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//===-- GRExprEngine.h - Path-Sensitive Expression-Level Dataflow ---*- 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 a meta-engine for path-sensitive dataflow analysis that
// is built on GRCoreEngine, but provides the boilerplate to execute transfer
// functions and build the ExplodedGraph at the expression level.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_ANALYSIS_GREXPRENGINE
#define LLVM_CLANG_ANALYSIS_GREXPRENGINE
#include "clang/Checker/PathSensitive/GRSubEngine.h"
#include "clang/Checker/PathSensitive/GRCoreEngine.h"
#include "clang/Checker/PathSensitive/GRState.h"
#include "clang/Checker/PathSensitive/GRSimpleAPICheck.h"
#include "clang/Checker/PathSensitive/GRTransferFuncs.h"
#include "clang/Checker/BugReporter/BugReporter.h"
#include "clang/AST/Type.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/ExprCXX.h"
namespace clang {
class AnalysisManager;
class Checker;
class ObjCForCollectionStmt;
class GRExprEngine : public GRSubEngine {
AnalysisManager &AMgr;
GRCoreEngine CoreEngine;
/// G - the simulation graph.
ExplodedGraph& G;
/// Builder - The current GRStmtNodeBuilder which is used when building the
/// nodes for a given statement.
GRStmtNodeBuilder* Builder;
/// StateMgr - Object that manages the data for all created states.
GRStateManager StateMgr;
/// SymMgr - Object that manages the symbol information.
SymbolManager& SymMgr;
/// ValMgr - Object that manages/creates SVals.
ValueManager &ValMgr;
/// SVator - SValuator object that creates SVals from expressions.
SValuator &SVator;
/// EntryNode - The immediate predecessor node.
ExplodedNode* EntryNode;
/// CleanedState - The state for EntryNode "cleaned" of all dead
/// variables and symbols (as determined by a liveness analysis).
const GRState* CleanedState;
/// CurrentStmt - The current block-level statement.
Stmt* CurrentStmt;
// Obj-C Class Identifiers.
IdentifierInfo* NSExceptionII;
// Obj-C Selectors.
Selector* NSExceptionInstanceRaiseSelectors;
Selector RaiseSel;
llvm::OwningPtr<GRSimpleAPICheck> BatchAuditor;
typedef llvm::DenseMap<void *, unsigned> CheckerMap;
CheckerMap CheckerM;
typedef std::vector<std::pair<void *, Checker*> > CheckersOrdered;
CheckersOrdered Checkers;
/// BR - The BugReporter associated with this engine. It is important that
// this object be placed at the very end of member variables so that its
// destructor is called before the rest of the GRExprEngine is destroyed.
GRBugReporter BR;
llvm::OwningPtr<GRTransferFuncs> TF;
class CallExprWLItem {
public:
CallExpr::arg_iterator I;
ExplodedNode *N;
CallExprWLItem(const CallExpr::arg_iterator &i, ExplodedNode *n)
: I(i), N(n) {}
};
public:
GRExprEngine(AnalysisManager &mgr, GRTransferFuncs *tf);
~GRExprEngine();
void ExecuteWorkList(const LocationContext *L, unsigned Steps = 150000) {
CoreEngine.ExecuteWorkList(L, Steps);
}
/// getContext - Return the ASTContext associated with this analysis.
ASTContext& getContext() const { return G.getContext(); }
AnalysisManager &getAnalysisManager() const { return AMgr; }
SValuator &getSValuator() { return SVator; }
GRTransferFuncs& getTF() { return *TF; }
BugReporter& getBugReporter() { return BR; }
GRStmtNodeBuilder &getBuilder() { assert(Builder); return *Builder; }
// FIXME: Remove once GRTransferFuncs is no longer referenced.
void setTransferFunction(GRTransferFuncs* tf);
/// ViewGraph - Visualize the ExplodedGraph created by executing the
/// simulation.
void ViewGraph(bool trim = false);
void ViewGraph(ExplodedNode** Beg, ExplodedNode** End);
/// getInitialState - Return the initial state used for the root vertex
/// in the ExplodedGraph.
const GRState* getInitialState(const LocationContext *InitLoc);
ExplodedGraph& getGraph() { return G; }
const ExplodedGraph& getGraph() const { return G; }
template <typename CHECKER>
void registerCheck(CHECKER *check) {
unsigned entry = Checkers.size();
void *tag = CHECKER::getTag();
Checkers.push_back(std::make_pair(tag, check));
CheckerM[tag] = entry;
}
Checker *lookupChecker(void *tag) const;
template <typename CHECKER>
CHECKER *getChecker() const {
return static_cast<CHECKER*>(lookupChecker(CHECKER::getTag()));
}
void AddCheck(GRSimpleAPICheck* A, Stmt::StmtClass C);
void AddCheck(GRSimpleAPICheck* A);
/// ProcessStmt - Called by GRCoreEngine. Used to generate new successor
/// nodes by processing the 'effects' of a block-level statement.
