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/ModuleProvider.h"
19 #include "llvm/PassManager.h"
20 #include "llvm/Pass.h"
21 #include "llvm/ADT/Triple.h"
22 #include "llvm/Analysis/Verifier.h"
23 #include "llvm/Support/IRReader.h"
24 #include "llvm/CodeGen/FileWriters.h"
25 #include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
26 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
27 #include "llvm/CodeGen/ObjectCodeEmitter.h"
28 #include "llvm/Config/config.h"
29 #include "llvm/LinkAllVMCore.h"
30 #include "llvm/Support/CommandLine.h"
31 #include "llvm/Support/FileUtilities.h"
32 #include "llvm/Support/FormattedStream.h"
33 #include "llvm/Support/ManagedStatic.h"
34 #include "llvm/Support/MemoryBuffer.h"
35 #include "llvm/Support/PluginLoader.h"
36 #include "llvm/Support/PrettyStackTrace.h"
37 #include "llvm/System/Host.h"
38 #include "llvm/System/Signals.h"
39 #include "llvm/Target/SubtargetFeature.h"
40 #include "llvm/Target/TargetData.h"
41 #include "llvm/Target/TargetMachine.h"
42 #include "llvm/Target/TargetRegistry.h"
43 #include "llvm/Target/TargetSelect.h"
44 #include "llvm/Transforms/Scalar.h"
48 // General options for llc. Other pass-specific options are specified
49 // within the corresponding llc passes, and target-specific options
50 // and back-end code generation options are specified with the target machine.
52 static cl::opt<std::string>
53 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
55 static cl::opt<std::string>
56 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
59 Force("f", cl::desc("Enable binary output on terminals"));
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<std::string>
74 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
76 static cl::opt<std::string>
78 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
79 cl::value_desc("cpu-name"),
82 static cl::list<std::string>
85 cl::desc("Target specific attributes (-mattr=help for details)"),
86 cl::value_desc("a1,+a2,-a3,..."));
88 cl::opt<TargetMachine::CodeGenFileType>
89 FileType("filetype", cl::init(TargetMachine::AssemblyFile),
90 cl::desc("Choose a file type (not all types are supported by all targets):"),
92 clEnumValN(TargetMachine::AssemblyFile, "asm",
93 "Emit an assembly ('.s') file"),
94 clEnumValN(TargetMachine::ObjectFile, "obj",
95 "Emit a native object ('.o') file [experimental]"),
96 clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
97 "Emit a native dynamic library ('.so') file"
101 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
102 cl::desc("Do not verify input module"));
106 DisableRedZone("disable-red-zone",
107 cl::desc("Do not emit code that uses the red zone."),
111 NoImplicitFloats("no-implicit-float",
112 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
115 // GetFileNameRoot - Helper function to get the basename of a filename.
116 static inline std::string
117 GetFileNameRoot(const std::string &InputFilename) {
118 std::string IFN = InputFilename;
119 std::string outputFilename;
120 int Len = IFN.length();
123 ((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
124 (IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
125 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
127 outputFilename = IFN;
129 return outputFilename;
132 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
133 const char *ProgName) {
134 if (OutputFilename != "") {
135 if (OutputFilename == "-")
138 // Make sure that the Out file gets unlinked from the disk if we get a
140 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
143 raw_fd_ostream *FDOut =
144 new raw_fd_ostream(OutputFilename.c_str(), error,
145 raw_fd_ostream::F_Binary);
146 if (!error.empty()) {
147 errs() << error << '\n';
151 formatted_raw_ostream *Out =
152 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
157 if (InputFilename == "-") {
158 OutputFilename = "-";
162 OutputFilename = GetFileNameRoot(InputFilename);
166 case TargetMachine::AssemblyFile:
167 if (TargetName[0] == 'c') {
168 if (TargetName[1] == 0)
169 OutputFilename += ".cbe.c";
170 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
171 OutputFilename += ".cpp";
173 OutputFilename += ".s";
175 OutputFilename += ".s";
177 case TargetMachine::ObjectFile:
178 OutputFilename += ".o";
181 case TargetMachine::DynamicLibrary:
182 OutputFilename += LTDL_SHLIB_EXT;
187 // Make sure that the Out file gets unlinked from the disk if we get a
189 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
192 unsigned OpenFlags = 0;
193 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
194 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(), error,
196 if (!error.empty()) {
197 errs() << error << '\n';
202 formatted_raw_ostream *Out =
203 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
208 // main - Entry point for the llc compiler.
210 int main(int argc, char **argv) {
211 sys::PrintStackTraceOnErrorSignal();
212 PrettyStackTraceProgram X(argc, argv);
213 LLVMContext &Context = getGlobalContext();
214 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
216 // Initialize targets first, so that --version shows registered targets.
217 InitializeAllTargets();
218 InitializeAllAsmPrinters();
220 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
222 // Load the module to be compiled...
