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diff --git a/clang/lib/Analysis/CFG.cpp b/clang/lib/Analysis/CFG.cpp
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+//===--- CFG.cpp - Classes for representing and building CFGs----*- 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 the CFG and CFGBuilder classes for representing and
+// building Control-Flow Graphs (CFGs) from ASTs.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/SaveAndRestore.h"
+#include "clang/Analysis/CFG.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/StmtVisitor.h"
+#include "clang/AST/PrettyPrinter.h"
+#include "clang/AST/CharUnits.h"
+#include "clang/Basic/AttrKinds.h"
+#include "llvm/Support/GraphWriter.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/Format.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/OwningPtr.h"
+
+using namespace clang;
+
+namespace {
+
+static SourceLocation GetEndLoc(Decl *D) {
+ if (VarDecl *VD = dyn_cast<VarDecl>(D))
+ if (Expr *Ex = VD->getInit())
+ return Ex->getSourceRange().getEnd();
+ return D->getLocation();
+}
+
+class CFGBuilder;
+
+/// The CFG builder uses a recursive algorithm to build the CFG. When
+/// we process an expression, sometimes we know that we must add the
+/// subexpressions as block-level expressions. For example:
+///
+/// exp1 || exp2
+///
+/// When processing the '||' expression, we know that exp1 and exp2
+/// need to be added as block-level expressions, even though they
+/// might not normally need to be. AddStmtChoice records this
+/// contextual information. If AddStmtChoice is 'NotAlwaysAdd', then
+/// the builder has an option not to add a subexpression as a
+/// block-level expression.
+///
+class AddStmtChoice {
+public:
+ enum Kind { NotAlwaysAdd = 0, AlwaysAdd = 1 };
+
+ AddStmtChoice(Kind a_kind = NotAlwaysAdd) : kind(a_kind) {}
+
+ bool alwaysAdd(CFGBuilder &builder,
+ const Stmt *stmt) const;
+
+ /// Return a copy of this object, except with the 'always-add' bit
+ /// set as specified.
+ AddStmtChoice withAlwaysAdd(bool alwaysAdd) const {
+ return AddStmtChoice(alwaysAdd ? AlwaysAdd : NotAlwaysAdd);
+ }
+
+private:
+ Kind kind;
+};
+
+/// LocalScope - Node in tree of local scopes created for C++ implicit
+/// destructor calls generation. It contains list of automatic variables
+/// declared in the scope and link to position in previous scope this scope
+/// began in.
+///
+/// The process of creating local scopes is as follows:
+/// - Init CFGBuilder::ScopePos with invalid position (equivalent for null),
+/// - Before processing statements in scope (e.g. CompoundStmt) create
+/// LocalScope object using CFGBuilder::ScopePos as link to previous scope
+/// and set CFGBuilder::ScopePos to the end of new scope,
+/// - On every occurrence of VarDecl increase CFGBuilder::ScopePos if it points
+/// at this VarDecl,
+/// - For every normal (without jump) end of scope add to CFGBlock destructors
+/// for objects in the current scope,
+/// - For every jump add to CFGBlock destructors for objects
+/// between CFGBuilder::ScopePos and local scope position saved for jump
+/// target. Thanks to C++ restrictions on goto jumps we can be sure that
+/// jump target position will be on the path to root from CFGBuilder::ScopePos
+/// (adding any variable that doesn't need constructor to be called to
+/// LocalScope can break this assumption),
+///
+class LocalScope {
+public:
+ typedef BumpVector<VarDecl*> AutomaticVarsTy;
+
+ /// const_iterator - Iterates local scope backwards and jumps to previous
+ /// scope on reaching the beginning of currently iterated scope.
+ class const_iterator {
+ const LocalScope* Scope;
+
+ /// VarIter is guaranteed to be greater then 0 for every valid iterator.
+ /// Invalid iterator (with null Scope) has VarIter equal to 0.
+ unsigned VarIter;
+
+ public:
+ /// Create invalid iterator. Dereferencing invalid iterator is not allowed.
+ /// Incrementing invalid iterator is allowed and will result in invalid
+ /// iterator.
+ const_iterator()
+ : Scope(NULL), VarIter(0) {}
+
+ /// Create valid iterator. In case when S.Prev is an invalid iterator and
+ /// I is equal to 0, this will create invalid iterator.
+ const_iterator(const LocalScope& S, unsigned I)
+ : Scope(&S), VarIter(I) {
+ // Iterator to "end" of scope is not allowed. Handle it by going up
+ // in scopes tree possibly up to invalid iterator in the root.
+ if (VarIter == 0 && Scope)
+ *this = Scope->Prev;
+ }
+
+ VarDecl *const* operator->() const {
+ assert (Scope && "Dereferencing invalid iterator is not allowed");
+ assert (VarIter != 0 && "Iterator has invalid value of VarIter member");
+ return &Scope->Vars[VarIter - 1];
+ }
+ VarDecl *operator*() const {
+ return *this->operator->();
+ }
+
+ const_iterator &operator++() {
+ if (!Scope)
+ return *this;
+
+ assert (VarIter != 0 && "Iterator has invalid value of VarIter member");
+ --VarIter;
+ if (VarIter == 0)
+ *this = Scope->Prev;
+ return *this;
+ }
+ const_iterator operator++(int) {
+ const_iterator P = *this;
+ ++*this;
+ return P;
+ }
+
+ bool operator==(const const_iterator &rhs) const {
+ return Scope == rhs.Scope && VarIter == rhs.VarIter;
+ }
+ bool operator!=(const const_iterator &rhs) const {
+ return !(*this == rhs);
+ }
+
+ operator bool() const {
+ return *this != const_iterator();
+ }
+
+ int distance(const_iterator L);
+ };
+
+ friend class const_iterator;
+
+private:
+ BumpVectorContext ctx;
+
+ /// Automatic variables in order of declaration.
+ AutomaticVarsTy Vars;
+ /// Iterator to variable in previous scope that was declared just before
+ /// begin of this scope.
+ const_iterator Prev;
+
+public:
+ /// Constructs empty scope linked to previous scope in specified place.
+ LocalScope(BumpVectorContext &ctx, const_iterator P)
+ : ctx(ctx), Vars(ctx, 4), Prev(P) {}
+
+ /// Begin of scope in direction of CFG building (backwards).
+ const_iterator begin() const { return const_iterator(*this, Vars.size()); }
+
+ void addVar(VarDecl *VD) {
+ Vars.push_back(VD, ctx);
+ }
+};
+
+/// distance - Calculates distance from this to L. L must be reachable from this
+/// (with use of ++ operator). Cost of calculating the distance is linear w.r.t.
+/// number of scopes between this and L.
+int LocalScope::const_iterator::distance(LocalScope::const_iterator L) {
+ int D = 0;
+ const_iterator F = *this;
+ while (F.Scope != L.Scope) {
+ assert (F != const_iterator()
+ && "L iterator is not reachable from F iterator.");
+ D += F.VarIter;
+ F = F.Scope->Prev;
+ }
+ D += F.VarIter - L.VarIter;
+ return D;
+}
+
+/// BlockScopePosPair - Structure for specifying position in CFG during its
+/// build process. It consists of CFGBlock that specifies position in CFG graph
+/// and LocalScope::const_iterator that specifies position in LocalScope graph.
+struct BlockScopePosPair {
+ BlockScopePosPair() : block(0) {}
+ BlockScopePosPair(CFGBlock *b, LocalScope::const_iterator scopePos)
+ : block(b), scopePosition(scopePos) {}
+
+ CFGBlock *block;
+ LocalScope::const_iterator scopePosition;
+};
+
+/// TryResult - a class representing a variant over the values
+/// 'true', 'false', or 'unknown'. This is returned by tryEvaluateBool,
+/// and is used by the CFGBuilder to decide if a branch condition
+/// can be decided up front during CFG construction.
+class TryResult {
+ int X;
+public:
+ TryResult(bool b) : X(b ? 1 : 0) {}
+ TryResult() : X(-1) {}
+
+ bool isTrue() const { return X == 1; }
+ bool isFalse() const { return X == 0; }
+ bool isKnown() const { return X >= 0; }
+ void negate() {
+ assert(isKnown());
+ X ^= 0x1;
+ }
+};
+
+/// CFGBuilder - This class implements CFG construction from an AST.
+/// The builder is stateful: an instance of the builder should be used to only
+/// construct a single CFG.
+///
+/// Example usage:
+///
+/// CFGBuilder builder;
+/// CFG* cfg = builder.BuildAST(stmt1);
+///
+/// CFG construction is done via a recursive walk of an AST. We actually parse
+/// the AST in reverse order so that the successor of a basic block is
+/// constructed prior to its predecessor. This allows us to nicely capture
+/// implicit fall-throughs without extra basic blocks.
+///
+class CFGBuilder {
+ typedef BlockScopePosPair JumpTarget;
+ typedef BlockScopePosPair JumpSource;
+
+ ASTContext *Context;
+ OwningPtr<CFG> cfg;
+
+ CFGBlock *Block;
+ CFGBlock *Succ;
+ JumpTarget ContinueJumpTarget;
+ JumpTarget BreakJumpTarget;
+ CFGBlock *SwitchTerminatedBlock;
+ CFGBlock *DefaultCaseBlock;
+ CFGBlock *TryTerminatedBlock;
+
+ // Current position in local scope.
+ LocalScope::const_iterator ScopePos;
+
+ // LabelMap records the mapping from Label expressions to their jump targets.
+ typedef llvm::DenseMap<LabelDecl*, JumpTarget> LabelMapTy;
+ LabelMapTy LabelMap;
+
+ // A list of blocks that end with a "goto" that must be backpatched to their
+ // resolved targets upon completion of CFG construction.
+ typedef std::vector<JumpSource> BackpatchBlocksTy;
+ BackpatchBlocksTy BackpatchBlocks;
+
+ // A list of labels whose address has been taken (for indirect gotos).
+ typedef llvm::SmallPtrSet<LabelDecl*, 5> LabelSetTy;
+ LabelSetTy AddressTakenLabels;
+
+ bool badCFG;
+ const CFG::BuildOptions &BuildOpts;
+
+ // State to track for building switch statements.
+ bool switchExclusivelyCovered;
+ Expr::EvalResult *switchCond;
+
+ CFG::BuildOptions::ForcedBlkExprs::value_type *cachedEntry;
+ const Stmt *lastLookup;
+
+ // Caches boolean evaluations of expressions to avoid multiple re-evaluations
+ // during construction of branches for chained logical operators.
+ typedef llvm::DenseMap<Expr *, TryResult> CachedBoolEvalsTy;
+ CachedBoolEvalsTy CachedBoolEvals;
+
+public:
+ explicit CFGBuilder(ASTContext *astContext,
+ const CFG::BuildOptions &buildOpts)
+ : Context(astContext), cfg(new CFG()), // crew a new CFG
+ Block(NULL), Succ(NULL),
+ SwitchTerminatedBlock(NULL), DefaultCaseBlock(NULL),
+ TryTerminatedBlock(NULL), badCFG(false), BuildOpts(buildOpts),
+ switchExclusivelyCovered(false), switchCond(0),
+ cachedEntry(0), lastLookup(0) {}
+
+ // buildCFG - Used by external clients to construct the CFG.
+ CFG* buildCFG(const Decl *D, Stmt *Statement);
+
+ bool alwaysAdd(const Stmt *stmt);
+
+private:
+ // Visitors to walk an AST and construct the CFG.
+ CFGBlock *VisitAddrLabelExpr(AddrLabelExpr *A, AddStmtChoice asc);
+ CFGBlock *VisitBinaryOperator(BinaryOperator *B, AddStmtChoice asc);
+ CFGBlock *VisitBreakStmt(BreakStmt *B);
+ CFGBlock *VisitCXXCatchStmt(CXXCatchStmt *S);
+ CFGBlock *VisitExprWithCleanups(ExprWithCleanups *E,
+ AddStmtChoice asc);
+ CFGBlock *VisitCXXThrowExpr(CXXThrowExpr *T);
+ CFGBlock *VisitCXXTryStmt(CXXTryStmt *S);
+ CFGBlock *VisitCXXForRangeStmt(CXXForRangeStmt *S);
+ CFGBlock *VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E,
+ AddStmtChoice asc);
+ CFGBlock *VisitCXXConstructExpr(CXXConstructExpr *C, AddStmtChoice asc);
+ CFGBlock *VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E,
+ AddStmtChoice asc);
+ CFGBlock *VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *C,
+ AddStmtChoice asc);
+ CFGBlock *VisitCallExpr(CallExpr *C, AddStmtChoice asc);
+ CFGBlock *VisitCaseStmt(CaseStmt *C);
+ CFGBlock *VisitChooseExpr(ChooseExpr *C, AddStmtChoice asc);
+ CFGBlock *VisitCompoundStmt(CompoundStmt *C);
+ CFGBlock *VisitConditionalOperator(AbstractConditionalOperator *C,
+ AddStmtChoice asc);
+ CFGBlock *VisitContinueStmt(ContinueStmt *C);
+ CFGBlock *VisitDeclStmt(DeclStmt *DS);
+ CFGBlock *VisitDeclSubExpr(DeclStmt *DS);
+ CFGBlock *VisitDefaultStmt(DefaultStmt *D);
+ CFGBlock *VisitDoStmt(DoStmt *D);
+ CFGBlock *VisitLambdaExpr(LambdaExpr *E, AddStmtChoice asc);
+ CFGBlock *VisitForStmt(ForStmt *F);
+ CFGBlock *VisitGotoStmt(GotoStmt *G);
+ CFGBlock *VisitIfStmt(IfStmt *I);
+ CFGBlock *VisitImplicitCastExpr(ImplicitCastExpr *E, AddStmtChoice asc);
+ CFGBlock *VisitIndirectGotoStmt(IndirectGotoStmt *I);
+ CFGBlock *VisitLabelStmt(LabelStmt *L);
+ CFGBlock *VisitLambdaExpr(LambdaExpr *L);
+ CFGBlock *VisitMemberExpr(MemberExpr *M, AddStmtChoice asc);
+ CFGBlock *VisitObjCAtCatchStmt(ObjCAtCatchStmt *S);
+ CFGBlock *VisitObjCAutoreleasePoolStmt(ObjCAutoreleasePoolStmt *S);
+ CFGBlock *VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S);
+ CFGBlock *VisitObjCAtThrowStmt(ObjCAtThrowStmt *S);
+ CFGBlock *VisitObjCAtTryStmt(ObjCAtTryStmt *S);
+ CFGBlock *VisitObjCForCollectionStmt(ObjCForCollectionStmt *S);
+ CFGBlock *VisitReturnStmt(ReturnStmt *R);
+ CFGBlock *VisitPseudoObjectExpr(PseudoObjectExpr *E);
+ CFGBlock *VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *E,
+ AddStmtChoice asc);
+ CFGBlock *VisitStmtExpr(StmtExpr *S, AddStmtChoice asc);
+ CFGBlock *VisitSwitchStmt(SwitchStmt *S);
+ CFGBlock *VisitUnaryOperator(UnaryOperator *U, AddStmtChoice asc);
+ CFGBlock *VisitWhileStmt(WhileStmt *W);
+
+ CFGBlock *Visit(Stmt *S, AddStmtChoice asc = AddStmtChoice::NotAlwaysAdd);
+ CFGBlock *VisitStmt(Stmt *S, AddStmtChoice asc);
+ CFGBlock *VisitChildren(Stmt *S);
+ CFGBlock *VisitNoRecurse(Expr *E, AddStmtChoice asc);
+
+ // Visitors to walk an AST and generate destructors of temporaries in
+ // full expression.
+ CFGBlock *VisitForTemporaryDtors(Stmt *E, bool BindToTemporary = false);
+ CFGBlock *VisitChildrenForTemporaryDtors(Stmt *E);
+ CFGBlock *VisitBinaryOperatorForTemporaryDtors(BinaryOperator *E);
+ CFGBlock *VisitCXXBindTemporaryExprForTemporaryDtors(CXXBindTemporaryExpr *E,
+ bool BindToTemporary);
+ CFGBlock *
+ VisitConditionalOperatorForTemporaryDtors(AbstractConditionalOperator *E,
+ bool BindToTemporary);
+
+ // NYS == Not Yet Supported
+ CFGBlock *NYS() {
+ badCFG = true;
+ return Block;
+ }
+
+ void autoCreateBlock() { if (!Block) Block = createBlock(); }
+ CFGBlock *createBlock(bool add_successor = true);
+ CFGBlock *createNoReturnBlock();
+
+ CFGBlock *addStmt(Stmt *S) {
+ return Visit(S, AddStmtChoice::AlwaysAdd);
+ }
+ CFGBlock *addInitializer(CXXCtorInitializer *I);
+ void addAutomaticObjDtors(LocalScope::const_iterator B,
+ LocalScope::const_iterator E, Stmt *S);
+ void addImplicitDtorsForDestructor(const CXXDestructorDecl *DD);
+
+ // Local scopes creation.
+ LocalScope* createOrReuseLocalScope(LocalScope* Scope);
+
+ void addLocalScopeForStmt(Stmt *S);
+ LocalScope* addLocalScopeForDeclStmt(DeclStmt *DS, LocalScope* Scope = NULL);
+ LocalScope* addLocalScopeForVarDecl(VarDecl *VD, LocalScope* Scope = NULL);
+
+ void addLocalScopeAndDtors(Stmt *S);
+
+ // Interface to CFGBlock - adding CFGElements.
+ void appendStmt(CFGBlock *B, const Stmt *S) {
+ if (alwaysAdd(S) && cachedEntry)
+ cachedEntry->second = B;
+
+ // All block-level expressions should have already been IgnoreParens()ed.
+ assert(!isa<Expr>(S) || cast<Expr>(S)->IgnoreParens() == S);
+ B->appendStmt(const_cast<Stmt*>(S), cfg->getBumpVectorContext());
+ }
+ void appendInitializer(CFGBlock *B, CXXCtorInitializer *I) {
+ B->appendInitializer(I, cfg->getBumpVectorContext());
+ }
+ void appendBaseDtor(CFGBlock *B, const CXXBaseSpecifier *BS) {
+ B->appendBaseDtor(BS, cfg->getBumpVectorContext());
+ }
+ void appendMemberDtor(CFGBlock *B, FieldDecl *FD) {
+ B->appendMemberDtor(FD, cfg->getBumpVectorContext());
+ }
+ void appendTemporaryDtor(CFGBlock *B, CXXBindTemporaryExpr *E) {
+ B->appendTemporaryDtor(E, cfg->getBumpVectorContext());
+ }
+ void appendAutomaticObjDtor(CFGBlock *B, VarDecl *VD, Stmt *S) {
+ B->appendAutomaticObjDtor(VD, S, cfg->getBumpVectorContext());
+ }
+
+ void prependAutomaticObjDtorsWithTerminator(CFGBlock *Blk,
+ LocalScope::const_iterator B, LocalScope::const_iterator E);
+
+ void addSuccessor(CFGBlock *B, CFGBlock *S) {
+ B->addSuccessor(S, cfg->getBumpVectorContext());
+ }
+
+ /// Try and evaluate an expression to an integer constant.