void ProcessStmt(CFGElement E, GRStmtNodeBuilder& builder);
/// ProcessBlockEntrance - Called by GRCoreEngine when start processing
/// a CFGBlock. This method returns true if the analysis should continue
/// exploring the given path, and false otherwise.
bool ProcessBlockEntrance(CFGBlock* B, const ExplodedNode *Pred,
GRBlockCounter BC);
/// ProcessBranch - Called by GRCoreEngine. Used to generate successor
/// nodes by processing the 'effects' of a branch condition.
void ProcessBranch(Stmt* Condition, Stmt* Term, GRBranchNodeBuilder& builder);
/// ProcessIndirectGoto - Called by GRCoreEngine. Used to generate successor
/// nodes by processing the 'effects' of a computed goto jump.
void ProcessIndirectGoto(GRIndirectGotoNodeBuilder& builder);
/// ProcessSwitch - Called by GRCoreEngine. Used to generate successor
/// nodes by processing the 'effects' of a switch statement.
void ProcessSwitch(GRSwitchNodeBuilder& builder);
/// ProcessEndPath - Called by GRCoreEngine. Used to generate end-of-path
/// nodes when the control reaches the end of a function.
void ProcessEndPath(GREndPathNodeBuilder& builder);
// Generate the entry node of the callee.
void ProcessCallEnter(GRCallEnterNodeBuilder &builder);
// Generate the first post callsite node.
void ProcessCallExit(GRCallExitNodeBuilder &builder);
/// EvalAssume - Callback function invoked by the ConstraintManager when
/// making assumptions about state values.
const GRState *ProcessAssume(const GRState *state, SVal cond, bool assumption);
GRStateManager& getStateManager() { return StateMgr; }
const GRStateManager& getStateManager() const { return StateMgr; }
StoreManager& getStoreManager() { return StateMgr.getStoreManager(); }
ConstraintManager& getConstraintManager() {
return StateMgr.getConstraintManager();
}
// FIXME: Remove when we migrate over to just using ValueManager.
BasicValueFactory& getBasicVals() {
return StateMgr.getBasicVals();
}
const BasicValueFactory& getBasicVals() const {
return StateMgr.getBasicVals();
}
ValueManager &getValueManager() { return ValMgr; }
const ValueManager &getValueManager() const { return ValMgr; }
// FIXME: Remove when we migrate over to just using ValueManager.
SymbolManager& getSymbolManager() { return SymMgr; }
const SymbolManager& getSymbolManager() const { return SymMgr; }
protected:
const GRState* GetState(ExplodedNode* N) {
return N == EntryNode ? CleanedState : N->getState();
}
public:
ExplodedNode* MakeNode(ExplodedNodeSet& Dst, Stmt* S, ExplodedNode* Pred,
const GRState* St,
ProgramPoint::Kind K = ProgramPoint::PostStmtKind,
const void *tag = 0);
/// CheckerVisit - Dispatcher for performing checker-specific logic
/// at specific statements.
void CheckerVisit(Stmt *S, ExplodedNodeSet &Dst, ExplodedNodeSet &Src,
bool isPrevisit);
bool CheckerEvalCall(const CallExpr *CE,
ExplodedNodeSet &Dst,
ExplodedNode *Pred);
void CheckerEvalNilReceiver(const ObjCMessageExpr *ME,
ExplodedNodeSet &Dst,
const GRState *state,
ExplodedNode *Pred);
void CheckerVisitBind(const Stmt *AssignE, const Stmt *StoreE,
ExplodedNodeSet &Dst, ExplodedNodeSet &Src,
SVal location, SVal val, bool isPrevisit);
/// Visit - Transfer function logic for all statements. Dispatches to
/// other functions that handle specific kinds of statements.
void Visit(Stmt* S, ExplodedNode* Pred, ExplodedNodeSet& Dst);
/// VisitLValue - Evaluate the lvalue of the expression. For example, if Ex is
/// a DeclRefExpr, it evaluates to the MemRegionVal which represents its
/// storage location. Note that not all kinds of expressions has lvalue.
void VisitLValue(Expr* Ex, ExplodedNode* Pred, ExplodedNodeSet& Dst);
/// VisitArraySubscriptExpr - Transfer function for array accesses.
void VisitArraySubscriptExpr(ArraySubscriptExpr* Ex, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitAsmStmt - Transfer function logic for inline asm.
