| // 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/module-decoder.h" |
| |
| #include "src/base/functional.h" |
| #include "src/base/platform/platform.h" |
| #include "src/macro-assembler.h" |
| #include "src/objects.h" |
| #include "src/v8.h" |
| |
| #include "src/wasm/decoder.h" |
| |
| namespace v8 { |
| namespace internal { |
| namespace wasm { |
| |
| #if DEBUG |
| #define TRACE(...) \ |
| do { \ |
| if (FLAG_trace_wasm_decoder) PrintF(__VA_ARGS__); \ |
| } while (false) |
| #else |
| #define TRACE(...) |
| #endif |
| |
| // The main logic for decoding the bytes of a module. |
| class ModuleDecoder : public Decoder { |
| public: |
| ModuleDecoder(Zone* zone, const byte* module_start, const byte* module_end, |
| ModuleOrigin origin) |
| : Decoder(module_start, module_end), module_zone(zone), origin_(origin) { |
| result_.start = start_; |
| if (limit_ < start_) { |
| error(start_, "end is less than start"); |
| limit_ = start_; |
| } |
| } |
| |
| virtual void onFirstError() { |
| pc_ = limit_; // On error, terminate section decoding loop. |
| } |
| |
| static void DumpModule(WasmModule* module, ModuleResult result) { |
| std::string path; |
| if (FLAG_dump_wasm_module_path) { |
| path = FLAG_dump_wasm_module_path; |
| if (path.size() && |
| !base::OS::isDirectorySeparator(path[path.size() - 1])) { |
| path += base::OS::DirectorySeparator(); |
| } |
| } |
| // File are named `HASH.{ok,failed}.wasm`. |
| size_t hash = base::hash_range(module->module_start, module->module_end); |
| char buf[32] = {'\0'}; |
| #if V8_OS_WIN && _MSC_VER < 1900 |
| #define snprintf sprintf_s |
| #endif |
| snprintf(buf, sizeof(buf) - 1, "%016zx.%s.wasm", hash, |
| result.ok() ? "ok" : "failed"); |
| std::string name(buf); |
| if (FILE* wasm_file = base::OS::FOpen((path + name).c_str(), "wb")) { |
| fwrite(module->module_start, module->module_end - module->module_start, 1, |
| wasm_file); |
| fclose(wasm_file); |
| } |
| } |
| |
| // Decodes an entire module. |
| ModuleResult DecodeModule(WasmModule* module, bool verify_functions = true) { |
| pc_ = start_; |
| module->module_start = start_; |
| module->module_end = limit_; |
| module->min_mem_pages = 0; |
| module->max_mem_pages = 0; |
| module->mem_export = false; |
| module->mem_external = false; |
| module->origin = origin_; |
| |
| const byte* pos = pc_; |
| int current_order = 0; |
| uint32_t magic_word = consume_u32("wasm magic"); |
| #define BYTES(x) (x & 0xff), (x >> 8) & 0xff, (x >> 16) & 0xff, (x >> 24) & 0xff |
| if (magic_word != kWasmMagic) { |
| error(pos, pos, |
| "expected magic word %02x %02x %02x %02x, " |
| "found %02x %02x %02x %02x", |
| BYTES(kWasmMagic), BYTES(magic_word)); |
| goto done; |
| } |
| |
| pos = pc_; |
| { |
| uint32_t magic_version = consume_u32("wasm version"); |
| if (magic_version != kWasmVersion) { |
| error(pos, pos, |
| "expected version %02x %02x %02x %02x, " |
| "found %02x %02x %02x %02x", |
| BYTES(kWasmVersion), BYTES(magic_version)); |
| goto done; |
| } |
| } |
| |
| // Decode the module sections. |
| while (pc_ < limit_) { |
| TRACE("DecodeSection\n"); |
| pos = pc_; |
| |
| // Read the section name. |
| int string_leb_length = 0; |
| uint32_t string_length = |
| consume_u32v(&string_leb_length, "section name length"); |
| const byte* section_name_start = pc_; |
| consume_bytes(string_length); |
| if (failed()) { |
| TRACE("Section name of length %u couldn't be read\n", string_length); |
| break; |
| } |
| |
| WasmSection::Code section = |
| WasmSection::lookup(section_name_start, string_length); |
| |
| // Read and check the section size. |
| int section_leb_length = 0; |
| uint32_t section_length = |
