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>
53 WasmDumper::dumpCustomSection(const WasmSection &WasmSec) {
54   std::unique_ptr<WasmYAML::CustomSection> CustomSec;
55   if (WasmSec.Name == "dylink") {
56     std::unique_ptr<WasmYAML::DylinkSection> DylinkSec =
57         make_unique<WasmYAML::DylinkSection>();
58     const wasm::WasmDylinkInfo& Info = Obj.dylinkInfo();
59     DylinkSec->MemorySize = Info.MemorySize;
60     DylinkSec->MemoryAlignment = Info.MemoryAlignment;
61     DylinkSec->TableSize = Info.TableSize;
62     DylinkSec->TableAlignment = Info.TableAlignment;
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.Flags;
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 {
136     CustomSec = make_unique<WasmYAML::CustomSection>(WasmSec.Name);
137   }
138   CustomSec->Payload = yaml::BinaryRef(WasmSec.Content);
139   return CustomSec;
140 }
141 
142 ErrorOr<WasmYAML::Object *> WasmDumper::dump() {
143   auto Y = make_unique<WasmYAML::Object>();
144 
145   // Dump header
146   Y->Header.Version = Obj.getHeader().Version;
147 
148   // Dump sections
149   for (const auto &Sec : Obj.sections()) {
150     const WasmSection &WasmSec = Obj.getWasmSection(Sec);
151     std::unique_ptr<WasmYAML::Section> S;
152     switch (WasmSec.Type) {
153     case wasm::WASM_SEC_CUSTOM: {
154       if (WasmSec.Name.startswith("reloc.")) {
155         // Relocations are attached the sections they apply to rather than
156         // being represented as a custom section in the YAML output.
157         continue;
158       }
159       S = dumpCustomSection(WasmSec);
160       break;
161     }
162     case wasm::WASM_SEC_TYPE: {
163       auto TypeSec = make_unique<WasmYAML::TypeSection>();
164       uint32_t Index = 0;
165       for (const auto &FunctionSig : Obj.types()) {
166         WasmYAML::Signature Sig;
167         Sig.Index = Index++;
168         Sig.ReturnType = wasm::WASM_TYPE_NORESULT;
169         assert(FunctionSig.Returns.size() <= 1 &&
170                "Functions with multiple returns are not supported");
171         if (FunctionSig.Returns.size())
172           Sig.ReturnType = static_cast<uint32_t>(FunctionSig.Returns[0]);
173         for (const auto &ParamType : FunctionSig.Params)
174           Sig.ParamTypes.push_back(static_cast<uint32_t>(ParamType));
175         TypeSec->Signatures.push_back(Sig);
176       }
177       S = std::move(TypeSec);
178       break;
179     }
180     case wasm::WASM_SEC_IMPORT: {
181       auto ImportSec = make_unique<WasmYAML::ImportSection>();
182       for (auto &Import : Obj.imports()) {
183         WasmYAML::Import Im;
184         Im.Module = Import.Module;
185         Im.Field = Import.Field;
186         Im.Kind = Import.Kind;
187         switch (Im.Kind) {
188         case wasm::WASM_EXTERNAL_FUNCTION:
189           Im.SigIndex = Import.SigIndex;
190           break;
191         case wasm::WASM_EXTERNAL_GLOBAL:
192           Im.GlobalImport.Type = Import.Global.Type;
193           Im.GlobalImport.Mutable = Import.Global.Mutable;
194           break;
195         case wasm::WASM_EXTERNAL_EVENT:
196           Im.EventImport.Attribute = Import.Event.Attribute;
197           Im.EventImport.SigIndex = Import.Event.SigIndex;
198           break;
199         case wasm::WASM_EXTERNAL_TABLE:
200           Im.TableImport = make_table(Import.Table);
201           break;
202         case wasm::WASM_EXTERNAL_MEMORY:
203           Im.Memory = make_limits(Import.Memory);
204           break;
205         }
206         ImportSec->Imports.push_back(Im);
207       }
208       S = std::move(ImportSec);
209       break;
210     }
211     case wasm::WASM_SEC_FUNCTION: {
212       auto FuncSec = make_unique<WasmYAML::FunctionSection>();
213       for (const auto &Func : Obj.functionTypes()) {
214         FuncSec->FunctionTypes.push_back(Func);
215       }
216       S = std::move(FuncSec);
217       break;
218     }
219     case wasm::WASM_SEC_TABLE: {
220       auto TableSec = make_unique<WasmYAML::TableSection>();
221       for (const wasm::WasmTable &Table : Obj.tables()) {
222         TableSec->Tables.push_back(make_table(Table));
223       }
224       S = std::move(TableSec);
225       break;
226     }
227     case wasm::WASM_SEC_MEMORY: {
228       auto MemorySec = make_unique<WasmYAML::MemorySection>();
