1 //===- ExecutionDriver.cpp - Allow execution of LLVM program --------------===// 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 file contains code used to execute the program utilizing one of the 11 // various ways of running LLVM bitcode. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "BugDriver.h" 16 #include "ToolRunner.h" 17 #include "llvm/Support/CommandLine.h" 18 #include "llvm/Support/Debug.h" 19 #include "llvm/Support/FileUtilities.h" 20 #include "llvm/Support/SystemUtils.h" 21 #include "llvm/Support/raw_ostream.h" 22 #include <fstream> 23 24 using namespace llvm; 25 26 namespace { 27 // OutputType - Allow the user to specify the way code should be run, to test 28 // for miscompilation. 29 // 30 enum OutputType { 31 AutoPick, RunLLI, RunJIT, RunLLC, RunLLCIA, LLC_Safe, CompileCustom, Custom 32 }; 33 34 cl::opt<double> 35 AbsTolerance("abs-tolerance", cl::desc("Absolute error tolerated"), 36 cl::init(0.0)); 37 cl::opt<double> 38 RelTolerance("rel-tolerance", cl::desc("Relative error tolerated"), 39 cl::init(0.0)); 40 41 cl::opt<OutputType> 42 InterpreterSel(cl::desc("Specify the \"test\" i.e. suspect back-end:"), 43 cl::values(clEnumValN(AutoPick, "auto", "Use best guess"), 44 clEnumValN(RunLLI, "run-int", 45 "Execute with the interpreter"), 46 clEnumValN(RunJIT, "run-jit", "Execute with JIT"), 47 clEnumValN(RunLLC, "run-llc", "Compile with LLC"), 48 clEnumValN(RunLLCIA, "run-llc-ia", 49 "Compile with LLC with integrated assembler"), 50 clEnumValN(LLC_Safe, "llc-safe", "Use LLC for all"), 51 clEnumValN(CompileCustom, "compile-custom", 52 "Use -compile-command to define a command to " 53 "compile the bitcode. Useful to avoid linking."), 54 clEnumValN(Custom, "run-custom", 55 "Use -exec-command to define a command to execute " 56 "the bitcode. Useful for cross-compilation."), 57 clEnumValEnd), 58 cl::init(AutoPick)); 59 60 cl::opt<OutputType> 61 SafeInterpreterSel(cl::desc("Specify \"safe\" i.e. known-good backend:"), 62 cl::values(clEnumValN(AutoPick, "safe-auto", "Use best guess"), 63 clEnumValN(RunLLC, "safe-run-llc", "Compile with LLC"), 64 clEnumValN(Custom, "safe-run-custom", 65 "Use -exec-command to define a command to execute " 66 "the bitcode. Useful for cross-compilation."), 67 clEnumValEnd), 68 cl::init(AutoPick)); 69 70 cl::opt<std::string> 71 SafeInterpreterPath("safe-path", 72 cl::desc("Specify the path to the \"safe\" backend program"), 73 cl::init("")); 74 75 cl::opt<bool> 76 AppendProgramExitCode("append-exit-code", 77 cl::desc("Append the exit code to the output so it gets diff'd too"), 78 cl::init(false)); 79 80 cl::opt<std::string> 81 InputFile("input", cl::init("/dev/null"), 82 cl::desc("Filename to pipe in as stdin (default: /dev/null)")); 83 84 cl::list<std::string> 85 AdditionalSOs("additional-so", 86 cl::desc("Additional shared objects to load " 87 "into executing programs")); 88 89 cl::list<std::string> 90 AdditionalLinkerArgs("Xlinker", 91 cl::desc("Additional arguments to pass to the linker")); 92 93 cl::opt<std::string> 94 CustomCompileCommand("compile-command", cl::init("llc"), 95 cl::desc("Command to compile the bitcode (use with -compile-custom) " 96 "(default: llc)")); 97 98 cl::opt<std::string> 99 CustomExecCommand("exec-command", cl::init("simulate"), 100 cl::desc("Command to execute the bitcode (use with -run-custom) " 101 "(default: simulate)")); 102 } 103 104 namespace llvm { 105 // Anything specified after the --args option are taken as arguments to the 106 // program being debugged. 