OptimizerDriver.cpp revision 198090
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// Note: as a short term hack, the old Unix-specific code and platform- 19// independent code co-exist via conditional compilation until it is verified 20// that the new code works correctly on Unix. 21 22#include "BugDriver.h" 23#include "llvm/Module.h" 24#include "llvm/PassManager.h" 25#include "llvm/Analysis/Verifier.h" 26#include "llvm/Bitcode/ReaderWriter.h" 27#include "llvm/Target/TargetData.h" 28#include "llvm/Support/FileUtilities.h" 29#include "llvm/Support/CommandLine.h" 30#include "llvm/Support/raw_ostream.h" 31#include "llvm/System/Path.h" 32#include "llvm/System/Program.h" 33 34#define DONT_GET_PLUGIN_LOADER_OPTION 35#include "llvm/Support/PluginLoader.h" 36 37#include <fstream> 38using namespace llvm; 39 40namespace llvm { 41 extern cl::opt<std::string> OutputPrefix; 42} 43 44namespace { 45 // ChildOutput - This option captures the name of the child output file that 46 // is set up by the parent bugpoint process 47 cl::opt<std::string> ChildOutput("child-output", cl::ReallyHidden); 48 cl::opt<bool> UseValgrind("enable-valgrind", 49 cl::desc("Run optimizations through valgrind")); 50} 51 52/// writeProgramToFile - This writes the current "Program" to the named bitcode 53/// file. If an error occurs, true is returned. 54/// 55bool BugDriver::writeProgramToFile(const std::string &Filename, 56 Module *M) const { 57 std::string ErrInfo; 58 raw_fd_ostream Out(Filename.c_str(), ErrInfo, 59 raw_fd_ostream::F_Binary); 60 if (!ErrInfo.empty()) return true; 61 62 WriteBitcodeToFile(M ? M : Program, Out); 63 return false; 64} 65 66 67/// EmitProgressBitcode - This function is used to output the current Program 68/// to a file named "bugpoint-ID.bc". 69/// 70void BugDriver::EmitProgressBitcode(const std::string &ID, bool NoFlyer) { 71 // Output the input to the current pass to a bitcode file, emit a message 72 // telling the user how to reproduce it: opt -foo blah.bc 73 // 74 std::string Filename = OutputPrefix + "-" + ID + ".bc"; 75 if (writeProgramToFile(Filename)) { 76 errs() << "Error opening file '" << Filename << "' for writing!\n"; 77 return; 78 } 79 80 outs() << "Emitted bitcode to '" << Filename << "'\n"; 81 if (NoFlyer || PassesToRun.empty()) return; 82 outs() << "\n*** You can reproduce the problem with: "; 83 if (UseValgrind) outs() << "valgrind "; 84 outs() << "opt " << Filename << " "; 85 outs() << getPassesString(PassesToRun) << "\n"; 86} 87 88int BugDriver::runPassesAsChild(const std::vector<const PassInfo*> &Passes) { 89 std::string ErrInfo; 90 raw_fd_ostream OutFile(ChildOutput.c_str(), ErrInfo, 91 raw_fd_ostream::F_Binary); 92 if (!ErrInfo.empty()) { 93 errs() << "Error opening bitcode file: " << ChildOutput << "\n"; 94 return 1; 95 } 96 97 PassManager PM; 98 // Make sure that the appropriate target data is always used... 99 PM.add(new TargetData(Program)); 100 101 for (unsigned i = 0, e = Passes.size(); i != e; ++i) { 102 if (Passes[i]->getNormalCtor()) 103 PM.add(Passes[i]->getNormalCtor()()); 104 else 105 errs() << "Cannot create pass yet: " << Passes[i]->getPassName() << "\n"; 106 } 107 // Check that the module is well formed on completion of optimization 108 PM.add(createVerifierPass()); 109 110 // Write bitcode out to disk as the last step... 111 PM.add(createBitcodeWriterPass(OutFile)); 112 113 // Run all queued passes. 114 PM.run(*Program); 115 116 return 0; 117} 118 119cl::opt<bool> SilencePasses("silence-passes", cl::desc("Suppress output of running passes (both stdout and stderr)")); 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/// 129bool BugDriver::runPasses(const std::vector<const PassInfo*> &Passes, 130 std::string &OutputFilename, bool DeleteOutput, 131 bool Quiet, unsigned NumExtraArgs, 132 const char * const *ExtraArgs) const { 133 // setup the output file name 134 outs().flush(); 135 sys::Path uniqueFilename(OutputPrefix + "-output.bc"); 136 std::string ErrMsg; 137 if (uniqueFilename.makeUnique(true, &ErrMsg)) { 138 errs() << getToolName() << ": Error making unique