+ bool tryEvaluate(Expr *S, Expr::EvalResult &outResult) {
+ if (!BuildOpts.PruneTriviallyFalseEdges)
+ return false;
+ return !S->isTypeDependent() &&
+ !S->isValueDependent() &&
+ S->EvaluateAsRValue(outResult, *Context);
+ }
+
+ /// tryEvaluateBool - Try and evaluate the Stmt and return 0 or 1
+ /// if we can evaluate to a known value, otherwise return -1.
+ TryResult tryEvaluateBool(Expr *S) {
+ if (!BuildOpts.PruneTriviallyFalseEdges ||
+ S->isTypeDependent() || S->isValueDependent())
+ return TryResult();
+
+ if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(S)) {
+ if (Bop->isLogicalOp()) {
+ // Check the cache first.
+ CachedBoolEvalsTy::iterator I = CachedBoolEvals.find(S);
+ if (I != CachedBoolEvals.end())
+ return I->second; // already in map;
+
+ // Retrieve result at first, or the map might be updated.
+ TryResult Result = evaluateAsBooleanConditionNoCache(S);
+ CachedBoolEvals[S] = Result; // update or insert
+ return Result;
+ }
+ }
+
+ return evaluateAsBooleanConditionNoCache(S);
+ }
+
+ /// \brief Evaluate as boolean \param E without using the cache.
+ TryResult evaluateAsBooleanConditionNoCache(Expr *E) {
+ if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(E)) {
+ if (Bop->isLogicalOp()) {
+ TryResult LHS = tryEvaluateBool(Bop->getLHS());
+ if (LHS.isKnown()) {
+ // We were able to evaluate the LHS, see if we can get away with not
+ // evaluating the RHS: 0 && X -> 0, 1 || X -> 1
+ if (LHS.isTrue() == (Bop->getOpcode() == BO_LOr))
+ return LHS.isTrue();
+
+ TryResult RHS = tryEvaluateBool(Bop->getRHS());
+ if (RHS.isKnown()) {
+ if (Bop->getOpcode() == BO_LOr)
+ return LHS.isTrue() || RHS.isTrue();
+ else
+ return LHS.isTrue() && RHS.isTrue();
+ }
+ } else {
+ TryResult RHS = tryEvaluateBool(Bop->getRHS());
+ if (RHS.isKnown()) {
+ // We can't evaluate the LHS; however, sometimes the result
+ // is determined by the RHS: X && 0 -> 0, X || 1 -> 1.
+ if (RHS.isTrue() == (Bop->getOpcode() == BO_LOr))
+ return RHS.isTrue();
+ }
+ }
+
+ return TryResult();
+ }
+ }
+
+ bool Result;
+ if (E->EvaluateAsBooleanCondition(Result, *Context))
+ return Result;
+
+ return TryResult();
+ }
+
+};
+
+inline bool AddStmtChoice::alwaysAdd(CFGBuilder &builder,
+ const Stmt *stmt) const {
+ return builder.alwaysAdd(stmt) || kind == AlwaysAdd;
+}
+
+bool CFGBuilder::alwaysAdd(const Stmt *stmt) {
+ bool shouldAdd = BuildOpts.alwaysAdd(stmt);
+
+ if (!BuildOpts.forcedBlkExprs)
+ return shouldAdd;
+
+ if (lastLookup == stmt) {
+ if (cachedEntry) {
+ assert(cachedEntry->first == stmt);
+ return true;
+ }
+ return shouldAdd;
+ }
+
+ lastLookup = stmt;
+
+ // Perform the lookup!
+ CFG::BuildOptions::ForcedBlkExprs *fb = *BuildOpts.forcedBlkExprs;
+
+ if (!fb) {
+ // No need to update 'cachedEntry', since it will always be null.
+ assert(cachedEntry == 0);
+ return shouldAdd;
+ }
+
+ CFG::BuildOptions::ForcedBlkExprs::iterator itr = fb->find(stmt);
+ if (itr == fb->end()) {
+ cachedEntry = 0;
+ return shouldAdd;
+ }
+
+ cachedEntry = &*itr;
+ return true;
+}
+
+// FIXME: Add support for dependent-sized array types in C++?
+// Does it even make sense to build a CFG for an uninstantiated template?
+static const VariableArrayType *FindVA(const Type *t) {
+ while (const ArrayType *vt = dyn_cast<ArrayType>(t)) {
+ if (const VariableArrayType *vat = dyn_cast<VariableArrayType>(vt))
+ if (vat->getSizeExpr())
+ return vat;
+
+ t = vt->getElementType().getTypePtr();
+ }
+
+ return 0;
+}
+
+/// BuildCFG - Constructs a CFG from an AST (a Stmt*). The AST can represent an
+/// arbitrary statement. Examples include a single expression or a function
+/// body (compound statement). The ownership of the returned CFG is
+/// transferred to the caller. If CFG construction fails, this method returns
+/// NULL.
+CFG* CFGBuilder::buildCFG(const Decl *D, Stmt *Statement) {
+ assert(cfg.get());
+ if (!Statement)
+ return NULL;
+
+ // Create an empty block that will serve as the exit block for the CFG. Since
+ // this is the first block added to the CFG, it will be implicitly registered
+ // as the exit block.
+ Succ = createBlock();
+ assert(Succ == &cfg->getExit());
+ Block = NULL; // the EXIT block is empty. Create all other blocks lazily.
+
+ if (BuildOpts.AddImplicitDtors)
+ if (const CXXDestructorDecl *DD = dyn_cast_or_null<CXXDestructorDecl>(D))
+ addImplicitDtorsForDestructor(DD);
+
+ // Visit the statements and create the CFG.
+ CFGBlock *B = addStmt(Statement);
+
+ if (badCFG)
+ return NULL;
+
+ // For C++ constructor add initializers to CFG.
+ if (const CXXConstructorDecl *CD = dyn_cast_or_null<CXXConstructorDecl>(D)) {
+ for (CXXConstructorDecl::init_const_reverse_iterator I = CD->init_rbegin(),
+ E = CD->init_rend(); I != E; ++I) {
+ B = addInitializer(*I);
+ if (badCFG)
+ return NULL;
+ }
+ }
+
+ if (B)
+ Succ = B;
+
+ // Backpatch the gotos whose label -> block mappings we didn't know when we
+ // encountered them.
+ for (BackpatchBlocksTy::iterator I = BackpatchBlocks.begin(),
+ E = BackpatchBlocks.end(); I != E; ++I ) {
+
+ CFGBlock *B = I->block;
+ GotoStmt *G = cast<GotoStmt>(B->getTerminator());
+ LabelMapTy::iterator LI = LabelMap.find(G->getLabel());
+
+ // If there is no target for the goto, then we are looking at an
+ // incomplete AST. Handle this by not registering a successor.
+ if (LI == LabelMap.end()) continue;
+
+ JumpTarget JT = LI->second;
+ prependAutomaticObjDtorsWithTerminator(B, I->scopePosition,
+ JT.scopePosition);
+ addSuccessor(B, JT.block);
+ }
+
+ // Add successors to the Indirect Goto Dispatch block (if we have one).
+ if (CFGBlock *B = cfg->getIndirectGotoBlock())
+ for (LabelSetTy::iterator I = AddressTakenLabels.begin(),
+ E = AddressTakenLabels.end(); I != E; ++I ) {
+
+ // Lookup the target block.
+ LabelMapTy::iterator LI = LabelMap.find(*I);
+
+ // If there is no target block that contains label, then we are looking
+ // at an incomplete AST. Handle this by not registering a successor.
+ if (LI == LabelMap.end()) continue;
+
+ addSuccessor(B, LI->second.block);
+ }
+
+ // Create an empty entry block that has no predecessors.
+ cfg->setEntry(createBlock());
+
+ return cfg.take();
+}
+
+/// createBlock - Used to lazily create blocks that are connected
+/// to the current (global) succcessor.
+CFGBlock *CFGBuilder::createBlock(bool add_successor) {
+ CFGBlock *B = cfg->createBlock();
+ if (add_successor && Succ)
+ addSuccessor(B, Succ);
+ return B;
+}
+
+/// createNoReturnBlock - Used to create a block is a 'noreturn' point in the
+/// CFG. It is *not* connected to the current (global) successor, and instead
+/// directly tied to the exit block in order to be reachable.
+CFGBlock *CFGBuilder::createNoReturnBlock() {
+ CFGBlock *B = createBlock(false);
+ B->setHasNoReturnElement();
+ addSuccessor(B, &cfg->getExit());
+ return B;
+}
+
+/// addInitializer - Add C++ base or member initializer element to CFG.
+CFGBlock *CFGBuilder::addInitializer(CXXCtorInitializer *I) {
+ if (!BuildOpts.AddInitializers)
+ return Block;
+
+ bool IsReference = false;
+ bool HasTemporaries = false;
+
+ // Destructors of temporaries in initialization expression should be called
+ // after initialization finishes.
+ Expr *Init = I->getInit();
+ if (Init) {
+ if (FieldDecl *FD = I->getAnyMember())
+ IsReference = FD->getType()->isReferenceType();
+ HasTemporaries = isa<ExprWithCleanups>(Init);
+
+ if (BuildOpts.AddImplicitDtors && HasTemporaries) {
+ // Generate destructors for temporaries in initialization expression.
+ VisitForTemporaryDtors(cast<ExprWithCleanups>(Init)->getSubExpr(),
+ IsReference);
+ }
+ }
+
+ autoCreateBlock();
+ appendInitializer(Block, I);
+
+ if (Init) {
+ if (HasTemporaries) {
+ // For expression with temporaries go directly to subexpression to omit
+ // generating destructors for the second time.
+ return Visit(cast<ExprWithCleanups>(Init)->getSubExpr());
+ }
+ return Visit(Init);
+ }
+
+ return Block;
+}
+
+/// \brief Retrieve the type of the temporary object whose lifetime was
+/// extended by a local reference with the given initializer.
+static QualType getReferenceInitTemporaryType(ASTContext &Context,
+ const Expr *Init) {
+ while (true) {
+ // Skip parentheses.
+ Init = Init->IgnoreParens();
+
+ // Skip through cleanups.
+ if (const ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(Init)) {
+ Init = EWC->getSubExpr();
+ continue;
+ }
+
+ // Skip through the temporary-materialization expression.
+ if (const MaterializeTemporaryExpr *MTE
+ = dyn_cast<MaterializeTemporaryExpr>(Init)) {
+ Init = MTE->GetTemporaryExpr();
+ continue;
+ }
+
+ // Skip derived-to-base and no-op casts.
+ if (const CastExpr *CE = dyn_cast<CastExpr>(Init)) {
+ if ((CE->getCastKind() == CK_DerivedToBase ||
+ CE->getCastKind() == CK_UncheckedDerivedToBase ||
+ CE->getCastKind() == CK_NoOp) &&
+ Init->getType()->isRecordType()) {
+ Init = CE->getSubExpr();
+ continue;
+ }
+ }
+
+ // Skip member accesses into rvalues.
+ if (const MemberExpr *ME = dyn_cast<MemberExpr>(Init)) {
+ if (!ME->isArrow() && ME->getBase()->isRValue()) {
+ Init = ME->getBase();
+ continue;
+ }
+ }
+
+ break;
+ }
+
+ return Init->getType();
+}
+
+/// addAutomaticObjDtors - Add to current block automatic objects destructors
+/// for objects in range of local scope positions. Use S as trigger statement
+/// for destructors.
+void CFGBuilder::addAutomaticObjDtors(LocalScope::const_iterator B,
+ LocalScope::const_iterator E, Stmt *S) {
+ if (!BuildOpts.AddImplicitDtors)
+ return;
+
+ if (B == E)
+ return;
+
+ // We need to append the destructors in reverse order, but any one of them
+ // may be a no-return destructor which changes the CFG. As a result, buffer
+ // this sequence up and replay them in reverse order when appending onto the
+ // CFGBlock(s).
+ SmallVector<VarDecl*, 10> Decls;
+ Decls.reserve(B.distance(E));
+ for (LocalScope::const_iterator I = B; I != E; ++I)
+ Decls.push_back(*I);
+
+ for (SmallVectorImpl<VarDecl*>::reverse_iterator I = Decls.rbegin(),
+ E = Decls.rend();
+ I != E; ++I) {
+ // If this destructor is marked as a no-return destructor, we need to
+ // create a new block for the destructor which does not have as a successor
+ // anything built thus far: control won't flow out of this block.
+ QualType Ty;
+ if ((*I)->getType()->isReferenceType()) {
+ Ty = getReferenceInitTemporaryType(*Context, (*I)->getInit());
+ } else {
+ Ty = Context->getBaseElementType((*I)->getType());
+ }
+
+ const CXXDestructorDecl *Dtor = Ty->getAsCXXRecordDecl()->getDestructor();
+ if (cast<FunctionType>(Dtor->getType())->getNoReturnAttr())
+ Block = createNoReturnBlock();
+ else
+ autoCreateBlock();
+
+ appendAutomaticObjDtor(Block, *I, S);
+ }
+}
+
+/// addImplicitDtorsForDestructor - Add implicit destructors generated for
+/// base and member objects in destructor.
+void CFGBuilder::addImplicitDtorsForDestructor(const CXXDestructorDecl *DD) {
+ assert (BuildOpts.AddImplicitDtors
+ && "Can be called only when dtors should be added");
+ const CXXRecordDecl *RD = DD->getParent();
+
+ // At the end destroy virtual base objects.
+ for (CXXRecordDecl::base_class_const_iterator VI = RD->vbases_begin(),
+ VE = RD->vbases_end(); VI != VE; ++VI) {
+ const CXXRecordDecl *CD = VI->getType()->getAsCXXRecordDecl();
+ if (!CD->hasTrivialDestructor()) {
+ autoCreateBlock();
+ appendBaseDtor(Block, VI);
+ }
+ }
+
+ // Before virtual bases destroy direct base objects.
+ for (CXXRecordDecl::base_class_const_iterator BI = RD->bases_begin(),
+ BE = RD->bases_end(); BI != BE; ++BI) {
+ if (!BI->isVirtual()) {
+ const CXXRecordDecl *CD = BI->getType()->getAsCXXRecordDecl();
+ if (!CD->hasTrivialDestructor()) {
+ autoCreateBlock();
+ appendBaseDtor(Block, BI);
+ }
+ }
+ }
+
+ // First destroy member objects.
+ for (CXXRecordDecl::field_iterator FI = RD->field_begin(),
+ FE = RD->field_end(); FI != FE; ++FI) {
+ // Check for constant size array. Set type to array element type.
+ QualType QT = FI->getType();
+ if (const ConstantArrayType *AT = Context->getAsConstantArrayType(QT)) {
+ if (AT->getSize() == 0)
+ continue;
+ QT = AT->getElementType();
+ }
+
+ if (const CXXRecordDecl *CD = QT->getAsCXXRecordDecl())
+ if (!CD->hasTrivialDestructor()) {
+ autoCreateBlock();
+ appendMemberDtor(Block, *FI);
+ }
+ }
+}
+
+/// createOrReuseLocalScope - If Scope is NULL create new LocalScope. Either
+/// way return valid LocalScope object.
+LocalScope* CFGBuilder::createOrReuseLocalScope(LocalScope* Scope) {
+ if (!Scope) {
+ llvm::BumpPtrAllocator &alloc = cfg->getAllocator();
+ Scope = alloc.Allocate<LocalScope>();
+ BumpVectorContext ctx(alloc);
+ new (Scope) LocalScope(ctx, ScopePos);
+ }
+ return Scope;
+}
+
+/// addLocalScopeForStmt - Add LocalScope to local scopes tree for statement
+/// that should create implicit scope (e.g. if/else substatements).
+void CFGBuilder::addLocalScopeForStmt(Stmt *S) {
+ if (!BuildOpts.AddImplicitDtors)
+ return;
+
+ LocalScope *Scope = 0;
+
+ // For compound statement we will be creating explicit scope.
+ if (CompoundStmt *CS = dyn_cast<CompoundStmt>(S)) {
+ for (CompoundStmt::body_iterator BI = CS->body_begin(), BE = CS->body_end()
+ ; BI != BE; ++BI) {
+ Stmt *SI = (*BI)->stripLabelLikeStatements();
+ if (DeclStmt *DS = dyn_cast<DeclStmt>(SI))
+ Scope = addLocalScopeForDeclStmt(DS, Scope);
+ }
+ return;
+ }
+
+ // For any other statement scope will be implicit and as such will be
+ // interesting only for DeclStmt.
+ if (DeclStmt *DS = dyn_cast<DeclStmt>(S->stripLabelLikeStatements()))
+ addLocalScopeForDeclStmt(DS);
+}
+
+/// addLocalScopeForDeclStmt - Add LocalScope for declaration statement. Will
+/// reuse Scope if not NULL.
+LocalScope* CFGBuilder::addLocalScopeForDeclStmt(DeclStmt *DS,
+ LocalScope* Scope) {
+ if (!BuildOpts.AddImplicitDtors)
+ return Scope;
+
+ for (DeclStmt::decl_iterator DI = DS->decl_begin(), DE = DS->decl_end()
+ ; DI != DE; ++DI) {
+ if (VarDecl *VD = dyn_cast<VarDecl>(*DI))
+ Scope = addLocalScopeForVarDecl(VD, Scope);
+ }
+ return Scope;
+}
+
+/// addLocalScopeForVarDecl - Add LocalScope for variable declaration. It will
+/// create add scope for automatic objects and temporary objects bound to
+/// const reference. Will reuse Scope if not NULL.
+LocalScope* CFGBuilder::addLocalScopeForVarDecl(VarDecl *VD,
+ LocalScope* Scope) {
+ if (!BuildOpts.AddImplicitDtors)
+ return Scope;
+
+ // Check if variable is local.
+ switch (VD->getStorageClass()) {
+ case SC_None:
+ case SC_Auto:
+ case SC_Register:
+ break;
+ default: return Scope;
+ }
+
+ // Check for const references bound to temporary. Set type to pointee.
+ QualType QT = VD->getType();
+ if (QT.getTypePtr()->isReferenceType()) {
+ if (!VD->extendsLifetimeOfTemporary())
+ return Scope;
+
+ QT = getReferenceInitTemporaryType(*Context, VD->getInit());
+ }
+
+ // Check for constant size array. Set type to array element type.
