llvm-6502/lib/Analysis/IPA/CallGraph.cpp
Chandler Carruth 0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00

339 lines
12 KiB
C++

//===- CallGraph.cpp - Build a Module's call graph ------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the CallGraph class and provides the BasicCallGraph
// default implementation.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/CallGraph.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
namespace {
//===----------------------------------------------------------------------===//
// BasicCallGraph class definition
//
class BasicCallGraph : public ModulePass, public CallGraph {
// Root is root of the call graph, or the external node if a 'main' function
// couldn't be found.
//
CallGraphNode *Root;
// ExternalCallingNode - This node has edges to all external functions and
// those internal functions that have their address taken.
CallGraphNode *ExternalCallingNode;
// CallsExternalNode - This node has edges to it from all functions making
// indirect calls or calling an external function.
CallGraphNode *CallsExternalNode;
public:
static char ID; // Class identification, replacement for typeinfo
BasicCallGraph() : ModulePass(ID), Root(0),
ExternalCallingNode(0), CallsExternalNode(0) {
initializeBasicCallGraphPass(*PassRegistry::getPassRegistry());
}
// runOnModule - Compute the call graph for the specified module.
virtual bool runOnModule(Module &M) {
CallGraph::initialize(M);
ExternalCallingNode = getOrInsertFunction(0);
CallsExternalNode = new CallGraphNode(0);
Root = 0;
// Add every function to the call graph.
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
addToCallGraph(I);
// If we didn't find a main function, use the external call graph node
if (Root == 0) Root = ExternalCallingNode;
return false;
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
virtual void print(raw_ostream &OS, const Module *) const {
OS << "CallGraph Root is: ";
if (Function *F = getRoot()->getFunction())
OS << F->getName() << "\n";
else {
OS << "<<null function: 0x" << getRoot() << ">>\n";
}
CallGraph::print(OS, 0);
}
virtual void releaseMemory() {
destroy();
}
/// getAdjustedAnalysisPointer - This method is used when a pass implements
/// an analysis interface through multiple inheritance. If needed, it should
/// override this to adjust the this pointer as needed for the specified pass
/// info.
virtual void *getAdjustedAnalysisPointer(AnalysisID PI) {
if (PI == &CallGraph::ID)
return (CallGraph*)this;
return this;
}
CallGraphNode* getExternalCallingNode() const { return ExternalCallingNode; }
CallGraphNode* getCallsExternalNode() const { return CallsExternalNode; }
// getRoot - Return the root of the call graph, which is either main, or if
// main cannot be found, the external node.
//
CallGraphNode *getRoot() { return Root; }
const CallGraphNode *getRoot() const { return Root; }
private:
//===---------------------------------------------------------------------
// Implementation of CallGraph construction
//
// addToCallGraph - Add a function to the call graph, and link the node to all
// of the functions that it calls.
//
void addToCallGraph(Function *F) {
CallGraphNode *Node = getOrInsertFunction(F);
// If this function has external linkage, anything could call it.
if (!F->hasLocalLinkage()) {
ExternalCallingNode->addCalledFunction(CallSite(), Node);
// Found the entry point?
if (F->getName() == "main") {
if (Root) // Found multiple external mains? Don't pick one.
Root = ExternalCallingNode;
else
Root = Node; // Found a main, keep track of it!
}
}
// If this function has its address taken, anything could call it.
if (F->hasAddressTaken())
ExternalCallingNode->addCalledFunction(CallSite(), Node);
// If this function is not defined in this translation unit, it could call
// anything.
if (F->isDeclaration() && !F->isIntrinsic())
Node->addCalledFunction(CallSite(), CallsExternalNode);
// Look for calls by this function.
for (Function::iterator BB = F->begin(), BBE = F->end(); BB != BBE; ++BB)
for (BasicBlock::iterator II = BB->begin(), IE = BB->end();
II != IE; ++II) {
CallSite CS(cast<Value>(II));
if (CS) {
const Function *Callee = CS.getCalledFunction();
if (!Callee)
// Indirect calls of intrinsics are not allowed so no need to check.
Node->addCalledFunction(CS, CallsExternalNode);
else if (!Callee->isIntrinsic())
Node->addCalledFunction(CS, getOrInsertFunction(Callee));
}
}
}
//
// destroy - Release memory for the call graph
virtual void destroy() {
/// CallsExternalNode is not in the function map, delete it explicitly.
if (CallsExternalNode) {
CallsExternalNode->allReferencesDropped();
delete CallsExternalNode;
CallsExternalNode = 0;
}
CallGraph::destroy();
}
};
} //End anonymous namespace
INITIALIZE_ANALYSIS_GROUP(CallGraph, "Call Graph", BasicCallGraph)
INITIALIZE_AG_PASS(BasicCallGraph, CallGraph, "basiccg",
"Basic CallGraph Construction", false, true, true)
char CallGraph::ID = 0;
char BasicCallGraph::ID = 0;
void CallGraph::initialize(Module &M) {
Mod = &M;
}
void CallGraph::destroy() {
if (FunctionMap.empty()) return;
// Reset all node's use counts to zero before deleting them to prevent an
// assertion from firing.