| consume_u32v(§ion_leb_length, "section length"); |
| if (!checkAvailable(section_length)) { |
| // The section would extend beyond the end of the module. |
| break; |
| } |
| const byte* section_start = pc_; |
| const byte* expected_section_end = pc_ + section_length; |
| |
| current_order = CheckSectionOrder(current_order, section); |
| |
| switch (section) { |
| case WasmSection::Code::End: |
| // Terminate section decoding. |
| limit_ = pc_; |
| break; |
| case WasmSection::Code::Memory: { |
| int length; |
| module->min_mem_pages = consume_u32v(&length, "min memory"); |
| module->max_mem_pages = consume_u32v(&length, "max memory"); |
| module->mem_export = consume_u8("export memory") != 0; |
| break; |
| } |
| case WasmSection::Code::Signatures: { |
| int length; |
| uint32_t signatures_count = consume_u32v(&length, "signatures count"); |
| module->signatures.reserve(SafeReserve(signatures_count)); |
| // Decode signatures. |
| for (uint32_t i = 0; i < signatures_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeSignature[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| FunctionSig* s = consume_sig(); |
| module->signatures.push_back(s); |
| } |
| break; |
| } |
| case WasmSection::Code::FunctionSignatures: { |
| int length; |
| uint32_t functions_count = consume_u32v(&length, "functions count"); |
| module->functions.reserve(SafeReserve(functions_count)); |
| for (uint32_t i = 0; i < functions_count; i++) { |
| module->functions.push_back({nullptr, // sig |
| i, // func_index |
| 0, // sig_index |
| 0, // name_offset |
| 0, // name_length |
| 0, // code_start_offset |
| 0, // code_end_offset |
| false}); // exported |
| WasmFunction* function = &module->functions.back(); |
| function->sig_index = consume_sig_index(module, &function->sig); |
| } |
| break; |
| } |
| case WasmSection::Code::FunctionBodies: { |
| int length; |
| const byte* pos = pc_; |
| uint32_t functions_count = consume_u32v(&length, "functions count"); |
| if (functions_count != module->functions.size()) { |
| error(pos, pos, "function body count %u mismatch (%u expected)", |
| functions_count, |
| static_cast<uint32_t>(module->functions.size())); |
| break; |
| } |
| for (uint32_t i = 0; i < functions_count; i++) { |
| WasmFunction* function = &module->functions[i]; |
| int length; |
| uint32_t size = consume_u32v(&length, "body size"); |
| function->code_start_offset = pc_offset(); |
| function->code_end_offset = pc_offset() + size; |
| |
| TRACE(" +%d %-20s: (%d bytes)\n", pc_offset(), "function body", |
| size); |
| pc_ += size; |
| if (pc_ > limit_) { |
| error(pc_, "function body extends beyond end of file"); |
| } |
| } |
| break; |
| } |
| case WasmSection::Code::OldFunctions: { |
| int length; |
| uint32_t functions_count = consume_u32v(&length, "functions count"); |
| module->functions.reserve(SafeReserve(functions_count)); |
| // Set up module environment for verification. |
| ModuleEnv menv; |
| menv.module = module; |
| menv.instance = nullptr; |
| menv.origin = origin_; |
| // Decode functions. |
| for (uint32_t i = 0; i < functions_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeFunction[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| |
| module->functions.push_back({nullptr, // sig |
| i, // func_index |
| 0, // sig_index |
| 0, // name_offset |
| 0, // name_length |
| 0, // code_start_offset |
| 0, // code_end_offset |
| false}); // exported |
| WasmFunction* function = &module->functions.back(); |
| DecodeFunctionInModule(module, function, false); |
| } |
| if (ok() && verify_functions) { |
| for (uint32_t i = 0; i < functions_count; i++) { |
| if (failed()) break; |