+ while (const ConstantArrayType *AT = Context->getAsConstantArrayType(QT)) {
+ if (AT->getSize() == 0)
+ return Scope;
+ QT = AT->getElementType();
+ }
+
+ // Check if type is a C++ class with non-trivial destructor.
+ if (const CXXRecordDecl *CD = QT->getAsCXXRecordDecl())
+ if (!CD->hasTrivialDestructor()) {
+ // Add the variable to scope
+ Scope = createOrReuseLocalScope(Scope);
+ Scope->addVar(VD);
+ ScopePos = Scope->begin();
+ }
+ return Scope;
+}
+
+/// addLocalScopeAndDtors - For given statement add local scope for it and
+/// add destructors that will cleanup the scope. Will reuse Scope if not NULL.
+void CFGBuilder::addLocalScopeAndDtors(Stmt *S) {
+ if (!BuildOpts.AddImplicitDtors)
+ return;
+
+ LocalScope::const_iterator scopeBeginPos = ScopePos;
+ addLocalScopeForStmt(S);
+ addAutomaticObjDtors(ScopePos, scopeBeginPos, S);
+}
+
+/// prependAutomaticObjDtorsWithTerminator - Prepend destructor CFGElements for
+/// variables with automatic storage duration to CFGBlock's elements vector.
+/// Elements will be prepended to physical beginning of the vector which
+/// happens to be logical end. Use blocks terminator as statement that specifies
+/// destructors call site.
+/// FIXME: This mechanism for adding automatic destructors doesn't handle
+/// no-return destructors properly.
+void CFGBuilder::prependAutomaticObjDtorsWithTerminator(CFGBlock *Blk,
+ LocalScope::const_iterator B, LocalScope::const_iterator E) {
+ BumpVectorContext &C = cfg->getBumpVectorContext();
+ CFGBlock::iterator InsertPos
+ = Blk->beginAutomaticObjDtorsInsert(Blk->end(), B.distance(E), C);
+ for (LocalScope::const_iterator I = B; I != E; ++I)
+ InsertPos = Blk->insertAutomaticObjDtor(InsertPos, *I,
+ Blk->getTerminator());
+}
+
+/// Visit - Walk the subtree of a statement and add extra
+/// blocks for ternary operators, &&, and ||. We also process "," and
+/// DeclStmts (which may contain nested control-flow).
+CFGBlock *CFGBuilder::Visit(Stmt * S, AddStmtChoice asc) {
+ if (!S) {
+ badCFG = true;
+ return 0;
+ }
+
+ if (Expr *E = dyn_cast<Expr>(S))
+ S = E->IgnoreParens();
+
+ switch (S->getStmtClass()) {
+ default:
+ return VisitStmt(S, asc);
+
+ case Stmt::AddrLabelExprClass:
+ return VisitAddrLabelExpr(cast<AddrLabelExpr>(S), asc);
+
+ case Stmt::BinaryConditionalOperatorClass:
+ return VisitConditionalOperator(cast<BinaryConditionalOperator>(S), asc);
+
+ case Stmt::BinaryOperatorClass:
+ return VisitBinaryOperator(cast<BinaryOperator>(S), asc);
+
+ case Stmt::BlockExprClass:
+ return VisitNoRecurse(cast<Expr>(S), asc);
+
+ case Stmt::BreakStmtClass:
+ return VisitBreakStmt(cast<BreakStmt>(S));
+
+ case Stmt::CallExprClass:
+ case Stmt::CXXOperatorCallExprClass:
+ case Stmt::CXXMemberCallExprClass:
+ case Stmt::UserDefinedLiteralClass:
+ return VisitCallExpr(cast<CallExpr>(S), asc);
+
+ case Stmt::CaseStmtClass:
+ return VisitCaseStmt(cast<CaseStmt>(S));
+
+ case Stmt::ChooseExprClass:
+ return VisitChooseExpr(cast<ChooseExpr>(S), asc);
+
+ case Stmt::CompoundStmtClass:
+ return VisitCompoundStmt(cast<CompoundStmt>(S));
+
+ case Stmt::ConditionalOperatorClass:
+ return VisitConditionalOperator(cast<ConditionalOperator>(S), asc);
+
+ case Stmt::ContinueStmtClass:
+ return VisitContinueStmt(cast<ContinueStmt>(S));
+
+ case Stmt::CXXCatchStmtClass:
+ return VisitCXXCatchStmt(cast<CXXCatchStmt>(S));
+
+ case Stmt::ExprWithCleanupsClass:
+ return VisitExprWithCleanups(cast<ExprWithCleanups>(S), asc);
+
+ case Stmt::CXXBindTemporaryExprClass:
+ return VisitCXXBindTemporaryExpr(cast<CXXBindTemporaryExpr>(S), asc);
+
+ case Stmt::CXXConstructExprClass:
+ return VisitCXXConstructExpr(cast<CXXConstructExpr>(S), asc);
+
+ case Stmt::CXXFunctionalCastExprClass:
+ return VisitCXXFunctionalCastExpr(cast<CXXFunctionalCastExpr>(S), asc);
+
+ case Stmt::CXXTemporaryObjectExprClass:
+ return VisitCXXTemporaryObjectExpr(cast<CXXTemporaryObjectExpr>(S), asc);
+
+ case Stmt::CXXThrowExprClass:
+ return VisitCXXThrowExpr(cast<CXXThrowExpr>(S));
+
+ case Stmt::CXXTryStmtClass:
+ return VisitCXXTryStmt(cast<CXXTryStmt>(S));
+
+ case Stmt::CXXForRangeStmtClass:
+ return VisitCXXForRangeStmt(cast<CXXForRangeStmt>(S));
+
+ case Stmt::DeclStmtClass:
+ return VisitDeclStmt(cast<DeclStmt>(S));
+
+ case Stmt::DefaultStmtClass:
+ return VisitDefaultStmt(cast<DefaultStmt>(S));
+
+ case Stmt::DoStmtClass:
+ return VisitDoStmt(cast<DoStmt>(S));
+
+ case Stmt::ForStmtClass:
+ return VisitForStmt(cast<ForStmt>(S));
+
+ case Stmt::GotoStmtClass:
+ return VisitGotoStmt(cast<GotoStmt>(S));
+
+ case Stmt::IfStmtClass:
+ return VisitIfStmt(cast<IfStmt>(S));
+
+ case Stmt::ImplicitCastExprClass:
+ return VisitImplicitCastExpr(cast<ImplicitCastExpr>(S), asc);
+
+ case Stmt::IndirectGotoStmtClass:
+ return VisitIndirectGotoStmt(cast<IndirectGotoStmt>(S));
+
+ case Stmt::LabelStmtClass:
+ return VisitLabelStmt(cast<LabelStmt>(S));
+
+ case Stmt::LambdaExprClass:
+ return VisitLambdaExpr(cast<LambdaExpr>(S), asc);
+
+ case Stmt::AttributedStmtClass:
+ return Visit(cast<AttributedStmt>(S)->getSubStmt(), asc);
+
+ case Stmt::MemberExprClass:
+ return VisitMemberExpr(cast<MemberExpr>(S), asc);
+
+ case Stmt::NullStmtClass:
+ return Block;
+
+ case Stmt::ObjCAtCatchStmtClass:
+ return VisitObjCAtCatchStmt(cast<ObjCAtCatchStmt>(S));
+
+ case Stmt::ObjCAutoreleasePoolStmtClass:
+ return VisitObjCAutoreleasePoolStmt(cast<ObjCAutoreleasePoolStmt>(S));
+
+ case Stmt::ObjCAtSynchronizedStmtClass:
+ return VisitObjCAtSynchronizedStmt(cast<ObjCAtSynchronizedStmt>(S));
+
+ case Stmt::ObjCAtThrowStmtClass:
+ return VisitObjCAtThrowStmt(cast<ObjCAtThrowStmt>(S));
+
+ case Stmt::ObjCAtTryStmtClass:
+ return VisitObjCAtTryStmt(cast<ObjCAtTryStmt>(S));
+
+ case Stmt::ObjCForCollectionStmtClass:
+ return VisitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(S));
+
+ case Stmt::OpaqueValueExprClass:
+ return Block;
+
+ case Stmt::PseudoObjectExprClass:
+ return VisitPseudoObjectExpr(cast<PseudoObjectExpr>(S));
+
+ case Stmt::ReturnStmtClass:
+ return VisitReturnStmt(cast<ReturnStmt>(S));
+
+ case Stmt::UnaryExprOrTypeTraitExprClass:
+ return VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S),
+ asc);
+
+ case Stmt::StmtExprClass:
+ return VisitStmtExpr(cast<StmtExpr>(S), asc);
+
+ case Stmt::SwitchStmtClass:
+ return VisitSwitchStmt(cast<SwitchStmt>(S));
+
+ case Stmt::UnaryOperatorClass:
+ return VisitUnaryOperator(cast<UnaryOperator>(S), asc);
+
+ case Stmt::WhileStmtClass:
+ return VisitWhileStmt(cast<WhileStmt>(S));
+ }
+}
+
+CFGBlock *CFGBuilder::VisitStmt(Stmt *S, AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, S)) {
+ autoCreateBlock();
+ appendStmt(Block, S);
+ }
+
+ return VisitChildren(S);
+}
+
+/// VisitChildren - Visit the children of a Stmt.
+CFGBlock *CFGBuilder::VisitChildren(Stmt *Terminator) {
+ CFGBlock *lastBlock = Block;
+ for (Stmt::child_range I = Terminator->children(); I; ++I)
+ if (Stmt *child = *I)
+ if (CFGBlock *b = Visit(child))
+ lastBlock = b;
+
+ return lastBlock;
+}
+
+CFGBlock *CFGBuilder::VisitAddrLabelExpr(AddrLabelExpr *A,
+ AddStmtChoice asc) {
+ AddressTakenLabels.insert(A->getLabel());
+
+ if (asc.alwaysAdd(*this, A)) {
+ autoCreateBlock();
+ appendStmt(Block, A);
+ }
+
+ return Block;
+}
+
+CFGBlock *CFGBuilder::VisitUnaryOperator(UnaryOperator *U,
+ AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, U)) {
+ autoCreateBlock();
+ appendStmt(Block, U);
+ }
+
+ return Visit(U->getSubExpr(), AddStmtChoice());
+}
+
+CFGBlock *CFGBuilder::VisitBinaryOperator(BinaryOperator *B,
+ AddStmtChoice asc) {
+ if (B->isLogicalOp()) { // && or ||
+ CFGBlock *ConfluenceBlock = Block ? Block : createBlock();
+ appendStmt(ConfluenceBlock, B);
+
+ if (badCFG)
+ return 0;
+
+ // create the block evaluating the LHS
+ CFGBlock *LHSBlock = createBlock(false);
+ LHSBlock->setTerminator(B);
+
+ // create the block evaluating the RHS
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ CFGBlock *RHSBlock = addStmt(B->getRHS());
+
+ if (RHSBlock) {
+ if (badCFG)
+ return 0;
+ } else {
+ // Create an empty block for cases where the RHS doesn't require
+ // any explicit statements in the CFG.
+ RHSBlock = createBlock();
+ }
+
+ // Generate the blocks for evaluating the LHS.
+ Block = LHSBlock;
+ CFGBlock *EntryLHSBlock = addStmt(B->getLHS());
+
+ // See if this is a known constant.
+ TryResult KnownVal = tryEvaluateBool(B->getLHS());
+ if (KnownVal.isKnown() && (B->getOpcode() == BO_LOr))
+ KnownVal.negate();
+
+ // Now link the LHSBlock with RHSBlock.
+ if (B->getOpcode() == BO_LOr) {
+ addSuccessor(LHSBlock, KnownVal.isTrue() ? NULL : ConfluenceBlock);
+ addSuccessor(LHSBlock, KnownVal.isFalse() ? NULL : RHSBlock);
+ } else {
+ assert(B->getOpcode() == BO_LAnd);
+ addSuccessor(LHSBlock, KnownVal.isFalse() ? NULL : RHSBlock);
+ addSuccessor(LHSBlock, KnownVal.isTrue() ? NULL : ConfluenceBlock);
+ }
+
+ return EntryLHSBlock;
+ }
+
+ if (B->getOpcode() == BO_Comma) { // ,
+ autoCreateBlock();
+ appendStmt(Block, B);
+ addStmt(B->getRHS());
+ return addStmt(B->getLHS());
+ }
+
+ if (B->isAssignmentOp()) {
+ if (asc.alwaysAdd(*this, B)) {
+ autoCreateBlock();
+ appendStmt(Block, B);
+ }
+ Visit(B->getLHS());
+ return Visit(B->getRHS());
+ }
+
+ if (asc.alwaysAdd(*this, B)) {
+ autoCreateBlock();
+ appendStmt(Block, B);
+ }
+
+ CFGBlock *RBlock = Visit(B->getRHS());
+ CFGBlock *LBlock = Visit(B->getLHS());
+ // If visiting RHS causes us to finish 'Block', e.g. the RHS is a StmtExpr
+ // containing a DoStmt, and the LHS doesn't create a new block, then we should
+ // return RBlock. Otherwise we'll incorrectly return NULL.
+ return (LBlock ? LBlock : RBlock);
+}
+
+CFGBlock *CFGBuilder::VisitNoRecurse(Expr *E, AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, E)) {
+ autoCreateBlock();
+ appendStmt(Block, E);
+ }
+ return Block;
+}
+
+CFGBlock *CFGBuilder::VisitBreakStmt(BreakStmt *B) {
+ // "break" is a control-flow statement. Thus we stop processing the current
+ // block.
+ if (badCFG)
+ return 0;
+
+ // Now create a new block that ends with the break statement.
+ Block = createBlock(false);
+ Block->setTerminator(B);
+
+ // If there is no target for the break, then we are looking at an incomplete
+ // AST. This means that the CFG cannot be constructed.
+ if (BreakJumpTarget.block) {
+ addAutomaticObjDtors(ScopePos, BreakJumpTarget.scopePosition, B);
+ addSuccessor(Block, BreakJumpTarget.block);
+ } else
+ badCFG = true;
+
+
+ return Block;
+}
+
+static bool CanThrow(Expr *E, ASTContext &Ctx) {
+ QualType Ty = E->getType();
+ if (Ty->isFunctionPointerType())
+ Ty = Ty->getAs<PointerType>()->getPointeeType();
+ else if (Ty->isBlockPointerType())
+ Ty = Ty->getAs<BlockPointerType>()->getPointeeType();
+
+ const FunctionType *FT = Ty->getAs<FunctionType>();
+ if (FT) {
+ if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT))
+ if (Proto->getExceptionSpecType() != EST_Uninstantiated &&
+ Proto->isNothrow(Ctx))
+ return false;
+ }
+ return true;
+}
+
+CFGBlock *CFGBuilder::VisitCallExpr(CallExpr *C, AddStmtChoice asc) {
+ // Compute the callee type.
+ QualType calleeType = C->getCallee()->getType();
+ if (calleeType == Context->BoundMemberTy) {
+ QualType boundType = Expr::findBoundMemberType(C->getCallee());
+
+ // We should only get a null bound type if processing a dependent
+ // CFG. Recover by assuming nothing.
+ if (!boundType.isNull()) calleeType = boundType;
+ }
+
+ // If this is a call to a no-return function, this stops the block here.
+ bool NoReturn = getFunctionExtInfo(*calleeType).getNoReturn();
+
+ bool AddEHEdge = false;
+
+ // Languages without exceptions are assumed to not throw.
+ if (Context->getLangOpts().Exceptions) {
+ if (BuildOpts.AddEHEdges)
+ AddEHEdge = true;
+ }
+
+ if (FunctionDecl *FD = C->getDirectCallee()) {
+ if (FD->hasAttr<NoReturnAttr>())
+ NoReturn = true;
+ if (FD->hasAttr<NoThrowAttr>())
+ AddEHEdge = false;
+ }
+
+ if (!CanThrow(C->getCallee(), *Context))
+ AddEHEdge = false;
+
+ if (!NoReturn && !AddEHEdge)
+ return VisitStmt(C, asc.withAlwaysAdd(true));
+
+ if (Block) {
+ Succ = Block;
+ if (badCFG)
+ return 0;
+ }
+
+ if (NoReturn)
+ Block = createNoReturnBlock();
+ else
+ Block = createBlock();
+
+ appendStmt(Block, C);
+
+ if (AddEHEdge) {
+ // Add exceptional edges.
+ if (TryTerminatedBlock)
+ addSuccessor(Block, TryTerminatedBlock);
+ else
+ addSuccessor(Block, &cfg->getExit());
+ }
+
+ return VisitChildren(C);
+}
+
+CFGBlock *CFGBuilder::VisitChooseExpr(ChooseExpr *C,
+ AddStmtChoice asc) {
+ CFGBlock *ConfluenceBlock = Block ? Block : createBlock();
+ appendStmt(ConfluenceBlock, C);
+ if (badCFG)
+ return 0;
+
+ AddStmtChoice alwaysAdd = asc.withAlwaysAdd(true);
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ CFGBlock *LHSBlock = Visit(C->getLHS(), alwaysAdd);
+ if (badCFG)
+ return 0;
+
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ CFGBlock *RHSBlock = Visit(C->getRHS(), alwaysAdd);
+ if (badCFG)
+ return 0;
+
+ Block = createBlock(false);
+ // See if this is a known constant.
+ const TryResult& KnownVal = tryEvaluateBool(C->getCond());
+ addSuccessor(Block, KnownVal.isFalse() ? NULL : LHSBlock);
+ addSuccessor(Block, KnownVal.isTrue() ? NULL : RHSBlock);
+ Block->setTerminator(C);
+ return addStmt(C->getCond());
+}
+
+
+CFGBlock *CFGBuilder::VisitCompoundStmt(CompoundStmt *C) {
+ addLocalScopeAndDtors(C);
+ CFGBlock *LastBlock = Block;
+
+ for (CompoundStmt::reverse_body_iterator I=C->body_rbegin(), E=C->body_rend();
+ I != E; ++I ) {
+ // If we hit a segment of code just containing ';' (NullStmts), we can
+ // get a null block back. In such cases, just use the LastBlock
+ if (CFGBlock *newBlock = addStmt(*I))
+ LastBlock = newBlock;
+
+ if (badCFG)
+ return NULL;
+ }
+
+ return LastBlock;
+}
+
+CFGBlock *CFGBuilder::VisitConditionalOperator(AbstractConditionalOperator *C,
+ AddStmtChoice asc) {
+ const BinaryConditionalOperator *BCO = dyn_cast<BinaryConditionalOperator>(C);
+ const OpaqueValueExpr *opaqueValue = (BCO ? BCO->getOpaqueValue() : NULL);
+
+ // Create the confluence block that will "merge" the results of the ternary
+ // expression.
