BugDriver.cpp revision 53bd1b9de74247acae27328cef95bd3888f6cd4d
1//===- BugDriver.cpp - Top-Level BugPoint class implementation ------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source 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 "llvm/Linker.h" 18#include "llvm/Module.h" 19#include "llvm/Pass.h" 20#include "llvm/Assembly/Parser.h" 21#include "llvm/Bytecode/Reader.h" 22#include "llvm/Support/ToolRunner.h" 23#include "llvm/Support/CommandLine.h" 24#include "llvm/Support/FileUtilities.h" 25#include <iostream> 26#include <memory> 27 28using namespace llvm; 29 30// Anonymous namespace to define command line options for debugging. 31// 32namespace { 33 // Output - The user can specify a file containing the expected output of the 34 // program. If this filename is set, it is used as the reference diff source, 35 // otherwise the raw input run through an interpreter is used as the reference 36 // source. 37 // 38 cl::opt<std::string> 39 OutputFile("output", cl::desc("Specify a reference program output " 40 "(for miscompilation detection)")); 41} 42 43/// setNewProgram - If we reduce or update the program somehow, call this method 44/// to update bugdriver with it. This deletes the old module and sets the 45/// specified one as the current program. 46void BugDriver::setNewProgram(Module *M) { 47 delete Program; 48 Program = M; 49} 50 51 52/// getPassesString - Turn a list of passes into a string which indicates the 53/// command line options that must be passed to add the passes. 54/// 55std::string llvm::getPassesString(const std::vector<const PassInfo*> &Passes) { 56 std::string Result; 57 for (unsigned i = 0, e = Passes.size(); i != e; ++i) { 58 if (i) Result += " "; 59 Result += "-"; 60 Result += Passes[i]->getPassArgument(); 61 } 62 return Result; 63} 64 65BugDriver::BugDriver(const char *toolname, bool as_child) 66 : ToolName(toolname), ReferenceOutputFile(OutputFile), 67 Program(0), Interpreter(0), cbe(0), gcc(0), run_as_child(as_child) {} 68 69 70/// ParseInputFile - Given a bytecode or assembly input filename, parse and 71/// return it, or return null if not possible. 72/// 73Module *llvm::ParseInputFile(const std::string &InputFilename) { 74 Module *Result = 0; 75 try { 76 Result = ParseBytecodeFile(InputFilename); 77 if (!Result && !(Result = ParseAssemblyFile(InputFilename))){ 78 std::cerr << "bugpoint: could not read input file '" 79 << InputFilename << "'!\n"; 80 } 81 } catch (const ParseException &E) { 82 std::cerr << "bugpoint: " << E.getMessage() << '\n'; 83 Result = 0; 84 } 85 return Result; 86} 87 88// This method takes the specified list of LLVM input files, attempts to load 89// them, either as assembly or bytecode, then link them together. It returns 90// true on failure (if, for example, an input bytecode file could not be 91// parsed), and false on success. 92// 93bool BugDriver::addSources(const std::vector<std::string> &Filenames) { 94 assert(Program == 0 && "Cannot call addSources multiple times!"); 95 assert(!Filenames.empty() && "Must specify at least on input filename!"); 96 97 try { 98 // Load the first input file. 99 Program = ParseInputFile(Filenames[0]); 100 if (Program == 0) return true; 101 if (!run_as_child) 102 std::cout << "Read input file : '" << Filenames[0] << "'\n"; 103 104 for (unsigned i = 1, e = Filenames.size(); i != e; ++i) { 105 std::auto_ptr<Module> M(ParseInputFile(Filenames[i])); 106 if (M.get() == 0) return true; 107 108 if (!run_as_child) 109 std::cout << "Linking in input file: '" << Filenames[i] << "'\n"; 110 std::string ErrorMessage; 111 if (Linker::LinkModules(Program, M.get(), &ErrorMessage)) { 112 std::cerr << ToolName << ": error linking in '" << Filenames[i] << "': " 113 << ErrorMessage << '\n'; 114 return true; 115 } 116 } 117 } catch (const std::string &Error) { 118 std::cerr << ToolName << ": error reading input '" << Error << "'\n"; 119 return true; 120 } 121 122 if (!run_as_child) 123 std::cout << "*** All input ok\n"; 124 125 // All input files read successfully! 