llvm/tools/llvm-readobj/WasmDumper.cpp

   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() 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() {
 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