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
19#include "llvm/ADT/StringRef.h"
20#include "llvm/Support/Compiler.h"
21
22namespace llvm {
23
24class raw_ostream;
25template <typename ValueTy> class StringMapEntry;
26
27// This is a Name X SelectionKind pair. The reason for having this be an
28// independent object instead of just adding the name and the SelectionKind
29// to a GlobalObject is that it is invalid to have two Comdats with the same
30// name but different SelectionKind. This structure makes that unrepresentable.
31class Comdat {
32public:
33  enum SelectionKind {
34    Any,          ///< The linker may choose any COMDAT.
35    ExactMatch,   ///< The data referenced by the COMDAT must be the same.
36    Largest,      ///< The linker will choose the largest COMDAT.
37    NoDuplicates, ///< No other Module may specify this COMDAT.
38    SameSize,     ///< The data referenced by the COMDAT must be the same size.
39  };
40
41  Comdat(Comdat &&C);
42  SelectionKind getSelectionKind() const { return SK; }
43  void setSelectionKind(SelectionKind Val) { SK = Val; }
44  StringRef getName() const;
45  void print(raw_ostream &OS) const;
46  void dump() const;
47
48private:
49  friend class Module;
50  Comdat();
51  Comdat(SelectionKind SK, StringMapEntry<Comdat> *Name);
52  Comdat(const Comdat &) = delete;
53
54  // Points to the map in Module.
55  StringMapEntry<Comdat> *Name;
56  SelectionKind SK;
57};
58
59inline raw_ostream &operator<<(raw_ostream &OS, const Comdat &C) {
60  C.print(OS);
61  return OS;
62}
63
64} // end llvm namespace
65
66#endif
67