llvm-6502/lib/CodeGen/PBQP/Graph.h
Lang Hames 030c4bfbc9 New PBQP solver.
* Fixed a reduction bug which occasionally led to infinite-cost (invalid)
  register allocation solutions despite the existence finite-cost solutions.
* Significantly reduced memory usage (>50% reduction).
* Simplified a lot of the solver code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94514 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-26 04:49:58 +00:00

358 lines
11 KiB
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//===-------------------- Graph.h - PBQP Graph ------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// PBQP Graph class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_PBQP_GRAPH_H
#define LLVM_CODEGEN_PBQP_GRAPH_H
#include "Math.h"
#include <list>
#include <vector>
namespace PBQP {
/// PBQP Graph class.
/// Instances of this class describe PBQP problems.
class Graph {
private:
// ----- TYPEDEFS -----
class NodeEntry;
class EdgeEntry;
typedef std::list<NodeEntry> NodeList;
typedef std::list<EdgeEntry> EdgeList;
public:
typedef NodeList::iterator NodeItr;
typedef EdgeList::iterator EdgeItr;
private:
typedef std::list<EdgeItr> AdjEdgeList;
public:
typedef AdjEdgeList::iterator AdjEdgeItr;
private:
class NodeEntry {
private:
Vector costs;
AdjEdgeList adjEdges;
unsigned degree;
void *data;
public:
NodeEntry(const Vector &costs) : costs(costs), degree(0) {}
Vector& getCosts() { return costs; }
unsigned getDegree() const { return degree; }
AdjEdgeItr edgesBegin() { return adjEdges.begin(); }
AdjEdgeItr edgesEnd() { return adjEdges.end(); }
AdjEdgeItr addEdge(EdgeItr e) {
++degree;
return adjEdges.insert(adjEdges.end(), e);
}
void removeEdge(AdjEdgeItr ae) {
--degree;
adjEdges.erase(ae);
}
void setData(void *data) { this->data = data; }
void* getData() { return data; }
};
class EdgeEntry {
private:
NodeItr node1, node2;
Matrix costs;
AdjEdgeItr node1AEItr, node2AEItr;
void *data;
public:
EdgeEntry(NodeItr node1, NodeItr node2, const Matrix &costs)
: node1(node1), node2(node2), costs(costs) {}
NodeItr getNode1() const { return node1; }
NodeItr getNode2() const { return node2; }
Matrix& getCosts() { return costs; }
void setNode1AEItr(AdjEdgeItr ae) { node1AEItr = ae; }
AdjEdgeItr getNode1AEItr() { return node1AEItr; }
void setNode2AEItr(AdjEdgeItr ae) { node2AEItr = ae; }
AdjEdgeItr getNode2AEItr() { return node2AEItr; }
void setData(void *data) { this->data = data; }
void *getData() { return data; }
};
// ----- MEMBERS -----
NodeList nodes;
unsigned numNodes;
EdgeList edges;
unsigned numEdges;
// ----- INTERNAL METHODS -----
NodeEntry& getNode(NodeItr nItr) { return *nItr; }
const NodeEntry& getNode(NodeItr nItr) const { return *nItr; }
EdgeEntry& getEdge(EdgeItr eItr) { return *eItr; }
const EdgeEntry& getEdge(EdgeItr eItr) const { return *eItr; }
NodeItr addConstructedNode(const NodeEntry &n) {
++numNodes;
return nodes.insert(nodes.end(), n);
}
EdgeItr addConstructedEdge(const EdgeEntry &e) {
assert(findEdge(e.getNode1(), e.getNode2()) == edges.end() &&
"Attempt to add duplicate edge.");
++numEdges;
EdgeItr edgeItr = edges.insert(edges.end(), e);
EdgeEntry &ne = getEdge(edgeItr);
NodeEntry &n1 = getNode(ne.getNode1());
NodeEntry &n2 = getNode(ne.getNode2());
// Sanity check on matrix dimensions:
assert((n1.getCosts().getLength() == ne.getCosts().getRows()) &&
(n2.getCosts().getLength() == ne.getCosts().getCols()) &&
"Edge cost dimensions do not match node costs dimensions.");
ne.setNode1AEItr(n1.addEdge(edgeItr));
ne.setNode2AEItr(n2.addEdge(edgeItr));
return edgeItr;
}
public:
Graph() : numNodes(0), numEdges(0) {}
/// \brief Add a node with the given costs.
