1//===-- DiffLog.h - Difference Log Builder and accessories ------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This header defines the interface to the LLVM difference log builder.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_TOOLS_LLVM_DIFF_DIFFLOG_H
14#define LLVM_TOOLS_LLVM_DIFF_DIFFLOG_H
15
16#include "llvm/ADT/SmallVector.h"
17#include "llvm/ADT/StringRef.h"
18
19namespace llvm {
20  class Instruction;
21  class Value;
22  class Consumer;
23
24  /// Trichotomy assumption
25  enum DiffChange { DC_match, DC_left, DC_right };
26
27  /// A temporary-object class for building up log messages.
28  class LogBuilder {
29    Consumer *consumer;
30
31    /// The use of a stored StringRef here is okay because
32    /// LogBuilder should be used only as a temporary, and as a
33    /// temporary it will be destructed before whatever temporary
34    /// might be initializing this format.
35    StringRef Format;
36
37    SmallVector<Value*, 4> Arguments;
38
39  public:
40    LogBuilder(Consumer &c, StringRef Format) : consumer(&c), Format(Format) {}
41    LogBuilder(LogBuilder &&L)
42        : consumer(L.consumer), Format(L.Format),
43          Arguments(std::move(L.Arguments)) {
44      L.consumer = nullptr;
45    }
46
47    LogBuilder &operator<<(Value *V) {
48      Arguments.push_back(V);
49      return *this;
50    }
51
52    ~LogBuilder();
53
54    StringRef getFormat() const;
55    unsigned getNumArguments() const;
56    Value *getArgument(unsigned I) const;
57  };
58
59  /// A temporary-object class for building up diff messages.
60  class DiffLogBuilder {
61    typedef std::pair<Instruction*,Instruction*> DiffRecord;
62    SmallVector<DiffRecord, 20> Diff;
63
64    Consumer &consumer;
65
66  public:
67    DiffLogBuilder(Consumer &c) : consumer(c) {}
68    ~DiffLogBuilder();
69
70    void addMatch(Instruction *L, Instruction *R);
71    // HACK: VS 2010 has a bug in the stdlib that requires this.
72    void addLeft(Instruction *L);
73    void addRight(Instruction *R);
74
75    unsigned getNumLines() const;
76    DiffChange getLineKind(unsigned I) const;
77    Instruction *getLeft(unsigned I) const;
78    Instruction *getRight(unsigned I) const;
79  };
80
81}
82
83#endif
84