LLVM  8.0.0svn
Wasm.h
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1 //===- WasmObjectFile.h - Wasm object file implementation -------*- 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 // This file declares the WasmObjectFile class, which implements the ObjectFile
11 // interface for Wasm files.
12 //
13 // See: https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #ifndef LLVM_OBJECT_WASM_H
18 #define LLVM_OBJECT_WASM_H
19 
20 #include "llvm/ADT/ArrayRef.h"
21 #include "llvm/ADT/StringMap.h"
22 #include "llvm/ADT/StringRef.h"
23 #include "llvm/BinaryFormat/Wasm.h"
24 #include "llvm/Config/llvm-config.h"
25 #include "llvm/MC/MCSymbolWasm.h"
26 #include "llvm/Object/Binary.h"
27 #include "llvm/Object/ObjectFile.h"
28 #include "llvm/Support/Error.h"
30 #include <cstddef>
31 #include <cstdint>
32 #include <vector>
33 
34 namespace llvm {
35 namespace object {
36 
37 class WasmSymbol {
38 public:
43  : Info(Info), GlobalType(GlobalType), EventType(EventType),
44  Signature(Signature) {}
45 
50 
51  bool isTypeFunction() const {
53  }
54 
55  bool isTypeData() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_DATA; }
56 
57  bool isTypeGlobal() const {
58  return Info.Kind == wasm::WASM_SYMBOL_TYPE_GLOBAL;
59  }
60 
61  bool isTypeSection() const {
62  return Info.Kind == wasm::WASM_SYMBOL_TYPE_SECTION;
63  }
64 
65  bool isTypeEvent() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_EVENT; }
66 
67  bool isDefined() const { return !isUndefined(); }
68 
69  bool isUndefined() const {
70  return (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) != 0;
71  }
72 
73  bool isBindingWeak() const {
75  }
76 
77  bool isBindingGlobal() const {
79  }
80 
81  bool isBindingLocal() const {
83  }
84 
85  unsigned getBinding() const {
87  }
88 
89  bool isHidden() const {
91  }
92 
93  unsigned getVisibility() const {
95  }
96 
97  void print(raw_ostream &Out) const;
98 
99 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
100  LLVM_DUMP_METHOD void dump() const;
101 #endif
102 };
103 
104 struct WasmSection {
105  WasmSection() = default;
106 
107  uint32_t Type = 0; // Section type (See below)
108  uint32_t Offset = 0; // Offset with in the file
109  StringRef Name; // Section name (User-defined sections only)
110  ArrayRef<uint8_t> Content; // Section content
111  std::vector<wasm::WasmRelocation> Relocations; // Relocations for this section
112 };
113 
114 struct WasmSegment {
117 };
118 
119 class WasmObjectFile : public ObjectFile {
120 
121 public:
122  WasmObjectFile(MemoryBufferRef Object, Error &Err);
123 
124  const wasm::WasmObjectHeader &getHeader() const;
125  const WasmSymbol &getWasmSymbol(const DataRefImpl &Symb) const;
126  const WasmSymbol &getWasmSymbol(const SymbolRef &Symbol) const;
127  const WasmSection &getWasmSection(const SectionRef &Section) const;
128  const wasm::WasmRelocation &getWasmRelocation(const RelocationRef &Ref) const;
129 
130  static bool classof(const Binary *v) { return v->isWasm(); }
131 
132  const wasm::WasmDylinkInfo &dylinkInfo() const { return DylinkInfo; }
133  ArrayRef<wasm::WasmSignature> types() const { return Signatures; }
