| // Copyright 2015 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "src/wasm/wasm-module-builder.h" |
| |
| #include "src/base/memory.h" |
| #include "src/codegen/signature.h" |
| #include "src/handles/handles.h" |
| #include "src/init/v8.h" |
| #include "src/objects/objects-inl.h" |
| #include "src/wasm/function-body-decoder.h" |
| #include "src/wasm/leb-helper.h" |
| #include "src/wasm/wasm-constants.h" |
| #include "src/wasm/wasm-module.h" |
| #include "src/zone/zone-containers.h" |
| |
| namespace v8 { |
| namespace internal { |
| namespace wasm { |
| |
| namespace { |
| |
| // Emit a section code and the size as a padded varint that can be patched |
| // later. |
| size_t EmitSection(SectionCode code, ZoneBuffer* buffer) { |
| // Emit the section code. |
| buffer->write_u8(code); |
| |
| // Emit a placeholder for the length. |
| return buffer->reserve_u32v(); |
| } |
| |
| // Patch the size of a section after it's finished. |
| void FixupSection(ZoneBuffer* buffer, size_t start) { |
| buffer->patch_u32v(start, static_cast<uint32_t>(buffer->offset() - start - |
| kPaddedVarInt32Size)); |
| } |
| |
| } // namespace |
| |
| WasmFunctionBuilder::WasmFunctionBuilder(WasmModuleBuilder* builder) |
| : builder_(builder), |
| locals_(builder->zone()), |
| signature_index_(0), |
| func_index_(static_cast<uint32_t>(builder->functions_.size())), |
| body_(builder->zone(), 256), |
| i32_temps_(builder->zone()), |
| i64_temps_(builder->zone()), |
| f32_temps_(builder->zone()), |
| f64_temps_(builder->zone()), |
| direct_calls_(builder->zone()), |
| asm_offsets_(builder->zone(), 8) {} |
| |
| void WasmFunctionBuilder::EmitByte(byte val) { body_.write_u8(val); } |
| |
| void WasmFunctionBuilder::EmitI32V(int32_t val) { body_.write_i32v(val); } |
| |
| void WasmFunctionBuilder::EmitU32V(uint32_t val) { body_.write_u32v(val); } |
| |
| void WasmFunctionBuilder::SetSignature(FunctionSig* sig) { |
| DCHECK(!locals_.has_sig()); |
| locals_.set_sig(sig); |
| signature_index_ = builder_->AddSignature(sig); |
| } |
| |
| uint32_t WasmFunctionBuilder::AddLocal(ValueType type) { |
| DCHECK(locals_.has_sig()); |
| return locals_.AddLocals(1, type); |
| } |
| |
| void WasmFunctionBuilder::EmitGetLocal(uint32_t local_index) { |
| EmitWithU32V(kExprLocalGet, local_index); |
| } |
| |
| void WasmFunctionBuilder::EmitSetLocal(uint32_t local_index) { |
| EmitWithU32V(kExprLocalSet, local_index); |
| } |
| |
| void WasmFunctionBuilder::EmitTeeLocal(uint32_t local_index) { |
| EmitWithU32V(kExprLocalTee, local_index); |
| } |
| |
| void WasmFunctionBuilder::EmitCode(const byte* code, uint32_t code_size) { |
| body_.write(code, code_size); |
| } |
| |
| void WasmFunctionBuilder::Emit(WasmOpcode opcode) { body_.write_u8(opcode); } |
| |
| void WasmFunctionBuilder::EmitWithPrefix(WasmOpcode opcode) { |
| DCHECK_NE(0, opcode & 0xff00); |
| body_.write_u8(opcode >> 8); |
| if ((opcode >> 8) == WasmOpcode::kSimdPrefix) { |
| // SIMD opcodes are LEB encoded |
| body_.write_u32v(opcode & 0xff); |
| } else { |
| body_.write_u8(opcode); |
| } |
| } |
| |
| void WasmFunctionBuilder::EmitWithU8(WasmOpcode opcode, const byte immediate) { |
| body_.write_u8(opcode); |
| body_.write_u8(immediate); |
| } |
| |
| void WasmFunctionBuilder::EmitWithU8U8(WasmOpcode opcode, const byte imm1, |
| const byte imm2) { |
| body_.write_u8(opcode); |
| body_.write_u8(imm1); |
| body_.write_u8(imm2); |
| } |
| |
| void WasmFunctionBuilder::EmitWithI32V(WasmOpcode opcode, int32_t immediate) { |
| body_.write_u8(opcode); |
| body_.write_i32v(immediate); |
| } |
| |
| void WasmFunctionBuilder::EmitWithU32V(WasmOpcode opcode, uint32_t immediate) { |
| body_.write_u8(opcode); |
| body_.write_u32v(immediate); |
| } |
| |
| namespace { |
| void WriteValueType(ZoneBuffer* buffer, const ValueType& type) { |
| buffer->write_u8(type.value_type_code()); |
| if (type.encoding_needs_heap_type()) { |
| buffer->write_i32v(type.heap_type().code()); |
