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/Module.h" 20 #include "llvm/PassManager.h" 21 #include "llvm/Analysis/Verifier.h" 22 #include "llvm/Bitcode/ReaderWriter.h" 23 #include "llvm/Target/TargetData.h" 24 #include "llvm/Support/FileUtilities.h" 25 #include "llvm/Support/CommandLine.h" 26 #include "llvm/Support/SystemUtils.h" 27 #include "llvm/Support/Debug.h" 28 #include "llvm/Support/ToolOutputFile.h" 29 #include "llvm/Support/Path.h" 30 #include "llvm/Support/Program.h" 31 32 #define DONT_GET_PLUGIN_LOADER_OPTION 33 #include "llvm/Support/PluginLoader.h" 34 35 #include <fstream> 36 using namespace llvm; 37 38 namespace llvm { 39 extern cl::opt<std::string> OutputPrefix; 40 } 41 42 namespace { 43 // ChildOutput - This option captures the name of the child output file that 44 // is set up by the parent bugpoint process 45 cl::opt<std::string> ChildOutput("child-output", cl::ReallyHidden); 46 } 47 48 /// writeProgramToFile - This writes the current "Program" to the named bitcode 49 /// file. If an error occurs, true is returned. 50 /// 51 bool BugDriver::writeProgramToFile(const std::string &Filename, 52 const Module *M) const { 53 std::string ErrInfo; 54 tool_output_file Out(Filename.c_str(), ErrInfo, 55 raw_fd_ostream::F_Binary); 56 if (ErrInfo.empty()) { 57 WriteBitcodeToFile(M, Out.os()); 58 Out.os().close(); 59 if (!Out.os().has_error()) { 60 Out.keep(); 61 return false; 62 } 63 } 64 Out.os().clear_error(); 65 return true; 66 } 67 68 69 /// EmitProgressBitcode - This function is used to output the current Program 70 /// to a file named "bugpoint-ID.bc". 71 /// 72 void BugDriver::EmitProgressBitcode(const Module *M, 73 const std::string &ID, 74 bool NoFlyer) const { 75 // Output the input to the current pass to a bitcode file, emit a message 76 // telling the user how to reproduce it: opt -foo blah.bc 77 // 78 std::string Filename = OutputPrefix + "-" + ID + ".bc"; 79 if (writeProgramToFile(Filename, M)) { 80 errs() << "Error opening file '" << Filename << "' for writing!\n"; 81 return; 82 } 83 84 outs() << "Emitted bitcode to '" << Filename << "'\n"; 85 if (NoFlyer || PassesToRun.empty()) return; 86 outs() << "\n*** You can reproduce the problem with: "; 87 if (UseValgrind) outs() << "valgrind "; 88 outs() << "opt " << Filename << " "; 89 outs() << getPassesString(PassesToRun) << "\n"; 90 } 91 92 cl::opt<bool> SilencePasses("silence-passes", 93 cl::desc("Suppress output of running passes (both stdout and stderr)")); 94 95 static cl::list<std::string> OptArgs("opt-args", cl::Positional, 96 cl::desc("<opt arguments>..."), 97 cl::ZeroOrMore, cl::PositionalEatsArgs); 98 99 /// runPasses - Run the specified passes on Program, outputting a bitcode file 100 /// and writing the filename into OutputFile if successful. If the 101 /// optimizations fail for some reason (optimizer crashes), return true, 102 /// otherwise return false. If DeleteOutput is set to true, the bitcode is 103 /// deleted on success, and the filename string is undefined. This prints to 104 /// outs() a single line message indicating whether compilation was successful 105 /// or failed. 106 /// 107 bool BugDriver::runPasses(Module *Program, 108 const std::vector<std::string> &Passes, 109 std::string &OutputFilename, bool DeleteOutput, 110 bool Quiet, unsigned NumExtraArgs, 111 const char * const *ExtraArgs) const { 112 // setup the output file name 113 outs().flush(); 114 sys::Path uniqueFilename(OutputPrefix + "-output.bc"); 115 std::string ErrMsg; 116 if (uniqueFilename.makeUnique(true, &ErrMsg)) { 117 errs() << getToolName() << ": Error making unique filename: " 118 << ErrMsg << "\n"; 119 return(1); 120 } 121 OutputFilename = uniqueFilename.str(); 122 123 // set up the input file name 124 sys::Path inputFilename(OutputPrefix + "-input.bc"); 125 if (inputFilename.makeUnique(true, &ErrMsg)) { 126 errs() << getToolName() << ": Error making unique filename: " 127 << ErrMsg << "\n"; 128 return(1); 129 } 130 131 std::string ErrInfo; 132 tool_output_file InFile(inputFilename.c_str(), ErrInfo, 133 raw_fd_ostream::F_Binary); 134 135 136 if (!ErrInfo.empty()) { 137 errs() << "Error opening bitcode file: " << inputFilename.str() << "\n"; 138 return 1; 139 } 140 WriteBitcodeToFile(Program, InFile.os()); 141 InFile.os().close(); 142 if (InFile.os().has_error()) { 143 errs() << "Error writing bitcode file: " << inputFilename.str() << "\n"; 144 InFile.os().clear_error(); 145 return 1; 146 } 147 148 sys::Path tool = PrependMainExecutablePath("opt", getToolName(), 149 (void*)"opt"); 150 if (tool.empty()) { 151 errs() << "Cannot find `opt' in executable directory!