224 std::auto_ptr<Module> M;
226 M.reset(ParseIRFile(InputFilename, Err, Context));
228 Err.Print(argv[0], errs());
231 Module &mod = *M.get();
233 // If we are supposed to override the target triple, do so now.
234 if (!TargetTriple.empty())
235 mod.setTargetTriple(TargetTriple);
237 Triple TheTriple(mod.getTargetTriple());
238 if (TheTriple.getTriple().empty())
239 TheTriple.setTriple(sys::getHostTriple());
241 // Allocate target machine. First, check whether the user has explicitly
242 // specified an architecture to compile for. If so we have to look it up by
243 // name, because it might be a backend that has no mapping to a target triple.
244 const Target *TheTarget = 0;
245 if (!MArch.empty()) {
246 for (TargetRegistry::iterator it = TargetRegistry::begin(),
247 ie = TargetRegistry::end(); it != ie; ++it) {
248 if (MArch == it->getName()) {
255 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
259 // Adjust the triple to match (if known), otherwise stick with the
260 // module/host triple.
261 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
262 if (Type != Triple::UnknownArch)
263 TheTriple.setArch(Type);
266 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
267 if (TheTarget == 0) {
268 errs() << argv[0] << ": error auto-selecting target for module '"
269 << Err << "'. Please use the -march option to explicitly "
270 << "pick a target.\n";
275 // Package up features to be passed to target/subtarget
276 std::string FeaturesStr;
277 if (MCPU.size() || MAttrs.size()) {
278 SubtargetFeatures Features;
279 Features.setCPU(MCPU);
280 for (unsigned i = 0; i != MAttrs.size(); ++i)
281 Features.AddFeature(MAttrs[i]);
282 FeaturesStr = Features.getString();
285 std::auto_ptr<TargetMachine>
286 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
287 assert(target.get() && "Could not allocate target machine!");
288 TargetMachine &Target = *target.get();
290 // Figure out where we are going to send the output...
291 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
292 if (Out == 0) return 1;
294 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
297 errs() << argv[0] << ": invalid optimization level.\n";
300 case '0': OLvl = CodeGenOpt::None; break;
302 case '2': OLvl = CodeGenOpt::Default; break;
303 case '3': OLvl = CodeGenOpt::Aggressive; break;
306 // If this target requires addPassesToEmitWholeFile, do it now. This is
307 // used by strange things like the C backend.
308 if (Target.WantsWholeFile()) {
311 // Add the target data from the target machine, if it exists, or the module.
312 if (const TargetData *TD = Target.getTargetData())
313 PM.add(new TargetData(*TD));
315 PM.add(new TargetData(&mod));
318 PM.add(createVerifierPass());
320 // Ask the target to add backend passes as necessary.
321 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
322 errs() << argv[0] << ": target does not support generation of this"
324 if (Out != &fouts()) delete Out;
325 // And the Out file is empty and useless, so remove it now.
326 sys::Path(OutputFilename).eraseFromDisk();
331 // Build up all of the passes that we want to do to the module.
332 ExistingModuleProvider Provider(M.release());
333 FunctionPassManager Passes(&Provider);
335 // Add the target data from the target machine, if it exists, or the module.
336 if (const TargetData *TD = Target.getTargetData())
337 Passes.add(new TargetData(*TD));
339 Passes.add(new TargetData(&mod));
343 Passes.add(createVerifierPass());
346 // Ask the target to add backend passes as necessary.
347 ObjectCodeEmitter *OCE = 0;
349 // Override default to generate verbose assembly.
350 Target.setAsmVerbosityDefault(true);
352 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
354 assert(0 && "Invalid file model!");
356 case FileModel::Error:
357 errs() << argv[0] << ": target does not support generation of this"
359 if (Out != &fouts()) delete Out;
360 // And the Out file is empty and useless, so remove it now.
361 sys::Path(OutputFilename).eraseFromDisk();
363 case FileModel::AsmFile:
365 case FileModel::MachOFile:
366 OCE = AddMachOWriter(Passes, *Out, Target);
368 case FileModel::ElfFile:
369 OCE = AddELFWriter(Passes, *Out, Target);
373 if (Target.addPassesToEmitFileFinish(Passes, OCE, OLvl)) {
374 errs() << argv[0] << ": target does not support generation of this"
376 if (Out != &fouts()) delete Out;
377 // And the Out file is empty and useless, so remove it now.
378 sys::Path(OutputFilename).eraseFromDisk();
382 Passes.doInitialization();
384 // Run our queue of passes all at once now, efficiently.
385 // TODO: this could lazily stream functions out of the module.
386 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
387 if (!I->isDeclaration()) {
389 I->addFnAttr(Attribute::NoRedZone);
390 if (NoImplicitFloats)
391 I->addFnAttr(Attribute::NoImplicitFloat);
395 Passes.doFinalization();
398 // Delete the ostream if it's not a stdout stream
399 if (Out != &fouts()) delete Out;