| } |
| if (type.is_rtt()) { |
| if (type.has_depth()) buffer->write_u32v(type.depth()); |
| buffer->write_u32v(type.ref_index()); |
| } |
| } |
| } // namespace |
| |
| void WasmFunctionBuilder::EmitValueType(ValueType type) { |
| WriteValueType(&body_, type); |
| } |
| |
| void WasmFunctionBuilder::EmitI32Const(int32_t value) { |
| EmitWithI32V(kExprI32Const, value); |
| } |
| |
| void WasmFunctionBuilder::EmitI64Const(int64_t value) { |
| body_.write_u8(kExprI64Const); |
| body_.write_i64v(value); |
| } |
| |
| void WasmFunctionBuilder::EmitF32Const(float value) { |
| body_.write_u8(kExprF32Const); |
| body_.write_f32(value); |
| } |
| |
| void WasmFunctionBuilder::EmitF64Const(double value) { |
| body_.write_u8(kExprF64Const); |
| body_.write_f64(value); |
| } |
| |
| void WasmFunctionBuilder::EmitDirectCallIndex(uint32_t index) { |
| DirectCallIndex call; |
| call.offset = body_.size(); |
| call.direct_index = index; |
| direct_calls_.push_back(call); |
| byte placeholder_bytes[kMaxVarInt32Size] = {0}; |
| EmitCode(placeholder_bytes, arraysize(placeholder_bytes)); |
| } |
| |
| void WasmFunctionBuilder::SetName(base::Vector<const char> name) { |
| name_ = name; |
| } |
| |
| void WasmFunctionBuilder::AddAsmWasmOffset(size_t call_position, |
| size_t to_number_position) { |
| // We only want to emit one mapping per byte offset. |
| DCHECK(asm_offsets_.size() == 0 || body_.size() > last_asm_byte_offset_); |
| |
| DCHECK_LE(body_.size(), kMaxUInt32); |
| uint32_t byte_offset = static_cast<uint32_t>(body_.size()); |
| asm_offsets_.write_u32v(byte_offset - last_asm_byte_offset_); |
| last_asm_byte_offset_ = byte_offset; |
| |
| DCHECK_GE(std::numeric_limits<uint32_t>::max(), call_position); |
| uint32_t call_position_u32 = static_cast<uint32_t>(call_position); |
| asm_offsets_.write_i32v(call_position_u32 - last_asm_source_position_); |
| |
| DCHECK_GE(std::numeric_limits<uint32_t>::max(), to_number_position); |
| uint32_t to_number_position_u32 = static_cast<uint32_t>(to_number_position); |
| asm_offsets_.write_i32v(to_number_position_u32 - call_position_u32); |
| last_asm_source_position_ = to_number_position_u32; |
| } |
| |
| void WasmFunctionBuilder::SetAsmFunctionStartPosition( |
| size_t function_position) { |
| DCHECK_EQ(0, asm_func_start_source_position_); |
| DCHECK_GE(std::numeric_limits<uint32_t>::max(), function_position); |
| uint32_t function_position_u32 = static_cast<uint32_t>(function_position); |
| // Must be called before emitting any asm.js source position. |
| DCHECK_EQ(0, asm_offsets_.size()); |
| asm_func_start_source_position_ = function_position_u32; |
| last_asm_source_position_ = function_position_u32; |
| } |
| |
| void WasmFunctionBuilder::SetCompilationHint( |
| WasmCompilationHintStrategy strategy, WasmCompilationHintTier baseline, |
| WasmCompilationHintTier top_tier) { |
| uint8_t hint_byte = static_cast<uint8_t>(strategy) | |
| static_cast<uint8_t>(baseline) << 2 | |
| static_cast<uint8_t>(top_tier) << 4; |
| DCHECK_NE(hint_byte, kNoCompilationHint); |
| hint_ = hint_byte; |
| } |
| |
| void WasmFunctionBuilder::DeleteCodeAfter(size_t position) { |
| DCHECK_LE(position, body_.size()); |
| body_.Truncate(position); |
| } |
| |
| void WasmFunctionBuilder::WriteSignature(ZoneBuffer* buffer) const { |
| buffer->write_u32v(signature_index_); |
| } |
| |
| void WasmFunctionBuilder::WriteBody(ZoneBuffer* buffer) const { |
| size_t locals_size = locals_.Size(); |
| buffer->write_size(locals_size + body_.size()); |
| buffer->EnsureSpace(locals_size); |
| byte** ptr = buffer->pos_ptr(); |
| locals_.Emit(*ptr); |
| (*ptr) += locals_size; // UGLY: manual bump of position pointer |
| if (body_.size() > 0) { |
| size_t base = buffer->offset(); |
| buffer->write(body_.begin(), body_.size()); |
| for (DirectCallIndex call : direct_calls_) { |
| buffer->patch_u32v( |
| base + call.offset, |
| call.direct_index + |
