forked from OSchip/llvm-project
881 lines
27 KiB
C++
881 lines
27 KiB
C++
//==- CoreEngine.cpp - Path-Sensitive Dataflow Engine ------------*- C++ -*-//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines a generic engine for intraprocedural, path-sensitive,
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// dataflow analysis via graph reachability engine.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h"
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#include "clang/AST/Expr.h"
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#include "clang/AST/ExprCXX.h"
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#include "clang/AST/StmtCXX.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/ADT/DenseSet.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/Support/Casting.h"
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#include "llvm/ADT/PriorityQueue.h"
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using namespace clang;
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using namespace ento;
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#define DEBUG_TYPE "CoreEngine"
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STATISTIC(NumSteps,
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"The # of steps executed.");
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STATISTIC(NumReachedMaxSteps,
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"The # of times we reached the max number of steps.");
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STATISTIC(NumPathsExplored,
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"The # of paths explored by the analyzer.");
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STATISTIC(MaxQueueSize, "Maximum size of the worklist");
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STATISTIC(MaxReachableSize, "Maximum size of auxiliary worklist set");
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//===----------------------------------------------------------------------===//
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// Worklist classes for exploration of reachable states.
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//===----------------------------------------------------------------------===//
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namespace {
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class DFS : public WorkList {
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SmallVector<WorkListUnit,20> Stack;
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public:
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bool hasWork() const override {
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return !Stack.empty();
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}
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void enqueue(const WorkListUnit& U) override {
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Stack.push_back(U);
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}
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WorkListUnit dequeue() override {
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assert (!Stack.empty());
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const WorkListUnit& U = Stack.back();
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Stack.pop_back(); // This technically "invalidates" U, but we are fine.
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return U;
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}
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};
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class BFS : public WorkList {
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std::deque<WorkListUnit> Queue;
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public:
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bool hasWork() const override {
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return !Queue.empty();
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}
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void enqueue(const WorkListUnit& U) override {
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Queue.push_back(U);
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}
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WorkListUnit dequeue() override {
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WorkListUnit U = Queue.front();
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Queue.pop_front();
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return U;
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}
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};
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} // end anonymous namespace
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// Place the dstor for WorkList here because it contains virtual member
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// functions, and we the code for the dstor generated in one compilation unit.
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WorkList::~WorkList() {}
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std::unique_ptr<WorkList> WorkList::makeDFS() {
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return llvm::make_unique<DFS>();
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}
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std::unique_ptr<WorkList> WorkList::makeBFS() {
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return llvm::make_unique<BFS>();
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}
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namespace {
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class BFSBlockDFSContents : public WorkList {
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std::deque<WorkListUnit> Queue;
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SmallVector<WorkListUnit,20> Stack;
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public:
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bool hasWork() const override {
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return !Queue.empty() || !Stack.empty();
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}
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void enqueue(const WorkListUnit& U) override {
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if (U.getNode()->getLocation().getAs<BlockEntrance>())
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Queue.push_front(U);
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else
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Stack.push_back(U);
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}
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WorkListUnit dequeue() override {
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// Process all basic blocks to completion.
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if (!Stack.empty()) {
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const WorkListUnit& U = Stack.back();
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Stack.pop_back(); // This technically "invalidates" U, but we are fine.
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return U;
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}
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assert(!Queue.empty());
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// Don't use const reference. The subsequent pop_back() might make it
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// unsafe.
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WorkListUnit U = Queue.front();
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Queue.pop_front();
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return U;
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}
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};
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} // end anonymous namespace
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std::unique_ptr<WorkList> WorkList::makeBFSBlockDFSContents() {
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return llvm::make_unique<BFSBlockDFSContents>();
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}
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namespace {
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class UnexploredFirstStack : public WorkList {
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/// Stack of nodes known to have statements we have not traversed yet.
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SmallVector<WorkListUnit, 20> StackUnexplored;
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/// Stack of all other nodes.
