T = VD->getType();
|
|
VarRegion* VR = MRMgr.getVarRegion(VD);
|
|
|
|
if (T->isArrayType())
|
|
return BindArray(state, VR, InitVal);
|
|
if (T->isStructureType())
|
|
return BindStruct(state, VR, InitVal);
|
|
|
|
return Bind(state, ValMgr.makeLoc(VR), InitVal);
|
|
}
|
|
|
|
// FIXME: this method should be merged into Bind().
|
|
const GRState *
|
|
RegionStoreManager::BindCompoundLiteral(const GRState *state,
|
|
const CompoundLiteralExpr* CL,
|
|
SVal V) {
|
|
|
|
CompoundLiteralRegion* R = MRMgr.getCompoundLiteralRegion(CL);
|
|
return Bind(state, loc::MemRegionVal(R), V);
|
|
}
|
|
|
|
const GRState *RegionStoreManager::BindArray(const GRState *state,
|
|
const TypedRegion* R,
|
|
SVal Init) {
|
|
|
|
QualType T = R->getValueType(getContext());
|
|
ConstantArrayType* CAT = cast<ConstantArrayType>(T.getTypePtr());
|
|
QualType ElementTy = CAT->getElementType();
|
|
|
|
uint64_t size = CAT->getSize().getZExtValue();
|
|
|
|
// Check if the init expr is a StringLiteral.
|
|
if (isa<loc::MemRegionVal>(Init)) {
|
|
const MemRegion* InitR = cast<loc::MemRegionVal>(Init).getRegion();
|
|
const StringLiteral* S = cast<StringRegion>(InitR)->getStringLiteral();
|
|
const char* str = S->getStrData();
|
|
unsigned len = S->getByteLength();
|
|
unsigned j = 0;
|
|
|
|
// Copy bytes from the string literal into the target array. Trailing bytes
|
|
// in the array that are not covered by the string literal are initialized
|
|
// to zero.
|
|
for (uint64_t i = 0; i < size; ++i, ++j) {
|
|
if (j >= len)
|
|
break;
|
|
|
|
SVal Idx = ValMgr.makeArrayIndex(i);
|
|
ElementRegion* ER = MRMgr.getElementRegion(ElementTy, Idx, R,
|
|
getContext());
|
|
|
|
SVal V = ValMgr.makeIntVal(str[j], sizeof(char)*8, true);
|
|
state = Bind(state, loc::MemRegionVal(ER), V);
|
|
}
|
|
|
|
return state;
|
|
}
|
|
|
|
// Handle lazy compound values.
|
|
if (nonloc::LazyCompoundVal *LCV = dyn_cast<nonloc::LazyCompoundVal>(&Init))
|
|
return CopyLazyBindings(*LCV, state, R);
|
|
|
|
// Remaining case: explicit compound values.
|
|
nonloc::CompoundVal& CV = cast<nonloc::CompoundVal>(Init);
|
|
nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
|
|
uint64_t i = 0;
|
|
|
|
for (; i < size; ++i, ++VI) {
|
|
// The init list might be shorter than the array length.
|
|
if (VI == VE)
|
|
break;
|
|
|
|
SVal Idx = ValMgr.makeArrayIndex(i);
|
|
ElementRegion* ER = MRMgr.getElementRegion(ElementTy, Idx, R, getContext());
|
|
|
|
if (CAT->getElementType()->isStructureType())
|
|
state = BindStruct(state, ER, *VI);
|
|
else
|
|
state = Bind(state, ValMgr.makeLoc(ER), *VI);
|
|
}
|
|
|
|
// If the init list is shorter than the array length, set the array default
|
|
// value.
|
|
if (i < size) {
|
|
if (ElementTy->isIntegerType()) {
|
|
SVal V = ValMgr.makeZeroVal(ElementTy);
|
|
state = setDefaultValue(state, R, V);
|
|
}
|
|
}
|
|
|
|
return state;
|
|
}
|
|
|
|
const GRState *
|
|
RegionStoreManager::BindStruct(const GRState *state, const TypedRegion* R,
|
|
SVal V) {
|
|
|
|
if (!Features.supportsFields())
|
|
return state;
|
|
|
|
QualType T = R->getValueType(getContext());
|
|
assert(T->isStructureType());
|
|
|
|
const RecordType* RT = T->getAs<RecordType>();
|
|
RecordDecl* RD = RT->getDecl();
|
|
|
|
if (!RD->isDefinition())
|
|
return state;
|
|
|
|
// Handle lazy compound values.