| static_cast<uint32_t>(builder_->function_imports_.size())); |
| } |
| } |
| } |
| |
| void WasmFunctionBuilder::WriteAsmWasmOffsetTable(ZoneBuffer* buffer) const { |
| if (asm_func_start_source_position_ == 0 && asm_offsets_.size() == 0) { |
| buffer->write_size(0); |
| return; |
| } |
| size_t locals_enc_size = LEBHelper::sizeof_u32v(locals_.Size()); |
| size_t func_start_size = |
| LEBHelper::sizeof_u32v(asm_func_start_source_position_); |
| buffer->write_size(asm_offsets_.size() + locals_enc_size + func_start_size); |
| // Offset of the recorded byte offsets. |
| DCHECK_GE(kMaxUInt32, locals_.Size()); |
| buffer->write_u32v(static_cast<uint32_t>(locals_.Size())); |
| // Start position of the function. |
| buffer->write_u32v(asm_func_start_source_position_); |
| buffer->write(asm_offsets_.begin(), asm_offsets_.size()); |
| } |
| |
| WasmModuleBuilder::WasmModuleBuilder(Zone* zone) |
| : zone_(zone), |
| types_(zone), |
| function_imports_(zone), |
| global_imports_(zone), |
| exports_(zone), |
| functions_(zone), |
| tables_(zone), |
| data_segments_(zone), |
| element_segments_(zone), |
| globals_(zone), |
| exceptions_(zone), |
| signature_map_(zone), |
| start_function_index_(-1), |
| min_memory_size_(16), |
| max_memory_size_(0), |
| has_max_memory_size_(false), |
| has_shared_memory_(false) {} |
| |
| WasmFunctionBuilder* WasmModuleBuilder::AddFunction(FunctionSig* sig) { |
| functions_.push_back(zone_->New<WasmFunctionBuilder>(this)); |
| // Add the signature if one was provided here. |
| if (sig) functions_.back()->SetSignature(sig); |
| return functions_.back(); |
| } |
| |
| void WasmModuleBuilder::AddDataSegment(const byte* data, uint32_t size, |
| uint32_t dest) { |
| data_segments_.push_back({ZoneVector<byte>(zone()), dest}); |
| ZoneVector<byte>& vec = data_segments_.back().data; |
| for (uint32_t i = 0; i < size; i++) { |
| vec.push_back(data[i]); |
| } |
| } |
| |
| uint32_t WasmModuleBuilder::AddSignature(FunctionSig* sig) { |
| auto sig_entry = signature_map_.find(*sig); |
| if (sig_entry != signature_map_.end()) return sig_entry->second; |
| uint32_t index = static_cast<uint32_t>(types_.size()); |
| signature_map_.emplace(*sig, index); |
| types_.push_back(Type(sig)); |
| return index; |
| } |
| |
| uint32_t WasmModuleBuilder::AddException(FunctionSig* type) { |
| DCHECK_EQ(0, type->return_count()); |
| int type_index = AddSignature(type); |
| uint32_t except_index = static_cast<uint32_t>(exceptions_.size()); |
| exceptions_.push_back(type_index); |
| return except_index; |
| } |
| |
| uint32_t WasmModuleBuilder::AddStructType(StructType* type) { |
| uint32_t index = static_cast<uint32_t>(types_.size()); |
| types_.push_back(Type(type)); |
| return index; |
| } |
| |
| uint32_t WasmModuleBuilder::AddArrayType(ArrayType* type) { |
| uint32_t index = static_cast<uint32_t>(types_.size()); |
| types_.push_back(Type(type)); |
| return index; |
| } |
| |
| // static |
| const uint32_t WasmModuleBuilder::kNullIndex = |
| std::numeric_limits<uint32_t>::max(); |
| |
| uint32_t WasmModuleBuilder::IncreaseTableMinSize(uint32_t table_index, |
| uint32_t count) { |
| DCHECK_LT(table_index, tables_.size()); |
| uint32_t old_min_size = tables_[table_index].min_size; |
| if (count > FLAG_wasm_max_table_size - old_min_size) { |
| return std::numeric_limits<uint32_t>::max(); |
| } |
| tables_[table_index].min_size = old_min_size + count; |
| tables_[table_index].max_size = |
| std::max(old_min_size + count, tables_[table_index].max_size); |
| return old_min_size; |
| } |
| |
| uint32_t WasmModuleBuilder::AddTable(ValueType type, uint32_t min_size) { |
| tables_.push_back({type, min_size, 0, false, {}}); |
| return static_cast<uint32_t>(tables_.size() - 1); |
| } |
| |
| uint32_t WasmModuleBuilder::AddTable(ValueType type, uint32_t min_size, |
| uint32_t max_size) { |
| tables_.push_back({type, min_size, max_size, true, {}}); |
| return static_cast<uint32_t>(tables_.size() - 1); |
| } |
