1 //===- lib/Linker/LinkItems.cpp - Link LLVM objects and libraries ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Reid Spencer and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains routines to handle linking together LLVM bytecode files,
11 // and to handle annoying things like static libraries.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Linker.h"
16 #include "llvm/Module.h"
20 // LinkItems - This function is the main entry point into linking. It takes a
21 // list of LinkItem which indicates the order the files should be linked and
22 // how each file should be treated (plain file or with library search). The
23 // function only links bytecode and produces a result list of items that are
26 Linker::LinkInItems(const ItemList& Items, ItemList& NativeItems) {
27 // Clear the NativeItems just in case
30 // For each linkage item ...
31 for (ItemList::const_iterator I = Items.begin(), E = Items.end();
34 // Link in the library suggested.
35 bool is_native = false;
36 if (LinkInLibrary(I->first, is_native))
39 NativeItems.push_back(*I);
41 // Link in the file suggested
42 bool is_native = false;
43 if (LinkInFile(sys::Path(I->first), is_native))
46 NativeItems.push_back(*I);
50 // At this point we have processed all the link items provided to us. Since
51 // we have an aggregated module at this point, the dependent libraries in
52 // that module should also be aggregated with duplicates eliminated. This is
53 // now the time to process the dependent libraries to resolve any remaining
56 for (Module::lib_iterator I = Composite->lib_begin(),
57 E = Composite->lib_end(); I != E; ++I)
58 if(LinkInLibrary(*I, is_native))
65 /// LinkInLibrary - links one library into the HeadModule.
67 bool Linker::LinkInLibrary(const std::string& Lib, bool& is_native) {
69 // Determine where this library lives.
70 sys::Path Pathname = FindLib(Lib);
71 if (Pathname.isEmpty())
72 return warning("Cannot find library '" + Lib + "'");
74 // If its an archive, try to link it in
76 Pathname.getMagicNumber(Magic, 64);
77 switch (sys::IdentifyFileType(Magic.c_str(), 64)) {
78 default: assert(0 && "Bad file type identification");
79 case sys::Unknown_FileType:
80 return warning("Supposed library '" + Lib + "' isn't a library.");
82 case sys::Bytecode_FileType:
83 case sys::CompressedBytecode_FileType:
85 if (LinkInFile(Pathname, is_native))
86 return error("Cannot link file '" + Pathname.toString() + "'");
89 case sys::Archive_FileType:
90 if (LinkInArchive(Pathname))
91 return error("Cannot link archive '" + Pathname.toString() + "'");
94 case sys::ELF_FileType:
95 case sys::Mach_O_FileType:
96 case sys::COFF_FileType:
103 /// LinkLibraries - takes the specified library files and links them into the
104 /// main bytecode object file.
107 /// Libraries - The list of libraries to link into the module.
110 /// FALSE - No error.
113 bool Linker::LinkInLibraries(const std::vector<std::string> &Libraries) {
115 // Process the set of libraries we've been provided.
116 bool is_native = false;
117 for (unsigned i = 0; i < Libraries.size(); ++i)
118 if (LinkInLibrary(Libraries[i], is_native))
121 // At this point we have processed all the libraries provided to us. Since
122 // we have an aggregated module at this point, the dependent libraries in
123 // that module should also be aggregated with duplicates eliminated. This is
124 // now the time to process the dependent libraries to resolve any remaining
126 const Module::LibraryListType& DepLibs = Composite->getLibraries();
127 for (Module::LibraryListType::const_iterator I = DepLibs.begin(),
128 E = DepLibs.end(); I != E; ++I)
129 if (LinkInLibrary(*I, is_native))
135 /// LinkInFile - opens a bytecode file and links in all objects which
136 /// provide symbols that are currently undefined.
139 /// File - The pathname of the bytecode file.
142 /// ErrorMessage - A C++ string detailing what error occurred, if any.
145 /// TRUE - An error occurred.
146 /// FALSE - No errors.
148 bool Linker::LinkInFile(const sys::Path &File, bool &is_native) {
150 // Make sure we can at least read the file
152 return error("Cannot find linker input '" + File.toString() + "'");
154 // If its an archive, try to link it in
156 File.getMagicNumber(Magic, 64);
157 switch (sys::IdentifyFileType(Magic.c_str(), 64)) {
158 default: assert(0 && "Bad file type identification");
159 case sys::Unknown_FileType:
160 return warning("Supposed object file '" + File.toString() +
161 "' not recognized as such");
163 case sys::Archive_FileType:
164 // A user may specify an ar archive without -l, perhaps because it
165 // is not installed as a library. Detect that and link the archive.
166 verbose("Linking archive file '" + File.toString() + "'");
167 if (LinkInArchive(File))
168 return error("Cannot link archive '" + File.toString() + "'");
171 case sys::Bytecode_FileType:
172 case sys::CompressedBytecode_FileType: {
173 verbose("Linking bytecode file '" + File.toString() + "'");
174 std::auto_ptr<Module> M(LoadObject(File));
176 return error("Cannot load file '" + File.toString() + "'" + Error);
177 if (LinkInModule(M.get()))
178 return error("Cannot link file '" + File.toString() + "'" + Error);
180 verbose("Linked in file '" + File.toString() + "'");
184 case sys::ELF_FileType:
185 case sys::Mach_O_FileType:
186 case sys::COFF_FileType:
193 /// LinkFiles - takes a module and a list of files and links them all together.
194 /// It locates the file either in the current directory, as its absolute
195 /// or relative pathname, or as a file somewhere in LLVM_LIB_SEARCH_PATH.
198 /// Files - A vector of sys::Path indicating the LLVM bytecode filenames
199 /// to be linked. The names can refer to a mixture of pure LLVM
200 /// bytecode files and archive (ar) formatted files.
203 /// FALSE - No errors.
204 /// TRUE - Some error occurred.
206 bool Linker::LinkInFiles(const std::vector<sys::Path> &Files) {
208 for (unsigned i = 0; i < Files.size(); ++i)
209 if (LinkInFile(Files[i], is_native))