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/Support/CommandLine.h"
20#include "llvm/Support/ValueHandle.h"
21
22namespace llvm {
23
24class CastInst;
25class IVUsers;
26class Loop;
27class LPPassManager;
28class PHINode;
29class ScalarEvolution;
30
31/// Interface for visiting interesting IV users that are recognized but not
32/// simplified by this utility.
33class IVVisitor {
34  virtual void anchor();
35public:
36  virtual ~IVVisitor() {}
37  virtual void visitCast(CastInst *Cast) = 0;
38};
39
40/// simplifyUsersOfIV - Simplify instructions that use this induction variable
41/// by using ScalarEvolution to analyze the IV's recurrence.
42bool simplifyUsersOfIV(PHINode *CurrIV, ScalarEvolution *SE, LPPassManager *LPM,
43                       SmallVectorImpl<WeakVH> &Dead, IVVisitor *V = NULL);
44
45/// SimplifyLoopIVs - Simplify users of induction variables within this
46/// loop. This does not actually change or add IVs.
47bool simplifyLoopIVs(Loop *L, ScalarEvolution *SE, LPPassManager *LPM,
48                     SmallVectorImpl<WeakVH> &Dead);
49
50} // namespace llvm
51
52#endif
53