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/LinkAllVMCore.h"
27 #include "llvm/Support/CommandLine.h"
28 #include "llvm/Support/Debug.h"
29 #include "llvm/Support/FileUtilities.h"
30 #include "llvm/Support/FormattedStream.h"
31 #include "llvm/Support/ManagedStatic.h"
32 #include "llvm/Support/MemoryBuffer.h"
33 #include "llvm/Support/PluginLoader.h"
34 #include "llvm/Support/PrettyStackTrace.h"
35 #include "llvm/System/Host.h"
36 #include "llvm/System/Signals.h"
37 #include "llvm/Target/SubtargetFeature.h"
38 #include "llvm/Target/TargetData.h"
39 #include "llvm/Target/TargetMachine.h"
40 #include "llvm/Target/TargetRegistry.h"
41 #include "llvm/Target/TargetSelect.h"
42 #include "llvm/Transforms/Scalar.h"
46 // General options for llc. Other pass-specific options are specified
47 // within the corresponding llc passes, and target-specific options
48 // and back-end code generation options are specified with the target machine.
50 static cl::opt<std::string>
51 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
53 static cl::opt<std::string>
54 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
57 Force("f", cl::desc("Enable binary output on terminals"));
59 // Determine optimization level.
62 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
68 static cl::opt<std::string>
69 TargetTriple("mtriple", cl::desc("Override target triple for module"));
71 static cl::opt<std::string>
72 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
74 static cl::opt<std::string>
76 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
77 cl::value_desc("cpu-name"),
80 static cl::list<std::string>
83 cl::desc("Target specific attributes (-mattr=help for details)"),
84 cl::value_desc("a1,+a2,-a3,..."));
86 cl::opt<TargetMachine::CodeGenFileType>
87 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
88 cl::desc("Choose a file type (not all types are supported by all targets):"),
90 clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
91 "Emit an assembly ('.s') file"),
92 clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
93 "Emit a native object ('.o') file [experimental]"),
94 clEnumValN(TargetMachine::CGFT_Null, "null",
95 "Emit nothing, for performance testing"),
98 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
99 cl::desc("Do not verify input module"));
103 DisableRedZone("disable-red-zone",
104 cl::desc("Do not emit code that uses the red zone."),
108 NoImplicitFloats("no-implicit-float",
109 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
112 // GetFileNameRoot - Helper function to get the basename of a filename.
113 static inline std::string
114 GetFileNameRoot(const std::string &InputFilename) {
115 std::string IFN = InputFilename;
116 std::string outputFilename;
117 int Len = IFN.length();
120 ((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
121 (IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
122 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
124 outputFilename = IFN;
126 return outputFilename;
129 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
130 const char *ProgName) {
131 if (OutputFilename != "") {
132 if (OutputFilename == "-")
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 = "-";
159 OutputFilename = GetFileNameRoot(InputFilename);
163 default: assert(0 && "Unknown file type");
164 case TargetMachine::CGFT_AssemblyFile:
165 if (TargetName[0] == 'c') {
166 if (TargetName[1] == 0)
167 OutputFilename += ".cbe.c";
168 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
169 OutputFilename += ".cpp";
171 OutputFilename += ".s";
173 OutputFilename += ".s";
175 case TargetMachine::CGFT_ObjectFile:
176 OutputFilename += ".o";
179 case TargetMachine::CGFT_Null:
180 OutputFilename += ".null";
185 // Make sure that the Out file gets unlinked from the disk if we get a
187 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
190 unsigned OpenFlags = 0;
191 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
192 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(), error,
194 if (!error.empty()) {
195 errs() << error << '\n';
200 formatted_raw_ostream *Out =
201 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
206 // main - Entry point for the llc compiler.
208 int main(int argc, char **argv) {
209 sys::PrintStackTraceOnErrorSignal();
210 PrettyStackTraceProgram X(argc, argv);
212 // Enable debug stream buffering.
213 EnableDebugBuffering = true;
215 LLVMContext &Context = getGlobalContext();
216 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
218 // Initialize targets first, so that --version shows registered targets.
219 InitializeAllTargets();
220 InitializeAllAsmPrinters();
222 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
224 // Load the module to be compiled...
