--- /dev/null
+//===-- llvm/Support/DataFlow.h - dataflow as graphs ------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines specializations of GraphTraits that allows Use-Def and
+// Def-Use relations to be treated as proper graphs for generic algorithms.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_DATAFLOW_H
+#define LLVM_SUPPORT_DATAFLOW_H
+
+#include "llvm/User.h"
+#include "llvm/Value.h"
+#include "llvm/ADT/GraphTraits.h"
+
+namespace llvm {
+
+//===----------------------------------------------------------------------===//
+// Provide specializations of GraphTraits to be able to treat def-use/use-def
+// chains as graphs
+
+template <> struct GraphTraits<const User*> {
+ typedef const Value NodeType;
+ typedef Value::use_const_iterator ChildIteratorType;
+
+ static NodeType *getEntryNode(const User *G) {
+ return G;
+ }
+
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ return N->use_begin();
+ }
+
+ static inline ChildIteratorType child_end(NodeType *N) {
+ return N->use_end();
+ }
+};
+
+template <> struct GraphTraits<User*> {
+ typedef Value NodeType;
+ typedef Value::use_iterator ChildIteratorType;
+
+ static NodeType *getEntryNode(User *G) {
+ return G;
+ }
+
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ return N->use_begin();
+ }
+
+ static inline ChildIteratorType child_end(NodeType *N) {
+ return N->use_end();
+ }
+};
+
+template <> struct GraphTraits<Inverse<const User*> > {
+ typedef const Value NodeType;
+ typedef User::const_op_iterator ChildIteratorType;
+
+ static NodeType *getEntryNode(Inverse<const User*> G) {
+ return G.Graph;
+ }
+
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ if (const User *U = dyn_cast<User>(N))
+ return U->op_begin();
+ return NULL;
+ }
+
+ static inline ChildIteratorType child_end(NodeType *N) {
+ if(const User *U = dyn_cast<User>(N))
+ return U->op_end();
+ return NULL;
+ }
+};
+
+template <> struct GraphTraits<Inverse<User*> > {
+ typedef Value NodeType;
+ typedef User::op_iterator ChildIteratorType;
+
+ static NodeType *getEntryNode(Inverse<User*> G) {
+ return G.Graph;
+ }
+
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ if (User *U = dyn_cast<User>(N))
+ return U->op_begin();
+ return NULL;
+ }
+
+ static inline ChildIteratorType child_end(NodeType *N) {
+ if (User *U = dyn_cast<User>(N))
+ return U->op_end();
+ return NULL;
+ }
+};
+
+}
+#endif