134  ArrayRef<uint32_t> functionTypes() const { return FunctionTypes; }
135  ArrayRef<wasm::WasmImport> imports() const { return Imports; }
136  ArrayRef<wasm::WasmTable> tables() const { return Tables; }
137  ArrayRef<wasm::WasmLimits> memories() const { return Memories; }
138  ArrayRef<wasm::WasmGlobal> globals() const { return Globals; }
139  ArrayRef<wasm::WasmEvent> events() const { return Events; }
140  ArrayRef<wasm::WasmExport> exports() const { return Exports; }
141  ArrayRef<WasmSymbol> syms() const { return Symbols; }
142  const wasm::WasmLinkingData &linkingData() const { return LinkingData; }
143  uint32_t getNumberOfSymbols() const { return Symbols.size(); }
144  ArrayRef<wasm::WasmElemSegment> elements() const { return ElemSegments; }
145  ArrayRef<WasmSegment> dataSegments() const { return DataSegments; }
146  ArrayRef<wasm::WasmFunction> functions() const { return Functions; }
147  ArrayRef<wasm::WasmFunctionName> debugNames() const { return DebugNames; }
148  uint32_t startFunction() const { return StartFunction; }
149  uint32_t getNumImportedGlobals() const { return NumImportedGlobals; }
150  uint32_t getNumImportedFunctions() const { return NumImportedFunctions; }
151  uint32_t getNumImportedEvents() const { return NumImportedEvents; }
152 
153  void moveSymbolNext(DataRefImpl &Symb) const override;
154 
155  uint32_t getSymbolFlags(DataRefImpl Symb) const override;
156 
157  basic_symbol_iterator symbol_begin() const override;
158 
159  basic_symbol_iterator symbol_end() const override;
160  Expected<StringRef> getSymbolName(DataRefImpl Symb) const override;
161 
162  Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const override;
163  uint64_t getWasmSymbolValue(const WasmSymbol &Sym) const;
164  uint64_t getSymbolValueImpl(DataRefImpl Symb) const override;
165  uint32_t getSymbolAlignment(DataRefImpl Symb) const override;
166  uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override;
168  Expected<section_iterator> getSymbolSection(DataRefImpl Symb) const override;
169 
170  // Overrides from SectionRef.
171  void moveSectionNext(DataRefImpl &Sec) const override;
172  std::error_code getSectionName(DataRefImpl Sec,
173  StringRef &Res) const override;
174  uint64_t getSectionAddress(DataRefImpl Sec) const override;
175  uint64_t getSectionIndex(DataRefImpl Sec) const override;
176  uint64_t getSectionSize(DataRefImpl Sec) const override;
177  std::error_code getSectionContents(DataRefImpl Sec,
178  StringRef &Res) const override;
179  uint64_t getSectionAlignment(DataRefImpl Sec) const override;
180  bool isSectionCompressed(DataRefImpl Sec) const override;
181  bool isSectionText(DataRefImpl Sec) const override;
182  bool isSectionData(DataRefImpl Sec) const override;
183  bool isSectionBSS(DataRefImpl Sec) const override;
184  bool isSectionVirtual(DataRefImpl Sec) const override;
185  bool isSectionBitcode(DataRefImpl Sec) const override;
186  relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
187  relocation_iterator section_rel_end(DataRefImpl Sec) const override;
188 
189  // Overrides from RelocationRef.
