зеркало из https://github.com/microsoft/clang-1.git
3392 строки
107 KiB
C++
3392 строки
107 KiB
C++
//===--- CFG.cpp - Classes for representing and building CFGs----*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines the CFG and CFGBuilder classes for representing and
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// building Control-Flow Graphs (CFGs) from ASTs.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/Analysis/Support/SaveAndRestore.h"
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#include "clang/Analysis/CFG.h"
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#include "clang/AST/DeclCXX.h"
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#include "clang/AST/StmtVisitor.h"
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#include "clang/AST/PrettyPrinter.h"
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#include "llvm/Support/GraphWriter.h"
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#include "llvm/Support/Allocator.h"
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#include "llvm/Support/Format.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/OwningPtr.h"
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using namespace clang;
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namespace {
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static SourceLocation GetEndLoc(Decl* D) {
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if (VarDecl* VD = dyn_cast<VarDecl>(D))
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if (Expr* Ex = VD->getInit())
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return Ex->getSourceRange().getEnd();
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return D->getLocation();
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}
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class AddStmtChoice {
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public:
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enum Kind { NotAlwaysAdd = 0,
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AlwaysAdd = 1,
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AsLValueNotAlwaysAdd = 2,
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AlwaysAddAsLValue = 3 };
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AddStmtChoice(Kind kind) : k(kind) {}
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bool alwaysAdd() const { return (unsigned)k & 0x1; }
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bool asLValue() const { return k >= AsLValueNotAlwaysAdd; }
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private:
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Kind k;
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};
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/// LocalScope - Node in tree of local scopes created for C++ implicit
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/// destructor calls generation. It contains list of automatic variables
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/// declared in the scope and link to position in previous scope this scope
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/// began in.
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///
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/// The process of creating local scopes is as follows:
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/// - Init CFGBuilder::ScopePos with invalid position (equivalent for null),
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/// - Before processing statements in scope (e.g. CompoundStmt) create
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/// LocalScope object using CFGBuilder::ScopePos as link to previous scope
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/// and set CFGBuilder::ScopePos to the end of new scope,
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/// - On every occurrence of VarDecl increase CFGBuilder::ScopePos if it points
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/// at this VarDecl,
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/// - For every normal (without jump) end of scope add to CFGBlock destructors
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/// for objects in the current scope,
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/// - For every jump add to CFGBlock destructors for objects
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/// between CFGBuilder::ScopePos and local scope position saved for jump
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/// target. Thanks to C++ restrictions on goto jumps we can be sure that
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/// jump target position will be on the path to root from CFGBuilder::ScopePos
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/// (adding any variable that doesn't need constructor to be called to
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/// LocalScope can break this assumption),
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///
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class LocalScope {
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public:
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typedef llvm::SmallVector<VarDecl*, 4> AutomaticVarsTy;
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/// const_iterator - Iterates local scope backwards and jumps to previous
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/// scope on reaching the beginning of currently iterated scope.
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class const_iterator {
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const LocalScope* Scope;
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/// VarIter is guaranteed to be greater then 0 for every valid iterator.
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/// Invalid iterator (with null Scope) has VarIter equal to 0.
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unsigned VarIter;
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public:
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/// Create invalid iterator. Dereferencing invalid iterator is not allowed.
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/// Incrementing invalid iterator is allowed and will result in invalid
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/// iterator.
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const_iterator()
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: Scope(NULL), VarIter(0) {}
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/// Create valid iterator. In case when S.Prev is an invalid iterator and
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/// I is equal to 0, this will create invalid iterator.
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const_iterator(const LocalScope& S, unsigned I)
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: Scope(&S), VarIter(I) {
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// Iterator to "end" of scope is not allowed. Handle it by going up
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// in scopes tree possibly up to invalid iterator in the root.
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if (VarIter == 0 && Scope)
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*this = Scope->Prev;
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}
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VarDecl* const* operator->() const {
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assert (Scope && "Dereferencing invalid iterator is not allowed");
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assert (VarIter != 0 && "Iterator has invalid value of VarIter member");
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return &Scope->Vars[VarIter - 1];
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}
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VarDecl* operator*() const {
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return *this->operator->();
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}
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const_iterator& operator++() {
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if (!Scope)
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return *this;
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assert (VarIter != 0 && "Iterator has invalid value of VarIter member");
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--VarIter;
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if (VarIter == 0)
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*this = Scope->Prev;
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return *this;
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}
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const_iterator operator++(int) {
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const_iterator P = *this;
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++*this;
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return P;
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}
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bool operator==(const const_iterator& rhs) const {
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return Scope == rhs.Scope && VarIter == rhs.VarIter;
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}
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bool operator!=(const const_iterator& rhs) const {
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return !(*this == rhs);
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}
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operator bool() const {
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return *this != const_iterator();
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}
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int distance(const_iterator L);
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};
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friend class const_iterator;
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private:
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/// Automatic variables in order of declaration.
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AutomaticVarsTy Vars;
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/// Iterator to variable in previous scope that was declared just before
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/// begin of this scope.
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const_iterator Prev;
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public:
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/// Constructs empty scope linked to previous scope in specified place.
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LocalScope(const_iterator P)
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: Vars()
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, Prev(P) {}
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/// Begin of scope in direction of CFG building (backwards).
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const_iterator begin() const { return const_iterator(*this, Vars.size()); }
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void addVar(VarDecl* VD) {
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Vars.push_back(VD);
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}
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};
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/// distance - Calculates distance from this to L. L must be reachable from this
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/// (with use of ++ operator). Cost of calculating the distance is linear w.r.t.
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/// number of scopes between this and L.
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int LocalScope::const_iterator::distance(LocalScope::const_iterator L) {
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int D = 0;
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const_iterator F = *this;
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while (F.Scope != L.Scope) {
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assert (F != const_iterator()
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&& "L iterator is not reachable from F iterator.");
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D += F.VarIter;
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F = F.Scope->Prev;
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}
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D += F.VarIter - L.VarIter;
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return D;
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}
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/// BlockScopePosPair - Structure for specifying position in CFG during its
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/// build process. It consists of CFGBlock that specifies position in CFG graph
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/// and LocalScope::const_iterator that specifies position in LocalScope graph.
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struct BlockScopePosPair {
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BlockScopePosPair() {}
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BlockScopePosPair(CFGBlock* B, LocalScope::const_iterator S)
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: Block(B), ScopePos(S) {}
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CFGBlock* Block;
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LocalScope::const_iterator ScopePos;
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};
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/// CFGBuilder - This class implements CFG construction from an AST.
