1 //===- LoopPass.h - LoopPass class ----------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Devang Patel and is distributed under
6 // the University of Illinois Open Source 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 {
32 // runOnLoop - THis method should be implemented by the subclass to perform
33 // whatever action is necessary for the specfied Loop.
34 virtual bool runOnLoop (Loop *L, LPPassManager &LPM) = 0;
35 virtual bool runOnFunctionBody (Function &F, LPPassManager &LPM) {
39 // Initialization and finalization hooks.
40 virtual bool doInitialization(Loop *L, LPPassManager &LPM) {
44 // Finalization hook does not supply Loop because at this time
45 // loop nest is completely different.
46 virtual bool doFinalization() { return false; }
48 // Check if this pass is suitable for the current LPPassManager, if
49 // available. This pass P is not suitable for a LPPassManager if P
50 // is not preserving higher level analysis info used by other
51 // LPPassManager passes. In such case, pop LPPassManager from the
52 // stack. This will force assignPassManager() to create new
53 // LPPassManger as expected.
54 void preparePassManager(PMStack &PMS);
56 /// Assign pass manager to manager this pass
57 virtual void assignPassManager(PMStack &PMS,
58 PassManagerType PMT = PMT_LoopPassManager);
62 class LPPassManager : public FunctionPass, public PMDataManager {
65 LPPassManager(int Depth);
67 /// run - Execute all of the passes scheduled for execution. Keep track of
68 /// whether any of the passes modifies the module, and if so, return true.
69 bool runOnFunction(Function &F);
71 /// Pass Manager itself does not invalidate any analysis info.
72 void getAnalysisUsage(AnalysisUsage &Info) const {
73 // LPPassManager needs LoopInfo. In the long term LoopInfo class will
74 // be consumed by LPPassManager.
75 Info.addRequired<LoopInfo>();
76 Info.setPreservesAll();
79 virtual const char *getPassName() const {
80 return "Loop Pass Manager";
83 // Print passes managed by this manager
84 void dumpPassStructure(unsigned Offset) {
85 llvm::cerr << std::string(Offset*2, ' ') << "Loop Pass Manager\n";
86 for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
87 Pass *P = getContainedPass(Index);
88 P->dumpPassStructure(Offset + 1);
89 dumpLastUses(P, Offset+1);
93 Pass *getContainedPass(unsigned N) {
94 assert ( N < PassVector.size() && "Pass number out of range!");
95 Pass *FP = static_cast<Pass *>(PassVector[N]);
99 virtual PassManagerType getPassManagerType() const {
100 return PMT_LoopPassManager;
104 // Delete loop from the loop queue. This is used by Loop pass to inform
105 // Loop Pass Manager that it should skip rest of the passes for this loop.
106 void deleteLoopFromQueue(Loop *L);
108 // Reoptimize this loop. LPPassManager will re-insert this loop into the
109 // queue. This allows LoopPass to change loop nest for the loop. This
110 // utility may send LPPassManager into infinite loops so use caution.
111 void redoLoop(Loop *L);
113 std::deque<Loop *> LQ;
120 } // End llvm namespace