xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-dis/llvm-dis.cpp (revision a7dea1671b87c07d2d266f836bfa8b58efc7c134)
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_Text));
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 }
211