/// 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.
+/// 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
#include "llvm/ADT/GraphTraits.h"
#include "llvm/ADT/STLExtras.h"
+#include "llvm/IR/CallSite.h"
#include "llvm/IR/Function.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 <map>
namespace llvm {
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<const Function *, CallGraphNode *> FunctionMapTy;
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(); }
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; }
-
//===---------------------------------------------------------------------
// Functions to keep a call graph up to date with a function that has been
// modified.
/// \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.
/// 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<Function> F;
-
public:
/// \brief A pair of the calling instruction (a call or invoke)
/// and the call graph node being called.
typedef std::pair<WeakVH, CallGraphNode *> CallRecord;
-private:
- std::vector<CallRecord> 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<CallRecord> CalledFunctionsVector;
/// 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<Function> F;
+
+ std::vector<CallRecord> 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; }
+
/// \brief A special function that should only be used by the CallGraph class.
- //
- // FIXME: Make this private?
void allReferencesDropped() { NumReferences = 0; }
};
+/// \brief An analysis pass to compute the \c CallGraph for a \c Module.
+///
+/// This class implements the concept of an analysis pass used by the \c
+/// ModuleAnalysisManager to run an analysis over a module and cache the
+/// resulting data.
+class CallGraphAnalysis {
+public:
+ /// \brief A formulaic typedef to inform clients of the result type.
+ typedef CallGraph Result;
+
+ static void *ID() { return (void *)&PassID; }
+
+ /// \brief Compute the \c CallGraph for the module \c M.
+ ///
+ /// The real work here is done in the \c CallGraph constructor.
+ CallGraph run(Module *M) { return CallGraph(*M); }
+
+private:
+ static char PassID;
+};
+
+/// \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<CallGraph> G;
+
+public:
+ static char ID; // Class identification, replacement for typeinfo
+
+ CallGraphWrapperPass();
+ virtual ~CallGraphWrapperPass();
+
+ /// \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.