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"
28 class LoopPass : public Pass {
31 explicit LoopPass(intptr_t pid) : Pass(pid) {}
33 // runOnLoop - This method should be implemented by the subclass to perform
34 // whatever action is necessary for the specfied Loop.
35 virtual bool runOnLoop (Loop *L, LPPassManager &LPM) = 0;
36 virtual bool runOnFunctionBody (Function &F, LPPassManager &LPM) {
40 // Initialization and finalization hooks.
41 virtual bool doInitialization(Loop *L, LPPassManager &LPM) {
45 // Finalization hook does not supply Loop because at this time
46 // loop nest is completely different.
47 virtual bool doFinalization() { return false; }
49 // Check if this pass is suitable for the current LPPassManager, if
50 // available. This pass P is not suitable for a LPPassManager if P
51 // is not preserving higher level analysis info used by other
52 // LPPassManager passes. In such case, pop LPPassManager from the
53 // stack. This will force assignPassManager() to create new
54 // LPPassManger as expected.
55 void preparePassManager(PMStack &PMS);
57 /// Assign pass manager to manager this pass
58 virtual void assignPassManager(PMStack &PMS,
59 PassManagerType PMT = PMT_LoopPassManager);
61 /// Return what kind of Pass Manager can manage this pass.
62 virtual PassManagerType getPotentialPassManagerType() const {
63 return PMT_LoopPassManager;
66 //===--------------------------------------------------------------------===//
67 /// SimpleAnalysis - Provides simple interface to update analysis info
68 /// maintained by various passes. Note, if required this interface can
69 /// be extracted into a separate abstract class but it would require
70 /// additional use of multiple inheritance in Pass class hierarcy, someting
71 /// we are trying to avoid.
73 /// Each loop pass can override these simple analysis hookss to update
74 /// desired analysis information.
75 /// cloneBasicBlockAnalysis - Clone analysis info associated with basic block.
76 virtual void cloneBasicBlockAnalysis(BasicBlock *F, BasicBlock *T, Loop *L) {}
78 /// deletekAnalysisValue - Delete analysis info associated with value V.
79 virtual void deleteAnalysisValue(Value *V, Loop *L) {}
82 class LPPassManager : public FunctionPass, public PMDataManager {
86 explicit LPPassManager(int Depth);
88 /// run - Execute all of the passes scheduled for execution. Keep track of
89 /// whether any of the passes modifies the module, and if so, return true.
90 bool runOnFunction(Function &F);
92 /// Pass Manager itself does not invalidate any analysis info.
93 // LPPassManager needs LoopInfo.
94 void getAnalysisUsage(AnalysisUsage &Info) const;
96 virtual const char *getPassName() const {
97 return "Loop Pass Manager";
100 // Print passes managed by this manager
101 void dumpPassStructure(unsigned Offset) {
102 llvm::cerr << std::string(Offset*2, ' ') << "Loop Pass Manager\n";
103 for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
104 Pass *P = getContainedPass(Index);
105 P->dumpPassStructure(Offset + 1);
106 dumpLastUses(P, Offset+1);
110 Pass *getContainedPass(unsigned N) {
111 assert ( N < PassVector.size() && "Pass number out of range!");
112 Pass *FP = static_cast<Pass *>(PassVector[N]);
116 virtual PassManagerType getPassManagerType() const {
117 return PMT_LoopPassManager;
121 // Delete loop from the loop queue and loop nest (LoopInfo).
122 void deleteLoopFromQueue(Loop *L);
124 // Inset loop into the loop nest(LoopInfo) and loop queue(LQ).
125 void insertLoop(Loop *L, Loop *ParentLoop);
127 // Reoptimize this loop. LPPassManager will re-insert this loop into the
128 // queue. This allows LoopPass to change loop nest for the loop. This
129 // utility may send LPPassManager into infinite loops so use caution.
130 void redoLoop(Loop *L);
132 //===--------------------------------------------------------------------===//
133 /// SimpleAnalysis - Provides simple interface to update analysis info
134 /// maintained by various passes. Note, if required this interface can
135 /// be extracted into a separate abstract class but it would require
136 /// additional use of multiple inheritance in Pass class hierarcy, someting
137 /// we are trying to avoid.
139 /// cloneBasicBlockSimpleAnalysis - Invoke cloneBasicBlockAnalysis hook for
140 /// all passes that implement simple analysis interface.
141 void cloneBasicBlockSimpleAnalysis(BasicBlock *From, BasicBlock *To, Loop *L);
143 /// deleteSimpleAnalysisValue - Invoke deleteAnalysisValue hook for all passes
144 /// that implement simple analysis interface.
145 void deleteSimpleAnalysisValue(Value *V, Loop *L);
147 std::deque<Loop *> LQ;
154 } // End llvm namespace