llvm/tools/bugpoint/BugDriver.h

   1 //===- BugDriver.h - Top-Level BugPoint class -------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This class contains all of the shared state and information that is used by
  10 // the BugPoint tool to track down errors in optimizations.  This class is the
  11 // main driver class that invokes all sub-functionality.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_TOOLS_BUGPOINT_BUGDRIVER_H
  16 #define LLVM_TOOLS_BUGPOINT_BUGDRIVER_H
  17
  18 #include "llvm/IR/ValueMap.h"
  19 #include "llvm/Support/Error.h"
  20 #include "llvm/Support/FileSystem.h"
  21 #include "llvm/Transforms/Utils/ValueMapper.h"
  22 #include <memory>
  23 #include <string>
  24 #include <vector>
  25
  26 namespace llvm {
  27
  28 class Module;
  29 class GlobalVariable;
  30 class Function;
  31 class BasicBlock;
  32 class AbstractInterpreter;
  33 class Instruction;
  34 class LLVMContext;
  35
  36 class CC;
  37
  38 extern bool DisableSimplifyCFG;
  39
  40 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
  41 ///
  42 extern bool BugpointIsInterrupted;
  43
  44 class BugDriver {
  45   LLVMContext &Context;
  46   const char *ToolName;            // argv[0] of bugpoint
  47   std::string ReferenceOutputFile; // Name of `good' output file
  48   std::unique_ptr<Module> Program; // The raw program, linked together
  49   std::vector<std::string> PassesToRun;
  50   AbstractInterpreter *Interpreter;     // How to run the program
  51   AbstractInterpreter *SafeInterpreter; // To generate reference output, etc.
  52   CC *cc;
  53   bool run_find_bugs;
  54   unsigned Timeout;
  55   unsigned MemoryLimit;
  56   bool UseValgrind;
  57
  58   // FIXME: sort out public/private distinctions...
  59   friend class ReducePassList;
  60   friend class ReduceMisCodegenFunctions;
  61
  62 public:
  63   BugDriver(const char *toolname, bool find_bugs, unsigned timeout,
  64             unsigned memlimit, bool use_valgrind, LLVMContext &ctxt);
  65   ~BugDriver();
  66
  67   const char *getToolName() const { return ToolName; }
  68
  69   LLVMContext &getContext() const { return Context; }
  70
  71   // Set up methods... these methods are used to copy information about the
  72   // command line arguments into instance variables of BugDriver.
  73   //
  74   bool addSources(const std::vector<std::string> &FileNames);
  75   void addPass(std::string p) { PassesToRun.push_back(std::move(p)); }
  76   void setPassesToRun(const std::vector<std::string> &PTR) {
  77     PassesToRun = PTR;
  78   }
  79   const std::vector<std::string> &getPassesToRun() const { return PassesToRun; }
  80
  81   /// run - The top level method that is invoked after all of the instance
  82   /// variables are set up from command line arguments. The \p as_child argument
  83   /// indicates whether the driver is to run in parent mode or child mode.
  84   ///
  85   Error run();
  86
  87   /// debugOptimizerCrash - This method is called when some optimizer pass
  88   /// crashes on input.  It attempts to prune down the testcase to something
  89   /// reasonable, and figure out exactly which pass is crashing.
  90   ///
  91   Error debugOptimizerCrash(const std::string &ID = "passes");
  92
  93   /// debugCodeGeneratorCrash - This method is called when the code generator
  94   /// crashes on an input.  It attempts to reduce the input as much as possible
  95   /// while still causing the code generator to crash.
  96   Error debugCodeGeneratorCrash();
  97
  98   /// debugMiscompilation - This method is used when the passes selected are not
  99   /// crashing, but the generated output is semantically different from the
 100   /// input.
 101   Error debugMiscompilation();
 102
 103   /// compileSharedObject - This method creates a SharedObject from a given
 104   /// BitcodeFile for debugging a code generator.
 105   ///
 106   Expected<std::string> compileSharedObject(const std::string &BitcodeFile);
 107
 108   /// debugCodeGenerator - This method narrows down a module to a function or
 109   /// set of functions, using the CBE as a ``safe'' code generator for other
 110   /// functions that are not under consideration.
