1 //===- BugDriver.cpp - Top-Level BugPoint class implementation ------------===// 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 class contains all of the shared state and information that is used by 11 // the BugPoint tool to track down errors in optimizations. This class is the 12 // main driver class that invokes all sub-functionality. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "BugDriver.h" 17 #include "ToolRunner.h" 18 #include "llvm/IR/Module.h" 19 #include "llvm/IRReader/IRReader.h" 20 #include "llvm/Linker/Linker.h" 21 #include "llvm/Pass.h" 22 #include "llvm/Support/CommandLine.h" 23 #include "llvm/Support/FileUtilities.h" 24 #include "llvm/Support/Host.h" 25 #include "llvm/Support/SourceMgr.h" 26 #include "llvm/Support/raw_ostream.h" 27 #include <memory> 28 using namespace llvm; 29 30 namespace llvm { 31 Triple TargetTriple; 32 } 33 34 // Anonymous namespace to define command line options for debugging. 35 // 36 namespace { 37 // Output - The user can specify a file containing the expected output of the 38 // program. If this filename is set, it is used as the reference diff source, 39 // otherwise the raw input run through an interpreter is used as the reference 40 // source. 41 // 42 cl::opt<std::string> 43 OutputFile("output", cl::desc("Specify a reference program output " 44 "(for miscompilation detection)")); 45 } 46 47 /// setNewProgram - If we reduce or update the program somehow, call this method 48 /// to update bugdriver with it. This deletes the old module and sets the 49 /// specified one as the current program. 50 void BugDriver::setNewProgram(Module *M) { 51 delete Program; 52 Program = M; 53 } 54 55 56 /// getPassesString - Turn a list of passes into a string which indicates the 57 /// command line options that must be passed to add the passes. 58 /// 59 std::string llvm::getPassesString(const std::vector<std::string> &Passes) { 60 std::string Result; 61 for (unsigned i = 0, e = Passes.size(); i != e; ++i) { 62 if (i) Result += " "; 63 Result += "-"; 64 Result += Passes[i]; 65 } 66 return Result; 67 } 68 69 BugDriver::BugDriver(const char *toolname, bool find_bugs, 70 unsigned timeout, unsigned memlimit, bool use_valgrind, 71 LLVMContext& ctxt) 72 : Context(ctxt), ToolName(toolname), ReferenceOutputFile(OutputFile), 73 Program(nullptr), Interpreter(nullptr), SafeInterpreter(nullptr), 74 gcc(nullptr), run_find_bugs(find_bugs), Timeout(timeout), 75 MemoryLimit(memlimit), UseValgrind(use_valgrind) {} 76 77 BugDriver::~BugDriver() { 78 delete Program; 79 if (Interpreter != SafeInterpreter) 80 delete Interpreter; 81 delete SafeInterpreter; 82 delete gcc; 83 } 84 85 86 /// ParseInputFile - Given a bitcode or assembly input filename, parse and 87 /// return it, or return null if not possible. 88 /// 89 Module *llvm::ParseInputFile(const std::string &Filename, 90 LLVMContext& Ctxt) { 91 SMDiagnostic Err; 92 Module *Result = ParseIRFile(Filename, Err, Ctxt); 93 if (!Result) 94 Err.print("bugpoint", errs()); 95 96 // If we don't have an override triple, use the first one to configure 97 // bugpoint, or use the host triple if none provided. 98 if (Result) { 99 if (TargetTriple.getTriple().empty()) { 100 Triple TheTriple(Result->getTargetTriple()); 101 102 if (TheTriple.getTriple().empty()) 103 TheTriple.setTriple(sys::getDefaultTargetTriple()); 104 105 TargetTriple.setTriple(TheTriple.getTriple()); 106 } 107 108 Result->setTargetTriple(TargetTriple.getTriple()); // override the triple 109 } 110 return Result; 111 } 112 113 // This method takes the specified list of LLVM input files, attempts to load 114 // them, either as assembly or bitcode, then link them together. It returns 115 // true on failure (if, for example, an input bitcode file could not be 116 // parsed), and false on success. 117 // 118 bool BugDriver::addSources(const std::vector<std::string> &Filenames) { 119 assert(!Program && "Cannot call addSources multiple times!"); 120 assert(!Filenames.empty() && "Must specify at least on input filename!"); 121 122 // Load the first input file. 123 Program = ParseInputFile(Filenames[0], Context); 124 if (!Program) return true; 125 126 outs() << "Read input file : '" << Filenames[0] << "'\n"; 127 128 for (unsigned i = 1, e = Filenames.size(); i != e; ++i) { 129 std::unique_ptr<Module> M(ParseInputFile(Filenames[i], Context)); 130 if (!M.get()) return true; 131 132 outs() << "Linking in input file: '" << Filenames[i] << "'\n"; 133 std::string ErrorMessage; 134 if (Linker::LinkModules(Program, M.get(), Linker::DestroySource, 135 &ErrorMessage)) { 136 errs() << ToolName << ": error linking in '" << Filenames[i] << "': " 137 << ErrorMessage << '\n'; 138 return true; 139 } 140 } 141 142 outs() << "*** All input ok\n"; 143 144 // All input files read successfully! 