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SmallVector<WorkListUnit, 20> StackOthers;
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typedef unsigned BlockID;
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typedef std::pair<BlockID, const StackFrameContext *> LocIdentifier;
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llvm::DenseSet<LocIdentifier> Reachable;
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public:
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bool hasWork() const override {
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return !(StackUnexplored.empty() && StackOthers.empty());
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}
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void enqueue(const WorkListUnit &U) override {
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const ExplodedNode *N = U.getNode();
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auto BE = N->getLocation().getAs<BlockEntrance>();
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if (!BE) {
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// Assume the choice of the order of the preceeding block entrance was
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// correct.
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StackUnexplored.push_back(U);
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} else {
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LocIdentifier LocId = std::make_pair(
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BE->getBlock()->getBlockID(), N->getStackFrame());
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auto InsertInfo = Reachable.insert(LocId);
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if (InsertInfo.second) {
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StackUnexplored.push_back(U);
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} else {
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StackOthers.push_back(U);
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}
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}
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MaxReachableSize.updateMax(Reachable.size());
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MaxQueueSize.updateMax(StackUnexplored.size() + StackOthers.size());
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}
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WorkListUnit dequeue() override {
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if (!StackUnexplored.empty()) {
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WorkListUnit &U = StackUnexplored.back();
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StackUnexplored.pop_back();
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return U;
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} else {
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WorkListUnit &U = StackOthers.back();
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StackOthers.pop_back();
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return U;
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}
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}
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};
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} // end anonymous namespace
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std::unique_ptr<WorkList> WorkList::makeUnexploredFirst() {
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return llvm::make_unique<UnexploredFirstStack>();
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}
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class UnexploredFirstPriorityQueue : public WorkList {
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typedef unsigned BlockID;
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typedef std::pair<BlockID, const StackFrameContext *> LocIdentifier;
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// How many times each location was visited.
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// Is signed because we negate it later in order to have a reversed
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// comparison.
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typedef llvm::DenseMap<LocIdentifier, int> VisitedTimesMap;
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// Compare by number of times the location was visited first (negated
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// to prefer less often visited locations), then by insertion time (prefer
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// expanding nodes inserted sooner first).
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typedef std::pair<int, unsigned long> QueuePriority;
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typedef std::pair<WorkListUnit, QueuePriority> QueueItem;
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struct ExplorationComparator {
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bool operator() (const QueueItem &LHS, const QueueItem &RHS) {
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return LHS.second < RHS.second;
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}
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};
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// Number of inserted nodes, used to emulate DFS ordering in the priority
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// queue when insertions are equal.
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unsigned long Counter = 0;
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// Number of times a current location was reached.
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VisitedTimesMap NumReached;
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// The top item is the largest one.
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llvm::PriorityQueue<QueueItem, std::vector<QueueItem>, ExplorationComparator>
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queue;
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public:
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bool hasWork() const override {
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return !queue.empty();
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}
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void enqueue(const WorkListUnit &U) override {
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const ExplodedNode *N = U.getNode();
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unsigned NumVisited = 0;
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if (auto BE = N->getLocation().getAs<BlockEntrance>()) {
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LocIdentifier LocId = std::make_pair(
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BE->getBlock()->getBlockID(), N->getStackFrame());
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NumVisited = NumReached[LocId]++;
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}
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queue.push(std::make_pair(U, std::make_pair(-NumVisited, ++Counter)));
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}
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WorkListUnit dequeue() override {
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QueueItem U = queue.top();
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queue.pop();
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return U.first;
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}
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};
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std::unique_ptr<WorkList> WorkList::makeUnexploredFirstPriorityQueue() {
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return llvm::make_unique<UnexploredFirstPriorityQueue>();
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}
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//===----------------------------------------------------------------------===//
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// Core analysis engine.