void VisitAsmStmt(AsmStmt* A, ExplodedNode* Pred, ExplodedNodeSet& Dst);
void VisitAsmStmtHelperOutputs(AsmStmt* A,
AsmStmt::outputs_iterator I,
AsmStmt::outputs_iterator E,
ExplodedNode* Pred, ExplodedNodeSet& Dst);
void VisitAsmStmtHelperInputs(AsmStmt* A,
AsmStmt::inputs_iterator I,
AsmStmt::inputs_iterator E,
ExplodedNode* Pred, ExplodedNodeSet& Dst);
/// VisitBlockExpr - Transfer function logic for BlockExprs.
void VisitBlockExpr(BlockExpr *BE, ExplodedNode *Pred, ExplodedNodeSet &Dst);
/// VisitBinaryOperator - Transfer function logic for binary operators.
void VisitBinaryOperator(BinaryOperator* B, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitCall - Transfer function for function calls.
void VisitCall(CallExpr* CE, ExplodedNode* Pred,
CallExpr::arg_iterator AI, CallExpr::arg_iterator AE,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitCast - Transfer function logic for all casts (implicit and explicit).
void VisitCast(CastExpr *CastE, Expr *Ex, ExplodedNode *Pred,
ExplodedNodeSet &Dst, bool asLValue);
/// VisitCompoundLiteralExpr - Transfer function logic for compound literals.
void VisitCompoundLiteralExpr(CompoundLiteralExpr* CL, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitDeclRefExpr - Transfer function logic for DeclRefExprs.
void VisitDeclRefExpr(DeclRefExpr* DR, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitBlockDeclRefExpr - Transfer function logic for BlockDeclRefExprs.
void VisitBlockDeclRefExpr(BlockDeclRefExpr* DR, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
void VisitCommonDeclRefExpr(Expr* DR, const NamedDecl *D,ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitDeclStmt - Transfer function logic for DeclStmts.
void VisitDeclStmt(DeclStmt* DS, ExplodedNode* Pred, ExplodedNodeSet& Dst);
/// VisitGuardedExpr - Transfer function logic for ?, __builtin_choose
void VisitGuardedExpr(Expr* Ex, Expr* L, Expr* R, ExplodedNode* Pred,
ExplodedNodeSet& Dst);
/// VisitCondInit - Transfer function for handling the initialization
/// of a condition variable in an IfStmt, SwitchStmt, etc.
void VisitCondInit(VarDecl *VD, Stmt *S, ExplodedNode *Pred,
ExplodedNodeSet& Dst);
void VisitInitListExpr(InitListExpr* E, ExplodedNode* Pred,
ExplodedNodeSet& Dst);
/// VisitLogicalExpr - Transfer function logic for '&&', '||'
void VisitLogicalExpr(BinaryOperator* B, ExplodedNode* Pred,
ExplodedNodeSet& Dst);
/// VisitMemberExpr - Transfer function for member expressions.
void VisitMemberExpr(MemberExpr* M, ExplodedNode* Pred, ExplodedNodeSet& Dst,
bool asLValue);
/// VisitObjCIvarRefExpr - Transfer function logic for ObjCIvarRefExprs.
void VisitObjCIvarRefExpr(ObjCIvarRefExpr* DR, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitObjCForCollectionStmt - Transfer function logic for
/// ObjCForCollectionStmt.
void VisitObjCForCollectionStmt(ObjCForCollectionStmt* S, ExplodedNode* Pred,
ExplodedNodeSet& Dst);
void VisitObjCForCollectionStmtAux(ObjCForCollectionStmt* S,
ExplodedNode* Pred,
ExplodedNodeSet& Dst, SVal ElementV);
/// VisitObjCMessageExpr - Transfer function for ObjC message expressions.
void VisitObjCMessageExpr(ObjCMessageExpr* ME, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
/// VisitReturnStmt - Transfer function logic for return statements.
void VisitReturnStmt(ReturnStmt* R, ExplodedNode* Pred, ExplodedNodeSet& Dst);
/// VisitOffsetOfExpr - Transfer function for offsetof.
void VisitOffsetOfExpr(OffsetOfExpr* Ex, ExplodedNode* Pred,
ExplodedNodeSet& Dst);
/// VisitSizeOfAlignOfExpr - Transfer function for sizeof.
void VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr* Ex, ExplodedNode* Pred,
ExplodedNodeSet& Dst);
/// VisitUnaryOperator - Transfer function logic for unary operators.
