tools/llvm-readobj/WasmDumper.cpp

   1 //===-- WasmDumper.cpp - Wasm-specific object file dumper -----------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the Wasm-specific dumper for llvm-readobj.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "Error.h"
  15 #include "ObjDumper.h"
  16 #include "llvm-readobj.h"
  17 #include "llvm/Object/Wasm.h"
  18 #include "llvm/Support/ScopedPrinter.h"
  19
  20 using namespace llvm;
  21 using namespace object;
  22
  23 namespace {
  24
  25 static const EnumEntry<unsigned> WasmSymbolTypes[] = {
  26 #define ENUM_ENTRY(X) { #X, wasm::WASM_SYMBOL_TYPE_##X }
  27   ENUM_ENTRY(FUNCTION),
  28   ENUM_ENTRY(DATA),
  29   ENUM_ENTRY(GLOBAL),
  30   ENUM_ENTRY(SECTION),
  31 #undef ENUM_ENTRY
  32 };
  33
  34 static const EnumEntry<uint32_t> WasmSectionTypes[] = {
  35 #define ENUM_ENTRY(X) { #X, wasm::WASM_SEC_##X }
  36   ENUM_ENTRY(CUSTOM),
  37   ENUM_ENTRY(TYPE),
  38   ENUM_ENTRY(IMPORT),
  39   ENUM_ENTRY(FUNCTION),
  40   ENUM_ENTRY(TABLE),
  41   ENUM_ENTRY(MEMORY),
  42   ENUM_ENTRY(GLOBAL),
  43   ENUM_ENTRY(EXPORT),
  44   ENUM_ENTRY(START),
  45   ENUM_ENTRY(ELEM),
  46   ENUM_ENTRY(CODE),
  47   ENUM_ENTRY(DATA),
  48 #undef ENUM_ENTRY
  49 };
  50
  51 class WasmDumper : public ObjDumper {
  52 public:
  53   WasmDumper(const WasmObjectFile *Obj, ScopedPrinter &Writer)
  54       : ObjDumper(Writer), Obj(Obj) {}
  55
  56   void printFileHeaders() override;
  57   void printSections() override;
  58   void printRelocations() override;
  59   void printSymbols() override;
  60   void printDynamicSymbols() override { llvm_unreachable("unimplemented"); }
  61   void printUnwindInfo() override { llvm_unreachable("unimplemented"); }
  62   void printStackMap() const override { llvm_unreachable("unimplemented"); }
  63
  64 protected:
  65   void printSymbol(const SymbolRef &Sym);
  66   void printRelocation(const SectionRef &Section, const RelocationRef &Reloc);
  67
  68 private:
  69   const WasmObjectFile *Obj;
  70 };
  71
  72 void WasmDumper::printFileHeaders() {
  73   W.printHex("Version", Obj->getHeader().Version);
  74 }
  75
  76 void WasmDumper::printRelocation(const SectionRef &Section,
  77                                  const RelocationRef &Reloc) {
  78   SmallString<64> RelocTypeName;
  79   uint64_t RelocType = Reloc.getType();
  80   Reloc.getTypeName(RelocTypeName);
  81   const wasm::WasmRelocation &WasmReloc = Obj->getWasmRelocation(Reloc);
  82
  83   StringRef SymName;
  84   symbol_iterator SI = Reloc.getSymbol();
  85   if (SI != Obj->symbol_end())
  86     SymName = error(SI->getName());
  87
  88   bool HasAddend = false;
  89   switch (RelocType) {
  90   case wasm::R_WEBASSEMBLY_MEMORY_ADDR_LEB:
  91   case wasm::R_WEBASSEMBLY_MEMORY_ADDR_SLEB:
  92   case wasm::R_WEBASSEMBLY_MEMORY_ADDR_I32:
  93   case wasm::R_WEBASSEMBLY_FUNCTION_OFFSET_I32:
  94   case wasm::R_WEBASSEMBLY_SECTION_OFFSET_I32:
  95     HasAddend = true;
  96     break;
  97   default:
  98     break;
  99   }
 100   if (opts::ExpandRelocs) {
 101     DictScope Group(W, "Relocation");
 102     W.printNumber("Type", RelocTypeName, RelocType);
 103     W.printHex("Offset", Reloc.getOffset());
 104     if (!SymName.empty())
 105       W.printString("Symbol", SymName);
 106     else
 107       W.printHex("Index", WasmReloc.Index);
 108     if (HasAddend)
 109       W.printNumber("Addend", WasmReloc.Addend);
 110   } else {
 111     raw_ostream& OS = W.startLine();
 112     OS << W.hex(Reloc.getOffset()) << " " << RelocTypeName << " ";
 113     if (!SymName.empty())
 114       OS << SymName;
 115     else
 116       OS << WasmReloc.Index;
 117     if (HasAddend)
 118       OS << " " << WasmReloc.Addend;
 119     OS << "\n";
 120   }
 121 }
 122
 123 void WasmDumper::printRelocations() {
 124   ListScope D(W, "Relocations");
 125
 126   int SectionNumber = 0;
 127   for (const SectionRef &Section : Obj->sections()) {
 128     bool PrintedGroup = false;