 111   Error debugCodeGenerator();
 112
 113   /// isExecutingJIT - Returns true if bugpoint is currently testing the JIT
 114   ///
 115   bool isExecutingJIT();
 116
 117   Module &getProgram() const { return *Program; }
 118
 119   /// Set the current module to the specified module, returning the old one.
 120   std::unique_ptr<Module> swapProgramIn(std::unique_ptr<Module> M);
 121
 122   AbstractInterpreter *switchToSafeInterpreter() {
 123     AbstractInterpreter *Old = Interpreter;
 124     Interpreter = (AbstractInterpreter *)SafeInterpreter;
 125     return Old;
 126   }
 127
 128   void switchToInterpreter(AbstractInterpreter *AI) { Interpreter = AI; }
 129
 130   /// If we reduce or update the program somehow, call this method to update
 131   /// bugdriver with it.  This deletes the old module and sets the specified one
 132   /// as the current program.
 133   void setNewProgram(std::unique_ptr<Module> M);
 134
 135   /// Try to compile the specified module. This is used for code generation
 136   /// crash testing.
 137   Error compileProgram(Module &M) const;
 138
 139   /// This method runs "Program", capturing the output of the program to a file.
 140   /// A recommended filename may be optionally specified.
 141   Expected<std::string> executeProgram(const Module &Program,
 142                                        std::string OutputFilename,
 143                                        std::string Bitcode,
 144                                        const std::string &SharedObjects,
 145                                        AbstractInterpreter *AI) const;
 146
 147   /// Used to create reference output with the "safe" backend, if reference
 148   /// output is not provided.  If there is a problem with the code generator
 149   /// (e.g., llc crashes), this will return false and set Error.
 150   Expected<std::string>
 151   executeProgramSafely(const Module &Program,
 152                        const std::string &OutputFile) const;
 153
 154   /// Calls compileProgram and then records the output into ReferenceOutputFile.
 155   /// Returns true if reference file created, false otherwise. Note:
 156   /// initializeExecutionEnvironment should be called BEFORE this function.
 157   Error createReferenceFile(Module &M, const std::string &Filename =
 158                                            "bugpoint.reference.out-%%%%%%%");
 159
 160   /// This method executes the specified module and diffs the output against the
 161   /// file specified by ReferenceOutputFile.  If the output is different, 1 is
 162   /// returned.  If there is a problem with the code generator (e.g., llc
 163   /// crashes), this will return -1 and set Error.
 164   Expected<bool> diffProgram(const Module &Program,
 165                              const std::string &BitcodeFile = "",
 166                              const std::string &SharedObj = "",
 167                              bool RemoveBitcode = false) const;
 168
 169   /// This function is used to output M to a file named "bugpoint-ID.bc".
 170   void EmitProgressBitcode(const Module &M, const std::string &ID,
 171                            bool NoFlyer = false) const;
 172
 173   /// This method clones the current Program and deletes the specified
 174   /// instruction from the cloned module.  It then runs a series of cleanup
 175   /// passes (ADCE and SimplifyCFG) to eliminate any code which depends on the
 176   /// value. The modified module is then returned.
 177   ///
 178   std::unique_ptr<Module> deleteInstructionFromProgram(const Instruction *I,
 179                                                        unsigned Simp);
 180
 181   /// This method clones the current Program and performs a series of cleanups
 182   /// intended to get rid of extra cruft on the module. If the
 183   /// MayModifySemantics argument is true, then the cleanups is allowed to
 184   /// modify how the code behaves.
 185   ///
 186   std::unique_ptr<Module> performFinalCleanups(std::unique_ptr<Module> M,
 187                                                bool MayModifySemantics = false);
 188
 189   /// Given a module, extract up to one loop from it into a new function. This
 190   /// returns null if there are no extractable loops in the program or if the
 191   /// loop extractor crashes.
 192   std::unique_ptr<Module> extractLoop(Module *M);
 193
 194   /// Extract all but the specified basic blocks into their own functions. The
 195   /// only detail is that M is actually a module cloned from the one the BBs are
 196   /// in, so some mapping needs to be performed. If this operation fails for
 197   /// some reason (ie the implementation is buggy), this function should return
 198   /// null, otherwise it returns a new Module.
 199   std::unique_ptr<Module>
 200   extractMappedBlocksFromModule(const std::vector<BasicBlock *> &BBs,
 201                                 Module *M);
 202
 203   /// Carefully run the specified set of pass on the specified/ module,
 204   /// returning the transformed module on success, or a null pointer on failure.
