llvm-6502/tools/gccld/gccld.cpp
Reid Spencer f4484f3e16 For PR521:
With these patches we implement the ability for the Linker library to
keep track of which libraries were actually bytecode files (not archives)
and cause their users to remove such files from the list of libraries to
pass to the native linker.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25169 91177308-0d34-0410-b5e6-96231b3b80d8
2006-01-10 03:14:40 +00:00

394 lines
14 KiB
C++

//===- gccld.cpp - LLVM 'ld' compatible linker ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This utility is intended to be compatible with GCC, and follows standard
// system 'ld' conventions. As such, the default output file is ./a.out.
// Additionally, this program outputs a shell script that is used to invoke LLI
// to execute the program. In this manner, the generated executable (a.out for
// example), is directly executable, whereas the bytecode file actually lives in
// the a.out.bc file generated by this program. Also, Force is on by default.
//
// Note that if someone (or a script) deletes the executable program generated,
// the .bc file will be left around. Considering that this is a temporary hack,
// I'm not too worried about this.
//
//===----------------------------------------------------------------------===//
#include "gccld.h"
#include "llvm/Linker.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Bytecode/Reader.h"
#include "llvm/Bytecode/WriteBytecodePass.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/System/Signals.h"
#include "llvm/Support/SystemUtils.h"
#include <fstream>
#include <memory>
using namespace llvm;
namespace {
cl::list<std::string>
InputFilenames(cl::Positional, cl::desc("<input bytecode files>"),
cl::OneOrMore);
cl::opt<std::string>
OutputFilename("o", cl::desc("Override output filename"), cl::init("a.out"),
cl::value_desc("filename"));
cl::opt<bool>
Verbose("v", cl::desc("Print information about actions taken"));
cl::list<std::string>
LibPaths("L", cl::desc("Specify a library search path"), cl::Prefix,
cl::value_desc("directory"));
cl::list<std::string>
Libraries("l", cl::desc("Specify libraries to link to"), cl::Prefix,
cl::value_desc("library prefix"));
cl::opt<bool>
Strip("strip-all", cl::desc("Strip all symbol info from executable"));
cl::opt<bool>
StripDebug("strip-debug",
cl::desc("Strip debugger symbol info from executable"));
cl::opt<bool>
NoInternalize("disable-internalize",
cl::desc("Do not mark all symbols as internal"));
cl::alias
ExportDynamic("export-dynamic", cl::desc("Alias for -disable-internalize"),
cl::aliasopt(NoInternalize));
cl::opt<bool>
LinkAsLibrary("link-as-library", cl::desc("Link the .bc files together as a"
" library, not an executable"));
cl::alias
Relink("r", cl::desc("Alias for -link-as-library"),
cl::aliasopt(LinkAsLibrary));
cl::opt<bool>
Native("native", cl::ZeroOrMore,
cl::desc("Generate a native binary instead of a shell script"));
cl::opt<bool>
NativeCBE("native-cbe", cl::ZeroOrMore,
cl::desc("Generate a native binary with the C backend and GCC"));
cl::opt<bool>
SaveTemps("save-temps",
cl::desc("Do not delete temporary files"));
cl::list<std::string>
RPath("rpath",
cl::desc("Set runtime shared library search path (requires -native or"
" -native-cbe)"),
cl::Prefix, cl::value_desc("directory"));
cl::opt<std::string>
SOName("soname",
cl::desc("Set internal name of shared library (requires -native or"
" -native-cbe)"),
cl::Prefix, cl::value_desc("name"));
// Compatibility options that are ignored but supported by LD
cl::opt<std::string>
CO4("version-script", cl::Hidden, cl::desc("Compatibility option: ignored"));
cl::opt<bool>
CO5("eh-frame-hdr", cl::Hidden, cl::desc("Compatibility option: ignored"));
cl::opt<std::string>
CO6("h", cl::Hidden, cl::desc("Compatibility option: ignored"));
cl::opt<bool>
CO7("start-group", cl::Hidden, cl::desc("Compatibility option: ignored"));
cl::opt<bool>
CO8("end-group", cl::Hidden, cl::desc("Compatibility option: ignored"));
cl::alias A0("s", cl::desc("Alias for --strip-all"),
cl::aliasopt(Strip));
cl::alias A1("S", cl::desc("Alias for --strip-debug"),
cl::aliasopt(StripDebug));
}
/// PrintAndReturn - Prints a message to standard error and returns true.
///
/// Inputs:
/// progname - The name of the program (i.e. argv[0]).
/// Message - The message to print to standard error.
