//== MemRegion.cpp - Abstract memory regions for static analysis --*- C++ -*--//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines MemRegion and its subclasses. MemRegion defines a
// partially-typed abstraction of memory useful for path-sensitive dataflow
// analyses.
//
//===----------------------------------------------------------------------===//
#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
#include "clang/AST/Attr.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/RecordLayout.h"
#include "clang/Analysis/AnalysisContext.h"
#include "clang/Analysis/Support/BumpVector.h"
#include "clang/Basic/SourceManager.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
#include "llvm/Support/raw_ostream.h"
using namespace clang;
using namespace ento;
//===----------------------------------------------------------------------===//
// MemRegion Construction.
//===----------------------------------------------------------------------===//
template<typename RegionTy> struct MemRegionManagerTrait;
template <typename RegionTy, typename A1>
RegionTy* MemRegionManager::getRegion(const A1 a1) {
const typename MemRegionManagerTrait<RegionTy>::SuperRegionTy *superRegion =
MemRegionManagerTrait<RegionTy>::getSuperRegion(*this, a1);
llvm::FoldingSetNodeID ID;
RegionTy::ProfileRegion(ID, a1, superRegion);
void *InsertPos;
RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
InsertPos));
if (!R) {
R = (RegionTy*) A.Allocate<RegionTy>();
new (R) RegionTy(a1, superRegion);
Regions.InsertNode(R, InsertPos);
}
return R;
}
template <typename RegionTy, typename A1>
RegionTy* MemRegionManager::getSubRegion(const A1 a1,
const MemRegion *superRegion) {
llvm::FoldingSetNodeID ID;
RegionTy::ProfileRegion(ID, a1, superRegion);
void *InsertPos;
RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
InsertPos));
if (!R) {
R = (RegionTy*) A.Allocate<RegionTy>();
new (R) RegionTy(a1, superRegion);
Regions.InsertNode(R, InsertPos);
}
return R;
}
template <typename RegionTy, typename A1, typename A2>
RegionTy* MemRegionManager::getRegion(const A1 a1, const A2 a2) {
const typename MemRegionManagerTrait<RegionTy>::SuperRegionTy *superRegion =
MemRegionManagerTrait<RegionTy>::getSuperRegion(*this, a1, a2);
llvm::FoldingSetNodeID ID;
RegionTy::ProfileRegion(ID, a1, a2, superRegion);
void *InsertPos;
RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
InsertPos));
if (!R) {
R = (RegionTy*) A.Allocate<RegionTy>();
new (R) RegionTy(a1, a2, superRegion);
Regions.InsertNode(R, InsertPos);
}
return R;
}
template <typename RegionTy, typename A1, typename A2>
RegionTy* MemRegionManager::getSubRegion(const A1 a1, const A2 a2,
const MemRegion *superRegion) {
llvm::FoldingSetNodeID ID;
RegionTy::ProfileRegion(ID, a1, a2, superRegion);
void *InsertPos;
RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
InsertPos));
if (!R) {
R = (RegionTy*) A.Allocate<RegionTy>();
new (R) RegionTy(a1, a2, superRegion);
Regions.InsertNode(R, InsertPos);
}
return R;
}
template <typename RegionTy, typename A1, typename A2, typename A3>
RegionTy* MemRegionManager::getSubRegion(const A1 a1, const A2 a2, const A3 a3,
const MemRegion *superRegion) {
llvm::FoldingSetNodeID ID;
RegionTy::ProfileRegion(ID, a1, a2, a3, superRegion);
void *InsertPos;
RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
InsertPos));
if (!R) {
R = (RegionTy*) A.Allocate<RegionTy>();
new (R) RegionTy(a1, a2, a3, superRegion);
Regions.InsertNode(R, InsertPos);
}
return R;
}
//===----------------------------------------------------------------------===//
// Object destruction.
//===----------------------------------------------------------------------===//
MemRegion::~MemRegion() {}
MemRegionManager::~MemRegionManager() {
// All regions and their data are BumpPtrAllocated. No need to call
// their destructors.
}
//===----------------------------------------------------------------------===//
// Basic methods.
//===----------------------------------------------------------------------===//
bool SubRegion::isSubRegionOf(const MemRegion* R) const {
const MemRegion* r = getSuperRegion();
while (r != 0) {
if (r == R)
return true;
if (const SubRegion* sr = dyn_cast<SubRegion>(r))
r = sr->getSuperRegion();
else
break;
}
return false;
}
MemRegionManager* SubRegion::getMemRegionManager() const {
const SubRegion* r = this;
do {
const MemRegion *superRegion = r->getSuperRegion();
if (const SubRegion *sr = dyn_cast<SubRegion>(superRegion)) {
r = sr;
continue;
}
return superRegion->getMemRegionManager();
} while (1);
}
const StackFrameContext *VarRegion::getStackFrame() const {
const StackSpaceRegion *SSR = dyn_cast<StackSpaceRegion>(getMemorySpace());
return SSR ? SSR->getStackFrame() : NULL;
}
//===----------------------------------------------------------------------===//
// Region extents.
