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/Module.h" 22 #include "llvm/IR/Verifier.h" 23 #include "llvm/PassManager.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 namespace { 46 // ChildOutput - This option captures the name of the child output file that 47 // is set up by the parent bugpoint process 48 cl::opt<std::string> ChildOutput("child-output", cl::ReallyHidden); 49 cl::opt<std::string> OptCmd("opt-command", cl::init(""), 50 cl::desc("Path to opt. (default: search path " 51 "for 'opt'.)")); 52 } 53 54 /// writeProgramToFile - This writes the current "Program" to the named bitcode 55 /// file. If an error occurs, true is returned. 56 /// 57 static bool writeProgramToFileAux(tool_output_file &Out, const Module *M) { 58 WriteBitcodeToFile(M, Out.os()); 59 Out.os().close(); 60 if (!Out.os().has_error()) { 61 Out.keep(); 62 return false; 63 } 64 return true; 65 } 66 67 bool BugDriver::writeProgramToFile(const std::string &Filename, int FD, 68 const Module *M) const { 69 tool_output_file Out(Filename.c_str(), FD); 70 return writeProgramToFileAux(Out, M); 71 } 72 73 bool BugDriver::writeProgramToFile(const std::string &Filename, 74 const Module *M) const { 75 std::string ErrInfo; 76 tool_output_file Out(Filename.c_str(), ErrInfo, sys::fs::F_None); 77 if (ErrInfo.empty()) 78 return writeProgramToFileAux(Out, M); 79 return true; 80 } 81 82 83 /// EmitProgressBitcode - This function is used to output the current Program 84 /// to a file named "bugpoint-ID.bc". 85 /// 86 void BugDriver::EmitProgressBitcode(const Module *M, 87 const std::string &ID, 88 bool NoFlyer) const { 89 // Output the input to the current pass to a bitcode file, emit a message 90 // telling the user how to reproduce it: opt -foo blah.bc 91 // 92 std::string Filename = OutputPrefix + "-" + ID + ".bc"; 93 if (writeProgramToFile(Filename, M)) { 94 errs() << "Error opening file '" << Filename << "' for writing!\n"; 95 return; 96 } 97 98 outs() << "Emitted bitcode to '" << Filename << "'\n"; 99 if (NoFlyer || PassesToRun.empty()) return; 100 outs() << "\n*** You can reproduce the problem with: "; 101 if (UseValgrind) outs() << "valgrind "; 102 outs() << "opt " << Filename; 103 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 104 outs() << " -load " << PluginLoader::getPlugin(i); 105 } 106 outs() << " " << getPassesString(PassesToRun) << "\n"; 107 } 108 109 cl::opt<bool> SilencePasses("silence-passes", 110 cl::desc("Suppress output of running passes (both stdout and stderr)")); 111 112 static cl::list<std::string> OptArgs("opt-args", cl::Positional, 113 cl::desc("<opt arguments>..."), 114 cl::ZeroOrMore, cl::PositionalEatsArgs); 115 116 /// runPasses - Run the specified passes on Program, outputting a bitcode file 117 /// and writing the filename into OutputFile if successful. If the 118 /// optimizations fail for some reason (optimizer crashes), return true, 119 /// otherwise return false. If DeleteOutput is set to true, the bitcode is 120 /// deleted on success, and the filename string is undefined. This prints to 121 /// outs() a single line message indicating whether compilation was successful 122 /// or failed. 123 /// 124 bool BugDriver::runPasses(Module *Program, 125 const std::vector<std::string> &Passes, 126 std::string &OutputFilename, bool DeleteOutput, 127 bool Quiet, unsigned NumExtraArgs, 128 const char * const *ExtraArgs) const { 129 // setup the output file name 130 outs().flush(); 131 SmallString<128> UniqueFilename; 132 std::error_code EC = sys::fs::createUniqueFile( 133 OutputPrefix + "-output-%%%%%%%.bc", UniqueFilename); 134 if (EC) { 135 errs() << getToolName() << ": Error making unique filename: " 136 << EC.message() << "\n"; 137 return 1; 138 } 139 OutputFilename = UniqueFilename.str(); 140 141 // set up the input file name 142 SmallString<128> InputFilename; 143 int InputFD; 144 EC = sys::fs::createUniqueFile(OutputPrefix + "-input-%%%%%%%.bc", InputFD, 145 InputFilename); 146 if (EC) { 147 errs() << getToolName() << ": Error making unique filename: " 148 << EC.message() << "\n"; 149 return 1; 150 } 151 152 tool_output_file InFile(InputFilename.c_str(), InputFD); 153 154 WriteBitcodeToFile(Program, InFile.os()); 155 InFile.os().close(); 156 if (InFile.os().has_error()) { 157 errs() << "Error writing bitcode file: " << InputFilename << "\n"; 158 InFile.os().clear_error(); 159 return 1; 160 } 161 162 std::string tool = OptCmd.empty()? sys::FindProgramByName("opt") : OptCmd; 163 if (tool.empty()) { 164 errs() << "Cannot find `opt' in PATH!