/// @param costs Cost vector for the new node.
/// @return Node iterator for the added node.
NodeItr addNode(const Vector &costs) {
return addConstructedNode(NodeEntry(costs));
}
/// \brief Add an edge between the given nodes with the given costs.
/// @param n1Itr First node.
/// @param n2Itr Second node.
/// @return Edge iterator for the added edge.
EdgeItr addEdge(Graph::NodeItr n1Itr, Graph::NodeItr n2Itr,
const Matrix &costs) {
assert(getNodeCosts(n1Itr).getLength() == costs.getRows() &&
getNodeCosts(n2Itr).getLength() == costs.getCols() &&
"Matrix dimensions mismatch.");
return addConstructedEdge(EdgeEntry(n1Itr, n2Itr, costs));
}
/// \brief Get the number of nodes in the graph.
/// @return Number of nodes in the graph.
unsigned getNumNodes() const { return numNodes; }
/// \brief Get the number of edges in the graph.
/// @return Number of edges in the graph.
unsigned getNumEdges() const { return numEdges; }
/// \brief Get a node's cost vector.
/// @param nItr Node iterator.
/// @return Node cost vector.
Vector& getNodeCosts(NodeItr nItr) { return getNode(nItr).getCosts(); }
/// \brief Set a node's data pointer.
/// @param nItr Node iterator.
/// @param data Pointer to node data.
///
/// Typically used by a PBQP solver to attach data to aid in solution.
void setNodeData(NodeItr nItr, void *data) { getNode(nItr).setData(data); }
/// \brief Get the node's data pointer.
/// @param nItr Node iterator.
/// @return Pointer to node data.
void* getNodeData(NodeItr nItr) { return getNode(nItr).getData(); }
/// \brief Get an edge's cost matrix.
/// @param eItr Edge iterator.
/// @return Edge cost matrix.
Matrix& getEdgeCosts(EdgeItr eItr) { return getEdge(eItr).getCosts(); }
/// \brief Set an edge's data pointer.
/// @param eItr Edge iterator.
/// @param data Pointer to edge data.
///
/// Typically used by a PBQP solver to attach data to aid in solution.
void setEdgeData(EdgeItr eItr, void *data) { getEdge(eItr).setData(data); }
/// \brief Get an edge's data pointer.
/// @param eItr Edge iterator.
/// @return Pointer to edge data.
void* getEdgeData(EdgeItr eItr) { return getEdge(eItr).getData(); }
/// \brief Get a node's degree.
/// @param nItr Node iterator.
/// @return The degree of the node.
unsigned getNodeDegree(NodeItr nItr) const {
return getNode(nItr).getDegree();
}
/// \brief Begin iterator for node set.
NodeItr nodesBegin() { return nodes.begin(); }
/// \brief End iterator for node set.
NodeItr nodesEnd() { return nodes.end(); }
/// \brief Begin iterator for edge set.
EdgeItr edgesBegin() { return edges.begin(); }
/// \brief End iterator for edge set.
EdgeItr edgesEnd() { return edges.end(); }
/// \brief Get begin iterator for adjacent edge set.
/// @param nItr Node iterator.
/// @return Begin iterator for the set of edges connected to the given node.
AdjEdgeItr adjEdgesBegin(NodeItr nItr) {
return getNode(nItr).edgesBegin();
}
/// \brief Get end iterator for adjacent edge set.
/// @param nItr Node iterator.
/// @return End iterator for the set of edges connected to the given node.
AdjEdgeItr adjEdgesEnd(NodeItr nItr) {
return getNode(nItr).edgesEnd();
}
/// \brief Get the first node connected to this edge.
/// @param eItr Edge iterator.
/// @return The first node connected to the given edge.