//===----------------------------------------------------------------------===//
DefinedOrUnknownSVal TypedValueRegion::getExtent(SValBuilder &svalBuilder) const {
ASTContext &Ctx = svalBuilder.getContext();
QualType T = getDesugaredValueType(Ctx);
if (isa<VariableArrayType>(T))
return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
if (T->isIncompleteType())
return UnknownVal();
CharUnits size = Ctx.getTypeSizeInChars(T);
QualType sizeTy = svalBuilder.getArrayIndexType();
return svalBuilder.makeIntVal(size.getQuantity(), sizeTy);
}
DefinedOrUnknownSVal FieldRegion::getExtent(SValBuilder &svalBuilder) const {
// Force callers to deal with bitfields explicitly.
if (getDecl()->isBitField())
return UnknownVal();
DefinedOrUnknownSVal Extent = DeclRegion::getExtent(svalBuilder);
// A zero-length array at the end of a struct often stands for dynamically-
// allocated extra memory.
if (Extent.isZeroConstant()) {
QualType T = getDesugaredValueType(svalBuilder.getContext());
if (isa<ConstantArrayType>(T))
return UnknownVal();
}
return Extent;
}
DefinedOrUnknownSVal AllocaRegion::getExtent(SValBuilder &svalBuilder) const {
return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
}
DefinedOrUnknownSVal SymbolicRegion::getExtent(SValBuilder &svalBuilder) const {
return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
}
DefinedOrUnknownSVal StringRegion::getExtent(SValBuilder &svalBuilder) const {
return svalBuilder.makeIntVal(getStringLiteral()->getByteLength()+1,
svalBuilder.getArrayIndexType());
}
ObjCIvarRegion::ObjCIvarRegion(const ObjCIvarDecl *ivd, const MemRegion* sReg)
: DeclRegion(ivd, sReg, ObjCIvarRegionKind) {}
const ObjCIvarDecl *ObjCIvarRegion::getDecl() const {
return cast<ObjCIvarDecl>(D);
}
QualType ObjCIvarRegion::getValueType() const {
return getDecl()->getType();
}
QualType CXXBaseObjectRegion::getValueType() const {
return QualType(getDecl()->getTypeForDecl(), 0);
}
//===----------------------------------------------------------------------===//
// FoldingSet profiling.
//===----------------------------------------------------------------------===//
void MemSpaceRegion::Profile(llvm::FoldingSetNodeID& ID) const {
ID.AddInteger((unsigned)getKind());
}
void StackSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const {
ID.AddInteger((unsigned)getKind());
ID.AddPointer(getStackFrame());
}
void StaticGlobalSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const {
ID.AddInteger((unsigned)getKind());
ID.AddPointer(getCodeRegion());
}
void StringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const StringLiteral* Str,
const MemRegion* superRegion) {
ID.AddInteger((unsigned) StringRegionKind);
ID.AddPointer(Str);
ID.AddPointer(superRegion);
}
void ObjCStringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const ObjCStringLiteral* Str,
const MemRegion* superRegion) {
ID.AddInteger((unsigned) ObjCStringRegionKind);
ID.AddPointer(Str);
ID.AddPointer(superRegion);
}
void AllocaRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const Expr *Ex, unsigned cnt,
const MemRegion *superRegion) {
ID.AddInteger((unsigned) AllocaRegionKind);
ID.AddPointer(Ex);
ID.AddInteger(cnt);
ID.AddPointer(superRegion);
}
void AllocaRegion::Profile(llvm::FoldingSetNodeID& ID) const {
ProfileRegion(ID, Ex, Cnt, superRegion);
}
void CompoundLiteralRegion::Profile(llvm::FoldingSetNodeID& ID) const {
CompoundLiteralRegion::ProfileRegion(ID, CL, superRegion);
}
void CompoundLiteralRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const CompoundLiteralExpr *CL,
const MemRegion* superRegion) {
ID.AddInteger((unsigned) CompoundLiteralRegionKind);
ID.AddPointer(CL);
ID.AddPointer(superRegion);
}
void CXXThisRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
const PointerType *PT,
const MemRegion *sRegion) {
ID.AddInteger((unsigned) CXXThisRegionKind);
ID.AddPointer(PT);
ID.AddPointer(sRegion);
}
void CXXThisRegion::Profile(llvm::FoldingSetNodeID &ID) const {
CXXThisRegion::ProfileRegion(ID, ThisPointerTy, superRegion);
}
void ObjCIvarRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const ObjCIvarDecl *ivd,
const MemRegion* superRegion) {
DeclRegion::ProfileRegion(ID, ivd, superRegion, ObjCIvarRegionKind);
}
void DeclRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, const Decl *D,
const MemRegion* superRegion, Kind k) {
ID.AddInteger((unsigned) k);
ID.AddPointer(D);
ID.AddPointer(superRegion);
}
void DeclRegion::Profile(llvm::FoldingSetNodeID& ID) const {
DeclRegion::ProfileRegion(ID, D, superRegion, getKind());
}
void VarRegion::Profile(llvm::FoldingSetNodeID &ID) const {
VarRegion::ProfileRegion(ID, getDecl(), superRegion);
}
void SymbolicRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, SymbolRef sym,
const MemRegion *sreg) {
ID.AddInteger((unsigned) MemRegion::SymbolicRegionKind);
ID.Add(sym);
ID.AddPointer(sreg);
}
void SymbolicRegion::Profile(llvm::FoldingSetNodeID& ID) const {
SymbolicRegion::ProfileRegion(ID, sym, getSuperRegion());
}
void ElementRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
QualType ElementType, SVal Idx,
const MemRegion* superRegion) {
