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(pid) {}
32 explicit LoopPass(void *pid) : Pass(pid) {}
34 // runOnLoop - This method should be implemented by the subclass to perform
35 // whatever action is necessary for the specified Loop.
36 virtual bool runOnLoop(Loop *L, LPPassManager &LPM) = 0;
37 virtual bool runOnFunctionBody(Function &F, LPPassManager &LPM) {
41 // Initialization and finalization hooks.
42 virtual bool doInitialization(Loop *L, LPPassManager &LPM) {
46 // Finalization hook does not supply Loop because at this time
47 // loop nest is completely different.
48 virtual bool doFinalization() { return false; }
50 // Check if this pass is suitable for the current LPPassManager, if
51 // available. This pass P is not suitable for a LPPassManager if P
52 // is not preserving higher level analysis info used by other
53 // LPPassManager passes. In such case, pop LPPassManager from the
54 // stack. This will force assignPassManager() to create new
55 // LPPassManger as expected.
56 void preparePassManager(PMStack &PMS);
58 /// Assign pass manager to manager this pass
59 virtual void assignPassManager(PMStack &PMS,
60 PassManagerType PMT = PMT_LoopPassManager);
62 /// Return what kind of Pass Manager can manage this pass.
63 virtual PassManagerType getPotentialPassManagerType() const {
64 return PMT_LoopPassManager;
67 //===--------------------------------------------------------------------===//
68 /// SimpleAnalysis - Provides simple interface to update analysis info
69 /// maintained by various passes. Note, if required this interface can
70 /// be extracted into a separate abstract class but it would require
71 /// additional use of multiple inheritance in Pass class hierarchy, something
72 /// we are trying to avoid.
74 /// Each loop pass can override these simple analysis hooks to update
75 /// desired analysis information.
76 /// cloneBasicBlockAnalysis - Clone analysis info associated with basic block.
77 virtual void cloneBasicBlockAnalysis(BasicBlock *F, BasicBlock *T, Loop *L) {}
79 /// deletekAnalysisValue - Delete analysis info associated with value V.
80 virtual void deleteAnalysisValue(Value *V, Loop *L) {}
83 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);
103 Pass *getContainedPass(unsigned N) {
104 assert(N < PassVector.size() && "Pass number out of range!");
105 Pass *FP = static_cast<Pass *>(PassVector[N]);
109 virtual PassManagerType getPassManagerType() const {
110 return PMT_LoopPassManager;
114 // Delete loop from the loop queue and loop nest (LoopInfo).
115 void deleteLoopFromQueue(Loop *L);
117 // Insert loop into the loop nest(LoopInfo) and loop queue(LQ).
118 void insertLoop(Loop *L, Loop *ParentLoop);
120 // Reoptimize this loop. LPPassManager will re-insert this loop into the
121 // queue. This allows LoopPass to change loop nest for the loop. This
122 // utility may send LPPassManager into infinite loops so use caution.
123 void redoLoop(Loop *L);
125 //===--------------------------------------------------------------------===//
126 /// SimpleAnalysis - Provides simple interface to update analysis info
127 /// maintained by various passes. Note, if required this interface can
128 /// be extracted into a separate abstract class but it would require
129 /// additional use of multiple inheritance in Pass class hierarchy, something
130 /// we are trying to avoid.
132 /// cloneBasicBlockSimpleAnalysis - Invoke cloneBasicBlockAnalysis hook for
133 /// all passes that implement simple analysis interface.
134 void cloneBasicBlockSimpleAnalysis(BasicBlock *From, BasicBlock *To, Loop *L);
136 /// deleteSimpleAnalysisValue - Invoke deleteAnalysisValue hook for all passes
137 /// that implement simple analysis interface.
138 void deleteSimpleAnalysisValue(Value *V, Loop *L);
141 std::deque<Loop *> LQ;
148 } // End llvm namespace