| WasmFunction* function = &module->functions[i]; |
| VerifyFunctionBody(i, &menv, function); |
| if (result_.failed()) { |
| error(result_.error_pc, result_.error_msg.get()); |
| } |
| } |
| } |
| break; |
| } |
| case WasmSection::Code::Names: { |
| int length; |
| const byte* pos = pc_; |
| uint32_t functions_count = consume_u32v(&length, "functions count"); |
| if (functions_count != module->functions.size()) { |
| error(pos, pos, "function name count %u mismatch (%u expected)", |
| functions_count, |
| static_cast<uint32_t>(module->functions.size())); |
| break; |
| } |
| |
| for (uint32_t i = 0; i < functions_count; i++) { |
| WasmFunction* function = &module->functions[i]; |
| function->name_offset = |
| consume_string(&function->name_length, false); |
| |
| uint32_t local_names_count = |
| consume_u32v(&length, "local names count"); |
| for (uint32_t j = 0; j < local_names_count; j++) { |
| uint32_t unused = 0; |
| uint32_t offset = consume_string(&unused, false); |
| USE(unused); |
| USE(offset); |
| } |
| } |
| break; |
| } |
| case WasmSection::Code::Globals: { |
| int length; |
| uint32_t globals_count = consume_u32v(&length, "globals count"); |
| module->globals.reserve(SafeReserve(globals_count)); |
| // Decode globals. |
| for (uint32_t i = 0; i < globals_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeGlobal[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| module->globals.push_back({0, 0, MachineType::Int32(), 0, false}); |
| WasmGlobal* global = &module->globals.back(); |
| DecodeGlobalInModule(global); |
| } |
| break; |
| } |
| case WasmSection::Code::DataSegments: { |
| int length; |
| uint32_t data_segments_count = |
| consume_u32v(&length, "data segments count"); |
| module->data_segments.reserve(SafeReserve(data_segments_count)); |
| // Decode data segments. |
| for (uint32_t i = 0; i < data_segments_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeDataSegment[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| module->data_segments.push_back({0, // dest_addr |
| 0, // source_offset |
| 0, // source_size |
| false}); // init |
| WasmDataSegment* segment = &module->data_segments.back(); |
| DecodeDataSegmentInModule(module, segment); |
| } |
| break; |
| } |
| case WasmSection::Code::FunctionTable: { |
| // An indirect function table requires functions first. |
| CheckForFunctions(module, section); |
| int length; |
| uint32_t function_table_count = |
| consume_u32v(&length, "function table count"); |
| module->function_table.reserve(SafeReserve(function_table_count)); |
| // Decode function table. |
| for (uint32_t i = 0; i < function_table_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeFunctionTable[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| uint16_t index = consume_u32v(&length); |
| if (index >= module->functions.size()) { |
| error(pc_ - 2, "invalid function index"); |
| break; |
| } |
| module->function_table.push_back(index); |
| } |
| break; |
| } |
| case WasmSection::Code::StartFunction: { |
| // Declares a start function for a module. |
| CheckForFunctions(module, section); |
| if (module->start_function_index >= 0) { |
| error("start function already declared"); |
| break; |
| } |
| WasmFunction* func; |
| const byte* pos = pc_; |
| module->start_function_index = consume_func_index(module, &func); |
| if (func && func->sig->parameter_count() > 0) { |
| error(pos, "invalid start function: non-zero parameter count"); |
| break; |
| } |
| break; |
| } |
| case WasmSection::Code::ImportTable: { |
| int length; |
| uint32_t import_table_count = |
| consume_u32v(&length, "import table count"); |
| module->import_table.reserve(SafeReserve(import_table_count)); |
