llvm/lib/Analysis/IPA/DependenceGraph.cpp
2003-11-11 22:41:34 +00:00

88 lines
3.1 KiB
C++

//===- DependenceGraph.cpp - Dependence graph for a function ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements an explicit representation for the dependence graph
// of a function, with one node per instruction and one edge per dependence.
// Dependences include both data and control dependences.
//
// Each dep. graph node (class DepGraphNode) keeps lists of incoming and
// outgoing dependence edges.
//
// Each dep. graph edge (class Dependence) keeps a pointer to one end-point
// of the dependence. This saves space and is important because dep. graphs
// can grow quickly. It works just fine because the standard idiom is to
// start with a known node and enumerate the dependences to or from that node.
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/DependenceGraph.h"
#include "llvm/Function.h"
namespace llvm {
//----------------------------------------------------------------------------
// class Dependence:
//
// A representation of a simple (non-loop-related) dependence
//----------------------------------------------------------------------------
void Dependence::print(std::ostream &O) const
{
assert(depType != NoDependence && "This dependence should never be created!");
switch (depType) {
case TrueDependence: O << "TRUE dependence"; break;
case AntiDependence: O << "ANTI dependence"; break;
case OutputDependence: O << "OUTPUT dependence"; break;
case ControlDependence: O << "CONTROL dependence"; break;
default: assert(0 && "Invalid dependence type"); break;
}
}
//----------------------------------------------------------------------------
// class DepGraphNode
//----------------------------------------------------------------------------
void DepGraphNode::print(std::ostream &O) const
{
const_iterator DI = outDepBegin(), DE = outDepEnd();
O << "\nDeps. from instr:" << getInstr();
for ( ; DI != DE; ++DI)
{
O << "\t";
DI->print(O);
O << " to instruction:";
O << DI->getSink()->getInstr();
}
}
//----------------------------------------------------------------------------
// class DependenceGraph
//----------------------------------------------------------------------------
DependenceGraph::~DependenceGraph()
{
// Free all DepGraphNode objects created for this graph
for (map_iterator I = depNodeMap.begin(), E = depNodeMap.end(); I != E; ++I)
delete I->second;
}
void DependenceGraph::print(const Function& func, std::ostream &O) const
{
O << "DEPENDENCE GRAPH FOR FUNCTION " << func.getName() << ":\n";
for (Function::const_iterator BB=func.begin(), FE=func.end(); BB != FE; ++BB)
for (BasicBlock::const_iterator II=BB->begin(), IE=BB->end(); II !=IE; ++II)
if (const DepGraphNode* dgNode = this->getNode(*II))
dgNode->print(O);
}
} // End llvm namespace