ID.AddInteger(MemRegion::ElementRegionKind);
ID.Add(ElementType);
ID.AddPointer(superRegion);
Idx.Profile(ID);
}
void ElementRegion::Profile(llvm::FoldingSetNodeID& ID) const {
ElementRegion::ProfileRegion(ID, ElementType, Index, superRegion);
}
void FunctionTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const NamedDecl *FD,
const MemRegion*) {
ID.AddInteger(MemRegion::FunctionTextRegionKind);
ID.AddPointer(FD);
}
void FunctionTextRegion::Profile(llvm::FoldingSetNodeID& ID) const {
FunctionTextRegion::ProfileRegion(ID, FD, superRegion);
}
void BlockTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const BlockDecl *BD, CanQualType,
const AnalysisDeclContext *AC,
const MemRegion*) {
ID.AddInteger(MemRegion::BlockTextRegionKind);
ID.AddPointer(BD);
}
void BlockTextRegion::Profile(llvm::FoldingSetNodeID& ID) const {
BlockTextRegion::ProfileRegion(ID, BD, locTy, AC, superRegion);
}
void BlockDataRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
const BlockTextRegion *BC,
const LocationContext *LC,
const MemRegion *sReg) {
ID.AddInteger(MemRegion::BlockDataRegionKind);
ID.AddPointer(BC);
ID.AddPointer(LC);
ID.AddPointer(sReg);
}
void BlockDataRegion::Profile(llvm::FoldingSetNodeID& ID) const {
BlockDataRegion::ProfileRegion(ID, BC, LC, getSuperRegion());
}
void CXXTempObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
Expr const *Ex,
const MemRegion *sReg) {
ID.AddPointer(Ex);
ID.AddPointer(sReg);
}
void CXXTempObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
ProfileRegion(ID, Ex, getSuperRegion());
}
void CXXBaseObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
const CXXRecordDecl *RD,
bool IsVirtual,
const MemRegion *SReg) {
ID.AddPointer(RD);
ID.AddBoolean(IsVirtual);
ID.AddPointer(SReg);
}
void CXXBaseObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
ProfileRegion(ID, getDecl(), isVirtual(), superRegion);
}
//===----------------------------------------------------------------------===//
// Region anchors.
//===----------------------------------------------------------------------===//
void GlobalsSpaceRegion::anchor() { }
void HeapSpaceRegion::anchor() { }
void UnknownSpaceRegion::anchor() { }
void StackLocalsSpaceRegion::anchor() { }
void StackArgumentsSpaceRegion::anchor() { }
void TypedRegion::anchor() { }
void TypedValueRegion::anchor() { }
void CodeTextRegion::anchor() { }
void SubRegion::anchor() { }
//===----------------------------------------------------------------------===//
// Region pretty-printing.
//===----------------------------------------------------------------------===//
void MemRegion::dump() const {
dumpToStream(llvm::errs());
}
std::string MemRegion::getString() const {
std::string s;
llvm::raw_string_ostream os(s);
dumpToStream(os);
return os.str();
}
void MemRegion::dumpToStream(raw_ostream &os) const {
os << "<Unknown Region>";
}
void AllocaRegion::dumpToStream(raw_ostream &os) const {
os << "alloca{" << (const void*) Ex << ',' << Cnt << '}';
}
void FunctionTextRegion::dumpToStream(raw_ostream &os) const {
os << "code{" << getDecl()->getDeclName().getAsString() << '}';
}
void BlockTextRegion::dumpToStream(raw_ostream &os) const {
os << "block_code{" << (const void*) this << '}';
}
void BlockDataRegion::dumpToStream(raw_ostream &os) const {
os << "block_data{" << BC << '}';
}
void CompoundLiteralRegion::dumpToStream(raw_ostream &os) const {
// FIXME: More elaborate pretty-printing.
os << "{ " << (const void*) CL << " }";
}
void CXXTempObjectRegion::dumpToStream(raw_ostream &os) const {
os << "temp_object{" << getValueType().getAsString() << ','
<< (const void*) Ex << '}';
}
void CXXBaseObjectRegion::dumpToStream(raw_ostream &os) const {
os << "base{" << superRegion << ',' << getDecl()->getName() << '}';
}
void CXXThisRegion::dumpToStream(raw_ostream &os) const {
os << "this";
}
void ElementRegion::dumpToStream(raw_ostream &os) const {
os << "element{" << superRegion << ','
<< Index << ',' << getElementType().getAsString() << '}';
}
void FieldRegion::dumpToStream(raw_ostream &os) const {
os << superRegion << "->" << *getDecl();
}
void ObjCIvarRegion::dumpToStream(raw_ostream &os) const {
os << "ivar{" << superRegion << ',' << *getDecl() << '}';
}
void StringRegion::dumpToStream(raw_ostream &os) const {
Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
}
void ObjCStringRegion::dumpToStream(raw_ostream &os) const {
Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
}
void SymbolicRegion::dumpToStream(raw_ostream &os) const {
os << "SymRegion{" << sym << '}';
}
void VarRegion::dumpToStream(raw_ostream &os) const {
os << *cast<VarDecl>(D);
}
void RegionRawOffset::dump() const {
dumpToStream(llvm::errs());
}
void RegionRawOffset::dumpToStream(raw_ostream &os) const {
os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}';
}
void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "StaticGlobalsMemSpace{" << CR << '}';
}
void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "GlobalInternalSpaceRegion";
}
void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "GlobalSystemSpaceRegion";
}
