Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame^] | 1 | // Copyright 2015 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/signature.h" |
| 6 | |
| 7 | #include "src/handles.h" |
| 8 | #include "src/v8.h" |
| 9 | #include "src/zone-containers.h" |
| 10 | |
| 11 | #include "src/wasm/ast-decoder.h" |
| 12 | #include "src/wasm/encoder.h" |
| 13 | #include "src/wasm/wasm-module.h" |
| 14 | #include "src/wasm/wasm-opcodes.h" |
| 15 | |
| 16 | #include "src/v8memory.h" |
| 17 | |
| 18 | namespace v8 { |
| 19 | namespace internal { |
| 20 | namespace wasm { |
| 21 | |
| 22 | /*TODO: add error cases for adding too many locals, too many functions and bad |
| 23 | indices in body */ |
| 24 | |
| 25 | namespace { |
| 26 | void EmitUint8(byte** b, uint8_t x) { |
| 27 | Memory::uint8_at(*b) = x; |
| 28 | *b += 1; |
| 29 | } |
| 30 | |
| 31 | |
| 32 | void EmitUint16(byte** b, uint16_t x) { |
| 33 | Memory::uint16_at(*b) = x; |
| 34 | *b += 2; |
| 35 | } |
| 36 | |
| 37 | |
| 38 | void EmitUint32(byte** b, uint32_t x) { |
| 39 | Memory::uint32_at(*b) = x; |
| 40 | *b += 4; |
| 41 | } |
| 42 | |
| 43 | |
| 44 | void EmitVarInt(byte** b, size_t val) { |
| 45 | while (true) { |
| 46 | size_t next = val >> 7; |
| 47 | byte out = static_cast<byte>(val & 0x7f); |
| 48 | if (next) { |
| 49 | *((*b)++) = 0x80 | out; |
| 50 | val = next; |
| 51 | } else { |
| 52 | *((*b)++) = out; |
| 53 | break; |
| 54 | } |
| 55 | } |
| 56 | } |
| 57 | } // namespace |
| 58 | |
| 59 | |
| 60 | struct WasmFunctionBuilder::Type { |
| 61 | bool param_; |
| 62 | LocalType type_; |
| 63 | }; |
| 64 | |
| 65 | |
| 66 | WasmFunctionBuilder::WasmFunctionBuilder(Zone* zone) |
| 67 | : return_type_(kAstI32), |
| 68 | locals_(zone), |
| 69 | exported_(0), |
| 70 | external_(0), |
| 71 | body_(zone), |
| 72 | local_indices_(zone), |
| 73 | name_(zone) {} |
| 74 | |
| 75 | |
| 76 | uint16_t WasmFunctionBuilder::AddParam(LocalType type) { |
| 77 | return AddVar(type, true); |
| 78 | } |
| 79 | |
| 80 | |
| 81 | uint16_t WasmFunctionBuilder::AddLocal(LocalType type) { |
| 82 | return AddVar(type, false); |
| 83 | } |
| 84 | |
| 85 | |
| 86 | uint16_t WasmFunctionBuilder::AddVar(LocalType type, bool param) { |
| 87 | locals_.push_back({param, type}); |
| 88 | return static_cast<uint16_t>(locals_.size() - 1); |
| 89 | } |
| 90 | |
| 91 | |
| 92 | void WasmFunctionBuilder::ReturnType(LocalType type) { return_type_ = type; } |
| 93 | |
| 94 | |
| 95 | void WasmFunctionBuilder::EmitCode(const byte* code, uint32_t code_size) { |
| 96 | EmitCode(code, code_size, nullptr, 0); |
| 97 | } |
| 98 | |
| 99 | |
| 100 | void WasmFunctionBuilder::EmitCode(const byte* code, uint32_t code_size, |
| 101 | const uint32_t* local_indices, |
| 102 | uint32_t indices_size) { |
| 103 | size_t size = body_.size(); |
| 104 | for (size_t i = 0; i < code_size; i++) { |
| 105 | body_.push_back(code[i]); |
| 106 | } |
| 107 | for (size_t i = 0; i < indices_size; i++) { |
| 108 | local_indices_.push_back(local_indices[i] + static_cast<uint32_t>(size)); |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | |
| 113 | void WasmFunctionBuilder::Emit(WasmOpcode opcode) { |
| 114 | body_.push_back(static_cast<byte>(opcode)); |
| 115 | } |
| 116 | |
| 117 | |
| 118 | void WasmFunctionBuilder::EmitWithU8(WasmOpcode opcode, const byte immediate) { |
