llvm/tools/llvm-dis/llvm-dis.cpp

   1 //===-- llvm-dis.cpp - The low-level LLVM disassembler --------------------===//
   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 utility may be invoked in the following manner:
  10 //  llvm-dis [options]      - Read LLVM bitcode from stdin, write asm to stdout
  11 //  llvm-dis [options] x.bc - Read LLVM bitcode from the x.bc file, write asm
  12 //                            to the x.ll file.
  13 //  Options:
  14 //      --help   - Output information about command line switches
  15 //
  16 //===----------------------------------------------------------------------===//
  17
  18 #include "llvm/Bitcode/BitcodeReader.h"
  19 #include "llvm/IR/AssemblyAnnotationWriter.h"
  20 #include "llvm/IR/DebugInfo.h"
  21 #include "llvm/IR/DiagnosticInfo.h"
  22 #include "llvm/IR/DiagnosticPrinter.h"
  23 #include "llvm/IR/IntrinsicInst.h"
  24 #include "llvm/IR/LLVMContext.h"
  25 #include "llvm/IR/Module.h"
  26 #include "llvm/IR/ModuleSummaryIndex.h"
  27 #include "llvm/IR/Type.h"
  28 #include "llvm/Support/CommandLine.h"
  29 #include "llvm/Support/Error.h"
  30 #include "llvm/Support/FileSystem.h"
  31 #include "llvm/Support/FormattedStream.h"
  32 #include "llvm/Support/InitLLVM.h"
  33 #include "llvm/Support/MemoryBuffer.h"
  34 #include "llvm/Support/ToolOutputFile.h"
  35 #include "llvm/Support/WithColor.h"
  36 #include <system_error>
  37 using namespace llvm;
  38
  39 static cl::OptionCategory DisCategory("Disassembler Options");
  40
  41 static cl::list<std::string> InputFilenames(cl::Positional,
  42                                             cl::desc("[input bitcode]..."),
  43                                             cl::cat(DisCategory));
  44
  45 static cl::opt<std::string> OutputFilename("o",
  46                                            cl::desc("Override output filename"),
  47                                            cl::value_desc("filename"),
  48                                            cl::cat(DisCategory));
  49
  50 static cl::opt<bool> Force("f", cl::desc("Enable binary output on terminals"),
  51                            cl::cat(DisCategory));
  52
  53 static cl::opt<bool> DontPrint("disable-output",
  54                                cl::desc("Don't output the .ll file"),
  55                                cl::Hidden, cl::cat(DisCategory));
  56
  57 static cl::opt<bool>
  58     SetImporting("set-importing",
  59                  cl::desc("Set lazy loading to pretend to import a module"),
  60                  cl::Hidden, cl::cat(DisCategory));
  61
  62 static cl::opt<bool>
  63     ShowAnnotations("show-annotations",
  64                     cl::desc("Add informational comments to the .ll file"),
  65                     cl::cat(DisCategory));
  66
  67 static cl::opt<bool> PreserveAssemblyUseListOrder(
  68     "preserve-ll-uselistorder",
  69     cl::desc("Preserve use-list order when writing LLVM assembly."),
  70     cl::init(false), cl::Hidden, cl::cat(DisCategory));
  71
  72 static cl::opt<bool>
  73     MaterializeMetadata("materialize-metadata",
  74                         cl::desc("Load module without materializing metadata, "
  75                                  "then materialize only the metadata"),
  76                         cl::cat(DisCategory));
  77
  78 static cl::opt<bool> PrintThinLTOIndexOnly(
  79     "print-thinlto-index-only",
  80     cl::desc("Only read thinlto index and print the index as LLVM assembly."),
  81     cl::init(false), cl::Hidden, cl::cat(DisCategory));
  82
  83 namespace {
  84
  85 static void printDebugLoc(const DebugLoc &DL, formatted_raw_ostream &OS) {
  86   OS << DL.getLine() << ":" << DL.getCol();
  87   if (DILocation *IDL = DL.getInlinedAt()) {
  88     OS << "@";
  89     printDebugLoc(IDL, OS);
  90   }
  91 }
  92 class CommentWriter : public AssemblyAnnotationWriter {
  93 public:
  94   void emitFunctionAnnot(const Function *F,
  95                          formatted_raw_ostream &OS) override {
  96     OS << "; [#uses=" << F->getNumUses() << ']';  // Output # uses
  97     OS << '\n';
  98   }
  99   void printInfoComment(const Value &V, formatted_raw_ostream &OS) override {
 100     bool Padded = false;
 101     if (!V.getType()->isVoidTy()) {
 102       OS.PadToColumn(50);
 103       Padded = true;
 104       // Output # uses and type
 105       OS << "; [#uses=" << V.getNumUses() << " type=" << *V.getType() << "]";
 106     }
 107     if (const Instruction *I = dyn_cast<Instruction>(&V)) {
 108       if (const DebugLoc &DL = I->getDebugLoc()) {
 109         if (!Padded) {
 110           OS.PadToColumn(50);
 111           Padded = true;
 112           OS << ";";
 113         }
 114         OS << " [debug line = ";
 115         printDebugLoc(DL,OS);
 116         OS << "]";
 117       }
 118       if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I)) {
 119         if (!Padded) {
 120           OS.PadToColumn(50);
