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,..."));
79 cl::opt<TargetMachine::CodeGenFileType>
80 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
81 cl::desc("Choose a file type (not all types are supported by all targets):"),
83 clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
84 "Emit an assembly ('.s') file"),
85 clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
86 "Emit a native object ('.o') file [experimental]"),
87 clEnumValN(TargetMachine::CGFT_Null, "null",
88 "Emit nothing, for performance testing"),
91 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
92 cl::desc("Do not verify input module"));
96 DisableRedZone("disable-red-zone",
97 cl::desc("Do not emit code that uses the red zone."),
101 NoImplicitFloats("no-implicit-float",
102 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
105 // GetFileNameRoot - Helper function to get the basename of a filename.
106 static inline std::string
107 GetFileNameRoot(const std::string &InputFilename) {
108 std::string IFN = InputFilename;
109 std::string outputFilename;
110 int Len = IFN.length();
113 ((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
114 (IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
115 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
117 outputFilename = IFN;
119 return outputFilename;
122 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
123 const char *ProgName) {
124 if (OutputFilename != "") {
125 if (OutputFilename == "-")
128 // Make sure that the Out file gets unlinked from the disk if we get a
130 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
133 raw_fd_ostream *FDOut =
134 new raw_fd_ostream(OutputFilename.c_str(), error,
135 raw_fd_ostream::F_Binary);
136 if (!error.empty()) {
137 errs() << error << '\n';
141 formatted_raw_ostream *Out =
142 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
147 if (InputFilename == "-") {
148 OutputFilename = "-";
152 OutputFilename = GetFileNameRoot(InputFilename);
156 default: assert(0 && "Unknown file type");
157 case TargetMachine::CGFT_AssemblyFile:
158 if (TargetName[0] == 'c') {
159 if (TargetName[1] == 0)
160 OutputFilename += ".cbe.c";
161 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
162 OutputFilename += ".cpp";
164 OutputFilename += ".s";
166 OutputFilename += ".s";
168 case TargetMachine::CGFT_ObjectFile:
169 OutputFilename += ".o";
172 case TargetMachine::CGFT_Null:
173 OutputFilename += ".null";
178 // Make sure that the Out file gets unlinked from the disk if we get a
180 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
183 unsigned OpenFlags = 0;
184 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
185 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(), error,
187 if (!error.empty()) {
188 errs() << error << '\n';
193 formatted_raw_ostream *Out =
194 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
199 // main - Entry point for the llc compiler.
201 int main(int argc, char **argv) {
202 sys::PrintStackTraceOnErrorSignal();
203 PrettyStackTraceProgram X(argc, argv);
205 // Enable debug stream buffering.
206 EnableDebugBuffering = true;
208 LLVMContext &Context = getGlobalContext();
209 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
211 // Initialize targets first, so that --version shows registered targets.
212 InitializeAllTargets();
213 InitializeAllAsmPrinters();
214 InitializeAllAsmParsers();
216 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
218 // Load the module to be compiled...
220 std::auto_ptr<Module> M;
222 M.reset(ParseIRFile(InputFilename, Err, Context));
224 Err.Print(argv[0], errs());
227 Module &mod = *M.get();
229 // If we are supposed to override the target triple, do so now.
230 if (!TargetTriple.empty())
231 mod.setTargetTriple(TargetTriple);
233 Triple TheTriple(mod.getTargetTriple());
234 if (TheTriple.getTriple().empty())
235 TheTriple.setTriple(sys::getHostTriple());
237 // Allocate target machine. First, check whether the user has explicitly
238 // specified an architecture to compile for. If so we have to look it up by
239 // name, because it might be a backend that has no mapping to a target triple.
240 const Target *TheTarget = 0;
241 if (!MArch.empty()) {
242 for (TargetRegistry::iterator it = TargetRegistry::begin(),
243 ie = TargetRegistry::end(); it != ie; ++it) {
244 if (MArch == it->getName()) {
251 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
255 // Adjust the triple to match (if known), otherwise stick with the
256 // module/host triple.
257 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
258 if (Type != Triple::UnknownArch)
259 TheTriple.setArch(Type);
262 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
263 if (TheTarget == 0) {
264 errs() << argv[0] << ": error auto-selecting target for module '"
265 << Err << "'. Please use the -march option to explicitly "
266 << "pick a target.\n";
271 // Package up features to be passed to target/subtarget
272 std::string FeaturesStr;
273 if (MCPU.size() || MAttrs.size()) {
274 SubtargetFeatures Features;
275 Features.setCPU(MCPU);
276 for (unsigned i = 0; i != MAttrs.size(); ++i)
277 Features.AddFeature(MAttrs[i]);
278 FeaturesStr = Features.getString();
281 std::auto_ptr<TargetMachine>
282 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
283 assert(target.get() && "Could not allocate target machine!");
284 TargetMachine &Target = *target.get();
286 // Figure out where we are going to send the output...
287 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
288 if (Out == 0) return 1;
290 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
293 errs() << argv[0] << ": invalid optimization level.\n";
296 case '0': OLvl = CodeGenOpt::None; break;
297 case '1': OLvl = CodeGenOpt::Less; break;
298 case '2': OLvl = CodeGenOpt::Default; break;
299 case '3': OLvl = CodeGenOpt::Aggressive; break;
302 // Request that addPassesToEmitFile run the Verifier after running
303 // passes which modify the IR.
305 bool DisableVerify = false;
307 bool DisableVerify = true;
310 // If this target requires addPassesToEmitWholeFile, do it now. This is
311 // used by strange things like the C backend.
312 if (Target.WantsWholeFile()) {
315 // Add the target data from the target machine, if it exists, or the module.
316 if (const TargetData *TD = Target.getTargetData())
317 PM.add(new TargetData(*TD));
319 PM.add(new TargetData(&mod));
322 PM.add(createVerifierPass());
324 // Ask the target to add backend passes as necessary.
325 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl,
327 errs() << argv[0] << ": target does not support generation of this"
329 if (Out != &fouts()) delete Out;
330 // And the Out file is empty and useless, so remove it now.
331 sys::Path(OutputFilename).eraseFromDisk();
336 // Build up all of the passes that we want to do to the module.
337 FunctionPassManager Passes(M.get());
339 // Add the target data from the target machine, if it exists, or the module.
340 if (const TargetData *TD = Target.getTargetData())
341 Passes.add(new TargetData(*TD));
343 Passes.add(new TargetData(&mod));
347 Passes.add(createVerifierPass());
350 // Override default to generate verbose assembly.
351 Target.setAsmVerbosityDefault(true);
353 if (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl,
355 errs() << argv[0] << ": target does not support generation of this"
357 if (Out != &fouts()) delete Out;
358 // And the Out file is empty and useless, so remove it now.
359 sys::Path(OutputFilename).eraseFromDisk();
363 Passes.doInitialization();
365 // Run our queue of passes all at once now, efficiently.
366 // TODO: this could lazily stream functions out of the module.
367 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
368 if (!I->isDeclaration()) {
370 I->addFnAttr(Attribute::NoRedZone);
371 if (NoImplicitFloats)
372 I->addFnAttr(Attribute::NoImplicitFloat);
376 Passes.doFinalization();
379 // Delete the ostream if it's not a stdout stream
380 if (Out != &fouts()) delete Out;