tools/bugpoint/BugDriver.cpp

   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/Assembly/Parser.h"
  22 #include "llvm/Bitcode/ReaderWriter.h"
  23 #include "llvm/Support/CommandLine.h"
  24 #include "llvm/Support/FileUtilities.h"
  25 #include "llvm/Support/MemoryBuffer.h"
  26 #include "llvm/Support/raw_ostream.h"
  27 #include <iostream>
  28 #include <memory>
  29 using namespace llvm;
  30
  31 // Anonymous namespace to define command line options for debugging.
  32 //
  33 namespace {
  34   // Output - The user can specify a file containing the expected output of the
  35   // program.  If this filename is set, it is used as the reference diff source,
  36   // otherwise the raw input run through an interpreter is used as the reference
  37   // source.
  38   //
  39   cl::opt<std::string>
  40   OutputFile("output", cl::desc("Specify a reference program output "
  41                                 "(for miscompilation detection)"));
  42 }
  43
  44 /// setNewProgram - If we reduce or update the program somehow, call this method
  45 /// to update bugdriver with it.  This deletes the old module and sets the
  46 /// specified one as the current program.
  47 void BugDriver::setNewProgram(Module *M) {
  48   delete Program;
  49   Program = M;
  50 }
  51
  52
  53 /// getPassesString - Turn a list of passes into a string which indicates the
  54 /// command line options that must be passed to add the passes.
  55 ///
  56 std::string llvm::getPassesString(const std::vector<const PassInfo*> &Passes) {
  57   std::string Result;
  58   for (unsigned i = 0, e = Passes.size(); i != e; ++i) {
  59     if (i) Result += " ";
  60     Result += "-";
  61     Result += Passes[i]->getPassArgument();
  62   }
  63   return Result;
  64 }
  65
  66 BugDriver::BugDriver(const char *toolname, bool as_child, bool find_bugs,
  67                      unsigned timeout, unsigned memlimit)
  68   : ToolName(toolname), ReferenceOutputFile(OutputFile),
  69     Program(0), Interpreter(0), SafeInterpreter(0), gcc(0),
  70     run_as_child(as_child),
  71     run_find_bugs(find_bugs), Timeout(timeout), MemoryLimit(memlimit) {}
  72
  73
  74 /// ParseInputFile - Given a bitcode or assembly input filename, parse and
  75 /// return it, or return null if not possible.
  76 ///
  77 Module *llvm::ParseInputFile(const std::string &Filename) {
  78   std::auto_ptr<MemoryBuffer> Buffer(MemoryBuffer::getFileOrSTDIN(Filename));
  79   Module *Result = 0;
  80   if (Buffer.get())
  81     Result = ParseBitcodeFile(Buffer.get());
  82
  83   ParseError Err;
  84   if (!Result && !(Result = ParseAssemblyFile(Filename, Err))) {
  85     Err.PrintError("bugpoint", errs());
  86     Result = 0;
  87   }
  88
  89   return Result;
  90 }
  91
  92 // This method takes the specified list of LLVM input files, attempts to load
  93 // them, either as assembly or bitcode, then link them together. It returns
  94 // true on failure (if, for example, an input bitcode file could not be
  95 // parsed), and false on success.
  96 //
  97 bool BugDriver::addSources(const std::vector<std::string> &Filenames) {
  98   assert(Program == 0 && "Cannot call addSources multiple times!");
  99   assert(!Filenames.empty() && "Must specify at least on input filename!");
 100
 101   try {
 102     // Load the first input file.
 103     Program = ParseInputFile(Filenames[0]);
 104     if (Program == 0) return true;
 105
 106     if (!run_as_child)
 107       std::cout << "Read input file      : '" << Filenames[0] << "'\n";
 108
 109     for (unsigned i = 1, e = Filenames.size(); i != e; ++i) {
 110       std::auto_ptr<Module> M(ParseInputFile(Filenames[i]));
 111       if (M.get() == 0) return true;
 112
 113       if (!run_as_child)
 114         std::cout << "Linking in input file: '" << Filenames[i] << "'\n";
 115       std::string ErrorMessage;
 116       if (Linker::LinkModules(Program, M.get(), &ErrorMessage)) {
 117         std::cerr << ToolName << ": error linking in '" << Filenames[i] << "': "
 118                   << ErrorMessage << '\n';
 119         return true;
 120       }
 121     }
 122   } catch (const std::string &Error) {
 123     std::cerr << ToolName << ": error reading input '" << Error << "'\n";
 124     return true;
 125   }
 126
 127   if (!run_as_child)
 128     std::cout << "*** All input ok\n";
 129
 130   // All input files read successfully!