|
|
if (const nonloc::LazyCompoundVal *LCV = dyn_cast<nonloc::LazyCompoundVal>(&V))
|
|
return CopyLazyBindings(*LCV, state, R);
|
|
|
|
// We may get non-CompoundVal accidentally due to imprecise cast logic.
|
|
// Ignore them and kill the field values.
|
|
if (V.isUnknown() || !isa<nonloc::CompoundVal>(V))
|
|
return KillStruct(state, R);
|
|
|
|
nonloc::CompoundVal& CV = cast<nonloc::CompoundVal>(V);
|
|
nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
|
|
|
|
RecordDecl::field_iterator FI, FE;
|
|
|
|
for (FI = RD->field_begin(), FE = RD->field_end(); FI != FE; ++FI, ++VI) {
|
|
|
|
if (VI == VE)
|
|
break;
|
|
|
|
QualType FTy = (*FI)->getType();
|
|
FieldRegion* FR = MRMgr.getFieldRegion(*FI, R);
|
|
|
|
if (Loc::IsLocType(FTy) || FTy->isIntegerType())
|
|
state = Bind(state, ValMgr.makeLoc(FR), *VI);
|
|
else if (FTy->isArrayType())
|
|
state = BindArray(state, FR, *VI);
|
|
else if (FTy->isStructureType())
|
|
state = BindStruct(state, FR, *VI);
|
|
}
|
|
|
|
// There may be fewer values in the initialize list than the fields of struct.
|
|
if (FI != FE)
|
|
state = setDefaultValue(state, R, ValMgr.makeIntVal(0, false));
|
|
|
|
return state;
|
|
}
|
|
|
|
const GRState *RegionStoreManager::KillStruct(const GRState *state,
|
|
const TypedRegion* R){
|
|
|
|
// Set the default value of the struct region to "unknown".
|
|
state = state->set<RegionDefaultValue>(R, UnknownVal());
|
|
|
|
// Remove all bindings for the subregions of the struct.
|
|
Store store = state->getStore();
|
|
RegionBindingsTy B = GetRegionBindings(store);
|
|
for (RegionBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) {
|
|
const MemRegion* R = I.getKey();
|
|
if (const SubRegion* subRegion = dyn_cast<SubRegion>(R))
|
|
if (subRegion->isSubRegionOf(R))
|
|
store = Remove(store, ValMgr.makeLoc(subRegion));
|
|
}
|
|
|
|
return state->makeWithStore(store);
|
|
}
|
|
|
|
const GRState *RegionStoreManager::setDefaultValue(const GRState *state,
|
|
const MemRegion* R, SVal V) {
|
|
return state->set<RegionDefaultValue>(R, V);
|
|
}
|
|
|
|
const GRState*
|
|
RegionStoreManager::CopyLazyBindings(nonloc::LazyCompoundVal V,
|
|
const GRState *state,
|
|
const TypedRegion *R) {
|
|
|
|
// Nuke the old bindings stemming from R.
|
|
RegionBindingsTy B = GetRegionBindings(state->getStore());
|
|
RegionDefaultValue::MapTy DVM = state->get<RegionDefaultValue>();
|
|
RegionDefaultValue::MapTy::Factory &DVMFactory =
|
|
state->get_context<RegionDefaultValue>();
|
|
|
|
llvm::OwningPtr<RegionStoreSubRegionMap>
|
|
SubRegions(getRegionStoreSubRegionMap(state));
|
|
|
|
// B and DVM are updated after the call to RemoveSubRegionBindings.
|
|
RemoveSubRegionBindings(B, DVM, DVMFactory, R, *SubRegions.get());
|
|
|
|
// Now copy the bindings. This amounts to just binding 'V' to 'R'. This
|
|
// results in a zero-copy algorithm.