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//===----------------------------------------------------------------------===//
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static std::unique_ptr<WorkList> generateWorkList(AnalyzerOptions &Opts) {
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switch (Opts.getExplorationStrategy()) {
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case AnalyzerOptions::ExplorationStrategyKind::DFS:
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return WorkList::makeDFS();
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case AnalyzerOptions::ExplorationStrategyKind::BFS:
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return WorkList::makeBFS();
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case AnalyzerOptions::ExplorationStrategyKind::BFSBlockDFSContents:
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return WorkList::makeBFSBlockDFSContents();
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case AnalyzerOptions::ExplorationStrategyKind::UnexploredFirst:
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return WorkList::makeUnexploredFirst();
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case AnalyzerOptions::ExplorationStrategyKind::UnexploredFirstQueue:
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return WorkList::makeUnexploredFirstPriorityQueue();
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default:
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llvm_unreachable("Unexpected case");
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}
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}
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CoreEngine::CoreEngine(SubEngine &subengine,
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FunctionSummariesTy *FS,
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AnalyzerOptions &Opts) : SubEng(subengine),
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WList(generateWorkList(Opts)),
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BCounterFactory(G.getAllocator()),
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FunctionSummaries(FS) {}
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/// ExecuteWorkList - Run the worklist algorithm for a maximum number of steps.
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bool CoreEngine::ExecuteWorkList(const LocationContext *L, unsigned Steps,
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ProgramStateRef InitState) {
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if (G.num_roots() == 0) { // Initialize the analysis by constructing
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// the root if none exists.
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const CFGBlock *Entry = &(L->getCFG()->getEntry());
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assert (Entry->empty() &&
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"Entry block must be empty.");
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assert (Entry->succ_size() == 1 &&
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"Entry block must have 1 successor.");
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// Mark the entry block as visited.
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FunctionSummaries->markVisitedBasicBlock(Entry->getBlockID(),
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L->getDecl(),
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L->getCFG()->getNumBlockIDs());
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// Get the solitary successor.
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const CFGBlock *Succ = *(Entry->succ_begin());
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// Construct an edge representing the
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// starting location in the function.
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BlockEdge StartLoc(Entry, Succ, L);
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// Set the current block counter to being empty.
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WList->setBlockCounter(BCounterFactory.GetEmptyCounter());
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if (!InitState)
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InitState = SubEng.getInitialState(L);
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bool IsNew;
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ExplodedNode *Node = G.getNode(StartLoc, InitState, false, &IsNew);
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assert (IsNew);
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G.addRoot(Node);
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NodeBuilderContext BuilderCtx(*this, StartLoc.getDst(), Node);
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ExplodedNodeSet DstBegin;
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SubEng.processBeginOfFunction(BuilderCtx, Node, DstBegin, StartLoc);
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enqueue(DstBegin);
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}
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// Check if we have a steps limit
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bool UnlimitedSteps = Steps == 0;
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// Cap our pre-reservation in the event that the user specifies
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// a very large number of maximum steps.
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const unsigned PreReservationCap = 4000000;
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if(!UnlimitedSteps)
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G.reserve(std::min(Steps,PreReservationCap));
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while (WList->hasWork()) {
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if (!UnlimitedSteps) {
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if (Steps == 0) {
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NumReachedMaxSteps++;
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break;
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}
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--Steps;
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}
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NumSteps++;
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const WorkListUnit& WU = WList->dequeue();
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// Set the current block counter.
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WList->setBlockCounter(WU.getBlockCounter());
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// Retrieve the node.
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ExplodedNode *Node = WU.getNode();
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dispatchWorkItem(Node, Node->getLocation(), WU);
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}
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SubEng.processEndWorklist(hasWorkRemaining());
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return WList->hasWork();
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}
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void CoreEngine::dispatchWorkItem(ExplodedNode* Pred, ProgramPoint Loc,
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const WorkListUnit& WU) {
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// Dispatch on the location type.
