xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-dis/llvm-dis.cpp (revision 1f1e2261e341e6ca6862f82261066ef1705f0a7a)
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::OptionCategory DisCategory("Disassembler Options");
39 
40 static cl::list<std::string> InputFilenames(cl::Positional, cl::ZeroOrMore,
41                                             cl::desc("[input bitcode]..."),
42                                             cl::cat(DisCategory));
43 
44 static cl::opt<std::string> OutputFilename("o",
45                                            cl::desc("Override output filename"),
46                                            cl::value_desc("filename"),
47                                            cl::cat(DisCategory));
48 
49 static cl::opt<bool> Force("f", cl::desc("Enable binary output on terminals"),
50                            cl::cat(DisCategory));
51 
52 static cl::opt<bool> DontPrint("disable-output",
53                                cl::desc("Don't output the .ll file"),
54                                cl::Hidden, cl::cat(DisCategory));
55 
56 static cl::opt<bool>
57     SetImporting("set-importing",
58                  cl::desc("Set lazy loading to pretend to import a module"),
59                  cl::Hidden, cl::cat(DisCategory));
60 
61 static cl::opt<bool>
62     ShowAnnotations("show-annotations",
63                     cl::desc("Add informational comments to the .ll file"),
64                     cl::cat(DisCategory));
65 
66 static cl::opt<bool> PreserveAssemblyUseListOrder(
67     "preserve-ll-uselistorder",
68     cl::desc("Preserve use-list order when writing LLVM assembly."),
69     cl::init(false), cl::Hidden, cl::cat(DisCategory));
70 
71 static cl::opt<bool>
72     MaterializeMetadata("materialize-metadata",
73                         cl::desc("Load module without materializing metadata, "
74                                  "then materialize only the metadata"),
75                         cl::cat(DisCategory));
76 
77 static cl::opt<bool> PrintThinLTOIndexOnly(
78     "print-thinlto-index-only",
79     cl::desc("Only read thinlto index and print the index as LLVM assembly."),
80     cl::init(false), cl::Hidden, cl::cat(DisCategory));
81 
82 namespace {
83 
84 static void printDebugLoc(const DebugLoc &DL, formatted_raw_ostream &OS) {
85   OS << DL.getLine() << ":" << DL.getCol();
86   if (DILocation *IDL = DL.getInlinedAt()) {
87     OS << "@";
88     printDebugLoc(IDL, OS);
89   }
90 }
91 class CommentWriter : public AssemblyAnnotationWriter {
92 public:
93   void emitFunctionAnnot(const Function *F,
94                          formatted_raw_ostream &OS) override {
95     OS << "; [#uses=" << F->getNumUses() << ']';  // Output # uses
96     OS << '\n';
97   }
98   void printInfoComment(const Value &V, formatted_raw_ostream &OS) override {
99     bool Padded = false;
100     if (!V.getType()->isVoidTy()) {
101       OS.PadToColumn(50);
102       Padded = true;
103       // Output # uses and type
104       OS << "; [#uses=" << V.getNumUses() << " type=" << *V.getType() << "]";
105     }
106     if (const Instruction *I = dyn_cast<Instruction>(&V)) {
107       if (const DebugLoc &DL = I->getDebugLoc()) {
108         if (!Padded) {
109           OS.PadToColumn(50);
110           Padded = true;
111           OS << ";";
112         }
113         OS << " [debug line = ";
114         printDebugLoc(DL,OS);
115         OS << "]";
116       }
117       if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I)) {
118         if (!Padded) {
119           OS.PadToColumn(50);
120           OS << ";";
121         }
122         OS << " [debug variable = " << DDI->getVariable()->getName() << "]";
123       }
124       else if (const DbgValueInst *DVI = dyn_cast<DbgValueInst>(I)) {
125         if (!Padded) {
126           OS.PadToColumn(50);
127           OS << ";";
128         }
129         OS << " [debug variable = " << DVI->getVariable()->getName() << "]";
130       }
131     }
132   }
133 };
134 
135 struct LLVMDisDiagnosticHandler : public DiagnosticHandler {
136   char *Prefix;