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/// The builder is stateful: an instance of the builder should be used to only
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/// construct a single CFG.
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///
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/// Example usage:
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///
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/// CFGBuilder builder;
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/// CFG* cfg = builder.BuildAST(stmt1);
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///
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/// CFG construction is done via a recursive walk of an AST. We actually parse
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/// the AST in reverse order so that the successor of a basic block is
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/// constructed prior to its predecessor. This allows us to nicely capture
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/// implicit fall-throughs without extra basic blocks.
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///
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class CFGBuilder {
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typedef BlockScopePosPair JumpTarget;
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typedef BlockScopePosPair JumpSource;
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ASTContext *Context;
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llvm::OwningPtr<CFG> cfg;
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CFGBlock* Block;
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CFGBlock* Succ;
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JumpTarget ContinueJumpTarget;
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JumpTarget BreakJumpTarget;
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CFGBlock* SwitchTerminatedBlock;
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CFGBlock* DefaultCaseBlock;
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CFGBlock* TryTerminatedBlock;
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// Current position in local scope.
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LocalScope::const_iterator ScopePos;
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// LabelMap records the mapping from Label expressions to their jump targets.
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typedef llvm::DenseMap<LabelStmt*, JumpTarget> LabelMapTy;
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LabelMapTy LabelMap;
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// A list of blocks that end with a "goto" that must be backpatched to their
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// resolved targets upon completion of CFG construction.
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typedef std::vector<JumpSource> BackpatchBlocksTy;
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BackpatchBlocksTy BackpatchBlocks;
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// A list of labels whose address has been taken (for indirect gotos).
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typedef llvm::SmallPtrSet<LabelStmt*,5> LabelSetTy;
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LabelSetTy AddressTakenLabels;
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bool badCFG;
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CFG::BuildOptions BuildOpts;
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public:
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explicit CFGBuilder() : cfg(new CFG()), // crew a new CFG
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Block(NULL), Succ(NULL),
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SwitchTerminatedBlock(NULL), DefaultCaseBlock(NULL),
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TryTerminatedBlock(NULL), badCFG(false) {}
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// buildCFG - Used by external clients to construct the CFG.
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CFG* buildCFG(const Decl *D, Stmt *Statement, ASTContext *C,
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CFG::BuildOptions BO);
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private:
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// Visitors to walk an AST and construct the CFG.
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CFGBlock *VisitAddrLabelExpr(AddrLabelExpr *A, AddStmtChoice asc);
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CFGBlock *VisitBinaryOperator(BinaryOperator *B, AddStmtChoice asc);
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CFGBlock *VisitBlockExpr(BlockExpr* E, AddStmtChoice asc);
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CFGBlock *VisitBreakStmt(BreakStmt *B);
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CFGBlock *VisitCXXCatchStmt(CXXCatchStmt *S);
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CFGBlock *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E,
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AddStmtChoice asc);
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CFGBlock *VisitCXXThrowExpr(CXXThrowExpr *T);
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CFGBlock *VisitCXXTryStmt(CXXTryStmt *S);
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CFGBlock *VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E,
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AddStmtChoice asc);
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CFGBlock *VisitCXXConstructExpr(CXXConstructExpr *C, AddStmtChoice asc);
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CFGBlock *VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E,
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AddStmtChoice asc);
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CFGBlock *VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *C,
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AddStmtChoice asc);
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CFGBlock *VisitCXXMemberCallExpr(CXXMemberCallExpr *C, AddStmtChoice asc);
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CFGBlock *VisitCallExpr(CallExpr *C, AddStmtChoice asc);
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CFGBlock *VisitCaseStmt(CaseStmt *C);
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CFGBlock *VisitChooseExpr(ChooseExpr *C, AddStmtChoice asc);
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CFGBlock *VisitCompoundStmt(CompoundStmt *C);
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CFGBlock *VisitConditionalOperator(ConditionalOperator *C, AddStmtChoice asc);
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CFGBlock *VisitContinueStmt(ContinueStmt *C);
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CFGBlock *VisitDeclStmt(DeclStmt *DS);
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CFGBlock *VisitDeclSubExpr(DeclStmt* DS);
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CFGBlock *VisitDefaultStmt(DefaultStmt *D);
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CFGBlock *VisitDoStmt(DoStmt *D);
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CFGBlock *VisitForStmt(ForStmt *F);
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CFGBlock *VisitGotoStmt(GotoStmt* G);
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CFGBlock *VisitIfStmt(IfStmt *I);
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CFGBlock *VisitImplicitCastExpr(ImplicitCastExpr *E, AddStmtChoice asc);
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CFGBlock *VisitIndirectGotoStmt(IndirectGotoStmt *I);
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CFGBlock *VisitLabelStmt(LabelStmt *L);
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CFGBlock *VisitMemberExpr(MemberExpr *M, AddStmtChoice asc);
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CFGBlock *VisitObjCAtCatchStmt(ObjCAtCatchStmt *S);
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CFGBlock *VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S);
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CFGBlock *VisitObjCAtThrowStmt(ObjCAtThrowStmt *S);
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CFGBlock *VisitObjCAtTryStmt(ObjCAtTryStmt *S);
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CFGBlock *VisitObjCForCollectionStmt(ObjCForCollectionStmt *S);
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CFGBlock *VisitReturnStmt(ReturnStmt* R);
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CFGBlock *VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E, AddStmtChoice asc);
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CFGBlock *VisitStmtExpr(StmtExpr *S, AddStmtChoice asc);
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CFGBlock *VisitSwitchStmt(SwitchStmt *S);
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CFGBlock *VisitWhileStmt(WhileStmt *W);
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CFGBlock *Visit(Stmt *S, AddStmtChoice asc = AddStmtChoice::NotAlwaysAdd);
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CFGBlock *VisitStmt(Stmt *S, AddStmtChoice asc);
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CFGBlock *VisitChildren(Stmt* S);
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// Visitors to walk an AST and generate destructors of temporaries in
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// full expression.
