1 //===- gccld.cpp - LLVM 'ld' compatible linker ----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This utility is intended to be compatible with GCC, and follows standard
11 // system 'ld' conventions. As such, the default output file is ./a.out.
12 // Additionally, this program outputs a shell script that is used to invoke LLI
13 // to execute the program. In this manner, the generated executable (a.out for
14 // example), is directly executable, whereas the bytecode file actually lives in
15 // the a.out.bc file generated by this program. Also, Force is on by default.
17 // Note that if someone (or a script) deletes the executable program generated,
18 // the .bc file will be left around. Considering that this is a temporary hack,
19 // I'm not too worried about this.
21 //===----------------------------------------------------------------------===//
24 #include "llvm/Linker.h"
25 #include "llvm/Module.h"
26 #include "llvm/PassManager.h"
27 #include "llvm/Bytecode/Reader.h"
28 #include "llvm/Bytecode/WriteBytecodePass.h"
29 #include "llvm/Target/TargetData.h"
30 #include "llvm/Transforms/IPO.h"
31 #include "llvm/Transforms/Scalar.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/FileUtilities.h"
34 #include "llvm/System/Signals.h"
35 #include "llvm/Support/SystemUtils.h"
42 InputFilenames(cl::Positional, cl::desc("<input bytecode files>"),
46 OutputFilename("o", cl::desc("Override output filename"), cl::init("a.out"),
47 cl::value_desc("filename"));
50 Verbose("v", cl::desc("Print information about actions taken"));
53 LibPaths("L", cl::desc("Specify a library search path"), cl::Prefix,
54 cl::value_desc("directory"));
57 Libraries("l", cl::desc("Specify libraries to link to"), cl::Prefix,
58 cl::value_desc("library prefix"));
61 Strip("strip-all", cl::desc("Strip all symbol info from executable"));
63 StripDebug("strip-debug",
64 cl::desc("Strip debugger symbol info from executable"));
67 NoInternalize("disable-internalize",
68 cl::desc("Do not mark all symbols as internal"));
70 ExportDynamic("export-dynamic", cl::desc("Alias for -disable-internalize"),
71 cl::aliasopt(NoInternalize));
74 LinkAsLibrary("link-as-library", cl::desc("Link the .bc files together as a"
75 " library, not an executable"));
77 Relink("r", cl::desc("Alias for -link-as-library"),
78 cl::aliasopt(LinkAsLibrary));
82 cl::desc("Generate a native binary instead of a shell script"));
84 NativeCBE("native-cbe",
85 cl::desc("Generate a native binary with the C backend and GCC"));
87 // Compatibility options that are ignored but supported by LD
89 CO3("soname", cl::Hidden, cl::desc("Compatibility option: ignored"));
91 CO4("version-script", cl::Hidden, cl::desc("Compatibility option: ignored"));
93 CO5("eh-frame-hdr", cl::Hidden, cl::desc("Compatibility option: ignored"));
95 CO6("h", cl::Hidden, cl::desc("Compatibility option: ignored"));
97 cl::alias A0("s", cl::desc("Alias for --strip-all"),
99 cl::alias A1("S", cl::desc("Alias for --strip-debug"),
100 cl::aliasopt(StripDebug));
103 /// PrintAndReturn - Prints a message to standard error and returns true.
106 /// progname - The name of the program (i.e. argv[0]).
107 /// Message - The message to print to standard error.
109 static int PrintAndReturn(const char *progname, const std::string &Message) {
110 std::cerr << progname << ": " << Message << "\n";
114 /// EmitShellScript - Output the wrapper file that invokes the JIT on the LLVM
115 /// bytecode file for the program.
116 static void EmitShellScript(char **argv) {
117 #if defined(_WIN32) || defined(__CYGWIN__)
118 // Windows doesn't support #!/bin/sh style shell scripts in .exe files. To
119 // support windows systems, we copy the llvm-stub.exe executable from the
120 // build tree to the destination file.
121 std::string llvmstub = FindExecutable("llvm-stub.exe", argv[0]);
122 if (llvmstub.empty()) {
123 std::cerr << "Could not find llvm-stub.exe executable!\n";
126 if (CopyFile(OutputFilename, llvmstub)) {
127 std::cerr << "Could not copy the llvm-stub.exe executable!\n";
133 // Output the script to start the program...
134 std::ofstream Out2(OutputFilename.c_str());
136 exit(PrintAndReturn(argv[0], "error opening '" + OutputFilename +
139 Out2 << "#!/bin/sh\n";
140 // Allow user to setenv LLVMINTERP if lli is not in their PATH.
141 Out2 << "lli=${LLVMINTERP-lli}\n";
142 Out2 << "exec $lli \\\n";
143 // gcc accepts -l<lib> and implicitly searches /lib and /usr/lib.
144 LibPaths.push_back("/lib");
145 LibPaths.push_back("/usr/lib");
146 LibPaths.push_back("/usr/X11R6/lib");
147 // We don't need to link in libc! In fact, /usr/lib/libc.so may not be a
148 // shared object at all! See RH 8: plain text.
149 std::vector<std::string>::iterator libc =
150 std::find(Libraries.begin(), Libraries.end(), "c");
151 if (libc != Libraries.end()) Libraries.erase(libc);
152 // List all the shared object (native) libraries this executable will need
153 // on the command line, so that we don't have to do this manually!
