xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-readobj/WasmDumper.cpp (revision 6be3386466ab79a84b48429ae66244f21526d3df)
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 
19 using namespace llvm;
20 using namespace object;
21 
22 namespace {
23 
24 static 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 
32 static 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 
43 static 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 
58 class WasmDumper : public ObjDumper {
59 public:
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 
69 protected:
70   void printSymbol(const SymbolRef &Sym);
71   void printRelocation(const SectionRef &Section, const RelocationRef &Reloc);
72 
73 private:
74   void printSymbols() override;
75   void printDynamicSymbols() override { llvm_unreachable("unimplemented"); }
76 
77   const WasmObjectFile *Obj;
78 };
79 
80 void WasmDumper::printFileHeaders() {
81   W.printHex("Version", Obj->getHeader().Version);
82 }
83 
84 void 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 
121 void 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 
148 void WasmDumper::printSymbols() {
149   ListScope Group(W, "Symbols");
150 
151   for (const SymbolRef &Symbol : Obj->symbols())
152     printSymbol(Symbol);
153 }
154 
155 void 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 
216 void 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 
242 namespace llvm {
243 
244 std::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