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/LLVMContext.h"
17 #include "llvm/Module.h"
18 #include "llvm/PassManager.h"
19 #include "llvm/Pass.h"
20 #include "llvm/ADT/Triple.h"
21 #include "llvm/Analysis/Verifier.h"
22 #include "llvm/Support/IRReader.h"
23 #include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
24 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
25 #include "llvm/Config/config.h"
26 #include "llvm/LinkAllVMCore.h"
27 #include "llvm/Support/CommandLine.h"
28 #include "llvm/Support/Debug.h"
29 #include "llvm/Support/FileUtilities.h"
30 #include "llvm/Support/FormattedStream.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/System/Host.h"
36 #include "llvm/System/Signals.h"
37 #include "llvm/Target/SubtargetFeature.h"
38 #include "llvm/Target/TargetData.h"
39 #include "llvm/Target/TargetMachine.h"
40 #include "llvm/Target/TargetRegistry.h"
41 #include "llvm/Target/TargetSelect.h"
42 #include "llvm/Transforms/Scalar.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"));
57 Force("f", cl::desc("Enable binary output on terminals"));
59 // Determine optimization level.
62 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
68 static cl::opt<std::string>
69 TargetTriple("mtriple", cl::desc("Override target triple for module"));
71 static cl::opt<std::string>
72 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
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::CGFT_AssemblyFile),
88 cl::desc("Choose a file type (not all types are supported by all targets):"),
90 clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
91 "Emit an assembly ('.s') file"),
92 clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
93 "Emit a native object ('.o') file [experimental]"),
94 clEnumValN(TargetMachine::CGFT_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();
121 ((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
122 (IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
123 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
125 outputFilename = IFN;
127 return outputFilename;
130 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
131 const char *ProgName) {
132 if (OutputFilename != "") {
133 if (OutputFilename == "-")
136 // Make sure that the Out file gets unlinked from the disk if we get a
138 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
141 raw_fd_ostream *FDOut =
142 new raw_fd_ostream(OutputFilename.c_str(), error,
143 raw_fd_ostream::F_Binary);
144 if (!error.empty()) {
145 errs() << error << '\n';
149 formatted_raw_ostream *Out =
150 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
155 if (InputFilename == "-") {
156 OutputFilename = "-";
160 OutputFilename = GetFileNameRoot(InputFilename);
164 default: assert(0 && "Unknown file type");
165 case TargetMachine::CGFT_AssemblyFile:
166 if (TargetName[0] == 'c') {
167 if (TargetName[1] == 0)
168 OutputFilename += ".cbe.c";
169 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
170 OutputFilename += ".cpp";
172 OutputFilename += ".s";
174 OutputFilename += ".s";
176 case TargetMachine::CGFT_ObjectFile:
177 OutputFilename += ".o";
180 case TargetMachine::CGFT_DynamicLibrary:
181 OutputFilename += LTDL_SHLIB_EXT;
186 // Make sure that the Out file gets unlinked from the disk if we get a
188 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
191 unsigned OpenFlags = 0;
192 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
193 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(), error,
195 if (!error.empty()) {
196 errs() << error << '\n';
201 formatted_raw_ostream *Out =
202 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
207 // main - Entry point for the llc compiler.
209 int main(int argc, char **argv) {
210 sys::PrintStackTraceOnErrorSignal();
211 PrettyStackTraceProgram X(argc, argv);
213 // Enable debug stream buffering.
214 EnableDebugBuffering = true;
216 LLVMContext &Context = getGlobalContext();
217 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
219 // Initialize targets first, so that --version shows registered targets.
220 InitializeAllTargets();
221 InitializeAllAsmPrinters();
223 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
225 // Load the module to be compiled...
227 std::auto_ptr<Module> M;
229 M.reset(ParseIRFile(InputFilename, Err, Context));
231 Err.Print(argv[0], errs());
234 Module &mod = *M.get();
236 // If we are supposed to override the target triple, do so now.