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CFGBlock *VisitForTemporaryDtors(Stmt *E, bool BindToTemporary = false);
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CFGBlock *VisitChildrenForTemporaryDtors(Stmt *E);
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CFGBlock *VisitBinaryOperatorForTemporaryDtors(BinaryOperator *E);
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CFGBlock *VisitCXXBindTemporaryExprForTemporaryDtors(CXXBindTemporaryExpr *E,
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bool BindToTemporary);
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CFGBlock *VisitConditionalOperatorForTemporaryDtors(ConditionalOperator *E,
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bool BindToTemporary);
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// NYS == Not Yet Supported
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CFGBlock* NYS() {
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badCFG = true;
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return Block;
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}
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void autoCreateBlock() { if (!Block) Block = createBlock(); }
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CFGBlock *createBlock(bool add_successor = true);
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CFGBlock *addStmt(Stmt *S) {
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return Visit(S, AddStmtChoice::AlwaysAdd);
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}
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CFGBlock *addInitializer(CXXBaseOrMemberInitializer *I);
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void addAutomaticObjDtors(LocalScope::const_iterator B,
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LocalScope::const_iterator E, Stmt* S);
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void addImplicitDtorsForDestructor(const CXXDestructorDecl *DD);
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// Local scopes creation.
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LocalScope* createOrReuseLocalScope(LocalScope* Scope);
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void addLocalScopeForStmt(Stmt* S);
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LocalScope* addLocalScopeForDeclStmt(DeclStmt* DS, LocalScope* Scope = NULL);
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LocalScope* addLocalScopeForVarDecl(VarDecl* VD, LocalScope* Scope = NULL);
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void addLocalScopeAndDtors(Stmt* S);
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// Interface to CFGBlock - adding CFGElements.
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void AppendStmt(CFGBlock *B, Stmt *S,
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AddStmtChoice asc = AddStmtChoice::AlwaysAdd) {
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B->appendStmt(S, cfg->getBumpVectorContext(), asc.asLValue());
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}
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void appendInitializer(CFGBlock *B, CXXBaseOrMemberInitializer *I) {
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B->appendInitializer(I, cfg->getBumpVectorContext());
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}
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void appendBaseDtor(CFGBlock *B, const CXXBaseSpecifier *BS) {
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B->appendBaseDtor(BS, cfg->getBumpVectorContext());
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}
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void appendMemberDtor(CFGBlock *B, FieldDecl *FD) {
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B->appendMemberDtor(FD, cfg->getBumpVectorContext());
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}
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void appendTemporaryDtor(CFGBlock *B, CXXBindTemporaryExpr *E) {
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B->appendTemporaryDtor(E, cfg->getBumpVectorContext());
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}
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void insertAutomaticObjDtors(CFGBlock* Blk, CFGBlock::iterator I,
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LocalScope::const_iterator B, LocalScope::const_iterator E, Stmt* S);
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void appendAutomaticObjDtors(CFGBlock* Blk, LocalScope::const_iterator B,
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LocalScope::const_iterator E, Stmt* S);
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void prependAutomaticObjDtorsWithTerminator(CFGBlock* Blk,
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LocalScope::const_iterator B, LocalScope::const_iterator E);
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void AddSuccessor(CFGBlock *B, CFGBlock *S) {
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B->addSuccessor(S, cfg->getBumpVectorContext());
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}
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/// TryResult - a class representing a variant over the values
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/// 'true', 'false', or 'unknown'. This is returned by TryEvaluateBool,
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/// and is used by the CFGBuilder to decide if a branch condition
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/// can be decided up front during CFG construction.
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class TryResult {
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int X;
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public:
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TryResult(bool b) : X(b ? 1 : 0) {}
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TryResult() : X(-1) {}
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bool isTrue() const { return X == 1; }
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bool isFalse() const { return X == 0; }
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bool isKnown() const { return X >= 0; }
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void negate() {
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assert(isKnown());
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X ^= 0x1;
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}
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};
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/// TryEvaluateBool - Try and evaluate the Stmt and return 0 or 1
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/// if we can evaluate to a known value, otherwise return -1.
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TryResult TryEvaluateBool(Expr *S) {
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if (!BuildOpts.PruneTriviallyFalseEdges)
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return TryResult();
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Expr::EvalResult Result;
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if (!S->isTypeDependent() && !S->isValueDependent() &&
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S->Evaluate(Result, *Context) && Result.Val.isInt())
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return Result.Val.getInt().getBoolValue();
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return TryResult();
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}
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};
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// FIXME: Add support for dependent-sized array types in C++?
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// Does it even make sense to build a CFG for an uninstantiated template?
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static VariableArrayType* FindVA(Type* t) {
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while (ArrayType* vt = dyn_cast<ArrayType>(t)) {
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if (VariableArrayType* vat = dyn_cast<VariableArrayType>(vt))
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if (vat->getSizeExpr())
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return vat;
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t = vt->getElementType().getTypePtr();
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}
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return 0;
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}
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/// BuildCFG - Constructs a CFG from an AST (a Stmt*). The AST can represent an
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/// arbitrary statement. Examples include a single expression or a function
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/// body (compound statement). The ownership of the returned CFG is
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/// transferred to the caller. If CFG construction fails, this method returns
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/// NULL.
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CFG* CFGBuilder::buildCFG(const Decl *D, Stmt* Statement, ASTContext* C,
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CFG::BuildOptions BO) {
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Context = C;
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assert(cfg.get());
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if (!Statement)
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return NULL;
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BuildOpts = BO;
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// Create an empty block that will serve as the exit block for the CFG. Since
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// this is the first block added to the CFG, it will be implicitly registered
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// as the exit block.
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Succ = createBlock();
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assert(Succ == &cfg->getExit());
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Block = NULL; // the EXIT block is empty. Create all other blocks lazily.
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if (BuildOpts.AddImplicitDtors)
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if (const CXXDestructorDecl *DD = dyn_cast_or_null<CXXDestructorDecl>(D))
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addImplicitDtorsForDestructor(DD);
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// Visit the statements and create the CFG.
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CFGBlock *B = addStmt(Statement);
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if (badCFG)
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return NULL;
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// For C++ constructor add initializers to CFG.
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if (const CXXConstructorDecl *CD = dyn_cast_or_null<CXXConstructorDecl>(D)) {
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for (CXXConstructorDecl::init_const_reverse_iterator I = CD->init_rbegin(),
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E = CD->init_rend(); I != E; ++I) {
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B = addInitializer(*I);
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if (badCFG)
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return NULL;
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}
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}
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if (B)
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Succ = B;
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// Backpatch the gotos whose label -> block mappings we didn't know when we
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// encountered them.
