Split libAnalysis into two libraries: libAnalysis and libChecker.

(1) libAnalysis is a generic analysis library that can be used by
    Sema.  It defines the CFG, basic dataflow analysis primitives, and
    inexpensive flow-sensitive analyses (e.g. LiveVariables).

(2) libChecker contains the guts of the static analyzer, incuding the
    path-sensitive analysis engine and domain-specific checks.

Now any clients that want to use the frontend to build their own tools
don't need to link in the entire static analyzer.

This change exposes various obvious cleanups that can be made to the
layout of files and headers in libChecker.  More changes pending.  :)

This change also exposed a layering violation between AnalysisContext
and MemRegion.  BlockInvocationContext shouldn't explicitly know about
BlockDataRegions.  For now I've removed the BlockDataRegion* from
BlockInvocationContext (removing context-sensitivity; although this
wasn't used yet).  We need to have a better way to extend
BlockInvocationContext (and any LocationContext) to add
context-sensitivty.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94406 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 799 insertions, 0 deletions

diff --git a/lib/Checker/MemRegion.cpp b/lib/Checker/MemRegion.cpp
new file mode 100644
index 0000000000..1e82883a68
--- /dev/null
+++ b/lib/Checker/MemRegion.cpp
@@ -0,0 +1,799 @@
+//== 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/Analysis/AnalysisContext.h"
+#include "clang/Checker/PathSensitive/MemRegion.h"
+#include "clang/AST/CharUnits.h"
+#include "clang/AST/StmtVisitor.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// 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;
+}
+
+//===----------------------------------------------------------------------===//
+// 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 StringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
+                                 const StringLiteral* Str,
+                                 const MemRegion* superRegion) {
+  ID.AddInteger((unsigned) StringRegionKind);
+  ID.AddPointer(Str);
+  ID.AddPointer(superRegion);
+}
+
+void AllocaRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
+                                 const Expr* Ex, unsigned cnt,
+                                 const MemRegion *) {
+  ID.AddInteger((unsigned) AllocaRegionKind);
+  ID.AddPointer(Ex);
+  ID.AddInteger(cnt);
+}
+
+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 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 FunctionDecl *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 AnalysisContext *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 CXXObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
+                                    Expr const *Ex,
+                                    const MemRegion *sReg) {
+  ID.AddPointer(Ex);
+  ID.AddPointer(sReg);
+}
+
+void CXXObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
+  ProfileRegion(ID, Ex, getSuperRegion());
+}
+
+//===----------------------------------------------------------------------===//
+// 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(llvm::raw_ostream& os) const {
+  os << "<Unknown Region>";
+}
+
+void AllocaRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "alloca{" << (void*) Ex << ',' << Cnt << '}';
+}
+
+void FunctionTextRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "code{" << getDecl()->getDeclName().getAsString() << '}';
+}
+
+void BlockTextRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "block_code{" << (void*) this << '}';
+}
+
+void BlockDataRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "block_data{" << BC << '}';
+}
+
+
+void CompoundLiteralRegion::dumpToStream(llvm::raw_ostream& os) const {
+  // FIXME: More elaborate pretty-printing.
+  os << "{ " << (void*) CL <<  " }";
+}
+
+void CXXThisRegion::dumpToStream(llvm::raw_ostream &os) const {
+  os << "this";
+}
+
+void ElementRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "element{" << superRegion << ','
+     << Index << ',' << getElementType().getAsString() << '}';
+}
+
+void FieldRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << superRegion << "->" << getDecl()->getNameAsString();
+}
+
+void ObjCIvarRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "ivar{" << superRegion << ',' << getDecl()->getNameAsString() << '}';
+}
+
+void StringRegion::dumpToStream(llvm::raw_ostream& os) const {
+  Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOptions()));
+}
+
+void SymbolicRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << "SymRegion{" << sym << '}';
+}
+
+void VarRegion::dumpToStream(llvm::raw_ostream& os) const {
+  os << cast<VarDecl>(D)->getNameAsString();
+}
+
+void RegionRawOffset::dump() const {
+  dumpToStream(llvm::errs());
+}
+
+void RegionRawOffset::dumpToStream(llvm::raw_ostream& os) const {
+  os << "raw_offset{" << getRegion() << ',' << getByteOffset() << '}';
+}
+
+//===----------------------------------------------------------------------===//
+// 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);
+  if (STC == cachedStackLocalsFrame)
+    return cachedStackLocalsRegion;
+  cachedStackLocalsFrame = STC;
+  return LazyAllocate(cachedStackLocalsRegion, STC);
