tools/bugpoint/BugDriver.h

   1 //===- BugDriver.h - Top-Level BugPoint class -------------------*- C++ -*-===//
   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 #ifndef LLVM_TOOLS_BUGPOINT_BUGDRIVER_H
  17 #define LLVM_TOOLS_BUGPOINT_BUGDRIVER_H
  18
  19 #include "llvm/IR/ValueMap.h"
  20 #include "llvm/Support/Error.h"
  21 #include "llvm/Support/FileSystem.h"
  22 #include "llvm/Transforms/Utils/ValueMapper.h"
  23 #include <memory>
  24 #include <string>
  25 #include <vector>
  26
  27 namespace llvm {
  28
  29 class Value;
  30 class PassInfo;
  31 class Module;
  32 class GlobalVariable;
  33 class Function;
  34 class BasicBlock;
  35 class AbstractInterpreter;
  36 class Instruction;
  37 class LLVMContext;
  38
  39 class DebugCrashes;
  40
  41 class CC;
  42
  43 extern bool DisableSimplifyCFG;
  44
  45 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
  46 ///
  47 extern bool BugpointIsInterrupted;
  48
  49 class BugDriver {
  50   LLVMContext &Context;
  51   const char *ToolName;            // argv[0] of bugpoint
  52   std::string ReferenceOutputFile; // Name of `good' output file
  53   std::unique_ptr<Module> Program; // The raw program, linked together
  54   std::vector<std::string> PassesToRun;
  55   AbstractInterpreter *Interpreter;     // How to run the program
  56   AbstractInterpreter *SafeInterpreter; // To generate reference output, etc.
  57   CC *cc;
  58   bool run_find_bugs;
  59   unsigned Timeout;
  60   unsigned MemoryLimit;
  61   bool UseValgrind;
  62
  63   // FIXME: sort out public/private distinctions...
  64   friend class ReducePassList;
  65   friend class ReduceMisCodegenFunctions;
  66
  67 public:
  68   BugDriver(const char *toolname, bool find_bugs, unsigned timeout,
  69             unsigned memlimit, bool use_valgrind, LLVMContext &ctxt);
  70   ~BugDriver();
  71
  72   const char *getToolName() const { return ToolName; }
  73
  74   LLVMContext &getContext() const { return Context; }
  75
  76   // Set up methods... these methods are used to copy information about the
  77   // command line arguments into instance variables of BugDriver.
  78   //
  79   bool addSources(const std::vector<std::string> &FileNames);
  80   void addPass(std::string p) { PassesToRun.push_back(std::move(p)); }
  81   void setPassesToRun(const std::vector<std::string> &PTR) {
  82     PassesToRun = PTR;
  83   }
  84   const std::vector<std::string> &getPassesToRun() const { return PassesToRun; }
  85
  86   /// run - The top level method that is invoked after all of the instance
  87   /// variables are set up from command line arguments. The \p as_child argument
  88   /// indicates whether the driver is to run in parent mode or child mode.
  89   ///
  90   Error run();
  91
  92   /// debugOptimizerCrash - This method is called when some optimizer pass
  93   /// crashes on input.  It attempts to prune down the testcase to something
  94   /// reasonable, and figure out exactly which pass is crashing.
  95   ///
  96   Error debugOptimizerCrash(const std::string &ID = "passes");
  97
  98   /// debugCodeGeneratorCrash - This method is called when the code generator
  99   /// crashes on an input.  It attempts to reduce the input as much as possible
 100   /// while still causing the code generator to crash.
 101   Error debugCodeGeneratorCrash();
 102
 103   /// debugMiscompilation - This method is used when the passes selected are not
 104   /// crashing, but the generated output is semantically different from the
 105   /// input.
 106   Error debugMiscompilation();
 107
 108   /// debugPassMiscompilation - This method is called when the specified pass
 109   /// miscompiles Program as input.  It tries to reduce the testcase to
 110   /// something that smaller that still miscompiles the program.
 111   /// ReferenceOutput contains the filename of the file containing the output we
 112   /// are to match.
 113   ///
 114   bool debugPassMiscompilation(const PassInfo *ThePass,
 115                                const std::string &ReferenceOutput);
 116
 117   /// compileSharedObject - This method creates a SharedObject from a given
 118   /// BitcodeFile for debugging a code generator.
 119   ///
 120   Expected<std::string> compileSharedObject(const std::string &BitcodeFile);
 121
 122   /// debugCodeGenerator - This method narrows down a module to a function or
 123   /// set of functions, using the CBE as a ``safe'' code generator for other
 124   /// functions that are not under consideration.