145 return false; 146 } 147 148 149 150 /// run - The top level method that is invoked after all of the instance 151 /// variables are set up from command line arguments. 152 /// 153 bool BugDriver::run(std::string &ErrMsg) { 154 if (run_find_bugs) { 155 // Rearrange the passes and apply them to the program. Repeat this process 156 // until the user kills the program or we find a bug. 157 return runManyPasses(PassesToRun, ErrMsg); 158 } 159 160 // If we're not running as a child, the first thing that we must do is 161 // determine what the problem is. Does the optimization series crash the 162 // compiler, or does it produce illegal code? We make the top-level 163 // decision by trying to run all of the passes on the input program, 164 // which should generate a bitcode file. If it does generate a bitcode 165 // file, then we know the compiler didn't crash, so try to diagnose a 166 // miscompilation. 167 if (!PassesToRun.empty()) { 168 outs() << "Running selected passes on program to test for crash: "; 169 if (runPasses(Program, PassesToRun)) 170 return debugOptimizerCrash(); 171 } 172 173 // Set up the execution environment, selecting a method to run LLVM bitcode. 174 if (initializeExecutionEnvironment()) return true; 175 176 // Test to see if we have a code generator crash. 177 outs() << "Running the code generator to test for a crash: "; 178 std::string Error; 179 compileProgram(Program, &Error); 180 if (!Error.empty()) { 181 outs() << Error; 182 return debugCodeGeneratorCrash(ErrMsg); 183 } 184 outs() << '\n'; 185 186 // Run the raw input to see where we are coming from. If a reference output 187 // was specified, make sure that the raw output matches it. If not, it's a 188 // problem in the front-end or the code generator. 189 // 190 bool CreatedOutput = false; 191 if (ReferenceOutputFile.empty()) { 192 outs() << "Generating reference output from raw program: "; 193 if (!createReferenceFile(Program)) { 194 return debugCodeGeneratorCrash(ErrMsg); 195 } 196 CreatedOutput = true; 197 } 198 199 // Make sure the reference output file gets deleted on exit from this 200 // function, if appropriate. 201 std::string ROF(ReferenceOutputFile); 202 FileRemover RemoverInstance(ROF, CreatedOutput && !SaveTemps); 203 204 // Diff the output of the raw program against the reference output. If it 205 // matches, then we assume there is a miscompilation bug and try to 206 // diagnose it. 207 outs() << "*** Checking the code generator...\n"; 208 bool Diff = diffProgram(Program, "", "", false, &Error); 209 if (!Error.empty()) { 210 errs() << Error; 211 return debugCodeGeneratorCrash(ErrMsg); 212 } 213 if (!Diff) { 214 outs() << "\n*** Output matches: Debugging miscompilation!\n"; 215 debugMiscompilation(&Error); 216 if (!Error.empty()) { 217 errs() << Error; 218 return debugCodeGeneratorCrash(ErrMsg); 219 } 220 return false; 221 } 222 223 outs() << "\n*** Input program does not match reference diff!\n"; 224 outs() << "Debugging code generator problem!\n"; 225 bool Failure = debugCodeGenerator(&Error); 226 if (!Error.empty()) { 227 errs() << Error; 228 return debugCodeGeneratorCrash(ErrMsg); 229 } 230 return Failure; 231 } 232 233 void llvm::PrintFunctionList(const std::vector<Function*> &Funcs) { 234 unsigned NumPrint = Funcs.size(); 235 if (NumPrint > 10) NumPrint = 10; 236 for (unsigned i = 0; i != NumPrint; ++i) 237 outs() << " " << Funcs[i]->getName(); 238 if (NumPrint < Funcs.size()) 239 outs() << "... <" << Funcs.size() << " total>"; 240 outs().flush(); 241 } 242 243 void llvm::PrintGlobalVariableList(const std::vector<GlobalVariable*> &GVs) { 244 unsigned NumPrint = GVs.size(); 245 if (NumPrint > 10) NumPrint = 10; 246 for (unsigned i = 0; i != NumPrint; ++i) 247 outs() << " " << GVs[i]->getName(); 248 if (NumPrint < GVs.size()) 249 outs() << "... <" << GVs.size() << " total>"; 250 outs().flush(); 251 } 252