void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "GlobalImmutableSpaceRegion";
}
void HeapSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "HeapSpaceRegion";
}
void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "UnknownSpaceRegion";
}
void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "StackArgumentsSpaceRegion";
}
void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const {
os << "StackLocalsSpaceRegion";
}
bool MemRegion::canPrintPretty() const {
return canPrintPrettyAsExpr();
}
bool MemRegion::canPrintPrettyAsExpr() const {
return false;
}
void MemRegion::printPretty(raw_ostream &os) const {
assert(canPrintPretty() && "This region cannot be printed pretty.");
os << "'";
printPrettyAsExpr(os);
os << "'";
return;
}
void MemRegion::printPrettyAsExpr(raw_ostream &os) const {
llvm_unreachable("This region cannot be printed pretty.");
return;
}
bool VarRegion::canPrintPrettyAsExpr() const {
return true;
}
void VarRegion::printPrettyAsExpr(raw_ostream &os) const {
os << getDecl()->getName();
}
bool ObjCIvarRegion::canPrintPrettyAsExpr() const {
return true;
}
void ObjCIvarRegion::printPrettyAsExpr(raw_ostream &os) const {
os << getDecl()->getName();
}
bool FieldRegion::canPrintPretty() const {
return true;
}
bool FieldRegion::canPrintPrettyAsExpr() const {
return superRegion->canPrintPrettyAsExpr();
}
void FieldRegion::printPrettyAsExpr(raw_ostream &os) const {
assert(canPrintPrettyAsExpr());
superRegion->printPrettyAsExpr(os);
os << "." << getDecl()->getName();
}
void FieldRegion::printPretty(raw_ostream &os) const {
if (canPrintPrettyAsExpr()) {
os << "\'";
printPrettyAsExpr(os);
os << "'";
} else {
os << "field " << "\'" << getDecl()->getName() << "'";
}
return;
}
bool CXXBaseObjectRegion::canPrintPrettyAsExpr() const {
return superRegion->canPrintPrettyAsExpr();
}
void CXXBaseObjectRegion::printPrettyAsExpr(raw_ostream &os) const {
superRegion->printPrettyAsExpr(os);
}
//===----------------------------------------------------------------------===//
// MemRegionManager methods.
//===----------------------------------------------------------------------===//
template <typename REG>
const REG *MemRegionManager::LazyAllocate(REG*& region) {
if (!region) {
region = (REG*) A.Allocate<REG>();
new (region) REG(this);
}
return region;
}
template <typename REG, typename ARG>
const REG *MemRegionManager::LazyAllocate(REG*& region, ARG a) {
if (!region) {
region = (REG*) A.Allocate<REG>();
new (region) REG(this, a);
}
return region;
}
const StackLocalsSpaceRegion*
MemRegionManager::getStackLocalsRegion(const StackFrameContext *STC) {
assert(STC);
StackLocalsSpaceRegion *&R = StackLocalsSpaceRegions[STC];
if (R)
return R;
R = A.Allocate<StackLocalsSpaceRegion>();
new (R) StackLocalsSpaceRegion(this, STC);
return R;
}
const StackArgumentsSpaceRegion *
MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) {
assert(STC);
StackArgumentsSpaceRegion *&R = StackArgumentsSpaceRegions[STC];
if (R)
return R;
R = A.Allocate<StackArgumentsSpaceRegion>();
new (R) StackArgumentsSpaceRegion(this, STC);
return R;
}
const GlobalsSpaceRegion
*MemRegionManager::getGlobalsRegion(MemRegion::Kind K,
const CodeTextRegion *CR) {
if (!CR) {
if (K == MemRegion::GlobalSystemSpaceRegionKind)
return LazyAllocate(SystemGlobals);
if (K == MemRegion::GlobalImmutableSpaceRegionKind)
return LazyAllocate(ImmutableGlobals);
assert(K == MemRegion::GlobalInternalSpaceRegionKind);
return LazyAllocate(InternalGlobals);
}
assert(K == MemRegion::StaticGlobalSpaceRegionKind);
StaticGlobalSpaceRegion *&R = StaticsGlobalSpaceRegions[CR];
if (R)
return R;
R = A.Allocate<StaticGlobalSpaceRegion>();
new (R) StaticGlobalSpaceRegion(this, CR);
return R;
}
const HeapSpaceRegion *MemRegionManager::getHeapRegion() {
return LazyAllocate(heap);
}
const MemSpaceRegion *MemRegionManager::getUnknownRegion() {
return LazyAllocate(unknown);
}
const MemSpaceRegion *MemRegionManager::getCodeRegion() {
return LazyAllocate(code);
}
//===----------------------------------------------------------------------===//
// Constructing regions.
//===----------------------------------------------------------------------===//
const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){
return getSubRegion<StringRegion>(Str, getGlobalsRegion());
}
const ObjCStringRegion *
MemRegionManager::getObjCStringRegion(const ObjCStringLiteral* Str){
return getSubRegion<ObjCStringRegion>(Str, getGlobalsRegion());
}
/// Look through a chain of LocationContexts to either find the
/// StackFrameContext that matches a DeclContext, or find a VarRegion
/// for a variable captured by a block.
static llvm::PointerUnion<const StackFrameContext *, const VarRegion *>
getStackOrCaptureRegionForDeclContext(const LocationContext *LC,
const DeclContext *DC,
const VarDecl *VD) {
while (LC) {
if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) {
if (cast<DeclContext>(SFC->getDecl()) == DC)
return SFC;
}
if (const BlockInvocationContext *BC =
dyn_cast<BlockInvocationContext>(LC)) {
const BlockDataRegion *BR =
static_cast<const BlockDataRegion*>(BC->getContextData());
// FIXME: This can be made more efficient.
