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/FileUtilities.h"
29 #include "llvm/Support/FormattedStream.h"
30 #include "llvm/Support/ManagedStatic.h"
31 #include "llvm/Support/MemoryBuffer.h"
32 #include "llvm/Support/PluginLoader.h"
33 #include "llvm/Support/PrettyStackTrace.h"
34 #include "llvm/System/Host.h"
35 #include "llvm/System/Signals.h"
36 #include "llvm/Target/SubtargetFeature.h"
37 #include "llvm/Target/TargetData.h"
38 #include "llvm/Target/TargetMachine.h"
39 #include "llvm/Target/TargetRegistry.h"
40 #include "llvm/Target/TargetSelect.h"
41 #include "llvm/Transforms/Scalar.h"
45 // General options for llc. Other pass-specific options are specified
46 // within the corresponding llc passes, and target-specific options
47 // and back-end code generation options are specified with the target machine.
49 static cl::opt<std::string>
50 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
52 static cl::opt<std::string>
53 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
56 Force("f", cl::desc("Enable binary output on terminals"));
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<std::string>
71 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
73 static cl::opt<std::string>
75 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
76 cl::value_desc("cpu-name"),
79 static cl::list<std::string>
82 cl::desc("Target specific attributes (-mattr=help for details)"),
83 cl::value_desc("a1,+a2,-a3,..."));
85 cl::opt<TargetMachine::CodeGenFileType>
86 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
87 cl::desc("Choose a file type (not all types are supported by all targets):"),
89 clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
90 "Emit an assembly ('.s') file"),
91 clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
92 "Emit a native object ('.o') file [experimental]"),
93 clEnumValN(TargetMachine::CGFT_Null, "null",
94 "Emit nothing, for performance testing"),
97 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
98 cl::desc("Do not verify input module"));
102 DisableRedZone("disable-red-zone",
103 cl::desc("Do not emit code that uses the red zone."),
107 NoImplicitFloats("no-implicit-float",
108 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
111 // GetFileNameRoot - Helper function to get the basename of a filename.
112 static inline std::string
113 GetFileNameRoot(const std::string &InputFilename) {
114 std::string IFN = InputFilename;
115 std::string outputFilename;
116 int Len = IFN.length();
119 ((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
120 (IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
121 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
123 outputFilename = IFN;
125 return outputFilename;
128 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
129 const char *ProgName) {
130 if (OutputFilename != "") {
131 if (OutputFilename == "-")
134 // Make sure that the Out file gets unlinked from the disk if we get a
136 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
139 raw_fd_ostream *FDOut =
140 new raw_fd_ostream(OutputFilename.c_str(), error,
141 raw_fd_ostream::F_Binary);
142 if (!error.empty()) {
143 errs() << error << '\n';
147 formatted_raw_ostream *Out =
148 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
153 if (InputFilename == "-") {
154 OutputFilename = "-";
158 OutputFilename = GetFileNameRoot(InputFilename);
162 default: assert(0 && "Unknown file type");
163 case TargetMachine::CGFT_AssemblyFile:
164 if (TargetName[0] == 'c') {
165 if (TargetName[1] == 0)
166 OutputFilename += ".cbe.c";
167 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
168 OutputFilename += ".cpp";
170 OutputFilename += ".s";
172 OutputFilename += ".s";
174 case TargetMachine::CGFT_ObjectFile:
175 OutputFilename += ".o";
178 case TargetMachine::CGFT_Null:
179 OutputFilename += ".null";
184 // Make sure that the Out file gets unlinked from the disk if we get a
186 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
189 unsigned OpenFlags = 0;
190 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
191 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(), error,
193 if (!error.empty()) {
194 errs() << error << '\n';
199 formatted_raw_ostream *Out =
200 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
205 // main - Entry point for the llc compiler.
207 int main(int argc, char **argv) {
208 sys::PrintStackTraceOnErrorSignal();
209 PrettyStackTraceProgram X(argc, argv);
211 // Enable debug stream buffering.
212 EnableDebugBuffering = true;
214 LLVMContext &Context = getGlobalContext();
215 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
217 // Initialize targets first, so that --version shows registered targets.
218 InitializeAllTargets();
219 InitializeAllAsmPrinters();
221 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
223 // Load the module to be compiled...
