tools/bugpoint/bugpoint.cpp

   1 //===- bugpoint.cpp - The LLVM Bugpoint utility ---------------------------===//
   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 program is an automated compiler debugger tool.  It is used to narrow
  10 // down miscompilations and crash problems to a specific pass in the compiler,
  11 // and the specific Module or Function input that is causing the problem.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "BugDriver.h"
  16 #include "ToolRunner.h"
  17 #include "llvm/Config/llvm-config.h"
  18 #include "llvm/IR/LLVMContext.h"
  19 #include "llvm/IR/LegacyPassManager.h"
  20 #include "llvm/IR/LegacyPassNameParser.h"
  21 #include "llvm/LinkAllIR.h"
  22 #include "llvm/LinkAllPasses.h"
  23 #include "llvm/Support/CommandLine.h"
  24 #include "llvm/Support/InitLLVM.h"
  25 #include "llvm/Support/ManagedStatic.h"
  26 #include "llvm/Support/PluginLoader.h"
  27 #include "llvm/Support/PrettyStackTrace.h"
  28 #include "llvm/Support/Process.h"
  29 #include "llvm/Support/TargetSelect.h"
  30 #include "llvm/Support/Valgrind.h"
  31 #include "llvm/Transforms/IPO/AlwaysInliner.h"
  32 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
  33
  34 // Enable this macro to debug bugpoint itself.
  35 //#define DEBUG_BUGPOINT 1
  36
  37 using namespace llvm;
  38
  39 static cl::opt<bool>
  40     FindBugs("find-bugs", cl::desc("Run many different optimization sequences "
  41                                    "on program to find bugs"),
  42              cl::init(false));
  43
  44 static cl::list<std::string>
  45     InputFilenames(cl::Positional, cl::OneOrMore,
  46                    cl::desc("<input llvm ll/bc files>"));
  47
  48 static cl::opt<unsigned> TimeoutValue(
  49     "timeout", cl::init(300), cl::value_desc("seconds"),
  50     cl::desc("Number of seconds program is allowed to run before it "
  51              "is killed (default is 300s), 0 disables timeout"));
  52
  53 static cl::opt<int> MemoryLimit(
  54     "mlimit", cl::init(-1), cl::value_desc("MBytes"),
  55     cl::desc("Maximum amount of memory to use. 0 disables check. Defaults to "
  56              "400MB (800MB under valgrind, 0 with sanitizers)."));
  57
  58 static cl::opt<bool>
  59     UseValgrind("enable-valgrind",
  60                 cl::desc("Run optimizations through valgrind"));
  61
  62 // The AnalysesList is automatically populated with registered Passes by the
  63 // PassNameParser.
  64 //
  65 static cl::list<const PassInfo *, bool, PassNameParser>
  66     PassList(cl::desc("Passes available:"), cl::ZeroOrMore);
  67
  68 static cl::opt<bool>
  69     StandardLinkOpts("std-link-opts",
  70                      cl::desc("Include the standard link time optimizations"));
  71
  72 static cl::opt<bool>
  73     OptLevelO1("O1", cl::desc("Optimization level 1. Identical to 'opt -O1'"));
  74
  75 static cl::opt<bool>
  76     OptLevelO2("O2", cl::desc("Optimization level 2. Identical to 'opt -O2'"));
  77
  78 static cl::opt<bool> OptLevelOs(
  79     "Os",
  80     cl::desc(
  81         "Like -O2 with extra optimizations for size. Similar to clang -Os"));
  82
  83 static cl::opt<bool>
  84 OptLevelOz("Oz",
  85            cl::desc("Like -Os but reduces code size further. Similar to clang -Oz"));
  86
  87 static cl::opt<bool>
  88     OptLevelO3("O3", cl::desc("Optimization level 3. Identical to 'opt -O3'"));
  89
  90 static cl::opt<std::string>
  91     OverrideTriple("mtriple", cl::desc("Override target triple for module"));
  92
  93 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
  94 bool llvm::BugpointIsInterrupted = false;
  95
  96 #ifndef DEBUG_BUGPOINT
  97 static void BugpointInterruptFunction() { BugpointIsInterrupted = true; }
  98 #endif
  99
 100 // Hack to capture a pass list.
 101 namespace {
 102 class AddToDriver : public legacy::FunctionPassManager {
 103   BugDriver &D;
 104
 105 public:
 106   AddToDriver(BugDriver &_D) : FunctionPassManager(nullptr), D(_D) {}
 107
 108   void add(Pass *P) override {
 109     const void *ID = P->getPassID();
 110     const PassInfo *PI = PassRegistry::getPassRegistry()->getPassInfo(ID);
 111     D.addPass(PI->getPassArgument());
 112   }
 113 };
 114 }
 115
 116 // This routine adds optimization passes based on selected optimization level,
 117 // OptLevel.
