1 //===------ utils/wasm2yaml.cpp - obj2yaml conversion tool ------*- C++ -*-===//
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 #include "obj2yaml.h"
10 #include "llvm/Object/COFF.h"
11 #include "llvm/ObjectYAML/WasmYAML.h"
12 #include "llvm/Support/ErrorHandling.h"
13 #include "llvm/Support/YAMLTraits.h"
14 
15 using namespace llvm;
16 using object::WasmSection;
17 
18 namespace {
19 
20 class WasmDumper {
21   const object::WasmObjectFile &Obj;
22 
23 public:
24   WasmDumper(const object::WasmObjectFile &O) : Obj(O) {}
25 
26   ErrorOr<WasmYAML::Object *> dump();
27 
28   std::unique_ptr<WasmYAML::CustomSection>
29   dumpCustomSection(const WasmSection &WasmSec);
30 };
31 
32 } // namespace
33 
34 static WasmYAML::Table makeTable(const wasm::WasmTable &Table) {
35   WasmYAML::Table T;
36   T.ElemType = Table.ElemType;
37   T.TableLimits.Flags = Table.Limits.Flags;
38   T.TableLimits.Initial = Table.Limits.Initial;
39   T.TableLimits.Maximum = Table.Limits.Maximum;
40   return T;
41 }
42 
43 static WasmYAML::Limits makeLimits(const wasm::WasmLimits &Limits) {
44   WasmYAML::Limits L;
45   L.Flags = Limits.Flags;
46   L.Initial = Limits.Initial;
47   L.Maximum = Limits.Maximum;
48   return L;
49 }
50 
51 std::unique_ptr<WasmYAML::CustomSection>
52 WasmDumper::dumpCustomSection(const WasmSection &WasmSec) {
53   std::unique_ptr<WasmYAML::CustomSection> CustomSec;
54   if (WasmSec.Name == "dylink") {
55     std::unique_ptr<WasmYAML::DylinkSection> DylinkSec =
56         make_unique<WasmYAML::DylinkSection>();
57     const wasm::WasmDylinkInfo& Info = Obj.dylinkInfo();
58     DylinkSec->MemorySize = Info.MemorySize;
59     DylinkSec->MemoryAlignment = Info.MemoryAlignment;
60     DylinkSec->TableSize = Info.TableSize;
61     DylinkSec->TableAlignment = Info.TableAlignment;
62     DylinkSec->Needed = Info.Needed;
63     CustomSec = std::move(DylinkSec);
64   } else if (WasmSec.Name == "name") {
65     std::unique_ptr<WasmYAML::NameSection> NameSec =
66         make_unique<WasmYAML::NameSection>();
67     for (const llvm::wasm::WasmFunctionName &Func : Obj.debugNames()) {
68       WasmYAML::NameEntry NameEntry;
69       NameEntry.Name = Func.Name;
70       NameEntry.Index = Func.Index;
71       NameSec->FunctionNames.push_back(NameEntry);
72     }
73     CustomSec = std::move(NameSec);
74   } else if (WasmSec.Name == "linking") {
75     std::unique_ptr<WasmYAML::LinkingSection> LinkingSec =
76         make_unique<WasmYAML::LinkingSection>();
77     LinkingSec->Version = Obj.linkingData().Version;
78 
79     ArrayRef<StringRef> Comdats = Obj.linkingData().Comdats;
80     for (StringRef ComdatName : Comdats)
81       LinkingSec->Comdats.emplace_back(WasmYAML::Comdat{ComdatName, {}});
82     for (auto &Func : Obj.functions()) {
83       if (Func.Comdat != UINT32_MAX) {
84         LinkingSec->Comdats[Func.Comdat].Entries.emplace_back(
85             WasmYAML::ComdatEntry{wasm::WASM_COMDAT_FUNCTION, Func.Index});
86       }
87     }
88 
89     uint32_t SegmentIndex = 0;
90     for (const object::WasmSegment &Segment : Obj.dataSegments()) {
91       if (!Segment.Data.Name.empty()) {
92         WasmYAML::SegmentInfo SegmentInfo;
93         SegmentInfo.Name = Segment.Data.Name;
94         SegmentInfo.Index = SegmentIndex;
95         SegmentInfo.Alignment = Segment.Data.Alignment;
