RegionPass.h revision 255f89faee13dc491cb64fbeae3c763e7e2ea4e6 
1//===- RegionPass.h - RegionPass class ------------------------------------===//
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 defines the RegionPass class. All region based analysis,
11// optimization and transformation passes are derived from RegionPass.
12// This class is implemented following the some ideas of the LoopPass.h class.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_REGION_PASS_H
17#define LLVM_REGION_PASS_H
18
19#include "llvm/Analysis/RegionInfo.h"
20#include "llvm/Function.h"
21#include "llvm/Pass.h"
22#include "llvm/PassManagers.h"
23#include <deque>
24
25namespace llvm {
26
27class RGPassManager;
28class Function;
29
30//===----------------------------------------------------------------------===//
31/// @brief A pass that runs on each Region in a function.
32///
33/// RegionPass is managed by RGPassManager.
34class RegionPass : public Pass {
35public:
36  explicit RegionPass(char &pid) : Pass(PT_Region, pid) {}
37
38  //===--------------------------------------------------------------------===//
39  /// @name To be implemented by every RegionPass
40  ///
41  //@{
42  /// @brief Run the pass on a specific Region
43  ///
44  /// Accessing regions not contained in the current region is not allowed.
45  ///
46  /// @param R The region this pass is run on.
47  /// @param RGM The RegionPassManager that manages this Pass.
48  ///
49  /// @return True if the pass modifies this Region.
50  virtual bool runOnRegion(Region *R, RGPassManager &RGM) = 0;
51
52  /// @brief Get a pass to print the LLVM IR in the region.
53  ///
54  /// @param O      The ouput stream to print the Region.
55  /// @param Banner The banner to separate different printed passes.
56  ///
57  /// @return The pass to print the LLVM IR in the region.
58  Pass *createPrinterPass(raw_ostream &O, const std::string &Banner) const;
59
60  virtual bool doInitialization(Region *R, RGPassManager &RGM) { return false; }
61  virtual bool doFinalization() { return false; }
62  //@}
63
64  //===--------------------------------------------------------------------===//
65  /// @name PassManager API
66  ///
67  //@{
68  void preparePassManager(PMStack &PMS);
69
70  virtual void assignPassManager(PMStack &PMS,
71    PassManagerType PMT = PMT_RegionPassManager);
72
73  virtual PassManagerType getPotentialPassManagerType() const {
74    return PMT_RegionPassManager;
75  }
76  //@}
77};
78
79/// @brief The pass manager to schedule RegionPasses.
80class RGPassManager : public FunctionPass, public PMDataManager {
81  std::deque<Region*> RQ;
82  bool skipThisRegion;
83  bool redoThisRegion;
84  RegionInfo *RI;
85  Region *CurrentRegion;
86
87public:
88  static char ID;
89  explicit RGPassManager();
90
91  /// @brief Execute all of the passes scheduled for execution.
92  ///
93  /// @return True if any of the passes modifies the function.
94  bool runOnFunction(Function &F);
95
96  /// Pass Manager itself does not invalidate any analysis info.
97  /// RGPassManager needs RegionInfo.
98  void getAnalysisUsage(AnalysisUsage &Info) const;
99
100  virtual const char *getPassName() const {
101    return "Region Pass Manager";
102  }
103
104  virtual PMDataManager *getAsPMDataManager() { return this; }
105  virtual Pass *getAsPass() { return this; }
106
107  /// @brief Print passes managed by this manager.
108  void dumpPassStructure(unsigned Offset);
109
110  /// @brief Get passes contained by this manager.
111  Pass *getContainedPass(unsigned N) {
112    assert(N < PassVector.size() && "Pass number out of range!");
113    Pass *FP = static_cast<Pass *>(PassVector[N]);
114    return FP;
115  }
116
117  virtual PassManagerType getPassManagerType() const {
118    return PMT_RegionPassManager;
119  }
120};
121
122} // End llvm namespace
123
124#endif
125