126 return false; 127} 128 129 130 131/// run - The top level method that is invoked after all of the instance 132/// variables are set up from command line arguments. 133/// 134bool BugDriver::run() { 135 // The first thing to do is determine if we're running as a child. If we are, 136 // then what to do is very narrow. This form of invocation is only called 137 // from the runPasses method to actually run those passes in a child process. 138 if (run_as_child) { 139 // Execute the passes 140 return runPassesAsChild(PassesToRun); 141 } 142 143 // If we're not running as a child, the first thing that we must do is 144 // determine what the problem is. Does the optimization series crash the 145 // compiler, or does it produce illegal code? We make the top-level 146 // decision by trying to run all of the passes on the the input program, 147 // which should generate a bytecode file. If it does generate a bytecode 148 // file, then we know the compiler didn't crash, so try to diagnose a 149 // miscompilation. 150 if (!PassesToRun.empty()) { 151 std::cout << "Running selected passes on program to test for crash: "; 152 if (runPasses(PassesToRun)) 153 return debugOptimizerCrash(); 154 } 155 156 // Set up the execution environment, selecting a method to run LLVM bytecode. 157 if (initializeExecutionEnvironment()) return true; 158 159 // Test to see if we have a code generator crash. 160 std::cout << "Running the code generator to test for a crash: "; 161 try { 162 compileProgram(Program); 163 std::cout << '\n'; 164 } catch (ToolExecutionError &TEE) { 165 std::cout << TEE.what(); 166 return debugCodeGeneratorCrash(); 167 } 168 169 170 // Run the raw input to see where we are coming from. If a reference output 171 // was specified, make sure that the raw output matches it. If not, it's a 172 // problem in the front-end or the code generator. 173 // 174 bool CreatedOutput = false; 175 if (ReferenceOutputFile.empty()) { 176 std::cout << "Generating reference output from raw program: "; 177 try { 178 ReferenceOutputFile = executeProgramWithCBE("bugpoint.reference.out"); 179 CreatedOutput = true; 180 std::cout << "Reference output is: " << ReferenceOutputFile << '\n'; 181 } catch (ToolExecutionError &TEE) { 182 std::cerr << TEE.what(); 183 if (Interpreter != cbe) { 184 std::cerr << "*** There is a bug running the C backend. Either debug" 185 << " it (use the -run-cbe bugpoint option), or fix the error" 186 << " some other way.\n"; 187 return 1; 188 } 189 return debugCodeGeneratorCrash(); 190 } 191 } 192 193 // Make sure the reference output file gets deleted on exit from this 194 // function, if appropriate. 195 sys::Path ROF(ReferenceOutputFile); 196 FileRemover RemoverInstance(ROF, CreatedOutput); 197 198 // Diff the output of the raw program against the reference output. If it 199 // matches, then we have a miscompilation bug. 200 std::cout << "*** Checking the code generator...\n"; 201 try { 202 if (!diffProgram()) { 203 std::cout << "\n*** Debugging miscompilation!\n"; 204 return debugMiscompilation(); 205 } 206 } catch (ToolExecutionError &TEE) { 207 std::cerr << TEE.what(); 208 return debugCodeGeneratorCrash(); 209 } 210 211 std::cout << "\n*** Input program does not match reference diff!\n"; 212 std::cout << "Debugging code generator problem!\n"; 213 try { 214 return debugCodeGenerator(); 215 } catch (ToolExecutionError &TEE) { 216 std::cerr << TEE.what(); 217 return debugCodeGeneratorCrash(); 218 } 219} 220 221void llvm::PrintFunctionList(const std::vector<Function*> &Funcs) { 222 unsigned NumPrint = Funcs.size(); 223 if (NumPrint > 10) NumPrint = 10; 224 for (unsigned i = 0; i != NumPrint; ++i) 225 std::cout << " " << Funcs[i]->getName(); 226 if (NumPrint < Funcs.size()) 227 std::cout << "... <" << Funcs.size() << " total>"; 228 std::cout << std::flush; 229} 230