1 //===- OptimizerDriver.cpp - Allow BugPoint to run passes safely ----------===// 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 defines an interface that allows bugpoint to run various passes 11 // without the threat of a buggy pass corrupting bugpoint (of course, bugpoint 12 // may have its own bugs, but that's another story...). It achieves this by 13 // forking a copy of itself and having the child process do the optimizations. 14 // If this client dies, we can always fork a new one. :) 15 // 16 //===----------------------------------------------------------------------===// 17 18 #include "BugDriver.h" 19 #include "llvm/Bitcode/ReaderWriter.h" 20 #include "llvm/IR/DataLayout.h" 21 #include "llvm/IR/LegacyPassManager.h" 22 #include "llvm/IR/Module.h" 23 #include "llvm/IR/Verifier.h" 24 #include "llvm/Support/CommandLine.h" 25 #include "llvm/Support/Debug.h" 26 #include "llvm/Support/FileUtilities.h" 27 #include "llvm/Support/Path.h" 28 #include "llvm/Support/Program.h" 29 #include "llvm/Support/SystemUtils.h" 30 #include "llvm/Support/ToolOutputFile.h" 31 32 #define DONT_GET_PLUGIN_LOADER_OPTION 33 #include "llvm/Support/PluginLoader.h" 34 35 #include <fstream> 36 37 using namespace llvm; 38 39 #define DEBUG_TYPE "bugpoint" 40 41 namespace llvm { 42 extern cl::opt<std::string> OutputPrefix; 43 } 44 45 static cl::opt<bool> PreserveBitcodeUseListOrder( 46 "preserve-bc-uselistorder", 47 cl::desc("Preserve use-list order when writing LLVM bitcode."), 48 cl::init(true), cl::Hidden); 49 50 namespace { 51 // ChildOutput - This option captures the name of the child output file that 52 // is set up by the parent bugpoint process 53 cl::opt<std::string> ChildOutput("child-output", cl::ReallyHidden); 54 cl::opt<std::string> OptCmd("opt-command", cl::init(""), 55 cl::desc("Path to opt. (default: search path " 56 "for 'opt'.)")); 57 } 58 59 /// writeProgramToFile - This writes the current "Program" to the named bitcode 60 /// file. If an error occurs, true is returned. 61 /// 62 static bool writeProgramToFileAux(tool_output_file &Out, const Module *M) { 63 WriteBitcodeToFile(M, Out.os(), PreserveBitcodeUseListOrder); 64 Out.os().close(); 65 if (!Out.os().has_error()) { 66 Out.keep(); 67 return false; 68 } 69 return true; 70 } 71 72 bool BugDriver::writeProgramToFile(const std::string &Filename, int FD, 73 const Module *M) const { 74 tool_output_file Out(Filename, FD); 75 return writeProgramToFileAux(Out, M); 76 } 77 78 bool BugDriver::writeProgramToFile(const std::string &Filename, 79 const Module *M) const { 80 std::error_code EC; 81 tool_output_file Out(Filename, EC, sys::fs::F_None); 82 if (!EC) 83 return writeProgramToFileAux(Out, M); 84 return true; 85 } 86 87 88 /// EmitProgressBitcode - This function is used to output the current Program 89 /// to a file named "bugpoint-ID.bc". 90 /// 91 void BugDriver::EmitProgressBitcode(const Module *M, 92 const std::string &ID, 93 bool NoFlyer) const { 94 // Output the input to the current pass to a bitcode file, emit a message 95 // telling the user how to reproduce it: opt -foo blah.bc 96 // 97 std::string Filename = OutputPrefix + "-" + ID + ".bc"; 98 if (writeProgramToFile(Filename, M)) { 99 errs() << "Error opening file '" << Filename << "' for writing!\n"; 100 return; 101 } 102 103 outs() << "Emitted bitcode to '" << Filename << "'\n"; 104 if (NoFlyer || PassesToRun.empty()) return; 105 outs() << "\n*** You can reproduce the problem with: "; 106 if (UseValgrind) outs() << "valgrind "; 107 outs() << "opt " << Filename; 108 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 109 outs() << " -load " << PluginLoader::getPlugin(i); 110 } 111 outs() << " " << getPassesString(PassesToRun) << "\n"; 112 } 113 114 cl::opt<bool> SilencePasses("silence-passes", 115 cl::desc("Suppress output of running passes (both stdout and stderr)")); 116 117 static cl::list<std::string> OptArgs("opt-args", cl::Positional, 118 cl::desc("<opt arguments>..."), 119 cl::ZeroOrMore, cl::PositionalEatsArgs); 120 121 /// runPasses - Run the specified passes on Program, outputting a bitcode file 122 /// and writing the filename into OutputFile if successful. If the 123 /// optimizations fail for some reason (optimizer crashes), return true, 124 /// otherwise return false. If DeleteOutput is set to true, the bitcode is 125 /// deleted on success, and the filename string is undefined. This prints to 126 /// outs() a single line message indicating whether compilation was successful 127 /// or failed. 