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/Support/CommandLine.h"
27 #include "llvm/Support/Debug.h"
28 #include "llvm/Support/FormattedStream.h"
29 #include "llvm/Support/ManagedStatic.h"
30 #include "llvm/Support/PluginLoader.h"
31 #include "llvm/Support/PrettyStackTrace.h"
32 #include "llvm/System/Host.h"
33 #include "llvm/System/Signals.h"
34 #include "llvm/Target/SubtargetFeature.h"
35 #include "llvm/Target/TargetData.h"
36 #include "llvm/Target/TargetMachine.h"
37 #include "llvm/Target/TargetRegistry.h"
38 #include "llvm/Target/TargetSelect.h"
42 // General options for llc. Other pass-specific options are specified
43 // within the corresponding llc passes, and target-specific options
44 // and back-end code generation options are specified with the target machine.
46 static cl::opt<std::string>
47 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
49 static cl::opt<std::string>
50 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
52 // Determine optimization level.
55 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
61 static cl::opt<std::string>
62 TargetTriple("mtriple", cl::desc("Override target triple for module"));
64 static cl::opt<std::string>
65 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
67 static cl::opt<std::string>
69 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
70 cl::value_desc("cpu-name"),
73 static cl::list<std::string>
76 cl::desc("Target specific attributes (-mattr=help for details)"),
77 cl::value_desc("a1,+a2,-a3,..."));
80 RelaxAll("mc-relax-all",
81 cl::desc("When used with filetype=obj, "
82 "relax all fixups in the emitted object file"));
84 cl::opt<TargetMachine::CodeGenFileType>
85 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
86 cl::desc("Choose a file type (not all types are supported by all targets):"),
88 clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
89 "Emit an assembly ('.s') file"),
90 clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
91 "Emit a native object ('.o') file [experimental]"),
92 clEnumValN(TargetMachine::CGFT_Null, "null",
93 "Emit nothing, for performance testing"),
96 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
97 cl::desc("Do not verify input module"));
101 DisableRedZone("disable-red-zone",
102 cl::desc("Do not emit code that uses the red zone."),
106 NoImplicitFloats("no-implicit-float",
107 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
110 // GetFileNameRoot - Helper function to get the basename of a filename.
111 static inline std::string
112 GetFileNameRoot(const std::string &InputFilename) {
113 std::string IFN = InputFilename;
114 std::string outputFilename;
115 int Len = IFN.length();
118 ((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
119 (IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
120 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
122 outputFilename = IFN;
124 return outputFilename;
127 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
129 const char *ProgName) {
130 if (!OutputFilename.empty()) {
131 // Make sure that the Out file gets unlinked from the disk if we get a
133 if (OutputFilename != "-")
134 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
137 raw_fd_ostream *FDOut =
138 new raw_fd_ostream(OutputFilename.c_str(), error,
139 raw_fd_ostream::F_Binary);
140 if (!error.empty()) {
141 errs() << error << '\n';
145 formatted_raw_ostream *Out =
146 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
151 if (InputFilename == "-") {
152 OutputFilename = "-";
153 return new formatted_raw_ostream(outs(),
154 formatted_raw_ostream::PRESERVE_STREAM);
157 OutputFilename = GetFileNameRoot(InputFilename);
161 default: assert(0 && "Unknown file type");
162 case TargetMachine::CGFT_AssemblyFile:
163 if (TargetName[0] == 'c') {
164 if (TargetName[1] == 0)
165 OutputFilename += ".cbe.c";
166 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
167 OutputFilename += ".cpp";
169 OutputFilename += ".s";
171 OutputFilename += ".s";
173 case TargetMachine::CGFT_ObjectFile:
174 if (OS == Triple::Win32)
175 OutputFilename += ".obj";
177 OutputFilename += ".o";
180 case TargetMachine::CGFT_Null:
181 OutputFilename += ".null";
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();
222 InitializeAllAsmParsers();
224 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
226 // Load the module to be compiled...
228 std::auto_ptr<Module> M;
230 M.reset(ParseIRFile(InputFilename, Err, Context));
232 Err.Print(argv[0], errs());
235 Module &mod = *M.get();
237 // If we are supposed to override the target triple, do so now.
238 if (!TargetTriple.empty())
239 mod.setTargetTriple(TargetTriple);
241 Triple TheTriple(mod.getTargetTriple());
242 if (TheTriple.getTriple().empty())
243 TheTriple.setTriple(sys::getHostTriple());
245 // Allocate target machine. First, check whether the user has explicitly
246 // specified an architecture to compile for. If so we have to look it up by
247 // name, because it might be a backend that has no mapping to a target triple.
248 const Target *TheTarget = 0;
249 if (!MArch.empty()) {
250 for (TargetRegistry::iterator it = TargetRegistry::begin(),
251 ie = TargetRegistry::end(); it != ie; ++it) {
252 if (MArch == it->getName()) {
259 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
263 // Adjust the triple to match (if known), otherwise stick with the
264 // module/host triple.
265 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
266 if (Type != Triple::UnknownArch)
267 TheTriple.setArch(Type);
270 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
271 if (TheTarget == 0) {
272 errs() << argv[0] << ": error auto-selecting target for module '"
273 << Err << "'. Please use the -march option to explicitly "
274 << "pick a target.\n";
279 // Package up features to be passed to target/subtarget
280 std::string FeaturesStr;
281 if (MCPU.size() || MAttrs.size()) {
282 SubtargetFeatures Features;
283 Features.setCPU(MCPU);
284 for (unsigned i = 0; i != MAttrs.size(); ++i)
285 Features.AddFeature(MAttrs[i]);
286 FeaturesStr = Features.getString();
289 std::auto_ptr<TargetMachine>
290 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
291 assert(target.get() && "Could not allocate target machine!");
292 TargetMachine &Target = *target.get();
294 // Figure out where we are going to send the output...
295 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(),
296 TheTriple.getOS(), argv[0]);
297 if (Out == 0) return 1;
299 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
302 errs() << argv[0] << ": invalid optimization level.\n";
305 case '0': OLvl = CodeGenOpt::None; break;
306 case '1': OLvl = CodeGenOpt::Less; break;
307 case '2': OLvl = CodeGenOpt::Default; break;
308 case '3': OLvl = CodeGenOpt::Aggressive; break;
311 // Request that addPassesToEmitFile run the Verifier after running
312 // passes which modify the IR.
314 bool DisableVerify = false;
316 bool DisableVerify = true;
319 // Build up all of the passes that we want to do to the module.
322 // Add the target data from the target machine, if it exists, or the module.
323 if (const TargetData *TD = Target.getTargetData())
324 PM.add(new TargetData(*TD));
326 PM.add(new TargetData(&mod));
329 PM.add(createVerifierPass());
331 // Override default to generate verbose assembly.
332 Target.setAsmVerbosityDefault(true);
335 if (FileType != TargetMachine::CGFT_ObjectFile)
337 << ": warning: ignoring -mc-relax-all because filetype != obj";
339 Target.setMCRelaxAll(true);
342 // Ask the target to add backend passes as necessary.
343 if (Target.addPassesToEmitFile(PM, *Out, FileType, OLvl,
345 errs() << argv[0] << ": target does not support generation of this"
348 // And the Out file is empty and useless, so remove it now.
349 sys::Path(OutputFilename).eraseFromDisk();
355 // Delete the ostream.