154 for (std::vector<std::string>::iterator i = Libraries.begin(),
155 e = Libraries.end(); i != e; ++i) {
156 std::string FullLibraryPath = FindLib(*i, LibPaths, true);
157 if (!FullLibraryPath.empty() && IsSharedObject(FullLibraryPath))
158 Out2 << " -load=" << FullLibraryPath << " \\\n";
160 Out2 << " $0.bc ${1+\"$@\"}\n";
164 int main(int argc, char **argv, char **envp) {
165 cl::ParseCommandLineOptions(argc, argv, " llvm linker for GCC\n");
166 sys::PrintStackTraceOnErrorSignal();
171 // Remove any consecutive duplicates of the same library...
172 Libraries.erase(std::unique(Libraries.begin(), Libraries.end()),
175 // Set up the Composite module.
176 std::auto_ptr<Module> Composite(0);
179 // Link in only the files, we ignore libraries in this case.
180 Composite.reset( new Module(argv[0]) );
181 if (LinkFiles(argv[0], Composite.get(), InputFilenames, Verbose))
182 return 1; // Error already printed
184 // Build a list of the items from our command line
186 BuildLinkItems(Items, InputFilenames, Libraries);
188 // Link all the items together
189 Composite.reset( LinkItems(argv[0], Items, LibPaths, Verbose, Native) );
191 // Check for an error during linker
192 if (!Composite.get())
193 return 1; // Error already printed
196 // Create the output file.
197 std::string RealBytecodeOutput = OutputFilename;
198 if (!LinkAsLibrary) RealBytecodeOutput += ".bc";
199 std::ofstream Out(RealBytecodeOutput.c_str());
201 return PrintAndReturn(argv[0], "error opening '" + RealBytecodeOutput +
204 // Ensure that the bytecode file gets removed from the disk if we get a
206 sys::RemoveFileOnSignal(sys::Path(RealBytecodeOutput));
208 // Generate the bytecode file.
209 int StripLevel = Strip ? 2 : (StripDebug ? 1 : 0);
210 if (GenerateBytecode(Composite.get(), StripLevel, !NoInternalize, &Out)) {
212 return PrintAndReturn(argv[0], "error generating bytecode");
215 // Close the bytecode file.
218 // If we are not linking a library, generate either a native executable
219 // or a JIT shell script, depending upon what the user wants.
220 if (!LinkAsLibrary) {
221 // If the user wants to generate a native executable, compile it from the
224 // Otherwise, create a script that will run the bytecode through the JIT.
226 // Name of the Assembly Language output file
227 std::string AssemblyFile = OutputFilename + ".s";
229 // Mark the output files for removal if we get an interrupt.
230 sys::RemoveFileOnSignal(sys::Path(AssemblyFile));
231 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
233 // Determine the locations of the llc and gcc programs.
234 std::string llc = FindExecutable("llc", argv[0]);
235 std::string gcc = FindExecutable("gcc", argv[0]);
237 return PrintAndReturn(argv[0], "Failed to find llc");
240 return PrintAndReturn(argv[0], "Failed to find gcc");
242 // Generate an assembly language file for the bytecode.
243 if (Verbose) std::cout << "Generating Assembly Code\n";
244 GenerateAssembly(AssemblyFile, RealBytecodeOutput, llc, envp);
245 if (Verbose) std::cout << "Generating Native Code\n";
246 GenerateNative(OutputFilename, AssemblyFile, Libraries, LibPaths,
249 // Remove the assembly language file.
250 removeFile (AssemblyFile);
251 } else if (NativeCBE) {
252 std::string CFile = OutputFilename + ".cbe.c";
254 // Mark the output files for removal if we get an interrupt.
255 sys::RemoveFileOnSignal(sys::Path(CFile));
256 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
258 // Determine the locations of the llc and gcc programs.
259 std::string llc = FindExecutable("llc", argv[0]);
260 std::string gcc = FindExecutable("gcc", argv[0]);
262 return PrintAndReturn(argv[0], "Failed to find llc");
264 return PrintAndReturn(argv[0], "Failed to find gcc");
266 // Generate an assembly language file for the bytecode.
267 if (Verbose) std::cout << "Generating Assembly Code\n";
268 GenerateCFile(CFile, RealBytecodeOutput, llc, envp);
269 if (Verbose) std::cout << "Generating Native Code\n";
270 GenerateNative(OutputFilename, CFile, Libraries, LibPaths, gcc, envp);
272 // Remove the assembly language file.
276 EmitShellScript(argv);
279 // Make the script executable...
280 MakeFileExecutable(OutputFilename);
282 // Make the bytecode file readable and directly executable in LLEE as well
283 MakeFileExecutable(RealBytecodeOutput);
284 MakeFileReadable(RealBytecodeOutput);
286 } catch (const char*msg) {
287 std::cerr << argv[0] << ": " << msg << "\n";
289 } catch (const std::string& msg) {
290 std::cerr << argv[0] << ": " << msg << "\n";
293 // This really shouldn't happen, but just in case ....
294 std::cerr << argv[0] << ": An nexpected unknown exception occurred.\n";