| 119 | body_.push_back(static_cast<byte>(opcode)); |
| 120 | body_.push_back(immediate); |
| 121 | } |
| 122 | |
| 123 | |
| 124 | void WasmFunctionBuilder::EmitWithLocal(WasmOpcode opcode) { |
| 125 | body_.push_back(static_cast<byte>(opcode)); |
| 126 | local_indices_.push_back(static_cast<uint32_t>(body_.size()) - 1); |
| 127 | } |
| 128 | |
| 129 | |
| 130 | uint32_t WasmFunctionBuilder::EmitEditableImmediate(const byte immediate) { |
| 131 | body_.push_back(immediate); |
| 132 | return static_cast<uint32_t>(body_.size()) - 1; |
| 133 | } |
| 134 | |
| 135 | |
| 136 | void WasmFunctionBuilder::EditImmediate(uint32_t offset, const byte immediate) { |
| 137 | DCHECK(offset < body_.size()); |
| 138 | body_[offset] = immediate; |
| 139 | } |
| 140 | |
| 141 | |
| 142 | void WasmFunctionBuilder::Exported(uint8_t flag) { exported_ = flag; } |
| 143 | |
| 144 | |
| 145 | void WasmFunctionBuilder::External(uint8_t flag) { external_ = flag; } |
| 146 | |
| 147 | void WasmFunctionBuilder::SetName(const unsigned char* name, int name_length) { |
| 148 | name_.clear(); |
| 149 | if (name_length > 0) { |
| 150 | for (int i = 0; i < name_length; i++) { |
| 151 | name_.push_back(*(name + i)); |
| 152 | } |
| 153 | name_.push_back('\0'); |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | |
| 158 | WasmFunctionEncoder* WasmFunctionBuilder::Build(Zone* zone, |
| 159 | WasmModuleBuilder* mb) const { |
| 160 | WasmFunctionEncoder* e = |
| 161 | new (zone) WasmFunctionEncoder(zone, return_type_, exported_, external_); |
| 162 | uint16_t* var_index = zone->NewArray<uint16_t>(locals_.size()); |
| 163 | IndexVars(e, var_index); |
| 164 | if (body_.size() > 0) { |
| 165 | // TODO(titzer): iterate over local indexes, not the bytes. |
| 166 | const byte* start = &body_[0]; |
| 167 | const byte* end = start + body_.size(); |
| 168 | size_t local_index = 0; |
| 169 | for (size_t i = 0; i < body_.size();) { |
| 170 | if (local_index < local_indices_.size() && |
| 171 | i == local_indices_[local_index]) { |
| 172 | int length = 0; |
| 173 | uint32_t index; |
| 174 | ReadUnsignedLEB128Operand(start + i, end, &length, &index); |
| 175 | uint16_t new_index = var_index[index]; |
| 176 | const std::vector<uint8_t>& index_vec = UnsignedLEB128From(new_index); |
| 177 | for (size_t j = 0; j < index_vec.size(); j++) { |
| 178 | e->body_.push_back(index_vec.at(j)); |
| 179 | } |
| 180 | i += length; |
| 181 | local_index++; |
| 182 | } else { |
| 183 | e->body_.push_back(*(start + i)); |
| 184 | i++; |
| 185 | } |
| 186 | } |
| 187 | } |
| 188 | FunctionSig::Builder sig(zone, return_type_ == kAstStmt ? 0 : 1, |
| 189 | e->params_.size()); |
| 190 | if (return_type_ != kAstStmt) { |
| 191 | sig.AddReturn(static_cast<LocalType>(return_type_)); |
| 192 | } |
| 193 | for (size_t i = 0; i < e->params_.size(); i++) { |
| 194 | sig.AddParam(static_cast<LocalType>(e->params_[i])); |
| 195 | } |
| 196 | e->signature_index_ = mb->AddSignature(sig.Build()); |
| 197 | e->name_.insert(e->name_.begin(), name_.begin(), name_.end()); |
| 198 | return e; |
| 199 | } |
| 200 | |
| 201 | |
| 202 | void WasmFunctionBuilder::IndexVars(WasmFunctionEncoder* e, |
| 203 | uint16_t* var_index) const { |
| 204 | uint16_t param = 0; |
| 205 | uint16_t int32 = 0; |
| 206 | uint16_t int64 = 0; |
| 207 | uint16_t float32 = 0; |
| 208 | uint16_t float64 = 0; |
