OptimizerDriver.cpp revision 256281
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/Analysis/Verifier.h" 20#include "llvm/Bitcode/ReaderWriter.h" 21#include "llvm/IR/DataLayout.h" 22#include "llvm/IR/Module.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> 36using namespace llvm; 37 38namespace llvm { 39 extern cl::opt<std::string> OutputPrefix; 40} 41 42namespace { 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/// 51bool 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/// 72void 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 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 90 outs() << " -load " << PluginLoader::getPlugin(i); 91 } 92 outs() << " " << getPassesString(PassesToRun) << "\n"; 93} 94 95cl::opt<bool> SilencePasses("silence-passes", 96 cl::desc("Suppress output of running passes (both stdout and stderr)")); 97 98static cl::list<std::string> OptArgs("opt-args", cl::Positional, 99 cl::desc("<opt arguments>..."), 100 cl::ZeroOrMore, cl::PositionalEatsArgs); 101 102/// runPasses - Run the specified passes on Program, outputting a bitcode file 103/// and writing the filename into OutputFile if successful. If the 104/// optimizations fail for some reason (optimizer crashes), return true, 105/// otherwise return false. If DeleteOutput is set to true, the bitcode is 106/// deleted on success, and the filename string is undefined. This prints to 107/// outs() a single line message indicating whether compilation was successful 108/// or failed. 109/// 110bool BugDriver::runPasses(Module *Program, 111 const std::vector<std::string> &Passes, 112 std::string &OutputFilename, bool DeleteOutput, 113 bool Quiet, unsigned NumExtraArgs, 114 const char * const *ExtraArgs) const { 115 // setup the output file name 116 outs().flush(); 117 sys::Path uniqueFilename(OutputPrefix + "-output.bc"); 118 std::string ErrMsg; 119 if (uniqueFilename.makeUnique(true, &ErrMsg)) { 120 errs() << getToolName() << ": Error making unique filename: " 121 << ErrMsg << "\n"; 122 return(1); 123 } 124 OutputFilename = uniqueFilename.str(); 125 126 // set up the input file name 127 sys::Path inputFilename(OutputPrefix + "-input.bc"); 128 if (inputFilename.makeUnique(true, &ErrMsg)) { 129 errs() << getToolName() << ": Error making unique filename: " 130 << ErrMsg << "\n"; 131 return(1); 132 } 133 134 std::string ErrInfo; 135 tool_output_file InFile(inputFilename.c_str(), ErrInfo, 136 raw_fd_ostream::F_Binary); 137 138 139 if (!ErrInfo.empty()) { 140 errs() << "Error opening bitcode file: " << inputFilename.str() << "\n"; 141 return 1; 142 } 143 WriteBitcodeToFile(Program, InFile.os()); 144 InFile.os().close(); 145 if (InFile.os().has_error()) { 146 errs() << "Error writing bitcode file: " << inputFilename.str() << "\n"; 147 InFile.os().clear_error(); 148 return 1; 149 } 150 151 sys::Path tool = sys::Program::FindProgramByName("opt"); 152 if (tool.empty()) { 153 errs() << "Cannot find `opt' in PATH!\n"; 154 return 1; 155 } 156 157 // Ok, everything that could go wrong before running opt is done. 158 InFile.keep(); 159 160 // setup the child process' arguments 161 SmallVector<const char*, 8> Args; 162 std::string Opt = tool.str(); 163 if (UseValgrind) { 164 Args.push_back("valgrind"); 165 Args.push_back("--error-exitcode=1"); 166 Args.push_back("-q"); 167 Args.push_back(tool.c_str()); 168 } else 169 Args.push_back(Opt.c_str()); 170 171 Args.push_back("-o"); 172 Args.push_back(OutputFilename.c_str()); 173 for (unsigned i = 0, e = OptArgs.size(); i != e; ++i) 174 Args.push_back(OptArgs[i].c_str()); 175 std::vector<std::string> pass_args; 176 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 177 pass_args.push_back( std::string("-load")); 178 pass_args.push_back( PluginLoader::getPlugin(i)); 179 } 180 for (std::vector<std::string>::const_iterator I = Passes.begin(), 181 E = Passes.end(); I != E; ++I ) 182 pass_args.push_back( std::string("-") + (*I) ); 183 for (std::vector<std::string>::const_iterator I = pass_args.begin(), 184 E = pass_args.end(); I != E; ++I ) 185 Args.push_back(I->c_str()); 186 Args.push_back(inputFilename.c_str()); 187 for (unsigned i = 0; i < NumExtraArgs; ++i) 188 Args.push_back(*ExtraArgs); 189 Args.push_back(0); 190 191 DEBUG(errs() << "\nAbout to run:\t"; 192 for (unsigned i = 0, e = Args.size()-1; i != e; ++i) 193 errs() << " " << Args[i]; 194 errs() << "\n"; 195 ); 196 197 sys::Path prog; 198 if (UseValgrind) 199 prog = sys::Program::FindProgramByName("valgrind"); 200 else 201 prog = tool; 202 203 // Redirect stdout and stderr to nowhere if SilencePasses is given 204 sys::Path Nowhere; 205 const sys::Path *Redirects[3] = {0, &Nowhere, &Nowhere}; 206 207 int result = sys::Program::ExecuteAndWait(prog, Args.data(), 0, 208 (SilencePasses ? Redirects : 0), 209 Timeout, MemoryLimit, &ErrMsg); 210 211 // If we are supposed to delete the bitcode file or if the passes crashed, 212 // remove it now. This may fail if the file was never created, but that's ok. 213 if (DeleteOutput || result != 0) 214 sys::Path(OutputFilename).eraseFromDisk(); 215 216 // Remove the temporary input file as well 217 inputFilename.eraseFromDisk(); 218 219 if (!Quiet) { 220 if (result == 0) 221 outs() << "Success!\n"; 222 else if (result > 0) 223 outs() << "Exited with error code '" << result << "'\n"; 224 else if (result < 0) { 225 if (result == -1) 226 outs() << "Execute failed: " << ErrMsg << "\n"; 227 else 228 outs() << "Crashed: " << ErrMsg << "\n"; 229 } 230 if (result & 0x01000000) 231 outs() << "Dumped core\n"; 232 } 233 234 // Was the child successful? 235 return result != 0; 236} 237 238 239/// runPassesOn - Carefully run the specified set of pass on the specified 240/// module, returning the transformed module on success, or a null pointer on 241/// failure. 242Module *BugDriver::runPassesOn(Module *M, 243 const std::vector<std::string> &Passes, 244 bool AutoDebugCrashes, unsigned NumExtraArgs, 245 const char * const *ExtraArgs) { 246 std::string BitcodeResult; 247 if (runPasses(M, Passes, BitcodeResult, false/*delete*/, true/*quiet*/, 248 NumExtraArgs, ExtraArgs)) { 249 if (AutoDebugCrashes) { 250 errs() << " Error running this sequence of passes" 251 << " on the input program!\n"; 252 delete swapProgramIn(M); 253 EmitProgressBitcode(M, "pass-error", false); 254 exit(debugOptimizerCrash()); 255 } 256 return 0; 257 } 258 259 Module *Ret = ParseInputFile(BitcodeResult, Context); 260 if (Ret == 0) { 261 errs() << getToolName() << ": Error reading bitcode file '" 262 << BitcodeResult << "'!\n"; 263 exit(1); 264 } 265 sys::Path(BitcodeResult).eraseFromDisk(); // No longer need the file on disk 266 return Ret; 267} 268