1 files changed, 54 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/SDNodeOrdering.h b/lib/CodeGen/SelectionDAG/SDNodeOrdering.h
new file mode 100644
index 000000000000..f88b26d5c422
--- /dev/null
+++ b/lib/CodeGen/SelectionDAG/SDNodeOrdering.h
@@ -0,0 +1,54 @@
+//===-- llvm/CodeGen/SDNodeOrdering.h - SDNode Ordering ---------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the SDNodeOrdering class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_SDNODEORDERING_H
+#define LLVM_CODEGEN_SDNODEORDERING_H
+
+#include "llvm/ADT/DenseMap.h"
+
+namespace llvm {
+
+class SDNode;
+
+/// SDNodeOrdering - Maps a unique (monotonically increasing) value to each
+/// SDNode that roughly corresponds to the ordering of the original LLVM
+/// instruction. This is used for turning off scheduling, because we'll forgo
+/// the normal scheduling algorithms and output the instructions according to
+/// this ordering.
+class SDNodeOrdering {
+  DenseMap<const SDNode*, unsigned> OrderMap;
+
+  void operator=(const SDNodeOrdering&);   // Do not implement.
+  SDNodeOrdering(const SDNodeOrdering&);   // Do not implement.
+public:
+  SDNodeOrdering() {}
+
+  void add(const SDNode *Node, unsigned O) {
+    OrderMap[Node] = O;
+  }
+  void remove(const SDNode *Node) {
+    DenseMap<const SDNode*, unsigned>::iterator Itr = OrderMap.find(Node);
+    if (Itr != OrderMap.end())
+      OrderMap.erase(Itr);
+  }
+  void clear() {
+    OrderMap.clear();
+  }
+  unsigned getOrder(const SDNode *Node) {
+    return OrderMap[Node];
+  }
+};
+
+} // end llvm namespace
+
+#endif