///
static int PrintAndReturn(const char *progname, const std::string &Message) {
std::cerr << progname << ": " << Message << "\n";
return 1;
}
/// EmitShellScript - Output the wrapper file that invokes the JIT on the LLVM
/// bytecode file for the program.
static void EmitShellScript(char **argv) {
#if defined(_WIN32) || defined(__CYGWIN__)
// Windows doesn't support #!/bin/sh style shell scripts in .exe files. To
// support windows systems, we copy the llvm-stub.exe executable from the
// build tree to the destination file.
std::string llvmstub = FindExecutable("llvm-stub.exe", argv[0]).toString();
if (llvmstub.empty()) {
std::cerr << "Could not find llvm-stub.exe executable!\n";
exit(1);
}
sys::CopyFile(sys::Path(OutputFilename), sys::Path(llvmstub));
return;
#endif
// Output the script to start the program...
std::ofstream Out2(OutputFilename.c_str());
if (!Out2.good())
exit(PrintAndReturn(argv[0], "error opening '" + OutputFilename +
"' for writing!"));
Out2 << "#!/bin/sh\n";
// Allow user to setenv LLVMINTERP if lli is not in their PATH.
Out2 << "lli=${LLVMINTERP-lli}\n";
Out2 << "exec $lli \\\n";
// We don't need to link in libc! In fact, /usr/lib/libc.so may not be a
// shared object at all! See RH 8: plain text.
std::vector<std::string>::iterator libc =
std::find(Libraries.begin(), Libraries.end(), "c");
if (libc != Libraries.end()) Libraries.erase(libc);
// List all the shared object (native) libraries this executable will need
// on the command line, so that we don't have to do this manually!
for (std::vector<std::string>::iterator i = Libraries.begin(),
e = Libraries.end(); i != e; ++i) {
sys::Path FullLibraryPath = sys::Path::FindLibrary(*i);
if (!FullLibraryPath.isEmpty() && FullLibraryPath.isDynamicLibrary())
Out2 << " -load=" << FullLibraryPath.toString() << " \\\n";
}
Out2 << " $0.bc ${1+\"$@\"}\n";
Out2.close();
}
// BuildLinkItems -- This function generates a LinkItemList for the LinkItems
// linker function by combining the Files and Libraries in the order they were
// declared on the command line.
static void BuildLinkItems(
Linker::ItemList& Items,
const cl::list<std::string>& Files,
const cl::list<std::string>& Libraries) {
// Build the list of linkage items for LinkItems.
cl::list<std::string>::const_iterator fileIt = Files.begin();
cl::list<std::string>::const_iterator libIt = Libraries.begin();
int libPos = -1, filePos = -1;
while ( libIt != Libraries.end() || fileIt != Files.end() ) {
if (libIt != Libraries.end())
libPos = Libraries.getPosition(libIt - Libraries.begin());
else
libPos = -1;
if (fileIt != Files.end())
filePos = Files.getPosition(fileIt - Files.begin());
else
filePos = -1;
if (filePos != -1 && (libPos == -1 || filePos < libPos)) {
// Add a source file
Items.push_back(std::make_pair(*fileIt++, false));
} else if (libPos != -1 && (filePos == -1 || libPos < filePos)) {
// Add a library
Items.push_back(std::make_pair(*libIt++, true));
}
}
}
int main(int argc, char **argv, char **envp ) {
cl::ParseCommandLineOptions(argc, argv, " llvm linker for GCC\n");
sys::PrintStackTraceOnErrorSignal();
int exitCode = 0;
std::string ProgName = sys::Path(argv[0]).getBasename();
Linker TheLinker(ProgName, OutputFilename, Verbose);
try {
// Remove any consecutive duplicates of the same library...
Libraries.erase(std::unique(Libraries.begin(), Libraries.end()),
Libraries.end());
TheLinker.addPaths(LibPaths);
TheLinker.addSystemPaths();
if (LinkAsLibrary) {
std::vector<sys::Path> Files;
for (unsigned i = 0; i < InputFilenames.size(); ++i )
Files.push_back(sys::Path(InputFilenames[i]));
if (TheLinker.LinkInFiles(Files))
return 1; // Error already printed by linker
// The libraries aren't linked in but are noted as "dependent" in the
// module.
for (cl::list<std::string>::const_iterator I = Libraries.begin(),
E = Libraries.end(); I != E ; ++I) {
TheLinker.getModule()->addLibrary(*I);
}
} else {
// Build a list of the items from our command line
Linker::ItemList Items;
Linker::ItemList NativeItems;
BuildLinkItems(Items, InputFilenames, Libraries);
// Link all the items together
if (TheLinker.LinkInItems(Items,NativeItems))
return 1; // Error already printed
// Revise the Libraries based on the remaining (native) libraries that
// were not linked in to the bytecode. This ensures that we don't attempt
// to pass a bytecode library to the native linker
Libraries.clear(); // we've consumed the libraries except for native
if ((Native || NativeCBE) && !NativeItems.empty()) {
for (Linker::ItemList::const_iterator I = NativeItems.begin(),
E = NativeItems.end(); I != E; ++I) {
Libraries.push_back(I->first);
}
}
}
// We're done with the Linker, so tell it to release its module
std::auto_ptr<Module> Composite(TheLinker.releaseModule());
// Create the output file.