#ifndef NDEBUG
for (FunctionMapTy::iterator I = FunctionMap.begin(), E = FunctionMap.end();
I != E; ++I)
I->second->allReferencesDropped();
#endif
for (FunctionMapTy::iterator I = FunctionMap.begin(), E = FunctionMap.end();
I != E; ++I)
delete I->second;
FunctionMap.clear();
}
void CallGraph::print(raw_ostream &OS, Module*) const {
for (CallGraph::const_iterator I = begin(), E = end(); I != E; ++I)
I->second->print(OS);
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void CallGraph::dump() const {
print(dbgs(), 0);
}
#endif
//===----------------------------------------------------------------------===//
// Implementations of public modification methods
//
// removeFunctionFromModule - 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 *CallGraph::removeFunctionFromModule(CallGraphNode *CGN) {
assert(CGN->empty() && "Cannot remove function from call "
"graph if it references other functions!");
Function *F = CGN->getFunction(); // Get the function for the call graph node
delete CGN; // Delete the call graph node for this func
FunctionMap.erase(F); // Remove the call graph node from the map
Mod->getFunctionList().remove(F);
return F;
}
/// spliceFunction - Replace the function represented by this node by another.
/// This does not rescan the body of the function, so it is suitable when
/// splicing the body of the old function to the new while also updating all
/// callers from old to new.
///
void CallGraph::spliceFunction(const Function *From, const Function *To) {
assert(FunctionMap.count(From) && "No CallGraphNode for function!");
assert(!FunctionMap.count(To) &&
"Pointing CallGraphNode at a function that already exists");
FunctionMapTy::iterator I = FunctionMap.find(From);
I->second->F = const_cast<Function*>(To);
FunctionMap[To] = I->second;
FunctionMap.erase(I);
}
// getOrInsertFunction - This method is identical to calling operator[], but
// it will insert a new CallGraphNode for the specified function if one does
// not already exist.
CallGraphNode *CallGraph::getOrInsertFunction(const Function *F) {
CallGraphNode *&CGN = FunctionMap[F];
if (CGN) return CGN;
assert((!F || F->getParent() == Mod) && "Function not in current module!");
return CGN = new CallGraphNode(const_cast<Function*>(F));
}
void CallGraphNode::print(raw_ostream &OS) const {
if (Function *F = getFunction())
OS << "Call graph node for function: '" << F->getName() << "'";
else
OS << "Call graph node <<null function>>";
OS << "<<" << this << ">> #uses=" << getNumReferences() << '\n';
for (const_iterator I = begin(), E = end(); I != E; ++I) {
OS << " CS<" << I->first << "> calls ";
if (Function *FI = I->second->getFunction())
OS << "function '" << FI->getName() <<"'\n";
else
OS << "external node\n";
}
OS << '\n';
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void CallGraphNode::dump() const { print(dbgs()); }
#endif
/// removeCallEdgeFor - This method removes the edge in the node for the
/// specified call site. Note that this method takes linear time, so it
/// should be used sparingly.
void CallGraphNode::removeCallEdgeFor(CallSite CS) {
for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
assert(I != CalledFunctions.end() && "Cannot find callsite to remove!");
if (I->first == CS.getInstruction()) {
I->second->DropRef();
*I = CalledFunctions.back();
CalledFunctions.pop_back();
return;
}
}
}
// removeAnyCallEdgeTo - This method removes any call edges from this node to
// the specified callee function. This takes more time to execute than
// removeCallEdgeTo, so it should not be used unless necessary.
void CallGraphNode::removeAnyCallEdgeTo(CallGraphNode *Callee) {
for (unsigned i = 0, e = CalledFunctions.size(); i != e; ++i)
if (CalledFunctions[i].second == Callee) {
Callee->DropRef();
CalledFunctions[i] = CalledFunctions.back();
CalledFunctions.pop_back();
--i; --e;
}
}
/// removeOneAbstractEdgeTo - Remove one edge associated with a null callsite
/// from this node to the specified callee function.
void CallGraphNode::removeOneAbstractEdgeTo(CallGraphNode *Callee) {
for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
assert(I != CalledFunctions.end() && "Cannot find callee to remove!");
CallRecord &CR = *I;
if (CR.second == Callee && CR.first == 0) {
Callee->DropRef();
*I = CalledFunctions.back();
CalledFunctions.pop_back();
return;
}
}
}
/// replaceCallEdge - This method replaces the edge in the node for the
/// specified call site with a new one. Note that this method takes linear
/// time, so it should be used sparingly.
void CallGraphNode::replaceCallEdge(CallSite CS,
CallSite NewCS, CallGraphNode *NewNode){
for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
assert(I != CalledFunctions.end() && "Cannot find callsite to remove!");
if (I->first == CS.getInstruction()) {
I->second->DropRef();
I->first = NewCS.getInstruction();
I->second = NewNode;
NewNode->AddRef();
return;
}
}
}
// Enuse that users of CallGraph.h also link with this file
DEFINING_FILE_FOR(CallGraph)