for (BlockDataRegion::referenced_vars_iterator
I = BR->referenced_vars_begin(),
E = BR->referenced_vars_end(); I != E; ++I) {
if (const VarRegion *VR = dyn_cast<VarRegion>(I.getOriginalRegion()))
if (VR->getDecl() == VD)
return cast<VarRegion>(I.getCapturedRegion());
}
}
LC = LC->getParent();
}
return (const StackFrameContext*)0;
}
const VarRegion* MemRegionManager::getVarRegion(const VarDecl *D,
const LocationContext *LC) {
const MemRegion *sReg = 0;
if (D->hasGlobalStorage() && !D->isStaticLocal()) {
// First handle the globals defined in system headers.
if (C.getSourceManager().isInSystemHeader(D->getLocation())) {
// Whitelist the system globals which often DO GET modified, assume the
// rest are immutable.
if (D->getName().find("errno") != StringRef::npos)
sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
else
sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
// Treat other globals as GlobalInternal unless they are constants.
} else {
QualType GQT = D->getType();
const Type *GT = GQT.getTypePtrOrNull();
// TODO: We could walk the complex types here and see if everything is
// constified.
if (GT && GQT.isConstQualified() && GT->isArithmeticType())
sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
else
sReg = getGlobalsRegion();
}
// Finally handle static locals.
} else {
// FIXME: Once we implement scope handling, we will need to properly lookup
// 'D' to the proper LocationContext.
const DeclContext *DC = D->getDeclContext();
llvm::PointerUnion<const StackFrameContext *, const VarRegion *> V =
getStackOrCaptureRegionForDeclContext(LC, DC, D);
if (V.is<const VarRegion*>())
return V.get<const VarRegion*>();
const StackFrameContext *STC = V.get<const StackFrameContext*>();
if (!STC)
sReg = getUnknownRegion();
else {
if (D->hasLocalStorage()) {
sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)
? static_cast<const MemRegion*>(getStackArgumentsRegion(STC))
: static_cast<const MemRegion*>(getStackLocalsRegion(STC));
}
else {
assert(D->isStaticLocal());
const Decl *STCD = STC->getDecl();
if (isa<FunctionDecl>(STCD) || isa<ObjCMethodDecl>(STCD))
sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
getFunctionTextRegion(cast<NamedDecl>(STCD)));
else if (const BlockDecl *BD = dyn_cast<BlockDecl>(STCD)) {
// FIXME: The fallback type here is totally bogus -- though it should
// never be queried, it will prevent uniquing with the real
// BlockTextRegion. Ideally we'd fix the AST so that we always had a
// signature.
QualType T;
if (const TypeSourceInfo *TSI = BD->getSignatureAsWritten())
T = TSI->getType();
else
T = getContext().getFunctionNoProtoType(getContext().VoidTy);
const BlockTextRegion *BTR =
getBlockTextRegion(BD, C.getCanonicalType(T),
STC->getAnalysisDeclContext());
sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
BTR);
}
else {
sReg = getGlobalsRegion();
}
}
}
}
return getSubRegion<VarRegion>(D, sReg);
}
const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
const MemRegion *superR) {
return getSubRegion<VarRegion>(D, superR);
}
const BlockDataRegion *
MemRegionManager::getBlockDataRegion(const BlockTextRegion *BC,
const LocationContext *LC) {
const MemRegion *sReg = 0;
const BlockDecl *BD = BC->getDecl();
if (!BD->hasCaptures()) {
// This handles 'static' blocks.
sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
}
else {
if (LC) {
// FIXME: Once we implement scope handling, we want the parent region
// to be the scope.
const StackFrameContext *STC = LC->getCurrentStackFrame();
assert(STC);
sReg = getStackLocalsRegion(STC);
}
else {
// We allow 'LC' to be NULL for cases where want BlockDataRegions
// without context-sensitivity.
sReg = getUnknownRegion();
}
}
return getSubRegion<BlockDataRegion>(BC, LC, sReg);
}
const CXXTempObjectRegion *
MemRegionManager::getCXXStaticTempObjectRegion(const Expr *Ex) {
return getSubRegion<CXXTempObjectRegion>(
Ex, getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind, NULL));
}
const CompoundLiteralRegion*
MemRegionManager::getCompoundLiteralRegion(const CompoundLiteralExpr *CL,
const LocationContext *LC) {
const MemRegion *sReg = 0;
if (CL->isFileScope())
sReg = getGlobalsRegion();
else {
const StackFrameContext *STC = LC->getCurrentStackFrame();
assert(STC);
sReg = getStackLocalsRegion(STC);
}
return getSubRegion<CompoundLiteralRegion>(CL, sReg);
}
const ElementRegion*
MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx,
const MemRegion* superRegion,
ASTContext &Ctx){
QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType();
llvm::FoldingSetNodeID ID;
ElementRegion::ProfileRegion(ID, T, Idx, superRegion);
void *InsertPos;
MemRegion* data = Regions.FindNodeOrInsertPos(ID, InsertPos);
ElementRegion* R = cast_or_null<ElementRegion>(data);
if (!R) {
R = (ElementRegion*) A.Allocate<ElementRegion>();
new (R) ElementRegion(T, Idx, superRegion);
Regions.InsertNode(R, InsertPos);
}
return R;
}
const FunctionTextRegion *
MemRegionManager::getFunctionTextRegion(const NamedDecl *FD) {
return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
}
const BlockTextRegion *
MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy,
AnalysisDeclContext *AC) {
return getSubRegion<BlockTextRegion>(BD, locTy, AC, getCodeRegion());
}
/// getSymbolicRegion - Retrieve or create a "symbolic" memory region.