137   LLVMDisDiagnosticHandler(char *PrefixPtr) : Prefix(PrefixPtr) {}
138   bool handleDiagnostics(const DiagnosticInfo &DI) override {
139     raw_ostream &OS = errs();
140     OS << Prefix << ": ";
141     switch (DI.getSeverity()) {
142       case DS_Error: WithColor::error(OS); break;
143       case DS_Warning: WithColor::warning(OS); break;
144       case DS_Remark: OS << "remark: "; break;
145       case DS_Note: WithColor::note(OS); break;
146     }
147 
148     DiagnosticPrinterRawOStream DP(OS);
149     DI.print(DP);
150     OS << '\n';
151 
152     if (DI.getSeverity() == DS_Error)
153       exit(1);
154     return true;
155   }
156 };
157 } // end anon namespace
158 
159 static ExitOnError ExitOnErr;
160 
161 int main(int argc, char **argv) {
162   InitLLVM X(argc, argv);
163 
164   ExitOnErr.setBanner(std::string(argv[0]) + ": error: ");
165 
166   cl::HideUnrelatedOptions({&DisCategory, &getColorCategory()});
167   cl::ParseCommandLineOptions(argc, argv, "llvm .bc -> .ll disassembler\n");
168 
169   LLVMContext Context;
170   Context.setDiagnosticHandler(
171       std::make_unique<LLVMDisDiagnosticHandler>(argv[0]));
172 
173   if (InputFilenames.size() < 1) {
174     InputFilenames.push_back("-");
175   } else if (InputFilenames.size() > 1 && !OutputFilename.empty()) {
176     errs()
177         << "error: output file name cannot be set for multiple input files\n";
178     return 1;
179   }
180 
181   for (std::string InputFilename : InputFilenames) {
182     std::unique_ptr<MemoryBuffer> MB = ExitOnErr(
183         errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename)));
184 
185     BitcodeFileContents IF = ExitOnErr(llvm::getBitcodeFileContents(*MB));
186 
187     const size_t N = IF.Mods.size();
188 
189     if (OutputFilename == "-" && N > 1)
190       errs() << "only single module bitcode files can be written to stdout\n";
191 
192     for (size_t I = 0; I < N; ++I) {
193       BitcodeModule MB = IF.Mods[I];
194 
195       std::unique_ptr<Module> M;
196 
197       if (!PrintThinLTOIndexOnly) {
198         M = ExitOnErr(
199             MB.getLazyModule(Context, MaterializeMetadata, SetImporting));
200         if (MaterializeMetadata)
201           ExitOnErr(M->materializeMetadata());
202         else
203           ExitOnErr(M->materializeAll());
204       }
205 
206       BitcodeLTOInfo LTOInfo = ExitOnErr(MB.getLTOInfo());
207       std::unique_ptr<ModuleSummaryIndex> Index;
208       if (LTOInfo.HasSummary)
209         Index = ExitOnErr(MB.getSummary());
210 
211       std::string FinalFilename(OutputFilename);
212 
213       // Just use stdout.  We won't actually print anything on it.
214       if (DontPrint)
215         FinalFilename = "-";
216 
217       if (FinalFilename.empty()) { // Unspecified output, infer it.
218         if (InputFilename == "-") {
219           FinalFilename = "-";
220         } else {
221           StringRef IFN = InputFilename;
222           FinalFilename = (IFN.endswith(".bc") ? IFN.drop_back(3) : IFN).str();
223           if (N > 1)
224             FinalFilename += std::string(".") + std::to_string(I);
225           FinalFilename += ".ll";
226         }
227       } else {
228         if (N > 1)
229           FinalFilename += std::string(".") + std::to_string(I);
230       }
231 
232       std::error_code EC;
233       std::unique_ptr<ToolOutputFile> Out(
234           new ToolOutputFile(FinalFilename, EC, sys::fs::OF_TextWithCRLF));
235       if (EC) {
236         errs() << EC.message() << '\n';
237         return 1;
238       }
239 
240       std::unique_ptr<AssemblyAnnotationWriter> Annotator;
241       if (ShowAnnotations)
242         Annotator.reset(new CommentWriter());
243 
244       // All that llvm-dis does is write the assembly to a file.
245       if (!DontPrint) {
246         if (M)
247           M->print(Out->os(), Annotator.get(), PreserveAssemblyUseListOrder);
248         if (Index)
249           Index->print(Out->os());
250       }
251 
252       // Declare success.
253       Out->keep();
254     }
255   }
256 
257   return 0;
258 }
259