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/CodeGen/ObjectCodeEmitter.h"
21 #include "llvm/Target/SubtargetFeature.h"
22 #include "llvm/Target/TargetData.h"
23 #include "llvm/Target/TargetMachine.h"
24 #include "llvm/Target/TargetMachineRegistry.h"
25 #include "llvm/Transforms/Scalar.h"
26 #include "llvm/LLVMContext.h"
27 #include "llvm/Module.h"
28 #include "llvm/ModuleProvider.h"
29 #include "llvm/PassManager.h"
30 #include "llvm/Pass.h"
31 #include "llvm/Support/CommandLine.h"
32 #include "llvm/Support/FileUtilities.h"
33 #include "llvm/Support/FormattedStream.h"
34 #include "llvm/Support/ManagedStatic.h"
35 #include "llvm/Support/MemoryBuffer.h"
36 #include "llvm/Support/PluginLoader.h"
37 #include "llvm/Support/PrettyStackTrace.h"
38 #include "llvm/Support/RegistryParser.h"
39 #include "llvm/Analysis/Verifier.h"
40 #include "llvm/System/Signals.h"
41 #include "llvm/Config/config.h"
42 #include "llvm/LinkAllVMCore.h"
43 #include "llvm/Target/TargetSelect.h"
49 // General options for llc. Other pass-specific options are specified
50 // within the corresponding llc passes, and target-specific options
51 // and back-end code generation options are specified with the target machine.
53 static cl::opt<std::string>
54 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
56 static cl::opt<std::string>
57 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
59 static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
61 // Determine optimization level.
64 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
70 static cl::opt<std::string>
71 TargetTriple("mtriple", cl::desc("Override target triple for module"));
73 static cl::opt<const TargetMachineRegistry::entry*, false,
74 RegistryParser<TargetMachine> >
75 MArch("march", cl::desc("Architecture to generate code for:"));
77 static cl::opt<std::string>
79 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
80 cl::value_desc("cpu-name"),
83 static cl::list<std::string>
86 cl::desc("Target specific attributes (-mattr=help for details)"),
87 cl::value_desc("a1,+a2,-a3,..."));
89 cl::opt<TargetMachine::CodeGenFileType>
90 FileType("filetype", cl::init(TargetMachine::AssemblyFile),
91 cl::desc("Choose a file type (not all types are supported by all targets):"),
93 clEnumValN(TargetMachine::AssemblyFile, "asm",
94 "Emit an assembly ('.s') file"),
95 clEnumValN(TargetMachine::ObjectFile, "obj",
96 "Emit a native object ('.o') file [experimental]"),
97 clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
98 "Emit a native dynamic library ('.so') file"
102 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
103 cl::desc("Do not verify input module"));
107 DisableRedZone("disable-red-zone",
108 cl::desc("Do not emit code that uses the red zone."),
112 NoImplicitFloats("no-implicit-float",
113 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
116 // GetFileNameRoot - Helper function to get the basename of a filename.
117 static inline std::string
118 GetFileNameRoot(const std::string &InputFilename) {
119 std::string IFN = InputFilename;
120 std::string outputFilename;
121 int Len = IFN.length();
123 IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
124 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
126 outputFilename = IFN;
128 return outputFilename;
131 static formatted_raw_ostream *GetOutputStream(const char *ProgName) {
132 if (OutputFilename != "") {
133 if (OutputFilename == "-")
136 // Specified an output filename?
137 if (!Force && std::ifstream(OutputFilename.c_str())) {
138 // If force is not specified, make sure not to overwrite a file!
139 std::cerr << ProgName << ": error opening '" << OutputFilename
140 << "': file exists!\n"
141 << "Use -f command line argument to force output\n";
144 // Make sure that the Out file gets unlinked from the disk if we get a
146 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
149 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(),
151 formatted_raw_ostream *Out =
152 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
153 if (!error.empty()) {
154 std::cerr << error << '\n';
162 if (InputFilename == "-") {
163 OutputFilename = "-";
167 OutputFilename = GetFileNameRoot(InputFilename);
171 case TargetMachine::AssemblyFile:
172 if (MArch->Name[0] == 'c') {
173 if (MArch->Name[1] == 0)
174 OutputFilename += ".cbe.c";
175 else if (MArch->Name[1] == 'p' && MArch->Name[2] == 'p')
176 OutputFilename += ".cpp";
178 OutputFilename += ".s";
180 OutputFilename += ".s";
182 case TargetMachine::ObjectFile:
183 OutputFilename += ".o";
186 case TargetMachine::DynamicLibrary:
187 OutputFilename += LTDL_SHLIB_EXT;
192 if (!Force && std::ifstream(OutputFilename.c_str())) {
193 // If force is not specified, make sure not to overwrite a file!