const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) {
return getSubRegion<SymbolicRegion>(sym, getUnknownRegion());
}
const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) {
return getSubRegion<SymbolicRegion>(Sym, getHeapRegion());
}
const FieldRegion*
MemRegionManager::getFieldRegion(const FieldDecl *d,
const MemRegion* superRegion){
return getSubRegion<FieldRegion>(d, superRegion);
}
const ObjCIvarRegion*
MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d,
const MemRegion* superRegion) {
return getSubRegion<ObjCIvarRegion>(d, superRegion);
}
const CXXTempObjectRegion*
MemRegionManager::getCXXTempObjectRegion(Expr const *E,
LocationContext const *LC) {
const StackFrameContext *SFC = LC->getCurrentStackFrame();
assert(SFC);
return getSubRegion<CXXTempObjectRegion>(E, getStackLocalsRegion(SFC));
}
/// Checks whether \p BaseClass is a valid virtual or direct non-virtual base
/// class of the type of \p Super.
static bool isValidBaseClass(const CXXRecordDecl *BaseClass,
const TypedValueRegion *Super,
bool IsVirtual) {
BaseClass = BaseClass->getCanonicalDecl();
const CXXRecordDecl *Class = Super->getValueType()->getAsCXXRecordDecl();
if (!Class)
return true;
if (IsVirtual)
return Class->isVirtuallyDerivedFrom(BaseClass);
for (CXXRecordDecl::base_class_const_iterator I = Class->bases_begin(),
E = Class->bases_end();
I != E; ++I) {
if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == BaseClass)
return true;
}
return false;
}
const CXXBaseObjectRegion *
MemRegionManager::getCXXBaseObjectRegion(const CXXRecordDecl *RD,
const MemRegion *Super,
bool IsVirtual) {
if (isa<TypedValueRegion>(Super)) {
assert(isValidBaseClass(RD, dyn_cast<TypedValueRegion>(Super), IsVirtual));
(void)&isValidBaseClass;
if (IsVirtual) {
// Virtual base regions should not be layered, since the layout rules
// are different.
while (const CXXBaseObjectRegion *Base =
dyn_cast<CXXBaseObjectRegion>(Super)) {
Super = Base->getSuperRegion();
}
assert(Super && !isa<MemSpaceRegion>(Super));
}
}
return getSubRegion<CXXBaseObjectRegion>(RD, IsVirtual, Super);
}
const CXXThisRegion*
MemRegionManager::getCXXThisRegion(QualType thisPointerTy,
const LocationContext *LC) {
const StackFrameContext *STC = LC->getCurrentStackFrame();
assert(STC);
const PointerType *PT = thisPointerTy->getAs<PointerType>();
assert(PT);
return getSubRegion<CXXThisRegion>(PT, getStackArgumentsRegion(STC));
}
const AllocaRegion*
MemRegionManager::getAllocaRegion(const Expr *E, unsigned cnt,
const LocationContext *LC) {
const StackFrameContext *STC = LC->getCurrentStackFrame();
assert(STC);
return getSubRegion<AllocaRegion>(E, cnt, getStackLocalsRegion(STC));
}
const MemSpaceRegion *MemRegion::getMemorySpace() const {
const MemRegion *R = this;
const SubRegion* SR = dyn_cast<SubRegion>(this);
while (SR) {
R = SR->getSuperRegion();
SR = dyn_cast<SubRegion>(R);
}
return dyn_cast<MemSpaceRegion>(R);
}
bool MemRegion::hasStackStorage() const {
return isa<StackSpaceRegion>(getMemorySpace());
}
bool MemRegion::hasStackNonParametersStorage() const {
return isa<StackLocalsSpaceRegion>(getMemorySpace());
}
bool MemRegion::hasStackParametersStorage() const {
return isa<StackArgumentsSpaceRegion>(getMemorySpace());
}
bool MemRegion::hasGlobalsOrParametersStorage() const {
const MemSpaceRegion *MS = getMemorySpace();
return isa<StackArgumentsSpaceRegion>(MS) ||
isa<GlobalsSpaceRegion>(MS);
}
// getBaseRegion strips away all elements and fields, and get the base region
// of them.
const MemRegion *MemRegion::getBaseRegion() const {
const MemRegion *R = this;
while (true) {
switch (R->getKind()) {
case MemRegion::ElementRegionKind:
case MemRegion::FieldRegionKind:
case MemRegion::ObjCIvarRegionKind:
case MemRegion::CXXBaseObjectRegionKind:
R = cast<SubRegion>(R)->getSuperRegion();
continue;
default:
break;
}
break;
}
return R;
}
bool MemRegion::isSubRegionOf(const MemRegion *R) const {
return false;
}
//===----------------------------------------------------------------------===//
// View handling.