 125   Error debugCodeGenerator();
 126
 127   /// isExecutingJIT - Returns true if bugpoint is currently testing the JIT
 128   ///
 129   bool isExecutingJIT();
 130
 131   Module &getProgram() const { return *Program; }
 132
 133   /// Set the current module to the specified module, returning the old one.
 134   std::unique_ptr<Module> swapProgramIn(std::unique_ptr<Module> M);
 135
 136   AbstractInterpreter *switchToSafeInterpreter() {
 137     AbstractInterpreter *Old = Interpreter;
 138     Interpreter = (AbstractInterpreter *)SafeInterpreter;
 139     return Old;
 140   }
 141
 142   void switchToInterpreter(AbstractInterpreter *AI) { Interpreter = AI; }
 143
 144   /// If we reduce or update the program somehow, call this method to update
 145   /// bugdriver with it.  This deletes the old module and sets the specified one
 146   /// as the current program.
 147   void setNewProgram(std::unique_ptr<Module> M);
 148
 149   /// Try to compile the specified module. This is used for code generation
 150   /// crash testing.
 151   Error compileProgram(Module &M) const;
 152
 153   /// This method runs "Program", capturing the output of the program to a file.
 154   /// A recommended filename may be optionally specified.
 155   Expected<std::string> executeProgram(const Module &Program,
 156                                        std::string OutputFilename,
 157                                        std::string Bitcode,
 158                                        const std::string &SharedObjects,
 159                                        AbstractInterpreter *AI) const;
 160
 161   /// Used to create reference output with the "safe" backend, if reference
 162   /// output is not provided.  If there is a problem with the code generator
 163   /// (e.g., llc crashes), this will return false and set Error.
 164   Expected<std::string>
 165   executeProgramSafely(const Module &Program,
 166                        const std::string &OutputFile) const;
 167
 168   /// Calls compileProgram and then records the output into ReferenceOutputFile.
 169   /// Returns true if reference file created, false otherwise. Note:
 170   /// initializeExecutionEnvironment should be called BEFORE this function.
 171   Error createReferenceFile(Module &M, const std::string &Filename =
 172                                            "bugpoint.reference.out-%%%%%%%");
 173
 174   /// This method executes the specified module and diffs the output against the
 175   /// file specified by ReferenceOutputFile.  If the output is different, 1 is
 176   /// returned.  If there is a problem with the code generator (e.g., llc
 177   /// crashes), this will return -1 and set Error.
 178   Expected<bool> diffProgram(const Module &Program,
 179                              const std::string &BitcodeFile = "",
 180                              const std::string &SharedObj = "",
 181                              bool RemoveBitcode = false) const;
 182
 183   /// This function is used to output M to a file named "bugpoint-ID.bc".
 184   void EmitProgressBitcode(const Module &M, const std::string &ID,
 185                            bool NoFlyer = false) const;
 186
 187   /// This method clones the current Program and deletes the specified
 188   /// instruction from the cloned module.  It then runs a series of cleanup
 189   /// passes (ADCE and SimplifyCFG) to eliminate any code which depends on the
 190   /// value. The modified module is then returned.
 191   ///
 192   std::unique_ptr<Module> deleteInstructionFromProgram(const Instruction *I,
 193                                                        unsigned Simp);
 194
 195   /// This method clones the current Program and performs a series of cleanups
 196   /// intended to get rid of extra cruft on the module. If the
 197   /// MayModifySemantics argument is true, then the cleanups is allowed to
 198   /// modify how the code behaves.
 199   ///
 200   std::unique_ptr<Module> performFinalCleanups(std::unique_ptr<Module> M,
 201                                                bool MayModifySemantics = false);
 202
 203   /// Given a module, extract up to one loop from it into a new function. This
 204   /// returns null if there are no extractable loops in the program or if the
 205   /// loop extractor crashes.
 206   std::unique_ptr<Module> extractLoop(Module *M);
 207
 208   /// Extract all but the specified basic blocks into their own functions. The
 209   /// only detail is that M is actually a module cloned from the one the BBs are
 210   /// in, so some mapping needs to be performed. If this operation fails for
 211   /// some reason (ie the implementation is buggy), this function should return
 212   /// null, otherwise it returns a new Module.