190  void moveRelocationNext(DataRefImpl &Rel) const override;
191  uint64_t getRelocationOffset(DataRefImpl Rel) const override;
192  symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override;
193  uint64_t getRelocationType(DataRefImpl Rel) const override;
194  void getRelocationTypeName(DataRefImpl Rel,
195  SmallVectorImpl<char> &Result) const override;
196 
197  section_iterator section_begin() const override;
198  section_iterator section_end() const override;
199  uint8_t getBytesInAddress() const override;
200  StringRef getFileFormatName() const override;
201  Triple::ArchType getArch() const override;
202  SubtargetFeatures getFeatures() const override;
203  bool isRelocatableObject() const override;
204  bool isSharedObject() const;
205 
206  struct ReadContext {
207  const uint8_t *Start;
208  const uint8_t *Ptr;
209  const uint8_t *End;
210  };
211 
212 private:
213  bool isValidFunctionIndex(uint32_t Index) const;
214  bool isDefinedFunctionIndex(uint32_t Index) const;
215  bool isValidGlobalIndex(uint32_t Index) const;
216  bool isDefinedGlobalIndex(uint32_t Index) const;
217  bool isValidEventIndex(uint32_t Index) const;
218  bool isDefinedEventIndex(uint32_t Index) const;
219  bool isValidFunctionSymbol(uint32_t Index) const;
220  bool isValidGlobalSymbol(uint32_t Index) const;
221  bool isValidEventSymbol(uint32_t Index) const;
222  bool isValidDataSymbol(uint32_t Index) const;
223  bool isValidSectionSymbol(uint32_t Index) const;
224  wasm::WasmFunction &getDefinedFunction(uint32_t Index);
225  wasm::WasmGlobal &getDefinedGlobal(uint32_t Index);
226  wasm::WasmEvent &getDefinedEvent(uint32_t Index);
227 
228  const WasmSection &getWasmSection(DataRefImpl Ref) const;
229  const wasm::WasmRelocation &getWasmRelocation(DataRefImpl Ref) const;
230 
231  const uint8_t *getPtr(size_t Offset) const;
232  Error parseSection(WasmSection &Sec);
233  Error parseCustomSection(WasmSection &Sec, ReadContext &Ctx);
234 
235  // Standard section types
236  Error parseTypeSection(ReadContext &Ctx);
237  Error parseImportSection(ReadContext &Ctx);
238  Error parseFunctionSection(ReadContext &Ctx);
239  Error parseTableSection(ReadContext &Ctx);
240  Error parseMemorySection(ReadContext &Ctx);
241  Error parseGlobalSection(ReadContext &Ctx);
242  Error parseEventSection(ReadContext &Ctx);
243  Error parseExportSection(ReadContext &Ctx);
244  Error parseStartSection(ReadContext &Ctx);
245  Error parseElemSection(ReadContext &Ctx);
246  Error parseCodeSection(ReadContext &Ctx);
247  Error parseDataSection(ReadContext &Ctx);
248 
249  // Custom section types
250  Error parseDylinkSection(ReadContext &Ctx);
251  Error parseNameSection(ReadContext &Ctx);
252  Error parseLinkingSection(ReadContext &Ctx);
253  Error parseLinkingSectionSymtab(ReadContext &Ctx);
254  Error parseLinkingSectionComdat(ReadContext &Ctx);
255  Error parseRelocSection(StringRef Name, ReadContext &Ctx);
256 
257  wasm::WasmObjectHeader Header;
258  std::vector<WasmSection> Sections;
259  wasm::WasmDylinkInfo DylinkInfo;
260  std::vector<wasm::WasmSignature> Signatures;
261  std::vector<uint32_t> FunctionTypes;
262  std::vector<wasm::WasmTable> Tables;
263  std::vector<wasm::WasmLimits> Memories;
264  std::vector<wasm::WasmGlobal> Globals;
265  std::vector<wasm::WasmEvent> Events;
266  std::vector<wasm::WasmImport> Imports;
267  std::vector<wasm::WasmExport> Exports;
268  std::vector<wasm::WasmElemSegment> ElemSegments;
269  std::vector<WasmSegment> DataSegments;
270  std::vector<wasm::WasmFunction> Functions;
271  std::vector<WasmSymbol> Symbols;
272  std::vector<wasm::WasmFunctionName> DebugNames;
273  uint32_t StartFunction = -1;
274  bool HasLinkingSection = false;
275  bool HasDylinkSection = false;
276  wasm::WasmLinkingData LinkingData;
277  uint32_t NumImportedGlobals = 0;
278  uint32_t NumImportedFunctions = 0;
279  uint32_t NumImportedEvents = 0;
280  uint32_t CodeSection = 0;
281  uint32_t DataSection = 0;
282  uint32_t GlobalSection = 0;
283  uint32_t EventSection = 0;
284 };
285 
287 public:
288  // We define orders for all core wasm sections and known custom sections.
