llvm-6502/include/llvm/Analysis/CallGraph.h
Chris Lattner 8bbc979052 Implement an entry node for the call graph
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1363 91177308-0d34-0410-b5e6-96231b3b80d8
2001-11-26 18:47:11 +00:00

174 lines
5.8 KiB
C++

//===- llvm/Analysis/CallGraph.h - Build a Module's call graph ---*- C++ -*--=//
//
// This interface is used to build and manipulate a call graph, which is a very
// useful tool for interprocedural optimization.
//
// This call graph represents a dynamic method invocation as a null method node.
// A call graph may only have up to one null method node that represents all of
// the dynamic method invocations.
//
// Additionally, the 'root' node of a call graph represents the "entry point"
// node of the graph, which has an edge to every external method in the graph.
// This node has a null method pointer.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_CALLGRAPH_H
#define LLVM_ANALYSIS_CALLGRAPH_H
#include "llvm/Support/GraphTraits.h"
#include <map>
#include <vector>
class Method;
class Module;
namespace cfg {
class CallGraph;
class CallGraphNode {
Method *Meth;
vector<CallGraphNode*> CalledMethods;
CallGraphNode(const CallGraphNode &); // Do not implement
public:
typedef vector<CallGraphNode*>::iterator iterator;
typedef vector<CallGraphNode*>::const_iterator const_iterator;
// getMethod - Return the method that this call graph node represents...
Method *getMethod() const { return Meth; }
inline iterator begin() { return CalledMethods.begin(); }
inline iterator end() { return CalledMethods.end(); }
inline const_iterator begin() const { return CalledMethods.begin(); }
inline const_iterator end() const { return CalledMethods.end(); }
inline unsigned size() const { return CalledMethods.size(); }
inline CallGraphNode *operator[](unsigned i) const { return CalledMethods[i];}
void removeAllCalledMethods() {
CalledMethods.clear();
}
private: // Stuff to construct the node, used by CallGraph
friend class CallGraph;
// CallGraphNode ctor - Create a node for the specified method...
inline CallGraphNode(Method *M) : Meth(M) {}
// addCalledMethod add a method to the list of methods called by this one
void addCalledMethod(CallGraphNode *M) {
CalledMethods.push_back(M);
}
};
class CallGraph {
Module *Mod; // The module this call graph represents
typedef map<const Method *, CallGraphNode *> MethodMapTy;
MethodMapTy MethodMap; // Map from a method to its node
CallGraphNode *Root;
public:
CallGraph(Module *TheModule);
~CallGraph();
typedef MethodMapTy::iterator iterator;
typedef MethodMapTy::const_iterator const_iterator;
inline CallGraphNode *getRoot() { return Root; }
inline const CallGraphNode *getRoot() const { return Root; }
inline iterator begin() { return MethodMap.begin(); }
inline iterator end() { return MethodMap.end(); }
inline const_iterator begin() const { return MethodMap.begin(); }
inline const_iterator end() const { return MethodMap.end(); }
inline const CallGraphNode *operator[](const Method *M) const {
const_iterator I = MethodMap.find(M);
assert(I != MethodMap.end() && "Method not in callgraph!");
return I->second;
}
inline CallGraphNode *operator[](const Method *M) {
const_iterator I = MethodMap.find(M);
assert(I != MethodMap.end() && "Method not in callgraph!");
return I->second;
}
// Methods to keep a call graph up to date with a method that has been
// modified
//
void addMethodToModule(Method *Meth); // TODO IMPLEMENT
// removeMethodFromModule - Unlink the method from this module, returning it.
// Because this removes the method from the module, the call graph node is
// destroyed. This is only valid if the method does not call any other
// methods (ie, there are no edges in it's CGN). The easiest way to do this
// is to dropAllReferences before calling this.
//
Method *removeMethodFromModule(CallGraphNode *CGN);
Method *removeMethodFromModule(Method *Meth) {
return removeMethodFromModule((*this)[Meth]);
}
private: // Implementation of CallGraph construction
// getNodeFor - Return the node for the specified method or create one if it
// does not already exist.
//
CallGraphNode *getNodeFor(Method *M);
// addToCallGraph - Add a method to the call graph, and link the node to all
// of the methods that it calls.
//
void addToCallGraph(Method *M);
};
} // end namespace cfg
// Provide graph traits for tranversing call graphs using standard graph
// traversals.
template <> struct GraphTraits<cfg::CallGraphNode*> {
typedef cfg::CallGraphNode NodeType;
typedef NodeType::iterator ChildIteratorType;
static NodeType *getEntryNode(cfg::CallGraphNode *CGN) { return CGN; }
static inline ChildIteratorType child_begin(NodeType *N) { return N->begin();}
static inline ChildIteratorType child_end (NodeType *N) { return N->end(); }
};
template <> struct GraphTraits<const cfg::CallGraphNode*> {
typedef const cfg::CallGraphNode NodeType;
typedef NodeType::const_iterator ChildIteratorType;
static NodeType *getEntryNode(const cfg::CallGraphNode *CGN) { return CGN; }
static inline ChildIteratorType child_begin(NodeType *N) { return N->begin();}
static inline ChildIteratorType child_end (NodeType *N) { return N->end(); }
};
template<> struct GraphTraits<cfg::CallGraph*> :
public GraphTraits<cfg::CallGraphNode*> {
static NodeType *getEntryNode(cfg::CallGraph *CGN) {
return CGN->getRoot();
}
};
template<> struct GraphTraits<const cfg::CallGraph*> :
public GraphTraits<const cfg::CallGraphNode*> {
static NodeType *getEntryNode(const cfg::CallGraph *CGN) {
return CGN->getRoot();
}
};
// Checks if a method contains any call instructions.
// Note that this uses the call graph only if one is provided.
// It does not build the call graph.
//
bool isLeafMethod(const Method* method, const cfg::CallGraph *callGraph = 0);
#endif