107 cl::list<std::string> 108 InputArgv("args", cl::Positional, cl::desc("<program arguments>..."), 109 cl::ZeroOrMore, cl::PositionalEatsArgs); 110 111 cl::opt<std::string> 112 OutputPrefix("output-prefix", cl::init("bugpoint"), 113 cl::desc("Prefix to use for outputs (default: 'bugpoint')")); 114 } 115 116 namespace { 117 cl::list<std::string> 118 ToolArgv("tool-args", cl::Positional, cl::desc("<tool arguments>..."), 119 cl::ZeroOrMore, cl::PositionalEatsArgs); 120 121 cl::list<std::string> 122 SafeToolArgv("safe-tool-args", cl::Positional, 123 cl::desc("<safe-tool arguments>..."), 124 cl::ZeroOrMore, cl::PositionalEatsArgs); 125 126 cl::opt<std::string> 127 GCCBinary("gcc", cl::init("gcc"), 128 cl::desc("The gcc binary to use. (default 'gcc')")); 129 130 cl::list<std::string> 131 GCCToolArgv("gcc-tool-args", cl::Positional, 132 cl::desc("<gcc-tool arguments>..."), 133 cl::ZeroOrMore, cl::PositionalEatsArgs); 134 } 135 136 //===----------------------------------------------------------------------===// 137 // BugDriver method implementation 138 // 139 140 /// initializeExecutionEnvironment - This method is used to set up the 141 /// environment for executing LLVM programs. 142 /// 143 bool BugDriver::initializeExecutionEnvironment() { 144 outs() << "Initializing execution environment: "; 145 146 // Create an instance of the AbstractInterpreter interface as specified on 147 // the command line 148 SafeInterpreter = nullptr; 149 std::string Message; 150 151 switch (InterpreterSel) { 152 case AutoPick: 153 if (!Interpreter) { 154 InterpreterSel = RunJIT; 155 Interpreter = AbstractInterpreter::createJIT(getToolName(), Message, 156 &ToolArgv); 157 } 158 if (!Interpreter) { 159 InterpreterSel = RunLLC; 160 Interpreter = AbstractInterpreter::createLLC(getToolName(), Message, 161 GCCBinary, &ToolArgv, 162 &GCCToolArgv); 163 } 164 if (!Interpreter) { 165 InterpreterSel = RunLLI; 166 Interpreter = AbstractInterpreter::createLLI(getToolName(), Message, 167 &ToolArgv); 168 } 169 if (!Interpreter) { 170 InterpreterSel = AutoPick; 171 Message = "Sorry, I can't automatically select an interpreter!\n"; 172 } 173 break; 174 case RunLLI: 175 Interpreter = AbstractInterpreter::createLLI(getToolName(), Message, 176 &ToolArgv); 177 break; 178 case RunLLC: 179 case RunLLCIA: 180 case LLC_Safe: 181 Interpreter = AbstractInterpreter::createLLC(getToolName(), Message, 182 GCCBinary, &ToolArgv, 183 &GCCToolArgv, 184 InterpreterSel == RunLLCIA); 185 break; 186 case RunJIT: 187 Interpreter = AbstractInterpreter::createJIT(getToolName(), Message, 188 &ToolArgv); 189 break; 190 case CompileCustom: 191 Interpreter = 192 AbstractInterpreter::createCustomCompiler(Message, CustomCompileCommand); 193 break; 194 case Custom: 195 Interpreter = 196 AbstractInterpreter::createCustomExecutor(Message, CustomExecCommand); 197 break; 198 } 199 if (!Interpreter) 200 errs() << Message; 201 else // Display informational messages on stdout instead of stderr 202 outs() << Message; 203 204 std::string Path = SafeInterpreterPath; 205 if (Path.empty()) 206 Path = getToolName(); 207 std::vector<std::string> SafeToolArgs = SafeToolArgv; 208 switch (SafeInterpreterSel) { 209 case AutoPick: 210 // In "llc-safe" mode, default to using LLC as the "safe" backend. 211 if (!SafeInterpreter && 212 InterpreterSel == LLC_Safe) { 213 SafeInterpreterSel = RunLLC; 214 SafeToolArgs.push_back("--relocation-model=pic"); 215 SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message, 216 GCCBinary, 217 &SafeToolArgs, 218 &GCCToolArgv); 219 } 220 221 if (!SafeInterpreter && 222 InterpreterSel != RunLLC && 223 InterpreterSel != RunJIT) { 224 SafeInterpreterSel = RunLLC; 225 SafeToolArgs.push_back("--relocation-model=pic"); 226 SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message, 227 GCCBinary, 228 &SafeToolArgs, 229 &GCCToolArgv); 230 } 231 if (!SafeInterpreter) { 232 SafeInterpreterSel = AutoPick; 233 Message = "Sorry, I can't automatically select a safe interpreter!\n"; 234 } 235 break; 236 case RunLLC: 237 case RunLLCIA: 238 SafeToolArgs.push_back("--relocation-model=pic"); 239 SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message, 240 GCCBinary, &SafeToolArgs, 241 &GCCToolArgv, 242 SafeInterpreterSel == RunLLCIA); 243 break; 244 case Custom: 245 SafeInterpreter = 246 AbstractInterpreter::createCustomExecutor(Message, CustomExecCommand); 247 break; 248 default: 249 Message = "Sorry, this back-end is not supported by bugpoint as the " 250 "\"safe\" backend right now!