 213   std::unique_ptr<Module>
 214   extractMappedBlocksFromModule(const std::vector<BasicBlock *> &BBs,
 215                                 Module *M);
 216
 217   /// Carefully run the specified set of pass on the specified/ module,
 218   /// returning the transformed module on success, or a null pointer on failure.
 219   std::unique_ptr<Module> runPassesOn(Module *M,
 220                                       const std::vector<std::string> &Passes,
 221                                       unsigned NumExtraArgs = 0,
 222                                       const char *const *ExtraArgs = nullptr);
 223
 224   /// runPasses - Run the specified passes on Program, outputting a bitcode
 225   /// file and writting the filename into OutputFile if successful.  If the
 226   /// optimizations fail for some reason (optimizer crashes), return true,
 227   /// otherwise return false.  If DeleteOutput is set to true, the bitcode is
 228   /// deleted on success, and the filename string is undefined.  This prints to
 229   /// outs() a single line message indicating whether compilation was successful
 230   /// or failed, unless Quiet is set.  ExtraArgs specifies additional arguments
 231   /// to pass to the child bugpoint instance.
 232   ///
 233   bool runPasses(Module &Program, const std::vector<std::string> &PassesToRun,
 234                  std::string &OutputFilename, bool DeleteOutput = false,
 235                  bool Quiet = false, unsigned NumExtraArgs = 0,
 236                  const char *const *ExtraArgs = nullptr) const;
 237
 238   /// runPasses - Just like the method above, but this just returns true or
 239   /// false indicating whether or not the optimizer crashed on the specified
 240   /// input (true = crashed).  Does not produce any output.
 241   ///
 242   bool runPasses(Module &M, const std::vector<std::string> &PassesToRun) const {
 243     std::string Filename;
 244     return runPasses(M, PassesToRun, Filename, true);
 245   }
 246
 247   /// Take the specified pass list and create different combinations of passes
 248   /// to compile the program with. Compile the program with each set and mark
 249   /// test to see if it compiled correctly. If the passes compiled correctly
 250   /// output nothing and rearrange the passes into a new order. If the passes
 251   /// did not compile correctly, output the command required to recreate the
 252   /// failure.
 253   Error runManyPasses(const std::vector<std::string> &AllPasses);
 254
 255   /// This writes the current "Program" to the named bitcode file.  If an error
 256   /// occurs, true is returned.
 257   bool writeProgramToFile(const std::string &Filename, const Module &M) const;
 258   bool writeProgramToFile(const std::string &Filename, int FD,
 259                           const Module &M) const;
 260   bool writeProgramToFile(int FD, const Module &M) const;
 261
 262 private:
 263   /// initializeExecutionEnvironment - This method is used to set up the
 264   /// environment for executing LLVM programs.
 265   ///
 266   Error initializeExecutionEnvironment();
 267 };
 268
 269 struct DiscardTemp {
 270   sys::fs::TempFile &File;
 271   ~DiscardTemp();
 272 };
 273
 274 ///  Given a bitcode or assembly input filename, parse and return it, or return
 275 ///  null if not possible.
 276 ///
 277 std::unique_ptr<Module> parseInputFile(StringRef InputFilename,
 278                                        LLVMContext &ctxt);
 279
 280 /// getPassesString - Turn a list of passes into a string which indicates the
 281 /// command line options that must be passed to add the passes.
 282 ///
 283 std::string getPassesString(const std::vector<std::string> &Passes);
 284
 285 /// PrintFunctionList - prints out list of problematic functions
 286 ///
 287 void PrintFunctionList(const std::vector<Function *> &Funcs);
 288
 289 /// PrintGlobalVariableList - prints out list of problematic global variables
 290 ///
 291 void PrintGlobalVariableList(const std::vector<GlobalVariable *> &GVs);
 292
 293 // DeleteGlobalInitializer - "Remove" the global variable by deleting its
 294 // initializer, making it external.
 295 //
 296 void DeleteGlobalInitializer(GlobalVariable *GV);
 297
 298 // DeleteFunctionBody - "Remove" the function by deleting all of it's basic
 299 // blocks, making it external.
 300 //
 301 void DeleteFunctionBody(Function *F);
 302
 303 /// Given a module and a list of functions in the module, split the functions
 304 /// OUT of the specified module, and place them in the new module.
 305 std::unique_ptr<Module>
 306 SplitFunctionsOutOfModule(Module *M, const std::vector<Function *> &F,
 307                           ValueToValueMapTy &VMap);
 308
 309 } // End llvm namespace
 310
 311 #endif