237 if (!TargetTriple.empty())
238 mod.setTargetTriple(TargetTriple);
240 Triple TheTriple(mod.getTargetTriple());
241 if (TheTriple.getTriple().empty())
242 TheTriple.setTriple(sys::getHostTriple());
244 // Allocate target machine. First, check whether the user has explicitly
245 // specified an architecture to compile for. If so we have to look it up by
246 // name, because it might be a backend that has no mapping to a target triple.
247 const Target *TheTarget = 0;
248 if (!MArch.empty()) {
249 for (TargetRegistry::iterator it = TargetRegistry::begin(),
250 ie = TargetRegistry::end(); it != ie; ++it) {
251 if (MArch == it->getName()) {
258 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
262 // Adjust the triple to match (if known), otherwise stick with the
263 // module/host triple.
264 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
265 if (Type != Triple::UnknownArch)
266 TheTriple.setArch(Type);
269 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
270 if (TheTarget == 0) {
271 errs() << argv[0] << ": error auto-selecting target for module '"
272 << Err << "'. Please use the -march option to explicitly "
273 << "pick a target.\n";
278 // Package up features to be passed to target/subtarget
279 std::string FeaturesStr;
280 if (MCPU.size() || MAttrs.size()) {
281 SubtargetFeatures Features;
282 Features.setCPU(MCPU);
283 for (unsigned i = 0; i != MAttrs.size(); ++i)
284 Features.AddFeature(MAttrs[i]);
285 FeaturesStr = Features.getString();
288 std::auto_ptr<TargetMachine>
289 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
290 assert(target.get() && "Could not allocate target machine!");
291 TargetMachine &Target = *target.get();
293 // Figure out where we are going to send the output...
294 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
295 if (Out == 0) return 1;
297 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
300 errs() << argv[0] << ": invalid optimization level.\n";
303 case '0': OLvl = CodeGenOpt::None; break;
304 case '1': OLvl = CodeGenOpt::Less; break;
305 case '2': OLvl = CodeGenOpt::Default; break;
306 case '3': OLvl = CodeGenOpt::Aggressive; break;
309 // If this target requires addPassesToEmitWholeFile, do it now. This is
310 // used by strange things like the C backend.
311 if (Target.WantsWholeFile()) {
314 // Add the target data from the target machine, if it exists, or the module.
315 if (const TargetData *TD = Target.getTargetData())
316 PM.add(new TargetData(*TD));
318 PM.add(new TargetData(&mod));
321 PM.add(createVerifierPass());
323 // Ask the target to add backend passes as necessary.
324 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
325 errs() << argv[0] << ": target does not support generation of this"
327 if (Out != &fouts()) delete Out;
328 // And the Out file is empty and useless, so remove it now.
329 sys::Path(OutputFilename).eraseFromDisk();
334 // Build up all of the passes that we want to do to the module.
335 FunctionPassManager Passes(M.get());
337 // Add the target data from the target machine, if it exists, or the module.
338 if (const TargetData *TD = Target.getTargetData())
339 Passes.add(new TargetData(*TD));
341 Passes.add(new TargetData(&mod));
345 Passes.add(createVerifierPass());
348 // Override default to generate verbose assembly.
349 Target.setAsmVerbosityDefault(true);
351 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
353 assert(0 && "Invalid file model!");
355 case TargetMachine::CGFT_ErrorOccurred:
356 errs() << argv[0] << ": target does not support generation of this"
358 if (Out != &fouts()) delete Out;
359 // And the Out file is empty and useless, so remove it now.
360 sys::Path(OutputFilename).eraseFromDisk();
362 case TargetMachine::CGFT_AssemblyFile:
366 Passes.doInitialization();
368 // Run our queue of passes all at once now, efficiently.
369 // TODO: this could lazily stream functions out of the module.
370 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
371 if (!I->isDeclaration()) {
373 I->addFnAttr(Attribute::NoRedZone);
374 if (NoImplicitFloats)
375 I->addFnAttr(Attribute::NoImplicitFloat);
379 Passes.doFinalization();
382 // Delete the ostream if it's not a stdout stream
383 if (Out != &fouts()) delete Out;