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