96         SegmentInfo.Flags = Segment.Data.LinkerFlags;
97         LinkingSec->SegmentInfos.push_back(SegmentInfo);
98       }
99       if (Segment.Data.Comdat != UINT32_MAX) {
100         LinkingSec->Comdats[Segment.Data.Comdat].Entries.emplace_back(
101             WasmYAML::ComdatEntry{wasm::WASM_COMDAT_DATA, SegmentIndex});
102       }
103       SegmentIndex++;
104     }
105 
106     uint32_t SymbolIndex = 0;
107     for (const wasm::WasmSymbolInfo &Symbol : Obj.linkingData().SymbolTable) {
108       WasmYAML::SymbolInfo Info;
109       Info.Index = SymbolIndex++;
110       Info.Kind = static_cast<uint32_t>(Symbol.Kind);
111       Info.Name = Symbol.Name;
112       Info.Flags = Symbol.Flags;
113       switch (Symbol.Kind) {
114       case wasm::WASM_SYMBOL_TYPE_DATA:
115         Info.DataRef = Symbol.DataRef;
116         break;
117       case wasm::WASM_SYMBOL_TYPE_FUNCTION:
118       case wasm::WASM_SYMBOL_TYPE_GLOBAL:
119       case wasm::WASM_SYMBOL_TYPE_EVENT:
120         Info.ElementIndex = Symbol.ElementIndex;
121         break;
122       case wasm::WASM_SYMBOL_TYPE_SECTION:
123         Info.ElementIndex = Symbol.ElementIndex;
124         break;
125       }
126       LinkingSec->SymbolTable.emplace_back(Info);
127     }
128 
129     for (const wasm::WasmInitFunc &Func : Obj.linkingData().InitFunctions) {
130       WasmYAML::InitFunction F{Func.Priority, Func.Symbol};
131       LinkingSec->InitFunctions.emplace_back(F);
132     }
133 
134     CustomSec = std::move(LinkingSec);
135   } else if (WasmSec.Name == "producers") {
136     std::unique_ptr<WasmYAML::ProducersSection> ProducersSec =
137         make_unique<WasmYAML::ProducersSection>();
138     const llvm::wasm::WasmProducerInfo &Info = Obj.getProducerInfo();
139     for (auto &E : Info.Languages) {
140       WasmYAML::ProducerEntry Producer;
141       Producer.Name = E.first;
142       Producer.Version = E.second;
143       ProducersSec->Languages.push_back(Producer);
144     }
145     for (auto &E : Info.Tools) {
146       WasmYAML::ProducerEntry Producer;
147       Producer.Name = E.first;
148       Producer.Version = E.second;
149       ProducersSec->Tools.push_back(Producer);
150     }
151     for (auto &E : Info.SDKs) {
152       WasmYAML::ProducerEntry Producer;
153       Producer.Name = E.first;
154       Producer.Version = E.second;
155       ProducersSec->SDKs.push_back(Producer);
156     }
157     CustomSec = std::move(ProducersSec);
158   } else {
159     CustomSec = make_unique<WasmYAML::CustomSection>(WasmSec.Name);
160   }
161   CustomSec->Payload = yaml::BinaryRef(WasmSec.Content);
162   return CustomSec;
163 }
164 
165 ErrorOr<WasmYAML::Object *> WasmDumper::dump() {
166   auto Y = make_unique<WasmYAML::Object>();
167 
168   // Dump header
169   Y->Header.Version = Obj.getHeader().Version;
170 
171   // Dump sections
172   for (const auto &Sec : Obj.sections()) {
173     const WasmSection &WasmSec = Obj.getWasmSection(Sec);
174     std::unique_ptr<WasmYAML::Section> S;
175     switch (WasmSec.Type) {
176     case wasm::WASM_SEC_CUSTOM: {
177       if (WasmSec.Name.startswith("reloc.")) {
178         // Relocations are attached the sections they apply to rather than
179         // being represented as a custom section in the YAML output.
