X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FAnalysis%2FCallGraph.h;h=651d1901f3e7e444cfafee88e4e01c868692ddc8;hb=0d2d02d317247c811e79ad80a0c027ea1d867c1a;hp=8a2355ec5ce646aa6f062c27a6a82ca179220fee;hpb=a8a39b15951927ad007db6223d9c5793e523a373;p=oota-llvm.git diff --git a/include/llvm/Analysis/CallGraph.h b/include/llvm/Analysis/CallGraph.h index 8a2355ec5ce..651d1901f3e 100644 --- a/include/llvm/Analysis/CallGraph.h +++ b/include/llvm/Analysis/CallGraph.h @@ -6,46 +6,47 @@ // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// -// -// This interface is used to build and manipulate a call graph, which is a very -// useful tool for interprocedural optimization. -// -// Every function in a module is represented as a node in the call graph. The -// callgraph node keeps track of which functions the are called by the function -// corresponding to the node. -// -// A call graph may contain nodes where the function that they correspond to is -// null. These 'external' nodes are used to represent control flow that is not -// represented (or analyzable) in the module. In particular, this analysis -// builds one external node such that: -// 1. All functions in the module without internal linkage will have edges -// from this external node, indicating that they could be called by -// functions outside of the module. -// 2. All functions whose address is used for something more than a direct -// call, for example being stored into a memory location will also have an -// edge from this external node. Since they may be called by an unknown -// caller later, they must be tracked as such. -// -// There is a second external node added for calls that leave this module. -// Functions have a call edge to the external node iff: -// 1. The function is external, reflecting the fact that they could call -// anything without internal linkage or that has its address taken. -// 2. The function contains an indirect function call. -// -// As an extension in the future, there may be multiple nodes with a null -// function. These will be used when we can prove (through pointer analysis) -// that an indirect call site can call only a specific set of functions. -// -// Because of these properties, the CallGraph captures a conservative superset -// of all of the caller-callee relationships, which is useful for -// transformations. -// -// The CallGraph class also attempts to figure out what the root of the -// CallGraph is, which it currently does by looking for a function named 'main'. -// If no function named 'main' is found, the external node is used as the entry -// node, reflecting the fact that any function without internal linkage could -// be called into (which is common for libraries). -// +/// \file +/// +/// This file provides interfaces used to build and manipulate a call graph, +/// which is a very useful tool for interprocedural optimization. +/// +/// Every function in a module is represented as a node in the call graph. The +/// callgraph node keeps track of which functions are called by the function +/// corresponding to the node. +/// +/// A call graph may contain nodes where the function that they correspond to +/// is null. These 'external' nodes are used to represent control flow that is +/// not represented (or analyzable) in the module. In particular, this +/// analysis builds one external node such that: +/// 1. All functions in the module without internal linkage will have edges +/// from this external node, indicating that they could be called by +/// functions outside of the module. +/// 2. All functions whose address is used for something more than a direct +/// call, for example being stored into a memory location will also have +/// an edge from this external node. Since they may be called by an +/// unknown caller later, they must be tracked as such. +/// +/// There is a second external node added for calls that leave this module. +/// Functions have a call edge to the external node iff: +/// 1. The function is external, reflecting the fact that they could call +/// anything without internal linkage or that has its address taken. +/// 2. The function contains an indirect function call. +/// +/// As an extension in the future, there may be multiple nodes with a null +/// function. These will be used when we can prove (through pointer analysis) +/// that an indirect call site can call only a specific set of functions. +/// +/// Because of these properties, the CallGraph captures a conservative superset +/// of all of the caller-callee relationships, which is useful for +/// transformations. +/// +/// The CallGraph class also attempts to figure out what the root of the +/// CallGraph is, which it currently does by looking for a function named +/// 'main'. If no function named 'main' is found, the external node is used as +/// the entry node, reflecting the fact that any function without internal +/// linkage could be called into (which is common for libraries). +/// //===----------------------------------------------------------------------===// #ifndef LLVM_ANALYSIS_CALLGRAPH_H @@ -53,11 +54,11 @@ #include "llvm/ADT/GraphTraits.h" #include "llvm/ADT/STLExtras.h" +#include "llvm/IR/CallSite.h" #include "llvm/IR/Function.h" +#include "llvm/IR/Intrinsics.h" +#include "llvm/IR/ValueHandle.h" #include "llvm/Pass.h" -#include "llvm/Support/CallSite.h" -#include "llvm/Support/IncludeFile.h" -#include "llvm/Support/ValueHandle.h" #include namespace llvm { @@ -66,17 +67,16 @@ class Function; class Module; class CallGraphNode; -/// \brief The basic data container for the call graph and the \c ModulePass -/// which produces it. +/// \brief The basic data container for the call graph of a \c Module of IR. /// -/// This class exposes both the interface to the call graph container and the -/// module pass which runs over a module of IR and produces the call graph. +/// This class exposes both the interface to the call graph for a module of IR. /// /// The core call graph itself can also be updated to reflect changes to the IR. -class CallGraph : public ModulePass { - Module *M; +class CallGraph { + Module &M; - typedef std::map FunctionMapTy; + typedef std::map> + FunctionMapTy; /// \brief A map from \c Function* to \c CallGraphNode*. FunctionMapTy FunctionMap; @@ -91,7 +91,7 @@ class CallGraph : public ModulePass { /// \brief This node has edges to it from all functions making indirect calls /// or calling an external function. - CallGraphNode *CallsExternalNode; + std::unique_ptr CallsExternalNode; /// \brief Replace the function represented by this node by another. /// @@ -105,13 +105,17 @@ class CallGraph : public ModulePass { void addToCallGraph(Function *F); public: - static char ID; // Class identification, replacement for typeinfo + CallGraph(Module &M); + ~CallGraph(); + + void print(raw_ostream &OS) const; + void dump() const; typedef FunctionMapTy::iterator iterator; typedef FunctionMapTy::const_iterator const_iterator; /// \brief Returns the module the call graph corresponds to. - Module &getModule() const { return *M; } + Module &getModule() const { return M; } inline iterator begin() { return FunctionMap.begin(); } inline iterator end() { return FunctionMap.end(); } @@ -122,26 +126,23 @@ public: inline const CallGraphNode *operator[](const Function *F) const { const_iterator I = FunctionMap.find(F); assert(I != FunctionMap.end() && "Function not in callgraph!"); - return I->second; + return I->second.get(); } /// \brief Returns the call graph node for the provided function. inline CallGraphNode *operator[](const Function *F) { const_iterator I = FunctionMap.find(F); assert(I != FunctionMap.end() && "Function not in callgraph!"); - return I->second; + return I->second.get(); } /// \brief Returns the \c CallGraphNode which is used to represent /// undetermined calls into the callgraph. CallGraphNode *getExternalCallingNode() const { return ExternalCallingNode; } - CallGraphNode *getCallsExternalNode() const { return CallsExternalNode; } - - /// \brief Returns the root/main method in the module, or some other root - /// node, such as the externalcallingnode. - CallGraphNode *getRoot() { return Root; } - const CallGraphNode *getRoot() const { return Root; } + CallGraphNode *getCallsExternalNode() const { + return CallsExternalNode.get(); + } //===--------------------------------------------------------------------- // Functions to keep a call graph up to date with a function that has been @@ -159,20 +160,6 @@ public: /// \brief Similar to operator[], but this will insert a new CallGraphNode for /// \c F if one does not already exist. CallGraphNode *getOrInsertFunction(const Function *F); - - CallGraph(); - virtual ~CallGraph() { releaseMemory(); } - - //===--------------------------------------------------------------------- - // Implementation of the ModulePass interface needed here. - // - - virtual void getAnalysisUsage(AnalysisUsage &AU) const; - virtual bool runOnModule(Module &M); - virtual void releaseMemory(); - - void print(raw_ostream &o, const Module *) const; - void dump() const; }; /// \brief A node in the call graph for a module. @@ -180,28 +167,11 @@ public: /// Typically represents a function in the call graph. There are also special /// "null" nodes used to represent theoretical entries in the call graph. class CallGraphNode { - friend class CallGraph; - - AssertingVH F; - public: /// \brief A pair of the calling instruction (a call or invoke) /// and the call graph node being called. typedef std::pair CallRecord; -private: - std::vector CalledFunctions; - - /// \brief The number of times that this CallGraphNode occurs in the - /// CalledFunctions array of this or other CallGraphNodes. - unsigned NumReferences; - - CallGraphNode(const CallGraphNode &) LLVM_DELETED_FUNCTION; - void operator=(const CallGraphNode &) LLVM_DELETED_FUNCTION; - - void DropRef() { --NumReferences; } - void AddRef() { ++NumReferences; } - public: typedef std::vector CalledFunctionsVector; @@ -263,8 +233,9 @@ public: /// \brief Adds a function to the list of functions called by this one. void addCalledFunction(CallSite CS, CallGraphNode *M) { assert(!CS.getInstruction() || !CS.getCalledFunction() || - !CS.getCalledFunction()->isIntrinsic()); - CalledFunctions.push_back(std::make_pair(CS.getInstruction(), M)); + !CS.getCalledFunction()->isIntrinsic() || + !Intrinsic::isLeaf(CS.getCalledFunction()->getIntrinsicID())); + CalledFunctions.emplace_back(CS.getInstruction(), M); M->AddRef(); } @@ -296,12 +267,110 @@ public: /// Note that this method takes linear time, so it should be used sparingly. void replaceCallEdge(CallSite CS, CallSite NewCS, CallGraphNode *NewNode); +private: + friend class CallGraph; + + AssertingVH F; + + std::vector CalledFunctions; + + /// \brief The number of times that this CallGraphNode occurs in the + /// CalledFunctions array of this or other CallGraphNodes. + unsigned NumReferences; + + CallGraphNode(const CallGraphNode &) = delete; + void operator=(const CallGraphNode &) = delete; + + void DropRef() { --NumReferences; } + void AddRef() { ++NumReferences; } + /// \brief A special function that should only be used by the CallGraph class. - // - // FIXME: Make this private? void allReferencesDropped() { NumReferences = 0; } }; +/// \brief The \c ModulePass which wraps up a \c CallGraph and the logic to +/// build it. +/// +/// This class exposes both the interface to the call graph container and the +/// module pass which runs over a module of IR and produces the call graph. The +/// call graph interface is entirelly a wrapper around a \c CallGraph object +/// which is stored internally for each module. +class CallGraphWrapperPass : public ModulePass { + std::unique_ptr G; + +public: + static char ID; // Class identification, replacement for typeinfo + + CallGraphWrapperPass(); + ~CallGraphWrapperPass() override; + + /// \brief The internal \c CallGraph around which the rest of this interface + /// is wrapped. + const CallGraph &getCallGraph() const { return *G; } + CallGraph &getCallGraph() { return *G; } + + typedef CallGraph::iterator iterator; + typedef CallGraph::const_iterator const_iterator; + + /// \brief Returns the module the call graph corresponds to. + Module &getModule() const { return G->getModule(); } + + inline iterator begin() { return G->begin(); } + inline iterator end() { return G->end(); } + inline const_iterator begin() const { return G->begin(); } + inline const_iterator end() const { return G->end(); } + + /// \brief Returns the call graph node for the provided function. + inline const CallGraphNode *operator[](const Function *F) const { + return (*G)[F]; + } + + /// \brief Returns the call graph node for the provided function. + inline CallGraphNode *operator[](const Function *F) { return (*G)[F]; } + + /// \brief Returns the \c CallGraphNode which is used to represent + /// undetermined calls into the callgraph. + CallGraphNode *getExternalCallingNode() const { + return G->getExternalCallingNode(); + } + + CallGraphNode *getCallsExternalNode() const { + return G->getCallsExternalNode(); + } + + //===--------------------------------------------------------------------- + // Functions to keep a call graph up to date with a function that has been + // modified. + // + + /// \brief Unlink the function from this module, returning it. + /// + /// Because this removes the function from the module, the call graph node is + /// destroyed. This is only valid if the function does not call any other + /// functions (ie, there are no edges in it's CGN). The easiest way to do + /// this is to dropAllReferences before calling this. + Function *removeFunctionFromModule(CallGraphNode *CGN) { + return G->removeFunctionFromModule(CGN); + } + + /// \brief Similar to operator[], but this will insert a new CallGraphNode for + /// \c F if one does not already exist. + CallGraphNode *getOrInsertFunction(const Function *F) { + return G->getOrInsertFunction(F); + } + + //===--------------------------------------------------------------------- + // Implementation of the ModulePass interface needed here. + // + + void getAnalysisUsage(AnalysisUsage &AU) const override; + bool runOnModule(Module &M) override; + void releaseMemory() override; + + void print(raw_ostream &o, const Module *) const override; + void dump() const; +}; + //===----------------------------------------------------------------------===// // GraphTraits specializations for call graphs so that they can be treated as // graphs by the generic graph algorithms. @@ -332,13 +401,24 @@ template <> struct GraphTraits { template <> struct GraphTraits { typedef const CallGraphNode NodeType; - typedef NodeType::const_iterator ChildIteratorType; + + typedef CallGraphNode::CallRecord CGNPairTy; + typedef std::pointer_to_unary_function + CGNDerefFun; static NodeType *getEntryNode(const CallGraphNode *CGN) { return CGN; } + + typedef mapped_iterator + ChildIteratorType; + static inline ChildIteratorType child_begin(NodeType *N) { - return N->begin(); + return map_iterator(N->begin(), CGNDerefFun(CGNDeref)); + } + static inline ChildIteratorType child_end(NodeType *N) { + return map_iterator(N->end(), CGNDerefFun(CGNDeref)); } - static inline ChildIteratorType child_end(NodeType *N) { return N->end(); } + + static const CallGraphNode *CGNDeref(CGNPairTy P) { return P.second; } }; template <> @@ -346,8 +426,10 @@ struct GraphTraits : public GraphTraits { static NodeType *getEntryNode(CallGraph *CGN) { return CGN->getExternalCallingNode(); // Start at the external node! } - typedef std::pair PairTy; - typedef std::pointer_to_unary_function DerefFun; + typedef std::pair> + PairTy; + typedef std::pointer_to_unary_function + DerefFun; // nodes_iterator/begin/end - Allow iteration over all nodes in the graph typedef mapped_iterator nodes_iterator; @@ -358,24 +440,34 @@ struct GraphTraits : public GraphTraits { return map_iterator(CG->end(), DerefFun(CGdereference)); } - static CallGraphNode &CGdereference(PairTy P) { return *P.second; } + static CallGraphNode &CGdereference(const PairTy &P) { return *P.second; } }; template <> struct GraphTraits : public GraphTraits< const CallGraphNode *> { static NodeType *getEntryNode(const CallGraph *CGN) { - return CGN->getExternalCallingNode(); + return CGN->getExternalCallingNode(); // Start at the external node! } + typedef std::pair> + PairTy; + typedef std::pointer_to_unary_function + DerefFun; + // nodes_iterator/begin/end - Allow iteration over all nodes in the graph - typedef CallGraph::const_iterator nodes_iterator; - static nodes_iterator nodes_begin(const CallGraph *CG) { return CG->begin(); } - static nodes_iterator nodes_end(const CallGraph *CG) { return CG->end(); } + typedef mapped_iterator nodes_iterator; + static nodes_iterator nodes_begin(const CallGraph *CG) { + return map_iterator(CG->begin(), DerefFun(CGdereference)); + } + static nodes_iterator nodes_end(const CallGraph *CG) { + return map_iterator(CG->end(), DerefFun(CGdereference)); + } + + static const CallGraphNode &CGdereference(const PairTy &P) { + return *P.second; + } }; } // End llvm namespace -// Make sure that any clients of this file link in CallGraph.cpp -FORCE_DEFINING_FILE_TO_BE_LINKED(CallGraph) - #endif