| 209 | for (size_t i = 0; i < locals_.size(); i++) { |
| 210 | if (locals_.at(i).param_) { |
| 211 | param++; |
| 212 | } else if (locals_.at(i).type_ == kAstI32) { |
| 213 | int32++; |
| 214 | } else if (locals_.at(i).type_ == kAstI64) { |
| 215 | int64++; |
| 216 | } else if (locals_.at(i).type_ == kAstF32) { |
| 217 | float32++; |
| 218 | } else if (locals_.at(i).type_ == kAstF64) { |
| 219 | float64++; |
| 220 | } |
| 221 | } |
| 222 | e->local_int32_count_ = int32; |
| 223 | e->local_int64_count_ = int64; |
| 224 | e->local_float32_count_ = float32; |
| 225 | e->local_float64_count_ = float64; |
| 226 | float64 = param + int32 + int64 + float32; |
| 227 | float32 = param + int32 + int64; |
| 228 | int64 = param + int32; |
| 229 | int32 = param; |
| 230 | param = 0; |
| 231 | for (size_t i = 0; i < locals_.size(); i++) { |
| 232 | if (locals_.at(i).param_) { |
| 233 | e->params_.push_back(locals_.at(i).type_); |
| 234 | var_index[i] = param++; |
| 235 | } else if (locals_.at(i).type_ == kAstI32) { |
| 236 | var_index[i] = int32++; |
| 237 | } else if (locals_.at(i).type_ == kAstI64) { |
| 238 | var_index[i] = int64++; |
| 239 | } else if (locals_.at(i).type_ == kAstF32) { |
| 240 | var_index[i] = float32++; |
| 241 | } else if (locals_.at(i).type_ == kAstF64) { |
| 242 | var_index[i] = float64++; |
| 243 | } |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | |
| 248 | WasmFunctionEncoder::WasmFunctionEncoder(Zone* zone, LocalType return_type, |
| 249 | bool exported, bool external) |
| 250 | : params_(zone), |
| 251 | exported_(exported), |
| 252 | external_(external), |
| 253 | body_(zone), |
| 254 | name_(zone) {} |
| 255 | |
| 256 | |
| 257 | uint32_t WasmFunctionEncoder::HeaderSize() const { |
| 258 | uint32_t size = 3; |
| 259 | if (HasLocals()) size += 8; |
| 260 | if (!external_) size += 2; |
| 261 | if (HasName()) size += 4; |
| 262 | return size; |
| 263 | } |
| 264 | |
| 265 | |
| 266 | uint32_t WasmFunctionEncoder::BodySize(void) const { |
| 267 | return external_ ? 0 : static_cast<uint32_t>(body_.size()); |
| 268 | } |
| 269 | |
| 270 | |
| 271 | uint32_t WasmFunctionEncoder::NameSize() const { |
| 272 | return exported_ ? static_cast<uint32_t>(name_.size()) : 0; |
| 273 | } |
| 274 | |
| 275 | |
| 276 | void WasmFunctionEncoder::Serialize(byte* buffer, byte** header, |
| 277 | byte** body) const { |
| 278 | uint8_t decl_bits = (exported_ ? kDeclFunctionExport : 0) | |
| 279 | (external_ ? kDeclFunctionImport : 0) | |
| 280 | (HasLocals() ? kDeclFunctionLocals : 0) | |
| 281 | (HasName() ? kDeclFunctionName : 0); |
| 282 | |
| 283 | EmitUint8(header, decl_bits); |
| 284 | EmitUint16(header, signature_index_); |
| 285 | |
| 286 | if (HasName()) { |
| 287 | uint32_t name_offset = static_cast<uint32_t>(*body - buffer); |
| 288 | EmitUint32(header, name_offset); |
| 289 | std::memcpy(*body, &name_[0], name_.size()); |
| 290 | (*body) += name_.size(); |
| 291 | } |
| 292 | |
| 293 | if (HasLocals()) { |
| 294 | EmitUint16(header, local_int32_count_); |
| 295 | EmitUint16(header, local_int64_count_); |
| 296 | EmitUint16(header, local_float32_count_); |
| 297 | EmitUint16(header, local_float64_count_); |
| 298 | } |
| 299 | |
| 300 | if (!external_) { |
| 301 | EmitUint16(header, static_cast<uint16_t>(body_.size())); |
| 302 | if (body_.size() > 0) { |