+ CFGBlock *ConfluenceBlock = Block ? Block : createBlock();
+ appendStmt(ConfluenceBlock, C);
+ if (badCFG)
+ return 0;
+
+ AddStmtChoice alwaysAdd = asc.withAlwaysAdd(true);
+
+ // Create a block for the LHS expression if there is an LHS expression. A
+ // GCC extension allows LHS to be NULL, causing the condition to be the
+ // value that is returned instead.
+ // e.g: x ?: y is shorthand for: x ? x : y;
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ CFGBlock *LHSBlock = 0;
+ const Expr *trueExpr = C->getTrueExpr();
+ if (trueExpr != opaqueValue) {
+ LHSBlock = Visit(C->getTrueExpr(), alwaysAdd);
+ if (badCFG)
+ return 0;
+ Block = NULL;
+ }
+ else
+ LHSBlock = ConfluenceBlock;
+
+ // Create the block for the RHS expression.
+ Succ = ConfluenceBlock;
+ CFGBlock *RHSBlock = Visit(C->getFalseExpr(), alwaysAdd);
+ if (badCFG)
+ return 0;
+
+ // Create the block that will contain the condition.
+ Block = createBlock(false);
+
+ // See if this is a known constant.
+ const TryResult& KnownVal = tryEvaluateBool(C->getCond());
+ addSuccessor(Block, KnownVal.isFalse() ? NULL : LHSBlock);
+ addSuccessor(Block, KnownVal.isTrue() ? NULL : RHSBlock);
+ Block->setTerminator(C);
+ Expr *condExpr = C->getCond();
+
+ if (opaqueValue) {
+ // Run the condition expression if it's not trivially expressed in
+ // terms of the opaque value (or if there is no opaque value).
+ if (condExpr != opaqueValue)
+ addStmt(condExpr);
+
+ // Before that, run the common subexpression if there was one.
+ // At least one of this or the above will be run.
+ return addStmt(BCO->getCommon());
+ }
+
+ return addStmt(condExpr);
+}
+
+CFGBlock *CFGBuilder::VisitDeclStmt(DeclStmt *DS) {
+ // Check if the Decl is for an __label__. If so, elide it from the
+ // CFG entirely.
+ if (isa<LabelDecl>(*DS->decl_begin()))
+ return Block;
+
+ // This case also handles static_asserts.
+ if (DS->isSingleDecl())
+ return VisitDeclSubExpr(DS);
+
+ CFGBlock *B = 0;
+
+ // FIXME: Add a reverse iterator for DeclStmt to avoid this extra copy.
+ typedef SmallVector<Decl*,10> BufTy;
+ BufTy Buf(DS->decl_begin(), DS->decl_end());
+
+ for (BufTy::reverse_iterator I = Buf.rbegin(), E = Buf.rend(); I != E; ++I) {
+ // Get the alignment of the new DeclStmt, padding out to >=8 bytes.
+ unsigned A = llvm::AlignOf<DeclStmt>::Alignment < 8
+ ? 8 : llvm::AlignOf<DeclStmt>::Alignment;
+
+ // Allocate the DeclStmt using the BumpPtrAllocator. It will get
+ // automatically freed with the CFG.
+ DeclGroupRef DG(*I);
+ Decl *D = *I;
+ void *Mem = cfg->getAllocator().Allocate(sizeof(DeclStmt), A);
+ DeclStmt *DSNew = new (Mem) DeclStmt(DG, D->getLocation(), GetEndLoc(D));
+
+ // Append the fake DeclStmt to block.
+ B = VisitDeclSubExpr(DSNew);
+ }
+
+ return B;
+}
+
+/// VisitDeclSubExpr - Utility method to add block-level expressions for
+/// DeclStmts and initializers in them.
+CFGBlock *CFGBuilder::VisitDeclSubExpr(DeclStmt *DS) {
+ assert(DS->isSingleDecl() && "Can handle single declarations only.");
+ Decl *D = DS->getSingleDecl();
+
+ if (isa<StaticAssertDecl>(D)) {
+ // static_asserts aren't added to the CFG because they do not impact
+ // runtime semantics.
+ return Block;
+ }
+
+ VarDecl *VD = dyn_cast<VarDecl>(DS->getSingleDecl());
+
+ if (!VD) {
+ autoCreateBlock();
+ appendStmt(Block, DS);
+ return Block;
+ }
+
+ bool IsReference = false;
+ bool HasTemporaries = false;
+
+ // Destructors of temporaries in initialization expression should be called
+ // after initialization finishes.
+ Expr *Init = VD->getInit();
+ if (Init) {
+ IsReference = VD->getType()->isReferenceType();
+ HasTemporaries = isa<ExprWithCleanups>(Init);
+
+ if (BuildOpts.AddImplicitDtors && HasTemporaries) {
+ // Generate destructors for temporaries in initialization expression.
+ VisitForTemporaryDtors(cast<ExprWithCleanups>(Init)->getSubExpr(),
+ IsReference);
+ }
+ }
+
+ autoCreateBlock();
+ appendStmt(Block, DS);
+
+ // Keep track of the last non-null block, as 'Block' can be nulled out
+ // if the initializer expression is something like a 'while' in a
+ // statement-expression.
+ CFGBlock *LastBlock = Block;
+
+ if (Init) {
+ if (HasTemporaries) {
+ // For expression with temporaries go directly to subexpression to omit
+ // generating destructors for the second time.
+ ExprWithCleanups *EC = cast<ExprWithCleanups>(Init);
+ if (CFGBlock *newBlock = Visit(EC->getSubExpr()))
+ LastBlock = newBlock;
+ }
+ else {
+ if (CFGBlock *newBlock = Visit(Init))
+ LastBlock = newBlock;
+ }
+ }
+
+ // If the type of VD is a VLA, then we must process its size expressions.
+ for (const VariableArrayType* VA = FindVA(VD->getType().getTypePtr());
+ VA != 0; VA = FindVA(VA->getElementType().getTypePtr()))
+ Block = addStmt(VA->getSizeExpr());
+
+ // Remove variable from local scope.
+ if (ScopePos && VD == *ScopePos)
+ ++ScopePos;
+
+ return Block ? Block : LastBlock;
+}
+
+CFGBlock *CFGBuilder::VisitIfStmt(IfStmt *I) {
+ // We may see an if statement in the middle of a basic block, or it may be the
+ // first statement we are processing. In either case, we create a new basic
+ // block. First, we create the blocks for the then...else statements, and
+ // then we create the block containing the if statement. If we were in the
+ // middle of a block, we stop processing that block. That block is then the
+ // implicit successor for the "then" and "else" clauses.
+
+ // Save local scope position because in case of condition variable ScopePos
+ // won't be restored when traversing AST.
+ SaveAndRestore<LocalScope::const_iterator> save_scope_pos(ScopePos);
+
+ // Create local scope for possible condition variable.
+ // Store scope position. Add implicit destructor.
+ if (VarDecl *VD = I->getConditionVariable()) {
+ LocalScope::const_iterator BeginScopePos = ScopePos;
+ addLocalScopeForVarDecl(VD);
+ addAutomaticObjDtors(ScopePos, BeginScopePos, I);
+ }
+
+ // The block we were processing is now finished. Make it the successor
+ // block.
+ if (Block) {
+ Succ = Block;
+ if (badCFG)
+ return 0;
+ }
+
+ // Process the false branch.
+ CFGBlock *ElseBlock = Succ;
+
+ if (Stmt *Else = I->getElse()) {
+ SaveAndRestore<CFGBlock*> sv(Succ);
+
+ // NULL out Block so that the recursive call to Visit will
+ // create a new basic block.
+ Block = NULL;
+
+ // If branch is not a compound statement create implicit scope
+ // and add destructors.
+ if (!isa<CompoundStmt>(Else))
+ addLocalScopeAndDtors(Else);
+
+ ElseBlock = addStmt(Else);
+
+ if (!ElseBlock) // Can occur when the Else body has all NullStmts.
+ ElseBlock = sv.get();
+ else if (Block) {
+ if (badCFG)
+ return 0;
+ }
+ }
+
+ // Process the true branch.
+ CFGBlock *ThenBlock;
+ {
+ Stmt *Then = I->getThen();
+ assert(Then);
+ SaveAndRestore<CFGBlock*> sv(Succ);
+ Block = NULL;
+
+ // If branch is not a compound statement create implicit scope
+ // and add destructors.
+ if (!isa<CompoundStmt>(Then))
+ addLocalScopeAndDtors(Then);
+
+ ThenBlock = addStmt(Then);
+
+ if (!ThenBlock) {
+ // We can reach here if the "then" body has all NullStmts.
+ // Create an empty block so we can distinguish between true and false
+ // branches in path-sensitive analyses.
+ ThenBlock = createBlock(false);
+ addSuccessor(ThenBlock, sv.get());
+ } else if (Block) {
+ if (badCFG)
+ return 0;
+ }
+ }
+
+ // Now create a new block containing the if statement.
+ Block = createBlock(false);
+
+ // Set the terminator of the new block to the If statement.
+ Block->setTerminator(I);
+
+ // See if this is a known constant.
+ const TryResult &KnownVal = tryEvaluateBool(I->getCond());
+
+ // Now add the successors.
+ addSuccessor(Block, KnownVal.isFalse() ? NULL : ThenBlock);
+ addSuccessor(Block, KnownVal.isTrue()? NULL : ElseBlock);
+
+ // Add the condition as the last statement in the new block. This may create
+ // new blocks as the condition may contain control-flow. Any newly created
+ // blocks will be pointed to be "Block".
+ Block = addStmt(I->getCond());
+
+ // Finally, if the IfStmt contains a condition variable, add both the IfStmt
+ // and the condition variable initialization to the CFG.
+ if (VarDecl *VD = I->getConditionVariable()) {
+ if (Expr *Init = VD->getInit()) {
+ autoCreateBlock();
+ appendStmt(Block, I->getConditionVariableDeclStmt());
+ addStmt(Init);
+ }
+ }
+
+ return Block;
+}
+
+
+CFGBlock *CFGBuilder::VisitReturnStmt(ReturnStmt *R) {
+ // If we were in the middle of a block we stop processing that block.
+ //
+ // NOTE: If a "return" appears in the middle of a block, this means that the
+ // code afterwards is DEAD (unreachable). We still keep a basic block
+ // for that code; a simple "mark-and-sweep" from the entry block will be
+ // able to report such dead blocks.
+
+ // Create the new block.
+ Block = createBlock(false);
+
+ // The Exit block is the only successor.
+ addAutomaticObjDtors(ScopePos, LocalScope::const_iterator(), R);
+ addSuccessor(Block, &cfg->getExit());
+
+ // Add the return statement to the block. This may create new blocks if R
+ // contains control-flow (short-circuit operations).
+ return VisitStmt(R, AddStmtChoice::AlwaysAdd);
+}
+
+CFGBlock *CFGBuilder::VisitLabelStmt(LabelStmt *L) {
+ // Get the block of the labeled statement. Add it to our map.
+ addStmt(L->getSubStmt());
+ CFGBlock *LabelBlock = Block;
+
+ if (!LabelBlock) // This can happen when the body is empty, i.e.
+ LabelBlock = createBlock(); // scopes that only contains NullStmts.
+
+ assert(LabelMap.find(L->getDecl()) == LabelMap.end() &&
+ "label already in map");
+ LabelMap[L->getDecl()] = JumpTarget(LabelBlock, ScopePos);
+
+ // Labels partition blocks, so this is the end of the basic block we were
+ // processing (L is the block's label). Because this is label (and we have
+ // already processed the substatement) there is no extra control-flow to worry
+ // about.
+ LabelBlock->setLabel(L);
+ if (badCFG)
+ return 0;
+
+ // We set Block to NULL to allow lazy creation of a new block (if necessary);
+ Block = NULL;
+
+ // This block is now the implicit successor of other blocks.
+ Succ = LabelBlock;
+
+ return LabelBlock;
+}
+
+CFGBlock *CFGBuilder::VisitLambdaExpr(LambdaExpr *E, AddStmtChoice asc) {
+ CFGBlock *LastBlock = VisitNoRecurse(E, asc);
+ for (LambdaExpr::capture_init_iterator it = E->capture_init_begin(),
+ et = E->capture_init_end(); it != et; ++it) {
+ if (Expr *Init = *it) {
+ CFGBlock *Tmp = Visit(Init);
+ if (Tmp != 0)
+ LastBlock = Tmp;
+ }
+ }
+ return LastBlock;
+}
+
+CFGBlock *CFGBuilder::VisitGotoStmt(GotoStmt *G) {
+ // Goto is a control-flow statement. Thus we stop processing the current
+ // block and create a new one.
+
+ Block = createBlock(false);
+ Block->setTerminator(G);
+
+ // If we already know the mapping to the label block add the successor now.
+ LabelMapTy::iterator I = LabelMap.find(G->getLabel());
+
+ if (I == LabelMap.end())
+ // We will need to backpatch this block later.
+ BackpatchBlocks.push_back(JumpSource(Block, ScopePos));
+ else {
+ JumpTarget JT = I->second;
+ addAutomaticObjDtors(ScopePos, JT.scopePosition, G);
+ addSuccessor(Block, JT.block);
+ }
+
+ return Block;
+}
+
+CFGBlock *CFGBuilder::VisitForStmt(ForStmt *F) {
+ CFGBlock *LoopSuccessor = NULL;
+
+ // Save local scope position because in case of condition variable ScopePos
+ // won't be restored when traversing AST.
+ SaveAndRestore<LocalScope::const_iterator> save_scope_pos(ScopePos);
+
+ // Create local scope for init statement and possible condition variable.
+ // Add destructor for init statement and condition variable.
+ // Store scope position for continue statement.
+ if (Stmt *Init = F->getInit())
+ addLocalScopeForStmt(Init);
+ LocalScope::const_iterator LoopBeginScopePos = ScopePos;
+
+ if (VarDecl *VD = F->getConditionVariable())
+ addLocalScopeForVarDecl(VD);
+ LocalScope::const_iterator ContinueScopePos = ScopePos;
+
+ addAutomaticObjDtors(ScopePos, save_scope_pos.get(), F);
+
+ // "for" is a control-flow statement. Thus we stop processing the current
+ // block.
+ if (Block) {
+ if (badCFG)
+ return 0;
+ LoopSuccessor = Block;
+ } else
+ LoopSuccessor = Succ;
+
+ // Save the current value for the break targets.
+ // All breaks should go to the code following the loop.
+ SaveAndRestore<JumpTarget> save_break(BreakJumpTarget);
+ BreakJumpTarget = JumpTarget(LoopSuccessor, ScopePos);
+
+ // Because of short-circuit evaluation, the condition of the loop can span
+ // multiple basic blocks. Thus we need the "Entry" and "Exit" blocks that
+ // evaluate the condition.
+ CFGBlock *ExitConditionBlock = createBlock(false);
+ CFGBlock *EntryConditionBlock = ExitConditionBlock;
+
+ // Set the terminator for the "exit" condition block.
+ ExitConditionBlock->setTerminator(F);
+
+ // Now add the actual condition to the condition block. Because the condition
+ // itself may contain control-flow, new blocks may be created.
+ if (Stmt *C = F->getCond()) {
+ Block = ExitConditionBlock;
+ EntryConditionBlock = addStmt(C);
+ if (badCFG)
+ return 0;
+ assert(Block == EntryConditionBlock ||
+ (Block == 0 && EntryConditionBlock == Succ));
+
+ // If this block contains a condition variable, add both the condition
+ // variable and initializer to the CFG.
+ if (VarDecl *VD = F->getConditionVariable()) {
+ if (Expr *Init = VD->getInit()) {
+ autoCreateBlock();
+ appendStmt(Block, F->getConditionVariableDeclStmt());
+ EntryConditionBlock = addStmt(Init);
+ assert(Block == EntryConditionBlock);
+ }
+ }
+
+ if (Block) {
+ if (badCFG)
+ return 0;
+ }
+ }
+
+ // The condition block is the implicit successor for the loop body as well as
+ // any code above the loop.
+ Succ = EntryConditionBlock;
+
+ // See if this is a known constant.
+ TryResult KnownVal(true);
+
+ if (F->getCond())
+ KnownVal = tryEvaluateBool(F->getCond());
+
+ // Now create the loop body.
+ {
+ assert(F->getBody());
+
+ // Save the current values for Block, Succ, and continue targets.
+ SaveAndRestore<CFGBlock*> save_Block(Block), save_Succ(Succ);
+ SaveAndRestore<JumpTarget> save_continue(ContinueJumpTarget);
+
+ // Create a new block to contain the (bottom) of the loop body.
+ Block = NULL;
+
+ // Loop body should end with destructor of Condition variable (if any).
+ addAutomaticObjDtors(ScopePos, LoopBeginScopePos, F);
+
+ if (Stmt *I = F->getInc()) {
+ // Generate increment code in its own basic block. This is the target of
+ // continue statements.
+ Succ = addStmt(I);
+ } else {
+ // No increment code. Create a special, empty, block that is used as the
+ // target block for "looping back" to the start of the loop.
+ assert(Succ == EntryConditionBlock);
+ Succ = Block ? Block : createBlock();
+ }
+
+ // Finish up the increment (or empty) block if it hasn't been already.
+ if (Block) {
+ assert(Block == Succ);
+ if (badCFG)
+ return 0;
+ Block = 0;
+ }
+
+ ContinueJumpTarget = JumpTarget(Succ, ContinueScopePos);
+
+ // The starting block for the loop increment is the block that should
+ // represent the 'loop target' for looping back to the start of the loop.
+ ContinueJumpTarget.block->setLoopTarget(F);
+
+ // If body is not a compound statement create implicit scope
+ // and add destructors.
+ if (!isa<CompoundStmt>(F->getBody()))
+ addLocalScopeAndDtors(F->getBody());
+
+ // Now populate the body block, and in the process create new blocks as we
+ // walk the body of the loop.
+ CFGBlock *BodyBlock = addStmt(F->getBody());
+
+ if (!BodyBlock)
+ BodyBlock = ContinueJumpTarget.block;//can happen for "for (...;...;...);"
+ else if (badCFG)
+ return 0;
+
+ // This new body block is a successor to our "exit" condition block.
+ addSuccessor(ExitConditionBlock, KnownVal.isFalse() ? NULL : BodyBlock);
+ }
+
+ // Link up the condition block with the code that follows the loop. (the
+ // false branch).
+ addSuccessor(ExitConditionBlock, KnownVal.isTrue() ? NULL : LoopSuccessor);
+
+ // If the loop contains initialization, create a new block for those
+ // statements. This block can also contain statements that precede the loop.