//===----------------------------------------------------------------------===//
const MemRegion *MemRegion::StripCasts(bool StripBaseCasts) const {
const MemRegion *R = this;
while (true) {
switch (R->getKind()) {
case ElementRegionKind: {
const ElementRegion *ER = cast<ElementRegion>(R);
if (!ER->getIndex().isZeroConstant())
return R;
R = ER->getSuperRegion();
break;
}
case CXXBaseObjectRegionKind:
if (!StripBaseCasts)
return R;
R = cast<CXXBaseObjectRegion>(R)->getSuperRegion();
break;
default:
return R;
}
}
}
const SymbolicRegion *MemRegion::getSymbolicBase() const {
const SubRegion *SubR = dyn_cast<SubRegion>(this);
while (SubR) {
if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(SubR))
return SymR;
SubR = dyn_cast<SubRegion>(SubR->getSuperRegion());
}
return 0;
}
// FIXME: Merge with the implementation of the same method in Store.cpp
static bool IsCompleteType(ASTContext &Ctx, QualType Ty) {
if (const RecordType *RT = Ty->getAs<RecordType>()) {
const RecordDecl *D = RT->getDecl();
if (!D->getDefinition())
return false;
}
return true;
}
RegionRawOffset ElementRegion::getAsArrayOffset() const {
CharUnits offset = CharUnits::Zero();
const ElementRegion *ER = this;
const MemRegion *superR = NULL;
ASTContext &C = getContext();
// FIXME: Handle multi-dimensional arrays.
while (ER) {
superR = ER->getSuperRegion();
// FIXME: generalize to symbolic offsets.
SVal index = ER->getIndex();
if (Optional<nonloc::ConcreteInt> CI = index.getAs<nonloc::ConcreteInt>()) {
// Update the offset.
int64_t i = CI->getValue().getSExtValue();
if (i != 0) {
QualType elemType = ER->getElementType();
// If we are pointing to an incomplete type, go no further.
if (!IsCompleteType(C, elemType)) {
superR = ER;
break;
}
CharUnits size = C.getTypeSizeInChars(elemType);
offset += (i * size);
}
// Go to the next ElementRegion (if any).
ER = dyn_cast<ElementRegion>(superR);
continue;
}
return NULL;
}
assert(superR && "super region cannot be NULL");
return RegionRawOffset(superR, offset);
}
/// Returns true if \p Base is an immediate base class of \p Child
static bool isImmediateBase(const CXXRecordDecl *Child,
const CXXRecordDecl *Base) {
// Note that we do NOT canonicalize the base class here, because
// ASTRecordLayout doesn't either. If that leads us down the wrong path,
// so be it; at least we won't crash.
for (CXXRecordDecl::base_class_const_iterator I = Child->bases_begin(),
E = Child->bases_end();
I != E; ++I) {
if (I->getType()->getAsCXXRecordDecl() == Base)
return true;
}
return false;
}
RegionOffset MemRegion::getAsOffset() const {
const MemRegion *R = this;
const MemRegion *SymbolicOffsetBase = 0;
int64_t Offset = 0;
while (1) {
switch (R->getKind()) {
case GenericMemSpaceRegionKind:
case StackLocalsSpaceRegionKind:
case StackArgumentsSpaceRegionKind:
case HeapSpaceRegionKind:
case UnknownSpaceRegionKind:
case StaticGlobalSpaceRegionKind:
case GlobalInternalSpaceRegionKind:
case GlobalSystemSpaceRegionKind:
case GlobalImmutableSpaceRegionKind:
// Stores can bind directly to a region space to set a default value.
assert(Offset == 0 && !SymbolicOffsetBase);
goto Finish;
case FunctionTextRegionKind:
case BlockTextRegionKind:
case BlockDataRegionKind:
// These will never have bindings, but may end up having values requested
// if the user does some strange casting.
if (Offset != 0)
SymbolicOffsetBase = R;
goto Finish;
case SymbolicRegionKind:
case AllocaRegionKind:
case CompoundLiteralRegionKind:
case CXXThisRegionKind:
case StringRegionKind:
case ObjCStringRegionKind:
case VarRegionKind:
case CXXTempObjectRegionKind:
// Usual base regions.
goto Finish;
case ObjCIvarRegionKind:
// This is a little strange, but it's a compromise between
// ObjCIvarRegions having unknown compile-time offsets (when using the
// non-fragile runtime) and yet still being distinct, non-overlapping
// regions. Thus we treat them as "like" base regions for the purposes
// of computing offsets.
goto Finish;
case CXXBaseObjectRegionKind: {
const CXXBaseObjectRegion *BOR = cast<CXXBaseObjectRegion>(R);
R = BOR->getSuperRegion();
QualType Ty;
bool RootIsSymbolic = false;
if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R)) {
Ty = TVR->getDesugaredValueType(getContext());
} else if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
// If our base region is symbolic, we don't know what type it really is.
// Pretend the type of the symbol is the true dynamic type.
// (This will at least be self-consistent for the life of the symbol.)
Ty = SR->getSymbol()->getType()->getPointeeType();
RootIsSymbolic = true;
}
const CXXRecordDecl *Child = Ty->getAsCXXRecordDecl();
if (!Child) {
// We cannot compute the offset of the base class.
SymbolicOffsetBase = R;
}
if (RootIsSymbolic) {
// Base layers on symbolic regions may not be type-correct.
// Double-check the inheritance here, and revert to a symbolic offset
// if it's invalid (e.g. due to a reinterpret_cast).
if (BOR->isVirtual()) {
if (!Child->isVirtuallyDerivedFrom(BOR->getDecl()))
SymbolicOffsetBase = R;
} else {
if (!isImmediateBase(Child, BOR->getDecl()))
SymbolicOffsetBase = R;
}
}
// Don't bother calculating precise offsets if we already have a
// symbolic offset somewhere in the chain.
if (SymbolicOffsetBase)
continue;
CharUnits BaseOffset;
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Child);
if (BOR->isVirtual())
BaseOffset = Layout.getVBaseClassOffset(BOR->getDecl());
else
BaseOffset = Layout.getBaseClassOffset(BOR->getDecl());
// The base offset is in chars, not in bits.