194 std::cerr << ProgName << ": error opening '" << OutputFilename
195 << "': file exists!\n"
196 << "Use -f command line argument to force output\n";
200 // Make sure that the Out file gets unlinked from the disk if we get a
202 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
205 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(),
207 formatted_raw_ostream *Out =
208 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
209 if (!error.empty()) {
210 std::cerr << error << '\n';
218 // main - Entry point for the llc compiler.
220 int main(int argc, char **argv) {
221 sys::PrintStackTraceOnErrorSignal();
222 PrettyStackTraceProgram X(argc, argv);
224 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
225 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
227 InitializeAllTargets();
228 InitializeAllAsmPrinters();
230 // Load the module to be compiled...
231 std::string ErrorMessage;
232 std::auto_ptr<Module> M;
234 std::auto_ptr<MemoryBuffer> Buffer(
235 MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage));
237 M.reset(ParseBitcodeFile(Buffer.get(), Context, &ErrorMessage));
239 std::cerr << argv[0] << ": bitcode didn't read correctly.\n";
240 std::cerr << "Reason: " << ErrorMessage << "\n";
243 Module &mod = *M.get();
245 // If we are supposed to override the target triple, do so now.
246 if (!TargetTriple.empty())
247 mod.setTargetTriple(TargetTriple);
249 // Allocate target machine. First, check whether the user has
250 // explicitly specified an architecture to compile for.
253 MArch = TargetMachineRegistry::getClosestStaticTargetForModule(mod, Err);
255 std::cerr << argv[0] << ": error auto-selecting target for module '"
256 << Err << "'. Please use the -march option to explicitly "
257 << "pick a target.\n";
262 // Package up features to be passed to target/subtarget
263 std::string FeaturesStr;
264 if (MCPU.size() || MAttrs.size()) {
265 SubtargetFeatures Features;
266 Features.setCPU(MCPU);
267 for (unsigned i = 0; i != MAttrs.size(); ++i)
268 Features.AddFeature(MAttrs[i]);
269 FeaturesStr = Features.getString();
272 std::auto_ptr<TargetMachine> target(MArch->CtorFn(mod, FeaturesStr));
273 assert(target.get() && "Could not allocate target machine!");
274 TargetMachine &Target = *target.get();
276 // Figure out where we are going to send the output...
277 formatted_raw_ostream *Out = GetOutputStream(argv[0]);
278 if (Out == 0) return 1;
280 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
283 std::cerr << argv[0] << ": invalid optimization level.\n";
286 case '0': OLvl = CodeGenOpt::None; break;
288 case '2': OLvl = CodeGenOpt::Default; break;
289 case '3': OLvl = CodeGenOpt::Aggressive; break;
292 // If this target requires addPassesToEmitWholeFile, do it now. This is
293 // used by strange things like the C backend.
294 if (Target.WantsWholeFile()) {
296 PM.add(new TargetData(*Target.getTargetData()));
298 PM.add(createVerifierPass());
300 // Ask the target to add backend passes as necessary.
301 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
302 std::cerr << argv[0] << ": target does not support generation of this"
304 if (Out != &fouts()) delete Out;
305 // And the Out file is empty and useless, so remove it now.
306 sys::Path(OutputFilename).eraseFromDisk();
311 // Build up all of the passes that we want to do to the module.
312 ExistingModuleProvider Provider(M.release());
313 FunctionPassManager Passes(&Provider);
314 Passes.add(new TargetData(*Target.getTargetData()));
318 Passes.add(createVerifierPass());
321 // Ask the target to add backend passes as necessary.
322 ObjectCodeEmitter *OCE = 0;
324 // Override default to generate verbose assembly.
325 Target.setAsmVerbosityDefault(true);
327 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
329 assert(0 && "Invalid file model!");
331 case FileModel::Error:
332 std::cerr << argv[0] << ": target does not support generation of this"
334 if (Out != &fouts()) delete Out;
335 // And the Out file is empty and useless, so remove it now.
336 sys::Path(OutputFilename).eraseFromDisk();
338 case FileModel::AsmFile:
340 case FileModel::MachOFile:
341 OCE = AddMachOWriter(Passes, *Out, Target);
343 case FileModel::ElfFile:
344 OCE = AddELFWriter(Passes, *Out, Target);
348 if (Target.addPassesToEmitFileFinish(Passes, OCE, OLvl)) {
349 std::cerr << argv[0] << ": target does not support generation of this"
351 if (Out != &fouts()) delete Out;
352 // And the Out file is empty and useless, so remove it now.
353 sys::Path(OutputFilename).eraseFromDisk();
357 Passes.doInitialization();
359 // Run our queue of passes all at once now, efficiently.
360 // TODO: this could lazily stream functions out of the module.
361 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
362 if (!I->isDeclaration()) {
364 I->addFnAttr(Attribute::NoRedZone);
365 if (NoImplicitFloats)
366 I->addFnAttr(Attribute::NoImplicitFloat);
370 Passes.doFinalization();
375 // Delete the ostream if it's not a stdout stream
376 if (Out != &fouts()) delete Out;