+ if (Stmt *I = F->getInit()) {
+ Block = createBlock();
+ return addStmt(I);
+ }
+
+ // There is no loop initialization. We are thus basically a while loop.
+ // NULL out Block to force lazy block construction.
+ Block = NULL;
+ Succ = EntryConditionBlock;
+ return EntryConditionBlock;
+}
+
+CFGBlock *CFGBuilder::VisitMemberExpr(MemberExpr *M, AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, M)) {
+ autoCreateBlock();
+ appendStmt(Block, M);
+ }
+ return Visit(M->getBase());
+}
+
+CFGBlock *CFGBuilder::VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
+ // Objective-C fast enumeration 'for' statements:
+ // http://developer.apple.com/documentation/Cocoa/Conceptual/ObjectiveC
+ //
+ // for ( Type newVariable in collection_expression ) { statements }
+ //
+ // becomes:
+ //
+ // prologue:
+ // 1. collection_expression
+ // T. jump to loop_entry
+ // loop_entry:
+ // 1. side-effects of element expression
+ // 1. ObjCForCollectionStmt [performs binding to newVariable]
+ // T. ObjCForCollectionStmt TB, FB [jumps to TB if newVariable != nil]
+ // TB:
+ // statements
+ // T. jump to loop_entry
+ // FB:
+ // what comes after
+ //
+ // and
+ //
+ // Type existingItem;
+ // for ( existingItem in expression ) { statements }
+ //
+ // becomes:
+ //
+ // the same with newVariable replaced with existingItem; the binding works
+ // the same except that for one ObjCForCollectionStmt::getElement() returns
+ // a DeclStmt and the other returns a DeclRefExpr.
+ //
+
+ CFGBlock *LoopSuccessor = 0;
+
+ if (Block) {
+ if (badCFG)
+ return 0;
+ LoopSuccessor = Block;
+ Block = 0;
+ } else
+ LoopSuccessor = Succ;
+
+ // Build the condition blocks.
+ CFGBlock *ExitConditionBlock = createBlock(false);
+
+ // Set the terminator for the "exit" condition block.
+ ExitConditionBlock->setTerminator(S);
+
+ // The last statement in the block should be the ObjCForCollectionStmt, which
+ // performs the actual binding to 'element' and determines if there are any
+ // more items in the collection.
+ appendStmt(ExitConditionBlock, S);
+ Block = ExitConditionBlock;
+
+ // Walk the 'element' expression to see if there are any side-effects. We
+ // generate new blocks as necessary. We DON'T add the statement by default to
+ // the CFG unless it contains control-flow.
+ CFGBlock *EntryConditionBlock = Visit(S->getElement(),
+ AddStmtChoice::NotAlwaysAdd);
+ if (Block) {
+ if (badCFG)
+ return 0;
+ Block = 0;
+ }
+
+ // The condition block is the implicit successor for the loop body as well as
+ // any code above the loop.
+ Succ = EntryConditionBlock;
+
+ // Now create the true branch.
+ {
+ // Save the current values for Succ, continue and break targets.
+ SaveAndRestore<CFGBlock*> save_Succ(Succ);
+ SaveAndRestore<JumpTarget> save_continue(ContinueJumpTarget),
+ save_break(BreakJumpTarget);
+
+ BreakJumpTarget = JumpTarget(LoopSuccessor, ScopePos);
+ ContinueJumpTarget = JumpTarget(EntryConditionBlock, ScopePos);
+
+ CFGBlock *BodyBlock = addStmt(S->getBody());
+
+ if (!BodyBlock)
+ BodyBlock = EntryConditionBlock; // can happen for "for (X in Y) ;"
+ else if (Block) {
+ if (badCFG)
+ return 0;
+ }
+
+ // This new body block is a successor to our "exit" condition block.
+ addSuccessor(ExitConditionBlock, BodyBlock);
+ }
+
+ // Link up the condition block with the code that follows the loop.
+ // (the false branch).
+ addSuccessor(ExitConditionBlock, LoopSuccessor);
+
+ // Now create a prologue block to contain the collection expression.
+ Block = createBlock();
+ return addStmt(S->getCollection());
+}
+
+CFGBlock *CFGBuilder::VisitObjCAutoreleasePoolStmt(ObjCAutoreleasePoolStmt *S) {
+ // Inline the body.
+ return addStmt(S->getSubStmt());
+ // TODO: consider adding cleanups for the end of @autoreleasepool scope.
+}
+
+CFGBlock *CFGBuilder::VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
+ // FIXME: Add locking 'primitives' to CFG for @synchronized.
+
+ // Inline the body.
+ CFGBlock *SyncBlock = addStmt(S->getSynchBody());
+
+ // The sync body starts its own basic block. This makes it a little easier
+ // for diagnostic clients.
+ if (SyncBlock) {
+ if (badCFG)
+ return 0;
+
+ Block = 0;
+ Succ = SyncBlock;
+ }
+
+ // Add the @synchronized to the CFG.
+ autoCreateBlock();
+ appendStmt(Block, S);
+
+ // Inline the sync expression.
+ return addStmt(S->getSynchExpr());
+}
+
+CFGBlock *CFGBuilder::VisitObjCAtTryStmt(ObjCAtTryStmt *S) {
+ // FIXME
+ return NYS();
+}
+
+CFGBlock *CFGBuilder::VisitPseudoObjectExpr(PseudoObjectExpr *E) {
+ autoCreateBlock();
+
+ // Add the PseudoObject as the last thing.
+ appendStmt(Block, E);
+
+ CFGBlock *lastBlock = Block;
+
+ // Before that, evaluate all of the semantics in order. In
+ // CFG-land, that means appending them in reverse order.
+ for (unsigned i = E->getNumSemanticExprs(); i != 0; ) {
+ Expr *Semantic = E->getSemanticExpr(--i);
+
+ // If the semantic is an opaque value, we're being asked to bind
+ // it to its source expression.
+ if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(Semantic))
+ Semantic = OVE->getSourceExpr();
+
+ if (CFGBlock *B = Visit(Semantic))
+ lastBlock = B;
+ }
+
+ return lastBlock;
+}
+
+CFGBlock *CFGBuilder::VisitWhileStmt(WhileStmt *W) {
+ CFGBlock *LoopSuccessor = NULL;
+
+ // Save local scope position because in case of condition variable ScopePos
+ // won't be restored when traversing AST.
+ SaveAndRestore<LocalScope::const_iterator> save_scope_pos(ScopePos);
+
+ // Create local scope for possible condition variable.
+ // Store scope position for continue statement.
+ LocalScope::const_iterator LoopBeginScopePos = ScopePos;
+ if (VarDecl *VD = W->getConditionVariable()) {
+ addLocalScopeForVarDecl(VD);
+ addAutomaticObjDtors(ScopePos, LoopBeginScopePos, W);
+ }
+
+ // "while" is a control-flow statement. Thus we stop processing the current
+ // block.
+ if (Block) {
+ if (badCFG)
+ return 0;
+ LoopSuccessor = Block;
+ Block = 0;
+ } else
+ LoopSuccessor = Succ;
+
+ // Because of short-circuit evaluation, the condition of the loop can span
+ // multiple basic blocks. Thus we need the "Entry" and "Exit" blocks that
+ // evaluate the condition.
+ CFGBlock *ExitConditionBlock = createBlock(false);
+ CFGBlock *EntryConditionBlock = ExitConditionBlock;
+
+ // Set the terminator for the "exit" condition block.
+ ExitConditionBlock->setTerminator(W);
+
+ // Now add the actual condition to the condition block. Because the condition
+ // itself may contain control-flow, new blocks may be created. Thus we update
+ // "Succ" after adding the condition.
+ if (Stmt *C = W->getCond()) {
+ Block = ExitConditionBlock;
+ EntryConditionBlock = addStmt(C);
+ // The condition might finish the current 'Block'.
+ Block = EntryConditionBlock;
+
+ // If this block contains a condition variable, add both the condition
+ // variable and initializer to the CFG.
+ if (VarDecl *VD = W->getConditionVariable()) {
+ if (Expr *Init = VD->getInit()) {
+ autoCreateBlock();
+ appendStmt(Block, W->getConditionVariableDeclStmt());
+ EntryConditionBlock = addStmt(Init);
+ assert(Block == EntryConditionBlock);
+ }
+ }
+
+ if (Block) {
+ if (badCFG)
+ return 0;
+ }
+ }
+
+ // The condition block is the implicit successor for the loop body as well as
+ // any code above the loop.
+ Succ = EntryConditionBlock;
+
+ // See if this is a known constant.
+ const TryResult& KnownVal = tryEvaluateBool(W->getCond());
+
+ // Process the loop body.
+ {
+ assert(W->getBody());
+
+ // Save the current values for Block, Succ, and continue and break targets
+ SaveAndRestore<CFGBlock*> save_Block(Block), save_Succ(Succ);
+ SaveAndRestore<JumpTarget> save_continue(ContinueJumpTarget),
+ save_break(BreakJumpTarget);
+
+ // Create an empty block to represent the transition block for looping back
+ // to the head of the loop.
+ Block = 0;
+ assert(Succ == EntryConditionBlock);
+ Succ = createBlock();
+ Succ->setLoopTarget(W);
+ ContinueJumpTarget = JumpTarget(Succ, LoopBeginScopePos);
+
+ // All breaks should go to the code following the loop.
+ BreakJumpTarget = JumpTarget(LoopSuccessor, ScopePos);
+
+ // NULL out Block to force lazy instantiation of blocks for the body.
+ Block = NULL;
+
+ // Loop body should end with destructor of Condition variable (if any).
+ addAutomaticObjDtors(ScopePos, LoopBeginScopePos, W);
+
+ // If body is not a compound statement create implicit scope
+ // and add destructors.
+ if (!isa<CompoundStmt>(W->getBody()))
+ addLocalScopeAndDtors(W->getBody());
+
+ // Create the body. The returned block is the entry to the loop body.
+ CFGBlock *BodyBlock = addStmt(W->getBody());
+
+ if (!BodyBlock)
+ BodyBlock = ContinueJumpTarget.block; // can happen for "while(...) ;"
+ else if (Block) {
+ if (badCFG)
+ return 0;
+ }
+
+ // Add the loop body entry as a successor to the condition.
+ addSuccessor(ExitConditionBlock, KnownVal.isFalse() ? NULL : BodyBlock);
+ }
+
+ // Link up the condition block with the code that follows the loop. (the
+ // false branch).
+ addSuccessor(ExitConditionBlock, KnownVal.isTrue() ? NULL : LoopSuccessor);
+
+ // There can be no more statements in the condition block since we loop back
+ // to this block. NULL out Block to force lazy creation of another block.
+ Block = NULL;
+
+ // Return the condition block, which is the dominating block for the loop.
+ Succ = EntryConditionBlock;
+ return EntryConditionBlock;
+}
+
+
+CFGBlock *CFGBuilder::VisitObjCAtCatchStmt(ObjCAtCatchStmt *S) {
+ // FIXME: For now we pretend that @catch and the code it contains does not
+ // exit.
+ return Block;
+}
+
+CFGBlock *CFGBuilder::VisitObjCAtThrowStmt(ObjCAtThrowStmt *S) {
+ // FIXME: This isn't complete. We basically treat @throw like a return
+ // statement.
+
+ // If we were in the middle of a block we stop processing that block.
+ if (badCFG)
+ return 0;
+
+ // Create the new block.
+ Block = createBlock(false);
+
+ // The Exit block is the only successor.
+ addSuccessor(Block, &cfg->getExit());
+
+ // Add the statement to the block. This may create new blocks if S contains
+ // control-flow (short-circuit operations).
+ return VisitStmt(S, AddStmtChoice::AlwaysAdd);
+}
+
+CFGBlock *CFGBuilder::VisitCXXThrowExpr(CXXThrowExpr *T) {
+ // If we were in the middle of a block we stop processing that block.
+ if (badCFG)
+ return 0;
+
+ // Create the new block.
+ Block = createBlock(false);
+
+ if (TryTerminatedBlock)
+ // The current try statement is the only successor.
+ addSuccessor(Block, TryTerminatedBlock);
+ else
+ // otherwise the Exit block is the only successor.
+ addSuccessor(Block, &cfg->getExit());
+
+ // Add the statement to the block. This may create new blocks if S contains
+ // control-flow (short-circuit operations).
+ return VisitStmt(T, AddStmtChoice::AlwaysAdd);
+}
+
+CFGBlock *CFGBuilder::VisitDoStmt(DoStmt *D) {
+ CFGBlock *LoopSuccessor = NULL;
+
+ // "do...while" is a control-flow statement. Thus we stop processing the
+ // current block.
+ if (Block) {
+ if (badCFG)
+ return 0;
+ LoopSuccessor = Block;
+ } else
+ LoopSuccessor = Succ;
+
+ // Because of short-circuit evaluation, the condition of the loop can span
+ // multiple basic blocks. Thus we need the "Entry" and "Exit" blocks that
+ // evaluate the condition.
+ CFGBlock *ExitConditionBlock = createBlock(false);
+ CFGBlock *EntryConditionBlock = ExitConditionBlock;
+
+ // Set the terminator for the "exit" condition block.
+ ExitConditionBlock->setTerminator(D);
+
+ // Now add the actual condition to the condition block. Because the condition
+ // itself may contain control-flow, new blocks may be created.
+ if (Stmt *C = D->getCond()) {
+ Block = ExitConditionBlock;
+ EntryConditionBlock = addStmt(C);
+ if (Block) {
+ if (badCFG)
+ return 0;
+ }
+ }
+
+ // The condition block is the implicit successor for the loop body.
+ Succ = EntryConditionBlock;
+
+ // See if this is a known constant.
+ const TryResult &KnownVal = tryEvaluateBool(D->getCond());
+
+ // Process the loop body.
+ CFGBlock *BodyBlock = NULL;
+ {
+ assert(D->getBody());
+
+ // Save the current values for Block, Succ, and continue and break targets
+ SaveAndRestore<CFGBlock*> save_Block(Block), save_Succ(Succ);
+ SaveAndRestore<JumpTarget> save_continue(ContinueJumpTarget),
+ save_break(BreakJumpTarget);
+
+ // All continues within this loop should go to the condition block
+ ContinueJumpTarget = JumpTarget(EntryConditionBlock, ScopePos);
+
+ // All breaks should go to the code following the loop.
+ BreakJumpTarget = JumpTarget(LoopSuccessor, ScopePos);
+
+ // NULL out Block to force lazy instantiation of blocks for the body.
+ Block = NULL;
+
+ // If body is not a compound statement create implicit scope
+ // and add destructors.
+ if (!isa<CompoundStmt>(D->getBody()))
+ addLocalScopeAndDtors(D->getBody());
+
+ // Create the body. The returned block is the entry to the loop body.
+ BodyBlock = addStmt(D->getBody());
+
+ if (!BodyBlock)
+ BodyBlock = EntryConditionBlock; // can happen for "do ; while(...)"
+ else if (Block) {
+ if (badCFG)
+ return 0;
+ }
+
+ if (!KnownVal.isFalse()) {
+ // Add an intermediate block between the BodyBlock and the
+ // ExitConditionBlock to represent the "loop back" transition. Create an
+ // empty block to represent the transition block for looping back to the
+ // head of the loop.
+ // FIXME: Can we do this more efficiently without adding another block?
+ Block = NULL;
+ Succ = BodyBlock;
+ CFGBlock *LoopBackBlock = createBlock();
+ LoopBackBlock->setLoopTarget(D);
+
+ // Add the loop body entry as a successor to the condition.
+ addSuccessor(ExitConditionBlock, LoopBackBlock);
+ }
+ else
+ addSuccessor(ExitConditionBlock, NULL);
+ }
+
+ // Link up the condition block with the code that follows the loop.
+ // (the false branch).
+ addSuccessor(ExitConditionBlock, KnownVal.isTrue() ? NULL : LoopSuccessor);
+
+ // There can be no more statements in the body block(s) since we loop back to
+ // the body. NULL out Block to force lazy creation of another block.
+ Block = NULL;
+
+ // Return the loop body, which is the dominating block for the loop.
+ Succ = BodyBlock;
+ return BodyBlock;
+}
+
+CFGBlock *CFGBuilder::VisitContinueStmt(ContinueStmt *C) {
+ // "continue" is a control-flow statement. Thus we stop processing the
+ // current block.
+ if (badCFG)
+ return 0;
+
+ // Now create a new block that ends with the continue statement.
+ Block = createBlock(false);
+ Block->setTerminator(C);
+
+ // If there is no target for the continue, then we are looking at an
+ // incomplete AST. This means the CFG cannot be constructed.
+ if (ContinueJumpTarget.block) {
+ addAutomaticObjDtors(ScopePos, ContinueJumpTarget.scopePosition, C);
+ addSuccessor(Block, ContinueJumpTarget.block);
+ } else
+ badCFG = true;
+
+ return Block;
+}
+
+CFGBlock *CFGBuilder::VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *E,
+ AddStmtChoice asc) {
+
+ if (asc.alwaysAdd(*this, E)) {
+ autoCreateBlock();
+ appendStmt(Block, E);
+ }
+
+ // VLA types have expressions that must be evaluated.
+ CFGBlock *lastBlock = Block;
+
+ if (E->isArgumentType()) {
+ for (const VariableArrayType *VA =FindVA(E->getArgumentType().getTypePtr());
+ VA != 0; VA = FindVA(VA->getElementType().getTypePtr()))
+ lastBlock = addStmt(VA->getSizeExpr());
+ }
+ return lastBlock;
+}
+
+/// VisitStmtExpr - Utility method to handle (nested) statement
+/// expressions (a GCC extension).
+CFGBlock *CFGBuilder::VisitStmtExpr(StmtExpr *SE, AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, SE)) {
+ autoCreateBlock();
+ appendStmt(Block, SE);
+ }
+ return VisitCompoundStmt(SE->getSubStmt());
+}
+
+CFGBlock *CFGBuilder::VisitSwitchStmt(SwitchStmt *Terminator) {
+ // "switch" is a control-flow statement. Thus we stop processing the current
+ // block.
+ CFGBlock *SwitchSuccessor = NULL;
+
+ // Save local scope position because in case of condition variable ScopePos
+ // won't be restored when traversing AST.
+ SaveAndRestore<LocalScope::const_iterator> save_scope_pos(ScopePos);
+
+ // Create local scope for possible condition variable.
+ // Store scope position. Add implicit destructor.
+ if (VarDecl *VD = Terminator->getConditionVariable()) {
+ LocalScope::const_iterator SwitchBeginScopePos = ScopePos;
+ addLocalScopeForVarDecl(VD);
+ addAutomaticObjDtors(ScopePos, SwitchBeginScopePos, Terminator);
+ }
+
+ if (Block) {
+ if (badCFG)
+ return 0;
+ SwitchSuccessor = Block;
+ } else SwitchSuccessor = Succ;
+
+ // Save the current "switch" context.