| |
| uint32_t WasmModuleBuilder::AddTable(ValueType type, uint32_t min_size, |
| uint32_t max_size, WasmInitExpr init) { |
| tables_.push_back({type, min_size, max_size, true, std::move(init)}); |
| return static_cast<uint32_t>(tables_.size() - 1); |
| } |
| |
| void WasmModuleBuilder::AddElementSegment(WasmElemSegment segment) { |
| element_segments_.push_back(std::move(segment)); |
| } |
| |
| void WasmModuleBuilder::SetIndirectFunction( |
| uint32_t table_index, uint32_t index_in_table, |
| uint32_t direct_function_index, |
| WasmElemSegment::FunctionIndexingMode indexing_mode) { |
| WasmElemSegment segment(zone_, kWasmFuncRef, table_index, |
| WasmInitExpr(static_cast<int>(index_in_table))); |
| segment.indexing_mode = indexing_mode; |
| segment.entries.emplace_back(WasmElemSegment::Entry::kRefFuncEntry, |
| direct_function_index); |
| AddElementSegment(std::move(segment)); |
| } |
| |
| uint32_t WasmModuleBuilder::AddImport(base::Vector<const char> name, |
| FunctionSig* sig, |
| base::Vector<const char> module) { |
| DCHECK(adding_imports_allowed_); |
| function_imports_.push_back({module, name, AddSignature(sig)}); |
| return static_cast<uint32_t>(function_imports_.size() - 1); |
| } |
| |
| uint32_t WasmModuleBuilder::AddGlobalImport(base::Vector<const char> name, |
| ValueType type, bool mutability, |
| base::Vector<const char> module) { |
| global_imports_.push_back({module, name, type.value_type_code(), mutability}); |
| return static_cast<uint32_t>(global_imports_.size() - 1); |
| } |
| |
| void WasmModuleBuilder::MarkStartFunction(WasmFunctionBuilder* function) { |
| start_function_index_ = function->func_index(); |
| } |
| |
| void WasmModuleBuilder::AddExport(base::Vector<const char> name, |
| ImportExportKindCode kind, uint32_t index) { |
| DCHECK_LE(index, std::numeric_limits<int>::max()); |
| exports_.push_back({name, kind, static_cast<int>(index)}); |
| } |
| |
| uint32_t WasmModuleBuilder::AddExportedGlobal(ValueType type, bool mutability, |
| WasmInitExpr init, |
| base::Vector<const char> name) { |
| uint32_t index = AddGlobal(type, mutability, std::move(init)); |
| AddExport(name, kExternalGlobal, index); |
| return index; |
| } |
| |
| void WasmModuleBuilder::ExportImportedFunction(base::Vector<const char> name, |
| int import_index) { |
| #if DEBUG |
| // The size of function_imports_ must not change any more. |
| adding_imports_allowed_ = false; |
| #endif |
| exports_.push_back( |
| {name, kExternalFunction, |
| import_index - static_cast<int>(function_imports_.size())}); |
| } |
| |
| uint32_t WasmModuleBuilder::AddGlobal(ValueType type, bool mutability, |
| WasmInitExpr init) { |
| globals_.push_back({type, mutability, std::move(init)}); |
| return static_cast<uint32_t>(globals_.size() - 1); |
| } |
| |
| void WasmModuleBuilder::SetMinMemorySize(uint32_t value) { |
| min_memory_size_ = value; |
| } |
| |
| void WasmModuleBuilder::SetMaxMemorySize(uint32_t value) { |
| has_max_memory_size_ = true; |
| max_memory_size_ = value; |
| } |
| |
| void WasmModuleBuilder::SetHasSharedMemory() { has_shared_memory_ = true; } |
| |
| namespace { |
| void WriteInitializerExpressionWithEnd(ZoneBuffer* buffer, |
| const WasmInitExpr& init, |
| ValueType type) { |
| switch (init.kind()) { |
| case WasmInitExpr::kI32Const: |
| buffer->write_u8(kExprI32Const); |
| buffer->write_i32v(init.immediate().i32_const); |
| break; |
| case WasmInitExpr::kI64Const: |
| buffer->write_u8(kExprI64Const); |
| buffer->write_i64v(init.immediate().i64_const); |
| break; |
| case WasmInitExpr::kF32Const: |
| buffer->write_u8(kExprF32Const); |
| buffer->write_f32(init.immediate().f32_const); |
| break; |
| case WasmInitExpr::kF64Const: |
| buffer->write_u8(kExprF64Const); |
| buffer->write_f64(init.immediate().f64_const); |
| break; |
| case WasmInitExpr::kS128Const: |
| buffer->write_u8(kSimdPrefix); |
| buffer->write_u8(kExprS128Const & 0xFF); |
