xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-readobj/WasmDumper.cpp (revision 5f757f3ff9144b609b3c433dfd370cc6bdc191ad) 
1  //===-- WasmDumper.cpp - Wasm-specific object file dumper -----------------===//
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 file implements the Wasm-specific dumper for llvm-readobj.
10  //
11  //===----------------------------------------------------------------------===//
12  
13  #include "ObjDumper.h"
14  #include "llvm-readobj.h"
15  #include "llvm/Object/Wasm.h"
16  #include "llvm/Support/ScopedPrinter.h"
17  
18  using namespace llvm;
19  using namespace object;
20  
21  namespace {
22  
23  const EnumEntry<unsigned> WasmSymbolTypes[] = {
24  #define ENUM_ENTRY(X)                                                          \
25    { #X, wasm::WASM_SYMBOL_TYPE_##X }
26      ENUM_ENTRY(FUNCTION), ENUM_ENTRY(DATA), ENUM_ENTRY(GLOBAL),
27      ENUM_ENTRY(SECTION),  ENUM_ENTRY(TAG),  ENUM_ENTRY(TABLE),
28  #undef ENUM_ENTRY
29  };
30  
31  const EnumEntry<uint32_t> WasmSectionTypes[] = {
32  #define ENUM_ENTRY(X)                                                          \
33    { #X, wasm::WASM_SEC_##X }
34      ENUM_ENTRY(CUSTOM),   ENUM_ENTRY(TYPE),      ENUM_ENTRY(IMPORT),
35      ENUM_ENTRY(FUNCTION), ENUM_ENTRY(TABLE),     ENUM_ENTRY(MEMORY),
36      ENUM_ENTRY(GLOBAL),   ENUM_ENTRY(TAG),       ENUM_ENTRY(EXPORT),
37      ENUM_ENTRY(START),    ENUM_ENTRY(ELEM),      ENUM_ENTRY(CODE),
38      ENUM_ENTRY(DATA),     ENUM_ENTRY(DATACOUNT),
39  #undef ENUM_ENTRY
40  };
41  
42  const EnumEntry<unsigned> WasmSymbolFlags[] = {
43  #define ENUM_ENTRY(X)                                                          \
44    { #X, wasm::WASM_SYMBOL_##X }
45    ENUM_ENTRY(BINDING_GLOBAL),
46    ENUM_ENTRY(BINDING_WEAK),
47    ENUM_ENTRY(BINDING_LOCAL),
48    ENUM_ENTRY(VISIBILITY_DEFAULT),
49    ENUM_ENTRY(VISIBILITY_HIDDEN),
50    ENUM_ENTRY(UNDEFINED),
51    ENUM_ENTRY(EXPORTED),
52    ENUM_ENTRY(EXPLICIT_NAME),
53    ENUM_ENTRY(NO_STRIP),
54  #undef ENUM_ENTRY
55  };
56  
57  class WasmDumper : public ObjDumper {
58  public:
59    WasmDumper(const WasmObjectFile *Obj, ScopedPrinter &Writer)
60        : ObjDumper(Writer, Obj->getFileName()), Obj(Obj) {}
61  
62    void printFileHeaders() override;
63    void printSectionHeaders() override;
64    void printRelocations() override;
65    void printUnwindInfo() override { llvm_unreachable("unimplemented"); }
66    void printStackMap() const override { llvm_unreachable("unimplemented"); }
67  
68  protected:
69    void printSymbol(const SymbolRef &Sym);
70    void printRelocation(const SectionRef &Section, const RelocationRef &Reloc);
71  
72  private:
73    void printSymbols(bool ExtraSymInfo) override;
74    void printDynamicSymbols() override { llvm_unreachable("unimplemented"); }
75  
76    const WasmObjectFile *Obj;
77  };
78  
79  void WasmDumper::printFileHeaders() {
80    W.printHex("Version", Obj->getHeader().Version);
81  }
82  
83  void WasmDumper::printRelocation(const SectionRef &Section,
84                                   const RelocationRef &Reloc) {
85    SmallString<64> RelocTypeName;
86    uint64_t RelocType = Reloc.getType();
87    Reloc.getTypeName(RelocTypeName);
88    const wasm::WasmRelocation &WasmReloc = Obj->getWasmRelocation(Reloc);
89  
90    StringRef SymName;
91    symbol_iterator SI = Reloc.getSymbol();
92    if (SI != Obj->symbol_end())
93      SymName = unwrapOrError(Obj->getFileName(), SI->getName());
94  
95    bool HasAddend = wasm::relocTypeHasAddend(static_cast<uint32_t>(RelocType));
96  
97    if (opts::ExpandRelocs) {
98      DictScope Group(W, "Relocation");
99      W.printNumber("Type", RelocTypeName, RelocType);
100      W.printHex("Offset", Reloc.getOffset());
101      if (!SymName.empty())
102        W.printString("Symbol", SymName);
103      else
104        W.printHex("Index", WasmReloc.Index);
105      if (HasAddend)
106        W.printNumber("Addend", WasmReloc.Addend);
107    } else {
108      raw_ostream &OS = W.startLine();
109      OS << W.hex(Reloc.getOffset()) << " " << RelocTypeName << " ";
110      if (!SymName.empty())
111        OS << SymName;
112      else
113        OS << WasmReloc.Index;
114      if (HasAddend)
115        OS << " " << WasmReloc.Addend;
116      OS << "\n";
117    }
118  }
119  
120  void WasmDumper::printRelocations() {
121    ListScope D(W, "Relocations");
122  
123    int SectionNumber = 0;
124    for (const SectionRef &Section : Obj->sections()) {
125      bool PrintedGroup = false;
126      StringRef Name = unwrapOrError(Obj->getFileName(), Section.getName());
127  
128      ++SectionNumber;
129  
130      for (const RelocationRef &Reloc : Section.relocations()) {
131        if (!PrintedGroup) {
132          W.startLine() << "Section (" << SectionNumber << ") " << Name << " {\n";