|
|
return state->makeWithStore(RBFactory.Add(B, R, V).getRoot());
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// State pruning.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static void UpdateLiveSymbols(SVal X, SymbolReaper& SymReaper) {
|
|
if (loc::MemRegionVal *XR = dyn_cast<loc::MemRegionVal>(&X)) {
|
|
const MemRegion *R = XR->getRegion();
|
|
|
|
while (R) {
|
|
if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
|
|
SymReaper.markLive(SR->getSymbol());
|
|
return;
|
|
}
|
|
|
|
if (const SubRegion *SR = dyn_cast<SubRegion>(R)) {
|
|
R = SR->getSuperRegion();
|
|
continue;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
for (SVal::symbol_iterator SI=X.symbol_begin(), SE=X.symbol_end();SI!=SE;++SI)
|
|
SymReaper.markLive(*SI);
|
|
}
|
|
|
|
void RegionStoreManager::RemoveDeadBindings(GRState &state, Stmt* Loc,
|
|
SymbolReaper& SymReaper,
|
|
llvm::SmallVectorImpl<const MemRegion*>& RegionRoots)
|
|
{
|
|
Store store = state.getStore();
|
|
RegionBindingsTy B = GetRegionBindings(store);
|
|
|
|
// Lazily constructed backmap from MemRegions to SubRegions.
|
|
typedef llvm::ImmutableSet<const MemRegion*> SubRegionsTy;
|
|
typedef llvm::ImmutableMap<const MemRegion*, SubRegionsTy> SubRegionsMapTy;
|
|
|
|
// The backmap from regions to subregions.
|
|
llvm::OwningPtr<RegionStoreSubRegionMap>
|
|
SubRegions(getRegionStoreSubRegionMap(&state));
|
|
|
|
// Do a pass over the regions in the store. For VarRegions we check if
|
|
// the variable is still live and if so add it to the list of live roots.
|
|
// For other regions we populate our region backmap.
|
|
llvm::SmallVector<const MemRegion*, 10> IntermediateRoots;
|
|
|
|
// Scan the direct bindings for "intermediate" roots.
|
|
for (RegionBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) {
|
|
const MemRegion *R = I.getKey();
|
|
IntermediateRoots.push_back(R);
|
|
}
|
|
|
|
// Scan the default bindings for "intermediate" roots.
|
|
RegionDefaultValue::MapTy DVM = state.get<RegionDefaultValue>();
|
|
for (RegionDefaultValue::MapTy::iterator I = DVM.begin(), E = DVM.end();
|
|
I != E; ++I) {
|
|
const MemRegion *R = I.getKey();
|
|
IntermediateRoots.push_back(R);
|
|
}
|
|
|
|
// Process the "intermediate" roots to find if they are referenced by
|
|
// real roots.
|
|
while (!IntermediateRoots.empty()) {
|
|
const MemRegion* R = IntermediateRoots.back();
|
|
IntermediateRoots.pop_back();
|
|
|
|
if (const VarRegion* VR = dyn_cast<VarRegion>(R)) {
|
|
if (SymReaper.isLive(Loc, VR->getDecl())) {
|
|
RegionRoots.push_back(VR); // This is a live "root".
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if (const SymbolicRegion* SR = dyn_cast<SymbolicRegion>(R)) {
|
|
if (SymReaper.isLive(SR->getSymbol()))
|
|
RegionRoots.push_back(SR);
|
|
continue;
|
|
}
|
|
|
|
// Add the super region for R to the worklist if it is a subregion.
|
|
if (const SubRegion* superR =
|
|
dyn_cast<SubRegion>(cast<SubRegion>(R)->getSuperRegion()))
|
|
IntermediateRoots.push_back(superR);
|
|
}
|
|
|
|
// Process the worklist of RegionRoots. This performs a "mark-and-sweep"
|
|
// of the store. We want to find all live symbols and dead regions.
|
|
llvm::SmallPtrSet<const MemRegion*, 10> Marked;
|
|
while (!RegionRoots.empty()) {
|
|
// Dequeue the next region on the worklist.
|
|
const MemRegion* R = RegionRoots.back();
|
|
RegionRoots.pop_back();
|
|
|
|
// Check if we have already processed this region.
|
|
if (Marked.count(R))
|
|
continue;
|
|
|
|
// Mark this region as processed. This is needed for termination in case
|
|
// a region is referenced more than once.
|
|
Marked.insert(R);
|
|
|
|
// Mark the symbol for any live SymbolicRegion as "live". This means we
|
|
// should continue to track that symbol.
|
|
if (const SymbolicRegion* SymR = dyn_cast<SymbolicRegion>(R))
|
|
SymReaper.markLive(SymR->getSymbol());
|
|
|
|
// Get the data binding for R (if any).
|
|
const SVal* Xptr = B.lookup(R);
|
|
if (!Xptr) {
|
|
// No direct binding? Get the default binding for R (if any).
