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 "Error.h"
14#include "ObjDumper.h"
15#include "llvm-readobj.h"
16#include "llvm/Object/Wasm.h"
17#include "llvm/Support/ScopedPrinter.h"
18
19using namespace llvm;
20using namespace object;
21
22namespace {
23
24static const EnumEntry<unsigned> WasmSymbolTypes[] = {
25#define ENUM_ENTRY(X)                                                          \
26  { #X, wasm::WASM_SYMBOL_TYPE_##X }
27    ENUM_ENTRY(FUNCTION), ENUM_ENTRY(DATA),  ENUM_ENTRY(GLOBAL),
28    ENUM_ENTRY(SECTION),  ENUM_ENTRY(EVENT),
29#undef ENUM_ENTRY
30};
31
32static const EnumEntry<uint32_t> WasmSectionTypes[] = {
33#define ENUM_ENTRY(X)                                                          \
34  { #X, wasm::WASM_SEC_##X }
35    ENUM_ENTRY(CUSTOM),   ENUM_ENTRY(TYPE),      ENUM_ENTRY(IMPORT),
36    ENUM_ENTRY(FUNCTION), ENUM_ENTRY(TABLE),     ENUM_ENTRY(MEMORY),
37    ENUM_ENTRY(GLOBAL),   ENUM_ENTRY(EVENT),     ENUM_ENTRY(EXPORT),
38    ENUM_ENTRY(START),    ENUM_ENTRY(ELEM),      ENUM_ENTRY(CODE),
39    ENUM_ENTRY(DATA),     ENUM_ENTRY(DATACOUNT),
40#undef ENUM_ENTRY
41};
42
43static const EnumEntry<unsigned> WasmSymbolFlags[] = {
44#define ENUM_ENTRY(X)                                                          \
45  { #X, wasm::WASM_SYMBOL_##X }
46  ENUM_ENTRY(BINDING_GLOBAL),
47  ENUM_ENTRY(BINDING_WEAK),
48  ENUM_ENTRY(BINDING_LOCAL),
49  ENUM_ENTRY(VISIBILITY_DEFAULT),
50  ENUM_ENTRY(VISIBILITY_HIDDEN),
51  ENUM_ENTRY(UNDEFINED),
52  ENUM_ENTRY(EXPORTED),
53  ENUM_ENTRY(EXPLICIT_NAME),
54  ENUM_ENTRY(NO_STRIP),
55#undef ENUM_ENTRY
56};
57
58class WasmDumper : public ObjDumper {
59public:
60  WasmDumper(const WasmObjectFile *Obj, ScopedPrinter &Writer)
61      : ObjDumper(Writer), Obj(Obj) {}
62
63  void printFileHeaders() override;
64  void printSectionHeaders() override;
65  void printRelocations() override;
66  void printUnwindInfo() override { llvm_unreachable("unimplemented"); }
67  void printStackMap() const override { llvm_unreachable("unimplemented"); }
68
69protected:
70  void printSymbol(const SymbolRef &Sym);
71  void printRelocation(const SectionRef &Section, const RelocationRef &Reloc);
72
73private:
74  void printSymbols() override;
75  void printDynamicSymbols() override { llvm_unreachable("unimplemented"); }
76
77  const WasmObjectFile *Obj;
78};
79
80void WasmDumper::printFileHeaders() {
81  W.printHex("Version", Obj->getHeader().Version);
82}
83
84void WasmDumper::printRelocation(const SectionRef &Section,
85                                 const RelocationRef &Reloc) {
86  SmallString<64> RelocTypeName;
87  uint64_t RelocType = Reloc.getType();
88  Reloc.getTypeName(RelocTypeName);
89  const wasm::WasmRelocation &WasmReloc = Obj->getWasmRelocation(Reloc);
90
91  StringRef SymName;
92  symbol_iterator SI = Reloc.getSymbol();
93  if (SI != Obj->symbol_end())
94    SymName = unwrapOrError(Obj->getFileName(), SI->getName());
95
96  bool HasAddend = wasm::relocTypeHasAddend(static_cast<uint32_t>(RelocType));
97
98  if (opts::ExpandRelocs) {
99    DictScope Group(W, "Relocation");
100    W.printNumber("Type", RelocTypeName, RelocType);
101    W.printHex("Offset", Reloc.getOffset());
102    if (!SymName.empty())
103      W.printString("Symbol", SymName);
104    else
105      W.printHex("Index", WasmReloc.Index);
106    if (HasAddend)
107      W.printNumber("Addend", WasmReloc.Addend);
108  } else {
109    raw_ostream &OS = W.startLine();
110    OS << W.hex(Reloc.getOffset()) << " " << RelocTypeName << " ";
111    if (!SymName.empty())
112      OS << SymName;
113    else
114      OS << WasmReloc.Index;
115    if (HasAddend)
116      OS << " " << WasmReloc.Addend;
117    OS << "\n";
118  }
119}
120
121void WasmDumper::printRelocations() {
122  ListScope D(W, "Relocations");
123
124  int SectionNumber = 0;
125  for (const SectionRef &Section : Obj->sections()) {
126    bool PrintedGroup = false;
127    StringRef Name = unwrapOrError(Obj->getFileName(), Section.getName());
128
129    ++SectionNumber;
130
131    for (const RelocationRef &Reloc : Section.relocations()) {
132      if (!PrintedGroup) {
133        W.startLine() << "Section (" << SectionNumber << ") " << Name << " {\n";
134        W.indent();
135        PrintedGroup = true;
136      }
137
138      printRelocation(Section, Reloc);
139    }
