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/IR/FunctionInfo.h" 14 #include "llvm/Linker/IRMover.h" 15 16 namespace llvm { 17 class Module; 18 class StructType; 19 class Type; 20 21 /// This class provides the core functionality of linking in LLVM. It keeps a 22 /// pointer to the merged module so far. It doesn't take ownership of the 23 /// module since it is assumed that the user of this class will want to do 24 /// something with it after the linking. 25 class Linker { 26 IRMover Mover; 27 28 public: 29 enum Flags { 30 None = 0, 31 OverrideFromSrc = (1 << 0), 32 LinkOnlyNeeded = (1 << 1), 33 InternalizeLinkedSymbols = (1 << 2) 34 }; 35 36 Linker(Module &M); 37 38 /// \brief Link \p Src into the composite. 39 /// 40 /// Passing OverrideSymbols as true will have symbols from Src 41 /// shadow those in the Dest. 42 /// For ThinLTO function importing/exporting the \p FunctionInfoIndex 43 /// is passed. If \p FunctionsToImport is provided, only the functions that 44 /// are part of the set will be imported from the source module. 45 /// The \p ValIDToTempMDMap is populated by the linker when function 46 /// importing is performed. 47 /// 48 /// Returns true on error. 49 bool linkInModule(std::unique_ptr<Module> Src, unsigned Flags = Flags::None, 50 const FunctionInfoIndex *Index = nullptr, 51 DenseSet<const GlobalValue *> *FunctionsToImport = nullptr, 52 DenseMap<unsigned, MDNode *> *ValIDToTempMDMap = nullptr); 53 54 /// This exists to implement the deprecated LLVMLinkModules C api. Don't use 55 /// for anything else. 56 bool linkInModuleForCAPI(Module &Src); 57 58 static bool linkModules(Module &Dest, std::unique_ptr<Module> Src, 59 unsigned Flags = Flags::None); 60 61 /// \brief Link metadata from \p Src into the composite. The source is 62 /// destroyed. 63 /// 64 /// The \p ValIDToTempMDMap sound have been populated earlier during function 65 /// importing from \p Src. 66 bool linkInMetadata(Module &Src, 67 DenseMap<unsigned, MDNode *> *ValIDToTempMDMap); 68 }; 69 70 /// Create a new module with exported local functions renamed and promoted 71 /// for ThinLTO. 72 std::unique_ptr<Module> renameModuleForThinLTO(std::unique_ptr<Module> M, 73 const FunctionInfoIndex *Index); 74 75 } // End llvm namespace 76 77 #endif 78