| buffer->write(init.immediate().s128_const.data(), kSimd128Size); |
| break; |
| case WasmInitExpr::kGlobalGet: |
| buffer->write_u8(kExprGlobalGet); |
| buffer->write_u32v(init.immediate().index); |
| break; |
| case WasmInitExpr::kRefNullConst: |
| buffer->write_u8(kExprRefNull); |
| buffer->write_i32v(HeapType(init.immediate().heap_type).code()); |
| break; |
| case WasmInitExpr::kRefFuncConst: |
| buffer->write_u8(kExprRefFunc); |
| buffer->write_u32v(init.immediate().index); |
| break; |
| case WasmInitExpr::kNone: { |
| // No initializer, emit a default value. |
| switch (type.kind()) { |
| case kI32: |
| buffer->write_u8(kExprI32Const); |
| // LEB encoding of 0. |
| buffer->write_u8(0); |
| break; |
| case kI64: |
| buffer->write_u8(kExprI64Const); |
| // LEB encoding of 0. |
| buffer->write_u8(0); |
| break; |
| case kF32: |
| buffer->write_u8(kExprF32Const); |
| buffer->write_f32(0.f); |
| break; |
| case kF64: |
| buffer->write_u8(kExprF64Const); |
| buffer->write_f64(0.); |
| break; |
| case kOptRef: |
| buffer->write_u8(kExprRefNull); |
| buffer->write_i32v(type.heap_type().code()); |
| break; |
| case kS128: |
| buffer->write_u8(static_cast<byte>(kSimdPrefix)); |
| buffer->write_u8(static_cast<byte>(kExprS128Const & 0xff)); |
| for (int i = 0; i < kSimd128Size; i++) buffer->write_u8(0); |
| break; |
| case kI8: |
| case kI16: |
| case kVoid: |
| case kBottom: |
| case kRef: |
| case kRtt: |
| case kRttWithDepth: |
| UNREACHABLE(); |
| } |
| break; |
| } |
| case WasmInitExpr::kStructNewWithRtt: |
| STATIC_ASSERT((kExprStructNewWithRtt >> 8) == kGCPrefix); |
| for (const WasmInitExpr& operand : init.operands()) { |
| WriteInitializerExpressionWithEnd(buffer, operand, kWasmBottom); |
| } |
| buffer->write_u8(kGCPrefix); |
| buffer->write_u8(static_cast<uint8_t>(kExprStructNewWithRtt)); |
| buffer->write_u32v(init.immediate().index); |
| break; |
| case WasmInitExpr::kArrayInit: |
| STATIC_ASSERT((kExprArrayInit >> 8) == kGCPrefix); |
| for (const WasmInitExpr& operand : init.operands()) { |
| WriteInitializerExpressionWithEnd(buffer, operand, kWasmBottom); |
| } |
| buffer->write_u8(kGCPrefix); |
| buffer->write_u8(static_cast<uint8_t>(kExprArrayInit)); |
| buffer->write_u32v(init.immediate().index); |
| buffer->write_u32v(static_cast<uint32_t>(init.operands().size() - 1)); |
| break; |
| case WasmInitExpr::kRttCanon: |
| STATIC_ASSERT((kExprRttCanon >> 8) == kGCPrefix); |
| buffer->write_u8(kGCPrefix); |
| buffer->write_u8(static_cast<uint8_t>(kExprRttCanon)); |
| buffer->write_i32v(static_cast<int32_t>(init.immediate().index)); |
| break; |
| case WasmInitExpr::kRttSub: |
| case WasmInitExpr::kRttFreshSub: |
| // The operand to rtt.sub must be emitted first. |
| WriteInitializerExpressionWithEnd(buffer, init.operands()[0], |
| kWasmBottom); |
| STATIC_ASSERT((kExprRttSub >> 8) == kGCPrefix); |
| STATIC_ASSERT((kExprRttFreshSub >> 8) == kGCPrefix); |
| buffer->write_u8(kGCPrefix); |
| buffer->write_u8(static_cast<uint8_t>(init.kind() == WasmInitExpr::kRttSub |
| ? kExprRttSub |
| : kExprRttFreshSub)); |
| buffer->write_i32v(static_cast<int32_t>(init.immediate().index)); |
| break; |
| } |
| } |
| |
| void WriteInitializerExpression(ZoneBuffer* buffer, const WasmInitExpr& init, |
| ValueType type) { |
| WriteInitializerExpressionWithEnd(buffer, init, type); |
| buffer->write_u8(kExprEnd); |
| } |
| } // namespace |
| |
| void WasmModuleBuilder::WriteTo(ZoneBuffer* buffer) const { |
| // == Emit magic ============================================================= |
| buffer->write_u32(kWasmMagic); |
| buffer->write_u32(kWasmVersion); |
| |
| // == Emit types ============================================================= |
| if (types_.size() > 0) { |
| size_t start = EmitSection(kTypeSectionCode, buffer); |
| buffer->write_size(types_.size()); |
| |
| for (const Type& type : types_) { |
| switch (type.kind) { |
| case Type::kFunctionSig: { |
| FunctionSig* sig = type.sig; |