+ SaveAndRestore<CFGBlock*> save_switch(SwitchTerminatedBlock),
+ save_default(DefaultCaseBlock);
+ SaveAndRestore<JumpTarget> save_break(BreakJumpTarget);
+
+ // Set the "default" case to be the block after the switch statement. If the
+ // switch statement contains a "default:", this value will be overwritten with
+ // the block for that code.
+ DefaultCaseBlock = SwitchSuccessor;
+
+ // Create a new block that will contain the switch statement.
+ SwitchTerminatedBlock = createBlock(false);
+
+ // Now process the switch body. The code after the switch is the implicit
+ // successor.
+ Succ = SwitchSuccessor;
+ BreakJumpTarget = JumpTarget(SwitchSuccessor, ScopePos);
+
+ // When visiting the body, the case statements should automatically get linked
+ // up to the switch. We also don't keep a pointer to the body, since all
+ // control-flow from the switch goes to case/default statements.
+ assert(Terminator->getBody() && "switch must contain a non-NULL body");
+ Block = NULL;
+
+ // For pruning unreachable case statements, save the current state
+ // for tracking the condition value.
+ SaveAndRestore<bool> save_switchExclusivelyCovered(switchExclusivelyCovered,
+ false);
+
+ // Determine if the switch condition can be explicitly evaluated.
+ assert(Terminator->getCond() && "switch condition must be non-NULL");
+ Expr::EvalResult result;
+ bool b = tryEvaluate(Terminator->getCond(), result);
+ SaveAndRestore<Expr::EvalResult*> save_switchCond(switchCond,
+ b ? &result : 0);
+
+ // If body is not a compound statement create implicit scope
+ // and add destructors.
+ if (!isa<CompoundStmt>(Terminator->getBody()))
+ addLocalScopeAndDtors(Terminator->getBody());
+
+ addStmt(Terminator->getBody());
+ if (Block) {
+ if (badCFG)
+ return 0;
+ }
+
+ // If we have no "default:" case, the default transition is to the code
+ // following the switch body. Moreover, take into account if all the
+ // cases of a switch are covered (e.g., switching on an enum value).
+ addSuccessor(SwitchTerminatedBlock,
+ switchExclusivelyCovered || Terminator->isAllEnumCasesCovered()
+ ? 0 : DefaultCaseBlock);
+
+ // Add the terminator and condition in the switch block.
+ SwitchTerminatedBlock->setTerminator(Terminator);
+ Block = SwitchTerminatedBlock;
+ Block = addStmt(Terminator->getCond());
+
+ // Finally, if the SwitchStmt contains a condition variable, add both the
+ // SwitchStmt and the condition variable initialization to the CFG.
+ if (VarDecl *VD = Terminator->getConditionVariable()) {
+ if (Expr *Init = VD->getInit()) {
+ autoCreateBlock();
+ appendStmt(Block, Terminator->getConditionVariableDeclStmt());
+ addStmt(Init);
+ }
+ }
+
+ return Block;
+}
+
+static bool shouldAddCase(bool &switchExclusivelyCovered,
+ const Expr::EvalResult *switchCond,
+ const CaseStmt *CS,
+ ASTContext &Ctx) {
+ if (!switchCond)
+ return true;
+
+ bool addCase = false;
+
+ if (!switchExclusivelyCovered) {
+ if (switchCond->Val.isInt()) {
+ // Evaluate the LHS of the case value.
+ const llvm::APSInt &lhsInt = CS->getLHS()->EvaluateKnownConstInt(Ctx);
+ const llvm::APSInt &condInt = switchCond->Val.getInt();
+
+ if (condInt == lhsInt) {
+ addCase = true;
+ switchExclusivelyCovered = true;
+ }
+ else if (condInt < lhsInt) {
+ if (const Expr *RHS = CS->getRHS()) {
+ // Evaluate the RHS of the case value.
+ const llvm::APSInt &V2 = RHS->EvaluateKnownConstInt(Ctx);
+ if (V2 <= condInt) {
+ addCase = true;
+ switchExclusivelyCovered = true;
+ }
+ }
+ }
+ }
+ else
+ addCase = true;
+ }
+ return addCase;
+}
+
+CFGBlock *CFGBuilder::VisitCaseStmt(CaseStmt *CS) {
+ // CaseStmts are essentially labels, so they are the first statement in a
+ // block.
+ CFGBlock *TopBlock = 0, *LastBlock = 0;
+
+ if (Stmt *Sub = CS->getSubStmt()) {
+ // For deeply nested chains of CaseStmts, instead of doing a recursion
+ // (which can blow out the stack), manually unroll and create blocks
+ // along the way.
+ while (isa<CaseStmt>(Sub)) {
+ CFGBlock *currentBlock = createBlock(false);
+ currentBlock->setLabel(CS);
+
+ if (TopBlock)
+ addSuccessor(LastBlock, currentBlock);
+ else
+ TopBlock = currentBlock;
+
+ addSuccessor(SwitchTerminatedBlock,
+ shouldAddCase(switchExclusivelyCovered, switchCond,
+ CS, *Context)
+ ? currentBlock : 0);
+
+ LastBlock = currentBlock;
+ CS = cast<CaseStmt>(Sub);
+ Sub = CS->getSubStmt();
+ }
+
+ addStmt(Sub);
+ }
+
+ CFGBlock *CaseBlock = Block;
+ if (!CaseBlock)
+ CaseBlock = createBlock();
+
+ // Cases statements partition blocks, so this is the top of the basic block we
+ // were processing (the "case XXX:" is the label).
+ CaseBlock->setLabel(CS);
+
+ if (badCFG)
+ return 0;
+
+ // Add this block to the list of successors for the block with the switch
+ // statement.
+ assert(SwitchTerminatedBlock);
+ addSuccessor(SwitchTerminatedBlock,
+ shouldAddCase(switchExclusivelyCovered, switchCond,
+ CS, *Context)
+ ? CaseBlock : 0);
+
+ // We set Block to NULL to allow lazy creation of a new block (if necessary)
+ Block = NULL;
+
+ if (TopBlock) {
+ addSuccessor(LastBlock, CaseBlock);
+ Succ = TopBlock;
+ } else {
+ // This block is now the implicit successor of other blocks.
+ Succ = CaseBlock;
+ }
+
+ return Succ;
+}
+
+CFGBlock *CFGBuilder::VisitDefaultStmt(DefaultStmt *Terminator) {
+ if (Terminator->getSubStmt())
+ addStmt(Terminator->getSubStmt());
+
+ DefaultCaseBlock = Block;
+
+ if (!DefaultCaseBlock)
+ DefaultCaseBlock = createBlock();
+
+ // Default statements partition blocks, so this is the top of the basic block
+ // we were processing (the "default:" is the label).
+ DefaultCaseBlock->setLabel(Terminator);
+
+ if (badCFG)
+ return 0;
+
+ // Unlike case statements, we don't add the default block to the successors
+ // for the switch statement immediately. This is done when we finish
+ // processing the switch statement. This allows for the default case
+ // (including a fall-through to the code after the switch statement) to always
+ // be the last successor of a switch-terminated block.
+
+ // We set Block to NULL to allow lazy creation of a new block (if necessary)
+ Block = NULL;
+
+ // This block is now the implicit successor of other blocks.
+ Succ = DefaultCaseBlock;
+
+ return DefaultCaseBlock;
+}
+
+CFGBlock *CFGBuilder::VisitCXXTryStmt(CXXTryStmt *Terminator) {
+ // "try"/"catch" is a control-flow statement. Thus we stop processing the
+ // current block.
+ CFGBlock *TrySuccessor = NULL;
+
+ if (Block) {
+ if (badCFG)
+ return 0;
+ TrySuccessor = Block;
+ } else TrySuccessor = Succ;
+
+ CFGBlock *PrevTryTerminatedBlock = TryTerminatedBlock;
+
+ // Create a new block that will contain the try statement.
+ CFGBlock *NewTryTerminatedBlock = createBlock(false);
+ // Add the terminator in the try block.
+ NewTryTerminatedBlock->setTerminator(Terminator);
+
+ bool HasCatchAll = false;
+ for (unsigned h = 0; h <Terminator->getNumHandlers(); ++h) {
+ // The code after the try is the implicit successor.
+ Succ = TrySuccessor;
+ CXXCatchStmt *CS = Terminator->getHandler(h);
+ if (CS->getExceptionDecl() == 0) {
+ HasCatchAll = true;
+ }
+ Block = NULL;
+ CFGBlock *CatchBlock = VisitCXXCatchStmt(CS);
+ if (CatchBlock == 0)
+ return 0;
+ // Add this block to the list of successors for the block with the try
+ // statement.
+ addSuccessor(NewTryTerminatedBlock, CatchBlock);
+ }
+ if (!HasCatchAll) {
+ if (PrevTryTerminatedBlock)
+ addSuccessor(NewTryTerminatedBlock, PrevTryTerminatedBlock);
+ else
+ addSuccessor(NewTryTerminatedBlock, &cfg->getExit());
+ }
+
+ // The code after the try is the implicit successor.
+ Succ = TrySuccessor;
+
+ // Save the current "try" context.
+ SaveAndRestore<CFGBlock*> save_try(TryTerminatedBlock, NewTryTerminatedBlock);
+ cfg->addTryDispatchBlock(TryTerminatedBlock);
+
+ assert(Terminator->getTryBlock() && "try must contain a non-NULL body");
+ Block = NULL;
+ Block = addStmt(Terminator->getTryBlock());
+ return Block;
+}
+
+CFGBlock *CFGBuilder::VisitCXXCatchStmt(CXXCatchStmt *CS) {
+ // CXXCatchStmt are treated like labels, so they are the first statement in a
+ // block.
+
+ // Save local scope position because in case of exception variable ScopePos
+ // won't be restored when traversing AST.
+ SaveAndRestore<LocalScope::const_iterator> save_scope_pos(ScopePos);
+
+ // Create local scope for possible exception variable.
+ // Store scope position. Add implicit destructor.
+ if (VarDecl *VD = CS->getExceptionDecl()) {
+ LocalScope::const_iterator BeginScopePos = ScopePos;
+ addLocalScopeForVarDecl(VD);
+ addAutomaticObjDtors(ScopePos, BeginScopePos, CS);
+ }
+
+ if (CS->getHandlerBlock())
+ addStmt(CS->getHandlerBlock());
+
+ CFGBlock *CatchBlock = Block;
+ if (!CatchBlock)
+ CatchBlock = createBlock();
+
+ // CXXCatchStmt is more than just a label. They have semantic meaning
+ // as well, as they implicitly "initialize" the catch variable. Add
+ // it to the CFG as a CFGElement so that the control-flow of these
+ // semantics gets captured.
+ appendStmt(CatchBlock, CS);
+
+ // Also add the CXXCatchStmt as a label, to mirror handling of regular
+ // labels.
+ CatchBlock->setLabel(CS);
+
+ // Bail out if the CFG is bad.
+ if (badCFG)
+ return 0;
+
+ // We set Block to NULL to allow lazy creation of a new block (if necessary)
+ Block = NULL;
+
+ return CatchBlock;
+}
+
+CFGBlock *CFGBuilder::VisitCXXForRangeStmt(CXXForRangeStmt *S) {
+ // C++0x for-range statements are specified as [stmt.ranged]:
+ //
+ // {
+ // auto && __range = range-init;
+ // for ( auto __begin = begin-expr,
+ // __end = end-expr;
+ // __begin != __end;
+ // ++__begin ) {
+ // for-range-declaration = *__begin;
+ // statement
+ // }
+ // }
+
+ // Save local scope position before the addition of the implicit variables.
+ SaveAndRestore<LocalScope::const_iterator> save_scope_pos(ScopePos);
+
+ // Create local scopes and destructors for range, begin and end variables.
+ if (Stmt *Range = S->getRangeStmt())
+ addLocalScopeForStmt(Range);
+ if (Stmt *BeginEnd = S->getBeginEndStmt())
+ addLocalScopeForStmt(BeginEnd);
+ addAutomaticObjDtors(ScopePos, save_scope_pos.get(), S);
+
+ LocalScope::const_iterator ContinueScopePos = ScopePos;
+
+ // "for" is a control-flow statement. Thus we stop processing the current
+ // block.
+ CFGBlock *LoopSuccessor = NULL;
+ if (Block) {
+ if (badCFG)
+ return 0;
+ LoopSuccessor = Block;
+ } else
+ LoopSuccessor = Succ;
+
+ // Save the current value for the break targets.
+ // All breaks should go to the code following the loop.
+ SaveAndRestore<JumpTarget> save_break(BreakJumpTarget);
+ BreakJumpTarget = JumpTarget(LoopSuccessor, ScopePos);
+
+ // The block for the __begin != __end expression.
+ CFGBlock *ConditionBlock = createBlock(false);
+ ConditionBlock->setTerminator(S);
+
+ // Now add the actual condition to the condition block.
+ if (Expr *C = S->getCond()) {
+ Block = ConditionBlock;
+ CFGBlock *BeginConditionBlock = addStmt(C);
+ if (badCFG)
+ return 0;
+ assert(BeginConditionBlock == ConditionBlock &&
+ "condition block in for-range was unexpectedly complex");
+ (void)BeginConditionBlock;
+ }
+
+ // The condition block is the implicit successor for the loop body as well as
+ // any code above the loop.
+ Succ = ConditionBlock;
+
+ // See if this is a known constant.
+ TryResult KnownVal(true);
+
+ if (S->getCond())
+ KnownVal = tryEvaluateBool(S->getCond());
+
+ // Now create the loop body.
+ {
+ assert(S->getBody());
+
+ // Save the current values for Block, Succ, and continue targets.
+ SaveAndRestore<CFGBlock*> save_Block(Block), save_Succ(Succ);
+ SaveAndRestore<JumpTarget> save_continue(ContinueJumpTarget);
+
+ // Generate increment code in its own basic block. This is the target of
+ // continue statements.
+ Block = 0;
+ Succ = addStmt(S->getInc());
+ ContinueJumpTarget = JumpTarget(Succ, ContinueScopePos);
+
+ // The starting block for the loop increment is the block that should
+ // represent the 'loop target' for looping back to the start of the loop.
+ ContinueJumpTarget.block->setLoopTarget(S);
+
+ // Finish up the increment block and prepare to start the loop body.
+ assert(Block);
+ if (badCFG)
+ return 0;
+ Block = 0;
+
+
+ // Add implicit scope and dtors for loop variable.
+ addLocalScopeAndDtors(S->getLoopVarStmt());
+
+ // Populate a new block to contain the loop body and loop variable.
+ Block = addStmt(S->getBody());
+ if (badCFG)
+ return 0;
+ Block = addStmt(S->getLoopVarStmt());
+ if (badCFG)
+ return 0;
+
+ // This new body block is a successor to our condition block.
+ addSuccessor(ConditionBlock, KnownVal.isFalse() ? 0 : Block);
+ }
+
+ // Link up the condition block with the code that follows the loop (the
+ // false branch).
+ addSuccessor(ConditionBlock, KnownVal.isTrue() ? 0 : LoopSuccessor);
+
+ // Add the initialization statements.
+ Block = createBlock();
+ addStmt(S->getBeginEndStmt());
+ return addStmt(S->getRangeStmt());
+}
+
+CFGBlock *CFGBuilder::VisitExprWithCleanups(ExprWithCleanups *E,
+ AddStmtChoice asc) {
+ if (BuildOpts.AddImplicitDtors) {
+ // If adding implicit destructors visit the full expression for adding
+ // destructors of temporaries.
+ VisitForTemporaryDtors(E->getSubExpr());
+
+ // Full expression has to be added as CFGStmt so it will be sequenced
+ // before destructors of it's temporaries.
+ asc = asc.withAlwaysAdd(true);
+ }
+ return Visit(E->getSubExpr(), asc);
+}
+
+CFGBlock *CFGBuilder::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E,
+ AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, E)) {
+ autoCreateBlock();
+ appendStmt(Block, E);
+
+ // We do not want to propagate the AlwaysAdd property.
+ asc = asc.withAlwaysAdd(false);
+ }
+ return Visit(E->getSubExpr(), asc);
+}
+
+CFGBlock *CFGBuilder::VisitCXXConstructExpr(CXXConstructExpr *C,
+ AddStmtChoice asc) {
+ autoCreateBlock();
+ appendStmt(Block, C);
+
+ return VisitChildren(C);
+}
+
+CFGBlock *CFGBuilder::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E,
+ AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, E)) {
+ autoCreateBlock();
+ appendStmt(Block, E);
+ // We do not want to propagate the AlwaysAdd property.
+ asc = asc.withAlwaysAdd(false);
+ }
+ return Visit(E->getSubExpr(), asc);
+}
+
+CFGBlock *CFGBuilder::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *C,
+ AddStmtChoice asc) {
+ autoCreateBlock();
+ appendStmt(Block, C);
+ return VisitChildren(C);
+}
+
+CFGBlock *CFGBuilder::VisitImplicitCastExpr(ImplicitCastExpr *E,
+ AddStmtChoice asc) {
+ if (asc.alwaysAdd(*this, E)) {
+ autoCreateBlock();
+ appendStmt(Block, E);
+ }
+ return Visit(E->getSubExpr(), AddStmtChoice());
+}
+
+CFGBlock *CFGBuilder::VisitIndirectGotoStmt(IndirectGotoStmt *I) {
+ // Lazily create the indirect-goto dispatch block if there isn't one already.
+ CFGBlock *IBlock = cfg->getIndirectGotoBlock();
+
+ if (!IBlock) {
+ IBlock = createBlock(false);
+ cfg->setIndirectGotoBlock(IBlock);
+ }
+
+ // IndirectGoto is a control-flow statement. Thus we stop processing the
+ // current block and create a new one.
+ if (badCFG)
+ return 0;
+
+ Block = createBlock(false);
+ Block->setTerminator(I);
+ addSuccessor(Block, IBlock);
+ return addStmt(I->getTarget());
+}
+
+CFGBlock *CFGBuilder::VisitForTemporaryDtors(Stmt *E, bool BindToTemporary) {
+tryAgain:
+ if (!E) {
+ badCFG = true;
+ return NULL;
+ }
+ switch (E->getStmtClass()) {
+ default:
+ return VisitChildrenForTemporaryDtors(E);
+
+ case Stmt::BinaryOperatorClass:
+ return VisitBinaryOperatorForTemporaryDtors(cast<BinaryOperator>(E));
+
+ case Stmt::CXXBindTemporaryExprClass:
+ return VisitCXXBindTemporaryExprForTemporaryDtors(
+ cast<CXXBindTemporaryExpr>(E), BindToTemporary);
+
+ case Stmt::BinaryConditionalOperatorClass:
+ case Stmt::ConditionalOperatorClass:
+ return VisitConditionalOperatorForTemporaryDtors(
+ cast<AbstractConditionalOperator>(E), BindToTemporary);
+
+ case Stmt::ImplicitCastExprClass:
+ // For implicit cast we want BindToTemporary to be passed further.