\n"; 152 return 1; 153 } 154 155 // Ok, everything that could go wrong before running opt is done. 156 InFile.keep(); 157 158 // setup the child process' arguments 159 SmallVector<const char*, 8> Args; 160 std::string Opt = tool.str(); 161 if (UseValgrind) { 162 Args.push_back("valgrind"); 163 Args.push_back("--error-exitcode=1"); 164 Args.push_back("-q"); 165 Args.push_back(tool.c_str()); 166 } else 167 Args.push_back(Opt.c_str()); 168 169 Args.push_back("-o"); 170 Args.push_back(OutputFilename.c_str()); 171 for (unsigned i = 0, e = OptArgs.size(); i != e; ++i) 172 Args.push_back(OptArgs[i].c_str()); 173 std::vector<std::string> pass_args; 174 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 175 pass_args.push_back( std::string("-load")); 176 pass_args.push_back( PluginLoader::getPlugin(i)); 177 } 178 for (std::vector<std::string>::const_iterator I = Passes.begin(), 179 E = Passes.end(); I != E; ++I ) 180 pass_args.push_back( std::string("-") + (*I) ); 181 for (std::vector<std::string>::const_iterator I = pass_args.begin(), 182 E = pass_args.end(); I != E; ++I ) 183 Args.push_back(I->c_str()); 184 Args.push_back(inputFilename.c_str()); 185 for (unsigned i = 0; i < NumExtraArgs; ++i) 186 Args.push_back(*ExtraArgs); 187 Args.push_back(0); 188 189 DEBUG(errs() << "\nAbout to run:\t"; 190 for (unsigned i = 0, e = Args.size()-1; i != e; ++i) 191 errs() << " " << Args[i]; 192 errs() << "\n"; 193 ); 194 195 sys::Path prog; 196 if (UseValgrind) 197 prog = sys::Program::FindProgramByName("valgrind"); 198 else 199 prog = tool; 200 201 // Redirect stdout and stderr to nowhere if SilencePasses is given 202 sys::Path Nowhere; 203 const sys::Path *Redirects[3] = {0, &Nowhere, &Nowhere}; 204 205 int result = sys::Program::ExecuteAndWait(prog, Args.data(), 0, 206 (SilencePasses ? Redirects : 0), 207 Timeout, MemoryLimit, &ErrMsg); 208 209 // If we are supposed to delete the bitcode file or if the passes crashed, 210 // remove it now. This may fail if the file was never created, but that's ok. 211 if (DeleteOutput || result != 0) 212 sys::Path(OutputFilename).eraseFromDisk(); 213 214 // Remove the temporary input file as well 215 inputFilename.eraseFromDisk(); 216 217 if (!Quiet) { 218 if (result == 0) 219 outs() << "Success!\n"; 220 else if (result > 0) 221 outs() << "Exited with error code '" << result << "'\n"; 222 else if (result < 0) { 223 if (result == -1) 224 outs() << "Execute failed: " << ErrMsg << "\n"; 225 else 226 outs() << "Crashed: " << ErrMsg << "\n"; 227 } 228 if (result & 0x01000000) 229 outs() << "Dumped core\n"; 230 } 231 232 // Was the child successful? 233 return result != 0; 234 } 235 236 237 /// runPassesOn - Carefully run the specified set of pass on the specified 238 /// module, returning the transformed module on success, or a null pointer on 239 /// failure. 240 Module *BugDriver::runPassesOn(Module *M, 241 const std::vector<std::string> &Passes, 242 bool AutoDebugCrashes, unsigned NumExtraArgs, 243 const char * const *ExtraArgs) { 244 std::string BitcodeResult; 245 if (runPasses(M, Passes, BitcodeResult, false/*delete*/, true/*quiet*/, 246 NumExtraArgs, ExtraArgs)) { 247 if (AutoDebugCrashes) { 248 errs() << " Error running this sequence of passes" 249 << " on the input program!\n"; 250 delete swapProgramIn(M); 251 EmitProgressBitcode(M, "pass-error", false); 252 exit(debugOptimizerCrash()); 253 } 254 return 0; 255 } 256 257 Module *Ret = ParseInputFile(BitcodeResult, Context); 258 if (Ret == 0) { 259 errs() << getToolName() << ": Error reading bitcode file '" 260 << BitcodeResult << "'!\n"; 261 exit(1); 262 } 263 sys::Path(BitcodeResult).eraseFromDisk(); // No longer need the file on disk 264 return Ret; 265 } 266