-//===- Linker.cpp - Link together LLVM objects and libraries --------------===//
+//===- lib/Linker/LinkArchives.cpp - Link LLVM objects and libraries ------===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
-#include "gccld.h"
+#include "llvm/Linker.h"
#include "llvm/Module.h"
+#include "llvm/ModuleProvider.h"
#include "llvm/PassManager.h"
+#include "llvm/ADT/SetOperations.h"
#include "llvm/Bytecode/Reader.h"
+#include "llvm/Bytecode/Archive.h"
#include "llvm/Bytecode/WriteBytecodePass.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/Linker.h"
-#include "Support/CommandLine.h"
-#include "Support/FileUtilities.h"
-#include "Support/Signals.h"
-#include "Support/SystemUtils.h"
+#include "llvm/Config/config.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/Timer.h"
+#include "llvm/System/Signals.h"
+#include "llvm/Support/SystemUtils.h"
#include <algorithm>
#include <fstream>
#include <memory>
#include <set>
-
-/// FileExists - determines if the specified filename exists and is readable.
-///
-/// Inputs:
-/// FN - The name of the file.
-///
-/// Outputs:
-/// None.
-///
-/// Return Value:
-/// TRUE - The file exists and is readable.
-/// FALSE - The file does not exist or is unreadable.
-///
-static inline bool FileExists(const std::string &FN) {
- return access(FN.c_str(), R_OK | F_OK) != -1;
-}
-
-/// IsArchive - determines if the specified file is an ar archive
-/// by checking the magic string at the beginning of the file.
-///
-/// Inputs:
-/// filename - A C++ string containing the name of the file.
-///
-/// Outputs:
-/// None.
-///
-/// Return value:
-/// TRUE - The file is an archive.
-/// FALSE - The file is not an archive.
-///
-static inline bool IsArchive(const std::string &filename) {
- std::string ArchiveMagic("!<arch>\012");
- char buf[1 + ArchiveMagic.size()];
- std::ifstream f(filename.c_str());
- f.read(buf, ArchiveMagic.size());
- buf[ArchiveMagic.size()] = '\0';
- return ArchiveMagic == buf;
-}
-
-/// FindLib - locates a particular library. It will prepend and append
-/// various directories, prefixes, and suffixes until it can find the library.
-///
-/// Inputs:
-/// Filename - Name of the file to find.
-/// Paths - List of directories to search.
-///
-/// Outputs:
-/// None.
-///
-/// Return value:
-/// The name of the file is returned.
-/// If the file is not found, an empty string is returned.
-///
-static std::string
-FindLib(const std::string &Filename, const std::vector<std::string> &Paths) {
+using namespace llvm;
+
+/// FindLib - Try to convert Filename into the name of a file that we can open,
+/// if it does not already name a file we can open, by first trying to open
+/// Filename, then libFilename.[suffix] for each of a set of several common
+/// library suffixes, in each of the directories in Paths and the directory
+/// named by the value of the environment variable LLVM_LIB_SEARCH_PATH. Returns
+/// an empty string if no matching file can be found.
+///
+std::string llvm::FindLib(const std::string &Filename,
+ const std::vector<std::string> &Paths,
+ bool SharedObjectOnly) {
// Determine if the pathname can be found as it stands.
- if (FileExists(Filename))
+ if (FileOpenable(Filename))
return Filename;
// If that doesn't work, convert the name into a library name.
for (unsigned Index = 0; Index != Paths.size(); ++Index) {
std::string Directory = Paths[Index] + "/";
- if (FileExists(Directory + LibName + ".bc"))
+ if (!SharedObjectOnly && FileOpenable(Directory + LibName + ".bc"))
return Directory + LibName + ".bc";
- if (FileExists(Directory + LibName + ".so"))
- return Directory + LibName + ".so";
+ if (FileOpenable(Directory + LibName + LTDL_SHLIB_EXT))
+ return Directory + LibName + LTDL_SHLIB_EXT;
- if (FileExists(Directory + LibName + ".a"))
+ if (!SharedObjectOnly && FileOpenable(Directory + LibName + ".a"))
return Directory + LibName + ".a";
}
return std::string();
LibName = std::string(SearchPath) + "/" + LibName;
- if (FileExists(LibName))
+ if (FileOpenable(LibName))
return LibName;
return std::string();
}
-/// GetAllDefinedSymbols - finds all of the defined symbols in the specified
-/// module.
-///
-/// Inputs:
-/// M - The module in which to find defined symbols.
-///
-/// Outputs:
-/// DefinedSymbols - A set of C++ strings that will contain the name of all
-/// defined symbols.
-///
-/// Return value:
-/// None.
+/// GetAllDefinedSymbols - Modifies its parameter DefinedSymbols to contain the
+/// name of each externally-visible symbol defined in M.
///
-void GetAllDefinedSymbols(Module *M, std::set<std::string> &DefinedSymbols) {
+void llvm::GetAllDefinedSymbols(Module *M,
+ std::set<std::string> &DefinedSymbols) {
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (I->hasName() && !I->isExternal() && !I->hasInternalLinkage())
DefinedSymbols.insert(I->getName());
/// UndefinedSymbols - A set of C++ strings containing the name of all
/// undefined symbols.
///
-/// Return value:
-/// None.
-///
void
-GetAllUndefinedSymbols(Module *M, std::set<std::string> &UndefinedSymbols) {
+llvm::GetAllUndefinedSymbols(Module *M,
+ std::set<std::string> &UndefinedSymbols) {
std::set<std::string> DefinedSymbols;
- UndefinedSymbols.clear(); // Start out empty
+ UndefinedSymbols.clear();
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (I->hasName()) {
}
-/// LoadObject - reads the specified bytecode object file.
-///
-/// Inputs:
-/// FN - The name of the file to load.
+/// LoadObject - Read in and parse the bytecode file named by FN and return the
+/// module it contains (wrapped in an auto_ptr), or 0 and set ErrorMessage if an
+/// error occurs.
///
-/// Outputs:
-/// OutErrorMessage - The error message to give back to the caller.
-///
-/// Return Value:
-/// A pointer to a module represening the bytecode file is returned.
-/// If an error occurs, the pointer is 0.
-///
-std::auto_ptr<Module>
-LoadObject(const std::string & FN, std::string &OutErrorMessage) {
- std::string ErrorMessage;
- Module *Result = ParseBytecodeFile(FN, &ErrorMessage);
+static std::auto_ptr<Module> LoadObject(const std::string &FN,
+ std::string &ErrorMessage) {
+ std::string ParserErrorMessage;
+ Module *Result = ParseBytecodeFile(FN, &ParserErrorMessage);
if (Result) return std::auto_ptr<Module>(Result);
- OutErrorMessage = "Bytecode file '" + FN + "' corrupt!";
- if (ErrorMessage.size()) OutErrorMessage += ": " + ErrorMessage;
+ ErrorMessage = "Bytecode file '" + FN + "' could not be loaded";
+ if (ParserErrorMessage.size()) ErrorMessage += ": " + ParserErrorMessage;
return std::auto_ptr<Module>();
}
/// TRUE - An error occurred.
/// FALSE - No errors.
///
-static bool LinkInArchive(Module *M,
- const std::string &Filename,
- std::string &ErrorMessage,
- bool Verbose)
+bool llvm::LinkInArchive(Module *M,
+ const std::string &Filename,
+ std::string* ErrorMessage,
+ bool Verbose)
{
// Find all of the symbols currently undefined in the bytecode program.
// If all the symbols are defined, the program is complete, and there is
// no reason to link in any archive files.
std::set<std::string> UndefinedSymbols;
GetAllUndefinedSymbols(M, UndefinedSymbols);
+
if (UndefinedSymbols.empty()) {
if (Verbose) std::cerr << " No symbols undefined, don't link library!\n";
return false; // No need to link anything in!
}
- // Load in the archive objects.
- if (Verbose) std::cerr << " Loading '" << Filename << "'\n";
- std::vector<Module*> Objects;
- if (ReadArchiveFile(Filename, Objects, &ErrorMessage))
- return true;
-
- // Figure out which symbols are defined by all of the modules in the archive.
- std::vector<std::set<std::string> > DefinedSymbols;
- DefinedSymbols.resize(Objects.size());
- for (unsigned i = 0; i != Objects.size(); ++i) {
- GetAllDefinedSymbols(Objects[i], DefinedSymbols[i]);
- }
+ // Open the archive file
+ if (Verbose) std::cerr << " Loading archive file '" << Filename << "'\n";
+ std::auto_ptr<Archive> AutoArch (
+ Archive::OpenAndLoadSymbols(sys::Path(Filename)));
+
+ Archive* arch = AutoArch.get();
+
+ // Save a set of symbols that are not defined by the archive. Since we're
+ // entering a loop, there's no point searching for these multiple times. This
+ // variable is used to "set_subtract" from the set of undefined symbols.
+ std::set<std::string> NotDefinedByArchive;
// While we are linking in object files, loop.
- bool Linked = true;
- while (Linked) {
- Linked = false;
-
- for (unsigned i = 0; i != Objects.size(); ++i) {
- // Consider whether we need to link in this module... we only need to
- // link it in if it defines some symbol which is so far undefined.
- //
- const std::set<std::string> &DefSymbols = DefinedSymbols[i];
-
- bool ObjectRequired = false;
- for (std::set<std::string>::iterator I = UndefinedSymbols.begin(),
- E = UndefinedSymbols.end(); I != E; ++I)
- if (DefSymbols.count(*I)) {
- if (Verbose)
- std::cerr << " Found object providing symbol '" << *I << "'...\n";
- ObjectRequired = true;
- break;
- }
-
- // We DO need to link this object into the program...
- if (ObjectRequired) {
- if (LinkModules(M, Objects[i], &ErrorMessage))
- return true; // Couldn't link in the right object file...
-
- // Since we have linked in this object, delete it from the list of
- // objects to consider in this archive file.
- std::swap(Objects[i], Objects.back());
- std::swap(DefinedSymbols[i], DefinedSymbols.back());
- Objects.pop_back();
- DefinedSymbols.pop_back();
- --i; // Do not skip an entry
-
- // The undefined symbols set should have shrunk.
- GetAllUndefinedSymbols(M, UndefinedSymbols);
- Linked = true; // We have linked something in!
- }
+ while (true) {
+
+ // Find the modules we need to link into the target module
+ std::set<ModuleProvider*> Modules;
+ arch->findModulesDefiningSymbols(UndefinedSymbols, Modules);
+
+ // If we didn't find any more modules to link this time, we are done
+ // searching this archive.
+ if (Modules.empty())
+ break;
+
+ // Any symbols remaining in UndefinedSymbols after
+ // findModulesDefiningSymbols are ones that the archive does not define. So
+ // we add them to the NotDefinedByArchive variable now.
+ NotDefinedByArchive.insert(UndefinedSymbols.begin(),
+ UndefinedSymbols.end());
+
+ // Loop over all the ModuleProviders that we got back from the archive
+ for (std::set<ModuleProvider*>::iterator I=Modules.begin(), E=Modules.end();
+ I != E; ++I) {
+
+ // Get the module we must link in.
+ std::auto_ptr<Module> AutoModule( (*I)->releaseModule() );
+ Module* aModule = AutoModule.get();
+
+ // Link it in
+ if (LinkModules(M, aModule, ErrorMessage))
+ return true; // Couldn't link in the module
}
+
+ // Get the undefined symbols from the aggregate module. This recomputes the
+ // symbols we still need after the new modules have been linked in.
+ GetAllUndefinedSymbols(M, UndefinedSymbols);
+
+ // At this point we have two sets of undefined symbols: UndefinedSymbols
+ // which holds the undefined symbols from all the modules, and
+ // NotDefinedByArchive which holds symbols we know the archive doesn't
+ // define. There's no point searching for symbols that we won't find in the
+ // archive so we subtract these sets.
+ set_subtract<std::set<std::string>,std::set<std::string> >(
+ UndefinedSymbols,NotDefinedByArchive);
+
+ // If there's no symbols left, no point in continuing to search the
+ // archive.
+ if (UndefinedSymbols.empty())
+ break;
}
return false;
}
-/// LinkInFile - opens an archive library and link in all objects which
+/// LinkInFile - opens a bytecode file and links in all objects which
/// provide symbols that are currently undefined.
///
/// Inputs:
-/// HeadModule - The module in which to link the archives.
-/// Filename - The pathname of the archive.
+/// HeadModule - The module in which to link the bytecode file.
+/// Filename - The pathname of the bytecode file.
/// Verbose - Flags whether verbose messages should be printed.
///
/// Outputs:
{
std::auto_ptr<Module> M(LoadObject(Filename, ErrorMessage));
if (M.get() == 0) return true;
- if (Verbose) std::cerr << "Linking in '" << Filename << "'\n";
- return LinkModules(HeadModule, M.get(), &ErrorMessage);
+ bool Result = LinkModules(HeadModule, M.get(), &ErrorMessage);
+ if (Verbose) std::cerr << "Linked in bytecode file '" << Filename << "'\n";
+ return Result;
}
/// LinkFiles - takes a module and a list of files and links them all together.
/// FALSE - No errors.
/// TRUE - Some error occurred.
///
-bool LinkFiles(const char *progname,
- Module *HeadModule,
- const std::vector<std::string> &Files,
- bool Verbose)
-{
+bool llvm::LinkFiles(const char *progname, Module *HeadModule,
+ const std::vector<std::string> &Files, bool Verbose) {
// String in which to receive error messages.
std::string ErrorMessage;
// Get the library search path from the environment
char *SearchPath = getenv("LLVM_LIB_SEARCH_PATH");
- for (unsigned i = 1; i < Files.size(); ++i) {
+ for (unsigned i = 0; i < Files.size(); ++i) {
// Determine where this file lives.
- if (FileExists(Files[i])) {
+ if (FileOpenable(Files[i])) {
Pathname = Files[i];
} else {
if (SearchPath == NULL) {
std::cerr << progname << ": Cannot find linker input file '"
<< Files[i] << "'\n";
+ std::cerr << progname
+ << ": Warning: Your LLVM_LIB_SEARCH_PATH is unset.\n";
return true;
}
Pathname = std::string(SearchPath)+"/"+Files[i];
- if (!FileExists(Pathname)) {
+ if (!FileOpenable(Pathname)) {
std::cerr << progname << ": Cannot find linker input file '"
<< Files[i] << "'\n";
return true;
// is not installed as a library. Detect that and link the library.
if (IsArchive(Pathname)) {
if (Verbose)
- std::cerr << "Linking archive '" << Files[i] << "'\n";
+ std::cerr << "Trying to link archive '" << Pathname << "'\n";
- if (LinkInArchive(HeadModule, Pathname, ErrorMessage, Verbose)) {
- PrintAndReturn(progname, ErrorMessage,
- ": Error linking in '" + Files[i] + "'");
+ if (LinkInArchive(HeadModule, Pathname, &ErrorMessage, Verbose)) {
+ std::cerr << progname << ": Error linking in archive '" << Pathname
+ << "': " << ErrorMessage << "\n";
return true;
}
- } else {
+ } else if (IsBytecode(Pathname)) {
if (Verbose)
- std::cerr << "Linking file '" << Files[i] << "'\n";
+ std::cerr << "Trying to link bytecode file '" << Pathname << "'\n";
if (LinkInFile(HeadModule, Pathname, ErrorMessage, Verbose)) {
- PrintAndReturn(progname, ErrorMessage,
- ": Error linking in '" + Files[i] + "'");
+ std::cerr << progname << ": Error linking in bytecode file '"
+ << Pathname << "': " << ErrorMessage << "\n";
return true;
}
+ } else {
+ std::cerr << progname << ": Warning: invalid file `" << Pathname
+ << "' ignored.\n";
}
}
/// FALSE - No error.
/// TRUE - Error.
///
-bool LinkLibraries(const char *progname,
- Module *HeadModule,
- const std::vector<std::string> &Libraries,
- const std::vector<std::string> &LibPaths,
- bool Verbose,
- bool Native)
-{
+void llvm::LinkLibraries(const char *progname, Module *HeadModule,
+ const std::vector<std::string> &Libraries,
+ const std::vector<std::string> &LibPaths,
+ bool Verbose, bool Native) {
// String in which to receive error messages.
std::string ErrorMessage;
- for (unsigned i = 1; i < Libraries.size(); ++i) {
+ for (unsigned i = 0; i < Libraries.size(); ++i) {
// Determine where this library lives.
std::string Pathname = FindLib(Libraries[i], LibPaths);
if (Pathname.empty()) {
// we're doing a native link and give an error if we're doing a bytecode
// link.
if (!Native) {
- PrintAndReturn(progname, "Cannot find " + Libraries[i] + "\n");
- return true;
+ std::cerr << progname << ": WARNING: Cannot find library -l"
+ << Libraries[i] << "\n";
+ continue;
}
}
// is not installed as a library. Detect that and link the library.
if (IsArchive(Pathname)) {
if (Verbose)
- std::cerr << "Linking archive '" << Libraries[i] << "'\n";
-
- if (LinkInArchive(HeadModule, Pathname, ErrorMessage, Verbose)) {
- PrintAndReturn(progname, ErrorMessage,
- ": Error linking in '" + Libraries[i] + "'");
- return true;
+ std::cerr << "Trying to link archive '" << Pathname << "' (-l"
+ << Libraries[i] << ")\n";
+
+ if (LinkInArchive(HeadModule, Pathname, &ErrorMessage, Verbose)) {
+ std::cerr << progname << ": " << ErrorMessage
+ << ": Error linking in archive '" << Pathname << "' (-l"
+ << Libraries[i] << ")\n";
+ exit(1);
}
- } else {
+ } else if (IsBytecode(Pathname)) {
if (Verbose)
- std::cerr << "Linking file '" << Libraries[i] << "'\n";
+ std::cerr << "Trying to link bytecode file '" << Pathname
+ << "' (-l" << Libraries[i] << ")\n";
if (LinkInFile(HeadModule, Pathname, ErrorMessage, Verbose)) {
- PrintAndReturn(progname, ErrorMessage,
- ": error linking in '" + Libraries[i] + "'");
- return true;
+ std::cerr << progname << ": " << ErrorMessage
+ << ": error linking in bytecode file '" << Pathname << "' (-l"
+ << Libraries[i] << ")\n";
+ exit(1);
}
}
}
-
- return false;
}