 129     StringRef Name;
 130     error(Section.getName(Name));
 131     ++SectionNumber;
 132
 133     for (const RelocationRef &Reloc : Section.relocations()) {
 134       if (!PrintedGroup) {
 135         W.startLine() << "Section (" << SectionNumber << ") " << Name << " {\n";
 136         W.indent();
 137         PrintedGroup = true;
 138       }
 139
 140       printRelocation(Section, Reloc);
 141     }
 142
 143     if (PrintedGroup) {
 144       W.unindent();
 145       W.startLine() << "}\n";
 146     }
 147   }
 148 }
 149
 150 void WasmDumper::printSymbols() {
 151   ListScope Group(W, "Symbols");
 152
 153   for (const SymbolRef &Symbol : Obj->symbols())
 154     printSymbol(Symbol);
 155 }
 156
 157 void WasmDumper::printSections() {
 158   ListScope Group(W, "Sections");
 159   for (const SectionRef &Section : Obj->sections()) {
 160     const WasmSection &WasmSec = Obj->getWasmSection(Section);
 161     DictScope SectionD(W, "Section");
 162     W.printEnum("Type", WasmSec.Type, makeArrayRef(WasmSectionTypes));
 163     W.printNumber("Size", static_cast<uint64_t>(WasmSec.Content.size()));
 164     W.printNumber("Offset", WasmSec.Offset);
 165     switch (WasmSec.Type) {
 166     case wasm::WASM_SEC_CUSTOM:
 167       W.printString("Name", WasmSec.Name);
 168       if (WasmSec.Name == "linking") {
 169         const wasm::WasmLinkingData &LinkingData = Obj->linkingData();
 170         if (!LinkingData.InitFunctions.empty()) {
 171           ListScope Group(W, "InitFunctions");
 172           for (const wasm::WasmInitFunc &F: LinkingData.InitFunctions)
 173             W.startLine() << F.Symbol << " (priority=" << F.Priority << ")\n";
 174         }
 175       }
 176       break;
 177     case wasm::WASM_SEC_DATA: {
 178       ListScope Group(W, "Segments");
 179       for (const WasmSegment &Segment : Obj->dataSegments()) {
 180         const wasm::WasmDataSegment& Seg = Segment.Data;
 181         DictScope Group(W, "Segment");
 182         if (!Seg.Name.empty())
 183           W.printString("Name", Seg.Name);
 184         W.printNumber("Size", static_cast<uint64_t>(Seg.Content.size()));
 185         if (Seg.Offset.Opcode == wasm::WASM_OPCODE_I32_CONST)
 186           W.printNumber("Offset", Seg.Offset.Value.Int32);
 187       }
 188       break;
 189     }
 190     case wasm::WASM_SEC_MEMORY:
 191       ListScope Group(W, "Memories");
 192       for (const wasm::WasmLimits &Memory : Obj->memories()) {
 193         DictScope Group(W, "Memory");
 194         W.printNumber("InitialPages", Memory.Initial);
 195         if (Memory.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX) {
 196           W.printNumber("MaxPages", WasmSec.Offset);
 197         }
 198       }
 199       break;
 200     }
 201
 202     if (opts::SectionRelocations) {
 203       ListScope D(W, "Relocations");
 204       for (const RelocationRef &Reloc : Section.relocations())
 205         printRelocation(Section, Reloc);
 206     }
 207
 208     if (opts::SectionData) {
 209       W.printBinaryBlock("SectionData", WasmSec.Content);
 210     }
 211   }
 212 }
 213
 214 void WasmDumper::printSymbol(const SymbolRef &Sym) {
 215   DictScope D(W, "Symbol");
 216   WasmSymbol Symbol = Obj->getWasmSymbol(Sym.getRawDataRefImpl());
 217   W.printString("Name", Symbol.Info.Name);
 218   W.printEnum("Type", Symbol.Info.Kind, makeArrayRef(WasmSymbolTypes));
 219   W.printHex("Flags", Symbol.Info.Flags);
 220 }
 221
 222 }
 223
 224 namespace llvm {
 225
 226 std::error_code createWasmDumper(const object::ObjectFile *Obj,
 227                                  ScopedPrinter &Writer,
 228                                  std::unique_ptr<ObjDumper> &Result) {
 229   const WasmObjectFile *WasmObj = dyn_cast<WasmObjectFile>(Obj);
 230   assert(WasmObj && "createWasmDumper called with non-wasm object");
 231
 232   Result.reset(new WasmDumper(WasmObj, Writer));
 233   return readobj_error::success;
 234 }
 235
 236 } // namespace llvm