225 std::auto_ptr<Module> M;
227 M.reset(ParseIRFile(InputFilename, Err, Context));
229 Err.Print(argv[0], errs());
232 Module &mod = *M.get();
234 // If we are supposed to override the target triple, do so now.
235 if (!TargetTriple.empty())
236 mod.setTargetTriple(TargetTriple);
238 Triple TheTriple(mod.getTargetTriple());
239 if (TheTriple.getTriple().empty())
240 TheTriple.setTriple(sys::getHostTriple());
242 // Allocate target machine. First, check whether the user has explicitly
243 // specified an architecture to compile for. If so we have to look it up by
244 // name, because it might be a backend that has no mapping to a target triple.
245 const Target *TheTarget = 0;
246 if (!MArch.empty()) {
247 for (TargetRegistry::iterator it = TargetRegistry::begin(),
248 ie = TargetRegistry::end(); it != ie; ++it) {
249 if (MArch == it->getName()) {
256 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
260 // Adjust the triple to match (if known), otherwise stick with the
261 // module/host triple.
262 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
263 if (Type != Triple::UnknownArch)
264 TheTriple.setArch(Type);
267 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
268 if (TheTarget == 0) {
269 errs() << argv[0] << ": error auto-selecting target for module '"
270 << Err << "'. Please use the -march option to explicitly "
271 << "pick a target.\n";
276 // Package up features to be passed to target/subtarget
277 std::string FeaturesStr;
278 if (MCPU.size() || MAttrs.size()) {
279 SubtargetFeatures Features;
280 Features.setCPU(MCPU);
281 for (unsigned i = 0; i != MAttrs.size(); ++i)
282 Features.AddFeature(MAttrs[i]);
283 FeaturesStr = Features.getString();
286 std::auto_ptr<TargetMachine>
287 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
288 assert(target.get() && "Could not allocate target machine!");
289 TargetMachine &Target = *target.get();
291 // Figure out where we are going to send the output...
292 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
293 if (Out == 0) return 1;
295 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
298 errs() << argv[0] << ": invalid optimization level.\n";
301 case '0': OLvl = CodeGenOpt::None; break;
302 case '1': OLvl = CodeGenOpt::Less; break;
303 case '2': OLvl = CodeGenOpt::Default; break;
304 case '3': OLvl = CodeGenOpt::Aggressive; break;
307 // Request that addPassesToEmitFile run the Verifier after running
308 // passes which modify the IR.
310 bool DisableVerify = false;
312 bool DisableVerify = true;
315 // If this target requires addPassesToEmitWholeFile, do it now. This is
316 // used by strange things like the C backend.
317 if (Target.WantsWholeFile()) {
320 // Add the target data from the target machine, if it exists, or the module.
321 if (const TargetData *TD = Target.getTargetData())
322 PM.add(new TargetData(*TD));
324 PM.add(new TargetData(&mod));
327 PM.add(createVerifierPass());
329 // Ask the target to add backend passes as necessary.
330 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl,
332 errs() << 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();
341 // Build up all of the passes that we want to do to the module.
342 FunctionPassManager Passes(M.get());
344 // Add the target data from the target machine, if it exists, or the module.
345 if (const TargetData *TD = Target.getTargetData())
346 Passes.add(new TargetData(*TD));
348 Passes.add(new TargetData(&mod));
352 Passes.add(createVerifierPass());
355 // Override default to generate verbose assembly.
356 Target.setAsmVerbosityDefault(true);
358 if (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl,
360 errs() << argv[0] << ": target does not support generation of this"
362 if (Out != &fouts()) delete Out;
363 // And the Out file is empty and useless, so remove it now.
364 sys::Path(OutputFilename).eraseFromDisk();
368 Passes.doInitialization();
370 // Run our queue of passes all at once now, efficiently.
371 // TODO: this could lazily stream functions out of the module.
372 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
373 if (!I->isDeclaration()) {
375 I->addFnAttr(Attribute::NoRedZone);
376 if (NoImplicitFloats)
377 I->addFnAttr(Attribute::NoImplicitFloat);
381 Passes.doFinalization();
384 // Delete the ostream if it's not a stdout stream
385 if (Out != &fouts()) delete Out;