Anna Zaks | 196b8cf | 2012-03-08 00:42:23 +0000 | [diff] [blame] | 1 | //== CallGraph.cpp - AST-based Call graph ----------------------*- C++ -*--==// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | // |
| 10 | // This file defines the AST-based CallGraph. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | #include "clang/Analysis/CallGraph.h" |
| 14 | |
| 15 | #include "clang/AST/ASTContext.h" |
| 16 | #include "clang/AST/Decl.h" |
| 17 | #include "clang/AST/StmtVisitor.h" |
| 18 | |
| 19 | #include "llvm/Support/GraphWriter.h" |
| 20 | |
| 21 | using namespace clang; |
| 22 | |
| 23 | /// Determine if a declaration should be included in the graph. |
| 24 | static bool includeInGraph(const Decl *D) { |
| 25 | if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { |
| 26 | // We skip function template definitions, as their semantics is |
| 27 | // only determined when they are instantiated. |
| 28 | if (!FD->isThisDeclarationADefinition() || |
| 29 | FD->isDependentContext()) |
| 30 | return false; |
| 31 | |
| 32 | IdentifierInfo *II = FD->getIdentifier(); |
| 33 | if (II && II->getName().startswith("__inline")) |
| 34 | return false; |
| 35 | } |
| 36 | |
| 37 | if (const ObjCMethodDecl *ID = dyn_cast<ObjCMethodDecl>(D)) { |
| 38 | if (!ID->isThisDeclarationADefinition()) |
| 39 | return false; |
| 40 | } |
| 41 | |
| 42 | return true; |
| 43 | } |
| 44 | |
| 45 | namespace { |
| 46 | /// A helper class, which walks the AST and locates all the call sites in the |
| 47 | /// given function body. |
| 48 | class CGBuilder : public StmtVisitor<CGBuilder> { |
| 49 | CallGraph *G; |
| 50 | const Decl *FD; |
| 51 | CallGraphNode *CallerNode; |
| 52 | |
| 53 | public: |
| 54 | CGBuilder(CallGraph *g, const Decl *D, CallGraphNode *N) |
| 55 | : G(g), FD(D), CallerNode(N) {} |
| 56 | |
| 57 | void VisitStmt(Stmt *S) { VisitChildren(S); } |
| 58 | |
| 59 | void VisitCallExpr(CallExpr *CE) { |
| 60 | // TODO: We need to handle ObjC method calls as well. |
| 61 | if (FunctionDecl *CalleeDecl = CE->getDirectCallee()) |
| 62 | if (includeInGraph(CalleeDecl)) { |
| 63 | CallGraphNode *CalleeNode = G->getOrInsertFunction(CalleeDecl); |
| 64 | CallerNode->addCallee(CalleeNode, G); |
| 65 | } |
Daniel Dunbar | a50a5cd | 2012-03-08 20:28:59 +0000 | [diff] [blame] | 66 | } |
Anna Zaks | 196b8cf | 2012-03-08 00:42:23 +0000 | [diff] [blame] | 67 | |
| 68 | void VisitChildren(Stmt *S) { |
| 69 | for (Stmt::child_range I = S->children(); I; ++I) |
| 70 | if (*I) |
| 71 | static_cast<CGBuilder*>(this)->Visit(*I); |
| 72 | } |
| 73 | }; |
| 74 | } // end anonymous namespace |
| 75 | |
| 76 | CallGraph::CallGraph() { |
| 77 | Root = getOrInsertFunction(0); |
| 78 | } |
| 79 | |
| 80 | CallGraph::~CallGraph() { |
| 81 | if (!FunctionMap.empty()) { |
| 82 | for (FunctionMapTy::iterator I = FunctionMap.begin(), E = FunctionMap.end(); |
| 83 | I != E; ++I) |
| 84 | delete I->second; |
| 85 | FunctionMap.clear(); |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | void CallGraph::addToCallGraph(Decl* D, bool IsGlobal) { |
Anna Zaks | d277661 | 2012-03-08 23:16:26 +0000 | [diff] [blame^] | 90 | assert(D); |
Anna Zaks | 196b8cf | 2012-03-08 00:42:23 +0000 | [diff] [blame] | 91 | CallGraphNode *Node = getOrInsertFunction(D); |
| 92 | |
| 93 | if (IsGlobal) |
| 94 | Root->addCallee(Node, this); |
| 95 | |
| 96 | // Process all the calls by this function as well. |
| 97 | CGBuilder builder(this, D, Node); |
| 98 | builder.Visit(D->getBody()); |
| 99 | } |
| 100 | |
| 101 | void CallGraph::addToCallGraph(DeclContext *DC) { |
