SDNodeOrdering.h revision e264f62ca09a8f65c87a46d562a4d0f9ec5d457e 
1//===-- llvm/CodeGen/SDNodeOrdering.h - SDNode Ordering ---------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file declares the SDNodeOrdering class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CODEGEN_SDNODEORDERING_H
15#define LLVM_CODEGEN_SDNODEORDERING_H
16
17#include "llvm/ADT/DenseMap.h"
18
19namespace llvm {
20
21class SDNode;
22
23/// SDNodeOrdering - Maps a unique (monotonically increasing) value to each
24/// SDNode that roughly corresponds to the ordering of the original LLVM
25/// instruction. This is used for turning off scheduling, because we'll forgo
26/// the normal scheduling algorithms and output the instructions according to
27/// this ordering.
28class SDNodeOrdering {
29  DenseMap<const SDNode*, unsigned> OrderMap;
30
31  void operator=(const SDNodeOrdering&);   // Do not implement.
32  SDNodeOrdering(const SDNodeOrdering&);   // Do not implement.
33public:
34  SDNodeOrdering() {}
35
36  void add(const SDNode *Node, unsigned O) {
37    OrderMap[Node] = O;
38  }
39  void remove(const SDNode *Node) {
40    DenseMap<const SDNode*, unsigned>::iterator Itr = OrderMap.find(Node);
41    if (Itr != OrderMap.end())
42      OrderMap.erase(Itr);
43  }
44  void clear() {
45    OrderMap.clear();
46  }
47  unsigned getOrder(const SDNode *Node) {
48    return OrderMap[Node];
49  }
50};
51
52} // end llvm namespace
53
54#endif
55