 131   return false;
 132 }
 133
 134
 135
 136 /// run - The top level method that is invoked after all of the instance
 137 /// variables are set up from command line arguments.
 138 ///
 139 bool BugDriver::run() {
 140   // The first thing to do is determine if we're running as a child. If we are,
 141   // then what to do is very narrow. This form of invocation is only called
 142   // from the runPasses method to actually run those passes in a child process.
 143   if (run_as_child) {
 144     // Execute the passes
 145     return runPassesAsChild(PassesToRun);
 146   }
 147
 148   if (run_find_bugs) {
 149     // Rearrange the passes and apply them to the program. Repeat this process
 150     // until the user kills the program or we find a bug.
 151     return runManyPasses(PassesToRun);
 152   }
 153
 154   // If we're not running as a child, the first thing that we must do is
 155   // determine what the problem is. Does the optimization series crash the
 156   // compiler, or does it produce illegal code?  We make the top-level
 157   // decision by trying to run all of the passes on the the input program,
 158   // which should generate a bitcode file.  If it does generate a bitcode
 159   // file, then we know the compiler didn't crash, so try to diagnose a
 160   // miscompilation.
 161   if (!PassesToRun.empty()) {
 162     std::cout << "Running selected passes on program to test for crash: ";
 163     if (runPasses(PassesToRun))
 164       return debugOptimizerCrash();
 165   }
 166
 167   // Set up the execution environment, selecting a method to run LLVM bitcode.
 168   if (initializeExecutionEnvironment()) return true;
 169
 170   // Test to see if we have a code generator crash.
 171   std::cout << "Running the code generator to test for a crash: ";
 172   try {
 173     compileProgram(Program);
 174     std::cout << '\n';
 175   } catch (ToolExecutionError &TEE) {
 176     std::cout << TEE.what();
 177     return debugCodeGeneratorCrash();
 178   }
 179
 180
 181   // Run the raw input to see where we are coming from.  If a reference output
 182   // was specified, make sure that the raw output matches it.  If not, it's a
 183   // problem in the front-end or the code generator.
 184   //
 185   bool CreatedOutput = false;
 186   if (ReferenceOutputFile.empty()) {
 187     std::cout << "Generating reference output from raw program: ";
 188     if(!createReferenceFile(Program)){
 189       return debugCodeGeneratorCrash();
 190     }
 191     CreatedOutput = true;
 192   }
 193
 194   // Make sure the reference output file gets deleted on exit from this
 195   // function, if appropriate.
 196   sys::Path ROF(ReferenceOutputFile);
 197   FileRemover RemoverInstance(ROF, CreatedOutput);
 198
 199   // Diff the output of the raw program against the reference output.  If it
 200   // matches, then we assume there is a miscompilation bug and try to
 201   // diagnose it.
 202   std::cout << "*** Checking the code generator...\n";
 203   try {
 204     if (!diffProgram()) {
 205       std::cout << "\n*** Debugging miscompilation!\n";
 206       return debugMiscompilation();
 207     }
 208   } catch (ToolExecutionError &TEE) {
 209     std::cerr << TEE.what();
 210     return debugCodeGeneratorCrash();
 211   }
 212
 213   std::cout << "\n*** Input program does not match reference diff!\n";
 214   std::cout << "Debugging code generator problem!\n";
 215   try {
 216     return debugCodeGenerator();
 217   } catch (ToolExecutionError &TEE) {
 218     std::cerr << TEE.what();
 219     return debugCodeGeneratorCrash();
 220   }
 221 }
 222
 223 void llvm::PrintFunctionList(const std::vector<Function*> &Funcs) {
 224   unsigned NumPrint = Funcs.size();
 225   if (NumPrint > 10) NumPrint = 10;
 226   for (unsigned i = 0; i != NumPrint; ++i)
 227     std::cout << " " << Funcs[i]->getName();
 228   if (NumPrint < Funcs.size())
 229     std::cout << "... <" << Funcs.size() << " total>";
 230   std::cout << std::flush;
 231 }
 232
 233 void llvm::PrintGlobalVariableList(const std::vector<GlobalVariable*> &GVs) {
 234   unsigned NumPrint = GVs.size();
 235   if (NumPrint > 10) NumPrint = 10;
 236   for (unsigned i = 0; i != NumPrint; ++i)
 237     std::cout << " " << GVs[i]->getName();
 238   if (NumPrint < GVs.size())
 239     std::cout << "... <" << GVs.size() << " total>";
 240   std::cout << std::flush;
 241 }