BugDriver.cpp revision 8be3291f5942e3ae4a5d66c480e7aabe2f771031
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/Linker.h" 19#include "llvm/Module.h" 20#include "llvm/Pass.h" 21#include "llvm/Support/IRReader.h" 22#include "llvm/Support/CommandLine.h" 23#include "llvm/Support/FileUtilities.h" 24#include "llvm/Support/SourceMgr.h" 25#include "llvm/Support/raw_ostream.h" 26#include "llvm/System/Host.h" 27#include <memory> 28using namespace llvm; 29 30namespace llvm { 31 Triple TargetTriple; 32} 33 34// Anonymous namespace to define command line options for debugging. 35// 36namespace { 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. 50void 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/// 59std::string llvm::getPassesString(const std::vector<const PassInfo*> &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]->getPassArgument(); 65 } 66 return Result; 67} 68 69BugDriver::BugDriver(const char *toolname, bool as_child, bool find_bugs, 70 unsigned timeout, unsigned memlimit, bool use_valgrind, 71 LLVMContext& ctxt) 72 : Context(ctxt), ToolName(toolname), ReferenceOutputFile(OutputFile), 73 Program(0), Interpreter(0), SafeInterpreter(0), gcc(0), 74 run_as_child(as_child), run_find_bugs(find_bugs), Timeout(timeout), 75 MemoryLimit(memlimit), UseValgrind(use_valgrind) {} 76 77BugDriver::~BugDriver() { 78 delete Program; 79} 80 81 82/// ParseInputFile - Given a bitcode or assembly input filename, parse and 83/// return it, or return null if not possible. 84/// 85Module *llvm::ParseInputFile(const std::string &Filename, 86 LLVMContext& Ctxt) { 87 SMDiagnostic Err; 88 Module *Result = ParseIRFile(Filename, Err, Ctxt); 89 if (!Result) 90 Err.Print("bugpoint", errs()); 91 92 // If we don't have an override triple, use the first one to configure 93 // bugpoint, or use the host triple if none provided. 94 if (Result) { 95 if (TargetTriple.getTriple().empty()) { 96 Triple TheTriple(Result->getTargetTriple()); 97 98 if (TheTriple.getTriple().empty()) 99 TheTriple.setTriple(sys::getHostTriple()); 100 101 TargetTriple.setTriple(TheTriple.getTriple()); 102 } 103 104 Result->setTargetTriple(TargetTriple.getTriple()); // override the triple 105 } 106 return Result; 107} 108 109// This method takes the specified list of LLVM input files, attempts to load 110// them, either as assembly or bitcode, then link them together. It returns 111// true on failure (if, for example, an input bitcode file could not be 112// parsed), and false on success. 113// 114bool BugDriver::addSources(const std::vector<std::string> &Filenames) { 115 assert(Program == 0 && "Cannot call addSources multiple times!"); 116 assert(!Filenames.empty() && "Must specify at least on input filename!"); 117 118 // Load the first input file. 119 Program = ParseInputFile(Filenames[0], Context); 120 if (Program == 0) return true; 121 122 if (!run_as_child) 123 outs() << "Read input file : '" << Filenames[0] << "'\n"; 124 125 for (unsigned i = 1, e = Filenames.size(); i != e; ++i) { 126 std::auto_ptr<Module> M(ParseInputFile(Filenames[i], Context)); 127 if (M.get() == 0) return true; 128 129 if (!run_as_child) 130 outs() << "Linking in input file: '" << Filenames[i] << "'\n"; 131 std::string ErrorMessage; 132 if (Linker::LinkModules(Program, M.get(), &ErrorMessage)) { 133 errs() << ToolName << ": error linking in '" << Filenames[i] << "': " 134 << ErrorMessage << '\n'; 135 return true; 136 } 137 } 138 139 if (!run_as_child) 140 outs() << "*** All input ok\n"; 141 142 // All input files read successfully! 143 return false; 144} 145 146 147 148/// run - The top level method that is invoked after all of the instance 149/// variables are set up from command line arguments. 150/// 151bool BugDriver::run(std::string &ErrMsg) { 152 // The first thing to do is determine if we're running as a child. If we are, 153 // then what to do is very narrow. This form of invocation is only called 154 // from the runPasses method to actually run those passes in a child process. 