1 //===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This is the llc code generator driver. It provides a convenient
11 // command-line interface for generating native assembly-language code
12 // or C code, given LLVM bitcode.
14 //===----------------------------------------------------------------------===//
16 #include "llvm/Bitcode/ReaderWriter.h"
17 #include "llvm/CodeGen/FileWriters.h"
18 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
19 #include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
20 #include "llvm/Target/SubtargetFeature.h"
21 #include "llvm/Target/TargetData.h"
22 #include "llvm/Target/TargetMachine.h"
23 #include "llvm/Target/TargetMachineRegistry.h"
24 #include "llvm/Transforms/Scalar.h"
25 #include "llvm/Module.h"
26 #include "llvm/ModuleProvider.h"
27 #include "llvm/PassManager.h"
28 #include "llvm/Pass.h"
29 #include "llvm/Support/CommandLine.h"
30 #include "llvm/Support/FileUtilities.h"
31 #include "llvm/Support/ManagedStatic.h"
32 #include "llvm/Support/MemoryBuffer.h"
33 #include "llvm/Support/PluginLoader.h"
34 #include "llvm/Support/PrettyStackTrace.h"
35 #include "llvm/Support/RegistryParser.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include "llvm/Analysis/Verifier.h"
38 #include "llvm/System/Signals.h"
39 #include "llvm/Config/config.h"
40 #include "llvm/LinkAllVMCore.h"
46 // General options for llc. Other pass-specific options are specified
47 // within the corresponding llc passes, and target-specific options
48 // and back-end code generation options are specified with the target machine.
50 static cl::opt<std::string>
51 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
53 static cl::opt<std::string>
54 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
56 static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
58 // Determine optimization level.
61 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
67 static cl::opt<std::string>
68 TargetTriple("mtriple", cl::desc("Override target triple for module"));
70 static cl::opt<const TargetMachineRegistry::entry*, false,
71 RegistryParser<TargetMachine> >
72 MArch("march", cl::desc("Architecture to generate code for:"));
74 static cl::opt<std::string>
76 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
77 cl::value_desc("cpu-name"),
80 static cl::list<std::string>
83 cl::desc("Target specific attributes (-mattr=help for details)"),
84 cl::value_desc("a1,+a2,-a3,..."));
86 cl::opt<TargetMachine::CodeGenFileType>
87 FileType("filetype", cl::init(TargetMachine::AssemblyFile),
88 cl::desc("Choose a file type (not all types are supported by all targets):"),
90 clEnumValN(TargetMachine::AssemblyFile, "asm",
91 "Emit an assembly ('.s') file"),
92 clEnumValN(TargetMachine::ObjectFile, "obj",
93 "Emit a native object ('.o') file [experimental]"),
94 clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
95 "Emit a native dynamic library ('.so') file"
99 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
100 cl::desc("Do not verify input module"));
104 DisableRedZone("disable-red-zone",
105 cl::desc("Do not emit code that uses the red zone."),
109 NoImplicitFloats("no-implicit-float",
110 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
113 // GetFileNameRoot - Helper function to get the basename of a filename.
114 static inline std::string
115 GetFileNameRoot(const std::string &InputFilename) {
116 std::string IFN = InputFilename;
117 std::string outputFilename;
118 int Len = IFN.length();
120 IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
121 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
123 outputFilename = IFN;
125 return outputFilename;
128 static raw_ostream *GetOutputStream(const char *ProgName) {
129 if (OutputFilename != "") {
130 if (OutputFilename == "-")
133 // Specified an output filename?
134 if (!Force && std::ifstream(OutputFilename.c_str())) {
135 // If force is not specified, make sure not to overwrite a file!
136 std::cerr << ProgName << ": error opening '" << OutputFilename
137 << "': file exists!\n"
138 << "Use -f command line argument to force output\n";
141 // Make sure that the Out file gets unlinked from the disk if we get a
143 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
146 raw_ostream *Out = new raw_fd_ostream(OutputFilename.c_str(), true, error);
147 if (!error.empty()) {
148 std::cerr << error << '\n';
156 if (InputFilename == "-") {
157 OutputFilename = "-";
161 OutputFilename = GetFileNameRoot(InputFilename);
165 case TargetMachine::AssemblyFile:
166 if (MArch->Name[0] == 'c') {
167 if (MArch->Name[1] == 0)
168 OutputFilename += ".cbe.c";
169 else if (MArch->Name[1] == 'p' && MArch->Name[2] == 'p')
170 OutputFilename += ".cpp";
172 OutputFilename += ".s";
174 OutputFilename += ".s";
176 case TargetMachine::ObjectFile:
177 OutputFilename += ".o";
180 case TargetMachine::DynamicLibrary:
181 OutputFilename += LTDL_SHLIB_EXT;
186 if (!Force && std::ifstream(OutputFilename.c_str())) {
187 // If force is not specified, make sure not to overwrite a file!
