1 //===- LoopPass.h - LoopPass class ----------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines LoopPass class. All loop optimization
11 // and transformation passes are derived from LoopPass.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_LOOP_PASS_H
16 #define LLVM_LOOP_PASS_H
18 #include "llvm/Analysis/LoopInfo.h"
19 #include "llvm/Pass.h"
20 #include "llvm/PassManagers.h"
21 #include "llvm/Function.h"
29 class LoopPass : public Pass {
31 explicit LoopPass(intptr_t pid) : Pass(PT_Loop, pid) {}
32 explicit LoopPass(void *pid) : Pass(PT_Loop, pid) {}
34 /// getPrinterPass - Get a pass to print the function corresponding
36 Pass *createPrinterPass(raw_ostream &O, const std::string &Banner) const;
38 // runOnLoop - This method should be implemented by the subclass to perform
39 // whatever action is necessary for the specified Loop.
40 virtual bool runOnLoop(Loop *L, LPPassManager &LPM) = 0;
42 // Initialization and finalization hooks.
43 virtual bool doInitialization(Loop *L, LPPassManager &LPM) {
47 // Finalization hook does not supply Loop because at this time
48 // loop nest is completely different.
49 virtual bool doFinalization() { return false; }
51 // Check if this pass is suitable for the current LPPassManager, if
52 // available. This pass P is not suitable for a LPPassManager if P
53 // is not preserving higher level analysis info used by other
54 // LPPassManager passes. In such case, pop LPPassManager from the
55 // stack. This will force assignPassManager() to create new
56 // LPPassManger as expected.
57 void preparePassManager(PMStack &PMS);
59 /// Assign pass manager to manage this pass
60 virtual void assignPassManager(PMStack &PMS,
61 PassManagerType PMT = PMT_LoopPassManager);
63 /// Return what kind of Pass Manager can manage this pass.
64 virtual PassManagerType getPotentialPassManagerType() const {
65 return PMT_LoopPassManager;
68 //===--------------------------------------------------------------------===//
69 /// SimpleAnalysis - Provides simple interface to update analysis info
70 /// maintained by various passes. Note, if required this interface can
71 /// be extracted into a separate abstract class but it would require
72 /// additional use of multiple inheritance in Pass class hierarchy, something
73 /// we are trying to avoid.
75 /// Each loop pass can override these simple analysis hooks to update
76 /// desired analysis information.
77 /// cloneBasicBlockAnalysis - Clone analysis info associated with basic block.
78 virtual void cloneBasicBlockAnalysis(BasicBlock *F, BasicBlock *T, Loop *L) {}
80 /// deleteAnalysisValue - Delete analysis info associated with value V.
81 virtual void deleteAnalysisValue(Value *V, Loop *L) {}
84 class LPPassManager : public FunctionPass, public PMDataManager {
87 explicit LPPassManager(int Depth);
89 /// run - Execute all of the passes scheduled for execution. Keep track of
90 /// whether any of the passes modifies the module, and if so, return true.
91 bool runOnFunction(Function &F);
93 /// Pass Manager itself does not invalidate any analysis info.
94 // LPPassManager needs LoopInfo.
95 void getAnalysisUsage(AnalysisUsage &Info) const;
97 virtual const char *getPassName() const {
98 return "Loop Pass Manager";
101 virtual PMDataManager *getAsPMDataManager() { return this; }
102 virtual Pass *getAsPass() { return this; }
104 /// Print passes managed by this manager
105 void dumpPassStructure(unsigned Offset);
107 Pass *getContainedPass(unsigned N) {
108 assert(N < PassVector.size() && "Pass number out of range!");
109 Pass *FP = static_cast<Pass *>(PassVector[N]);
113 virtual PassManagerType getPassManagerType() const {
114 return PMT_LoopPassManager;
118 // Delete loop from the loop queue and loop nest (LoopInfo).
119 void deleteLoopFromQueue(Loop *L);
121 // Insert loop into the loop queue and add it as a child of the
123 void insertLoop(Loop *L, Loop *ParentLoop);
125 // Insert a loop into the loop queue.
126 void insertLoopIntoQueue(Loop *L);
128 // Reoptimize this loop. LPPassManager will re-insert this loop into the
129 // queue. This allows LoopPass to change loop nest for the loop. This
130 // utility may send LPPassManager into infinite loops so use caution.
131 void redoLoop(Loop *L);
133 //===--------------------------------------------------------------------===//
134 /// SimpleAnalysis - Provides simple interface to update analysis info
135 /// maintained by various passes. Note, if required this interface can
136 /// be extracted into a separate abstract class but it would require
137 /// additional use of multiple inheritance in Pass class hierarchy, something
138 /// we are trying to avoid.
140 /// cloneBasicBlockSimpleAnalysis - Invoke cloneBasicBlockAnalysis hook for
141 /// all passes that implement simple analysis interface.
142 void cloneBasicBlockSimpleAnalysis(BasicBlock *From, BasicBlock *To, Loop *L);
144 /// deleteSimpleAnalysisValue - Invoke deleteAnalysisValue hook for all passes
145 /// that implement simple analysis interface.
146 void deleteSimpleAnalysisValue(Value *V, Loop *L);
149 std::deque<Loop *> LQ;
156 } // End llvm namespace