Offset += BaseOffset.getQuantity() * getContext().getCharWidth();
break;
}
case ElementRegionKind: {
const ElementRegion *ER = cast<ElementRegion>(R);
R = ER->getSuperRegion();
QualType EleTy = ER->getValueType();
if (!IsCompleteType(getContext(), EleTy)) {
// We cannot compute the offset of the base class.
SymbolicOffsetBase = R;
continue;
}
SVal Index = ER->getIndex();
if (Optional<nonloc::ConcreteInt> CI =
Index.getAs<nonloc::ConcreteInt>()) {
// Don't bother calculating precise offsets if we already have a
// symbolic offset somewhere in the chain.
if (SymbolicOffsetBase)
continue;
int64_t i = CI->getValue().getSExtValue();
// This type size is in bits.
Offset += i * getContext().getTypeSize(EleTy);
} else {
// We cannot compute offset for non-concrete index.
SymbolicOffsetBase = R;
}
break;
}
case FieldRegionKind: {
const FieldRegion *FR = cast<FieldRegion>(R);
R = FR->getSuperRegion();
const RecordDecl *RD = FR->getDecl()->getParent();
if (RD->isUnion() || !RD->isCompleteDefinition()) {
// We cannot compute offset for incomplete type.
// For unions, we could treat everything as offset 0, but we'd rather
// treat each field as a symbolic offset so they aren't stored on top
// of each other, since we depend on things in typed regions actually
// matching their types.
SymbolicOffsetBase = R;
}
// Don't bother calculating precise offsets if we already have a
// symbolic offset somewhere in the chain.
if (SymbolicOffsetBase)
continue;
// Get the field number.
unsigned idx = 0;
for (RecordDecl::field_iterator FI = RD->field_begin(),
FE = RD->field_end(); FI != FE; ++FI, ++idx)
if (FR->getDecl() == *FI)
break;
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
// This is offset in bits.
Offset += Layout.getFieldOffset(idx);
break;
}
}
}
Finish:
if (SymbolicOffsetBase)
return RegionOffset(SymbolicOffsetBase, RegionOffset::Symbolic);
return RegionOffset(R, Offset);
}
//===----------------------------------------------------------------------===//
// BlockDataRegion
//===----------------------------------------------------------------------===//
std::pair<const VarRegion *, const VarRegion *>
BlockDataRegion::getCaptureRegions(const VarDecl *VD) {
MemRegionManager &MemMgr = *getMemRegionManager();
const VarRegion *VR = 0;
const VarRegion *OriginalVR = 0;
if (!VD->getAttr<BlocksAttr>() && VD->hasLocalStorage()) {
VR = MemMgr.getVarRegion(VD, this);
OriginalVR = MemMgr.getVarRegion(VD, LC);
}
else {
if (LC) {
VR = MemMgr.getVarRegion(VD, LC);
OriginalVR = VR;
}
else {
VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion());
OriginalVR = MemMgr.getVarRegion(VD, LC);
}
}
return std::make_pair(VR, OriginalVR);
}
void BlockDataRegion::LazyInitializeReferencedVars() {
if (ReferencedVars)
return;
AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext();
AnalysisDeclContext::referenced_decls_iterator I, E;
llvm::tie(I, E) = AC->getReferencedBlockVars(BC->getDecl());
if (I == E) {
ReferencedVars = (void*) 0x1;
return;
}
MemRegionManager &MemMgr = *getMemRegionManager();
llvm::BumpPtrAllocator &A = MemMgr.getAllocator();
BumpVectorContext BC(A);
typedef BumpVector<const MemRegion*> VarVec;
VarVec *BV = (VarVec*) A.Allocate<VarVec>();
new (BV) VarVec(BC, E - I);
VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>();
new (BVOriginal) VarVec(BC, E - I);
for ( ; I != E; ++I) {
const VarRegion *VR = 0;
const VarRegion *OriginalVR = 0;
llvm::tie(VR, OriginalVR) = getCaptureRegions(*I);
assert(VR);
assert(OriginalVR);
BV->push_back(VR, BC);
BVOriginal->push_back(OriginalVR, BC);
}
ReferencedVars = BV;
OriginalVars = BVOriginal;
}
BlockDataRegion::referenced_vars_iterator
BlockDataRegion::referenced_vars_begin() const {
const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
BumpVector<const MemRegion*> *Vec =
static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
if (Vec == (void*) 0x1)
return BlockDataRegion::referenced_vars_iterator(0, 0);
BumpVector<const MemRegion*> *VecOriginal =
static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
return BlockDataRegion::referenced_vars_iterator(Vec->begin(),
VecOriginal->begin());
}
BlockDataRegion::referenced_vars_iterator
BlockDataRegion::referenced_vars_end() const {
const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
BumpVector<const MemRegion*> *Vec =
static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
if (Vec == (void*) 0x1)
return BlockDataRegion::referenced_vars_iterator(0, 0);
BumpVector<const MemRegion*> *VecOriginal =
static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
return BlockDataRegion::referenced_vars_iterator(Vec->end(),
VecOriginal->end());
}
const VarRegion *BlockDataRegion::getOriginalRegion(const VarRegion *R) const {
for (referenced_vars_iterator I = referenced_vars_begin(),
E = referenced_vars_end();
I != E; ++I) {
if (I.getCapturedRegion() == R)
return I.getOriginalRegion();
}
return 0;
}