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switch (Loc.getKind()) {
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case ProgramPoint::BlockEdgeKind:
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HandleBlockEdge(Loc.castAs<BlockEdge>(), Pred);
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break;
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case ProgramPoint::BlockEntranceKind:
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HandleBlockEntrance(Loc.castAs<BlockEntrance>(), Pred);
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break;
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case ProgramPoint::BlockExitKind:
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assert (false && "BlockExit location never occur in forward analysis.");
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break;
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case ProgramPoint::CallEnterKind: {
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HandleCallEnter(Loc.castAs<CallEnter>(), Pred);
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break;
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}
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case ProgramPoint::CallExitBeginKind:
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SubEng.processCallExit(Pred);
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break;
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case ProgramPoint::EpsilonKind: {
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assert(Pred->hasSinglePred() &&
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"Assume epsilon has exactly one predecessor by construction");
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ExplodedNode *PNode = Pred->getFirstPred();
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dispatchWorkItem(Pred, PNode->getLocation(), WU);
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break;
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}
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default:
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assert(Loc.getAs<PostStmt>() ||
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Loc.getAs<PostInitializer>() ||
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Loc.getAs<PostImplicitCall>() ||
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Loc.getAs<CallExitEnd>() ||
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Loc.getAs<LoopExit>() ||
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Loc.getAs<PostAllocatorCall>());
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HandlePostStmt(WU.getBlock(), WU.getIndex(), Pred);
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break;
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}
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}
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bool CoreEngine::ExecuteWorkListWithInitialState(const LocationContext *L,
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unsigned Steps,
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ProgramStateRef InitState,
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ExplodedNodeSet &Dst) {
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bool DidNotFinish = ExecuteWorkList(L, Steps, InitState);
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for (ExplodedGraph::eop_iterator I = G.eop_begin(), E = G.eop_end(); I != E;
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++I) {
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Dst.Add(*I);
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}
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return DidNotFinish;
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}
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void CoreEngine::HandleBlockEdge(const BlockEdge &L, ExplodedNode *Pred) {
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const CFGBlock *Blk = L.getDst();
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NodeBuilderContext BuilderCtx(*this, Blk, Pred);
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// Mark this block as visited.
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const LocationContext *LC = Pred->getLocationContext();
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FunctionSummaries->markVisitedBasicBlock(Blk->getBlockID(),
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LC->getDecl(),
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LC->getCFG()->getNumBlockIDs());
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// Check if we are entering the EXIT block.
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if (Blk == &(L.getLocationContext()->getCFG()->getExit())) {
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assert (L.getLocationContext()->getCFG()->getExit().size() == 0
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&& "EXIT block cannot contain Stmts.");
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// Get return statement..
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const ReturnStmt *RS = nullptr;
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if (!L.getSrc()->empty()) {
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if (Optional<CFGStmt> LastStmt = L.getSrc()->back().getAs<CFGStmt>()) {
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RS = dyn_cast<ReturnStmt>(LastStmt->getStmt());
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}
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}
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// Process the final state transition.
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SubEng.processEndOfFunction(BuilderCtx, Pred, RS);
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// This path is done. Don't enqueue any more nodes.
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return;
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}
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// Call into the SubEngine to process entering the CFGBlock.
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ExplodedNodeSet dstNodes;
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BlockEntrance BE(Blk, Pred->getLocationContext());
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NodeBuilderWithSinks nodeBuilder(Pred, dstNodes, BuilderCtx, BE);
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SubEng.processCFGBlockEntrance(L, nodeBuilder, Pred);
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// Auto-generate a node.
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if (!nodeBuilder.hasGeneratedNodes()) {
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nodeBuilder.generateNode(Pred->State, Pred);
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}
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// Enqueue nodes onto the worklist.
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enqueue(dstNodes);
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}
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void CoreEngine::HandleBlockEntrance(const BlockEntrance &L,
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ExplodedNode *Pred) {
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// Increment the block counter.
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const LocationContext *LC = Pred->getLocationContext();
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unsigned BlockId = L.getBlock()->getBlockID();
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BlockCounter Counter = WList->getBlockCounter();
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Counter = BCounterFactory.IncrementCount(Counter, LC->getCurrentStackFrame(),
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BlockId);
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WList->setBlockCounter(Counter);
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// Process the entrance of the block.
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if (Optional<CFGElement> E = L.getFirstElement()) {
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NodeBuilderContext Ctx(*this, L.getBlock(), Pred);
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SubEng.processCFGElement(*E, Pred, 0, &Ctx);
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}
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else
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HandleBlockExit(L.getBlock(), Pred);
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}
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void CoreEngine::HandleBlockExit(const CFGBlock * B, ExplodedNode *Pred) {
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if (const Stmt *Term = B->getTerminator()) {
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switch (Term->getStmtClass()) {
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default:
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llvm_unreachable("Analysis for this terminator not implemented.");
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case Stmt::CXXBindTemporaryExprClass:
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HandleCleanupTemporaryBranch(
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cast<CXXBindTemporaryExpr>(B->getTerminator().getStmt()), B, Pred);
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return;
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// Model static initializers.