\n"; 251 break; 252 } 253 if (!SafeInterpreter) { outs() << Message << "\nExiting.\n"; exit(1); } 254 255 gcc = GCC::create(Message, GCCBinary, &GCCToolArgv); 256 if (!gcc) { outs() << Message << "\nExiting.\n"; exit(1); } 257 258 // If there was an error creating the selected interpreter, quit with error. 259 return Interpreter == nullptr; 260 } 261 262 /// compileProgram - Try to compile the specified module, returning false and 263 /// setting Error if an error occurs. This is used for code generation 264 /// crash testing. 265 /// 266 void BugDriver::compileProgram(Module *M, std::string *Error) const { 267 // Emit the program to a bitcode file... 268 SmallString<128> BitcodeFile; 269 int BitcodeFD; 270 std::error_code EC = sys::fs::createUniqueFile( 271 OutputPrefix + "-test-program-%%%%%%%.bc", BitcodeFD, BitcodeFile); 272 if (EC) { 273 errs() << ToolName << ": Error making unique filename: " << EC.message() 274 << "\n"; 275 exit(1); 276 } 277 if (writeProgramToFile(BitcodeFile.str(), BitcodeFD, M)) { 278 errs() << ToolName << ": Error emitting bitcode to file '" << BitcodeFile 279 << "'!\n"; 280 exit(1); 281 } 282 283 // Remove the temporary bitcode file when we are done. 284 FileRemover BitcodeFileRemover(BitcodeFile.str(), !SaveTemps); 285 286 // Actually compile the program! 287 Interpreter->compileProgram(BitcodeFile.str(), Error, Timeout, MemoryLimit); 288 } 289 290 291 /// executeProgram - This method runs "Program", capturing the output of the 292 /// program to a file, returning the filename of the file. A recommended 293 /// filename may be optionally specified. 294 /// 295 std::string BugDriver::executeProgram(const Module *Program, 296 std::string OutputFile, 297 std::string BitcodeFile, 298 const std::string &SharedObj, 299 AbstractInterpreter *AI, 300 std::string *Error) const { 301 if (!AI) AI = Interpreter; 302 assert(AI && "Interpreter should have been created already!"); 303 bool CreatedBitcode = false; 304 if (BitcodeFile.empty()) { 305 // Emit the program to a bitcode file... 306 SmallString<128> UniqueFilename; 307 int UniqueFD; 308 std::error_code EC = sys::fs::createUniqueFile( 309 OutputPrefix + "-test-program-%%%%%%%.bc", UniqueFD, UniqueFilename); 310 if (EC) { 311 errs() << ToolName << ": Error making unique filename: " 312 << EC.message() << "!\n"; 313 exit(1); 314 } 315 BitcodeFile = UniqueFilename.str(); 316 317 if (writeProgramToFile(BitcodeFile, UniqueFD, Program)) { 318 errs() << ToolName << ": Error emitting bitcode to file '" 319 << BitcodeFile << "'!\n"; 320 exit(1); 321 } 322 CreatedBitcode = true; 323 } 324 325 // Remove the temporary bitcode file when we are done. 326 std::string BitcodePath(BitcodeFile); 327 FileRemover BitcodeFileRemover(BitcodePath, 328 CreatedBitcode && !SaveTemps); 329 330 if (OutputFile.empty()) OutputFile = OutputPrefix + "-execution-output-%%%%%%%"; 331 332 // Check to see if this is a valid output filename... 333 SmallString<128> UniqueFile; 334 std::error_code EC = sys::fs::createUniqueFile(OutputFile, UniqueFile); 335 if (EC) { 336 errs() << ToolName << ": Error making unique filename: " 337 << EC.message() << "\n"; 338 exit(1); 339 } 340 OutputFile = UniqueFile.str(); 341 342 // Figure out which shared objects to run, if any. 343 std::vector<std::string> SharedObjs(AdditionalSOs); 344 if (!SharedObj.empty()) 345 SharedObjs.push_back(SharedObj); 346 347 int RetVal = AI->ExecuteProgram(BitcodeFile, InputArgv, InputFile, OutputFile, 348 Error, AdditionalLinkerArgs, SharedObjs, 349 Timeout, MemoryLimit); 350 if (!Error->empty()) 351 return OutputFile; 352 353 if (RetVal == -1) { 354 errs() << "<timeout>"; 355 static bool FirstTimeout = true; 356 if (FirstTimeout) { 357 outs() << "\n" 358 "*** Program execution timed out! This mechanism is designed to handle\n" 359 " programs stuck in infinite loops gracefully. The -timeout option\n" 360 " can be used to change the timeout threshold or disable it completely\n" 361 " (with -timeout=0). This message is only displayed once.