contrib/llvm-project/clang/lib/StaticAnalyzer/Core/ConstraintManager.cpp

   1 //===- ConstraintManager.cpp - Constraints on symbolic values. ------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 //  This file defined the interface to manage constraints on symbolic values.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h"
  14 #include "clang/AST/Type.h"
  15 #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
  16 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
  17 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
  18 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
  19
  20 using namespace clang;
  21 using namespace ento;
  22
  23 ConstraintManager::~ConstraintManager() = default;
  24
  25 static DefinedSVal getLocFromSymbol(const ProgramStateRef &State,
  26                                     SymbolRef Sym) {
  27   const MemRegion *R =
  28       State->getStateManager().getRegionManager().getSymbolicRegion(Sym);
  29   return loc::MemRegionVal(R);
  30 }
  31
  32 ConditionTruthVal ConstraintManager::checkNull(ProgramStateRef State,
  33                                                SymbolRef Sym) {
  34   QualType Ty = Sym->getType();
  35   DefinedSVal V = Loc::isLocType(Ty) ? getLocFromSymbol(State, Sym)
  36                                      : nonloc::SymbolVal(Sym);
  37   const ProgramStatePair &P = assumeDual(State, V);
  38   if (P.first && !P.second)
  39     return ConditionTruthVal(false);
  40   if (!P.first && P.second)
  41     return ConditionTruthVal(true);
  42   return {};
  43 }