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case Stmt::DeclStmtClass:
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HandleStaticInit(cast<DeclStmt>(Term), B, Pred);
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return;
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case Stmt::BinaryOperatorClass: // '&&' and '||'
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HandleBranch(cast<BinaryOperator>(Term)->getLHS(), Term, B, Pred);
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return;
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case Stmt::BinaryConditionalOperatorClass:
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case Stmt::ConditionalOperatorClass:
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HandleBranch(cast<AbstractConditionalOperator>(Term)->getCond(),
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Term, B, Pred);
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return;
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// FIXME: Use constant-folding in CFG construction to simplify this
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// case.
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case Stmt::ChooseExprClass:
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HandleBranch(cast<ChooseExpr>(Term)->getCond(), Term, B, Pred);
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return;
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case Stmt::CXXTryStmtClass: {
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// Generate a node for each of the successors.
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// Our logic for EH analysis can certainly be improved.
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for (CFGBlock::const_succ_iterator it = B->succ_begin(),
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et = B->succ_end(); it != et; ++it) {
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if (const CFGBlock *succ = *it) {
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generateNode(BlockEdge(B, succ, Pred->getLocationContext()),
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Pred->State, Pred);
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}
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}
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return;
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}
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case Stmt::DoStmtClass:
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HandleBranch(cast<DoStmt>(Term)->getCond(), Term, B, Pred);
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return;
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case Stmt::CXXForRangeStmtClass:
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HandleBranch(cast<CXXForRangeStmt>(Term)->getCond(), Term, B, Pred);
|
|
return;
|
|
|
|
case Stmt::ForStmtClass:
|
|
HandleBranch(cast<ForStmt>(Term)->getCond(), Term, B, Pred);
|
|
return;
|
|
|
|
case Stmt::ContinueStmtClass:
|
|
case Stmt::BreakStmtClass:
|
|
case Stmt::GotoStmtClass:
|
|
break;
|
|
|
|
case Stmt::IfStmtClass:
|
|
HandleBranch(cast<IfStmt>(Term)->getCond(), Term, B, Pred);
|
|
return;
|
|
|
|
case Stmt::IndirectGotoStmtClass: {
|
|
// Only 1 successor: the indirect goto dispatch block.
|
|
assert (B->succ_size() == 1);
|
|
|
|
IndirectGotoNodeBuilder
|
|
builder(Pred, B, cast<IndirectGotoStmt>(Term)->getTarget(),
|
|
*(B->succ_begin()), this);
|
|
|
|
SubEng.processIndirectGoto(builder);
|
|
return;
|
|
}
|
|
|
|
case Stmt::ObjCForCollectionStmtClass: {
|
|
// In the case of ObjCForCollectionStmt, it appears twice in a CFG:
|
|
//
|
|
// (1) inside a basic block, which represents the binding of the
|
|
// 'element' variable to a value.
|
|
// (2) in a terminator, which represents the branch.
|
|
//
|
|
// For (1), subengines will bind a value (i.e., 0 or 1) indicating
|
|
// whether or not collection contains any more elements. We cannot
|
|
// just test to see if the element is nil because a container can
|
|
// contain nil elements.
