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 != "") {
131 if (OutputFilename == "-")
132 return new formatted_raw_ostream(outs(),
133 formatted_raw_ostream::PRESERVE_STREAM);
135 // Make sure that the Out file gets unlinked from the disk if we get a
137 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
140 raw_fd_ostream *FDOut =
141 new raw_fd_ostream(OutputFilename.c_str(), error,
142 raw_fd_ostream::F_Binary);
143 if (!error.empty()) {
144 errs() << error << '\n';
148 formatted_raw_ostream *Out =
149 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
154 if (InputFilename == "-") {
155 OutputFilename = "-";
156 return new formatted_raw_ostream(outs(),
157 formatted_raw_ostream::PRESERVE_STREAM);
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 if (OS == Triple::Win32)
178 OutputFilename += ".obj";
180 OutputFilename += ".o";
183 case TargetMachine::CGFT_Null:
184 OutputFilename += ".null";
189 // Make sure that the Out file gets unlinked from the disk if we get a
191 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
194 unsigned OpenFlags = 0;
195 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
196 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(), error,
198 if (!error.empty()) {
199 errs() << error << '\n';
204 formatted_raw_ostream *Out =
205 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
210 // main - Entry point for the llc compiler.
212 int main(int argc, char **argv) {
213 sys::PrintStackTraceOnErrorSignal();
214 PrettyStackTraceProgram X(argc, argv);
216 // Enable debug stream buffering.
217 EnableDebugBuffering = true;
219 LLVMContext &Context = getGlobalContext();
220 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
222 // Initialize targets first, so that --version shows registered targets.
223 InitializeAllTargets();
224 InitializeAllAsmPrinters();
225 InitializeAllAsmParsers();
227 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
229 // Load the module to be compiled...
231 std::auto_ptr<Module> M;
233 M.reset(ParseIRFile(InputFilename, Err, Context));
235 Err.Print(argv[0], errs());
238 Module &mod = *M.get();
240 // If we are supposed to override the target triple, do so now.
241 if (!TargetTriple.empty())
242 mod.setTargetTriple(TargetTriple);
244 Triple TheTriple(mod.getTargetTriple());
245 if (TheTriple.getTriple().empty())
246 TheTriple.setTriple(sys::getHostTriple());
248 // Allocate target machine. First, check whether the user has explicitly
249 // specified an architecture to compile for. If so we have to look it up by
250 // name, because it might be a backend that has no mapping to a target triple.
251 const Target *TheTarget = 0;
252 if (!MArch.empty()) {
253 for (TargetRegistry::iterator it = TargetRegistry::begin(),
254 ie = TargetRegistry::end(); it != ie; ++it) {
255 if (MArch == it->getName()) {
262 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
266 // Adjust the triple to match (if known), otherwise stick with the
267 // module/host triple.
268 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
269 if (Type != Triple::UnknownArch)
270 TheTriple.setArch(Type);
273 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
274 if (TheTarget == 0) {
275 errs() << argv[0] << ": error auto-selecting target for module '"
276 << Err << "'. Please use the -march option to explicitly "
277 << "pick a target.\n";
282 // Package up features to be passed to target/subtarget
283 std::string FeaturesStr;
284 if (MCPU.size() || MAttrs.size()) {
285 SubtargetFeatures Features;
286 Features.setCPU(MCPU);
287 for (unsigned i = 0; i != MAttrs.size(); ++i)
288 Features.AddFeature(MAttrs[i]);
289 FeaturesStr = Features.getString();
292 std::auto_ptr<TargetMachine>
293 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
294 assert(target.get() && "Could not allocate target machine!");
295 TargetMachine &Target = *target.get();
297 // Figure out where we are going to send the output...
298 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(),
299 TheTriple.getOS(), argv[0]);
300 if (Out == 0) return 1;
302 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
305 errs() << argv[0] << ": invalid optimization level.\n";
308 case '0': OLvl = CodeGenOpt::None; break;
309 case '1': OLvl = CodeGenOpt::Less; break;
310 case '2': OLvl = CodeGenOpt::Default; break;
311 case '3': OLvl = CodeGenOpt::Aggressive; break;
314 // Request that addPassesToEmitFile run the Verifier after running
315 // passes which modify the IR.
317 bool DisableVerify = false;
319 bool DisableVerify = true;
322 // Build up all of the passes that we want to do to the module.
325 // Add the target data from the target machine, if it exists, or the module.
326 if (const TargetData *TD = Target.getTargetData())
327 PM.add(new TargetData(*TD));
329 PM.add(new TargetData(&mod));
332 PM.add(createVerifierPass());
334 // Override default to generate verbose assembly.
335 Target.setAsmVerbosityDefault(true);
338 if (FileType != TargetMachine::CGFT_ObjectFile)
340 << ": warning: ignoring -mc-relax-all because filetype != obj";
342 Target.setMCRelaxAll(true);
345 // Ask the target to add backend passes as necessary.
346 if (Target.addPassesToEmitFile(PM, *Out, FileType, OLvl,
348 errs() << argv[0] << ": target does not support generation of this"
351 // And the Out file is empty and useless, so remove it now.
352 sys::Path(OutputFilename).eraseFromDisk();
358 // Delete the ostream.