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for (BackpatchBlocksTy::iterator I = BackpatchBlocks.begin(),
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E = BackpatchBlocks.end(); I != E; ++I ) {
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CFGBlock* B = I->Block;
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GotoStmt* G = cast<GotoStmt>(B->getTerminator());
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LabelMapTy::iterator LI = LabelMap.find(G->getLabel());
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|
// 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->ScopePos, JT.ScopePos);
|
|
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;
|
|
}
|
|
|
|
/// addInitializer - Add C++ base or member initializer element to CFG.
|
|
CFGBlock *CFGBuilder::addInitializer(CXXBaseOrMemberInitializer *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->getMember())
|
|
IsReference = FD->getType()->isReferenceType();
|
|
HasTemporaries = isa<CXXExprWithTemporaries>(Init);
|
|
|
|
if (BuildOpts.AddImplicitDtors && HasTemporaries) {
|
|
// Generate destructors for temporaries in initialization expression.
|
|
VisitForTemporaryDtors(cast<CXXExprWithTemporaries>(Init)->getSubExpr(),
|
|
IsReference);
|
|
}
|
|
}
|
|
|
|
autoCreateBlock();
|
|
appendInitializer(Block, I);
|
|
|
|
if (Init) {
|
|
AddStmtChoice asc = IsReference
|
|
? AddStmtChoice::AsLValueNotAlwaysAdd
|
|
: AddStmtChoice::NotAlwaysAdd;
|
|
if (HasTemporaries)
|
|
// For expression with temporaries go directly to subexpression to omit
|
|
// generating destructors for the second time.
|
|
return Visit(cast<CXXExprWithTemporaries>(Init)->getSubExpr(), asc);
|
|
return Visit(Init, asc);
|
|
}
|
|
|
|
return Block;
|
|
}
|
|
|
|
/// 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;
|
|
|
|
autoCreateBlock();
|
|
appendAutomaticObjDtors(Block, B, E, 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) {
|
|
Scope = cfg->getAllocator().Allocate<LocalScope>();
|
|
new (Scope) LocalScope(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;
|
|
if (LabelStmt* LS = dyn_cast<LabelStmt>(SI))
|
|
SI = LS->getSubStmt();
|
|
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 (LabelStmt* LS = dyn_cast<LabelStmt>(S))
|
|
S = LS->getSubStmt();
|
|
if (DeclStmt* DS = dyn_cast<DeclStmt>(S))
|
|
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 (const ReferenceType* RT = QT.getTypePtr()->getAs<ReferenceType>()) {
|
|
QT = RT->getPointeeType();
|
|
if (!QT.isConstQualified())
|
|
return Scope;
|
|
if (!VD->getInit() || !VD->getInit()->Classify(*Context).isRValue())
|
|
return Scope;
|
|
}
|
|
|
|
// Check for constant size array. Set type to array element type.
|
|
if (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);
|
|
}
|
|
|
|
/// insertAutomaticObjDtors - Insert destructor CFGElements for variables with
|
|
/// automatic storage duration to CFGBlock's elements vector. Insertion will be
|
|
/// performed in place specified with iterator.
|
|
void CFGBuilder::insertAutomaticObjDtors(CFGBlock* Blk, CFGBlock::iterator I,
|
|
LocalScope::const_iterator B, LocalScope::const_iterator E, Stmt* S) {
|
|
BumpVectorContext& C = cfg->getBumpVectorContext();
|
|
I = Blk->beginAutomaticObjDtorsInsert(I, B.distance(E), C);
|
|
while (B != E)
|
|
I = Blk->insertAutomaticObjDtor(I, *B++, S);
|
|
}
|
|
|
|
/// appendAutomaticObjDtors - Append destructor CFGElements for variables with
|
|
/// automatic storage duration to CFGBlock's elements vector. Elements will be
|
|
/// appended to physical end of the vector which happens to be logical
|
|
/// beginning.
|
|
void CFGBuilder::appendAutomaticObjDtors(CFGBlock* Blk,
|
|
LocalScope::const_iterator B, LocalScope::const_iterator E, Stmt* S) {
|
|
insertAutomaticObjDtors(Blk, Blk->begin(), B, E, 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.
|
|
void CFGBuilder::prependAutomaticObjDtorsWithTerminator(CFGBlock* Blk,
|
|
LocalScope::const_iterator B, LocalScope::const_iterator E) {
|
|
insertAutomaticObjDtors(Blk, Blk->end(), B, E, 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) {
|
|
tryAgain:
|
|
if (!S) {
|
|
badCFG = true;
|
|
return 0;
|
|
}
|
|
switch (S->getStmtClass()) {
|
|
default:
|
|
return VisitStmt(S, asc);
|
|
|
|
case Stmt::AddrLabelExprClass:
|
|
return VisitAddrLabelExpr(cast<AddrLabelExpr>(S), asc);
|
|
|
|
case Stmt::BinaryOperatorClass:
|
|
return VisitBinaryOperator(cast<BinaryOperator>(S), asc);
|
|
|
|
case Stmt::BlockExprClass:
|
|
return VisitBlockExpr(cast<BlockExpr>(S), asc);
|
|
|
|
case Stmt::BreakStmtClass:
|
|
return VisitBreakStmt(cast<BreakStmt>(S));
|
|
|
|
case Stmt::CallExprClass:
|
|
case Stmt::CXXOperatorCallExprClass:
|
|
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::CXXExprWithTemporariesClass:
|
|
return VisitCXXExprWithTemporaries(cast<CXXExprWithTemporaries>(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::CXXMemberCallExprClass:
|
|
return VisitCXXMemberCallExpr(cast<CXXMemberCallExpr>(S), asc);
|
|
|
|
case Stmt::CXXThrowExprClass:
|
|
return VisitCXXThrowExpr(cast<CXXThrowExpr>(S));
|
|
|
|
case Stmt::CXXTryStmtClass:
|
|
return VisitCXXTryStmt(cast<CXXTryStmt>(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::MemberExprClass:
|
|
return VisitMemberExpr(cast<MemberExpr>(S), asc);
|
|
|
|
case Stmt::ObjCAtCatchStmtClass:
|
|
return VisitObjCAtCatchStmt(cast<ObjCAtCatchStmt>(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::ParenExprClass:
|
|
S = cast<ParenExpr>(S)->getSubExpr();
|
|
goto tryAgain;
|
|
|
|
case Stmt::NullStmtClass:
|
|
return Block;
|
|
|
|
case Stmt::ReturnStmtClass:
|
|
return VisitReturnStmt(cast<ReturnStmt>(S));
|
|
|
|
case Stmt::SizeOfAlignOfExprClass:
|
|
return VisitSizeOfAlignOfExpr(cast<SizeOfAlignOfExpr>(S), asc);
|
|
|
|
case Stmt::StmtExprClass:
|
|
return VisitStmtExpr(cast<StmtExpr>(S), asc);
|
|
|
|
case Stmt::SwitchStmtClass:
|
|
return VisitSwitchStmt(cast<SwitchStmt>(S));
|
|
|
|
case Stmt::WhileStmtClass:
|
|
return VisitWhileStmt(cast<WhileStmt>(S));
|
|
}
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitStmt(Stmt *S, AddStmtChoice asc) {
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, S, asc);
|
|
}
|
|
|
|
return VisitChildren(S);
|
|
}
|
|
|
|
/// VisitChildren - Visit the children of a Stmt.