|
|
HandleBranch(Term, Term, B, Pred);
|
|
return;
|
|
}
|
|
|
|
case Stmt::SwitchStmtClass: {
|
|
SwitchNodeBuilder builder(Pred, B, cast<SwitchStmt>(Term)->getCond(),
|
|
this);
|
|
|
|
SubEng.processSwitch(builder);
|
|
return;
|
|
}
|
|
|
|
case Stmt::WhileStmtClass:
|
|
HandleBranch(cast<WhileStmt>(Term)->getCond(), Term, B, Pred);
|
|
return;
|
|
}
|
|
}
|
|
|
|
assert (B->succ_size() == 1 &&
|
|
"Blocks with no terminator should have at most 1 successor.");
|
|
|
|
generateNode(BlockEdge(B, *(B->succ_begin()), Pred->getLocationContext()),
|
|
Pred->State, Pred);
|
|
}
|
|
|
|
void CoreEngine::HandleCallEnter(const CallEnter &CE, ExplodedNode *Pred) {
|
|
NodeBuilderContext BuilderCtx(*this, CE.getEntry(), Pred);
|
|
SubEng.processCallEnter(BuilderCtx, CE, Pred);
|
|
}
|
|
|
|
void CoreEngine::HandleBranch(const Stmt *Cond, const Stmt *Term,
|
|
const CFGBlock * B, ExplodedNode *Pred) {
|
|
assert(B->succ_size() == 2);
|
|
NodeBuilderContext Ctx(*this, B, Pred);
|
|
ExplodedNodeSet Dst;
|
|
SubEng.processBranch(Cond, Term, Ctx, Pred, Dst,
|
|
*(B->succ_begin()), *(B->succ_begin()+1));
|
|
// Enqueue the new frontier onto the worklist.
|
|
enqueue(Dst);
|
|
}
|
|
|
|
void CoreEngine::HandleCleanupTemporaryBranch(const CXXBindTemporaryExpr *BTE,
|
|
const CFGBlock *B,
|
|
ExplodedNode *Pred) {
|
|
assert(B->succ_size() == 2);
|
|
NodeBuilderContext Ctx(*this, B, Pred);
|
|
ExplodedNodeSet Dst;
|
|
SubEng.processCleanupTemporaryBranch(BTE, Ctx, Pred, Dst, *(B->succ_begin()),
|
|
*(B->succ_begin() + 1));
|
|
// Enqueue the new frontier onto the worklist.
|
|
enqueue(Dst);
|
|
}
|
|
|
|
void CoreEngine::HandleStaticInit(const DeclStmt *DS, const CFGBlock *B,
|
|
ExplodedNode *Pred) {
|
|
assert(B->succ_size() == 2);
|
|
NodeBuilderContext Ctx(*this, B, Pred);
|
|
ExplodedNodeSet Dst;
|
|
SubEng.processStaticInitializer(DS, Ctx, Pred, Dst,
|
|
*(B->succ_begin()), *(B->succ_begin()+1));
|
|
// Enqueue the new frontier onto the worklist.
|
|
enqueue(Dst);
|
|
}
|
|
|
|
|
|
void CoreEngine::HandlePostStmt(const CFGBlock *B, unsigned StmtIdx,
|
|
ExplodedNode *Pred) {
|
|
assert(B);
|
|
assert(!B->empty());
|
|
|
|
if (StmtIdx == B->size())
|
|
HandleBlockExit(B, Pred);
|
|
else {
|
|
NodeBuilderContext Ctx(*this, B, Pred);
|
|
SubEng.processCFGElement((*B)[StmtIdx], Pred, StmtIdx, &Ctx);
|
|
}
|
|
}
|
|
|
|
/// generateNode - Utility method to generate nodes, hook up successors,
|
|
/// and add nodes to the worklist.
|
|
void CoreEngine::generateNode(const ProgramPoint &Loc,
|
|
ProgramStateRef State,
|
|
ExplodedNode *Pred) {
|
|
|
|
bool IsNew;
|
|
ExplodedNode *Node = G.getNode(Loc, State, false, &IsNew);
|
|
|
|
if (Pred)
|
|
Node->addPredecessor(Pred, G); // Link 'Node' with its predecessor.
|
|
else {
|
|
assert (IsNew);
|
|
G.addRoot(Node); // 'Node' has no predecessor. Make it a root.
|
|
}
|
|
|
|
// Only add 'Node' to the worklist if it was freshly generated.
|
|
if (IsNew) WList->enqueue(Node);
|
|
}
|
|
|
|
void CoreEngine::enqueueStmtNode(ExplodedNode *N,
|
|
const CFGBlock *Block, unsigned Idx) {
|
|
assert(Block);
|
|
assert (!N->isSink());
|
|
|
|
// Check if this node entered a callee.