155 if (run_as_child) { 156 // Execute the passes 157 return runPassesAsChild(PassesToRun); 158 } 159 160 if (run_find_bugs) { 161 // Rearrange the passes and apply them to the program. Repeat this process 162 // until the user kills the program or we find a bug. 163 return runManyPasses(PassesToRun, ErrMsg); 164 } 165 166 // If we're not running as a child, the first thing that we must do is 167 // determine what the problem is. Does the optimization series crash the 168 // compiler, or does it produce illegal code? We make the top-level 169 // decision by trying to run all of the passes on the the input program, 170 // which should generate a bitcode file. If it does generate a bitcode 171 // file, then we know the compiler didn't crash, so try to diagnose a 172 // miscompilation. 173 if (!PassesToRun.empty()) { 174 outs() << "Running selected passes on program to test for crash: "; 175 if (runPasses(PassesToRun)) 176 return debugOptimizerCrash(); 177 } 178 179 // Set up the execution environment, selecting a method to run LLVM bitcode. 180 if (initializeExecutionEnvironment()) return true; 181 182 // Test to see if we have a code generator crash. 183 outs() << "Running the code generator to test for a crash: "; 184 std::string Error; 185 compileProgram(Program, &Error); 186 if (!Error.empty()) { 187 outs() << Error; 188 return debugCodeGeneratorCrash(ErrMsg); 189 } 190 outs() << '\n'; 191 192 // Run the raw input to see where we are coming from. If a reference output 193 // was specified, make sure that the raw output matches it. If not, it's a 194 // problem in the front-end or the code generator. 195 // 196 bool CreatedOutput = false; 197 if (ReferenceOutputFile.empty()) { 198 outs() << "Generating reference output from raw program: "; 199 if (!createReferenceFile(Program)) { 200 return debugCodeGeneratorCrash(ErrMsg); 201 } 202 CreatedOutput = true; 203 } 204 205 // Make sure the reference output file gets deleted on exit from this 206 // function, if appropriate. 207 sys::Path ROF(ReferenceOutputFile); 208 FileRemover RemoverInstance(ROF, CreatedOutput && !SaveTemps); 209 210 // Diff the output of the raw program against the reference output. If it 211 // matches, then we assume there is a miscompilation bug and try to 212 // diagnose it. 213 outs() << "*** Checking the code generator...\n"; 214 bool Diff = diffProgram("", "", false, &Error); 215 if (!Error.empty()) { 216 errs() << Error; 217 return debugCodeGeneratorCrash(ErrMsg); 218 } 219 if (!Diff) { 220 outs() << "\n*** Output matches: Debugging miscompilation!\n"; 221 debugMiscompilation(&Error); 222 if (!Error.empty()) { 223 errs() << Error; 224 return debugCodeGeneratorCrash(ErrMsg); 225 } 226 return false; 227 } 228 229 outs() << "\n*** Input program does not match reference diff!\n"; 230 outs() << "Debugging code generator problem!\n"; 231 bool Failure = debugCodeGenerator(&Error); 232 if (!Error.empty()) { 233 errs() << Error; 234 return debugCodeGeneratorCrash(ErrMsg); 235 } 236 return Failure; 237} 238 239void llvm::PrintFunctionList(const std::vector<Function*> &Funcs) { 240 unsigned NumPrint = Funcs.size(); 241 if (NumPrint > 10) NumPrint = 10; 242 for (unsigned i = 0; i != NumPrint; ++i) 243 outs() << " " << Funcs[i]->getName(); 244 if (NumPrint < Funcs.size()) 245 outs() << "... <" << Funcs.size() << " total>"; 246 outs().flush(); 247} 248 249void llvm::PrintGlobalVariableList(const std::vector<GlobalVariable*> &GVs) { 250 unsigned NumPrint = GVs.size(); 251 if (NumPrint > 10) NumPrint = 10; 252 for (unsigned i = 0; i != NumPrint; ++i) 253 outs() << " " << GVs[i]->getName(); 254 if (NumPrint < GVs.size()) 255 outs() << "... <" << GVs.size() << " total>"; 256 outs().flush(); 257} 258