path: root/include/clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h

//== MemRegion.h - 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.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_GR_MEMREGION_H
#define LLVM_CLANG_GR_MEMREGION_H

#include "clang/AST/ASTContext.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/Decl.h"
#include "clang/AST/ExprObjC.h"
#include "clang/Basic/LLVM.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/Support/ErrorHandling.h"
#include <string>

namespace llvm {
class BumpPtrAllocator;
}

namespace clang {

class LocationContext;
class StackFrameContext;

namespace ento {

class CodeTextRegion;
class MemRegionManager;
class MemSpaceRegion;
class SValBuilder;
class SymbolicRegion;
class VarRegion;

/// Represent a region's offset within the top level base region.
class RegionOffset {
  /// The base region.
  const MemRegion *R;

  /// The bit offset within the base region. It shouldn't be negative.
  int64_t Offset;

public:
  // We're using a const instead of an enumeration due to the size required;
  // Visual Studio will only create enumerations of size int, not long long.
  static const int64_t Symbolic = INT64_MAX;

  RegionOffset() : R(0) {}
  RegionOffset(const MemRegion *r, int64_t off) : R(r), Offset(off) {}

  const MemRegion *getRegion() const { return R; }

  bool hasSymbolicOffset() const { return Offset == Symbolic; }

  int64_t getOffset() const {
    assert(!hasSymbolicOffset());
    return Offset;
  }

  bool isValid() const { return R; }
};

//===----------------------------------------------------------------------===//
// Base region classes.
//===----------------------------------------------------------------------===//

/// MemRegion - The root abstract class for all memory regions.
class MemRegion : public llvm::FoldingSetNode {
  friend class MemRegionManager;
public:
  enum Kind {
    // Memory spaces.
    GenericMemSpaceRegionKind,
    StackLocalsSpaceRegionKind,
    StackArgumentsSpaceRegionKind,
    HeapSpaceRegionKind,
    UnknownSpaceRegionKind,
    StaticGlobalSpaceRegionKind,
    GlobalInternalSpaceRegionKind,
    GlobalSystemSpaceRegionKind,
    GlobalImmutableSpaceRegionKind,
    BEG_NON_STATIC_GLOBAL_MEMSPACES = GlobalInternalSpaceRegionKind,
    END_NON_STATIC_GLOBAL_MEMSPACES