 205   std::unique_ptr<Module> runPassesOn(Module *M,
 206                                       const std::vector<std::string> &Passes,
 207                                       ArrayRef<std::string> ExtraArgs = {});
 208
 209   /// runPasses - Run the specified passes on Program, outputting a bitcode
 210   /// file and writting the filename into OutputFile if successful.  If the
 211   /// optimizations fail for some reason (optimizer crashes), return true,
 212   /// otherwise return false.  If DeleteOutput is set to true, the bitcode is
 213   /// deleted on success, and the filename string is undefined.  This prints to
 214   /// outs() a single line message indicating whether compilation was successful
 215   /// or failed, unless Quiet is set.  ExtraArgs specifies additional arguments
 216   /// to pass to the child bugpoint instance.
 217   ///
 218   bool runPasses(Module &Program, const std::vector<std::string> &PassesToRun,
 219                  std::string &OutputFilename, bool DeleteOutput = false,
 220                  bool Quiet = false,
 221                  ArrayRef<std::string> ExtraArgs = {}) const;
 222
 223   /// runPasses - Just like the method above, but this just returns true or
 224   /// false indicating whether or not the optimizer crashed on the specified
 225   /// input (true = crashed).  Does not produce any output.
 226   ///
 227   bool runPasses(Module &M, const std::vector<std::string> &PassesToRun) const {
 228     std::string Filename;
 229     return runPasses(M, PassesToRun, Filename, true);
 230   }
 231
 232   /// Take the specified pass list and create different combinations of passes
 233   /// to compile the program with. Compile the program with each set and mark
 234   /// test to see if it compiled correctly. If the passes compiled correctly
 235   /// output nothing and rearrange the passes into a new order. If the passes
 236   /// did not compile correctly, output the command required to recreate the
 237   /// failure.
 238   Error runManyPasses(const std::vector<std::string> &AllPasses);
 239
 240   /// This writes the current "Program" to the named bitcode file.  If an error
 241   /// occurs, true is returned.
 242   bool writeProgramToFile(const std::string &Filename, const Module &M) const;
 243   bool writeProgramToFile(const std::string &Filename, int FD,
 244                           const Module &M) const;
 245   bool writeProgramToFile(int FD, const Module &M) const;
 246
 247 private:
 248   /// initializeExecutionEnvironment - This method is used to set up the
 249   /// environment for executing LLVM programs.
 250   ///
 251   Error initializeExecutionEnvironment();
 252 };
 253
 254 struct DiscardTemp {
 255   sys::fs::TempFile &File;
 256   ~DiscardTemp();
 257 };
 258
 259 ///  Given a bitcode or assembly input filename, parse and return it, or return
 260 ///  null if not possible.
 261 ///
 262 std::unique_ptr<Module> parseInputFile(StringRef InputFilename,
 263                                        LLVMContext &ctxt);
 264
 265 /// getPassesString - Turn a list of passes into a string which indicates the
 266 /// command line options that must be passed to add the passes.
 267 ///
 268 std::string getPassesString(const std::vector<std::string> &Passes);
 269
 270 /// PrintFunctionList - prints out list of problematic functions
 271 ///
 272 void PrintFunctionList(const std::vector<Function *> &Funcs);
 273
 274 /// PrintGlobalVariableList - prints out list of problematic global variables
 275 ///
 276 void PrintGlobalVariableList(const std::vector<GlobalVariable *> &GVs);
 277
 278 // DeleteGlobalInitializer - "Remove" the global variable by deleting its
 279 // initializer, making it external.
 280 //
 281 void DeleteGlobalInitializer(GlobalVariable *GV);
 282
 283 // DeleteFunctionBody - "Remove" the function by deleting all of it's basic
 284 // blocks, making it external.
 285 //
 286 void DeleteFunctionBody(Function *F);
 287
 288 /// Given a module and a list of functions in the module, split the functions
 289 /// OUT of the specified module, and place them in the new module.
 290 std::unique_ptr<Module>
 291 SplitFunctionsOutOfModule(Module *M, const std::vector<Function *> &F,
 292                           ValueToValueMapTy &VMap);
 293
 294 } // End llvm namespace
 295
 296 #endif