std::string RealBytecodeOutput = OutputFilename;
if (!LinkAsLibrary || Native || NativeCBE) RealBytecodeOutput += ".bc";
std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
std::ios::binary;
std::ofstream Out(RealBytecodeOutput.c_str(), io_mode);
if (!Out.good())
return PrintAndReturn(argv[0], "error opening '" + RealBytecodeOutput +
"' for writing!");
// Ensure that the bytecode file gets removed from the disk if we get a
// SIGINT signal.
sys::RemoveFileOnSignal(sys::Path(RealBytecodeOutput));
// Strip everything if Strip is set, otherwise if stripdebug is set, just
// strip debug info.
int StripLevel = Strip ? 2 : (StripDebug ? 1 : 0);
// Internalize the module if neither -disable-internalize nor
// -link-as-library are passed in.
bool ShouldInternalize = !NoInternalize & !LinkAsLibrary;
// Generate the bytecode file.
if (GenerateBytecode(Composite.get(), StripLevel, ShouldInternalize, &Out)){
Out.close();
return PrintAndReturn(argv[0], "error generating bytecode");
}
// Close the bytecode file.
Out.close();
// Generate either a native file or a JIT shell script. If the user wants
// to generate a native file, compile it from the bytecode file. Otherwise,
// if the target is not a library, create a script that will run the
// bytecode through the JIT.
if (Native) {
// Name of the Assembly Language output file
sys::Path AssemblyFile (OutputFilename);
AssemblyFile.appendSuffix("s");
// Mark the output files for removal if we get an interrupt.
sys::RemoveFileOnSignal(AssemblyFile);
sys::RemoveFileOnSignal(sys::Path(OutputFilename));
// Determine the locations of the llc and gcc programs.
sys::Path llc = FindExecutable("llc", argv[0]);
if (llc.isEmpty())
return PrintAndReturn(argv[0], "Failed to find llc");
sys::Path gcc = FindExecutable("gcc", argv[0]);
if (gcc.isEmpty())
return PrintAndReturn(argv[0], "Failed to find gcc");
// Generate an assembly language file for the bytecode.
if (Verbose) std::cout << "Generating Assembly Code\n";
GenerateAssembly(AssemblyFile.toString(), RealBytecodeOutput, llc,
Verbose);
if (Verbose) std::cout << "Generating Native Code\n";
GenerateNative(OutputFilename, AssemblyFile.toString(),
LibPaths, Libraries, gcc, envp, LinkAsLibrary,
NoInternalize, RPath, SOName, Verbose);
if (!SaveTemps) {
// Remove the assembly language file.
AssemblyFile.eraseFromDisk();
// Remove the bytecode language file.
sys::Path(RealBytecodeOutput).eraseFromDisk();
}
} else if (NativeCBE) {
sys::Path CFile (OutputFilename);
CFile.appendSuffix("cbe.c");
// Mark the output files for removal if we get an interrupt.
sys::RemoveFileOnSignal(CFile);
sys::RemoveFileOnSignal(sys::Path(OutputFilename));
// Determine the locations of the llc and gcc programs.
sys::Path llc = FindExecutable("llc", argv[0]);
if (llc.isEmpty())
return PrintAndReturn(argv[0], "Failed to find llc");
sys::Path gcc = FindExecutable("gcc", argv[0]);
if (gcc.isEmpty())
return PrintAndReturn(argv[0], "Failed to find gcc");
// Generate an assembly language file for the bytecode.
if (Verbose) std::cout << "Generating C Source Code\n";
GenerateCFile(CFile.toString(), RealBytecodeOutput, llc, Verbose);
if (Verbose) std::cout << "Generating Native Code\n";
GenerateNative(OutputFilename, CFile.toString(),
LibPaths, Libraries, gcc, envp, LinkAsLibrary,
NoInternalize, RPath, SOName, Verbose);
if (!SaveTemps) {
// Remove the assembly language file.
CFile.eraseFromDisk();
// Remove the bytecode language file.
sys::Path(RealBytecodeOutput).eraseFromDisk();
}
} else if (!LinkAsLibrary) {
EmitShellScript(argv);
// Make the bytecode file readable and directly executable in LLEE
sys::Path(RealBytecodeOutput).makeExecutableOnDisk();
sys::Path(RealBytecodeOutput).makeReadableOnDisk();
}
// Make the output, whether native or script, executable as well...
sys::Path(OutputFilename).makeExecutableOnDisk();
} catch (const char*msg) {
std::cerr << argv[0] << ": " << msg << "\n";
exitCode = 1;
} catch (const std::string& msg) {
std::cerr << argv[0] << ": " << msg << "\n";
exitCode = 2;
} catch (...) {
// This really shouldn't happen, but just in case ....
std::cerr << argv[0] << ": An unexpected unknown exception occurred.\n";
exitCode = 3;
}
return exitCode;
}