180         continue;
181       }
182       S = dumpCustomSection(WasmSec);
183       break;
184     }
185     case wasm::WASM_SEC_TYPE: {
186       auto TypeSec = make_unique<WasmYAML::TypeSection>();
187       uint32_t Index = 0;
188       for (const auto &FunctionSig : Obj.types()) {
189         WasmYAML::Signature Sig;
190         Sig.Index = Index++;
191         Sig.ReturnType = wasm::WASM_TYPE_NORESULT;
192         assert(FunctionSig.Returns.size() <= 1 &&
193                "Functions with multiple returns are not supported");
194         if (FunctionSig.Returns.size())
195           Sig.ReturnType = static_cast<uint32_t>(FunctionSig.Returns[0]);
196         for (const auto &ParamType : FunctionSig.Params)
197           Sig.ParamTypes.emplace_back(static_cast<uint32_t>(ParamType));
198         TypeSec->Signatures.push_back(Sig);
199       }
200       S = std::move(TypeSec);
201       break;
202     }
203     case wasm::WASM_SEC_IMPORT: {
204       auto ImportSec = make_unique<WasmYAML::ImportSection>();
205       for (auto &Import : Obj.imports()) {
206         WasmYAML::Import Im;
207         Im.Module = Import.Module;
208         Im.Field = Import.Field;
209         Im.Kind = Import.Kind;
210         switch (Im.Kind) {
211         case wasm::WASM_EXTERNAL_FUNCTION:
212           Im.SigIndex = Import.SigIndex;
213           break;
214         case wasm::WASM_EXTERNAL_GLOBAL:
215           Im.GlobalImport.Type = Import.Global.Type;
216           Im.GlobalImport.Mutable = Import.Global.Mutable;
217           break;
218         case wasm::WASM_EXTERNAL_EVENT:
219           Im.EventImport.Attribute = Import.Event.Attribute;
220           Im.EventImport.SigIndex = Import.Event.SigIndex;
221           break;
222         case wasm::WASM_EXTERNAL_TABLE:
223           Im.TableImport = makeTable(Import.Table);
224           break;
225         case wasm::WASM_EXTERNAL_MEMORY:
226           Im.Memory = makeLimits(Import.Memory);
227           break;
228         }
229         ImportSec->Imports.push_back(Im);
230       }
231       S = std::move(ImportSec);
232       break;
233     }
234     case wasm::WASM_SEC_FUNCTION: {
235       auto FuncSec = make_unique<WasmYAML::FunctionSection>();
236       for (const auto &Func : Obj.functionTypes()) {
237         FuncSec->FunctionTypes.push_back(Func);
238       }
239       S = std::move(FuncSec);
240       break;
241     }
242     case wasm::WASM_SEC_TABLE: {
243       auto TableSec = make_unique<WasmYAML::TableSection>();
244       for (const wasm::WasmTable &Table : Obj.tables()) {
245         TableSec->Tables.push_back(makeTable(Table));
246       }
247       S = std::move(TableSec);
248       break;
249     }
250     case wasm::WASM_SEC_MEMORY: {
251       auto MemorySec = make_unique<WasmYAML::MemorySection>();
252       for (const wasm::WasmLimits &Memory : Obj.memories()) {
253         MemorySec->Memories.push_back(makeLimits(Memory));
254       }
255       S = std::move(MemorySec);
256       break;
257     }
258     case wasm::WASM_SEC_GLOBAL: {
259       auto GlobalSec = make_unique<WasmYAML::GlobalSection>();
260       for (auto &Global : Obj.globals()) {
261         WasmYAML::Global G;
262         G.Index = Global.Index;
263         G.Type = Global.Type.Type;
264         G.Mutable = Global.Type.Mutable;
265         G.InitExpr = Global.InitExpr;
266         GlobalSec->Globals.push_back(G);
267       }
268       S = std::move(GlobalSec);
269       break;
270     }
271     case wasm::WASM_SEC_EVENT: {
272       auto EventSec = make_unique<WasmYAML::EventSection>();
