llc.cpp revision 224133
1262706Serwin//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===// 2135446Strhodes// 3135446Strhodes// The LLVM Compiler Infrastructure 4193149Sdougb// 5135446Strhodes// This file is distributed under the University of Illinois Open Source 6135446Strhodes// License. See LICENSE.TXT for details. 7135446Strhodes// 8135446Strhodes//===----------------------------------------------------------------------===// 9135446Strhodes// 10135446Strhodes// This is the llc code generator driver. It provides a convenient 11135446Strhodes// command-line interface for generating native assembly-language code 12135446Strhodes// or C code, given LLVM bitcode. 13135446Strhodes// 14135446Strhodes//===----------------------------------------------------------------------===// 15135446Strhodes 16234010Sdougb#include "llvm/LLVMContext.h" 17135446Strhodes#include "llvm/Module.h" 18135446Strhodes#include "llvm/PassManager.h" 19135446Strhodes#include "llvm/Pass.h" 20135446Strhodes#include "llvm/ADT/Triple.h" 21135446Strhodes#include "llvm/Support/IRReader.h" 22135446Strhodes#include "llvm/CodeGen/LinkAllAsmWriterComponents.h" 23135446Strhodes#include "llvm/CodeGen/LinkAllCodegenComponents.h" 24135446Strhodes#include "llvm/Config/config.h" 25135446Strhodes#include "llvm/MC/SubtargetFeature.h" 26135446Strhodes#include "llvm/Support/CommandLine.h" 27135446Strhodes#include "llvm/Support/Debug.h" 28135446Strhodes#include "llvm/Support/FormattedStream.h" 29224092Sdougb#include "llvm/Support/ManagedStatic.h" 30224092Sdougb#include "llvm/Support/PluginLoader.h" 31153816Sdougb#include "llvm/Support/PrettyStackTrace.h" 32262706Serwin#include "llvm/Support/ToolOutputFile.h" 33262706Serwin#include "llvm/Support/Host.h" 34262706Serwin#include "llvm/Support/Signals.h" 35224092Sdougb#include "llvm/Target/TargetData.h" 36224092Sdougb#include "llvm/Target/TargetMachine.h" 37193149Sdougb#include "llvm/Target/TargetRegistry.h" 38254402Serwin#include "llvm/Target/TargetSelect.h" 39262706Serwin#include <memory> 40262706Serwinusing namespace llvm; 41262706Serwin 42193149Sdougb// General options for llc. Other pass-specific options are specified 43135446Strhodes// within the corresponding llc passes, and target-specific options 44135446Strhodes// and back-end code generation options are specified with the target machine. 45135446Strhodes// 46135446Strhodesstatic cl::opt<std::string> 47135446StrhodesInputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-")); 48135446Strhodes 49135446Strhodesstatic cl::opt<std::string> 50135446StrhodesOutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename")); 51135446Strhodes 52135446Strhodes// Determine optimization level. 53135446Strhodesstatic cl::opt<char> 54135446StrhodesOptLevel("O", 55135446Strhodes cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] " 56135446Strhodes "(default = '-O2')"), 57135446Strhodes cl::Prefix, 58135446Strhodes cl::ZeroOrMore, 59135446Strhodes 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 InitializeAllMCAsmInfos(); 205 InitializeAllMCInstrInfos(); 206 InitializeAllMCSubtargetInfos(); 207 InitializeAllAsmPrinters(); 208 InitializeAllAsmParsers(); 209 210 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n"); 211 212 // Load the module to be compiled... 213 SMDiagnostic Err; 214 std::auto_ptr<Module> M; 215 216 M.reset(ParseIRFile(InputFilename, Err, Context)); 217 if (M.get() == 0) { 218 Err.Print(argv[0], errs()); 219 return 1; 220 } 221 Module &mod = *M.get(); 222 223 // If we are supposed to override the target triple, do so now. 224 if (!TargetTriple.empty()) 225 mod.setTargetTriple(Triple::normalize(TargetTriple)); 226 227 Triple TheTriple(mod.getTargetTriple()); 228 if (TheTriple.getTriple().empty()) 229 TheTriple.setTriple(sys::getHostTriple()); 230 231 // Allocate target machine. First, check whether the user has explicitly 232 // specified an architecture to compile for. If so we have to look it up by 233 // name, because it might be a backend that has no mapping to a target triple. 234 const Target *TheTarget = 0; 235 if (!MArch.empty()) { 236 for (TargetRegistry::iterator it = TargetRegistry::begin(), 237 ie = TargetRegistry::end(); it != ie; ++it) { 238 if (MArch == it->getName()) { 239 TheTarget = &*it; 240 break; 241 } 242 } 243 244 if (!TheTarget) { 245 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n"; 246 return 1; 247 } 248 249 // Adjust the triple to match (if known), otherwise stick with the 250 // module/host triple. 251 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch); 252 if (Type != Triple::UnknownArch) 253 TheTriple.setArch(Type); 254 } else { 255 std::string Err; 256 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err); 257 if (TheTarget == 0) { 258 errs() << argv[0] << ": error auto-selecting target for module '" 259 << Err << "'. Please use the -march option to explicitly " 260 << "pick a target.\n"; 261 return 1; 262 } 263 } 264 265 // Package up features to be passed to target/subtarget 266 std::string FeaturesStr; 267 if (MAttrs.size()) { 268 SubtargetFeatures Features; 269 for (unsigned i = 0; i != MAttrs.size(); ++i) 270 Features.AddFeature(MAttrs[i]); 271 FeaturesStr = Features.getString(); 272 } 273 274 std::auto_ptr<TargetMachine> 275 target(TheTarget->createTargetMachine(TheTriple.getTriple(), MCPU, 276 FeaturesStr)); 277 assert(target.get() && "Could not allocate target machine!"); 278 TargetMachine &Target = *target.get(); 279 280 if (DisableDotLoc) 281 Target.setMCUseLoc(false); 282 283 if (DisableCFI) 284 Target.setMCUseCFI(false); 285 286 // Disable .loc support for older OS X versions. 287 if (TheTriple.isMacOSX() && 288 TheTriple.isMacOSXVersionLT(10, 6)) 289 Target.setMCUseLoc(false); 290 291 // Figure out where we are going to send the output... 292 OwningPtr<tool_output_file> Out 293 (GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0])); 294 if (!Out) return 1; 295 296 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 297 switch (OptLevel) { 298 default: 299 errs() << argv[0] << ": invalid optimization level.\n"; 300 return 1; 301 case ' ': break; 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; 306 } 307 308 // Build up all of the passes that we want to do to the module. 309 PassManager PM; 310 311 // 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)); 314 else 315 PM.add(new TargetData(&mod)); 316 317 // Override default to generate verbose assembly. 318 Target.setAsmVerbosityDefault(true); 319 320 if (RelaxAll) { 321 if (FileType != TargetMachine::CGFT_ObjectFile) 322 errs() << argv[0] 323 << ": warning: ignoring -mc-relax-all because filetype != obj"; 324 else 325 Target.setMCRelaxAll(true); 326 } 327 328 { 329 formatted_raw_ostream FOS(Out->os()); 330 331 // Ask the target to add backend passes as necessary. 332 if (Target.addPassesToEmitFile(PM, FOS, FileType, OLvl, NoVerify)) { 333 errs() << argv[0] << ": target does not support generation of this" 334 << " file type!\n"; 335 return 1; 336 } 337 338 // Before executing passes, print the final values of the LLVM options. 339 cl::PrintOptionValues(); 340 341 PM.run(mod); 342 } 343 344 // Declare success. 345 Out->keep(); 346 347 return 0; 348} 349