1 | //===- RegionPass.h - RegionPass class --------------------------*- C++ -*-===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // This file defines the RegionPass class. All region based analysis, |
10 | // optimization and transformation passes are derived from RegionPass. |
11 | // This class is implemented following the some ideas of the LoopPass.h class. |
12 | // |
13 | //===----------------------------------------------------------------------===// |
14 | |
15 | #ifndef LLVM_ANALYSIS_REGIONPASS_H |
16 | #define LLVM_ANALYSIS_REGIONPASS_H |
17 | |
18 | #include "llvm/IR/LegacyPassManagers.h" |
19 | #include "llvm/Pass.h" |
20 | #include <deque> |
21 | |
22 | namespace llvm { |
23 | class Function; |
24 | class RGPassManager; |
25 | class Region; |
26 | class RegionInfo; |
27 | |
28 | //===----------------------------------------------------------------------===// |
29 | /// A pass that runs on each Region in a function. |
30 | /// |
31 | /// RegionPass is managed by RGPassManager. |
32 | class RegionPass : public Pass { |
33 | public: |
34 | explicit RegionPass(char &pid) : Pass(PT_Region, pid) {} |
35 | |
36 | //===--------------------------------------------------------------------===// |
37 | /// @name To be implemented by every RegionPass |
38 | /// |
39 | //@{ |
40 | /// Run the pass on a specific Region |
41 | /// |
42 | /// Accessing regions not contained in the current region is not allowed. |
43 | /// |
44 | /// @param R The region this pass is run on. |
45 | /// @param RGM The RegionPassManager that manages this Pass. |
46 | /// |
47 | /// @return True if the pass modifies this Region. |
48 | virtual bool runOnRegion(Region *R, RGPassManager &RGM) = 0; |
49 | |
50 | /// Get a pass to print the LLVM IR in the region. |
51 | /// |
52 | /// @param O The output stream to print the Region. |
53 | /// @param Banner The banner to separate different printed passes. |
54 | /// |
55 | /// @return The pass to print the LLVM IR in the region. |
56 | Pass *createPrinterPass(raw_ostream &O, |
57 | const std::string &Banner) const override; |
58 | |
59 | using llvm::Pass::doInitialization; |
60 | using llvm::Pass::doFinalization; |
61 | |
62 | virtual bool doInitialization(Region *R, RGPassManager &RGM) { return false; } |
63 | virtual bool doFinalization() { return false; } |
64 | //@} |
65 | |
66 | //===--------------------------------------------------------------------===// |
67 | /// @name PassManager API |
68 | /// |
69 | //@{ |
70 | void preparePassManager(PMStack &PMS) override; |
71 | |
72 | void assignPassManager(PMStack &PMS, |
73 | PassManagerType PMT = PMT_RegionPassManager) override; |
74 | |
75 | PassManagerType getPotentialPassManagerType() const override { |
76 | return PMT_RegionPassManager; |
77 | } |
78 | //@} |
79 | |
80 | protected: |
81 | /// Optional passes call this function to check whether the pass should be |
82 | /// skipped. This is the case when optimization bisect is over the limit. |
83 | bool skipRegion(Region &R) const; |
84 | }; |
85 | |
86 | /// The pass manager to schedule RegionPasses. |
87 | class RGPassManager : public FunctionPass, public PMDataManager { |
88 | std::deque<Region*> RQ; |
89 | RegionInfo *RI; |
90 | Region *CurrentRegion; |
91 | |
92 | public: |
93 | static char ID; |
94 | explicit RGPassManager(); |
95 | |
96 | /// Execute all of the passes scheduled for execution. |
97 | /// |
98 | /// @return True if any of the passes modifies the function. |
99 | bool runOnFunction(Function &F) override; |
100 | |
101 | /// Pass Manager itself does not invalidate any analysis info. |
102 | /// RGPassManager needs RegionInfo. |
103 | void getAnalysisUsage(AnalysisUsage &Info) const override; |
104 | |
105 | StringRef getPassName() const override { return "Region Pass Manager" ; } |
106 | |
107 | PMDataManager *getAsPMDataManager() override { return this; } |
108 | Pass *getAsPass() override { return this; } |
109 | |
110 | /// Print passes managed by this manager. |
111 | void dumpPassStructure(unsigned Offset) override; |
112 | |
113 | /// Get passes contained by this manager. |
114 | Pass *getContainedPass(unsigned N) { |
115 | assert(N < PassVector.size() && "Pass number out of range!" ); |
116 | Pass *FP = static_cast<Pass *>(PassVector[N]); |
117 | return FP; |
118 | } |
119 | |
120 | PassManagerType getPassManagerType() const override { |
121 | return PMT_RegionPassManager; |
122 | } |
123 | }; |
124 | |
125 | } // End llvm namespace |
126 | |
127 | #endif |
128 | |