|
|
if (N->getLocation().getAs<CallEnter>()) {
|
|
// Still use the index of the CallExpr. It's needed to create the callee
|
|
// StackFrameContext.
|
|
WList->enqueue(N, Block, Idx);
|
|
return;
|
|
}
|
|
|
|
// Do not create extra nodes. Move to the next CFG element.
|
|
if (N->getLocation().getAs<PostInitializer>() ||
|
|
N->getLocation().getAs<PostImplicitCall>()||
|
|
N->getLocation().getAs<LoopExit>()) {
|
|
WList->enqueue(N, Block, Idx+1);
|
|
return;
|
|
}
|
|
|
|
if (N->getLocation().getAs<EpsilonPoint>()) {
|
|
WList->enqueue(N, Block, Idx);
|
|
return;
|
|
}
|
|
|
|
if ((*Block)[Idx].getKind() == CFGElement::NewAllocator) {
|
|
WList->enqueue(N, Block, Idx+1);
|
|
return;
|
|
}
|
|
|
|
// At this point, we know we're processing a normal statement.
|
|
CFGStmt CS = (*Block)[Idx].castAs<CFGStmt>();
|
|
PostStmt Loc(CS.getStmt(), N->getLocationContext());
|
|
|
|
if (Loc == N->getLocation().withTag(nullptr)) {
|
|
// Note: 'N' should be a fresh node because otherwise it shouldn't be
|
|
// a member of Deferred.
|
|
WList->enqueue(N, Block, Idx+1);
|
|
return;
|
|
}
|
|
|
|
bool IsNew;
|
|
ExplodedNode *Succ = G.getNode(Loc, N->getState(), false, &IsNew);
|
|
Succ->addPredecessor(N, G);
|
|
|
|
if (IsNew)
|
|
WList->enqueue(Succ, Block, Idx+1);
|
|
}
|
|
|
|
ExplodedNode *CoreEngine::generateCallExitBeginNode(ExplodedNode *N,
|
|
const ReturnStmt *RS) {
|
|
// Create a CallExitBegin node and enqueue it.
|
|
const StackFrameContext *LocCtx
|
|
= cast<StackFrameContext>(N->getLocationContext());
|
|
|
|
// Use the callee location context.
|
|
CallExitBegin Loc(LocCtx, RS);
|
|
|
|
bool isNew;
|
|
ExplodedNode *Node = G.getNode(Loc, N->getState(), false, &isNew);
|
|
Node->addPredecessor(N, G);
|
|
return isNew ? Node : nullptr;
|
|
}
|
|
|
|
|
|
void CoreEngine::enqueue(ExplodedNodeSet &Set) {
|
|
for (ExplodedNodeSet::iterator I = Set.begin(),
|
|
E = Set.end(); I != E; ++I) {
|
|
WList->enqueue(*I);
|
|
}
|
|
}
|
|
|
|
void CoreEngine::enqueue(ExplodedNodeSet &Set,
|
|
const CFGBlock *Block, unsigned Idx) {
|
|
for (ExplodedNodeSet::iterator I = Set.begin(),
|
|
E = Set.end(); I != E; ++I) {
|
|
enqueueStmtNode(*I, Block, Idx);
|
|
}
|
|
}
|
|
|
|
void CoreEngine::enqueueEndOfFunction(ExplodedNodeSet &Set, const ReturnStmt *RS) {
|
|
for (ExplodedNodeSet::iterator I = Set.begin(), E = Set.end(); I != E; ++I) {
|
|
ExplodedNode *N = *I;
|
|
// If we are in an inlined call, generate CallExitBegin node.
|
|
if (N->getLocationContext()->getParent()) {
|
|
N = generateCallExitBeginNode(N, RS);
|
|
if (N)
|
|
WList->enqueue(N);
|
|
} else {
|
|
// TODO: We should run remove dead bindings here.
