1//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 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. 13// 14//===----------------------------------------------------------------------===// 15 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/Support/IRReader.h" 22#include "llvm/CodeGen/LinkAllAsmWriterComponents.h" 23#include "llvm/CodeGen/LinkAllCodegenComponents.h" 24#include "llvm/Config/config.h" 25#include "llvm/Support/CommandLine.h" 26#include "llvm/Support/Debug.h" 27#include "llvm/Support/FormattedStream.h" 28#include "llvm/Support/ManagedStatic.h" 29#include "llvm/Support/PluginLoader.h" 30#include "llvm/Support/PrettyStackTrace.h" 31#include "llvm/Support/ToolOutputFile.h" 32#include "llvm/Support/Host.h" 33#include "llvm/Support/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" 39#include <memory> 40using namespace llvm; 41 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. 45// 46static cl::opt<std::string> 47InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-")); 48 49static cl::opt<std::string> 50OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename")); 51 52// Determine optimization level. 53static cl::opt<char> 54OptLevel("O", 55 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] " 56 "(default = '-O2')"), 57 cl::Prefix, 58 cl::ZeroOrMore, 59 cl::init(' ')); 60 61static cl::opt<std::string> 62TargetTriple("mtriple", cl::desc("Override target triple for module")); 63 64static cl::opt<std::string> 65MArch("march", cl::desc("Architecture to generate code for (see --version)")); 66 67static cl::opt<std::string> 68MCPU("mcpu", 69 cl::desc("Target a specific cpu type (-mcpu=help for details)"), 70 cl::value_desc("cpu-name"), 71 cl::init("")); 72 73static cl::list<std::string> 74MAttrs("mattr", 75 cl::CommaSeparated, 76 cl::desc("Target specific attributes (-mattr=help for details)"), 77 cl::value_desc("a1,+a2,-a3,...")); 78 79static cl::opt<bool> 80RelaxAll("mc-relax-all", 81 cl::desc("When used with filetype=obj, " 82 "relax all fixups in the emitted object file")); 83 84cl::opt<TargetMachine::CodeGenFileType> 85FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile), 86 cl::desc("Choose a file type (not all types are supported by all targets):"), 87 cl::values( 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"), 94 clEnumValEnd)); 95 96cl::opt<bool> NoVerify("disable-verify", cl::Hidden, 97 cl::desc("Do not verify input module")); 98 99cl::opt<bool> DisableDotLoc("disable-dot-loc", cl::Hidden, 100 cl::desc("Do not use .loc entries")); 101 102cl::opt<bool> DisableCFI("disable-cfi", cl::Hidden, 103 cl::desc("Do not use .cfi_* directives")); 104 105static cl::opt<bool> 106DisableRedZone("disable-red-zone", 107 cl::desc("Do not emit code that uses the red zone."), 108 cl::init(false)); 109 |
110// GetFileNameRoot - Helper function to get the basename of a filename. 111static inline std::string 112GetFileNameRoot(const std::string &InputFilename) { 113 std::string IFN = InputFilename; 114 std::string outputFilename; 115 int Len = IFN.length(); 116 if ((Len > 2) && 117 IFN[Len-3] == '.' && 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/ 121 } else { 122 outputFilename = IFN; 123 } 124 return outputFilename; 125} 126 127static tool_output_file *GetOutputStream(const char *TargetName, 128 Triple::OSType OS, 129 const char *ProgName) { 130 // If we don't yet have an output filename, make one. 131 if (OutputFilename.empty()) { 132 if (InputFilename == "-") 133 OutputFilename = "-"; 134 else { 135 OutputFilename = GetFileNameRoot(InputFilename); 136 137 switch (FileType) { 138 default: assert(0 && "Unknown file type"); 139 case TargetMachine::CGFT_AssemblyFile: 140 if (TargetName[0] == 'c') { 141 if (TargetName[1] == 0) 142 OutputFilename += ".cbe.c"; 143 else if (TargetName[1] == 'p' && TargetName[2] == 'p') 144 OutputFilename += ".cpp"; 145 else 146 OutputFilename += ".s"; 147 } else 148 OutputFilename += ".s"; 149 break; 150 case TargetMachine::CGFT_ObjectFile: 151 if (OS == Triple::Win32) 152 OutputFilename += ".obj"; 153 else 154 OutputFilename += ".o"; 155 break; 156 case TargetMachine::CGFT_Null: 157 OutputFilename += ".null"; 158 break; 159 } 160 } 161 } 162 163 // Decide if we need "binary" output. 164 bool Binary = false; 165 switch (FileType) { 166 default: assert(0 && "Unknown file type"); 167 case TargetMachine::CGFT_AssemblyFile: 168 break; 169 case TargetMachine::CGFT_ObjectFile: 170 case TargetMachine::CGFT_Null: 171 Binary = true; 172 break; 173 } 174 175 // Open the file. 176 std::string error; 177 unsigned OpenFlags = 0; 178 if (Binary) OpenFlags |= raw_fd_ostream::F_Binary; 179 tool_output_file *FDOut = new tool_output_file(OutputFilename.c_str(), error, 180 OpenFlags); 181 if (!error.empty()) { 182 errs() << error << '\n'; 183 delete FDOut; 184 return 0; 185 } 186 187 return FDOut; 188} 189 190// main - Entry point for the llc compiler. 