1//===-- llvm/Transforms/Utils/SimplifyIndVar.h - Indvar Utils ---*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines in interface for induction variable simplification. It does 11// not define any actual pass or policy, but provides a single function to 12// simplify a loop's induction variables based on ScalarEvolution. 13// 14//===----------------------------------------------------------------------===// 15 16#ifndef LLVM_TRANSFORMS_UTILS_SIMPLIFYINDVAR_H 17#define LLVM_TRANSFORMS_UTILS_SIMPLIFYINDVAR_H 18 19#include "llvm/IR/ValueHandle.h" 20 21namespace llvm { 22 23class CastInst; 24class DominatorTree; 25class Loop; 26class LoopInfo; 27class PHINode; 28class ScalarEvolution; 29 30/// Interface for visiting interesting IV users that are recognized but not 31/// simplified by this utility. 32class IVVisitor { 33protected: 34 const DominatorTree *DT = nullptr; 35 36 virtual void anchor(); 37 38public: 39 IVVisitor() = default; 40 virtual ~IVVisitor() = default; 41 42 const DominatorTree *getDomTree() const { return DT; } 43 virtual void visitCast(CastInst *Cast) = 0; 44}; 45 46/// simplifyUsersOfIV - Simplify instructions that use this induction variable 47/// by using ScalarEvolution to analyze the IV's recurrence. 48bool simplifyUsersOfIV(PHINode *CurrIV, ScalarEvolution *SE, DominatorTree *DT, 49 LoopInfo *LI, SmallVectorImpl<WeakTrackingVH> &Dead, 50 IVVisitor *V = nullptr); 51 52/// SimplifyLoopIVs - Simplify users of induction variables within this 53/// loop. This does not actually change or add IVs. 54bool simplifyLoopIVs(Loop *L, ScalarEvolution *SE, DominatorTree *DT, 55 LoopInfo *LI, SmallVectorImpl<WeakTrackingVH> &Dead); 56 57} // end namespace llvm 58 59#endif // LLVM_TRANSFORMS_UTILS_SIMPLIFYINDVAR_H 60