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-rw-r--r--lib/Analysis/GRState.cpp318
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diff --git a/lib/Analysis/GRState.cpp b/lib/Analysis/GRState.cpp
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+//= GRState*cpp - Path-Sens. "State" for tracking valuues -----*- 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 SymbolRef, ExprBindKey, and GRState*
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/PathSensitive/GRStateTrait.h"
+#include "clang/Analysis/PathSensitive/GRState.h"
+#include "clang/Analysis/PathSensitive/GRTransferFuncs.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang;
+
+// Give the vtable for ConstraintManager somewhere to live.
+ConstraintManager::~ConstraintManager() {}
+
+GRStateManager::~GRStateManager() {
+ for (std::vector<GRState::Printer*>::iterator I=Printers.begin(),
+ E=Printers.end(); I!=E; ++I)
+ delete *I;
+
+ for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end();
+ I!=E; ++I)
+ I->second.second(I->second.first);
+}
+
+const GRState*
+GRStateManager::RemoveDeadBindings(const GRState* state, Stmt* Loc,
+ SymbolReaper& SymReaper) {
+
+ // This code essentially performs a "mark-and-sweep" of the VariableBindings.
+ // The roots are any Block-level exprs and Decls that our liveness algorithm
+ // tells us are live. We then see what Decls they may reference, and keep
+ // those around. This code more than likely can be made faster, and the
+ // frequency of which this method is called should be experimented with
+ // for optimum performance.
+ llvm::SmallVector<const MemRegion*, 10> RegionRoots;
+ GRState NewState = *state;
+
+ NewState.Env = EnvMgr.RemoveDeadBindings(NewState.Env, Loc, SymReaper, *this,
+ state, RegionRoots);
+
+ // Clean up the store.
+ NewState.St = StoreMgr->RemoveDeadBindings(&NewState, Loc, SymReaper,
+ RegionRoots);
+
+ return ConstraintMgr->RemoveDeadBindings(getPersistentState(NewState),
+ SymReaper);
+}
+
+const GRState* GRStateManager::Unbind(const GRState* St, Loc LV) {
+ Store OldStore = St->getStore();
+ Store NewStore = StoreMgr->Remove(OldStore, LV);
+
+ if (NewStore == OldStore)
+ return St;
+
+ GRState NewSt = *St;
+ NewSt.St = NewStore;
+ return getPersistentState(NewSt);
+}
+
+const GRState* GRStateManager::getInitialState() {
+
+ GRState StateImpl(EnvMgr.getInitialEnvironment(),
+ StoreMgr->getInitialStore(),
+ GDMFactory.GetEmptyMap());
+
+ return getPersistentState(StateImpl);
+}
+
+const GRState* GRStateManager::getPersistentState(GRState& State) {
+
+ llvm::FoldingSetNodeID ID;
+ State.Profile(ID);
+ void* InsertPos;
+
+ if (GRState* I = StateSet.FindNodeOrInsertPos(ID, InsertPos))
+ return I;
+
+ GRState* I = (GRState*) Alloc.Allocate<GRState>();
+ new (I) GRState(State);
+ StateSet.InsertNode(I, InsertPos);
+ return I;
+}
+
+const GRState* GRStateManager::MakeStateWithStore(const GRState* St,
+ Store store) {
+ GRState NewSt = *St;
+ NewSt.St = store;
+ return getPersistentState(NewSt);
+}
+
+
+//===----------------------------------------------------------------------===//
+// State pretty-printing.
+//===----------------------------------------------------------------------===//
+
+void GRState::print(std::ostream& Out, StoreManager& StoreMgr,
+ ConstraintManager& ConstraintMgr,
+ Printer** Beg, Printer** End,
+ const char* nl, const char* sep) const {
+
+ // Print the store.
+ StoreMgr.print(getStore(), Out, nl, sep);
+
+ // Print Subexpression bindings.
+ bool isFirst = true;
+
+ for (seb_iterator I = seb_begin(), E = seb_end(); I != E; ++I) {
+
+ if (isFirst) {
+ Out << nl << nl << "Sub-Expressions:" << nl;
+ isFirst = false;
+ }
+ else { Out << nl; }
+
+ Out << " (" << (void*) I.getKey() << ") ";
+ llvm::raw_os_ostream OutS(Out);
+ I.getKey()->printPretty(OutS);
+ OutS.flush();
+ Out << " : ";
+ I.getData().print(Out);
+ }
+
+ // Print block-expression bindings.
+ isFirst = true;
+
+ for (beb_iterator I = beb_begin(), E = beb_end(); I != E; ++I) {
+
+ if (isFirst) {
+ Out << nl << nl << "Block-level Expressions:" << nl;
+ isFirst = false;
+ }
+ else { Out << nl; }
+
+ Out << " (" << (void*) I.getKey() << ") ";
+ llvm::raw_os_ostream OutS(Out);
+ I.getKey()->printPretty(OutS);
+ OutS.flush();
+ Out << " : ";
+ I.getData().print(Out);
+ }
+
+ ConstraintMgr.print(this, Out, nl, sep);
+
+ // Print checker-specific data.