|
|
CFGBlock *CFGBuilder::VisitChildren(Stmt* Terminator) {
|
|
CFGBlock *B = Block;
|
|
for (Stmt::child_iterator I = Terminator->child_begin(),
|
|
E = Terminator->child_end(); I != E; ++I) {
|
|
if (*I) B = Visit(*I);
|
|
}
|
|
return B;
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitAddrLabelExpr(AddrLabelExpr *A,
|
|
AddStmtChoice asc) {
|
|
AddressTakenLabels.insert(A->getLabel());
|
|
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, A, asc);
|
|
}
|
|
|
|
return Block;
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitBinaryOperator(BinaryOperator *B,
|
|
AddStmtChoice asc) {
|
|
if (B->isLogicalOp()) { // && or ||
|
|
CFGBlock* ConfluenceBlock = Block ? Block : createBlock();
|
|
AppendStmt(ConfluenceBlock, B, asc);
|
|
|
|
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();
|
|
}
|
|
|
|
// 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);
|
|
}
|
|
|
|
// Generate the blocks for evaluating the LHS.
|
|
Block = LHSBlock;
|
|
return addStmt(B->getLHS());
|
|
}
|
|
else if (B->getOpcode() == BO_Comma) { // ,
|
|
autoCreateBlock();
|
|
AppendStmt(Block, B, asc);
|
|
addStmt(B->getRHS());
|
|
return addStmt(B->getLHS());
|
|
}
|
|
else if (B->isAssignmentOp()) {
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, B, asc);
|
|
}
|
|
|
|
Visit(B->getLHS(), AddStmtChoice::AsLValueNotAlwaysAdd);
|
|
return Visit(B->getRHS());
|
|
}
|
|
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, B, asc);
|
|
}
|
|
|
|
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::VisitBlockExpr(BlockExpr *E, AddStmtChoice asc) {
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, E, asc);
|
|
}
|
|
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.ScopePos, B);
|
|
AddSuccessor(Block, BreakJumpTarget.Block);
|
|
} else
|
|
badCFG = true;
|
|
|
|
|
|
return Block;
|
|
}
|
|
|
|
static bool CanThrow(Expr *E) {
|
|
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->hasEmptyExceptionSpec())
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitCallExpr(CallExpr *C, AddStmtChoice asc) {
|
|
// If this is a call to a no-return function, this stops the block here.
|
|
bool NoReturn = false;
|
|
if (getFunctionExtInfo(*C->getCallee()->getType()).getNoReturn()) {
|
|
NoReturn = true;
|
|
}
|
|
|
|
bool AddEHEdge = false;
|
|
|
|
// Languages without exceptions are assumed to not throw.
|
|
if (Context->getLangOptions().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()))
|
|
AddEHEdge = false;
|
|
|
|
if (!NoReturn && !AddEHEdge) {
|
|
if (asc.asLValue())
|
|
return VisitStmt(C, AddStmtChoice::AlwaysAddAsLValue);
|
|
else
|
|
return VisitStmt(C, AddStmtChoice::AlwaysAdd);
|
|
}
|
|
|
|
if (Block) {
|
|
Succ = Block;
|
|
if (badCFG)
|
|
return 0;
|
|
}
|
|
|
|
Block = createBlock(!NoReturn);
|
|
AppendStmt(Block, C, asc);
|
|
|
|
if (NoReturn) {
|
|
// Wire this to the exit block directly.
|
|
AddSuccessor(Block, &cfg->getExit());
|
|
}
|
|
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, asc);
|
|
if (badCFG)
|
|
return 0;
|
|
|
|
asc = asc.asLValue() ? AddStmtChoice::AlwaysAddAsLValue
|
|
: AddStmtChoice::AlwaysAdd;
|
|
|
|
Succ = ConfluenceBlock;
|
|
Block = NULL;
|
|
CFGBlock* LHSBlock = Visit(C->getLHS(), asc);
|
|
if (badCFG)
|
|
return 0;
|
|
|
|
Succ = ConfluenceBlock;
|
|
Block = NULL;
|
|
CFGBlock* RHSBlock = Visit(C->getRHS(), asc);
|
|
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(ConditionalOperator *C,
|
|
AddStmtChoice asc) {
|
|
// Create the confluence block that will "merge" the results of the ternary
|
|
// expression.
|
|
CFGBlock* ConfluenceBlock = Block ? Block : createBlock();
|
|
AppendStmt(ConfluenceBlock, C, asc);
|
|
if (badCFG)
|
|
return 0;
|
|
|
|
asc = asc.asLValue() ? AddStmtChoice::AlwaysAddAsLValue
|
|
: AddStmtChoice::AlwaysAdd;
|
|
|
|
// 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 = NULL;
|
|
if (C->getLHS()) {
|
|
LHSBlock = Visit(C->getLHS(), asc);
|
|
if (badCFG)
|
|
return 0;
|
|
Block = NULL;
|
|
}
|
|
|
|
// Create the block for the RHS expression.
|
|
Succ = ConfluenceBlock;
|
|
CFGBlock* RHSBlock = Visit(C->getRHS(), asc);
|
|
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());
|
|
if (LHSBlock) {
|
|
AddSuccessor(Block, KnownVal.isFalse() ? NULL : LHSBlock);
|
|
} else {
|
|
if (KnownVal.isFalse()) {
|
|
// If we know the condition is false, add NULL as the successor for
|
|
// the block containing the condition. In this case, the confluence
|
|
// block will have just one predecessor.