+}
+
+const StackArgumentsSpaceRegion *
+MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) {
+  assert(STC);
+  if (STC == cachedStackArgumentsFrame)
+    return cachedStackArgumentsRegion;
+  
+  cachedStackArgumentsFrame = STC;
+  return LazyAllocate(cachedStackArgumentsRegion, STC);
+}
+
+const GlobalsSpaceRegion *MemRegionManager::getGlobalsRegion() {
+  return LazyAllocate(globals);
+}
+
+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 VarRegion* MemRegionManager::getVarRegion(const VarDecl *D,
+                                                const LocationContext *LC) {
+  const MemRegion *sReg = 0;
+
+  if (D->hasLocalStorage()) {    
+    // FIXME: Once we implement scope handling, we will need to properly lookup
+    // 'D' to the proper LocationContext.
+    const DeclContext *DC = D->getDeclContext();
+    const StackFrameContext *STC = LC->getStackFrameForDeclContext(DC);
+
+    if (!STC)
+      sReg = getUnknownRegion();
+    else {
+      sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)
+            ? static_cast<const MemRegion*>(getStackArgumentsRegion(STC))
+            : static_cast<const MemRegion*>(getStackLocalsRegion(STC));
+    }
+  }
+  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;
+  
+  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 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, SVal Idx,
+                                   const MemRegion* superRegion,
+                                   ASTContext& Ctx){
+
+  QualType T = Ctx.getCanonicalType(elementType);
+
+  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 FunctionDecl *FD) {
+  return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
+}
+
+const BlockTextRegion *
+MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy,
+                                     AnalysisContext *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 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 CXXObjectRegion*
+MemRegionManager::getCXXObjectRegion(Expr const *E,
+                                     LocationContext const *LC) {
+  const StackFrameContext *SFC = LC->getCurrentStackFrame();
+  assert(SFC);
+  return getSubRegion<CXXObjectRegion>(E, getStackLocalsRegion(SFC));
+}
+
+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) {
+    if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+      R = ER->getSuperRegion();
+      continue;
+    }
+    if (const FieldRegion *FR = dyn_cast<FieldRegion>(R)) {
+      R = FR->getSuperRegion();
+      continue;
+    }
+    break;
+  }
+  return R;
+}
+
+//===----------------------------------------------------------------------===//
+// View handling.
+//===----------------------------------------------------------------------===//
+
+const MemRegion *MemRegion::StripCasts() const {
+  const MemRegion *R = this;
+  while (true) {
+    if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+      // FIXME: generalize.  Essentially we want to strip away ElementRegions
+      // that were layered on a symbolic region because of casts.  We only
+      // want to strip away ElementRegions, however, where the index is 0.
+      SVal index = ER->getIndex();
+      if (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&index)) {
+        if (CI->getValue().getSExtValue() == 0) {
+          R = ER->getSuperRegion();
+          continue;
+        }
+      }
+    }
+    break;
+  }
+  return R;
+}
+
+// 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(Ctx))
+      return false;
+  }
+
+  return true;
+}
+
+RegionRawOffset ElementRegion::getAsRawOffset() 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 (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&index)) {
+      // 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.getQuantity());
+}
+
+//===----------------------------------------------------------------------===//
+// BlockDataRegion
+//===----------------------------------------------------------------------===//
+
+void BlockDataRegion::LazyInitializeReferencedVars() {
+  if (ReferencedVars)
+    return;
+
+  AnalysisContext *AC = getCodeRegion()->getAnalysisContext();
+  AnalysisContext::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);
+  
+  for ( ; I != E; ++I) {
+    const VarDecl *VD = *I;
+    const VarRegion *VR = 0;
+    
+    if (!VD->getAttr<BlocksAttr>())
+      VR = MemMgr.getVarRegion(VD, this);
+    else {
+      if (LC)
+        VR = MemMgr.getVarRegion(VD, LC);
+      else {
+        VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion());
+      }
+    }
+    
+    assert(VR);
+    BV->push_back(VR, BC);
+  }
+  
+  ReferencedVars = BV;
+}
+
+BlockDataRegion::referenced_vars_iterator
+BlockDataRegion::referenced_vars_begin() const {
+  const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
+
+  BumpVector<const MemRegion*> *Vec =
+    static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
+  
+  return BlockDataRegion::referenced_vars_iterator(Vec == (void*) 0x1 ?
+                                                   NULL : Vec->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);
+  
+  return BlockDataRegion::referenced_vars_iterator(Vec == (void*) 0x1 ?
+                                                   NULL : Vec->end());
+}