+ for ( ; Beg != End ; ++Beg) (*Beg)->Print(Out, this, nl, sep);
+}
+
+void GRStateRef::printDOT(std::ostream& Out) const {
+ print(Out, "\\l", "\\|");
+}
+
+void GRStateRef::printStdErr() const {
+ print(*llvm::cerr);
+}
+
+void GRStateRef::print(std::ostream& Out, const char* nl, const char* sep)const{
+ GRState::Printer **beg = Mgr->Printers.empty() ? 0 : &Mgr->Printers[0];
+ GRState::Printer **end = !beg ? 0 : beg + Mgr->Printers.size();
+ St->print(Out, *Mgr->StoreMgr, *Mgr->ConstraintMgr, beg, end, nl, sep);
+}
+
+//===----------------------------------------------------------------------===//
+// Generic Data Map.
+//===----------------------------------------------------------------------===//
+
+void* const* GRState::FindGDM(void* K) const {
+ return GDM.lookup(K);
+}
+
+void*
+GRStateManager::FindGDMContext(void* K,
+ void* (*CreateContext)(llvm::BumpPtrAllocator&),
+ void (*DeleteContext)(void*)) {
+
+ std::pair<void*, void (*)(void*)>& p = GDMContexts[K];
+ if (!p.first) {
+ p.first = CreateContext(Alloc);
+ p.second = DeleteContext;
+ }
+
+ return p.first;
+}
+
+const GRState* GRStateManager::addGDM(const GRState* St, void* Key, void* Data){
+ GRState::GenericDataMap M1 = St->getGDM();
+ GRState::GenericDataMap M2 = GDMFactory.Add(M1, Key, Data);
+
+ if (M1 == M2)
+ return St;
+
+ GRState NewSt = *St;
+ NewSt.GDM = M2;
+ return getPersistentState(NewSt);
+}
+
+//===----------------------------------------------------------------------===//
+// Utility.
+//===----------------------------------------------------------------------===//
+
+namespace {
+class VISIBILITY_HIDDEN ScanReachableSymbols : public SubRegionMap::Visitor {
+ typedef llvm::DenseSet<const MemRegion*> VisitedRegionsTy;
+
+ VisitedRegionsTy visited;
+ GRStateRef state;
+ SymbolVisitor &visitor;
+ llvm::OwningPtr<SubRegionMap> SRM;
+public:
+
+ ScanReachableSymbols(GRStateManager* sm, const GRState *st, SymbolVisitor& v)
+ : state(st, *sm), visitor(v) {}
+
+ bool scan(nonloc::CompoundVal val);
+ bool scan(SVal val);
+ bool scan(const MemRegion *R);
+
+ // From SubRegionMap::Visitor.
+ bool Visit(const MemRegion* Parent, const MemRegion* SubRegion) {
+ return scan(SubRegion);
+ }
+};
+}
+
+bool ScanReachableSymbols::scan(nonloc::CompoundVal val) {
+ for (nonloc::CompoundVal::iterator I=val.begin(), E=val.end(); I!=E; ++I)
+ if (!scan(*I))
+ return false;
+
+ return true;
+}
+
+bool ScanReachableSymbols::scan(SVal val) {
+ if (loc::MemRegionVal *X = dyn_cast<loc::MemRegionVal>(&val))
+ return scan(X->getRegion());
+
+ if (SymbolRef Sym = val.getAsSymbol())
+ return visitor.VisitSymbol(Sym);
+
+ if (nonloc::CompoundVal *X = dyn_cast<nonloc::CompoundVal>(&val))
+ return scan(*X);
+
+ return true;
+}
+
+bool ScanReachableSymbols::scan(const MemRegion *R) {
+ if (isa<MemSpaceRegion>(R) || visited.count(R))
+ return true;
+
+ visited.insert(R);
+
+ // If this is a symbolic region, visit the symbol for the region.
+ if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R))
+ if (!visitor.VisitSymbol(SR->getSymbol()))
+ return false;
+
+ // If this is a subregion, also visit the parent regions.
+ if (const SubRegion *SR = dyn_cast<SubRegion>(R))
+ if (!scan(SR->getSuperRegion()))
+ return false;
+
+ // Now look at the binding to this region (if any).
+ if (!scan(state.GetSValAsScalarOrLoc(R)))
+ return false;
+
+ // Now look at the subregions.
+ if (!SRM.get())
+ SRM.reset(state.getManager().getStoreManager().getSubRegionMap(state));
+
+ return SRM->iterSubRegions(R, *this);
+}
+
+bool GRStateManager::scanReachableSymbols(SVal val, const GRState* state,
+ SymbolVisitor& visitor) {
+ ScanReachableSymbols S(this, state, visitor);
+ return S.scan(val);
+}
+
+//===----------------------------------------------------------------------===//
+// Queries.
+//===----------------------------------------------------------------------===//
+
+bool GRStateManager::isEqual(const GRState* state, Expr* Ex,
+ const llvm::APSInt& Y) {
+
+ SVal V = GetSVal(state, Ex);
+
+ if (loc::ConcreteInt* X = dyn_cast<loc::ConcreteInt>(&V))
+ return X->getValue() == Y;
+
+ if (nonloc::ConcreteInt* X = dyn_cast<nonloc::ConcreteInt>(&V))
+ return X->getValue() == Y;
+
+ if (SymbolRef Sym = V.getAsSymbol())
+ return ConstraintMgr->isEqual(state, Sym, Y);
+
+ return false;
+}
+
+bool GRStateManager::isEqual(const GRState* state, Expr* Ex, uint64_t x) {
+ return isEqual(state, Ex, getBasicVals().getValue(x, Ex->getType()));
+}
+
+//===----------------------------------------------------------------------===//
+// Persistent values for indexing into the Generic Data Map.
+
+int GRState::NullDerefTag::TagInt = 0;
+
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