+ E = cast<CastExpr>(E)->getSubExpr();
+ goto tryAgain;
+
+ case Stmt::ParenExprClass:
+ E = cast<ParenExpr>(E)->getSubExpr();
+ goto tryAgain;
+
+ case Stmt::MaterializeTemporaryExprClass:
+ E = cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr();
+ goto tryAgain;
+ }
+}
+
+CFGBlock *CFGBuilder::VisitChildrenForTemporaryDtors(Stmt *E) {
+ // When visiting children for destructors we want to visit them in reverse
+ // order. Because there's no reverse iterator for children must to reverse
+ // them in helper vector.
+ typedef SmallVector<Stmt *, 4> ChildrenVect;
+ ChildrenVect ChildrenRev;
+ for (Stmt::child_range I = E->children(); I; ++I) {
+ if (*I) ChildrenRev.push_back(*I);
+ }
+
+ CFGBlock *B = Block;
+ for (ChildrenVect::reverse_iterator I = ChildrenRev.rbegin(),
+ L = ChildrenRev.rend(); I != L; ++I) {
+ if (CFGBlock *R = VisitForTemporaryDtors(*I))
+ B = R;
+ }
+ return B;
+}
+
+CFGBlock *CFGBuilder::VisitBinaryOperatorForTemporaryDtors(BinaryOperator *E) {
+ if (E->isLogicalOp()) {
+ // Destructors for temporaries in LHS expression should be called after
+ // those for RHS expression. Even if this will unnecessarily create a block,
+ // this block will be used at least by the full expression.
+ autoCreateBlock();
+ CFGBlock *ConfluenceBlock = VisitForTemporaryDtors(E->getLHS());
+ if (badCFG)
+ return NULL;
+
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ CFGBlock *RHSBlock = VisitForTemporaryDtors(E->getRHS());
+
+ if (RHSBlock) {
+ if (badCFG)
+ return NULL;
+
+ // If RHS expression did produce destructors we need to connect created
+ // blocks to CFG in same manner as for binary operator itself.
+ CFGBlock *LHSBlock = createBlock(false);
+ LHSBlock->setTerminator(CFGTerminator(E, true));
+
+ // For binary operator LHS block is before RHS in list of predecessors
+ // of ConfluenceBlock.
+ std::reverse(ConfluenceBlock->pred_begin(),
+ ConfluenceBlock->pred_end());
+
+ // See if this is a known constant.
+ TryResult KnownVal = tryEvaluateBool(E->getLHS());
+ if (KnownVal.isKnown() && (E->getOpcode() == BO_LOr))
+ KnownVal.negate();
+
+ // Link LHSBlock with RHSBlock exactly the same way as for binary operator
+ // itself.
+ if (E->getOpcode() == BO_LOr) {
+ addSuccessor(LHSBlock, KnownVal.isTrue() ? NULL : ConfluenceBlock);
+ addSuccessor(LHSBlock, KnownVal.isFalse() ? NULL : RHSBlock);
+ } else {
+ assert (E->getOpcode() == BO_LAnd);
+ addSuccessor(LHSBlock, KnownVal.isFalse() ? NULL : RHSBlock);
+ addSuccessor(LHSBlock, KnownVal.isTrue() ? NULL : ConfluenceBlock);
+ }
+
+ Block = LHSBlock;
+ return LHSBlock;
+ }
+
+ Block = ConfluenceBlock;
+ return ConfluenceBlock;
+ }
+
+ if (E->isAssignmentOp()) {
+ // For assignment operator (=) LHS expression is visited
+ // before RHS expression. For destructors visit them in reverse order.
+ CFGBlock *RHSBlock = VisitForTemporaryDtors(E->getRHS());
+ CFGBlock *LHSBlock = VisitForTemporaryDtors(E->getLHS());
+ return LHSBlock ? LHSBlock : RHSBlock;
+ }
+
+ // For any other binary operator RHS expression is visited before
+ // LHS expression (order of children). For destructors visit them in reverse
+ // order.
+ CFGBlock *LHSBlock = VisitForTemporaryDtors(E->getLHS());
+ CFGBlock *RHSBlock = VisitForTemporaryDtors(E->getRHS());
+ return RHSBlock ? RHSBlock : LHSBlock;
+}
+
+CFGBlock *CFGBuilder::VisitCXXBindTemporaryExprForTemporaryDtors(
+ CXXBindTemporaryExpr *E, bool BindToTemporary) {
+ // First add destructors for temporaries in subexpression.
+ CFGBlock *B = VisitForTemporaryDtors(E->getSubExpr());
+ if (!BindToTemporary) {
+ // If lifetime of temporary is not prolonged (by assigning to constant
+ // reference) add destructor for it.
+
+ // If the destructor is marked as a no-return destructor, we need to create
+ // a new block for the destructor which does not have as a successor
+ // anything built thus far. Control won't flow out of this block.
+ const CXXDestructorDecl *Dtor = E->getTemporary()->getDestructor();
+ if (cast<FunctionType>(Dtor->getType())->getNoReturnAttr())
+ Block = createNoReturnBlock();
+ else
+ autoCreateBlock();
+
+ appendTemporaryDtor(Block, E);
+ B = Block;
+ }
+ return B;
+}
+
+CFGBlock *CFGBuilder::VisitConditionalOperatorForTemporaryDtors(
+ AbstractConditionalOperator *E, bool BindToTemporary) {
+ // First add destructors for condition expression. Even if this will
+ // unnecessarily create a block, this block will be used at least by the full
+ // expression.
+ autoCreateBlock();
+ CFGBlock *ConfluenceBlock = VisitForTemporaryDtors(E->getCond());
+ if (badCFG)
+ return NULL;
+ if (BinaryConditionalOperator *BCO
+ = dyn_cast<BinaryConditionalOperator>(E)) {
+ ConfluenceBlock = VisitForTemporaryDtors(BCO->getCommon());
+ if (badCFG)
+ return NULL;
+ }
+
+ // Try to add block with destructors for LHS expression.
+ CFGBlock *LHSBlock = NULL;
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ LHSBlock = VisitForTemporaryDtors(E->getTrueExpr(), BindToTemporary);
+ if (badCFG)
+ return NULL;
+
+ // Try to add block with destructors for RHS expression;
+ Succ = ConfluenceBlock;
+ Block = NULL;
+ CFGBlock *RHSBlock = VisitForTemporaryDtors(E->getFalseExpr(),
+ BindToTemporary);
+ if (badCFG)
+ return NULL;
+
+ if (!RHSBlock && !LHSBlock) {
+ // If neither LHS nor RHS expression had temporaries to destroy don't create
+ // more blocks.
+ Block = ConfluenceBlock;
+ return Block;
+ }
+
+ Block = createBlock(false);
+ Block->setTerminator(CFGTerminator(E, true));
+
+ // See if this is a known constant.
+ const TryResult &KnownVal = tryEvaluateBool(E->getCond());
+
+ if (LHSBlock) {
+ addSuccessor(Block, KnownVal.isFalse() ? NULL : LHSBlock);
+ } else if (KnownVal.isFalse()) {
+ addSuccessor(Block, NULL);
+ } else {
+ addSuccessor(Block, ConfluenceBlock);
+ std::reverse(ConfluenceBlock->pred_begin(), ConfluenceBlock->pred_end());
+ }
+
+ if (!RHSBlock)
+ RHSBlock = ConfluenceBlock;
+ addSuccessor(Block, KnownVal.isTrue() ? NULL : RHSBlock);
+
+ return Block;
+}
+
+} // end anonymous namespace
+
+/// createBlock - Constructs and adds a new CFGBlock to the CFG. The block has
+/// no successors or predecessors. If this is the first block created in the
+/// CFG, it is automatically set to be the Entry and Exit of the CFG.
+CFGBlock *CFG::createBlock() {
+ bool first_block = begin() == end();
+
+ // Create the block.
+ CFGBlock *Mem = getAllocator().Allocate<CFGBlock>();
+ new (Mem) CFGBlock(NumBlockIDs++, BlkBVC, this);
+ Blocks.push_back(Mem, BlkBVC);
+
+ // If this is the first block, set it as the Entry and Exit.
+ if (first_block)
+ Entry = Exit = &back();
+
+ // Return the block.
+ return &back();
+}
+
+/// buildCFG - Constructs a CFG from an AST. Ownership of the returned
+/// CFG is returned to the caller.
+CFG* CFG::buildCFG(const Decl *D, Stmt *Statement, ASTContext *C,
+ const BuildOptions &BO) {
+ CFGBuilder Builder(C, BO);
+ return Builder.buildCFG(D, Statement);
+}
+
+const CXXDestructorDecl *
+CFGImplicitDtor::getDestructorDecl(ASTContext &astContext) const {
+ switch (getKind()) {
+ case CFGElement::Invalid:
+ case CFGElement::Statement:
+ case CFGElement::Initializer:
+ llvm_unreachable("getDestructorDecl should only be used with "
+ "ImplicitDtors");
+ case CFGElement::AutomaticObjectDtor: {
+ const VarDecl *var = cast<CFGAutomaticObjDtor>(this)->getVarDecl();
+ QualType ty = var->getType();
+ ty = ty.getNonReferenceType();
+ while (const ArrayType *arrayType = astContext.getAsArrayType(ty)) {
+ ty = arrayType->getElementType();
+ }
+ const RecordType *recordType = ty->getAs<RecordType>();
+ const CXXRecordDecl *classDecl =
+ cast<CXXRecordDecl>(recordType->getDecl());
+ return classDecl->getDestructor();
+ }
+ case CFGElement::TemporaryDtor: {
+ const CXXBindTemporaryExpr *bindExpr =
+ cast<CFGTemporaryDtor>(this)->getBindTemporaryExpr();
+ const CXXTemporary *temp = bindExpr->getTemporary();
+ return temp->getDestructor();
+ }
+ case CFGElement::BaseDtor:
+ case CFGElement::MemberDtor:
+
+ // Not yet supported.
+ return 0;
+ }
+ llvm_unreachable("getKind() returned bogus value");
+}
+
+bool CFGImplicitDtor::isNoReturn(ASTContext &astContext) const {
+ if (const CXXDestructorDecl *cdecl = getDestructorDecl(astContext)) {
+ QualType ty = cdecl->getType();
+ return cast<FunctionType>(ty)->getNoReturnAttr();
+ }
+ return false;
+}
+
+//===----------------------------------------------------------------------===//
+// CFG: Queries for BlkExprs.
+//===----------------------------------------------------------------------===//
+
+namespace {
+ typedef llvm::DenseMap<const Stmt*,unsigned> BlkExprMapTy;
+}
+
+static void FindSubExprAssignments(const Stmt *S,
+ llvm::SmallPtrSet<const Expr*,50>& Set) {
+ if (!S)
+ return;
+
+ for (Stmt::const_child_range I = S->children(); I; ++I) {
+ const Stmt *child = *I;
+ if (!child)
+ continue;
+
+ if (const BinaryOperator* B = dyn_cast<BinaryOperator>(child))
+ if (B->isAssignmentOp()) Set.insert(B);
+
+ FindSubExprAssignments(child, Set);
+ }
+}
+
+static BlkExprMapTy* PopulateBlkExprMap(CFG& cfg) {
+ BlkExprMapTy* M = new BlkExprMapTy();
+
+ // Look for assignments that are used as subexpressions. These are the only
+ // assignments that we want to *possibly* register as a block-level
+ // expression. Basically, if an assignment occurs both in a subexpression and
+ // at the block-level, it is a block-level expression.
+ llvm::SmallPtrSet<const Expr*,50> SubExprAssignments;
+
+ for (CFG::iterator I=cfg.begin(), E=cfg.end(); I != E; ++I)
+ for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI)
+ if (const CFGStmt *S = BI->getAs<CFGStmt>())
+ FindSubExprAssignments(S->getStmt(), SubExprAssignments);
+
+ for (CFG::iterator I=cfg.begin(), E=cfg.end(); I != E; ++I) {
+
+ // Iterate over the statements again on identify the Expr* and Stmt* at the
+ // block-level that are block-level expressions.
+
+ for (CFGBlock::iterator BI=(*I)->begin(), EI=(*I)->end(); BI != EI; ++BI) {
+ const CFGStmt *CS = BI->getAs<CFGStmt>();
+ if (!CS)
+ continue;
+ if (const Expr *Exp = dyn_cast<Expr>(CS->getStmt())) {
+ assert((Exp->IgnoreParens() == Exp) && "No parens on block-level exps");
+
+ if (const BinaryOperator* B = dyn_cast<BinaryOperator>(Exp)) {
+ // Assignment expressions that are not nested within another
+ // expression are really "statements" whose value is never used by
+ // another expression.
+ if (B->isAssignmentOp() && !SubExprAssignments.count(Exp))
+ continue;
+ } else if (const StmtExpr *SE = dyn_cast<StmtExpr>(Exp)) {
+ // Special handling for statement expressions. The last statement in
+ // the statement expression is also a block-level expr.
+ const CompoundStmt *C = SE->getSubStmt();
+ if (!C->body_empty()) {
+ const Stmt *Last = C->body_back();
+ if (const Expr *LastEx = dyn_cast<Expr>(Last))
+ Last = LastEx->IgnoreParens();
+ unsigned x = M->size();
+ (*M)[Last] = x;
+ }
+ }
+
+ unsigned x = M->size();
+ (*M)[Exp] = x;
+ }
+ }
+
+ // Look at terminators. The condition is a block-level expression.
+
+ Stmt *S = (*I)->getTerminatorCondition();
+
+ if (S && M->find(S) == M->end()) {
+ unsigned x = M->size();
+ (*M)[S] = x;
+ }
+ }
+
+ return M;
+}
+
+CFG::BlkExprNumTy CFG::getBlkExprNum(const Stmt *S) {
+ assert(S != NULL);
+ if (!BlkExprMap) { BlkExprMap = (void*) PopulateBlkExprMap(*this); }
+
+ BlkExprMapTy* M = reinterpret_cast<BlkExprMapTy*>(BlkExprMap);
+ BlkExprMapTy::iterator I = M->find(S);
+ return (I == M->end()) ? CFG::BlkExprNumTy() : CFG::BlkExprNumTy(I->second);
+}
+
+unsigned CFG::getNumBlkExprs() {
+ if (const BlkExprMapTy* M = reinterpret_cast<const BlkExprMapTy*>(BlkExprMap))
+ return M->size();
+
+ // We assume callers interested in the number of BlkExprs will want
+ // the map constructed if it doesn't already exist.
+ BlkExprMap = (void*) PopulateBlkExprMap(*this);
+ return reinterpret_cast<BlkExprMapTy*>(BlkExprMap)->size();
+}
+
+//===----------------------------------------------------------------------===//
+// Filtered walking of the CFG.
+//===----------------------------------------------------------------------===//
+
+bool CFGBlock::FilterEdge(const CFGBlock::FilterOptions &F,
+ const CFGBlock *From, const CFGBlock *To) {
+
+ if (To && F.IgnoreDefaultsWithCoveredEnums) {
+ // If the 'To' has no label or is labeled but the label isn't a
+ // CaseStmt then filter this edge.
+ if (const SwitchStmt *S =
+ dyn_cast_or_null<SwitchStmt>(From->getTerminator().getStmt())) {
+ if (S->isAllEnumCasesCovered()) {
+ const Stmt *L = To->getLabel();
+ if (!L || !isa<CaseStmt>(L))
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+//===----------------------------------------------------------------------===//
+// Cleanup: CFG dstor.
+//===----------------------------------------------------------------------===//
+
+CFG::~CFG() {
+ delete reinterpret_cast<const BlkExprMapTy*>(BlkExprMap);
+}
+
+//===----------------------------------------------------------------------===//
+// CFG pretty printing
+//===----------------------------------------------------------------------===//
+
+namespace {
+
+class StmtPrinterHelper : public PrinterHelper {
+ typedef llvm::DenseMap<const Stmt*,std::pair<unsigned,unsigned> > StmtMapTy;
+ typedef llvm::DenseMap<const Decl*,std::pair<unsigned,unsigned> > DeclMapTy;
+ StmtMapTy StmtMap;
+ DeclMapTy DeclMap;
+ signed currentBlock;
+ unsigned currentStmt;
+ const LangOptions &LangOpts;
+public:
+
+ StmtPrinterHelper(const CFG* cfg, const LangOptions &LO)
+ : currentBlock(0), currentStmt(0), LangOpts(LO)
+ {
+ for (CFG::const_iterator I = cfg->begin(), E = cfg->end(); I != E; ++I ) {
+ unsigned j = 1;
+ for (CFGBlock::const_iterator BI = (*I)->begin(), BEnd = (*I)->end() ;
+ BI != BEnd; ++BI, ++j ) {
+ if (const CFGStmt *SE = BI->getAs<CFGStmt>()) {
+ const Stmt *stmt= SE->getStmt();
+ std::pair<unsigned, unsigned> P((*I)->getBlockID(), j);
+ StmtMap[stmt] = P;
+
+ switch (stmt->getStmtClass()) {
+ case Stmt::DeclStmtClass:
+ DeclMap[cast<DeclStmt>(stmt)->getSingleDecl()] = P;
+ break;
+ case Stmt::IfStmtClass: {
+ const VarDecl *var = cast<IfStmt>(stmt)->getConditionVariable();
+ if (var)
+ DeclMap[var] = P;
+ break;
+ }
+ case Stmt::ForStmtClass: {
+ const VarDecl *var = cast<ForStmt>(stmt)->getConditionVariable();
+ if (var)
+ DeclMap[var] = P;
+ break;
+ }
+ case Stmt::WhileStmtClass: {
+ const VarDecl *var =
+ cast<WhileStmt>(stmt)->getConditionVariable();
+ if (var)
+ DeclMap[var] = P;
+ break;
+ }
+ case Stmt::SwitchStmtClass: {
+ const VarDecl *var =
+ cast<SwitchStmt>(stmt)->getConditionVariable();
+ if (var)
+ DeclMap[var] = P;
+ break;
+ }
+ case Stmt::CXXCatchStmtClass: {
+ const VarDecl *var =
+ cast<CXXCatchStmt>(stmt)->getExceptionDecl();
+ if (var)
+ DeclMap[var] = P;
+ break;
+ }
+ default:
+ break;
+ }
+ }
+ }
+ }
+ }
+
+
+ virtual ~StmtPrinterHelper() {}
+
+ const LangOptions &getLangOpts() const { return LangOpts; }
+ void setBlockID(signed i) { currentBlock = i; }
+ void setStmtID(unsigned i) { currentStmt = i; }
+
+ virtual bool handledStmt(Stmt *S, raw_ostream &OS) {
+ StmtMapTy::iterator I = StmtMap.find(S);
+
+ if (I == StmtMap.end())
+ return false;
+
+ if (currentBlock >= 0 && I->second.first == (unsigned) currentBlock
+ && I->second.second == currentStmt) {
+ return false;
+ }
+
+ OS << "[B" << I->second.first << "." << I->second.second << "]";
+ return true;
+ }
+
+ bool handleDecl(const Decl *D, raw_ostream &OS) {
+ DeclMapTy::iterator I = DeclMap.find(D);
+
+ if (I == DeclMap.end())
+ return false;
+
+ if (currentBlock >= 0 && I->second.first == (unsigned) currentBlock
+ && I->second.second == currentStmt) {
+ return false;
+ }
+
+ OS << "[B" << I->second.first << "." << I->second.second << "]";
+ return true;
+ }
+};
+} // end anonymous namespace
+
+
+namespace {
+class CFGBlockTerminatorPrint
+ : public StmtVisitor<CFGBlockTerminatorPrint,void> {
+
+ raw_ostream &OS;
+ StmtPrinterHelper* Helper;
+ PrintingPolicy Policy;
+public:
+ CFGBlockTerminatorPrint(raw_ostream &os, StmtPrinterHelper* helper,
+ const PrintingPolicy &Policy)
+ : OS(os), Helper(helper), Policy(Policy) {}
+
+ void VisitIfStmt(IfStmt *I) {
+ OS << "if ";
+ I->getCond()->printPretty(OS,Helper,Policy);
+ }
+
+ // Default case.