void VisitUnaryOperator(UnaryOperator* B, ExplodedNode* Pred,
ExplodedNodeSet& Dst, bool asLValue);
void VisitCXXThisExpr(CXXThisExpr *TE, ExplodedNode *Pred,
ExplodedNodeSet & Dst);
void VisitCXXConstructExpr(const CXXConstructExpr *E, SVal Dest,
ExplodedNode *Pred,
ExplodedNodeSet &Dst);
void VisitCXXMemberCallExpr(const CXXMemberCallExpr *MCE, ExplodedNode *Pred,
ExplodedNodeSet &Dst);
void VisitCXXNewExpr(CXXNewExpr *CNE, ExplodedNode *Pred,
ExplodedNodeSet &Dst);
void VisitCXXDeleteExpr(CXXDeleteExpr *CDE, ExplodedNode *Pred,
ExplodedNodeSet &Dst);
void VisitAggExpr(const Expr *E, SVal Dest, ExplodedNode *Pred,
ExplodedNodeSet &Dst);
/// Create a C++ temporary object for an rvalue.
void CreateCXXTemporaryObject(Expr *Ex, ExplodedNode *Pred,
ExplodedNodeSet &Dst);
/// Synthesize CXXThisRegion.
const CXXThisRegion *getCXXThisRegion(const CXXMethodDecl *MD,
const StackFrameContext *SFC);
/// Evaluate arguments with a work list algorithm.
void EvalArguments(ExprIterator AI, ExprIterator AE,
const FunctionProtoType *FnType,
ExplodedNode *Pred, ExplodedNodeSet &Dst);
/// EvalEagerlyAssume - Given the nodes in 'Src', eagerly assume symbolic
/// expressions of the form 'x != 0' and generate new nodes (stored in Dst)
/// with those assumptions.
void EvalEagerlyAssume(ExplodedNodeSet& Dst, ExplodedNodeSet& Src, Expr *Ex);
SVal EvalMinus(SVal X) {
return X.isValid() ? SVator.EvalMinus(cast<NonLoc>(X)) : X;
}
SVal EvalComplement(SVal X) {
return X.isValid() ? SVator.EvalComplement(cast<NonLoc>(X)) : X;
}
public:
SVal EvalBinOp(const GRState *state, BinaryOperator::Opcode op,
NonLoc L, NonLoc R, QualType T) {
return SVator.EvalBinOpNN(state, op, L, R, T);
}
SVal EvalBinOp(const GRState *state, BinaryOperator::Opcode op,
NonLoc L, SVal R, QualType T) {
return R.isValid() ? SVator.EvalBinOpNN(state,op,L, cast<NonLoc>(R), T) : R;
}
SVal EvalBinOp(const GRState *ST, BinaryOperator::Opcode Op,
SVal LHS, SVal RHS, QualType T) {
return SVator.EvalBinOp(ST, Op, LHS, RHS, T);
}
protected:
void EvalObjCMessageExpr(ExplodedNodeSet& Dst, ObjCMessageExpr* ME,
ExplodedNode* Pred, const GRState *state) {
assert (Builder && "GRStmtNodeBuilder must be defined.");
getTF().EvalObjCMessageExpr(Dst, *this, *Builder, ME, Pred, state);
}
const GRState* MarkBranch(const GRState* St, Stmt* Terminator,
bool branchTaken);
/// EvalBind - Handle the semantics of binding a value to a specific location.
/// This method is used by EvalStore, VisitDeclStmt, and others.
void EvalBind(ExplodedNodeSet& Dst, Stmt *AssignE,
Stmt* StoreE, ExplodedNode* Pred,
const GRState* St, SVal location, SVal Val,
bool atDeclInit = false);
public:
// FIXME: 'tag' should be removed, and a LocationContext should be used
// instead.
void EvalLoad(ExplodedNodeSet& Dst, Expr* Ex, ExplodedNode* Pred,
const GRState* St, SVal location, const void *tag = 0,
QualType LoadTy = QualType());
// FIXME: 'tag' should be removed, and a LocationContext should be used
// instead.
void EvalStore(ExplodedNodeSet& Dst, Expr* AssignE, Expr* StoreE,
ExplodedNode* Pred, const GRState* St, SVal TargetLV, SVal Val,
const void *tag = 0);
private:
void EvalLoadCommon(ExplodedNodeSet& Dst, Expr* Ex, ExplodedNode* Pred,
const GRState* St, SVal location, const void *tag,
QualType LoadTy);
// FIXME: 'tag' should be removed, and a LocationContext should be used
// instead.
void EvalLocation(ExplodedNodeSet &Dst, Stmt *S, ExplodedNode* Pred,
const GRState* St, SVal location,
const void *tag, bool isLoad);
};
} // end clang namespace
#endif
|