|
|
AddSuccessor(Block, 0);
|
|
assert(ConfluenceBlock->pred_size() == 1);
|
|
} else {
|
|
// If we have no LHS expression, add the ConfluenceBlock as a direct
|
|
// successor for the block containing the condition. Moreover, we need to
|
|
// reverse the order of the predecessors in the ConfluenceBlock because
|
|
// the RHSBlock will have been added to the succcessors already, and we
|
|
// want the first predecessor to the the block containing the expression
|
|
// for the case when the ternary expression evaluates to true.
|
|
AddSuccessor(Block, ConfluenceBlock);
|
|
assert(ConfluenceBlock->pred_size() == 2);
|
|
std::reverse(ConfluenceBlock->pred_begin(),
|
|
ConfluenceBlock->pred_end());
|
|
}
|
|
}
|
|
|
|
AddSuccessor(Block, KnownVal.isTrue() ? NULL : RHSBlock);
|
|
Block->setTerminator(C);
|
|
return addStmt(C->getCond());
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitDeclStmt(DeclStmt *DS) {
|
|
if (DS->isSingleDecl())
|
|
return VisitDeclSubExpr(DS);
|
|
|
|
CFGBlock *B = 0;
|
|
|
|
// FIXME: Add a reverse iterator for DeclStmt to avoid this extra copy.
|
|
typedef llvm::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.");
|
|
|
|
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<CXXExprWithTemporaries>(Init);
|
|
|
|
if (BuildOpts.AddImplicitDtors && HasTemporaries) {
|
|
// Generate destructors for temporaries in initialization expression.
|
|
VisitForTemporaryDtors(cast<CXXExprWithTemporaries>(Init)->getSubExpr(),
|
|
IsReference);
|
|
}
|
|
}
|
|
|
|
autoCreateBlock();
|
|
AppendStmt(Block, DS);
|
|
|
|
if (Init) {
|
|
AddStmtChoice asc = IsReference
|
|
? AddStmtChoice::AsLValueNotAlwaysAdd
|
|
: AddStmtChoice::NotAlwaysAdd;
|
|
if (HasTemporaries)
|
|
// For expression with temporaries go directly to subexpression to omit
|
|
// generating destructors for the second time.
|
|
Visit(cast<CXXExprWithTemporaries>(Init)->getSubExpr(), asc);
|
|
else
|
|
Visit(Init, asc);
|
|
}
|
|
|
|
// If the type of VD is a VLA, then we must process its size expressions.
|
|
for (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;
|
|
}
|
|
|
|
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 proccessing 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, AddStmtChoice::AlwaysAdd);
|
|
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) == LabelMap.end() && "label already in map");
|
|
LabelMap[ L ] = 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::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.ScopePos, 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);
|
|
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, AddStmtChoice::AlwaysAdd);
|
|
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);
|
|
} else {
|
|
// 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()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, M, asc);
|
|
}
|
|
return Visit(M->getBase(),
|
|
M->isArrow() ? AddStmtChoice::NotAlwaysAdd
|
|
: AddStmtChoice::AsLValueNotAlwaysAdd);
|
|
}
|
|
|
|
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);
|
|
CFGBlock* EntryConditionBlock = ExitConditionBlock;
|
|
|
|
// 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 necesary. We DON'T add the statement by default to
|
|
// the CFG unless it contains control-flow.
|
|
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::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, AddStmtChoice::AlwaysAdd);
|
|
|
|
// Inline the sync expression.
|
|
return addStmt(S->getSynchExpr());
|
|
}
|
|
|
|
CFGBlock* CFGBuilder::VisitObjCAtTryStmt(ObjCAtTryStmt* S) {
|
|
// FIXME
|
|
return NYS();
|
|
}
|
|
|
|
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;
|
|
} 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, AddStmtChoice::AlwaysAdd);
|
|
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.ScopePos, C);
|
|
AddSuccessor(Block, ContinueJumpTarget.Block);
|
|
} else
|
|
badCFG = true;
|
|
|
|
return Block;
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E,
|
|
AddStmtChoice asc) {
|
|
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, E);
|
|
}
|
|
|
|
// VLA types have expressions that must be evaluated.
|
|
if (E->isArgumentType()) {
|
|
for (VariableArrayType* VA = FindVA(E->getArgumentType().getTypePtr());
|
|
VA != 0; VA = FindVA(VA->getElementType().getTypePtr()))
|
|
addStmt(VA->getSizeExpr());
|
|
}
|
|
|
|
return Block;
|
|
}
|
|
|
|
/// VisitStmtExpr - Utility method to handle (nested) statement
|
|
/// expressions (a GCC extension).
|
|
CFGBlock* CFGBuilder::VisitStmtExpr(StmtExpr *SE, AddStmtChoice asc) {
|
|
if (asc.alwaysAdd()) {
|
|
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;
|
|
|
|
// 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.
|
|
AddSuccessor(SwitchTerminatedBlock, DefaultCaseBlock);
|
|
|
|
// Add the terminator and condition in the switch block.
|
|
SwitchTerminatedBlock->setTerminator(Terminator);
|
|
assert(Terminator->getCond() && "switch condition must be non-NULL");
|
|
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, AddStmtChoice::AlwaysAdd);
|
|
addStmt(Init);
|
|
}
|
|
}
|
|
|
|
return Block;
|
|
}
|
|
|
|
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, CurrentBlock);
|
|
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, CaseBlock);
|
|
|
|
// 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);
|
|
TryTerminatedBlock = NewTryTerminatedBlock;
|
|
|
|
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();
|
|
|
|
CatchBlock->setLabel(CS);
|
|
|
|
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::VisitCXXExprWithTemporaries(CXXExprWithTemporaries *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.asLValue()
|
|
? AddStmtChoice::AlwaysAddAsLValue
|
|
: AddStmtChoice::AlwaysAdd;
|
|
}
|
|
return Visit(E->getSubExpr(), asc);
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E,
|
|
AddStmtChoice asc) {
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, E, asc);
|
|
|
|
// We do not want to propagate the AlwaysAdd property.