| buffer->write_u8(kWasmFunctionTypeCode); |
| buffer->write_size(sig->parameter_count()); |
| for (auto param : sig->parameters()) { |
| WriteValueType(buffer, param); |
| } |
| buffer->write_size(sig->return_count()); |
| for (auto ret : sig->returns()) { |
| WriteValueType(buffer, ret); |
| } |
| break; |
| } |
| case Type::kStructType: { |
| StructType* struct_type = type.struct_type; |
| buffer->write_u8(kWasmStructTypeCode); |
| buffer->write_size(struct_type->field_count()); |
| for (uint32_t i = 0; i < struct_type->field_count(); i++) { |
| WriteValueType(buffer, struct_type->field(i)); |
| buffer->write_u8(struct_type->mutability(i) ? 1 : 0); |
| } |
| break; |
| } |
| case Type::kArrayType: { |
| ArrayType* array_type = type.array_type; |
| buffer->write_u8(kWasmArrayTypeCode); |
| WriteValueType(buffer, array_type->element_type()); |
| buffer->write_u8(array_type->mutability() ? 1 : 0); |
| break; |
| } |
| } |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == Emit imports =========================================================== |
| if (global_imports_.size() + function_imports_.size() > 0) { |
| size_t start = EmitSection(kImportSectionCode, buffer); |
| buffer->write_size(global_imports_.size() + function_imports_.size()); |
| for (auto import : global_imports_) { |
| buffer->write_string(import.module); // module name |
| buffer->write_string(import.name); // field name |
| buffer->write_u8(kExternalGlobal); |
| buffer->write_u8(import.type_code); |
| buffer->write_u8(import.mutability ? 1 : 0); |
| } |
| for (auto import : function_imports_) { |
| buffer->write_string(import.module); // module name |
| buffer->write_string(import.name); // field name |
| buffer->write_u8(kExternalFunction); |
| buffer->write_u32v(import.sig_index); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == Emit function signatures =============================================== |
| uint32_t num_function_names = 0; |
| if (functions_.size() > 0) { |
| size_t start = EmitSection(kFunctionSectionCode, buffer); |
| buffer->write_size(functions_.size()); |
| for (auto* function : functions_) { |
| function->WriteSignature(buffer); |
| if (!function->name_.empty()) ++num_function_names; |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == Emit tables ============================================================ |
| if (tables_.size() > 0) { |
| size_t start = EmitSection(kTableSectionCode, buffer); |
| buffer->write_size(tables_.size()); |
| for (const WasmTable& table : tables_) { |
| WriteValueType(buffer, table.type); |
| buffer->write_u8(table.has_maximum ? kWithMaximum : kNoMaximum); |
| buffer->write_size(table.min_size); |
| if (table.has_maximum) buffer->write_size(table.max_size); |
| if (table.init.kind() != WasmInitExpr::kNone) { |
| WriteInitializerExpression(buffer, table.init, table.type); |
| } |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == Emit memory declaration ================================================ |
| { |
| size_t start = EmitSection(kMemorySectionCode, buffer); |
| buffer->write_u8(1); // memory count |
| if (has_shared_memory_) { |
| buffer->write_u8(has_max_memory_size_ ? kSharedWithMaximum |
| : kSharedNoMaximum); |
| } else { |
| buffer->write_u8(has_max_memory_size_ ? kWithMaximum : kNoMaximum); |
| } |
| buffer->write_u32v(min_memory_size_); |
| if (has_max_memory_size_) { |
| buffer->write_u32v(max_memory_size_); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // Emit event section. |
| if (exceptions_.size() > 0) { |
| size_t start = EmitSection(kTagSectionCode, buffer); |
| buffer->write_size(exceptions_.size()); |
| for (int type : exceptions_) { |
| buffer->write_u32v(kExceptionAttribute); |
| buffer->write_u32v(type); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == Emit globals =========================================================== |
| if (globals_.size() > 0) { |
| size_t start = EmitSection(kGlobalSectionCode, buffer); |