229       for (const wasm::WasmLimits &Memory : Obj.memories()) {
230         MemorySec->Memories.push_back(make_limits(Memory));
231       }
232       S = std::move(MemorySec);
233       break;
234     }
235     case wasm::WASM_SEC_GLOBAL: {
236       auto GlobalSec = make_unique<WasmYAML::GlobalSection>();
237       for (auto &Global : Obj.globals()) {
238         WasmYAML::Global G;
239         G.Index = Global.Index;
240         G.Type = Global.Type.Type;
241         G.Mutable = Global.Type.Mutable;
242         G.InitExpr = Global.InitExpr;
243         GlobalSec->Globals.push_back(G);
244       }
245       S = std::move(GlobalSec);
246       break;
247     }
248     case wasm::WASM_SEC_EVENT: {
249       auto EventSec = make_unique<WasmYAML::EventSection>();
250       for (auto &Event : Obj.events()) {
251         WasmYAML::Event E;
252         E.Index = Event.Index;
253         E.Attribute = Event.Type.Attribute;
254         E.SigIndex = Event.Type.SigIndex;
255         EventSec->Events.push_back(E);
256       }
257       S = std::move(EventSec);
258       break;
259     }
260     case wasm::WASM_SEC_START: {
261       auto StartSec = make_unique<WasmYAML::StartSection>();
262       StartSec->StartFunction = Obj.startFunction();
263       S = std::move(StartSec);
264       break;
265     }
266     case wasm::WASM_SEC_EXPORT: {
267       auto ExportSec = make_unique<WasmYAML::ExportSection>();
268       for (auto &Export : Obj.exports()) {
269         WasmYAML::Export Ex;
270         Ex.Name = Export.Name;
271         Ex.Kind = Export.Kind;
272         Ex.Index = Export.Index;
273         ExportSec->Exports.push_back(Ex);
274       }
275       S = std::move(ExportSec);
276       break;
277     }
278     case wasm::WASM_SEC_ELEM: {
279       auto ElemSec = make_unique<WasmYAML::ElemSection>();
280       for (auto &Segment : Obj.elements()) {
281         WasmYAML::ElemSegment Seg;
282         Seg.TableIndex = Segment.TableIndex;
283         Seg.Offset = Segment.Offset;
284         for (auto &Func : Segment.Functions) {
285           Seg.Functions.push_back(Func);
286         }
287         ElemSec->Segments.push_back(Seg);
288       }
289       S = std::move(ElemSec);
290       break;
291     }
292     case wasm::WASM_SEC_CODE: {
293       auto CodeSec = make_unique<WasmYAML::CodeSection>();
294       for (auto &Func : Obj.functions()) {
295         WasmYAML::Function Function;
296         Function.Index = Func.Index;
297         for (auto &Local : Func.Locals) {
298           WasmYAML::LocalDecl LocalDecl;
299           LocalDecl.Type = Local.Type;
300           LocalDecl.Count = Local.Count;
301           Function.Locals.push_back(LocalDecl);
302         }
303         Function.Body = yaml::BinaryRef(Func.Body);
304         CodeSec->Functions.push_back(Function);
305       }
306       S = std::move(CodeSec);
307       break;
308     }
309     case wasm::WASM_SEC_DATA: {
310       auto DataSec = make_unique<WasmYAML::DataSection>();
311       for (const object::WasmSegment &Segment : Obj.dataSegments()) {
312         WasmYAML::DataSegment Seg;
313         Seg.SectionOffset = Segment.SectionOffset;
314         Seg.MemoryIndex = Segment.Data.MemoryIndex;
315         Seg.Offset = Segment.Data.Offset;
316         Seg.Content = yaml::BinaryRef(Segment.Data.Content);
317         DataSec->Segments.push_back(Seg);
318       }
319       S = std::move(DataSec);
320       break;
321     }
322     default:
323       llvm_unreachable("Unknown section type");
324       break;
325     }
326     for (const wasm::WasmRelocation &Reloc : WasmSec.Relocations) {
327       WasmYAML::Relocation R;
328       R.Type = Reloc.Type;
329       R.Index = Reloc.Index;
330       R.Offset = Reloc.Offset;
331       R.Addend = Reloc.Addend;
332       S->Relocations.push_back(R);
333     }
334     Y->Sections.push_back(std::move(S));
335   }
336 
337   return Y.release();
338 }
339 
340 std::error_code wasm2yaml(raw_ostream &Out, const object::WasmObjectFile &Obj) {
341   WasmDumper Dumper(Obj);
342   ErrorOr<WasmYAML::Object *> YAMLOrErr = Dumper.dump();
343   if (std::error_code EC = YAMLOrErr.getError())
344     return EC;
345 
346   std::unique_ptr<WasmYAML::Object> YAML(YAMLOrErr.get());
347   yaml::Output Yout(Out);
348   Yout << *YAML;
349 
350   return std::error_code();
351 }
352