|
|
asc = AddStmtChoice(asc.asLValue() ? AddStmtChoice::AsLValueNotAlwaysAdd
|
|
: AddStmtChoice::NotAlwaysAdd);
|
|
}
|
|
return Visit(E->getSubExpr(), asc);
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitCXXConstructExpr(CXXConstructExpr *C,
|
|
AddStmtChoice asc) {
|
|
AddStmtChoice::Kind K = asc.asLValue() ? AddStmtChoice::AlwaysAddAsLValue
|
|
: AddStmtChoice::AlwaysAdd;
|
|
autoCreateBlock();
|
|
if (!C->isElidable())
|
|
AppendStmt(Block, C, AddStmtChoice(K));
|
|
return VisitChildren(C);
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E,
|
|
AddStmtChoice asc) {
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, E, asc);
|
|
// We do not want to propagate the AlwaysAdd property.
|
|
asc = AddStmtChoice(asc.asLValue() ? AddStmtChoice::AsLValueNotAlwaysAdd
|
|
: AddStmtChoice::NotAlwaysAdd);
|
|
}
|
|
return Visit(E->getSubExpr(), asc);
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *C,
|
|
AddStmtChoice asc) {
|
|
AddStmtChoice::Kind K = asc.asLValue() ? AddStmtChoice::AlwaysAddAsLValue
|
|
: AddStmtChoice::AlwaysAdd;
|
|
autoCreateBlock();
|
|
AppendStmt(Block, C, AddStmtChoice(K));
|
|
return VisitChildren(C);
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitCXXMemberCallExpr(CXXMemberCallExpr *C,
|
|
AddStmtChoice asc) {
|
|
AddStmtChoice::Kind K = asc.asLValue() ? AddStmtChoice::AlwaysAddAsLValue
|
|
: AddStmtChoice::AlwaysAdd;
|
|
autoCreateBlock();
|
|
AppendStmt(Block, C, AddStmtChoice(K));
|
|
return VisitChildren(C);
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitImplicitCastExpr(ImplicitCastExpr *E,
|
|
AddStmtChoice asc) {
|
|
if (asc.alwaysAdd()) {
|
|
autoCreateBlock();
|
|
AppendStmt(Block, E, asc);
|
|
// We do not want to propagate the AlwaysAdd property.
|
|
asc = AddStmtChoice(asc.asLValue() ? AddStmtChoice::AsLValueNotAlwaysAdd
|
|
: AddStmtChoice::NotAlwaysAdd);
|
|
}
|
|
return Visit(E->getSubExpr(), asc);
|
|
}
|
|
|
|
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::ConditionalOperatorClass:
|
|
return VisitConditionalOperatorForTemporaryDtors(
|
|
cast<ConditionalOperator>(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;
|
|
}
|
|
}
|
|
|
|
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 llvm::SmallVector<Stmt *, 4> ChildrenVect;
|
|
ChildrenVect ChildrenRev;
|
|
for (Stmt::child_iterator I = E->child_begin(), L = E->child_end();
|
|
I != L; ++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;
|
|
}
|
|
|
|
else 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.
|
|
autoCreateBlock();
|
|
appendTemporaryDtor(Block, E);
|
|
B = Block;
|
|
}
|
|
return B;
|
|
}
|
|
|
|
CFGBlock *CFGBuilder::VisitConditionalOperatorForTemporaryDtors(
|
|
ConditionalOperator *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;
|
|
|
|
// Try to add block with destructors for LHS expression.
|
|
CFGBlock *LHSBlock = NULL;
|
|
if (E->getLHS()) {
|
|
Succ = ConfluenceBlock;
|
|
Block = NULL;
|
|
LHSBlock = VisitForTemporaryDtors(E->getLHS(), BindToTemporary);
|
|
if (badCFG)
|
|
return NULL;
|
|
}
|
|
|
|
// Try to add block with destructors for RHS expression;
|
|
Succ = ConfluenceBlock;
|
|
Block = NULL;
|
|
CFGBlock *RHSBlock = VisitForTemporaryDtors(E->getRHS(), 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);
|
|
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,
|
|
BuildOptions BO) {
|
|
CFGBuilder Builder;
|
|
return Builder.buildCFG(D, Statement, C, BO);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// CFG: Queries for BlkExprs.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
typedef llvm::DenseMap<const Stmt*,unsigned> BlkExprMapTy;
|
|
}
|
|
|
|
static void FindSubExprAssignments(Stmt *S,
|
|
llvm::SmallPtrSet<Expr*,50>& Set) {
|
|
if (!S)
|
|
return;
|
|
|
|
for (Stmt::child_iterator I=S->child_begin(), E=S->child_end(); I!=E; ++I) {
|
|
Stmt *child = *I;
|
|
if (!child)
|
|
continue;
|
|
|
|
if (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<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 (CFGStmt S = BI->getAs<CFGStmt>())
|
|
FindSubExprAssignments(S, 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) {
|
|
CFGStmt CS = BI->getAs<CFGStmt>();
|
|
if (!CS.isValid())
|
|
continue;
|
|
if (Expr* Exp = dyn_cast<Expr>(CS.getStmt())) {
|
|
|
|
if (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* Terminator = 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 = Terminator->getSubStmt();
|
|
if (!C->body_empty()) {
|
|
unsigned x = M->size();
|
|
(*M)[C->body_back()] = 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();
|
|
else {
|
|
// 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 (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<Stmt*,std::pair<unsigned,unsigned> > StmtMapTy;
|
|
typedef llvm::DenseMap<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 (CFGStmt SE = BI->getAs<CFGStmt>()) {
|
|
std::pair<unsigned, unsigned> P((*I)->getBlockID(), j);
|
|
StmtMap[SE] = P;
|
|
|
|
if (DeclStmt* DS = dyn_cast<DeclStmt>(SE.getStmt())) {
|
|
DeclMap[DS->getSingleDecl()] = P;
|
|
|
|
} else if (IfStmt* IS = dyn_cast<IfStmt>(SE.getStmt())) {
|
|
if (VarDecl* VD = IS->getConditionVariable())
|
|
DeclMap[VD] = P;
|
|
|
|
} else if (ForStmt* FS = dyn_cast<ForStmt>(SE.getStmt())) {
|
|
if (VarDecl* VD = FS->getConditionVariable())
|
|
DeclMap[VD] = P;
|
|
|
|
} else if (WhileStmt* WS = dyn_cast<WhileStmt>(SE.getStmt())) {
|
|
if (VarDecl* VD = WS->getConditionVariable())
|
|
DeclMap[VD] = P;
|
|
|
|
} else if (SwitchStmt* SS = dyn_cast<SwitchStmt>(SE.getStmt())) {
|
|
if (VarDecl* VD = SS->getConditionVariable())
|
|
DeclMap[VD] = P;
|
|
|
|
} else if (CXXCatchStmt* CS = dyn_cast<CXXCatchStmt>(SE.getStmt())) {
|
|
if (VarDecl* VD = CS->getExceptionDecl())
|
|
DeclMap[VD] = P;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
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, llvm::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(Decl* D, llvm::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> {
|
|
|
|
llvm::raw_ostream& OS;
|
|
StmtPrinterHelper* Helper;
|
|
PrintingPolicy Policy;
|
|
public:
|
|
CFGBlockTerminatorPrint(llvm::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 VisitConditionalOperator(ConditionalOperator* 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:
|
|
assert(false && "Invalid logical operator.");
|
|
}
|
|
}
|
|
|
|
void VisitExpr(Expr* E) {
|
|
E->printPretty(OS, Helper, Policy);
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
static void print_elem(llvm::raw_ostream &OS, StmtPrinterHelper* Helper,
|
|
const CFGElement &E) {
|
|
if (CFGStmt CS = E.getAs<CFGStmt>()) {
|
|
Stmt *S = CS;
|
|
|
|
if (Helper) {
|
|
|
|
// special printing for statement-expressions.
