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/SourceMgr.h"
  27 #include "llvm/Support/raw_ostream.h"
  28 #include "llvm/System/Host.h"
  29 #include <memory>
  30 using namespace llvm;
  31
  32 namespace llvm {
  33   Triple TargetTriple;
  34 }
  35
  36 // Anonymous namespace to define command line options for debugging.
  37 //
  38 namespace {
  39   // Output - The user can specify a file containing the expected output of the
  40   // program.  If this filename is set, it is used as the reference diff source,
  41   // otherwise the raw input run through an interpreter is used as the reference
  42   // source.
  43   //
  44   cl::opt<std::string>
  45   OutputFile("output", cl::desc("Specify a reference program output "
  46                                 "(for miscompilation detection)"));
  47 }
  48
  49 /// setNewProgram - If we reduce or update the program somehow, call this method
  50 /// to update bugdriver with it.  This deletes the old module and sets the
  51 /// specified one as the current program.
  52 void BugDriver::setNewProgram(Module *M) {
  53   delete Program;
  54   Program = M;
  55 }
  56
  57
  58 /// getPassesString - Turn a list of passes into a string which indicates the
  59 /// command line options that must be passed to add the passes.
  60 ///
  61 std::string llvm::getPassesString(const std::vector<const PassInfo*> &Passes) {
  62   std::string Result;
  63   for (unsigned i = 0, e = Passes.size(); i != e; ++i) {
  64     if (i) Result += " ";
  65     Result += "-";
  66     Result += Passes[i]->getPassArgument();
  67   }
  68   return Result;
  69 }
  70
  71 BugDriver::BugDriver(const char *toolname, bool as_child, bool find_bugs,
  72                      unsigned timeout, unsigned memlimit,
  73                      LLVMContext& ctxt)
  74   : Context(ctxt), ToolName(toolname), ReferenceOutputFile(OutputFile),
  75     Program(0), Interpreter(0), SafeInterpreter(0), gcc(0),
  76     run_as_child(as_child), run_find_bugs(find_bugs), Timeout(timeout),
  77     MemoryLimit(memlimit)  {}
  78
  79
  80 /// ParseInputFile - Given a bitcode or assembly input filename, parse and
  81 /// return it, or return null if not possible.
  82 ///
  83 Module *llvm::ParseInputFile(const std::string &Filename,
  84                              LLVMContext& Ctxt) {
  85   std::auto_ptr<MemoryBuffer> Buffer(MemoryBuffer::getFileOrSTDIN(Filename));
  86   Module *Result = 0;
  87   if (Buffer.get())
  88     Result = ParseBitcodeFile(Buffer.get(), Ctxt);
  89
  90   SMDiagnostic Err;
  91   if (!Result && !(Result = ParseAssemblyFile(Filename, Err, Ctxt))) {
  92     Err.Print("bugpoint", errs());
  93     Result = 0;
  94   }
  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::getHostTriple());
 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 == 0 && "Cannot call addSources multiple times!");
 120   assert(!Filenames.empty() && "Must specify at least on input filename!");
 121
 122   try {
 123     // Load the first input file.
 124     Program = ParseInputFile(Filenames[0], Context);
 125     if (Program == 0) return true;
 126
 127     if (!run_as_child)
 128       outs() << "Read input file      : '" << Filenames[0] << "'\n";
 129
 130     for (unsigned i = 1, e = Filenames.size(); i != e; ++i) {
 131       std::auto_ptr<Module> M(ParseInputFile(Filenames[i], Context));
 132       if (M.get() == 0) return true;
 133
 134       if (!run_as_child)
 135         outs() << "Linking in input file: '" << Filenames[i] << "'\n";
 136       std::string ErrorMessage;
 137       if (Linker::LinkModules(Program, M.get(), &ErrorMessage)) {
 138         errs() << ToolName << ": error linking in '" << Filenames[i] << "': "
 139                << ErrorMessage << '\n';
 140         return true;
 141       }
 142     }
 143   } catch (const std::string &Error) {
 144     errs() << ToolName << ": error reading input '" << Error << "'\n";
 145     return true;
 146   }
 147
 148   if (!run_as_child)
 149     outs() << "*** All input ok\n";
 150
 151   // All input files read successfully!
 152   return false;
 153 }
 154
 155
 156
 157 /// run - The top level method that is invoked after all of the instance
 158 /// variables are set up from command line arguments.
