llvm-6502/include/llvm/Analysis/LoopPass.h

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5.8 KiB
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//===- LoopPass.h - LoopPass class ----------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines LoopPass class. All loop optimization
// and transformation passes are derived from LoopPass.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_LOOPPASS_H
#define LLVM_ANALYSIS_LOOPPASS_H
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/LegacyPassManagers.h"
#include "llvm/Pass.h"
#include <deque>
namespace llvm {
class LPPassManager;
class Function;
class PMStack;
class LoopPass : public Pass {
public:
explicit LoopPass(char &pid) : Pass(PT_Loop, pid) {}
/// getPrinterPass - Get a pass to print the function corresponding
/// to a Loop.
Pass *createPrinterPass(raw_ostream &O,
const std::string &Banner) const override;
// runOnLoop - This method should be implemented by the subclass to perform
// whatever action is necessary for the specified Loop.
virtual bool runOnLoop(Loop *L, LPPassManager &LPM) = 0;
using llvm::Pass::doInitialization;
using llvm::Pass::doFinalization;
// Initialization and finalization hooks.
virtual bool doInitialization(Loop *L, LPPassManager &LPM) {
return false;
}
// Finalization hook does not supply Loop because at this time
// loop nest is completely different.
virtual bool doFinalization() { return false; }
// Check if this pass is suitable for the current LPPassManager, if
// available. This pass P is not suitable for a LPPassManager if P
// is not preserving higher level analysis info used by other
// LPPassManager passes. In such case, pop LPPassManager from the
// stack. This will force assignPassManager() to create new
// LPPassManger as expected.
void preparePassManager(PMStack &PMS) override;
/// Assign pass manager to manage this pass
void assignPassManager(PMStack &PMS, PassManagerType PMT) override;
/// Return what kind of Pass Manager can manage this pass.
PassManagerType getPotentialPassManagerType() const override {
return PMT_LoopPassManager;
}
//===--------------------------------------------------------------------===//
/// SimpleAnalysis - Provides simple interface to update analysis info
/// maintained by various passes. Note, if required this interface can
/// be extracted into a separate abstract class but it would require
/// additional use of multiple inheritance in Pass class hierarchy, something
/// we are trying to avoid.
/// Each loop pass can override these simple analysis hooks to update
/// desired analysis information.
/// cloneBasicBlockAnalysis - Clone analysis info associated with basic block.
virtual void cloneBasicBlockAnalysis(BasicBlock *F, BasicBlock *T, Loop *L) {}
/// deleteAnalysisValue - Delete analysis info associated with value V.
virtual void deleteAnalysisValue(Value *V, Loop *L) {}
protected:
/// skipOptnoneFunction - Containing function has Attribute::OptimizeNone
/// and most transformation passes should skip it.
bool skipOptnoneFunction(const Loop *L) const;
};
class LPPassManager : public FunctionPass, public PMDataManager {
public:
static char ID;
explicit LPPassManager();
/// run - Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the module, and if so, return true.
bool runOnFunction(Function &F) override;
/// Pass Manager itself does not invalidate any analysis info.
// LPPassManager needs LoopInfo.
void getAnalysisUsage(AnalysisUsage &Info) const override;
const char *getPassName() const override {
return "Loop Pass Manager";
}
PMDataManager *getAsPMDataManager() override { return this; }
Pass *getAsPass() override { return this; }
/// Print passes managed by this manager
void dumpPassStructure(unsigned Offset) override;
LoopPass *getContainedPass(unsigned N) {
assert(N < PassVector.size() && "Pass number out of range!");
LoopPass *LP = static_cast<LoopPass *>(PassVector[N]);
return LP;
}
PassManagerType getPassManagerType() const override {
return PMT_LoopPassManager;
}
public:
// Delete loop from the loop queue and loop nest (LoopInfo).
void deleteLoopFromQueue(Loop *L);
// Insert loop into the loop queue and add it as a child of the
// given parent.
void insertLoop(Loop *L, Loop *ParentLoop);
// Insert a loop into the loop queue.
void insertLoopIntoQueue(Loop *L);
// Reoptimize this loop. LPPassManager will re-insert this loop into the
// queue. This allows LoopPass to change loop nest for the loop. This
// utility may send LPPassManager into infinite loops so use caution.
void redoLoop(Loop *L);
//===--------------------------------------------------------------------===//
/// SimpleAnalysis - Provides simple interface to update analysis info
/// maintained by various passes. Note, if required this interface can
/// be extracted into a separate abstract class but it would require
/// additional use of multiple inheritance in Pass class hierarchy, something
/// we are trying to avoid.
/// cloneBasicBlockSimpleAnalysis - Invoke cloneBasicBlockAnalysis hook for
/// all passes that implement simple analysis interface.
void cloneBasicBlockSimpleAnalysis(BasicBlock *From, BasicBlock *To, Loop *L);
/// deleteSimpleAnalysisValue - Invoke deleteAnalysisValue hook for all passes
/// that implement simple analysis interface.
void deleteSimpleAnalysisValue(Value *V, Loop *L);
private:
std::deque<Loop *> LQ;
bool skipThisLoop;
bool redoThisLoop;
LoopInfo *LI;
Loop *CurrentLoop;
};
} // End llvm namespace
#endif