\n"; 165 return 1; 166 } 167 168 // Ok, everything that could go wrong before running opt is done. 169 InFile.keep(); 170 171 // setup the child process' arguments 172 SmallVector<const char*, 8> Args; 173 if (UseValgrind) { 174 Args.push_back("valgrind"); 175 Args.push_back("--error-exitcode=1"); 176 Args.push_back("-q"); 177 Args.push_back(tool.c_str()); 178 } else 179 Args.push_back(tool.c_str()); 180 181 Args.push_back("-o"); 182 Args.push_back(OutputFilename.c_str()); 183 for (unsigned i = 0, e = OptArgs.size(); i != e; ++i) 184 Args.push_back(OptArgs[i].c_str()); 185 std::vector<std::string> pass_args; 186 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 187 pass_args.push_back( std::string("-load")); 188 pass_args.push_back( PluginLoader::getPlugin(i)); 189 } 190 for (std::vector<std::string>::const_iterator I = Passes.begin(), 191 E = Passes.end(); I != E; ++I ) 192 pass_args.push_back( std::string("-") + (*I) ); 193 for (std::vector<std::string>::const_iterator I = pass_args.begin(), 194 E = pass_args.end(); I != E; ++I ) 195 Args.push_back(I->c_str()); 196 Args.push_back(InputFilename.c_str()); 197 for (unsigned i = 0; i < NumExtraArgs; ++i) 198 Args.push_back(*ExtraArgs); 199 Args.push_back(nullptr); 200 201 DEBUG(errs() << "\nAbout to run:\t"; 202 for (unsigned i = 0, e = Args.size()-1; i != e; ++i) 203 errs() << " " << Args[i]; 204 errs() << "\n"; 205 ); 206 207 std::string Prog; 208 if (UseValgrind) 209 Prog = sys::FindProgramByName("valgrind"); 210 else 211 Prog = tool; 212 213 // Redirect stdout and stderr to nowhere if SilencePasses is given 214 StringRef Nowhere; 215 const StringRef *Redirects[3] = {nullptr, &Nowhere, &Nowhere}; 216 217 std::string ErrMsg; 218 int result = sys::ExecuteAndWait(Prog, Args.data(), nullptr, 219 (SilencePasses ? Redirects : nullptr), 220 Timeout, MemoryLimit, &ErrMsg); 221 222 // If we are supposed to delete the bitcode file or if the passes crashed, 223 // remove it now. This may fail if the file was never created, but that's ok. 224 if (DeleteOutput || result != 0) 225 sys::fs::remove(OutputFilename); 226 227 // Remove the temporary input file as well 228 sys::fs::remove(InputFilename.c_str()); 229 230 if (!Quiet) { 231 if (result == 0) 232 outs() << "Success!\n"; 233 else if (result > 0) 234 outs() << "Exited with error code '" << result << "'\n"; 235 else if (result < 0) { 236 if (result == -1) 237 outs() << "Execute failed: " << ErrMsg << "\n"; 238 else 239 outs() << "Crashed: " << ErrMsg << "\n"; 240 } 241 if (result & 0x01000000) 242 outs() << "Dumped core\n"; 243 } 244 245 // Was the child successful? 246 return result != 0; 247 } 248 249 250 /// runPassesOn - Carefully run the specified set of pass on the specified 251 /// module, returning the transformed module on success, or a null pointer on 252 /// failure. 253 Module *BugDriver::runPassesOn(Module *M, 254 const std::vector<std::string> &Passes, 255 bool AutoDebugCrashes, unsigned NumExtraArgs, 256 const char * const *ExtraArgs) { 257 std::string BitcodeResult; 258 if (runPasses(M, Passes, BitcodeResult, false/*delete*/, true/*quiet*/, 259 NumExtraArgs, ExtraArgs)) { 260 if (AutoDebugCrashes) { 261 errs() << " Error running this sequence of passes" 262 << " on the input program!\n"; 263 delete swapProgramIn(M); 264 EmitProgressBitcode(M, "pass-error", false); 265 exit(debugOptimizerCrash()); 266 } 267 return nullptr; 268 } 269 270 Module *Ret = ParseInputFile(BitcodeResult, Context); 271 if (!Ret) { 272 errs() << getToolName() << ": Error reading bitcode file '" 273 << BitcodeResult << "'!\n"; 274 exit(1); 275 } 276 sys::fs::remove(BitcodeResult); 277 return Ret; 278 } 279