191// 192int main(int argc, char **argv) { 193 sys::PrintStackTraceOnErrorSignal(); 194 PrettyStackTraceProgram X(argc, argv); 195 196 // Enable debug stream buffering. 197 EnableDebugBuffering = true; 198 199 LLVMContext &Context = getGlobalContext(); 200 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit. 201 202 // Initialize targets first, so that --version shows registered targets. 203 InitializeAllTargets(); 204 InitializeAllAsmPrinters(); 205 InitializeAllAsmParsers(); 206 207 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n"); 208 209 // Load the module to be compiled... 210 SMDiagnostic Err; 211 std::auto_ptr<Module> M; 212 213 M.reset(ParseIRFile(InputFilename, Err, Context)); 214 if (M.get() == 0) { 215 Err.Print(argv[0], errs()); 216 return 1; 217 } 218 Module &mod = *M.get(); 219 220 // If we are supposed to override the target triple, do so now. 221 if (!TargetTriple.empty()) 222 mod.setTargetTriple(Triple::normalize(TargetTriple)); 223 224 Triple TheTriple(mod.getTargetTriple()); 225 if (TheTriple.getTriple().empty()) 226 TheTriple.setTriple(sys::getHostTriple()); 227 228 // Allocate target machine. First, check whether the user has explicitly 229 // specified an architecture to compile for. If so we have to look it up by 230 // name, because it might be a backend that has no mapping to a target triple. 231 const Target *TheTarget = 0; 232 if (!MArch.empty()) { 233 for (TargetRegistry::iterator it = TargetRegistry::begin(), 234 ie = TargetRegistry::end(); it != ie; ++it) { 235 if (MArch == it->getName()) { 236 TheTarget = &*it; 237 break; 238 } 239 } 240 241 if (!TheTarget) { 242 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n"; 243 return 1; 244 } 245 246 // Adjust the triple to match (if known), otherwise stick with the 247 // module/host triple. 248 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch); 249 if (Type != Triple::UnknownArch) 250 TheTriple.setArch(Type); 251 } else { 252 std::string Err; 253 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err); 254 if (TheTarget == 0) { 255 errs() << argv[0] << ": error auto-selecting target for module '" 256 << Err << "'. Please use the -march option to explicitly " 257 << "pick a target.\n"; 258 return 1; 259 } 260 } 261 262 // Package up features to be passed to target/subtarget 263 std::string FeaturesStr; 264 if (MCPU.size() || MAttrs.size()) { 265 SubtargetFeatures Features; 266 Features.setCPU(MCPU); 267 for (unsigned i = 0; i != MAttrs.size(); ++i) 268 Features.AddFeature(MAttrs[i]); 269 FeaturesStr = Features.getString(); 270 } 271 272 std::auto_ptr<TargetMachine> 273 target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr)); 274 assert(target.get() && "Could not allocate target machine!"); 275 TargetMachine &Target = *target.get(); 276 277 if (DisableDotLoc) 278 Target.setMCUseLoc(false); 279 280 if (DisableCFI) 281 Target.setMCUseCFI(false); 282 283 // Disable .loc support for older OS X versions. 284 if (TheTriple.isMacOSX() && 285 TheTriple.isMacOSXVersionLT(10, 6)) 286 Target.setMCUseLoc(false); 287 288 // Figure out where we are going to send the output... 289 OwningPtr<tool_output_file> Out 290 (GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0])); 291 if (!Out) return 1; 292 293 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 294 switch (OptLevel) { 295 default: 296 errs() << argv[0] << ": invalid optimization level.\n"; 297 return 1; 298 case ' ': break; 299 case '0': OLvl = CodeGenOpt::None; break; 300 case '1': OLvl = CodeGenOpt::Less; break; 301 case '2': OLvl = CodeGenOpt::Default; break; 302 case '3': OLvl = CodeGenOpt::Aggressive; break; 303 } 304 305 // Build up all of the passes that we want to do to the module. 306 PassManager PM; 307 308 // Add the target data from the target machine, if it exists, or the module. 309 if (const TargetData *TD = Target.getTargetData()) 310 PM.add(new TargetData(*TD)); 311 else 312 PM.add(new TargetData(&mod)); 313 314 // Override default to generate verbose assembly. 315 Target.setAsmVerbosityDefault(true); 316 317 if (RelaxAll) { 318 if (FileType != TargetMachine::CGFT_ObjectFile) 319 errs() << argv[0] 320 << ": warning: ignoring -mc-relax-all because filetype != obj"; 321 else 322 Target.setMCRelaxAll(true); 323 } 324 325 { 326 formatted_raw_ostream FOS(Out->os()); 327 328 // Ask the target to add backend passes as necessary. 329 if (Target.addPassesToEmitFile(PM, FOS, FileType, OLvl, NoVerify)) { 330 errs() << argv[0] << ": target does not support generation of this" 331 << " file type!\n"; 332 return 1; 333 } 334 335 // Before executing passes, print the final values of the LLVM options. 336 cl::PrintOptionValues(); 337 338 PM.run(mod); 339 } 340 341 // Declare success. 342 Out->keep(); 343 344 return 0; 345} |