289  enum : int {
290  // Core sections
291  // The order of standard sections is precisely given by the spec.
292  WASM_SEC_ORDER_TYPE = 1,
293  WASM_SEC_ORDER_IMPORT = 2,
294  WASM_SEC_ORDER_FUNCTION = 3,
295  WASM_SEC_ORDER_TABLE = 4,
296  WASM_SEC_ORDER_MEMORY = 5,
297  WASM_SEC_ORDER_GLOBAL = 6,
298  WASM_SEC_ORDER_EVENT = 7,
299  WASM_SEC_ORDER_EXPORT = 8,
300  WASM_SEC_ORDER_START = 9,
301  WASM_SEC_ORDER_ELEM = 10,
302  WASM_SEC_ORDER_DATACOUNT = 11,
303  WASM_SEC_ORDER_CODE = 12,
304  WASM_SEC_ORDER_DATA = 13,
305 
306  // Custom sections
307  // "dylink" should be the very first section in the module
308  WASM_SEC_ORDER_DYLINK = 0,
309  // "linking" section requires DATA section in order to validate data symbols
310  WASM_SEC_ORDER_LINKING = 100,
311  // Must come after "linking" section in order to validate reloc indexes.
312  WASM_SEC_ORDER_RELOC = 101,
313  // "name" section must appear after DATA. Comes after "linking" to allow
314  // symbol table to set default function name.
315  WASM_SEC_ORDER_NAME = 102,
316  // "producers" section must appear after "name" section.
317  WASM_SEC_ORDER_PRODUCERS = 103
318  };
319 
320  bool isValidSectionOrder(unsigned ID, StringRef CustomSectionName = "");
321 
322 private:
323  int LastOrder = -1; // Lastly seen known section's order
324 
325  // Returns -1 for unknown sections.
326  int getSectionOrder(unsigned ID, StringRef CustomSectionName = "");
327 };
328 
329 } // end namespace object
330 
332  Sym.print(OS);
333  return OS;
334 }
335 
336 } // end namespace llvm
337 
338 #endif // LLVM_OBJECT_WASM_H
const wasm::WasmLinkingData & linkingData() const
Definition: Wasm.h:142
bool isTypeData() const
Definition: Wasm.h:55
const wasm::WasmDylinkInfo & dylinkInfo() const
Definition: Wasm.h:132
bool isTypeSection() const
Definition: Wasm.h:61
ArrayRef< WasmSegment > dataSegments() const
Definition: Wasm.h:145
This class represents lattice values for constants.
Definition: AllocatorList.h:24
ArrayRef< wasm::WasmExport > exports() const
Definition: Wasm.h:140
const unsigned WASM_SYMBOL_BINDING_LOCAL
Definition: Wasm.h:283
uint32_t getNumberOfSymbols() const
Definition: Wasm.h:143
bool isTypeGlobal() const
Definition: Wasm.h:57
static const char * getPtr(const MachOObjectFile &O, size_t Offset)
ArrayRef< wasm::WasmImport > imports() const
Definition: Wasm.h:135
uint32_t SectionOffset
Definition: Wasm.h:115
This class is the base class for all object file types.
Definition: ObjectFile.h:202
ArrayRef< uint32_t > functionTypes() const
Definition: Wasm.h:134
ArrayRef< wasm::WasmFunctionName > debugNames() const
Definition: Wasm.h:147
uint32_t getNumImportedGlobals() const
Definition: Wasm.h:149
uint32_t getNumImportedFunctions() const
Definition: Wasm.h:150
bool isBindingGlobal() const
Definition: Wasm.h:77
unsigned getBinding() const
Definition: Wasm.h:85
const unsigned WASM_SYMBOL_UNDEFINED
Definition: Wasm.h:286
std::vector< wasm::WasmRelocation > Relocations
Definition: Wasm.h:111
amdgpu Simplify well known AMD library false Value Value const Twine & Name
static StringRef getSymbolName(SymbolKind SymKind)
ArrayRef< wasm::WasmFunction > functions() const
Definition: Wasm.h:146
This is a value type class that represents a single relocation in the list of relocations in the obje...