| 303 | std::memcpy(*header, &body_[0], body_.size()); |
| 304 | (*header) += body_.size(); |
| 305 | } |
| 306 | } |
| 307 | } |
| 308 | |
| 309 | |
| 310 | WasmDataSegmentEncoder::WasmDataSegmentEncoder(Zone* zone, const byte* data, |
| 311 | uint32_t size, uint32_t dest) |
| 312 | : data_(zone), dest_(dest) { |
| 313 | for (size_t i = 0; i < size; i++) { |
| 314 | data_.push_back(data[i]); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | |
| 319 | uint32_t WasmDataSegmentEncoder::HeaderSize() const { |
| 320 | static const int kDataSegmentSize = 13; |
| 321 | return kDataSegmentSize; |
| 322 | } |
| 323 | |
| 324 | |
| 325 | uint32_t WasmDataSegmentEncoder::BodySize() const { |
| 326 | return static_cast<uint32_t>(data_.size()); |
| 327 | } |
| 328 | |
| 329 | |
| 330 | void WasmDataSegmentEncoder::Serialize(byte* buffer, byte** header, |
| 331 | byte** body) const { |
| 332 | uint32_t body_offset = static_cast<uint32_t>(*body - buffer); |
| 333 | EmitUint32(header, dest_); |
| 334 | EmitUint32(header, body_offset); |
| 335 | EmitUint32(header, static_cast<uint32_t>(data_.size())); |
| 336 | EmitUint8(header, 1); // init |
| 337 | |
| 338 | std::memcpy(*body, &data_[0], data_.size()); |
| 339 | (*body) += data_.size(); |
| 340 | } |
| 341 | |
| 342 | |
| 343 | WasmModuleBuilder::WasmModuleBuilder(Zone* zone) |
| 344 | : zone_(zone), |
| 345 | signatures_(zone), |
| 346 | functions_(zone), |
| 347 | data_segments_(zone), |
| 348 | indirect_functions_(zone), |
| 349 | globals_(zone), |
| 350 | signature_map_(zone) {} |
| 351 | |
| 352 | |
| 353 | uint16_t WasmModuleBuilder::AddFunction() { |
| 354 | functions_.push_back(new (zone_) WasmFunctionBuilder(zone_)); |
| 355 | return static_cast<uint16_t>(functions_.size() - 1); |
| 356 | } |
| 357 | |
| 358 | |
| 359 | WasmFunctionBuilder* WasmModuleBuilder::FunctionAt(size_t index) { |
| 360 | if (functions_.size() > index) { |
| 361 | return functions_.at(index); |
| 362 | } else { |
| 363 | return nullptr; |
| 364 | } |
| 365 | } |
| 366 | |
| 367 | |
| 368 | void WasmModuleBuilder::AddDataSegment(WasmDataSegmentEncoder* data) { |
| 369 | data_segments_.push_back(data); |
| 370 | } |
| 371 | |
| 372 | |
| 373 | int WasmModuleBuilder::CompareFunctionSigs::operator()(FunctionSig* a, |
| 374 | FunctionSig* b) const { |
| 375 | if (a->return_count() < b->return_count()) return -1; |
| 376 | if (a->return_count() > b->return_count()) return 1; |
| 377 | if (a->parameter_count() < b->parameter_count()) return -1; |
| 378 | if (a->parameter_count() > b->parameter_count()) return 1; |
| 379 | for (size_t r = 0; r < a->return_count(); r++) { |
| 380 | if (a->GetReturn(r) < b->GetReturn(r)) return -1; |
| 381 | if (a->GetReturn(r) > b->GetReturn(r)) return 1; |
| 382 | } |
| 383 | for (size_t p = 0; p < a->parameter_count(); p++) { |
| 384 | if (a->GetParam(p) < b->GetParam(p)) return -1; |
| 385 | if (a->GetParam(p) > b->GetParam(p)) return 1; |
| 386 | } |
| 387 | return 0; |
| 388 | } |
| 389 | |
| 390 | |
| 391 | uint16_t WasmModuleBuilder::AddSignature(FunctionSig* sig) { |
| 392 | SignatureMap::iterator pos = signature_map_.find(sig); |
| 393 | if (pos != signature_map_.end()) { |
| 394 | return pos->second; |
| 395 | } else { |
| 396 | uint16_t index = static_cast<uint16_t>(signatures_.size()); |
| 397 | signature_map_[sig] = index; |