| buffer->write_size(globals_.size()); |
| |
| for (const WasmGlobal& global : globals_) { |
| WriteValueType(buffer, global.type); |
| buffer->write_u8(global.mutability ? 1 : 0); |
| WriteInitializerExpression(buffer, global.init, global.type); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == emit exports =========================================================== |
| if (exports_.size() > 0) { |
| size_t start = EmitSection(kExportSectionCode, buffer); |
| buffer->write_size(exports_.size()); |
| for (auto ex : exports_) { |
| buffer->write_string(ex.name); |
| buffer->write_u8(ex.kind); |
| switch (ex.kind) { |
| case kExternalFunction: |
| buffer->write_size(ex.index + function_imports_.size()); |
| break; |
| case kExternalGlobal: |
| buffer->write_size(ex.index + global_imports_.size()); |
| break; |
| case kExternalMemory: |
| case kExternalTable: |
| // The WasmModuleBuilder doesn't support importing tables or memories |
| // yet, so there is no index offset to add. |
| buffer->write_size(ex.index); |
| break; |
| case kExternalTag: |
| UNREACHABLE(); |
| } |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == emit start function index ============================================== |
| if (start_function_index_ >= 0) { |
| size_t start = EmitSection(kStartSectionCode, buffer); |
| buffer->write_size(start_function_index_ + function_imports_.size()); |
| FixupSection(buffer, start); |
| } |
| |
| // == emit element segments ================================================== |
| if (element_segments_.size() > 0) { |
| size_t start = EmitSection(kElementSectionCode, buffer); |
| buffer->write_size(element_segments_.size()); |
| for (const WasmElemSegment& segment : element_segments_) { |
| bool is_active = segment.status == WasmElemSegment::kStatusActive; |
| // If this segment is expressible in the backwards-compatible syntax |
| // (before reftypes proposal), we should emit it in that syntax. |
| // This is the case if the segment is active and all entries are function |
| // references. Note that this is currently the only path that allows |
| // kRelativeToImports function indexing mode. |
| // TODO(manoskouk): Remove this logic once reftypes has shipped. |
| bool backwards_compatible = |
| is_active && segment.table_index == 0 && |
| std::all_of( |
| segment.entries.begin(), segment.entries.end(), [](auto& entry) { |
| return entry.kind == |
| WasmModuleBuilder::WasmElemSegment::Entry::kRefFuncEntry; |
| }); |
| if (backwards_compatible) { |
| buffer->write_u8(0); |
| WriteInitializerExpression(buffer, segment.offset, segment.type); |
| buffer->write_size(segment.entries.size()); |
| for (const WasmElemSegment::Entry entry : segment.entries) { |
| buffer->write_u32v( |
| segment.indexing_mode == WasmElemSegment::kRelativeToImports |
| ? entry.index |
| : entry.index + |
| static_cast<uint32_t>(function_imports_.size())); |
| } |
| } else { |
| DCHECK_EQ(segment.indexing_mode, WasmElemSegment::kRelativeToImports); |
| // If we pick the general syntax, we always explicitly emit the table |
| // index and the type, and use the expressions-as-elements syntax. I.e. |
| // the initial byte is one of 0x05, 0x06, and 0x07. |
| uint8_t kind_mask = |
| segment.status == WasmElemSegment::kStatusActive |
| ? 0b10 |
| : segment.status == WasmElemSegment::kStatusDeclarative ? 0b11 |
| : 0b01; |
| uint8_t expressions_as_elements_mask = 0b100; |
| buffer->write_u8(kind_mask | expressions_as_elements_mask); |
| if (is_active) { |
| buffer->write_u32v(segment.table_index); |
| WriteInitializerExpression(buffer, segment.offset, segment.type); |
| } |
| WriteValueType(buffer, segment.type); |
| buffer->write_size(segment.entries.size()); |
| for (const WasmElemSegment::Entry entry : segment.entries) { |
| uint8_t opcode = |
| entry.kind == WasmElemSegment::Entry::kGlobalGetEntry |
| ? kExprGlobalGet |
| : entry.kind == WasmElemSegment::Entry::kRefFuncEntry |
