1 //===------ utils/wasm2yaml.cpp - obj2yaml conversion tool ------*- C++ -*-===//
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 #include "obj2yaml.h"
11 #include "llvm/Object/COFF.h"
12 #include "llvm/ObjectYAML/WasmYAML.h"
13 #include "llvm/Support/ErrorHandling.h"
14 #include "llvm/Support/YAMLTraits.h"
15 
16 using namespace llvm;
17 using object::WasmSection;
18 
19 namespace {
20 
21 class WasmDumper {
22   const object::WasmObjectFile &Obj;
23 
24 public:
25   WasmDumper(const object::WasmObjectFile &O) : Obj(O) {}
26 
27   ErrorOr<WasmYAML::Object *> dump();
28 
29   std::unique_ptr<WasmYAML::CustomSection>
30   dumpCustomSection(const WasmSection &WasmSec);
31 };
32 
33 } // namespace
34 
35 static WasmYAML::Table make_table(const wasm::WasmTable &Table) {
36   WasmYAML::Table T;
37   T.ElemType = Table.ElemType;
38   T.TableLimits.Flags = Table.Limits.Flags;
39   T.TableLimits.Initial = Table.Limits.Initial;
40   T.TableLimits.Maximum = Table.Limits.Maximum;
41   return T;
42 }
43 
44 static WasmYAML::Limits make_limits(const wasm::WasmLimits &Limits) {
45   WasmYAML::Limits L;
46   L.Flags = Limits.Flags;
47   L.Initial = Limits.Initial;
48   L.Maximum = Limits.Maximum;
49   return L;
50 }
51 
52 std::unique_ptr<WasmYAML::CustomSection> WasmDumper::dumpCustomSection(const WasmSection &WasmSec) {
53   std::unique_ptr<WasmYAML::CustomSection> CustomSec;
54   if (WasmSec.Name == "name") {
55     std::unique_ptr<WasmYAML::NameSection> NameSec = make_unique<WasmYAML::NameSection>();
56     for (const llvm::wasm::WasmFunctionName &Func: Obj.debugNames()) {
57       WasmYAML::NameEntry NameEntry;
58       NameEntry.Name = Func.Name;
59       NameEntry.Index = Func.Index;
60       NameSec->FunctionNames.push_back(NameEntry);
61     }
62     CustomSec = std::move(NameSec);
63   } else if (WasmSec.Name == "linking") {
64     std::unique_ptr<WasmYAML::LinkingSection> LinkingSec = make_unique<WasmYAML::LinkingSection>();
65     ArrayRef<StringRef> Comdats = Obj.linkingData().Comdats;
66     for (StringRef ComdatName : Comdats)
67       LinkingSec->Comdats.emplace_back(WasmYAML::Comdat{ComdatName, {}});
68     for (auto &Func : Obj.functions()) {
69       if (Func.Comdat != UINT32_MAX) {
70         LinkingSec->Comdats[Func.Comdat].Entries.emplace_back(
71                 WasmYAML::ComdatEntry{wasm::WASM_COMDAT_FUNCTION, Func.Index});
72       }
73     }
74     uint32_t SegmentIndex = 0;
75     for (const object::WasmSegment &Segment : Obj.dataSegments()) {
76       if (!Segment.Data.Name.empty()) {
77         WasmYAML::SegmentInfo SegmentInfo;
78         SegmentInfo.Name = Segment.Data.Name;
79         SegmentInfo.Index = SegmentIndex;
80         SegmentInfo.Alignment = Segment.Data.Alignment;
81         SegmentInfo.Flags = Segment.Data.Flags;
82         LinkingSec->SegmentInfos.push_back(SegmentInfo);
83       }
84       if (Segment.Data.Comdat != UINT32_MAX) {
85         LinkingSec->Comdats[Segment.Data.Comdat].Entries.emplace_back(
86             WasmYAML::ComdatEntry{wasm::WASM_COMDAT_DATA, SegmentIndex});
87       }
88       SegmentIndex++;
89     }
90     uint32_t SymbolIndex = 0;
91     for (const wasm::WasmSymbolInfo &Symbol : Obj.linkingData().SymbolTable) {
92       WasmYAML::SymbolInfo Info;
93       Info.Index = SymbolIndex++;
94       Info.Kind = static_cast<uint32_t>(Symbol.Kind);
95       Info.Name = Symbol.Name;
96       Info.Flags = Symbol.Flags;
97       switch (Symbol.Kind) {
98       case wasm::WASM_SYMBOL_TYPE_DATA:
99         Info.DataRef = Symbol.DataRef;
100         break;
101       case wasm::WASM_SYMBOL_TYPE_FUNCTION:
102       case wasm::WASM_SYMBOL_TYPE_GLOBAL:
103         Info.ElementIndex = Symbol.ElementIndex;
