contrib/llvm/tools/clang/lib/StaticAnalyzer/Core/ConstraintManager.cpp

   1 //===- ConstraintManager.cpp - Constraints on symbolic values. ------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 //  This file defined the interface to manage constraints on symbolic values.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h"
  15 #include "clang/AST/Type.h"
  16 #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
  17 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
  18 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
  19 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
  20
  21 using namespace clang;
  22 using namespace ento;
  23
  24 ConstraintManager::~ConstraintManager() = default;
  25
  26 static DefinedSVal getLocFromSymbol(const ProgramStateRef &State,
  27                                     SymbolRef Sym) {
  28   const MemRegion *R =
  29       State->getStateManager().getRegionManager().getSymbolicRegion(Sym);
  30   return loc::MemRegionVal(R);
  31 }
  32
  33 ConditionTruthVal ConstraintManager::checkNull(ProgramStateRef State,
  34                                                SymbolRef Sym) {
  35   QualType Ty = Sym->getType();
  36   DefinedSVal V = Loc::isLocType(Ty) ? getLocFromSymbol(State, Sym)
  37                                      : nonloc::SymbolVal(Sym);
  38   const ProgramStatePair &P = assumeDual(State, V);
  39   if (P.first && !P.second)
  40     return ConditionTruthVal(false);
  41   if (!P.first && P.second)
  42     return ConditionTruthVal(true);
  43   return {};
  44 }