128 /// 129 bool BugDriver::runPasses(Module *Program, 130 const std::vector<std::string> &Passes, 131 std::string &OutputFilename, bool DeleteOutput, 132 bool Quiet, unsigned NumExtraArgs, 133 const char * const *ExtraArgs) const { 134 // setup the output file name 135 outs().flush(); 136 SmallString<128> UniqueFilename; 137 std::error_code EC = sys::fs::createUniqueFile( 138 OutputPrefix + "-output-%%%%%%%.bc", UniqueFilename); 139 if (EC) { 140 errs() << getToolName() << ": Error making unique filename: " 141 << EC.message() << "\n"; 142 return 1; 143 } 144 OutputFilename = UniqueFilename.str(); 145 146 // set up the input file name 147 SmallString<128> InputFilename; 148 int InputFD; 149 EC = sys::fs::createUniqueFile(OutputPrefix + "-input-%%%%%%%.bc", InputFD, 150 InputFilename); 151 if (EC) { 152 errs() << getToolName() << ": Error making unique filename: " 153 << EC.message() << "\n"; 154 return 1; 155 } 156 157 tool_output_file InFile(InputFilename, InputFD); 158 159 WriteBitcodeToFile(Program, InFile.os(), PreserveBitcodeUseListOrder); 160 InFile.os().close(); 161 if (InFile.os().has_error()) { 162 errs() << "Error writing bitcode file: " << InputFilename << "\n"; 163 InFile.os().clear_error(); 164 return 1; 165 } 166 167 std::string tool = OptCmd; 168 if (OptCmd.empty()) { 169 if (ErrorOr<std::string> Path = sys::findProgramByName("opt")) 170 tool = *Path; 171 else 172 errs() << Path.getError().message() << "\n"; 173 } 174 if (tool.empty()) { 175 errs() << "Cannot find `opt' in PATH!\n"; 176 return 1; 177 } 178 179 std::string Prog; 180 if (UseValgrind) { 181 if (ErrorOr<std::string> Path = sys::findProgramByName("valgrind")) 182 Prog = *Path; 183 else 184 errs() << Path.getError().message() << "\n"; 185 } else 186 Prog = tool; 187 if (Prog.empty()) { 188 errs() << "Cannot find `valgrind' in PATH!\n"; 189 return 1; 190 } 191 192 // Ok, everything that could go wrong before running opt is done. 193 InFile.keep(); 194 195 // setup the child process' arguments 196 SmallVector<const char*, 8> Args; 197 if (UseValgrind) { 198 Args.push_back("valgrind"); 199 Args.push_back("--error-exitcode=1"); 200 Args.push_back("-q"); 201 Args.push_back(tool.c_str()); 202 } else 203 Args.push_back(tool.c_str()); 204 205 Args.push_back("-o"); 206 Args.push_back(OutputFilename.c_str()); 207 for (unsigned i = 0, e = OptArgs.size(); i != e; ++i) 208 Args.push_back(OptArgs[i].c_str()); 209 std::vector<std::string> pass_args; 210 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 211 pass_args.push_back( std::string("-load")); 212 pass_args.push_back( PluginLoader::getPlugin(i)); 213 } 214 for (std::vector<std::string>::const_iterator I = Passes.begin(), 215 E = Passes.end(); I != E; ++I ) 216 pass_args.push_back( std::string("-") + (*I) ); 217 for (std::vector<std::string>::const_iterator I = pass_args.begin(), 218 E = pass_args.end(); I != E; ++I ) 219 Args.push_back(I->c_str()); 220 Args.push_back(InputFilename.c_str()); 221 for (unsigned i = 0; i < NumExtraArgs; ++i) 222 Args.push_back(*ExtraArgs); 223 Args.push_back(nullptr); 224 225 DEBUG(errs() << "\nAbout to run:\t"; 226 for (unsigned i = 0, e = Args.size()-1; i != e; ++i) 227 errs() << " " << Args[i]; 228 errs() << "\n"; 229 ); 230 231 // Redirect stdout and stderr to nowhere if SilencePasses is given 232 StringRef Nowhere; 233 const StringRef *Redirects[3] = {nullptr, &Nowhere, &Nowhere}; 234 235 std::string ErrMsg; 236 int result = sys::ExecuteAndWait(Prog, Args.data(), nullptr, 237 (SilencePasses ? Redirects : nullptr), 238 Timeout, MemoryLimit, &ErrMsg); 239 240 // If we are supposed to delete the bitcode file or if the passes crashed, 241 // remove it now. This may fail if the file was never created, but that's ok. 242 if (DeleteOutput || result != 0) 243 sys::fs::remove(OutputFilename); 244 245 // Remove the temporary input file as well 246 sys::fs::remove(InputFilename.c_str()); 247 248 if (!Quiet) { 249 if (result == 0) 250 outs() << "Success!\n"; 251 else if (result > 0) 252 outs() << "Exited with error code '" << result << "'\n"; 253 else if (result < 0) { 254 if (result == -1) 255 outs() << "Execute failed: " << ErrMsg << "\n"; 256 else 257 outs() << "Crashed: " << ErrMsg << "\n"; 258 } 259 if (result & 0x01000000) 260 outs() << "Dumped core\n"; 261 } 262 263 // Was the child successful? 264 return result != 0; 265 } 266 267 268 std::unique_ptr<Module> 269 BugDriver::runPassesOn(Module *M, const std::vector<std::string> &Passes, 270 bool AutoDebugCrashes, unsigned NumExtraArgs, 271 const char *const *ExtraArgs) { 272 std::string BitcodeResult; 273 if (runPasses(M, Passes, BitcodeResult, false/*delete*/, true/*quiet*/, 274 NumExtraArgs, ExtraArgs)) { 275 if (AutoDebugCrashes) { 276 errs() << " Error running this sequence of passes" 277 << " on the input program!\n"; 278 delete swapProgramIn(M); 279 EmitProgressBitcode(M, "pass-error", false); 280 exit(debugOptimizerCrash()); 281 } 282 return nullptr; 283 } 284 285 std::unique_ptr<Module> Ret = parseInputFile(BitcodeResult, Context); 286 if (!Ret) { 287 errs() << getToolName() << ": Error reading bitcode file '" 288 << BitcodeResult << "'!\n"; 289 exit(1); 290 } 291 sys::fs::remove(BitcodeResult); 292 return Ret; 293 } 294