 121           OS << ";";
 122         }
 123         OS << " [debug variable = " << DDI->getVariable()->getName() << "]";
 124       }
 125       else if (const DbgValueInst *DVI = dyn_cast<DbgValueInst>(I)) {
 126         if (!Padded) {
 127           OS.PadToColumn(50);
 128           OS << ";";
 129         }
 130         OS << " [debug variable = " << DVI->getVariable()->getName() << "]";
 131       }
 132     }
 133   }
 134 };
 135
 136 struct LLVMDisDiagnosticHandler : public DiagnosticHandler {
 137   char *Prefix;
 138   LLVMDisDiagnosticHandler(char *PrefixPtr) : Prefix(PrefixPtr) {}
 139   bool handleDiagnostics(const DiagnosticInfo &DI) override {
 140     raw_ostream &OS = errs();
 141     OS << Prefix << ": ";
 142     switch (DI.getSeverity()) {
 143       case DS_Error: WithColor::error(OS); break;
 144       case DS_Warning: WithColor::warning(OS); break;
 145       case DS_Remark: OS << "remark: "; break;
 146       case DS_Note: WithColor::note(OS); break;
 147     }
 148
 149     DiagnosticPrinterRawOStream DP(OS);
 150     DI.print(DP);
 151     OS << '\n';
 152
 153     if (DI.getSeverity() == DS_Error)
 154       exit(1);
 155     return true;
 156   }
 157 };
 158 } // end anon namespace
 159
 160 static ExitOnError ExitOnErr;
 161
 162 int main(int argc, char **argv) {
 163   InitLLVM X(argc, argv);
 164
 165   ExitOnErr.setBanner(std::string(argv[0]) + ": error: ");
 166
 167   cl::HideUnrelatedOptions({&DisCategory, &getColorCategory()});
 168   cl::ParseCommandLineOptions(argc, argv, "llvm .bc -> .ll disassembler\n");
 169
 170   LLVMContext Context;
 171   Context.setDiagnosticHandler(
 172       std::make_unique<LLVMDisDiagnosticHandler>(argv[0]));
 173
 174   if (InputFilenames.size() < 1) {
 175     InputFilenames.push_back("-");
 176   } else if (InputFilenames.size() > 1 && !OutputFilename.empty()) {
 177     errs()
 178         << "error: output file name cannot be set for multiple input files\n";
 179     return 1;
 180   }
 181
 182   for (std::string InputFilename : InputFilenames) {
 183     ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
 184         MemoryBuffer::getFileOrSTDIN(InputFilename);
 185     if (std::error_code EC = BufferOrErr.getError()) {
 186       WithColor::error() << InputFilename << ": " << EC.message() << '\n';
 187       return 1;
 188     }
 189     std::unique_ptr<MemoryBuffer> MB = std::move(BufferOrErr.get());
 190
 191     BitcodeFileContents IF = ExitOnErr(llvm::getBitcodeFileContents(*MB));
 192
 193     const size_t N = IF.Mods.size();
 194
 195     if (OutputFilename == "-" && N > 1)
 196       errs() << "only single module bitcode files can be written to stdout\n";
 197
 198     for (size_t I = 0; I < N; ++I) {
 199       BitcodeModule MB = IF.Mods[I];
 200
 201       std::unique_ptr<Module> M;
 202
 203       if (!PrintThinLTOIndexOnly) {
 204         M = ExitOnErr(
 205             MB.getLazyModule(Context, MaterializeMetadata, SetImporting));
 206         if (MaterializeMetadata)
 207           ExitOnErr(M->materializeMetadata());
 208         else
 209           ExitOnErr(M->materializeAll());
 210       }
 211
 212       BitcodeLTOInfo LTOInfo = ExitOnErr(MB.getLTOInfo());
 213       std::unique_ptr<ModuleSummaryIndex> Index;
 214       if (LTOInfo.HasSummary)
 215         Index = ExitOnErr(MB.getSummary());
 216
 217       std::string FinalFilename(OutputFilename);
 218
 219       // Just use stdout.  We won't actually print anything on it.
 220       if (DontPrint)
 221         FinalFilename = "-";
 222
 223       if (FinalFilename.empty()) { // Unspecified output, infer it.
 224         if (InputFilename == "-") {
 225           FinalFilename = "-";
 226         } else {
 227           StringRef IFN = InputFilename;
 228           FinalFilename = (IFN.endswith(".bc") ? IFN.drop_back(3) : IFN).str();
 229           if (N > 1)
 230             FinalFilename += std::string(".") + std::to_string(I);
 231           FinalFilename += ".ll";
 232         }
 233       } else {
 234         if (N > 1)
 235           FinalFilename += std::string(".") + std::to_string(I);
 236       }
 237
 238       std::error_code EC;
 239       std::unique_ptr<ToolOutputFile> Out(
 240           new ToolOutputFile(FinalFilename, EC, sys::fs::OF_TextWithCRLF));
 241       if (EC) {
 242         errs() << EC.message() << '\n';
 243         return 1;
 244       }
 245
 246       std::unique_ptr<AssemblyAnnotationWriter> Annotator;
 247       if (ShowAnnotations)
 248         Annotator.reset(new CommentWriter());
 249
 250       // All that llvm-dis does is write the assembly to a file.
 251       if (!DontPrint) {
 252         if (M)
 253           M->print(Out->os(), Annotator.get(), PreserveAssemblyUseListOrder);
 254         if (Index)
 255           Index->print(Out->os());
 256       }
 257
 258       // Declare success.
 259       Out->keep();
 260     }
 261   }
 262
 263   return 0;
 264 }