| 398 | signatures_.push_back(sig); |
| 399 | return index; |
| 400 | } |
| 401 | } |
| 402 | |
| 403 | |
| 404 | void WasmModuleBuilder::AddIndirectFunction(uint16_t index) { |
| 405 | indirect_functions_.push_back(index); |
| 406 | } |
| 407 | |
| 408 | |
| 409 | WasmModuleWriter* WasmModuleBuilder::Build(Zone* zone) { |
| 410 | WasmModuleWriter* writer = new (zone) WasmModuleWriter(zone); |
| 411 | for (auto function : functions_) { |
| 412 | writer->functions_.push_back(function->Build(zone, this)); |
| 413 | } |
| 414 | for (auto segment : data_segments_) { |
| 415 | writer->data_segments_.push_back(segment); |
| 416 | } |
| 417 | for (auto sig : signatures_) { |
| 418 | writer->signatures_.push_back(sig); |
| 419 | } |
| 420 | for (auto index : indirect_functions_) { |
| 421 | writer->indirect_functions_.push_back(index); |
| 422 | } |
| 423 | for (auto global : globals_) { |
| 424 | writer->globals_.push_back(global); |
| 425 | } |
| 426 | return writer; |
| 427 | } |
| 428 | |
| 429 | |
| 430 | uint32_t WasmModuleBuilder::AddGlobal(MachineType type, bool exported) { |
| 431 | globals_.push_back(std::make_pair(type, exported)); |
| 432 | return static_cast<uint32_t>(globals_.size() - 1); |
| 433 | } |
| 434 | |
| 435 | |
| 436 | WasmModuleWriter::WasmModuleWriter(Zone* zone) |
| 437 | : functions_(zone), |
| 438 | data_segments_(zone), |
| 439 | signatures_(zone), |
| 440 | indirect_functions_(zone), |
| 441 | globals_(zone) {} |
| 442 | |
| 443 | |
| 444 | struct Sizes { |
| 445 | size_t header_size; |
| 446 | size_t body_size; |
| 447 | |
| 448 | size_t total() { return header_size + body_size; } |
| 449 | |
| 450 | void Add(size_t header, size_t body) { |
| 451 | header_size += header; |
| 452 | body_size += body; |
| 453 | } |
| 454 | |
| 455 | void AddSection(size_t size) { |
| 456 | if (size > 0) { |
| 457 | Add(1, 0); |
| 458 | while (size > 0) { |
| 459 | Add(1, 0); |
| 460 | size = size >> 7; |
| 461 | } |
| 462 | } |
| 463 | } |
| 464 | }; |
| 465 | |
| 466 | |
| 467 | WasmModuleIndex* WasmModuleWriter::WriteTo(Zone* zone) const { |
| 468 | Sizes sizes = {0, 0}; |
| 469 | |
| 470 | sizes.Add(1, 0); |
| 471 | sizes.Add(kDeclMemorySize, 0); |
| 472 | |
| 473 | sizes.AddSection(signatures_.size()); |
| 474 | for (auto sig : signatures_) { |
| 475 | sizes.Add(2 + sig->parameter_count(), 0); |
| 476 | } |
| 477 | |
| 478 | sizes.AddSection(globals_.size()); |
| 479 | if (globals_.size() > 0) { |
| 480 | sizes.Add(kDeclGlobalSize * globals_.size(), 0); |
| 481 | } |
| 482 | |
| 483 | sizes.AddSection(functions_.size()); |
| 484 | for (auto function : functions_) { |
| 485 | sizes.Add(function->HeaderSize() + function->BodySize(), |
| 486 | function->NameSize()); |
| 487 | } |
| 488 | |
| 489 | sizes.AddSection(data_segments_.size()); |
| 490 | for (auto segment : data_segments_) { |
| 491 | sizes.Add(segment->HeaderSize(), segment->BodySize()); |
| 492 | } |
| 493 | |
| 494 | sizes.AddSection(indirect_functions_.size()); |
| 495 | sizes.Add(2 * static_cast<uint32_t>(indirect_functions_.size()), 0); |
| 496 | |
| 497 | if (sizes.body_size > 0) sizes.Add(1, 0); |
| 498 | |
| 499 | ZoneVector<uint8_t> buffer_vector(sizes.total(), zone); |
| 500 | byte* buffer = &buffer_vector[0]; |
| 501 | byte* header = buffer; |
| 502 | byte* body = buffer + sizes.header_size; |
| 503 | |