|
|
G.addEndOfPath(N);
|
|
NumPathsExplored++;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void NodeBuilder::anchor() { }
|
|
|
|
ExplodedNode* NodeBuilder::generateNodeImpl(const ProgramPoint &Loc,
|
|
ProgramStateRef State,
|
|
ExplodedNode *FromN,
|
|
bool MarkAsSink) {
|
|
HasGeneratedNodes = true;
|
|
bool IsNew;
|
|
ExplodedNode *N = C.Eng.G.getNode(Loc, State, MarkAsSink, &IsNew);
|
|
N->addPredecessor(FromN, C.Eng.G);
|
|
Frontier.erase(FromN);
|
|
|
|
if (!IsNew)
|
|
return nullptr;
|
|
|
|
if (!MarkAsSink)
|
|
Frontier.Add(N);
|
|
|
|
return N;
|
|
}
|
|
|
|
void NodeBuilderWithSinks::anchor() { }
|
|
|
|
StmtNodeBuilder::~StmtNodeBuilder() {
|
|
if (EnclosingBldr)
|
|
for (ExplodedNodeSet::iterator I = Frontier.begin(),
|
|
E = Frontier.end(); I != E; ++I )
|
|
EnclosingBldr->addNodes(*I);
|
|
}
|
|
|
|
void BranchNodeBuilder::anchor() { }
|
|
|
|
ExplodedNode *BranchNodeBuilder::generateNode(ProgramStateRef State,
|
|
bool branch,
|
|
ExplodedNode *NodePred) {
|
|
// If the branch has been marked infeasible we should not generate a node.
|
|
if (!isFeasible(branch))
|
|
return nullptr;
|
|
|
|
ProgramPoint Loc = BlockEdge(C.Block, branch ? DstT:DstF,
|
|
NodePred->getLocationContext());
|
|
ExplodedNode *Succ = generateNodeImpl(Loc, State, NodePred);
|
|
return Succ;
|
|
}
|
|
|
|
ExplodedNode*
|
|
IndirectGotoNodeBuilder::generateNode(const iterator &I,
|
|
ProgramStateRef St,
|
|
bool IsSink) {
|
|
bool IsNew;
|
|
ExplodedNode *Succ =
|
|
Eng.G.getNode(BlockEdge(Src, I.getBlock(), Pred->getLocationContext()),
|
|
St, IsSink, &IsNew);
|
|
Succ->addPredecessor(Pred, Eng.G);
|
|
|
|
if (!IsNew)
|
|
return nullptr;
|
|
|
|
if (!IsSink)
|
|
Eng.WList->enqueue(Succ);
|
|
|
|
return Succ;
|
|
}
|
|
|
|
|
|
ExplodedNode*
|
|
SwitchNodeBuilder::generateCaseStmtNode(const iterator &I,
|
|
ProgramStateRef St) {
|
|
|
|
bool IsNew;
|
|
ExplodedNode *Succ =
|
|
Eng.G.getNode(BlockEdge(Src, I.getBlock(), Pred->getLocationContext()),
|
|
St, false, &IsNew);
|
|
Succ->addPredecessor(Pred, Eng.G);
|
|
if (!IsNew)
|
|
return nullptr;
|
|
|
|
Eng.WList->enqueue(Succ);
|
|
return Succ;
|
|
}
|
|
|
|
|
|
ExplodedNode*
|
|
SwitchNodeBuilder::generateDefaultCaseNode(ProgramStateRef St,
|
|
bool IsSink) {
|
|
// Get the block for the default case.
|
|
assert(Src->succ_rbegin() != Src->succ_rend());
|
|
CFGBlock *DefaultBlock = *Src->succ_rbegin();
|
|
|
|
// Sanity check for default blocks that are unreachable and not caught
|
|
// by earlier stages.
|
|
if (!DefaultBlock)
|
|
return nullptr;
|
|
|
|
bool IsNew;
|
|
ExplodedNode *Succ =
|
|
Eng.G.getNode(BlockEdge(Src, DefaultBlock, Pred->getLocationContext()),
|
|
St, IsSink, &IsNew);
|
|
Succ->addPredecessor(Pred, Eng.G);
|
|
|
|
if (!IsNew)
|
|
return nullptr;
|
|
|
|
if (!IsSink)
|
|
Eng.WList->enqueue(Succ);
|
|
|
|
return Succ;
|
|
}
|