133          W.indent();
134          PrintedGroup = true;
135        }
136  
137        printRelocation(Section, Reloc);
138      }
139  
140      if (PrintedGroup) {
141        W.unindent();
142        W.startLine() << "}\n";
143      }
144    }
145  }
146  
147  void WasmDumper::printSymbols(bool /*ExtraSymInfo*/) {
148    ListScope Group(W, "Symbols");
149  
150    for (const SymbolRef &Symbol : Obj->symbols())
151      printSymbol(Symbol);
152  }
153  
154  void WasmDumper::printSectionHeaders() {
155    ListScope Group(W, "Sections");
156    for (const SectionRef &Section : Obj->sections()) {
157      const WasmSection &WasmSec = Obj->getWasmSection(Section);
158      DictScope SectionD(W, "Section");
159      W.printEnum("Type", WasmSec.Type, ArrayRef(WasmSectionTypes));
160      W.printNumber("Size", static_cast<uint64_t>(WasmSec.Content.size()));
161      W.printNumber("Offset", WasmSec.Offset);
162      switch (WasmSec.Type) {
163      case wasm::WASM_SEC_CUSTOM:
164        W.printString("Name", WasmSec.Name);
165        if (WasmSec.Name == "linking") {
166          const wasm::WasmLinkingData &LinkingData = Obj->linkingData();
167          if (!LinkingData.InitFunctions.empty()) {
168            ListScope Group(W, "InitFunctions");
169            for (const wasm::WasmInitFunc &F : LinkingData.InitFunctions)
170              W.startLine() << F.Symbol << " (priority=" << F.Priority << ")\n";
171          }
172        }
173        break;
174      case wasm::WASM_SEC_DATA: {
175        ListScope Group(W, "Segments");
176        for (const WasmSegment &Segment : Obj->dataSegments()) {
177          const wasm::WasmDataSegment &Seg = Segment.Data;
178          DictScope Group(W, "Segment");
179          if (!Seg.Name.empty())
180            W.printString("Name", Seg.Name);
181          W.printNumber("Size", static_cast<uint64_t>(Seg.Content.size()));
182          if (Seg.Offset.Extended)
183            llvm_unreachable("extended const exprs not supported");
184          else if (Seg.Offset.Inst.Opcode == wasm::WASM_OPCODE_I32_CONST)
185            W.printNumber("Offset", Seg.Offset.Inst.Value.Int32);
186          else if (Seg.Offset.Inst.Opcode == wasm::WASM_OPCODE_I64_CONST)
187            W.printNumber("Offset", Seg.Offset.Inst.Value.Int64);
188          else if (Seg.Offset.Inst.Opcode == wasm::WASM_OPCODE_GLOBAL_GET) {
189            ListScope Group(W, "Offset");
190            W.printNumber("Global", Seg.Offset.Inst.Value.Global);
191          } else
192            llvm_unreachable("unknown init expr opcode");
193        }
194        break;
195      }
196      case wasm::WASM_SEC_MEMORY:
197        ListScope Group(W, "Memories");
198        for (const wasm::WasmLimits &Memory : Obj->memories()) {
199          DictScope Group(W, "Memory");
200          W.printNumber("MinPages", Memory.Minimum);
201          if (Memory.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX) {
202            W.printNumber("MaxPages", WasmSec.Offset);
203          }
204        }
205        break;
206      }
207  
208      if (opts::SectionRelocations) {
209        ListScope D(W, "Relocations");
210        for (const RelocationRef &Reloc : Section.relocations())
211          printRelocation(Section, Reloc);
212      }
213  
214      if (opts::SectionData) {
215        W.printBinaryBlock("SectionData", WasmSec.Content);
216      }
217    }
218  }
219  
220  void WasmDumper::printSymbol(const SymbolRef &Sym) {
221    DictScope D(W, "Symbol");
222    WasmSymbol Symbol = Obj->getWasmSymbol(Sym.getRawDataRefImpl());
223    W.printString("Name", Symbol.Info.Name);
224    W.printEnum("Type", Symbol.Info.Kind, ArrayRef(WasmSymbolTypes));
225    W.printFlags("Flags", Symbol.Info.Flags, ArrayRef(WasmSymbolFlags));
226  
227    if (Symbol.Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) {
228      if (Symbol.Info.ImportName) {
229        W.printString("ImportName", *Symbol.Info.ImportName);
230      }
231      if (Symbol.Info.ImportModule) {
232        W.printString("ImportModule", *Symbol.Info.ImportModule);
233      }
234    }
235    if (Symbol.Info.Kind != wasm::WASM_SYMBOL_TYPE_DATA) {
236      W.printHex("ElementIndex", Symbol.Info.ElementIndex);
237    } else if (!(Symbol.Info.Flags & wasm::WASM_SYMBOL_UNDEFINED)) {
238      W.printHex("Offset", Symbol.Info.DataRef.Offset);
239      W.printHex("Segment", Symbol.Info.DataRef.Segment);
240      W.printHex("Size", Symbol.Info.DataRef.Size);
241    }
242  }
243  
244  } // namespace
245  
246  namespace llvm {
247  
248  std::unique_ptr<ObjDumper> createWasmDumper(const object::WasmObjectFile &Obj,
249                                              ScopedPrinter &Writer) {
250    return std::make_unique<WasmDumper>(&Obj, Writer);
251  }
252  
253  } // namespace llvm
254