104         break;
105       }
106       LinkingSec->SymbolTable.emplace_back(Info);
107     }
108     for (const wasm::WasmInitFunc &Func : Obj.linkingData().InitFunctions) {
109       WasmYAML::InitFunction F{Func.Priority, Func.Symbol};
110       LinkingSec->InitFunctions.emplace_back(F);
111     }
112     CustomSec = std::move(LinkingSec);
113   } else {
114     CustomSec = make_unique<WasmYAML::CustomSection>(WasmSec.Name);
115   }
116   CustomSec->Payload = yaml::BinaryRef(WasmSec.Content);
117   return CustomSec;
118 }
119 
120 ErrorOr<WasmYAML::Object *> WasmDumper::dump() {
121   auto Y = make_unique<WasmYAML::Object>();
122 
123   // Dump header
124   Y->Header.Version = Obj.getHeader().Version;
125 
126   // Dump sections
127   for (const auto &Sec : Obj.sections()) {
128     const WasmSection &WasmSec = Obj.getWasmSection(Sec);
129     std::unique_ptr<WasmYAML::Section> S;
130     switch (WasmSec.Type) {
131     case wasm::WASM_SEC_CUSTOM: {
132       if (WasmSec.Name.startswith("reloc.")) {
133         // Relocations are attached the sections they apply to rather than
134         // being represented as a custom section in the YAML output.
135         continue;
136       }
137       S = dumpCustomSection(WasmSec);
138       break;
139     }
140     case wasm::WASM_SEC_TYPE: {
141       auto TypeSec = make_unique<WasmYAML::TypeSection>();
142       uint32_t Index = 0;
143       for (const auto &FunctionSig : Obj.types()) {
144         WasmYAML::Signature Sig;
145         Sig.Index = Index++;
146         Sig.ReturnType = FunctionSig.ReturnType;
147         for (const auto &ParamType : FunctionSig.ParamTypes)
148           Sig.ParamTypes.push_back(ParamType);
149         TypeSec->Signatures.push_back(Sig);
150       }
151       S = std::move(TypeSec);
152       break;
153     }
154     case wasm::WASM_SEC_IMPORT: {
155       auto ImportSec = make_unique<WasmYAML::ImportSection>();
156       for (auto &Import : Obj.imports()) {
157         WasmYAML::Import Im;
158         Im.Module = Import.Module;
159         Im.Field = Import.Field;
160         Im.Kind = Import.Kind;
161         switch (Im.Kind) {
162         case wasm::WASM_EXTERNAL_FUNCTION:
163           Im.SigIndex = Import.SigIndex;
164           break;
165         case wasm::WASM_EXTERNAL_GLOBAL:
166           Im.GlobalImport.Type = Import.Global.Type;
167           Im.GlobalImport.Mutable = Import.Global.Mutable;
168           break;
169         case wasm::WASM_EXTERNAL_TABLE:
170           Im.TableImport = make_table(Import.Table);
171           break;
172         case wasm::WASM_EXTERNAL_MEMORY:
173           Im.Memory = make_limits(Import.Memory);
174           break;
175         }
176         ImportSec->Imports.push_back(Im);
177       }
178       S = std::move(ImportSec);
179       break;
180     }
181     case wasm::WASM_SEC_FUNCTION: {
182       auto FuncSec = make_unique<WasmYAML::FunctionSection>();
183       for (const auto &Func : Obj.functionTypes()) {
184         FuncSec->FunctionTypes.push_back(Func);
185       }
186       S = std::move(FuncSec);
187       break;
188     }
189     case wasm::WASM_SEC_TABLE: {
190       auto TableSec = make_unique<WasmYAML::TableSection>();
191       for (const wasm::WasmTable &Table : Obj.tables()) {
192         TableSec->Tables.push_back(make_table(Table));
193       }
194       S = std::move(TableSec);
195       break;
196     }
197     case wasm::WASM_SEC_MEMORY: {
198       auto MemorySec = make_unique<WasmYAML::MemorySection>();
199       for (const wasm::WasmLimits &Memory : Obj.memories()) {
200         MemorySec->Memories.push_back(make_limits(Memory));
201       }
202       S = std::move(MemorySec);
203       break;