| 504 | // -- emit memory declaration ------------------------------------------------ |
| 505 | EmitUint8(&header, kDeclMemory); |
| 506 | EmitUint8(&header, 16); // min memory size |
| 507 | EmitUint8(&header, 16); // max memory size |
| 508 | EmitUint8(&header, 0); // memory export |
| 509 | |
| 510 | // -- emit globals ----------------------------------------------------------- |
| 511 | if (globals_.size() > 0) { |
| 512 | EmitUint8(&header, kDeclGlobals); |
| 513 | EmitVarInt(&header, globals_.size()); |
| 514 | |
| 515 | for (auto global : globals_) { |
| 516 | EmitUint32(&header, 0); |
| 517 | EmitUint8(&header, WasmOpcodes::MemTypeCodeFor(global.first)); |
| 518 | EmitUint8(&header, global.second); |
| 519 | } |
| 520 | } |
| 521 | |
| 522 | // -- emit signatures -------------------------------------------------------- |
| 523 | if (signatures_.size() > 0) { |
| 524 | EmitUint8(&header, kDeclSignatures); |
| 525 | EmitVarInt(&header, signatures_.size()); |
| 526 | |
| 527 | for (FunctionSig* sig : signatures_) { |
| 528 | EmitUint8(&header, static_cast<byte>(sig->parameter_count())); |
| 529 | if (sig->return_count() > 0) { |
| 530 | EmitUint8(&header, WasmOpcodes::LocalTypeCodeFor(sig->GetReturn())); |
| 531 | } else { |
| 532 | EmitUint8(&header, kLocalVoid); |
| 533 | } |
| 534 | for (size_t j = 0; j < sig->parameter_count(); j++) { |
| 535 | EmitUint8(&header, WasmOpcodes::LocalTypeCodeFor(sig->GetParam(j))); |
| 536 | } |
| 537 | } |
| 538 | } |
| 539 | |
| 540 | // -- emit functions --------------------------------------------------------- |
| 541 | if (functions_.size() > 0) { |
| 542 | EmitUint8(&header, kDeclFunctions); |
| 543 | EmitVarInt(&header, functions_.size()); |
| 544 | |
| 545 | for (auto func : functions_) { |
| 546 | func->Serialize(buffer, &header, &body); |
| 547 | } |
| 548 | } |
| 549 | |
| 550 | // -- emit data segments ----------------------------------------------------- |
| 551 | if (data_segments_.size() > 0) { |
| 552 | EmitUint8(&header, kDeclDataSegments); |
| 553 | EmitVarInt(&header, data_segments_.size()); |
| 554 | |
| 555 | for (auto segment : data_segments_) { |
| 556 | segment->Serialize(buffer, &header, &body); |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | // -- emit function table ---------------------------------------------------- |
| 561 | if (indirect_functions_.size() > 0) { |
| 562 | EmitUint8(&header, kDeclFunctionTable); |
| 563 | EmitVarInt(&header, indirect_functions_.size()); |
| 564 | |
| 565 | for (auto index : indirect_functions_) { |
| 566 | EmitUint16(&header, index); |
| 567 | } |
| 568 | } |
| 569 | |
| 570 | if (sizes.body_size > 0) EmitUint8(&header, kDeclEnd); |
| 571 | |
| 572 | return new (zone) WasmModuleIndex(buffer, buffer + sizes.total()); |
| 573 | } |
| 574 | |
| 575 | |
| 576 | std::vector<uint8_t> UnsignedLEB128From(uint32_t result) { |
| 577 | std::vector<uint8_t> output; |
| 578 | uint8_t next = 0; |
| 579 | int shift = 0; |
| 580 | do { |
| 581 | next = static_cast<uint8_t>(result >> shift); |
| 582 | if (((result >> shift) & 0xFFFFFF80) != 0) { |
| 583 | next = next | 0x80; |
| 584 | } |
| 585 | output.push_back(next); |
| 586 | shift += 7; |
| 587 | } while ((next & 0x80) != 0); |
| 588 | return output; |
| 589 | } |
| 590 | } // namespace wasm |
| 591 | } // namespace internal |
| 592 | } // namespace v8 |