+ void VisitStmt(Stmt *Terminator) {
+ Terminator->printPretty(OS, Helper, Policy);
+ }
+
+ void VisitForStmt(ForStmt *F) {
+ OS << "for (" ;
+ if (F->getInit())
+ OS << "...";
+ OS << "; ";
+ if (Stmt *C = F->getCond())
+ C->printPretty(OS, Helper, Policy);
+ OS << "; ";
+ if (F->getInc())
+ OS << "...";
+ OS << ")";
+ }
+
+ void VisitWhileStmt(WhileStmt *W) {
+ OS << "while " ;
+ if (Stmt *C = W->getCond())
+ C->printPretty(OS, Helper, Policy);
+ }
+
+ void VisitDoStmt(DoStmt *D) {
+ OS << "do ... while ";
+ if (Stmt *C = D->getCond())
+ C->printPretty(OS, Helper, Policy);
+ }
+
+ void VisitSwitchStmt(SwitchStmt *Terminator) {
+ OS << "switch ";
+ Terminator->getCond()->printPretty(OS, Helper, Policy);
+ }
+
+ void VisitCXXTryStmt(CXXTryStmt *CS) {
+ OS << "try ...";
+ }
+
+ void VisitAbstractConditionalOperator(AbstractConditionalOperator* C) {
+ C->getCond()->printPretty(OS, Helper, Policy);
+ OS << " ? ... : ...";
+ }
+
+ void VisitChooseExpr(ChooseExpr *C) {
+ OS << "__builtin_choose_expr( ";
+ C->getCond()->printPretty(OS, Helper, Policy);
+ OS << " )";
+ }
+
+ void VisitIndirectGotoStmt(IndirectGotoStmt *I) {
+ OS << "goto *";
+ I->getTarget()->printPretty(OS, Helper, Policy);
+ }
+
+ void VisitBinaryOperator(BinaryOperator* B) {
+ if (!B->isLogicalOp()) {
+ VisitExpr(B);
+ return;
+ }
+
+ B->getLHS()->printPretty(OS, Helper, Policy);
+
+ switch (B->getOpcode()) {
+ case BO_LOr:
+ OS << " || ...";
+ return;
+ case BO_LAnd:
+ OS << " && ...";
+ return;
+ default:
+ llvm_unreachable("Invalid logical operator.");
+ }
+ }
+
+ void VisitExpr(Expr *E) {
+ E->printPretty(OS, Helper, Policy);
+ }
+};
+} // end anonymous namespace
+
+static void print_elem(raw_ostream &OS, StmtPrinterHelper* Helper,
+ const CFGElement &E) {
+ if (const CFGStmt *CS = E.getAs<CFGStmt>()) {
+ const Stmt *S = CS->getStmt();
+
+ if (Helper) {
+
+ // special printing for statement-expressions.
+ if (const StmtExpr *SE = dyn_cast<StmtExpr>(S)) {
+ const CompoundStmt *Sub = SE->getSubStmt();
+
+ if (Sub->children()) {
+ OS << "({ ... ; ";
+ Helper->handledStmt(*SE->getSubStmt()->body_rbegin(),OS);
+ OS << " })\n";
+ return;
+ }
+ }
+ // special printing for comma expressions.
+ if (const BinaryOperator* B = dyn_cast<BinaryOperator>(S)) {
+ if (B->getOpcode() == BO_Comma) {
+ OS << "... , ";
+ Helper->handledStmt(B->getRHS(),OS);
+ OS << '\n';
+ return;
+ }
+ }
+ }
+ S->printPretty(OS, Helper, PrintingPolicy(Helper->getLangOpts()));
+
+ if (isa<CXXOperatorCallExpr>(S)) {
+ OS << " (OperatorCall)";
+ }
+ else if (isa<CXXBindTemporaryExpr>(S)) {
+ OS << " (BindTemporary)";
+ }
+ else if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(S)) {
+ OS << " (CXXConstructExpr, " << CCE->getType().getAsString() << ")";
+ }
+ else if (const CastExpr *CE = dyn_cast<CastExpr>(S)) {
+ OS << " (" << CE->getStmtClassName() << ", "
+ << CE->getCastKindName()
+ << ", " << CE->getType().getAsString()
+ << ")";
+ }
+
+ // Expressions need a newline.
+ if (isa<Expr>(S))
+ OS << '\n';
+
+ } else if (const CFGInitializer *IE = E.getAs<CFGInitializer>()) {
+ const CXXCtorInitializer *I = IE->getInitializer();
+ if (I->isBaseInitializer())
+ OS << I->getBaseClass()->getAsCXXRecordDecl()->getName();
+ else OS << I->getAnyMember()->getName();
+
+ OS << "(";
+ if (Expr *IE = I->getInit())
+ IE->printPretty(OS, Helper, PrintingPolicy(Helper->getLangOpts()));
+ OS << ")";
+
+ if (I->isBaseInitializer())
+ OS << " (Base initializer)\n";
+ else OS << " (Member initializer)\n";
+
+ } else if (const CFGAutomaticObjDtor *DE = E.getAs<CFGAutomaticObjDtor>()){
+ const VarDecl *VD = DE->getVarDecl();
+ Helper->handleDecl(VD, OS);
+
+ const Type* T = VD->getType().getTypePtr();
+ if (const ReferenceType* RT = T->getAs<ReferenceType>())
+ T = RT->getPointeeType().getTypePtr();
+ else if (const Type *ET = T->getArrayElementTypeNoTypeQual())
+ T = ET;
+
+ OS << ".~" << T->getAsCXXRecordDecl()->getName().str() << "()";
+ OS << " (Implicit destructor)\n";
+
+ } else if (const CFGBaseDtor *BE = E.getAs<CFGBaseDtor>()) {
+ const CXXBaseSpecifier *BS = BE->getBaseSpecifier();
+ OS << "~" << BS->getType()->getAsCXXRecordDecl()->getName() << "()";
+ OS << " (Base object destructor)\n";
+
+ } else if (const CFGMemberDtor *ME = E.getAs<CFGMemberDtor>()) {
+ const FieldDecl *FD = ME->getFieldDecl();
+
+ const Type *T = FD->getType().getTypePtr();
+ if (const Type *ET = T->getArrayElementTypeNoTypeQual())
+ T = ET;
+
+ OS << "this->" << FD->getName();
+ OS << ".~" << T->getAsCXXRecordDecl()->getName() << "()";
+ OS << " (Member object destructor)\n";
+
+ } else if (const CFGTemporaryDtor *TE = E.getAs<CFGTemporaryDtor>()) {
+ const CXXBindTemporaryExpr *BT = TE->getBindTemporaryExpr();
+ OS << "~" << BT->getType()->getAsCXXRecordDecl()->getName() << "()";
+ OS << " (Temporary object destructor)\n";
+ }
+}
+
+static void print_block(raw_ostream &OS, const CFG* cfg,
+ const CFGBlock &B,
+ StmtPrinterHelper* Helper, bool print_edges,
+ bool ShowColors) {
+
+ if (Helper)
+ Helper->setBlockID(B.getBlockID());
+
+ // Print the header.
+ if (ShowColors)
+ OS.changeColor(raw_ostream::YELLOW, true);
+
+ OS << "\n [B" << B.getBlockID();
+
+ if (&B == &cfg->getEntry())
+ OS << " (ENTRY)]\n";
+ else if (&B == &cfg->getExit())
+ OS << " (EXIT)]\n";
+ else if (&B == cfg->getIndirectGotoBlock())
+ OS << " (INDIRECT GOTO DISPATCH)]\n";
+ else
+ OS << "]\n";
+
+ if (ShowColors)
+ OS.resetColor();
+
+ // Print the label of this block.
+ if (Stmt *Label = const_cast<Stmt*>(B.getLabel())) {
+
+ if (print_edges)
+ OS << " ";
+
+ if (LabelStmt *L = dyn_cast<LabelStmt>(Label))
+ OS << L->getName();
+ else if (CaseStmt *C = dyn_cast<CaseStmt>(Label)) {
+ OS << "case ";
+ C->getLHS()->printPretty(OS, Helper,
+ PrintingPolicy(Helper->getLangOpts()));
+ if (C->getRHS()) {
+ OS << " ... ";
+ C->getRHS()->printPretty(OS, Helper,
+ PrintingPolicy(Helper->getLangOpts()));
+ }
+ } else if (isa<DefaultStmt>(Label))
+ OS << "default";
+ else if (CXXCatchStmt *CS = dyn_cast<CXXCatchStmt>(Label)) {
+ OS << "catch (";
+ if (CS->getExceptionDecl())
+ CS->getExceptionDecl()->print(OS, PrintingPolicy(Helper->getLangOpts()),
+ 0);
+ else
+ OS << "...";
+ OS << ")";
+
+ } else
+ llvm_unreachable("Invalid label statement in CFGBlock.");
+
+ OS << ":\n";
+ }
+
+ // Iterate through the statements in the block and print them.
+ unsigned j = 1;
+
+ for (CFGBlock::const_iterator I = B.begin(), E = B.end() ;
+ I != E ; ++I, ++j ) {
+
+ // Print the statement # in the basic block and the statement itself.
+ if (print_edges)
+ OS << " ";
+
+ OS << llvm::format("%3d", j) << ": ";
+
+ if (Helper)
+ Helper->setStmtID(j);
+
+ print_elem(OS, Helper, *I);
+ }
+
+ // Print the terminator of this block.
+ if (B.getTerminator()) {
+ if (ShowColors)
+ OS.changeColor(raw_ostream::GREEN);
+
+ OS << " T: ";
+
+ if (Helper) Helper->setBlockID(-1);
+
+ CFGBlockTerminatorPrint TPrinter(OS, Helper,
+ PrintingPolicy(Helper->getLangOpts()));
+ TPrinter.Visit(const_cast<Stmt*>(B.getTerminator().getStmt()));
+ OS << '\n';
+
+ if (ShowColors)
+ OS.resetColor();
+ }
+
+ if (print_edges) {
+ // Print the predecessors of this block.
+ if (!B.pred_empty()) {
+ const raw_ostream::Colors Color = raw_ostream::BLUE;
+ if (ShowColors)
+ OS.changeColor(Color);
+ OS << " Preds " ;
+ if (ShowColors)
+ OS.resetColor();
+ OS << '(' << B.pred_size() << "):";
+ unsigned i = 0;
+
+ if (ShowColors)
+ OS.changeColor(Color);
+
+ for (CFGBlock::const_pred_iterator I = B.pred_begin(), E = B.pred_end();
+ I != E; ++I, ++i) {
+
+ if (i == 8 || (i-8) == 0)
+ OS << "\n ";
+
+ OS << " B" << (*I)->getBlockID();
+ }
+
+ if (ShowColors)
+ OS.resetColor();
+
+ OS << '\n';
+ }
+
+ // Print the successors of this block.
+ if (!B.succ_empty()) {
+ const raw_ostream::Colors Color = raw_ostream::MAGENTA;
+ if (ShowColors)
+ OS.changeColor(Color);
+ OS << " Succs ";
+ if (ShowColors)
+ OS.resetColor();
+ OS << '(' << B.succ_size() << "):";
+ unsigned i = 0;
+
+ if (ShowColors)
+ OS.changeColor(Color);
+
+ for (CFGBlock::const_succ_iterator I = B.succ_begin(), E = B.succ_end();
+ I != E; ++I, ++i) {
+
+ if (i == 8 || (i-8) % 10 == 0)
+ OS << "\n ";
+
+ if (*I)
+ OS << " B" << (*I)->getBlockID();
+ else
+ OS << " NULL";
+ }
+
+ if (ShowColors)
+ OS.resetColor();
+ OS << '\n';
+ }
+ }
+}
+
+
+/// dump - A simple pretty printer of a CFG that outputs to stderr.
+void CFG::dump(const LangOptions &LO, bool ShowColors) const {
+ print(llvm::errs(), LO, ShowColors);
+}
+
+/// print - A simple pretty printer of a CFG that outputs to an ostream.
+void CFG::print(raw_ostream &OS, const LangOptions &LO, bool ShowColors) const {
+ StmtPrinterHelper Helper(this, LO);
+
+ // Print the entry block.
+ print_block(OS, this, getEntry(), &Helper, true, ShowColors);
+
+ // Iterate through the CFGBlocks and print them one by one.
+ for (const_iterator I = Blocks.begin(), E = Blocks.end() ; I != E ; ++I) {
+ // Skip the entry block, because we already printed it.
+ if (&(**I) == &getEntry() || &(**I) == &getExit())
+ continue;
+
+ print_block(OS, this, **I, &Helper, true, ShowColors);
+ }
+
+ // Print the exit block.
+ print_block(OS, this, getExit(), &Helper, true, ShowColors);
+ OS << '\n';
+ OS.flush();
+}
+
+/// dump - A simply pretty printer of a CFGBlock that outputs to stderr.
+void CFGBlock::dump(const CFG* cfg, const LangOptions &LO,
+ bool ShowColors) const {
+ print(llvm::errs(), cfg, LO, ShowColors);
+}
+
+/// print - A simple pretty printer of a CFGBlock that outputs to an ostream.
+/// Generally this will only be called from CFG::print.
+void CFGBlock::print(raw_ostream &OS, const CFG* cfg,
+ const LangOptions &LO, bool ShowColors) const {
+ StmtPrinterHelper Helper(cfg, LO);
+ print_block(OS, cfg, *this, &Helper, true, ShowColors);
+ OS << '\n';
+}
+
+/// printTerminator - A simple pretty printer of the terminator of a CFGBlock.
+void CFGBlock::printTerminator(raw_ostream &OS,
+ const LangOptions &LO) const {
+ CFGBlockTerminatorPrint TPrinter(OS, NULL, PrintingPolicy(LO));
+ TPrinter.Visit(const_cast<Stmt*>(getTerminator().getStmt()));
+}
+
+Stmt *CFGBlock::getTerminatorCondition() {
+ Stmt *Terminator = this->Terminator;
+ if (!Terminator)
+ return NULL;
+
+ Expr *E = NULL;
+
+ switch (Terminator->getStmtClass()) {
+ default:
+ break;
+
+ case Stmt::ForStmtClass:
+ E = cast<ForStmt>(Terminator)->getCond();
+ break;
+
+ case Stmt::WhileStmtClass:
+ E = cast<WhileStmt>(Terminator)->getCond();
+ break;
+
+ case Stmt::DoStmtClass:
+ E = cast<DoStmt>(Terminator)->getCond();
+ break;
+
+ case Stmt::IfStmtClass:
+ E = cast<IfStmt>(Terminator)->getCond();
+ break;
+
+ case Stmt::ChooseExprClass:
+ E = cast<ChooseExpr>(Terminator)->getCond();
+ break;
+
+ case Stmt::IndirectGotoStmtClass:
+ E = cast<IndirectGotoStmt>(Terminator)->getTarget();
+ break;
+
+ case Stmt::SwitchStmtClass:
+ E = cast<SwitchStmt>(Terminator)->getCond();
+ break;
+
+ case Stmt::BinaryConditionalOperatorClass:
+ E = cast<BinaryConditionalOperator>(Terminator)->getCond();
+ break;
+
+ case Stmt::ConditionalOperatorClass:
+ E = cast<ConditionalOperator>(Terminator)->getCond();
+ break;
+
+ case Stmt::BinaryOperatorClass: // '&&' and '||'
+ E = cast<BinaryOperator>(Terminator)->getLHS();
+ break;
+
+ case Stmt::ObjCForCollectionStmtClass:
+ return Terminator;
+ }
+
+ return E ? E->IgnoreParens() : NULL;
+}
+
+//===----------------------------------------------------------------------===//
+// CFG Graphviz Visualization
+//===----------------------------------------------------------------------===//
+
+
+#ifndef NDEBUG
+static StmtPrinterHelper* GraphHelper;
+#endif
+
+void CFG::viewCFG(const LangOptions &LO) const {
+#ifndef NDEBUG
+ StmtPrinterHelper H(this, LO);
+ GraphHelper = &H;
+ llvm::ViewGraph(this,"CFG");
+ GraphHelper = NULL;
+#endif
+}
+
+namespace llvm {
+template<>
+struct DOTGraphTraits<const CFG*> : public DefaultDOTGraphTraits {
+
+ DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
+
+ static std::string getNodeLabel(const CFGBlock *Node, const CFG* Graph) {
+
+#ifndef NDEBUG
+ std::string OutSStr;
+ llvm::raw_string_ostream Out(OutSStr);
+ print_block(Out,Graph, *Node, GraphHelper, false, false);
+ std::string& OutStr = Out.str();
+
+ if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
+
+ // Process string output to make it nicer...
+ for (unsigned i = 0; i != OutStr.length(); ++i)
+ if (OutStr[i] == '\n') { // Left justify
+ OutStr[i] = '\\';
+ OutStr.insert(OutStr.begin()+i+1, 'l');
+ }
+
+ return OutStr;
+#else
+ return "";
+#endif
+ }
+};
+} // end namespace llvm