1//===- Linker.h - Module Linker Interface -----------------------*- 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#ifndef LLVM_LINKER_LINKER_H
11#define LLVM_LINKER_LINKER_H
12
13#include "llvm/Linker/IRMover.h"
14
15namespace llvm {
16class Module;
17class StructType;
18class Type;
19
20/// This class provides the core functionality of linking in LLVM. It keeps a
21/// pointer to the merged module so far. It doesn't take ownership of the
22/// module since it is assumed that the user of this class will want to do
23/// something with it after the linking.
24class Linker {
25  IRMover Mover;
26
27public:
28  enum Flags {
29    None = 0,
30    OverrideFromSrc = (1 << 0),
31    LinkOnlyNeeded = (1 << 1),
32    InternalizeLinkedSymbols = (1 << 2),
33    /// Don't force link referenced linkonce definitions, import declaration.
34    DontForceLinkLinkonceODR = (1 << 3)
35
36  };
37
38  Linker(Module &M);
39
40  /// \brief Link \p Src into the composite.
41  ///
42  /// Passing OverrideSymbols as true will have symbols from Src
43  /// shadow those in the Dest.
44  /// For ThinLTO function importing/exporting the \p ModuleSummaryIndex
45  /// is passed. If \p GlobalsToImport is provided, only the globals that
46  /// are part of the set will be imported from the source module.
47  ///
48  /// Returns true on error.
49  bool linkInModule(std::unique_ptr<Module> Src, unsigned Flags = Flags::None,
50                    DenseSet<const GlobalValue *> *GlobalsToImport = nullptr);
51
52  static bool linkModules(Module &Dest, std::unique_ptr<Module> Src,
53                          unsigned Flags = Flags::None);
54};
55
56} // End llvm namespace
57
58#endif
59