filename: " 139 << ErrMsg << "\n"; 140 return(1); 141 } 142 OutputFilename = uniqueFilename.str(); 143 144 // set up the input file name 145 sys::Path inputFilename(OutputPrefix + "-input.bc"); 146 if (inputFilename.makeUnique(true, &ErrMsg)) { 147 errs() << getToolName() << ": Error making unique filename: " 148 << ErrMsg << "\n"; 149 return(1); 150 } 151 152 std::string ErrInfo; 153 raw_fd_ostream InFile(inputFilename.c_str(), ErrInfo, 154 raw_fd_ostream::F_Binary); 155 156 157 if (!ErrInfo.empty()) { 158 errs() << "Error opening bitcode file: " << inputFilename.str() << "\n"; 159 return 1; 160 } 161 WriteBitcodeToFile(Program, InFile); 162 InFile.close(); 163 164 // setup the child process' arguments 165 SmallVector<const char*, 8> Args; 166 sys::Path tool = sys::Program::FindProgramByName(ToolName); 167 if (UseValgrind) { 168 Args.push_back("valgrind"); 169 Args.push_back("--error-exitcode=1"); 170 Args.push_back("-q"); 171 Args.push_back(tool.c_str()); 172 } else 173 Args.push_back(ToolName); 174 175 Args.push_back("-as-child"); 176 Args.push_back("-child-output"); 177 Args.push_back(OutputFilename.c_str()); 178 std::vector<std::string> pass_args; 179 for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) { 180 pass_args.push_back( std::string("-load")); 181 pass_args.push_back( PluginLoader::getPlugin(i)); 182 } 183 for (std::vector<const PassInfo*>::const_iterator I = Passes.begin(), 184 E = Passes.end(); I != E; ++I ) 185 pass_args.push_back( std::string("-") + (*I)->getPassArgument() ); 186 for (std::vector<std::string>::const_iterator I = pass_args.begin(), 187 E = pass_args.end(); I != E; ++I ) 188 Args.push_back(I->c_str()); 189 Args.push_back(inputFilename.c_str()); 190 for (unsigned i = 0; i < NumExtraArgs; ++i) 191 Args.push_back(*ExtraArgs); 192 Args.push_back(0); 193 194 sys::Path prog; 195 if (UseValgrind) 196 prog = sys::Program::FindProgramByName("valgrind"); 197 else 198 prog = tool; 199 200 // Redirect stdout and stderr to nowhere if SilencePasses is given 201 sys::Path Nowhere; 202 const sys::Path *Redirects[3] = {0, &Nowhere, &Nowhere}; 203 204 int result = sys::Program::ExecuteAndWait(prog, Args.data(), 0, 205 (SilencePasses ? Redirects : 0), 206 Timeout, MemoryLimit, &ErrMsg); 207 208 // If we are supposed to delete the bitcode file or if the passes crashed, 209 // remove it now. This may fail if the file was never created, but that's ok. 210 if (DeleteOutput || result != 0) 211 sys::Path(OutputFilename).eraseFromDisk(); 212 213 // Remove the temporary input file as well 214 inputFilename.eraseFromDisk(); 215 216 if (!Quiet) { 217 if (result == 0) 218 outs() << "Success!\n"; 219 else if (result > 0) 220 outs() << "Exited with error code '" << result << "'\n"; 221 else if (result < 0) { 222 if (result == -1) 223 outs() << "Execute failed: " << ErrMsg << "\n"; 224 else 225 outs() << "Crashed with signal #" << abs(result) << "\n"; 226 } 227 if (result & 0x01000000) 228 outs() << "Dumped core\n"; 229 } 230 231 // Was the child successful? 232 return result != 0; 233} 234 235 236/// runPassesOn - Carefully run the specified set of pass on the specified 237/// module, returning the transformed module on success, or a null pointer on 238/// failure. 239Module *BugDriver::runPassesOn(Module *M, 240 const std::vector<const PassInfo*> &Passes, 241 bool AutoDebugCrashes, unsigned NumExtraArgs, 242 const char * const *ExtraArgs) { 243 Module *OldProgram = swapProgramIn(M); 244 std::string BitcodeResult; 245 if (runPasses(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 OldProgram; 251 EmitProgressBitcode("pass-error", false); 252 exit(debugOptimizerCrash()); 253 } 254 swapProgramIn(OldProgram); 255 return 0; 256 } 257 258 // Restore the current program. 259 swapProgramIn(OldProgram); 260 261 Module *Ret = ParseInputFile(BitcodeResult, Context); 262 if (Ret == 0) { 263 errs() << getToolName() << ": Error reading bitcode file '" 264 << BitcodeResult << "'!\n"; 265 exit(1); 266 } 267 sys::Path(BitcodeResult).eraseFromDisk(); // No longer need the file on disk 268 return Ret; 269} 270