204     }
205     case wasm::WASM_SEC_GLOBAL: {
206       auto GlobalSec = make_unique<WasmYAML::GlobalSection>();
207       for (auto &Global : Obj.globals()) {
208         WasmYAML::Global G;
209         G.Index = Global.Index;
210         G.Type = Global.Type.Type;
211         G.Mutable = Global.Type.Mutable;
212         G.InitExpr = Global.InitExpr;
213         GlobalSec->Globals.push_back(G);
214       }
215       S = std::move(GlobalSec);
216       break;
217     }
218     case wasm::WASM_SEC_START: {
219       auto StartSec = make_unique<WasmYAML::StartSection>();
220       StartSec->StartFunction = Obj.startFunction();
221       S = std::move(StartSec);
222       break;
223     }
224     case wasm::WASM_SEC_EXPORT: {
225       auto ExportSec = make_unique<WasmYAML::ExportSection>();
226       for (auto &Export : Obj.exports()) {
227         WasmYAML::Export Ex;
228         Ex.Name = Export.Name;
229         Ex.Kind = Export.Kind;
230         Ex.Index = Export.Index;
231         ExportSec->Exports.push_back(Ex);
232       }
233       S = std::move(ExportSec);
234       break;
235     }
236     case wasm::WASM_SEC_ELEM: {
237       auto ElemSec = make_unique<WasmYAML::ElemSection>();
238       for (auto &Segment : Obj.elements()) {
239         WasmYAML::ElemSegment Seg;
240         Seg.TableIndex = Segment.TableIndex;
241         Seg.Offset = Segment.Offset;
242         for (auto &Func : Segment.Functions) {
243           Seg.Functions.push_back(Func);
244         }
245         ElemSec->Segments.push_back(Seg);
246       }
247       S = std::move(ElemSec);
248       break;
249     }
250     case wasm::WASM_SEC_CODE: {
251       auto CodeSec = make_unique<WasmYAML::CodeSection>();
252       for (auto &Func : Obj.functions()) {
253         WasmYAML::Function Function;
254         Function.Index = Func.Index;
255         for (auto &Local : Func.Locals) {
256           WasmYAML::LocalDecl LocalDecl;
257           LocalDecl.Type = Local.Type;
258           LocalDecl.Count = Local.Count;
259           Function.Locals.push_back(LocalDecl);
260         }
261         Function.Body = yaml::BinaryRef(Func.Body);
262         CodeSec->Functions.push_back(Function);
263       }
264       S = std::move(CodeSec);
265       break;
266     }
267     case wasm::WASM_SEC_DATA: {
268       auto DataSec = make_unique<WasmYAML::DataSection>();
269       for (const object::WasmSegment &Segment : Obj.dataSegments()) {
270         WasmYAML::DataSegment Seg;
271         Seg.SectionOffset = Segment.SectionOffset;
272         Seg.MemoryIndex = Segment.Data.MemoryIndex;
273         Seg.Offset = Segment.Data.Offset;
274         Seg.Content = yaml::BinaryRef(Segment.Data.Content);
275         DataSec->Segments.push_back(Seg);
276       }
277       S = std::move(DataSec);
278       break;
279     }
280     default:
281       llvm_unreachable("Unknown section type");
282       break;
283     }
284     for (const wasm::WasmRelocation &Reloc: WasmSec.Relocations) {
285       WasmYAML::Relocation R;
286       R.Type = Reloc.Type;
287       R.Index = Reloc.Index;
288       R.Offset = Reloc.Offset;
289       R.Addend = Reloc.Addend;
290       S->Relocations.push_back(R);
291     }
292     Y->Sections.push_back(std::move(S));
293   }
294 
295   return Y.release();
296 }
297 
298 std::error_code wasm2yaml(raw_ostream &Out, const object::WasmObjectFile &Obj) {
299   WasmDumper Dumper(Obj);
300   ErrorOr<WasmYAML::Object *> YAMLOrErr = Dumper.dump();
301   if (std::error_code EC = YAMLOrErr.getError())
302     return EC;
303 
304   std::unique_ptr<WasmYAML::Object> YAML(YAMLOrErr.get());
305   yaml::Output Yout(Out);
306   Yout << *YAML;
307 
308   return std::error_code();
309 }
310