Initial implementation of llvm-ld: stolen from gccld.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16305 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-ld/llvm-ld.cpp b/tools/llvm-ld/llvm-ld.cpp
new file mode 100644
index 0000000..d59b18a
--- /dev/null
+++ b/tools/llvm-ld/llvm-ld.cpp
@@ -0,0 +1,303 @@
+//===- llvm-ld.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 "llvm-ld.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/Linker.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;
+
+enum OptimizationLevels {
+ OPT_FAST_COMPILE,
+ OPT_SIMPLE,
+ OPT_AGGRESSIVE,
+ OPT_LINK_TIME,
+ OPT_AGGRESSIVE_LINK_TIME
+};
+
+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("s", cl::desc("Strip 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::desc("Generate a native binary instead of a shell script"));
+ cl::opt<bool>
+ NativeCBE("native-cbe",
+ cl::desc("Generate a native binary with the C backend and GCC"));
+
+ // Compatibility options that are ignored but supported by LD
+ cl::opt<std::string>
+ CO3("soname", cl::Hidden, cl::desc("Compatibility option: ignored"));
+ 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<OptimizationLevels> OptLevel(
+ cl::desc("Choose level of optimization to apply:"),
+ cl::init(OPT_FAST_COMPILE), cl::values(
+ clEnumValN(OPT_FAST_COMPILE,"O0",
+ "An alias for the -O1 option."),
+ clEnumValN(OPT_FAST_COMPILE,"O1",
+ "Optimize for linking speed, not execution speed."),
+ clEnumValN(OPT_SIMPLE,"O2",
+ "Perform only required/minimal optimizations"),
+ clEnumValN(OPT_AGGRESSIVE,"O3",
+ "An alias for the -O2 option."),
+ clEnumValN(OPT_LINK_TIME,"O4",
+ "Perform standard link time optimizations"),
+ clEnumValN(OPT_AGGRESSIVE_LINK_TIME,"O5",
+ "Perform aggressive link time optimizations"),
+ clEnumValEnd
+ )
+ );
+}
+
+/// 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]);
+ if (llvmstub.empty()) {
+ std::cerr << "Could not find llvm-stub.exe executable!\n";
+ exit(1);
+ }
+ if (CopyFile(OutputFilename, llvmstub)) {
+ std::cerr << "Could not copy the llvm-stub.exe executable!\n";
+ exit(1);
+ }
+ 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";
+ // gcc accepts -l<lib> and implicitly searches /lib and /usr/lib.
+ LibPaths.push_back("/lib");
+ LibPaths.push_back("/usr/lib");
+ LibPaths.push_back("/usr/X11R6/lib");
+ // 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) {
+ std::string FullLibraryPath = FindLib(*i, LibPaths, true);
+ if (!FullLibraryPath.empty() && IsSharedObject(FullLibraryPath))
+ Out2 << " -load=" << FullLibraryPath << " \\\n";
+ }
+ Out2 << " $0.bc ${1+\"$@\"}\n";
+ Out2.close();
+}
+
+int main(int argc, char **argv, char **envp) {
+ cl::ParseCommandLineOptions(argc, argv, " llvm linker for GCC\n");
+ sys::PrintStackTraceOnErrorSignal();
+
+ std::string ModuleID("gccld-output");
+ std::auto_ptr<Module> Composite(new Module(ModuleID));
+
+ // We always look first in the current directory when searching for libraries.
+ LibPaths.insert(LibPaths.begin(), ".");
+
+ // If the user specified an extra search path in their environment, respect
+ // it.
+ if (char *SearchPath = getenv("LLVM_LIB_SEARCH_PATH"))
+ LibPaths.push_back(SearchPath);
+
+ // Remove any consecutive duplicates of the same library...
+ Libraries.erase(std::unique(Libraries.begin(), Libraries.end()),
+ Libraries.end());
+
+ // Link in all of the files
+ if (LinkFiles(argv[0], Composite.get(), InputFilenames, Verbose))
+ return 1; // Error already printed
+
+ if (!LinkAsLibrary)
+ LinkLibraries(argv[0], Composite.get(), Libraries, LibPaths,
+ Verbose, Native);
+
+ // Link in all of the libraries next...
+
+ // Create the output file.
+ std::string RealBytecodeOutput = OutputFilename;
+ if (!LinkAsLibrary) RealBytecodeOutput += ".bc";
+ std::ofstream Out(RealBytecodeOutput.c_str());
+ 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(RealBytecodeOutput);
+
+ // Generate the bytecode file.
+ if (GenerateBytecode(Composite.get(), Strip, !NoInternalize, &Out)) {
+ Out.close();
+ return PrintAndReturn(argv[0], "error generating bytecode");
+ }
+
+ // Close the bytecode file.
+ Out.close();
+
+ // If we are not linking a library, generate either a native executable
+ // or a JIT shell script, depending upon what the user wants.
+ if (!LinkAsLibrary) {
+ // If the user wants to generate a native executable, compile it from the
+ // bytecode file.
+ //
+ // Otherwise, create a script that will run the bytecode through the JIT.
+ if (Native) {
+ // Name of the Assembly Language output file
+ std::string AssemblyFile = OutputFilename + ".s";
+
+ // Mark the output files for removal if we get an interrupt.
+ sys::RemoveFileOnSignal(AssemblyFile);
+ sys::RemoveFileOnSignal(OutputFilename);
+
+ // Determine the locations of the llc and gcc programs.
+ std::string llc = FindExecutable("llc", argv[0]);
+ std::string gcc = FindExecutable("gcc", argv[0]);
+ if (llc.empty())
+ return PrintAndReturn(argv[0], "Failed to find llc");
+
+ if (gcc.empty())
+ 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, RealBytecodeOutput, llc, envp);
+ if (Verbose) std::cout << "Generating Native Code\n";
+ GenerateNative(OutputFilename, AssemblyFile, Libraries, LibPaths,
+ gcc, envp);
+
+ // Remove the assembly language file.
+ removeFile (AssemblyFile);
+ } else if (NativeCBE) {
+ std::string CFile = OutputFilename + ".cbe.c";
+
+ // Mark the output files for removal if we get an interrupt.
+ sys::RemoveFileOnSignal(CFile);
+ sys::RemoveFileOnSignal(OutputFilename);
+
+ // Determine the locations of the llc and gcc programs.
+ std::string llc = FindExecutable("llc", argv[0]);
+ std::string gcc = FindExecutable("gcc", argv[0]);
+ if (llc.empty())
+ return PrintAndReturn(argv[0], "Failed to find llc");
+ if (gcc.empty())
+ return PrintAndReturn(argv[0], "Failed to find gcc");
+
+ // Generate an assembly language file for the bytecode.
+ if (Verbose) std::cout << "Generating Assembly Code\n";
+ GenerateCFile(CFile, RealBytecodeOutput, llc, envp);
+ if (Verbose) std::cout << "Generating Native Code\n";
+ GenerateNative(OutputFilename, CFile, Libraries, LibPaths, gcc, envp);
+
+ // Remove the assembly language file.
+ removeFile(CFile);
+
+ } else {
+ EmitShellScript(argv);
+ }
+
+ // Make the script executable...
+ MakeFileExecutable(OutputFilename);
+
+ // Make the bytecode file readable and directly executable in LLEE as well
+ MakeFileExecutable(RealBytecodeOutput);
+ MakeFileReadable(RealBytecodeOutput);
+ }
+
+ return 0;
+}