\n"; 362 FirstTimeout = false; 363 } 364 } 365 366 if (AppendProgramExitCode) { 367 std::ofstream outFile(OutputFile.c_str(), std::ios_base::app); 368 outFile << "exit " << RetVal << '\n'; 369 outFile.close(); 370 } 371 372 // Return the filename we captured the output to. 373 return OutputFile; 374 } 375 376 /// executeProgramSafely - Used to create reference output with the "safe" 377 /// backend, if reference output is not provided. 378 /// 379 std::string BugDriver::executeProgramSafely(const Module *Program, 380 std::string OutputFile, 381 std::string *Error) const { 382 return executeProgram(Program, OutputFile, "", "", SafeInterpreter, Error); 383 } 384 385 std::string BugDriver::compileSharedObject(const std::string &BitcodeFile, 386 std::string &Error) { 387 assert(Interpreter && "Interpreter should have been created already!"); 388 std::string OutputFile; 389 390 // Using the known-good backend. 391 GCC::FileType FT = SafeInterpreter->OutputCode(BitcodeFile, OutputFile, 392 Error); 393 if (!Error.empty()) 394 return ""; 395 396 std::string SharedObjectFile; 397 bool Failure = gcc->MakeSharedObject(OutputFile, FT, SharedObjectFile, 398 AdditionalLinkerArgs, Error); 399 if (!Error.empty()) 400 return ""; 401 if (Failure) 402 exit(1); 403 404 // Remove the intermediate C file 405 sys::fs::remove(OutputFile); 406 407 return SharedObjectFile; 408 } 409 410 /// createReferenceFile - calls compileProgram and then records the output 411 /// into ReferenceOutputFile. Returns true if reference file created, false 412 /// otherwise. Note: initializeExecutionEnvironment should be called BEFORE 413 /// this function. 414 /// 415 bool BugDriver::createReferenceFile(Module *M, const std::string &Filename) { 416 std::string Error; 417 compileProgram(Program, &Error); 418 if (!Error.empty()) 419 return false; 420 421 ReferenceOutputFile = executeProgramSafely(Program, Filename, &Error); 422 if (!Error.empty()) { 423 errs() << Error; 424 if (Interpreter != SafeInterpreter) { 425 errs() << "*** There is a bug running the \"safe\" backend. Either" 426 << " debug it (for example with the -run-jit bugpoint option," 427 << " if JIT is being used as the \"safe\" backend), or fix the" 428 << " error some other way.\n"; 429 } 430 return false; 431 } 432 outs() << "\nReference output is: " << ReferenceOutputFile << "\n\n"; 433 return true; 434 } 435 436 /// diffProgram - This method executes the specified module and diffs the 437 /// output against the file specified by ReferenceOutputFile. If the output 438 /// is different, 1 is returned. If there is a problem with the code 439 /// generator (e.g., llc crashes), this will set ErrMsg. 440 /// 441 bool BugDriver::diffProgram(const Module *Program, 442 const std::string &BitcodeFile, 443 const std::string &SharedObject, 444 bool RemoveBitcode, 445 std::string *ErrMsg) const { 446 // Execute the program, generating an output file... 447 std::string Output( 448 executeProgram(Program, "", BitcodeFile, SharedObject, nullptr, ErrMsg)); 449 if (!ErrMsg->empty()) 450 return false; 451 452 std::string Error; 453 bool FilesDifferent = false; 454 if (int Diff = DiffFilesWithTolerance(ReferenceOutputFile, 455 Output, 456 AbsTolerance, RelTolerance, &Error)) { 457 if (Diff == 2) { 458 errs() << "While diffing output: " << Error << '\n'; 459 exit(1); 460 } 461 FilesDifferent = true; 462 } 463 else { 464 // Remove the generated output if there are no differences. 465 sys::fs::remove(Output); 466 } 467 468 // Remove the bitcode file if we are supposed to. 469 if (RemoveBitcode) 470 sys::fs::remove(BitcodeFile); 471 return FilesDifferent; 472 } 473 474 bool BugDriver::isExecutingJIT() { 475 return InterpreterSel == RunJIT; 476 } 477 478