| 102 | for (DeclContext::decl_iterator I = DC->decls_begin(), E = DC->decls_end(); |
| 103 | I != E; ++I) { |
| 104 | Decl *D = *I; |
| 105 | switch (D->getKind()) { |
| 106 | case Decl::CXXConstructor: |
| 107 | case Decl::CXXDestructor: |
| 108 | case Decl::CXXConversion: |
| 109 | case Decl::CXXMethod: |
| 110 | case Decl::Function: { |
| 111 | FunctionDecl *FD = cast<FunctionDecl>(D); |
| 112 | // We skip function template definitions, as their semantics is |
| 113 | // only determined when they are instantiated. |
| 114 | if (includeInGraph(FD)) |
| 115 | // If this function has external linkage, anything could call it. |
| 116 | // Note, we are not precise here. For example, the function could have |
| 117 | // its address taken. |
| 118 | addToCallGraph(FD, FD->isGlobal()); |
| 119 | break; |
| 120 | } |
| 121 | |
| 122 | case Decl::ObjCCategoryImpl: |
| 123 | case Decl::ObjCImplementation: { |
| 124 | ObjCImplDecl *ID = cast<ObjCImplDecl>(D); |
| 125 | for (ObjCContainerDecl::method_iterator MI = ID->meth_begin(), |
| 126 | ME = ID->meth_end(); MI != ME; ++MI) { |
| 127 | if (includeInGraph(*MI)) |
| 128 | addToCallGraph(*MI, true); |
| 129 | } |
| 130 | break; |
| 131 | } |
| 132 | |
| 133 | default: |
| 134 | break; |
| 135 | } |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | CallGraphNode *CallGraph::getOrInsertFunction(Decl *F) { |
| 140 | CallGraphNode *&Node = FunctionMap[F]; |
| 141 | if (Node) |
| 142 | return Node; |
| 143 | |
| 144 | Node = new CallGraphNode(F); |
Anna Zaks | d277661 | 2012-03-08 23:16:26 +0000 | [diff] [blame^] | 145 | // If not root, add to the parentless list. |
| 146 | if (F != 0) |
| 147 | ParentlessNodes.insert(Node); |
Anna Zaks | 196b8cf | 2012-03-08 00:42:23 +0000 | [diff] [blame] | 148 | return Node; |
| 149 | } |
| 150 | |
| 151 | void CallGraph::print(raw_ostream &OS) const { |
| 152 | OS << " --- Call graph Dump --- \n"; |
| 153 | for (const_iterator I = begin(), E = end(); I != E; ++I) { |
| 154 | OS << " Function: "; |
| 155 | if (I->second == Root) |
| 156 | OS << "< root >"; |
| 157 | else |
| 158 | I->second->print(OS); |
| 159 | OS << " calls: "; |
| 160 | for (CallGraphNode::iterator CI = I->second->begin(), |
| 161 | CE = I->second->end(); CI != CE; ++CI) { |
| 162 | assert(*CI != Root && "No one can call the root node."); |
| 163 | (*CI)->print(OS); |
| 164 | OS << " "; |
| 165 | } |
| 166 | OS << '\n'; |
| 167 | } |
| 168 | OS.flush(); |
| 169 | } |
| 170 | |
| 171 | void CallGraph::dump() const { |
| 172 | print(llvm::errs()); |
| 173 | } |
| 174 | |
| 175 | void CallGraph::viewGraph() const { |
| 176 | llvm::ViewGraph(this, "CallGraph"); |
| 177 | } |
| 178 | |
| 179 | StringRef CallGraphNode::getName() const { |
| 180 | if (const FunctionDecl *D = dyn_cast_or_null<FunctionDecl>(FD)) |
| 181 | if (const IdentifierInfo *II = D->getIdentifier()) |
| 182 | return II->getName(); |
| 183 | return "< >"; |
| 184 | } |
| 185 | |
| 186 | void CallGraphNode::print(raw_ostream &os) const { |
| 187 | os << getName(); |
| 188 | } |
| 189 | |
| 190 | void CallGraphNode::dump() const { |
| 191 | print(llvm::errs()); |
| 192 | } |
| 193 | |
| 194 | namespace llvm { |
| 195 | |
| 196 | template <> |
| 197 | struct DOTGraphTraits<const CallGraph*> : public DefaultDOTGraphTraits { |
| 198 | |
| 199 | DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} |
| 200 | |
| 201 | static std::string getNodeLabel(const CallGraphNode *Node, |
| 202 | const CallGraph *CG) { |
| 203 | if (CG->getRoot() == Node) { |
| 204 | return "< root >"; |
| 205 | } |
| 206 | return Node->getName(); |
| 207 | } |
| 208 | |
| 209 | }; |
| 210 | } |