EdgeBundles.h revision 221345 
1//===-------- EdgeBundles.h - Bundles of CFG edges --------------*- 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// The EdgeBundles analysis forms equivalence classes of CFG edges such that all
11// edges leaving a machine basic block are in the same bundle, and all edges
12// leaving a basic block are in the same bundle.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_CODEGEN_EDGEBUNDLES_H
17#define LLVM_CODEGEN_EDGEBUNDLES_H
18
19#include "llvm/ADT/ArrayRef.h"
20#include "llvm/ADT/IntEqClasses.h"
21#include "llvm/CodeGen/MachineFunctionPass.h"
22
23namespace llvm {
24
25class EdgeBundles : public MachineFunctionPass {
26  const MachineFunction *MF;
27
28  /// EC - Each edge bundle is an equivalence class. The keys are:
29  ///   2*BB->getNumber()   -> Ingoing bundle.
30  ///   2*BB->getNumber()+1 -> Outgoing bundle.
31  IntEqClasses EC;
32
33  /// Blocks - Map each bundle to a list of basic block numbers.
34  SmallVector<SmallVector<unsigned, 8>, 4> Blocks;
35
36public:
37  static char ID;
38  EdgeBundles() : MachineFunctionPass(ID) {}
39
40  /// getBundle - Return the ingoing (Out = false) or outgoing (Out = true)
41  /// bundle number for basic block #N
42  unsigned getBundle(unsigned N, bool Out) const { return EC[2 * N + Out]; }
43
44  /// getNumBundles - Return the total number of bundles in the CFG.
45  unsigned getNumBundles() const { return EC.getNumClasses(); }
46
47  /// getBlocks - Return an array of blocks that are connected to Bundle.
48  ArrayRef<unsigned> getBlocks(unsigned Bundle) { return Blocks[Bundle]; }
49
50  /// getMachineFunction - Return the last machine function computed.
51  const MachineFunction *getMachineFunction() const { return MF; }
52
53  /// view - Visualize the annotated bipartite CFG with Graphviz.
54  void view() const;
55
56private:
57  virtual bool runOnMachineFunction(MachineFunction&);
58  virtual void getAnalysisUsage(AnalysisUsage&) const;
59};
60
61/// Specialize WriteGraph, the standard implementation won't work.
62raw_ostream &WriteGraph(raw_ostream &O, const EdgeBundles &G,
63                        bool ShortNames = false,
64                        const std::string &Title = "");
65
66} // end namespace llvm
67
68#endif
69