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/Type.h"
  27 #include "llvm/Support/CommandLine.h"
  28 #include "llvm/Support/Error.h"
  29 #include "llvm/Support/FileSystem.h"
  30 #include "llvm/Support/FormattedStream.h"
  31 #include "llvm/Support/InitLLVM.h"
  32 #include "llvm/Support/MemoryBuffer.h"
  33 #include "llvm/Support/ToolOutputFile.h"
  34 #include "llvm/Support/WithColor.h"
  35 #include <system_error>
  36 using namespace llvm;
  37
  38 static cl::opt<std::string>
  39 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
  40
  41 static cl::opt<std::string>
  42 OutputFilename("o", cl::desc("Override output filename"),
  43                cl::value_desc("filename"));
  44
  45 static cl::opt<bool>
  46 Force("f", cl::desc("Enable binary output on terminals"));
  47
  48 static cl::opt<bool>
  49 DontPrint("disable-output", cl::desc("Don't output the .ll file"), cl::Hidden);
  50
  51 static cl::opt<bool>
  52     SetImporting("set-importing",
  53                  cl::desc("Set lazy loading to pretend to import a module"),
  54                  cl::Hidden);
  55
  56 static cl::opt<bool>
  57     ShowAnnotations("show-annotations",
  58                     cl::desc("Add informational comments to the .ll file"));
  59
  60 static cl::opt<bool> PreserveAssemblyUseListOrder(
  61     "preserve-ll-uselistorder",
  62     cl::desc("Preserve use-list order when writing LLVM assembly."),
  63     cl::init(false), cl::Hidden);
  64
  65 static cl::opt<bool>
  66     MaterializeMetadata("materialize-metadata",
  67                         cl::desc("Load module without materializing metadata, "
  68                                  "then materialize only the metadata"));
  69
  70 namespace {
  71
  72 static void printDebugLoc(const DebugLoc &DL, formatted_raw_ostream &OS) {
  73   OS << DL.getLine() << ":" << DL.getCol();
  74   if (DILocation *IDL = DL.getInlinedAt()) {
  75     OS << "@";
  76     printDebugLoc(IDL, OS);
  77   }
  78 }
  79 class CommentWriter : public AssemblyAnnotationWriter {
  80 public:
  81   void emitFunctionAnnot(const Function *F,
  82                          formatted_raw_ostream &OS) override {
  83     OS << "; [#uses=" << F->getNumUses() << ']';  // Output # uses
  84     OS << '\n';
  85   }
  86   void printInfoComment(const Value &V, formatted_raw_ostream &OS) override {
  87     bool Padded = false;
  88     if (!V.getType()->isVoidTy()) {
  89       OS.PadToColumn(50);
  90       Padded = true;
  91       // Output # uses and type
  92       OS << "; [#uses=" << V.getNumUses() << " type=" << *V.getType() << "]";
  93     }
  94     if (const Instruction *I = dyn_cast<Instruction>(&V)) {
  95       if (const DebugLoc &DL = I->getDebugLoc()) {
  96         if (!Padded) {
  97           OS.PadToColumn(50);
  98           Padded = true;
  99           OS << ";";
 100         }
 101         OS << " [debug line = ";
 102         printDebugLoc(DL,OS);
 103         OS << "]";
 104       }
 105       if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I)) {
 106         if (!Padded) {
 107           OS.PadToColumn(50);
 108           OS << ";";
 109         }
 110         OS << " [debug variable = " << DDI->getVariable()->getName() << "]";
 111       }
 112       else if (const DbgValueInst *DVI = dyn_cast<DbgValueInst>(I)) {
 113         if (!Padded) {
 114           OS.PadToColumn(50);
 115           OS << ";";
 116         }
 117         OS << " [debug variable = " << DVI->getVariable()->getName() << "]";
 118       }
 119     }
 120   }
 121 };
 122
 123 struct LLVMDisDiagnosticHandler : public DiagnosticHandler {
 124   char *Prefix;
 125   LLVMDisDiagnosticHandler(char *PrefixPtr) : Prefix(PrefixPtr) {}
 126   bool handleDiagnostics(const DiagnosticInfo &DI) override {
 127     raw_ostream &OS = errs();
 128     OS << Prefix << ": ";
 129     switch (DI.getSeverity()) {
 130       case DS_Error: WithColor::error(OS); break;
 131       case DS_Warning: WithColor::warning(OS); break;
 132       case DS_Remark: OS << "remark: "; break;
 133       case DS_Note: WithColor::note(OS); break;
 134     }
 135
 136     DiagnosticPrinterRawOStream DP(OS);
 137     DI.print(DP);
 138     OS << '\n';
 139
 140     if (DI.getSeverity() == DS_Error)
 141       exit(1);
 142     return true;
 143   }
 144 };
 145 } // end anon namespace
 146
 147 static ExitOnError ExitOnErr;
 148
 149 int main(int argc, char **argv) {
 150   InitLLVM X(argc, argv);
 151
 152   ExitOnErr.setBanner(std::string(argv[0]) + ": error: ");
 153
 154   LLVMContext Context;
 155   Context.setDiagnosticHandler(
 156       std::make_unique<LLVMDisDiagnosticHandler>(argv[0]));
 157   cl::ParseCommandLineOptions(argc, argv, "llvm .bc -> .ll disassembler\n");
 158
 159   std::unique_ptr<MemoryBuffer> MB =
 160       ExitOnErr(errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename)));
 161   std::unique_ptr<Module> M = ExitOnErr(getLazyBitcodeModule(
 162       *MB, Context, /*ShouldLazyLoadMetadata=*/true, SetImporting));
 163   if (MaterializeMetadata)
 164     ExitOnErr(M->materializeMetadata());
 165   else
 166     ExitOnErr(M->materializeAll());
 167
 168   BitcodeLTOInfo LTOInfo = ExitOnErr(getBitcodeLTOInfo(*MB));
 169   std::unique_ptr<ModuleSummaryIndex> Index;
 170   if (LTOInfo.HasSummary)
 171     Index = ExitOnErr(getModuleSummaryIndex(*MB));
 172
 173   // Just use stdout.  We won't actually print anything on it.
 174   if (DontPrint)
 175     OutputFilename = "-";
 176
 177   if (OutputFilename.empty()) { // Unspecified output, infer it.
 178     if (InputFilename == "-") {
 179       OutputFilename = "-";
 180     } else {
 181       StringRef IFN = InputFilename;
 182       OutputFilename = (IFN.endswith(".bc") ? IFN.drop_back(3) : IFN).str();
 183       OutputFilename += ".ll";
 184     }
 185   }
 186
 187   std::error_code EC;
 188   std::unique_ptr<ToolOutputFile> Out(
 189       new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None));
 190   if (EC) {
 191     errs() << EC.message() << '\n';
 192     return 1;
 193   }
 194
 195   std::unique_ptr<AssemblyAnnotationWriter> Annotator;
 196   if (ShowAnnotations)
 197     Annotator.reset(new CommentWriter());
 198
 199   // All that llvm-dis does is write the assembly to a file.
 200   if (!DontPrint) {
 201     M->print(Out->os(), Annotator.get(), PreserveAssemblyUseListOrder);
 202     if (Index)
 203       Index->print(Out->os());
 204   }
 205
 206   // Declare success.
 207   Out->keep();
 208
 209   return 0;
 210 }