188 std::cerr << ProgName << ": error opening '" << OutputFilename
189 << "': file exists!\n"
190 << "Use -f command line argument to force output\n";
194 // Make sure that the Out file gets unlinked from the disk if we get a
196 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
199 raw_ostream *Out = new raw_fd_ostream(OutputFilename.c_str(), Binary, error);
200 if (!error.empty()) {
201 std::cerr << error << '\n';
209 // main - Entry point for the llc compiler.
211 int main(int argc, char **argv) {
212 sys::PrintStackTraceOnErrorSignal();
213 PrettyStackTraceProgram X(argc, argv);
214 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
215 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
217 // Load the module to be compiled...
218 std::string ErrorMessage;
219 std::auto_ptr<Module> M;
221 std::auto_ptr<MemoryBuffer> Buffer(
222 MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage));
224 M.reset(ParseBitcodeFile(Buffer.get(), &ErrorMessage));
226 std::cerr << argv[0] << ": bitcode didn't read correctly.\n";
227 std::cerr << "Reason: " << ErrorMessage << "\n";
230 Module &mod = *M.get();
232 // If we are supposed to override the target triple, do so now.
233 if (!TargetTriple.empty())
234 mod.setTargetTriple(TargetTriple);
236 // Allocate target machine. First, check whether the user has
237 // explicitly specified an architecture to compile for.
240 MArch = TargetMachineRegistry::getClosestStaticTargetForModule(mod, Err);
242 std::cerr << argv[0] << ": error auto-selecting target for module '"
243 << Err << "'. Please use the -march option to explicitly "
244 << "pick a target.\n";
249 // Package up features to be passed to target/subtarget
250 std::string FeaturesStr;
251 if (MCPU.size() || MAttrs.size()) {
252 SubtargetFeatures Features;
253 Features.setCPU(MCPU);
254 for (unsigned i = 0; i != MAttrs.size(); ++i)
255 Features.AddFeature(MAttrs[i]);
256 FeaturesStr = Features.getString();
259 std::auto_ptr<TargetMachine> target(MArch->CtorFn(mod, FeaturesStr));
260 assert(target.get() && "Could not allocate target machine!");
261 TargetMachine &Target = *target.get();
263 // Figure out where we are going to send the output...
264 raw_ostream *Out = GetOutputStream(argv[0]);
265 if (Out == 0) return 1;
267 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
270 std::cerr << argv[0] << ": invalid optimization level.\n";
273 case '0': OLvl = CodeGenOpt::None; break;
275 case '2': OLvl = CodeGenOpt::Default; break;
276 case '3': OLvl = CodeGenOpt::Aggressive; break;
279 // If this target requires addPassesToEmitWholeFile, do it now. This is
280 // used by strange things like the C backend.
281 if (Target.WantsWholeFile()) {
283 PM.add(new TargetData(*Target.getTargetData()));
285 PM.add(createVerifierPass());
287 // Ask the target to add backend passes as necessary.
288 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
289 std::cerr << argv[0] << ": target does not support generation of this"
291 if (Out != &outs()) delete Out;
292 // And the Out file is empty and useless, so remove it now.
293 sys::Path(OutputFilename).eraseFromDisk();
298 // Build up all of the passes that we want to do to the module.
299 ExistingModuleProvider Provider(M.release());
300 FunctionPassManager Passes(&Provider);
301 Passes.add(new TargetData(*Target.getTargetData()));
305 Passes.add(createVerifierPass());
308 // Ask the target to add backend passes as necessary.
309 MachineCodeEmitter *MCE = 0;
311 // Override default to generate verbose assembly.
312 Target.setAsmVerbosityDefault(true);
314 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
316 assert(0 && "Invalid file model!");
318 case FileModel::Error:
319 std::cerr << argv[0] << ": target does not support generation of this"
321 if (Out != &outs()) delete Out;
322 // And the Out file is empty and useless, so remove it now.
323 sys::Path(OutputFilename).eraseFromDisk();
325 case FileModel::AsmFile:
327 case FileModel::MachOFile:
328 MCE = AddMachOWriter(Passes, *Out, Target);
330 case FileModel::ElfFile:
331 MCE = AddELFWriter(Passes, *Out, Target);
335 if (Target.addPassesToEmitFileFinish(Passes, MCE, OLvl)) {
336 std::cerr << argv[0] << ": target does not support generation of this"
338 if (Out != &outs()) delete Out;
339 // And the Out file is empty and useless, so remove it now.
340 sys::Path(OutputFilename).eraseFromDisk();
344 Passes.doInitialization();
346 // Run our queue of passes all at once now, efficiently.
347 // TODO: this could lazily stream functions out of the module.
348 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
349 if (!I->isDeclaration()) {
351 I->addFnAttr(Attribute::NoRedZone);
352 if (NoImplicitFloats)
353 I->addFnAttr(Attribute::NoImplicitFloat);
357 Passes.doFinalization();
360 // Delete the ostream if it's not a stdout stream
361 if (Out != &outs()) delete Out;