1 //===- llvm-link.cpp - Low-level LLVM linker ------------------------------===//
8 //===----------------------------------------------------------------------===//
11 //  llvm-link a.bc b.bc c.bc -o x.bc
13 //===----------------------------------------------------------------------===//
21 #include "llvm/IR/Module.h"
52 // llvm-link to simulate ThinLTO backend processes.
53 static cl::list<std::string> Imports(  variable
58 // Option to support testing of function importing. The module summary
59 // must be specified in the case were we request imports via the -import
60 // option, as well as when compiling any module with functions that may be
61 // exported (imported by a different llvm-link -import invocation), to ensure
64     SummaryIndex("summary-index", cl::desc("Module summary index filename"),
68 OutputFilename("o", cl::desc("Override output filename"), cl::init("-"),
75     DisableDITypeMap("disable-debug-info-type-map",
79 OnlyNeeded("only-needed", cl::desc("Link only needed symbols"));
95 SuppressWarnings("suppress-warnings", cl::desc("Suppress all linking warnings"),
99     "preserve-bc-uselistorder",
100     cl::desc("Preserve use-list order when writing LLVM bitcode."),
104     "preserve-ll-uselistorder",
105     cl::desc("Preserve use-list order when writing LLVM assembly."),
111 static std::unique_ptr<Module> loadFile(const char *argv0,  in loadFile()
117   std::unique_ptr<Module> Result =  in loadFile()
125     Result->materializeMetadata();  in loadFile()
134 /// Helper to load on demand a Module from file and cache it for subsequent
137   /// Cache of lazily loaded module for import.
138   StringMap<std::unique_ptr<Module>> ModuleMap;
140   /// Retrieve a Module from the cache or lazily load it on demand.
141   std::function<std::unique_ptr<Module>(const char *argv0,
146   /// Create the loader, Module will be initialized in \p Context.
147   ModuleLazyLoaderCache(std::function<std::unique_ptr<Module>(  in ModuleLazyLoaderCache()
152   /// Retrieve a Module from the cache or lazily load it on demand.
153   Module &operator()(const char *argv0, const std::string &FileName);
155   std::unique_ptr<Module> takeModule(const std::string &FileName) {  in takeModule()
158     std::unique_ptr<Module> Ret = std::move(I->second);  in takeModule()
164 // Get a Module for \p FileName from the cache, or load it lazily.
165 Module &ModuleLazyLoaderCache::operator()(const char *argv0,  in operator ()()
167   auto &Module = ModuleMap[Identifier];  in operator ()()  local
168   if (!Module)  in operator ()()
169     Module = createLazyModule(argv0, Identifier);  in operator ()()
170   return *Module;  in operator ()()
199 /// Import any functions requested via the -import option.
213   // Map of Module -> List of globals to import from the Module  in importFunctions()
220   for (const auto &Import : Imports) {  in importFunctions()
230     // Load the specified source module.  in importFunctions()
235              << ": error: input module is broken!\n";  in importFunctions()
241       errs() << "Ignoring import request for non-existent function "  in importFunctions()
248     if (F->hasWeakAnyLinkage()) {  in importFunctions()
249       errs() << "Ignoring import request for weak-any function " << FunctionName  in importFunctions()
260     F->materialize();  in importFunctions()
263   // Do the actual import of globals now, one Module at a time  in importFunctions()
265     // Get the module for the import  in importFunctions()
267     std::unique_ptr<Module> SrcModule =  in importFunctions()
269     assert(&Context == &SrcModule->getContext() && "Context mismatch");  in importFunctions()
273     SrcModule->materializeMetadata();  in importFunctions()
296     std::unique_ptr<Module> M = loadFile(argv0, File, Context);  in linkFiles()
303     // doing that debug metadata in the src module might already be pointing to  in linkFiles()
306       errs() << argv0 << ": " << File << ": error: input module is broken!\n";  in linkFiles()
310     // If a module summary index is supplied, load it so linkInModule can treat  in linkFiles()
353   auto Composite = make_unique<Module>("llvm-link", Context);  in main()
366   // Next the -override ones.  in main()
371   // Import any functions requested via -import  in main()
385     errs() << argv[0] << ": error: linked module is broken!\n";  in main()
391     Composite->print(Out.os(), nullptr, PreserveAssemblyUseListOrder);  in main()