| ? kExprRefFunc |
| : kExprRefNull; |
| buffer->write_u8(opcode); |
| buffer->write_u32v(entry.index); |
| buffer->write_u8(kExprEnd); |
| } |
| } |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == emit compilation hints section ========================================= |
| bool emit_compilation_hints = false; |
| for (auto* fn : functions_) { |
| if (fn->hint_ != kNoCompilationHint) { |
| emit_compilation_hints = true; |
| break; |
| } |
| } |
| if (emit_compilation_hints) { |
| // Emit the section code. |
| buffer->write_u8(kUnknownSectionCode); |
| // Emit a placeholder for section length. |
| size_t start = buffer->reserve_u32v(); |
| // Emit custom section name. |
| buffer->write_string(base::CStrVector("compilationHints")); |
| // Emit hint count. |
| buffer->write_size(functions_.size()); |
| // Emit hint bytes. |
| for (auto* fn : functions_) { |
| uint8_t hint_byte = |
| fn->hint_ != kNoCompilationHint ? fn->hint_ : kDefaultCompilationHint; |
| buffer->write_u8(hint_byte); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == emit code ============================================================== |
| if (functions_.size() > 0) { |
| size_t start = EmitSection(kCodeSectionCode, buffer); |
| buffer->write_size(functions_.size()); |
| for (auto* function : functions_) { |
| function->WriteBody(buffer); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == emit data segments ===================================================== |
| if (data_segments_.size() > 0) { |
| size_t start = EmitSection(kDataSectionCode, buffer); |
| buffer->write_size(data_segments_.size()); |
| |
| for (auto segment : data_segments_) { |
| buffer->write_u8(0); // linear memory segment |
| buffer->write_u8(kExprI32Const); // initializer expression for dest |
| buffer->write_u32v(segment.dest); |
| buffer->write_u8(kExprEnd); |
| buffer->write_u32v(static_cast<uint32_t>(segment.data.size())); |
| buffer->write(&segment.data[0], segment.data.size()); |
| } |
| FixupSection(buffer, start); |
| } |
| |
| // == Emit names ============================================================= |
| if (num_function_names > 0 || !function_imports_.empty()) { |
| // Emit the section code. |
| buffer->write_u8(kUnknownSectionCode); |
| // Emit a placeholder for the length. |
| size_t start = buffer->reserve_u32v(); |
| // Emit the section string. |
| buffer->write_string(base::CStrVector("name")); |
| // Emit a subsection for the function names. |
| buffer->write_u8(NameSectionKindCode::kFunction); |
| // Emit a placeholder for the subsection length. |
| size_t functions_start = buffer->reserve_u32v(); |
| // Emit the function names. |
| // Imports are always named. |
| uint32_t num_imports = static_cast<uint32_t>(function_imports_.size()); |
| buffer->write_size(num_imports + num_function_names); |
| uint32_t function_index = 0; |
| for (; function_index < num_imports; ++function_index) { |
| const WasmFunctionImport* import = &function_imports_[function_index]; |
| DCHECK(!import->name.empty()); |
| buffer->write_u32v(function_index); |
| buffer->write_string(import->name); |
| } |
| if (num_function_names > 0) { |
| for (auto* function : functions_) { |
| DCHECK_EQ(function_index, |
| function->func_index() + function_imports_.size()); |
| if (!function->name_.empty()) { |
| buffer->write_u32v(function_index); |
| buffer->write_string(function->name_); |
| } |
| ++function_index; |
| } |
| } |
| FixupSection(buffer, functions_start); |
| FixupSection(buffer, start); |
| } |
| } |
| |
| void WasmModuleBuilder::WriteAsmJsOffsetTable(ZoneBuffer* buffer) const { |
| // == Emit asm.js offset table =============================================== |
| buffer->write_size(functions_.size()); |
| // Emit the offset table per function. |
| for (auto* function : functions_) { |
| function->WriteAsmWasmOffsetTable(buffer); |
| } |
| } |
| } // namespace wasm |
| } // namespace internal |
| } // namespace v8 |