|
|
if (StmtExpr* SE = dyn_cast<StmtExpr>(S)) {
|
|
CompoundStmt* Sub = SE->getSubStmt();
|
|
|
|
if (Sub->child_begin() != Sub->child_end()) {
|
|
OS << "({ ... ; ";
|
|
Helper->handledStmt(*SE->getSubStmt()->body_rbegin(),OS);
|
|
OS << " })\n";
|
|
return;
|
|
}
|
|
}
|
|
// special printing for comma expressions.
|
|
if (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)";
|
|
}
|
|
|
|
// Expressions need a newline.
|
|
if (isa<Expr>(S))
|
|
OS << '\n';
|
|
|
|
} else if (CFGInitializer IE = E.getAs<CFGInitializer>()) {
|
|
CXXBaseOrMemberInitializer* I = IE;
|
|
if (I->isBaseInitializer())
|
|
OS << I->getBaseClass()->getAsCXXRecordDecl()->getName();
|
|
else OS << I->getMember()->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 (CFGAutomaticObjDtor DE = E.getAs<CFGAutomaticObjDtor>()){
|
|
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 (CFGBaseDtor BE = E.getAs<CFGBaseDtor>()) {
|
|
const CXXBaseSpecifier *BS = BE.getBaseSpecifier();
|
|
OS << "~" << BS->getType()->getAsCXXRecordDecl()->getName() << "()";
|
|
OS << " (Base object destructor)\n";
|
|
|
|
} else if (CFGMemberDtor ME = E.getAs<CFGMemberDtor>()) {
|
|
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 (CFGTemporaryDtor TE = E.getAs<CFGTemporaryDtor>()) {
|
|
CXXBindTemporaryExpr *BT = TE.getBindTemporaryExpr();
|
|
OS << "~" << BT->getType()->getAsCXXRecordDecl()->getName() << "()";
|
|
OS << " (Temporary object destructor)\n";
|
|
}
|
|
}
|
|
|
|
static void print_block(llvm::raw_ostream& OS, const CFG* cfg,
|
|
const CFGBlock& B,
|
|
StmtPrinterHelper* Helper, bool print_edges) {
|
|
|
|
if (Helper) Helper->setBlockID(B.getBlockID());
|
|
|
|
// Print the header.
|
|
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";
|
|
|
|
// 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
|
|
assert(false && "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 (print_edges)
|
|
OS << " ";
|
|
|
|
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 (print_edges) {
|
|
// Print the predecessors of this block.
|
|
OS << " Predecessors (" << B.pred_size() << "):";
|
|
unsigned i = 0;
|
|
|
|
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();
|
|
}
|
|
|
|
OS << '\n';
|
|
|
|
// Print the successors of this block.
|
|
OS << " Successors (" << B.succ_size() << "):";
|
|
i = 0;
|
|
|
|
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";
|
|
}
|
|
|
|
OS << '\n';
|
|
}
|
|
}
|
|
|
|
|
|
/// dump - A simple pretty printer of a CFG that outputs to stderr.
|
|
void CFG::dump(const LangOptions &LO) const { print(llvm::errs(), LO); }
|
|
|
|
/// print - A simple pretty printer of a CFG that outputs to an ostream.
|
|
void CFG::print(llvm::raw_ostream &OS, const LangOptions &LO) const {
|
|
StmtPrinterHelper Helper(this, LO);
|
|
|
|
// Print the entry block.
|
|
print_block(OS, this, getEntry(), &Helper, true);
|
|
|
|
// 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);
|
|
}
|
|
|
|
// Print the exit block.
|
|
print_block(OS, this, getExit(), &Helper, true);
|
|
OS.flush();
|
|
}
|
|
|
|
/// dump - A simply pretty printer of a CFGBlock that outputs to stderr.
|
|
void CFGBlock::dump(const CFG* cfg, const LangOptions &LO) const {
|
|
print(llvm::errs(), cfg, LO);
|
|
}
|
|
|
|
/// 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(llvm::raw_ostream& OS, const CFG* cfg,
|
|
const LangOptions &LO) const {
|
|
StmtPrinterHelper Helper(cfg, LO);
|
|
print_block(OS, cfg, *this, &Helper, true);
|
|
}
|
|
|
|
/// printTerminator - A simple pretty printer of the terminator of a CFGBlock.
|
|
void CFGBlock::printTerminator(llvm::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::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;
|
|
}
|
|
|
|
bool CFGBlock::hasBinaryBranchTerminator() const {
|
|
const Stmt *Terminator = this->Terminator;
|
|
if (!Terminator)
|
|
return false;
|
|
|
|
Expr* E = NULL;
|
|
|
|
switch (Terminator->getStmtClass()) {
|
|
default:
|
|
return false;
|
|
|
|
case Stmt::ForStmtClass:
|
|
case Stmt::WhileStmtClass:
|
|
case Stmt::DoStmtClass:
|
|
case Stmt::IfStmtClass:
|
|
case Stmt::ChooseExprClass:
|
|
case Stmt::ConditionalOperatorClass:
|
|
case Stmt::BinaryOperatorClass:
|
|
return true;
|
|
}
|
|
|
|
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);
|
|
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
|