 159 ///
 160 bool BugDriver::run() {
 161   // The first thing to do is determine if we're running as a child. If we are,
 162   // then what to do is very narrow. This form of invocation is only called
 163   // from the runPasses method to actually run those passes in a child process.
 164   if (run_as_child) {
 165     // Execute the passes
 166     return runPassesAsChild(PassesToRun);
 167   }
 168
 169   if (run_find_bugs) {
 170     // Rearrange the passes and apply them to the program. Repeat this process
 171     // until the user kills the program or we find a bug.
 172     return runManyPasses(PassesToRun);
 173   }
 174
 175   // If we're not running as a child, the first thing that we must do is
 176   // determine what the problem is. Does the optimization series crash the
 177   // compiler, or does it produce illegal code?  We make the top-level
 178   // decision by trying to run all of the passes on the the input program,
 179   // which should generate a bitcode file.  If it does generate a bitcode
 180   // file, then we know the compiler didn't crash, so try to diagnose a
 181   // miscompilation.
 182   if (!PassesToRun.empty()) {
 183     outs() << "Running selected passes on program to test for crash: ";
 184     if (runPasses(PassesToRun))
 185       return debugOptimizerCrash();
 186   }
 187
 188   // Set up the execution environment, selecting a method to run LLVM bitcode.
 189   if (initializeExecutionEnvironment()) return true;
 190
 191   // Test to see if we have a code generator crash.
 192   outs() << "Running the code generator to test for a crash: ";
 193   try {
 194     compileProgram(Program);
 195     outs() << '\n';
 196   } catch (ToolExecutionError &TEE) {
 197     outs() << TEE.what();
 198     return debugCodeGeneratorCrash();
 199   }
 200
 201
 202   // Run the raw input to see where we are coming from.  If a reference output
 203   // was specified, make sure that the raw output matches it.  If not, it's a
 204   // problem in the front-end or the code generator.
 205   //
 206   bool CreatedOutput = false;
 207   if (ReferenceOutputFile.empty()) {
 208     outs() << "Generating reference output from raw program: ";
 209     if(!createReferenceFile(Program)){
 210       return debugCodeGeneratorCrash();
 211     }
 212     CreatedOutput = true;
 213   }
 214
 215   // Make sure the reference output file gets deleted on exit from this
 216   // function, if appropriate.
 217   sys::Path ROF(ReferenceOutputFile);
 218   FileRemover RemoverInstance(ROF, CreatedOutput && !SaveTemps);
 219
 220   // Diff the output of the raw program against the reference output.  If it
 221   // matches, then we assume there is a miscompilation bug and try to
 222   // diagnose it.
 223   outs() << "*** Checking the code generator...\n";
 224   try {
 225     if (!diffProgram()) {
 226       outs() << "\n*** Output matches: Debugging miscompilation!\n";
 227       return debugMiscompilation();
 228     }
 229   } catch (ToolExecutionError &TEE) {
 230     errs() << TEE.what();
 231     return debugCodeGeneratorCrash();
 232   }
 233
 234   outs() << "\n*** Input program does not match reference diff!\n";
 235   outs() << "Debugging code generator problem!\n";
 236   try {
 237     return debugCodeGenerator();
 238   } catch (ToolExecutionError &TEE) {
 239     errs() << TEE.what();
 240     return debugCodeGeneratorCrash();
 241   }
 242 }
 243
 244 void llvm::PrintFunctionList(const std::vector<Function*> &Funcs) {
 245   unsigned NumPrint = Funcs.size();
 246   if (NumPrint > 10) NumPrint = 10;
 247   for (unsigned i = 0; i != NumPrint; ++i)
 248     outs() << " " << Funcs[i]->getName();
 249   if (NumPrint < Funcs.size())
 250     outs() << "... <" << Funcs.size() << " total>";
 251   outs().flush();
 252 }
 253
 254 void llvm::PrintGlobalVariableList(const std::vector<GlobalVariable*> &GVs) {
 255   unsigned NumPrint = GVs.size();
 256   if (NumPrint > 10) NumPrint = 10;
 257   for (unsigned i = 0; i != NumPrint; ++i)
 258     outs() << " " << GVs[i]->getName();
 259   if (NumPrint < GVs.size())
 260     outs() << "... <" << GVs.size() << " total>";
 261   outs().flush();
 262 }