Definition: ObjectFile.h:52
The access may reference the value stored in memory.
ArrayRef< wasm::WasmLimits > memories() const
Definition: Wasm.h:137
Tagged union holding either a T or a Error.
Definition: CachePruning.h:23
#define LLVM_DUMP_METHOD
Definition: Compiler.h:74
ArrayRef< wasm::WasmTable > tables() const
Definition: Wasm.h:136
static bool classof(const Binary *v)
Definition: Wasm.h:130
unsigned getVisibility() const
Definition: Wasm.h:93
wasm::WasmDataSegment Data
Definition: Wasm.h:116
ArrayRef< wasm::WasmSignature > types() const
Definition: Wasm.h:133
uint32_t getNumImportedEvents() const
Definition: Wasm.h:151
bool isBindingLocal() const
Definition: Wasm.h:81
LLVM_DUMP_METHOD void dump() const
ArrayRef< uint8_t > Content
Definition: Wasm.h:110
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
const unsigned WASM_SYMBOL_VISIBILITY_HIDDEN
Definition: Wasm.h:285
const wasm::WasmEventType * EventType
Definition: Wasm.h:48
ArrayRef< wasm::WasmElemSegment > elements() const
Definition: Wasm.h:144
const unsigned WASM_SYMBOL_BINDING_WEAK
Definition: Wasm.h:282
ArrayRef< wasm::WasmGlobal > globals() const
Definition: Wasm.h:138
const unsigned WASM_SYMBOL_VISIBILITY_MASK
Definition: Wasm.h:279
bool isDefined() const
Definition: Wasm.h:67
uint32_t startFunction() const
Definition: Wasm.h:148
const unsigned WASM_SYMBOL_BINDING_GLOBAL
Definition: Wasm.h:281
const wasm::WasmSymbolInfo & Info
Definition: Wasm.h:46
ArrayRef< WasmSymbol > syms() const
Definition: Wasm.h:141
bool isTypeFunction() const
Definition: Wasm.h:51
Manages the enabling and disabling of subtarget specific features.
This is a value type class that represents a single symbol in the list of symbols in the object file...
Definition: ObjectFile.h:141
static std::unique_ptr< PDBSymbol > getSymbolType(const PDBSymbol &Symbol)
Definition: UDTLayout.cpp:34
bool isTypeEvent() const
Definition: Wasm.h:65
WasmSymbol(const wasm::WasmSymbolInfo &Info, const wasm::WasmGlobalType *GlobalType, const wasm::WasmEventType *EventType, const wasm::WasmSignature *Signature)
Definition: Wasm.h:39
const unsigned WASM_SYMBOL_BINDING_MASK
Definition: Wasm.h:278
bool isHidden() const
Definition: Wasm.h:89
const wasm::WasmGlobalType * GlobalType
Definition: Wasm.h:47
const wasm::WasmSignature * Signature
Definition: Wasm.h:49
OStream & operator<<(OStream &OS, const DataRefImpl &D)
Definition: SymbolicFile.h:47
bool isUndefined() const
Definition: Wasm.h:69
ArrayRef< wasm::WasmEvent > events() const
Definition: Wasm.h:139
Lightweight error class with error context and mandatory checking.
Definition: Error.h:158
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:46
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
static FeatureBitset getFeatures(StringRef CPU, StringRef FS, ArrayRef< SubtargetFeatureKV > ProcDesc, ArrayRef< SubtargetFeatureKV > ProcFeatures)
bool isWasm() const
Definition: Binary.h:121
bool isBindingWeak() const
Definition: Wasm.h:73
This is a value type class that represents a single section in the list of sections in the object fil...
Definition: ObjectFile.h:81
void print(raw_ostream &Out) const