NodeItr getEdgeNode1(EdgeItr eItr) {
return getEdge(eItr).getNode1();
}
/// \brief Get the second node connected to this edge.
/// @param eItr Edge iterator.
/// @return The second node connected to the given edge.
NodeItr getEdgeNode2(EdgeItr eItr) {
return getEdge(eItr).getNode2();
}
/// \brief Get the "other" node connected to this edge.
/// @param eItr Edge iterator.
/// @param nItr Node iterator for the "given" node.
/// @return The iterator for the "other" node connected to this edge.
NodeItr getEdgeOtherNode(EdgeItr eItr, NodeItr nItr) {
EdgeEntry &e = getEdge(eItr);
if (e.getNode1() == nItr) {
return e.getNode2();
} // else
return e.getNode1();
}
/// \brief Get the edge connecting two nodes.
/// @param n1Itr First node iterator.
/// @param n2Itr Second node iterator.
/// @return An iterator for edge (n1Itr, n2Itr) if such an edge exists,
/// otherwise returns edgesEnd().
EdgeItr findEdge(NodeItr n1Itr, NodeItr n2Itr) {
for (AdjEdgeItr aeItr = adjEdgesBegin(n1Itr), aeEnd = adjEdgesEnd(n1Itr);
aeItr != aeEnd; ++aeItr) {
if ((getEdgeNode1(*aeItr) == n2Itr) ||
(getEdgeNode2(*aeItr) == n2Itr)) {
return *aeItr;
}
}
return edges.end();
}
/// \brief Remove a node from the graph.
/// @param nItr Node iterator.
void removeNode(NodeItr nItr) {
NodeEntry &n = getNode(nItr);
for (AdjEdgeItr itr = n.edgesBegin(), end = n.edgesEnd(); itr != end;) {
EdgeItr eItr = *itr;
++itr;
removeEdge(eItr);
}
nodes.erase(nItr);
--numNodes;
}
/// \brief Remove an edge from the graph.
/// @param eItr Edge iterator.
void removeEdge(EdgeItr eItr) {
EdgeEntry &e = getEdge(eItr);
NodeEntry &n1 = getNode(e.getNode1());
NodeEntry &n2 = getNode(e.getNode2());
n1.removeEdge(e.getNode1AEItr());
n2.removeEdge(e.getNode2AEItr());
edges.erase(eItr);
--numEdges;
}
/// \brief Remove all nodes and edges from the graph.
void clear() {
nodes.clear();
edges.clear();
numNodes = numEdges = 0;
}
/// \brief Print a representation of this graph in DOT format.
/// @param os Output stream to print on.
template <typename OStream>
void printDot(OStream &os) {
os << "graph {\n";
for (NodeItr nodeItr = nodesBegin(), nodeEnd = nodesEnd();
nodeItr != nodeEnd; ++nodeItr) {
os << " node" << nodeItr << " [ label=\""
<< nodeItr << ": " << getNodeCosts(nodeItr) << "\" ]\n";
}
os << " edge [ len=" << getNumNodes() << " ]\n";
for (EdgeItr edgeItr = edgesBegin(), edgeEnd = edgesEnd();
edgeItr != edgeEnd; ++edgeItr) {
os << " node" << getEdgeNode1(edgeItr)
<< " -- node" << getEdgeNode2(edgeItr)
<< " [ label=\"";
const Matrix &edgeCosts = getEdgeCosts(edgeItr);
for (unsigned i = 0; i < edgeCosts.getRows(); ++i) {
os << edgeCosts.getRowAsVector(i) << "\\n";
}
os << "\" ]\n";
}
os << "}\n";
}
};
class NodeItrComparator {
public:
bool operator()(Graph::NodeItr n1, Graph::NodeItr n2) const {
return &*n1 < &*n2;
}
};
class EdgeItrCompartor {
public:
bool operator()(Graph::EdgeItr e1, Graph::EdgeItr e2) const {
return &*e1 < &*e2;
}
};
}
#endif // LLVM_CODEGEN_PBQP_GRAPH_HPP