273       for (auto &Event : Obj.events()) {
274         WasmYAML::Event E;
275         E.Index = Event.Index;
276         E.Attribute = Event.Type.Attribute;
277         E.SigIndex = Event.Type.SigIndex;
278         EventSec->Events.push_back(E);
279       }
280       S = std::move(EventSec);
281       break;
282     }
283     case wasm::WASM_SEC_START: {
284       auto StartSec = make_unique<WasmYAML::StartSection>();
285       StartSec->StartFunction = Obj.startFunction();
286       S = std::move(StartSec);
287       break;
288     }
289     case wasm::WASM_SEC_EXPORT: {
290       auto ExportSec = make_unique<WasmYAML::ExportSection>();
291       for (auto &Export : Obj.exports()) {
292         WasmYAML::Export Ex;
293         Ex.Name = Export.Name;
294         Ex.Kind = Export.Kind;
295         Ex.Index = Export.Index;
296         ExportSec->Exports.push_back(Ex);
297       }
298       S = std::move(ExportSec);
299       break;
300     }
301     case wasm::WASM_SEC_ELEM: {
302       auto ElemSec = make_unique<WasmYAML::ElemSection>();
303       for (auto &Segment : Obj.elements()) {
304         WasmYAML::ElemSegment Seg;
305         Seg.TableIndex = Segment.TableIndex;
306         Seg.Offset = Segment.Offset;
307         for (auto &Func : Segment.Functions) {
308           Seg.Functions.push_back(Func);
309         }
310         ElemSec->Segments.push_back(Seg);
311       }
312       S = std::move(ElemSec);
313       break;
314     }
315     case wasm::WASM_SEC_CODE: {
316       auto CodeSec = make_unique<WasmYAML::CodeSection>();
317       for (auto &Func : Obj.functions()) {
318         WasmYAML::Function Function;
319         Function.Index = Func.Index;
320         for (auto &Local : Func.Locals) {
321           WasmYAML::LocalDecl LocalDecl;
322           LocalDecl.Type = Local.Type;
323           LocalDecl.Count = Local.Count;
324           Function.Locals.push_back(LocalDecl);
325         }
326         Function.Body = yaml::BinaryRef(Func.Body);
327         CodeSec->Functions.push_back(Function);
328       }
329       S = std::move(CodeSec);
330       break;
331     }
332     case wasm::WASM_SEC_DATA: {
333       auto DataSec = make_unique<WasmYAML::DataSection>();
334       for (const object::WasmSegment &Segment : Obj.dataSegments()) {
335         WasmYAML::DataSegment Seg;
336         Seg.SectionOffset = Segment.SectionOffset;
337         Seg.InitFlags = Segment.Data.InitFlags;
338         Seg.MemoryIndex = Segment.Data.MemoryIndex;
339         Seg.Offset = Segment.Data.Offset;
340         Seg.Content = yaml::BinaryRef(Segment.Data.Content);
341         DataSec->Segments.push_back(Seg);
342       }
343       S = std::move(DataSec);
344       break;
345     }
346     default:
347       llvm_unreachable("Unknown section type");
348       break;
349     }
350     for (const wasm::WasmRelocation &Reloc : WasmSec.Relocations) {
351       WasmYAML::Relocation R;
352       R.Type = Reloc.Type;
353       R.Index = Reloc.Index;
354       R.Offset = Reloc.Offset;
355       R.Addend = Reloc.Addend;
356       S->Relocations.push_back(R);
357     }
358     Y->Sections.push_back(std::move(S));
359   }
360 
361   return Y.release();
362 }
363 
364 std::error_code wasm2yaml(raw_ostream &Out, const object::WasmObjectFile &Obj) {
365   WasmDumper Dumper(Obj);
366   ErrorOr<WasmYAML::Object *> YAMLOrErr = Dumper.dump();
367   if (std::error_code EC = YAMLOrErr.getError())
368     return EC;
369 
370   std::unique_ptr<WasmYAML::Object> YAML(YAMLOrErr.get());
371   yaml::Output Yout(Out);
372   Yout << *YAML;
373 
374   return std::error_code();
375 }
376