140
141    if (PrintedGroup) {
142      W.unindent();
143      W.startLine() << "}\n";
144    }
145  }
146}
147
148void WasmDumper::printSymbols() {
149  ListScope Group(W, "Symbols");
150
151  for (const SymbolRef &Symbol : Obj->symbols())
152    printSymbol(Symbol);
153}
154
155void WasmDumper::printSectionHeaders() {
156  ListScope Group(W, "Sections");
157  for (const SectionRef &Section : Obj->sections()) {
158    const WasmSection &WasmSec = Obj->getWasmSection(Section);
159    DictScope SectionD(W, "Section");
160    W.printEnum("Type", WasmSec.Type, makeArrayRef(WasmSectionTypes));
161    W.printNumber("Size", static_cast<uint64_t>(WasmSec.Content.size()));
162    W.printNumber("Offset", WasmSec.Offset);
163    switch (WasmSec.Type) {
164    case wasm::WASM_SEC_CUSTOM:
165      W.printString("Name", WasmSec.Name);
166      if (WasmSec.Name == "linking") {
167        const wasm::WasmLinkingData &LinkingData = Obj->linkingData();
168        if (!LinkingData.InitFunctions.empty()) {
169          ListScope Group(W, "InitFunctions");
170          for (const wasm::WasmInitFunc &F : LinkingData.InitFunctions)
171            W.startLine() << F.Symbol << " (priority=" << F.Priority << ")\n";
172        }
173      }
174      break;
175    case wasm::WASM_SEC_DATA: {
176      ListScope Group(W, "Segments");
177      for (const WasmSegment &Segment : Obj->dataSegments()) {
178        const wasm::WasmDataSegment &Seg = Segment.Data;
179        DictScope Group(W, "Segment");
180        if (!Seg.Name.empty())
181          W.printString("Name", Seg.Name);
182        W.printNumber("Size", static_cast<uint64_t>(Seg.Content.size()));
183        if (Seg.Offset.Opcode == wasm::WASM_OPCODE_I32_CONST)
184          W.printNumber("Offset", Seg.Offset.Value.Int32);
185        else if (Seg.Offset.Opcode == wasm::WASM_OPCODE_I64_CONST)
186          W.printNumber("Offset", Seg.Offset.Value.Int64);
187        else
188          llvm_unreachable("unknown init expr opcode");
189      }
190      break;
191    }
192    case wasm::WASM_SEC_MEMORY:
193      ListScope Group(W, "Memories");
194      for (const wasm::WasmLimits &Memory : Obj->memories()) {
195        DictScope Group(W, "Memory");
196        W.printNumber("InitialPages", Memory.Initial);
197        if (Memory.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX) {
198          W.printNumber("MaxPages", WasmSec.Offset);
199        }
200      }
201      break;
202    }
203
204    if (opts::SectionRelocations) {
205      ListScope D(W, "Relocations");
206      for (const RelocationRef &Reloc : Section.relocations())
207        printRelocation(Section, Reloc);
208    }
209
210    if (opts::SectionData) {
211      W.printBinaryBlock("SectionData", WasmSec.Content);
212    }
213  }
214}
215
216void WasmDumper::printSymbol(const SymbolRef &Sym) {
217  DictScope D(W, "Symbol");
218  WasmSymbol Symbol = Obj->getWasmSymbol(Sym.getRawDataRefImpl());
219  W.printString("Name", Symbol.Info.Name);
220  W.printEnum("Type", Symbol.Info.Kind, makeArrayRef(WasmSymbolTypes));
221  W.printFlags("Flags", Symbol.Info.Flags, makeArrayRef(WasmSymbolFlags));
222
223  if (Symbol.Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) {
224    if (Symbol.Info.ImportName) {
225      W.printString("ImportName", *Symbol.Info.ImportName);
226    }
227    if (Symbol.Info.ImportModule) {
228      W.printString("ImportModule", *Symbol.Info.ImportModule);
229    }
230  }
231  if (Symbol.Info.Kind != wasm::WASM_SYMBOL_TYPE_DATA) {
232    W.printHex("ElementIndex", Symbol.Info.ElementIndex);
233  } else if (!(Symbol.Info.Flags & wasm::WASM_SYMBOL_UNDEFINED)) {
234    W.printHex("Offset", Symbol.Info.DataRef.Offset);
235    W.printHex("Segment", Symbol.Info.DataRef.Segment);
236    W.printHex("Size", Symbol.Info.DataRef.Size);
237  }
238}
239
240} // namespace
241
242namespace llvm {
243
244std::error_code createWasmDumper(const object::ObjectFile *Obj,
245                                 ScopedPrinter &Writer,
246                                 std::unique_ptr<ObjDumper> &Result) {
247  const auto *WasmObj = dyn_cast<WasmObjectFile>(Obj);
248  assert(WasmObj && "createWasmDumper called with non-wasm object");
249
250  Result.reset(new WasmDumper(WasmObj, Writer));
251  return readobj_error::success;
252}
253
254} // namespace llvm
255