 118 //
 119 // OptLevel - Optimization Level
 120 static void AddOptimizationPasses(legacy::FunctionPassManager &FPM,
 121                                   unsigned OptLevel,
 122                                   unsigned SizeLevel) {
 123   PassManagerBuilder Builder;
 124   Builder.OptLevel = OptLevel;
 125   Builder.SizeLevel = SizeLevel;
 126
 127   if (OptLevel > 1)
 128     Builder.Inliner = createFunctionInliningPass(OptLevel, SizeLevel, false);
 129   else
 130     Builder.Inliner = createAlwaysInlinerLegacyPass();
 131
 132   Builder.populateFunctionPassManager(FPM);
 133   Builder.populateModulePassManager(FPM);
 134 }
 135
 136 #ifdef LINK_POLLY_INTO_TOOLS
 137 namespace polly {
 138 void initializePollyPasses(llvm::PassRegistry &Registry);
 139 }
 140 #endif
 141
 142 int main(int argc, char **argv) {
 143 #ifndef DEBUG_BUGPOINT
 144   InitLLVM X(argc, argv);
 145 #endif
 146
 147   // Initialize passes
 148   PassRegistry &Registry = *PassRegistry::getPassRegistry();
 149   initializeCore(Registry);
 150   initializeScalarOpts(Registry);
 151   initializeObjCARCOpts(Registry);
 152   initializeVectorization(Registry);
 153   initializeIPO(Registry);
 154   initializeAnalysis(Registry);
 155   initializeTransformUtils(Registry);
 156   initializeInstCombine(Registry);
 157   initializeAggressiveInstCombine(Registry);
 158   initializeInstrumentation(Registry);
 159   initializeTarget(Registry);
 160
 161 #ifdef LINK_POLLY_INTO_TOOLS
 162   polly::initializePollyPasses(Registry);
 163 #endif
 164
 165   if (std::getenv("bar") == (char*) -1) {
 166     InitializeAllTargets();
 167     InitializeAllTargetMCs();
 168     InitializeAllAsmPrinters();
 169     InitializeAllAsmParsers();
 170   }
 171
 172   cl::ParseCommandLineOptions(argc, argv,
 173                               "LLVM automatic testcase reducer. See\nhttp://"
 174                               "llvm.org/cmds/bugpoint.html"
 175                               " for more information.\n");
 176 #ifndef DEBUG_BUGPOINT
 177   sys::SetInterruptFunction(BugpointInterruptFunction);
 178 #endif
 179
 180   LLVMContext Context;
 181   // If we have an override, set it and then track the triple we want Modules
 182   // to use.
 183   if (!OverrideTriple.empty()) {
 184     TargetTriple.setTriple(Triple::normalize(OverrideTriple));
 185     outs() << "Override triple set to '" << TargetTriple.getTriple() << "'\n";
 186   }
 187
 188   if (MemoryLimit < 0) {
 189     // Set the default MemoryLimit.  Be sure to update the flag's description if
 190     // you change this.
 191     if (sys::RunningOnValgrind() || UseValgrind)
 192       MemoryLimit = 800;
 193     else
 194       MemoryLimit = 400;
 195 #if (LLVM_ADDRESS_SANITIZER_BUILD || LLVM_MEMORY_SANITIZER_BUILD ||            \
 196      LLVM_THREAD_SANITIZER_BUILD)
 197     // Starting from kernel 4.9 memory allocated with mmap is counted against
 198     // RLIMIT_DATA. Sanitizers need to allocate tens of terabytes for shadow.
 199     MemoryLimit = 0;
 200 #endif
 201   }
 202
 203   BugDriver D(argv[0], FindBugs, TimeoutValue, MemoryLimit, UseValgrind,
 204               Context);
 205   if (D.addSources(InputFilenames))
 206     return 1;
 207
 208   AddToDriver PM(D);
 209
 210   if (StandardLinkOpts) {
 211     PassManagerBuilder Builder;
 212     Builder.Inliner = createFunctionInliningPass();
 213     Builder.populateLTOPassManager(PM);
 214   }
 215
 216   if (OptLevelO1)
 217     AddOptimizationPasses(PM, 1, 0);
 218   else if (OptLevelO2)
 219     AddOptimizationPasses(PM, 2, 0);
 220   else if (OptLevelO3)
 221     AddOptimizationPasses(PM, 3, 0);
 222   else if (OptLevelOs)
 223     AddOptimizationPasses(PM, 2, 1);
 224   else if (OptLevelOz)
 225     AddOptimizationPasses(PM, 2, 2);
 226
 227   for (const PassInfo *PI : PassList)
 228     D.addPass(PI->getPassArgument());
 229
 230 // Bugpoint has the ability of generating a plethora of core files, so to
 231 // avoid filling up the disk, we prevent it
 232 #ifndef DEBUG_BUGPOINT
 233   sys::Process::PreventCoreFiles();
 234 #endif
 235
 236   if (Error E = D.run()) {
 237     errs() << toString(std::move(E));
 238     return 1;
 239   }
 240   return 0;
 241 }