1//===- llvm/IR/Comdat.h - Comdat definitions --------------------*- 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/// @file
11/// This file contains the declaration of the Comdat class, which represents a
12/// single COMDAT in LLVM.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_IR_COMDAT_H
17#define LLVM_IR_COMDAT_H
18
19namespace llvm {
20
21class raw_ostream;
22class StringRef;
23template <typename ValueTy> class StringMapEntry;
24
25// This is a Name X SelectionKind pair. The reason for having this be an
26// independent object instead of just adding the name and the SelectionKind
27// to a GlobalObject is that it is invalid to have two Comdats with the same
28// name but different SelectionKind. This structure makes that unrepresentable.
29class Comdat {
30public:
31  enum SelectionKind {
32    Any,          ///< The linker may choose any COMDAT.
33    ExactMatch,   ///< The data referenced by the COMDAT must be the same.
34    Largest,      ///< The linker will choose the largest COMDAT.
35    NoDuplicates, ///< No other Module may specify this COMDAT.
36    SameSize,     ///< The data referenced by the COMDAT must be the same size.
37  };
38
39  Comdat(const Comdat &) = delete;
40  Comdat(Comdat &&C);
41
42  SelectionKind getSelectionKind() const { return SK; }
43  void setSelectionKind(SelectionKind Val) { SK = Val; }
44  StringRef getName() const;
45  void print(raw_ostream &OS, bool IsForDebug = false) const;
46  void dump() const;
47
48private:
49  friend class Module;
50
51  Comdat();
52
53  // Points to the map in Module.
54  StringMapEntry<Comdat> *Name = nullptr;
55  SelectionKind SK = Any;
56};
57
58inline raw_ostream &operator<<(raw_ostream &OS, const Comdat &C) {
59  C.print(OS);
60  return OS;
61}
62
63} // end namespace llvm
64
65#endif // LLVM_IR_COMDAT_H
66