llvm-project/clang/lib/Analysis/CallGraph.cpp

149 lines
3.7 KiB
C++

//== CallGraph.cpp - Call graph building ------------------------*- C++ -*--==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defined the CallGraph and CGBuilder classes.
//
//===----------------------------------------------------------------------===//
#include "clang/Analysis/CallGraph.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/StmtVisitor.h"
#include "llvm/Support/GraphWriter.h"
using namespace clang;
using namespace idx;
namespace {
class CGBuilder : public StmtVisitor<CGBuilder> {
CallGraph &G;
FunctionDecl *FD;
Entity CallerEnt;
CallGraphNode *CallerNode;
public:
CGBuilder(CallGraph &g, FunctionDecl *fd, Entity E, CallGraphNode *N)
: G(g), FD(fd), CallerEnt(E), CallerNode(N) {}
void VisitStmt(Stmt *S) { VisitChildren(S); }
void VisitCallExpr(CallExpr *CE);
void VisitChildren(Stmt *S) {
for (Stmt::child_iterator I=S->child_begin(), E=S->child_end(); I != E;++I)
if (*I)
static_cast<CGBuilder*>(this)->Visit(*I);
}
};
}
void CGBuilder::VisitCallExpr(CallExpr *CE) {
if (FunctionDecl *CalleeDecl = CE->getDirectCallee()) {
Entity Ent = Entity::get(CalleeDecl, G.getProgram());
CallGraphNode *CalleeNode = G.getOrInsertFunction(Ent);
CallerNode->addCallee(ASTLocation(FD, CE), CalleeNode);
}
}
CallGraph::CallGraph() : Root(0) {
ExternalCallingNode = getOrInsertFunction(Entity());
}
CallGraph::~CallGraph() {
if (!FunctionMap.empty()) {
for (FunctionMapTy::iterator I = FunctionMap.begin(), E = FunctionMap.end();
I != E; ++I)
delete I->second;
FunctionMap.clear();
}
}
void CallGraph::addTU(ASTContext& Ctx) {
DeclContext *DC = Ctx.getTranslationUnitDecl();
for (DeclContext::decl_iterator I = DC->decls_begin(), E = DC->decls_end();
I != E; ++I) {
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) {
if (FD->isThisDeclarationADefinition()) {
// Set caller's ASTContext.
Entity Ent = Entity::get(FD, Prog);
CallGraphNode *Node = getOrInsertFunction(Ent);
CallerCtx[Node] = &Ctx;
// If this function has external linkage, anything could call it.
if (FD->isGlobal())
ExternalCallingNode->addCallee(idx::ASTLocation(), Node);
// Set root node to 'main' function.
if (FD->getNameAsString() == "main")
Root = Node;
CGBuilder builder(*this, FD, Ent, Node);
builder.Visit(FD->getBody());
}
}
}
}
CallGraphNode *CallGraph::getOrInsertFunction(Entity F) {
CallGraphNode *&Node = FunctionMap[F];
if (Node)
return Node;
return Node = new CallGraphNode(F);
}
Decl *CallGraph::getDecl(CallGraphNode *Node) {
// Get the function's context.
ASTContext *Ctx = CallerCtx[Node];
return Node->getDecl(*Ctx);
}
void CallGraph::print(llvm::raw_ostream &os) {
for (iterator I = begin(), E = end(); I != E; ++I) {
if (I->second->hasCallee()) {
os << "function: " << I->first.getPrintableName()
<< " calls:\n";
for (CallGraphNode::iterator CI = I->second->begin(),
CE = I->second->end(); CI != CE; ++CI) {
os << " " << CI->second->getName();
}
os << '\n';
}
}
}
void CallGraph::dump() {
print(llvm::errs());
}
void CallGraph::ViewCallGraph() const {
llvm::ViewGraph(*this, "CallGraph");
}
namespace llvm {
template <>
struct DOTGraphTraits<CallGraph> : public DefaultDOTGraphTraits {
static std::string getNodeLabel(const CallGraphNode *Node,
const CallGraph &CG, bool ShortNames) {
return Node->getName();
}
};
}