aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/llvm14/include/llvm/Transforms/Utils/SimplifyIndVar.h
blob: 375bf2963a67a1dab28bdd76bd1e956a633cde89 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
#pragma once

#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-parameter"
#endif

//===-- llvm/Transforms/Utils/SimplifyIndVar.h - Indvar Utils ---*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines in interface for induction variable simplification. It does
// not define any actual pass or policy, but provides a single function to
// simplify a loop's induction variables based on ScalarEvolution.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_TRANSFORMS_UTILS_SIMPLIFYINDVAR_H
#define LLVM_TRANSFORMS_UTILS_SIMPLIFYINDVAR_H

#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/ValueHandle.h"

namespace llvm {

class CastInst;
class DominatorTree;
class Loop;
class LoopInfo;
class PHINode;
class ScalarEvolution;
class SCEVExpander;
class TargetTransformInfo;

/// Interface for visiting interesting IV users that are recognized but not
/// simplified by this utility.
class IVVisitor {
protected:
  const DominatorTree *DT = nullptr;

  virtual void anchor();

public:
  IVVisitor() = default;
  virtual ~IVVisitor() = default;

  const DominatorTree *getDomTree() const { return DT; }
  virtual void visitCast(CastInst *Cast) = 0;
};

/// simplifyUsersOfIV - Simplify instructions that use this induction variable
/// by using ScalarEvolution to analyze the IV's recurrence.
bool simplifyUsersOfIV(PHINode *CurrIV, ScalarEvolution *SE, DominatorTree *DT,
                       LoopInfo *LI, const TargetTransformInfo *TTI,
                       SmallVectorImpl<WeakTrackingVH> &Dead,
                       SCEVExpander &Rewriter, IVVisitor *V = nullptr);

/// SimplifyLoopIVs - Simplify users of induction variables within this
/// loop. This does not actually change or add IVs.
bool simplifyLoopIVs(Loop *L, ScalarEvolution *SE, DominatorTree *DT,
                     LoopInfo *LI, const TargetTransformInfo *TTI,
                     SmallVectorImpl<WeakTrackingVH> &Dead);

/// Collect information about induction variables that are used by sign/zero
/// extend operations. This information is recorded by CollectExtend and provides
/// the input to WidenIV.
struct WideIVInfo {
  PHINode *NarrowIV = nullptr;

  // Widest integer type created [sz]ext
  Type *WidestNativeType = nullptr;

  // Was a sext user seen before a zext?
  bool IsSigned = false;
};

/// Widen Induction Variables - Extend the width of an IV to cover its
/// widest uses.
PHINode *createWideIV(const WideIVInfo &WI,
    LoopInfo *LI, ScalarEvolution *SE, SCEVExpander &Rewriter,
    DominatorTree *DT, SmallVectorImpl<WeakTrackingVH> &DeadInsts,
    unsigned &NumElimExt, unsigned &NumWidened,
    bool HasGuards, bool UsePostIncrementRanges);

} // end namespace llvm

#endif // LLVM_TRANSFORMS_UTILS_SIMPLIFYINDVAR_H

#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif