llvm-6502/lib/Linker/LinkItems.cpp
Reid Spencer 4952143236 For PR998:
Fix an infinite loop in the Linker and a few other assorted link problems.

Patch contributed by Scott Michel. Thanks, Scott!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31680 91177308-0d34-0410-b5e6-96231b3b80d8
2006-11-11 11:54:25 +00:00

183 lines
6.2 KiB
C++

//===- lib/Linker/LinkItems.cpp - Link LLVM objects and libraries ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Reid Spencer and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains routines to handle linking together LLVM bytecode files,
// and to handle annoying things like static libraries.
//
//===----------------------------------------------------------------------===//
#include "llvm/Linker.h"
#include "llvm/Module.h"
using namespace llvm;
// LinkItems - This function is the main entry point into linking. It takes a
// list of LinkItem which indicates the order the files should be linked and
// how each file should be treated (plain file or with library search). The
// function only links bytecode and produces a result list of items that are
// native objects.
bool
Linker::LinkInItems(const ItemList& Items, ItemList& NativeItems) {
// Clear the NativeItems just in case
NativeItems.clear();
// For each linkage item ...
for (ItemList::const_iterator I = Items.begin(), E = Items.end();
I != E; ++I) {
if (I->second) {
// Link in the library suggested.
bool is_bytecode = true;
if (LinkInLibrary(I->first,is_bytecode))
return true;
if (!is_bytecode)
NativeItems.push_back(*I);
} else {
// Link in the file suggested
if (LinkInFile(sys::Path(I->first)))
return true;
}
}
// At this point we have processed all the link items provided to us. Since
// we have an aggregated module at this point, the dependent libraries in
// that module should also be aggregated with duplicates eliminated. This is
// now the time to process the dependent libraries to resolve any remaining
// symbols.
bool is_bytecode;
for (Module::lib_iterator I = Composite->lib_begin(),
E = Composite->lib_end(); I != E; ++I)
if(LinkInLibrary(*I, is_bytecode))
return true;
return false;
}
/// LinkInLibrary - links one library into the HeadModule.
///
bool Linker::LinkInLibrary(const std::string& Lib, bool& is_bytecode) {
is_bytecode = false;
// Determine where this library lives.
sys::Path Pathname = FindLib(Lib);
if (Pathname.isEmpty())
return warning("Cannot find library '" + Lib + "'");
// If its an archive, try to link it in
std::string Magic;
Pathname.getMagicNumber(Magic, 64);
switch (sys::IdentifyFileType(Magic.c_str(), 64)) {
case sys::BytecodeFileType:
case sys::CompressedBytecodeFileType:
// LLVM ".so" file.
if (LinkInFile(Pathname))
return error("Cannot link file '" + Pathname.toString() + "'");
is_bytecode = true;
break;
case sys::ArchiveFileType:
if (LinkInArchive(Pathname))
return error("Cannot link archive '" + Pathname.toString() + "'");
is_bytecode = true;
break;
default:
return warning("Supposed library '" + Lib + "' isn't a library.");
}
return false;
}
/// LinkLibraries - takes the specified library files and links them into the
/// main bytecode object file.
///
/// Inputs:
/// Libraries - The list of libraries to link into the module.
///
/// Return value:
/// FALSE - No error.
/// TRUE - Error.
///
bool Linker::LinkInLibraries(const std::vector<std::string> &Libraries) {
// Process the set of libraries we've been provided.
bool is_bytecode;
for (unsigned i = 0; i < Libraries.size(); ++i)
if (LinkInLibrary(Libraries[i], is_bytecode))
return true;
// At this point we have processed all the libraries provided to us. Since
// we have an aggregated module at this point, the dependent libraries in
// that module should also be aggregated with duplicates eliminated. This is
// now the time to process the dependent libraries to resolve any remaining
// symbols.
const Module::LibraryListType& DepLibs = Composite->getLibraries();
for (Module::LibraryListType::const_iterator I = DepLibs.begin(),
E = DepLibs.end(); I != E; ++I)
if (LinkInLibrary(*I, is_bytecode))
return true;
return false;
}
/// LinkInFile - opens a bytecode file and links in all objects which
/// provide symbols that are currently undefined.
///
/// Inputs:
/// File - The pathname of the bytecode file.
///
/// Outputs:
/// ErrorMessage - A C++ string detailing what error occurred, if any.
///
/// Return Value:
/// TRUE - An error occurred.
/// FALSE - No errors.
///
bool Linker::LinkInFile(const sys::Path &File) {
// Make sure we can at least read the file
if (!File.canRead())
return error("Cannot find linker input '" + File.toString() + "'");
// A user may specify an ar archive without -l, perhaps because it
// is not installed as a library. Detect that and link the library.
if (File.isArchive()) {
if (LinkInArchive(File))
return error("Cannot link archive '" + File.toString() + "'");
} else if (File.isBytecodeFile()) {
verbose("Linking bytecode file '" + File.toString() + "'");
std::auto_ptr<Module> M(LoadObject(File));
if (M.get() == 0)
return error("Cannot load file '" + File.toString() + "'" + Error);
if (LinkInModule(M.get()))
return error("Cannot link file '" + File.toString() + "'" + Error);
verbose("Linked in file '" + File.toString() + "'");
} else {
return warning("File of unknown type '" + File.toString() + "' ignored.");
}
return false;
}
/// LinkFiles - takes a module and a list of files and links them all together.
/// It locates the file either in the current directory, as its absolute
/// or relative pathname, or as a file somewhere in LLVM_LIB_SEARCH_PATH.
///
/// Inputs:
/// Files - A vector of sys::Path indicating the LLVM bytecode filenames
/// to be linked. The names can refer to a mixture of pure LLVM
/// bytecode files and archive (ar) formatted files.
///
/// Return value:
/// FALSE - No errors.
/// TRUE - Some error occurred.
///
bool Linker::LinkInFiles(const std::vector<sys::Path> &Files) {
for (unsigned i = 0; i < Files.size(); ++i)
if (LinkInFile(Files[i]))
return true;
return false;
}