|
|
Xptr = DVM.lookup(R);
|
|
}
|
|
|
|
// Direct or default binding?
|
|
if (Xptr) {
|
|
SVal X = *Xptr;
|
|
UpdateLiveSymbols(X, SymReaper); // Update the set of live symbols.
|
|
|
|
// If X is a region, then add it to the RegionRoots.
|
|
if (const MemRegion *RX = X.getAsRegion()) {
|
|
RegionRoots.push_back(RX);
|
|
// Mark the super region of the RX as live.
|
|
// e.g.: int x; char *y = (char*) &x; if (*y) ...
|
|
// 'y' => element region. 'x' is its super region.
|
|
if (const SubRegion *SR = dyn_cast<SubRegion>(RX)) {
|
|
RegionRoots.push_back(SR->getSuperRegion());
|
|
}
|
|
}
|
|
}
|
|
|
|
// Get the subregions of R. These are RegionRoots as well since they
|
|
// represent values that are also bound to R.
|
|
RegionStoreSubRegionMap::iterator I, E;
|
|
for (llvm::tie(I, E) = SubRegions->begin_end(R); I != E; ++I)
|
|
RegionRoots.push_back(*I);
|
|
}
|
|
|
|
// We have now scanned the store, marking reachable regions and symbols
|
|
// as live. We now remove all the regions that are dead from the store
|
|
// as well as update DSymbols with the set symbols that are now dead.
|
|
for (RegionBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) {
|
|
const MemRegion* R = I.getKey();
|
|
// If this region live? Is so, none of its symbols are dead.
|
|
if (Marked.count(R))
|
|
continue;
|
|
|
|
// Remove this dead region from the store.
|
|
store = Remove(store, ValMgr.makeLoc(R));
|
|
|
|
// Mark all non-live symbols that this region references as dead.
|
|
if (const SymbolicRegion* SymR = dyn_cast<SymbolicRegion>(R))
|
|
SymReaper.maybeDead(SymR->getSymbol());
|
|
|
|
SVal X = I.getData();
|
|
SVal::symbol_iterator SI = X.symbol_begin(), SE = X.symbol_end();
|
|
for (; SI != SE; ++SI)
|
|
SymReaper.maybeDead(*SI);
|
|
}
|
|
|
|
// Remove dead 'default' bindings.
|
|
RegionDefaultValue::MapTy NewDVM = DVM;
|
|
RegionDefaultValue::MapTy::Factory &DVMFactory =
|
|
state.get_context<RegionDefaultValue>();
|
|
|
|
for (RegionDefaultValue::MapTy::iterator I = DVM.begin(), E = DVM.end();
|
|
I != E; ++I) {
|
|
const MemRegion *R = I.getKey();
|
|
|
|
// If this region live? Is so, none of its symbols are dead.
|
|
if (Marked.count(R))
|
|
continue;
|
|
|
|
// Remove this dead region.
|
|
NewDVM = DVMFactory.Remove(NewDVM, R);
|
|
|
|
// Mark all non-live symbols that this region references as dead.
|
|
if (const SymbolicRegion* SymR = dyn_cast<SymbolicRegion>(R))
|
|
SymReaper.maybeDead(SymR->getSymbol());
|
|
|
|
SVal X = I.getData();
|
|
SVal::symbol_iterator SI = X.symbol_begin(), SE = X.symbol_end();
|
|
for (; SI != SE; ++SI)
|
|
SymReaper.maybeDead(*SI);
|
|
}
|
|
|
|
// FIXME: Do a pass over nonloc::LazyCompoundVals and the symbols
|
|
// that they reference.
|
|
|
|
// Write the store back.
|
|
state.setStore(store);
|
|
|
|
// Write the updated default bindings back.
|
|
// FIXME: Right now this involves a fetching of a persistent state.
|
|
// We can do better.
|
|
if (DVM != NewDVM)
|
|
state.setGDM(state.set<RegionDefaultValue>(NewDVM)->getGDM());
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Utility methods.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void RegionStoreManager::print(Store store, llvm::raw_ostream& OS,
|
|
const char* nl, const char *sep) {
|
|
RegionBindingsTy B = GetRegionBindings(store);
|
|
OS << "Store (direct bindings):" << nl;
|
|
|
|
for (RegionBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I)
|
|
OS << ' ' << I.getKey() << " : " << I.getData() << nl;
|
|
}
|