226 std::auto_ptr<Module> M;
228 M.reset(ParseIRFile(InputFilename, Err, Context));
230 Err.Print(argv[0], errs());
233 Module &mod = *M.get();
235 // If we are supposed to override the target triple, do so now.
236 if (!TargetTriple.empty())
237 mod.setTargetTriple(TargetTriple);
239 Triple TheTriple(mod.getTargetTriple());
240 if (TheTriple.getTriple().empty())
241 TheTriple.setTriple(sys::getHostTriple());
243 // Allocate target machine. First, check whether the user has explicitly
244 // specified an architecture to compile for. If so we have to look it up by
245 // name, because it might be a backend that has no mapping to a target triple.
246 const Target *TheTarget = 0;
247 if (!MArch.empty()) {
248 for (TargetRegistry::iterator it = TargetRegistry::begin(),
249 ie = TargetRegistry::end(); it != ie; ++it) {
250 if (MArch == it->getName()) {
257 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
261 // Adjust the triple to match (if known), otherwise stick with the
262 // module/host triple.
263 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
264 if (Type != Triple::UnknownArch)
265 TheTriple.setArch(Type);
268 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
269 if (TheTarget == 0) {
270 errs() << argv[0] << ": error auto-selecting target for module '"
271 << Err << "'. Please use the -march option to explicitly "
272 << "pick a target.\n";
277 // Package up features to be passed to target/subtarget
278 std::string FeaturesStr;
279 if (MCPU.size() || MAttrs.size()) {
280 SubtargetFeatures Features;
281 Features.setCPU(MCPU);
282 for (unsigned i = 0; i != MAttrs.size(); ++i)
283 Features.AddFeature(MAttrs[i]);
284 FeaturesStr = Features.getString();
287 std::auto_ptr<TargetMachine>
288 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
289 assert(target.get() && "Could not allocate target machine!");
290 TargetMachine &Target = *target.get();
292 // Figure out where we are going to send the output...
293 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
294 if (Out == 0) return 1;
296 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
299 errs() << argv[0] << ": invalid optimization level.\n";
302 case '0': OLvl = CodeGenOpt::None; break;
303 case '1': OLvl = CodeGenOpt::Less; break;
304 case '2': OLvl = CodeGenOpt::Default; break;
305 case '3': OLvl = CodeGenOpt::Aggressive; break;
308 // If this target requires addPassesToEmitWholeFile, do it now. This is
309 // used by strange things like the C backend.
310 if (Target.WantsWholeFile()) {
313 // Add the target data from the target machine, if it exists, or the module.
314 if (const TargetData *TD = Target.getTargetData())
315 PM.add(new TargetData(*TD));
317 PM.add(new TargetData(&mod));
320 PM.add(createVerifierPass());
322 // Ask the target to add backend passes as necessary.
323 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
324 errs() << argv[0] << ": target does not support generation of this"
326 if (Out != &fouts()) delete Out;
327 // And the Out file is empty and useless, so remove it now.
328 sys::Path(OutputFilename).eraseFromDisk();
333 // Build up all of the passes that we want to do to the module.
334 FunctionPassManager Passes(M.get());
336 // Add the target data from the target machine, if it exists, or the module.
337 if (const TargetData *TD = Target.getTargetData())
338 Passes.add(new TargetData(*TD));
340 Passes.add(new TargetData(&mod));
344 Passes.add(createVerifierPass());
347 // Override default to generate verbose assembly.
348 Target.setAsmVerbosityDefault(true);
350 if (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
351 errs() << argv[0] << ": target does not support generation of this"
353 if (Out != &fouts()) delete Out;
354 // And the Out file is empty and useless, so remove it now.
355 sys::Path(OutputFilename).eraseFromDisk();
359 Passes.doInitialization();
361 // Run our queue of passes all at once now, efficiently.
362 // TODO: this could lazily stream functions out of the module.
363 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
364 if (!I->isDeclaration()) {
366 I->addFnAttr(Attribute::NoRedZone);
367 if (NoImplicitFloats)
368 I->addFnAttr(Attribute::NoImplicitFloat);
372 Passes.doFinalization();
375 // Delete the ostream if it's not a stdout stream
376 if (Out != &fouts()) delete Out;