| // Decode import table. |
| for (uint32_t i = 0; i < import_table_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeImportTable[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| |
| module->import_table.push_back({nullptr, // sig |
| 0, // sig_index |
| 0, // module_name_offset |
| 0, // module_name_length |
| 0, // function_name_offset |
| 0}); // function_name_length |
| WasmImport* import = &module->import_table.back(); |
| |
| import->sig_index = consume_sig_index(module, &import->sig); |
| const byte* pos = pc_; |
| import->module_name_offset = |
| consume_string(&import->module_name_length, true); |
| if (import->module_name_length == 0) { |
| error(pos, "import module name cannot be NULL"); |
| } |
| import->function_name_offset = |
| consume_string(&import->function_name_length, true); |
| } |
| break; |
| } |
| case WasmSection::Code::ExportTable: { |
| // Declares an export table. |
| CheckForFunctions(module, section); |
| int length; |
| uint32_t export_table_count = |
| consume_u32v(&length, "export table count"); |
| module->export_table.reserve(SafeReserve(export_table_count)); |
| // Decode export table. |
| for (uint32_t i = 0; i < export_table_count; i++) { |
| if (failed()) break; |
| TRACE("DecodeExportTable[%d] module+%d\n", i, |
| static_cast<int>(pc_ - start_)); |
| |
| module->export_table.push_back({0, // func_index |
| 0, // name_offset |
| 0}); // name_length |
| WasmExport* exp = &module->export_table.back(); |
| |
| WasmFunction* func; |
| exp->func_index = consume_func_index(module, &func); |
| exp->name_offset = consume_string(&exp->name_length, true); |
| } |
| break; |
| } |
| case WasmSection::Code::Max: |
| // Skip unknown sections. |
| TRACE("Unknown section: '"); |
| for (uint32_t i = 0; i != string_length; ++i) { |
| TRACE("%c", *(section_name_start + i)); |
| } |
| TRACE("'\n"); |
| consume_bytes(section_length); |
| break; |
| } |
| |
| if (pc_ != expected_section_end) { |
| const char* diff = pc_ < expected_section_end ? "shorter" : "longer"; |
| size_t expected_length = static_cast<size_t>(section_length); |
| size_t actual_length = static_cast<size_t>(pc_ - section_start); |
| error(pc_, pc_, |
| "section \"%s\" %s (%zu bytes) than specified (%zu bytes)", |
| WasmSection::getName(section), diff, actual_length, |
| expected_length); |
| break; |
| } |
| } |
| |
| done: |
| ModuleResult result = toResult(module); |
| if (FLAG_dump_wasm_module) { |
| DumpModule(module, result); |
| } |
| return result; |
| } |
| |
| uint32_t SafeReserve(uint32_t count) { |
| // Avoid OOM by only reserving up to a certain size. |
| const uint32_t kMaxReserve = 20000; |
| return count < kMaxReserve ? count : kMaxReserve; |
| } |
| |
| void CheckForFunctions(WasmModule* module, WasmSection::Code section) { |
| if (module->functions.size() == 0) { |
| error(pc_ - 1, nullptr, "functions must appear before section %s", |
| WasmSection::getName(section)); |
| } |
| } |
| |
| int CheckSectionOrder(int current_order, WasmSection::Code section) { |
| int next_order = WasmSection::getOrder(section); |
| if (next_order == 0) return current_order; |
| if (next_order == current_order) { |
| error(pc_, pc_, "section \"%s\" already defined", |
| WasmSection::getName(section)); |
| } |
| if (next_order < current_order) { |
| error(pc_, pc_, "section \"%s\" out of order", |
| WasmSection::getName(section)); |
| } |
| return next_order; |
| } |
| |
| // Decodes a single anonymous function starting at {start_}. |
| FunctionResult DecodeSingleFunction(ModuleEnv* module_env, |
| WasmFunction* function) { |
| pc_ = start_; |
| function->sig = consume_sig(); // read signature |
| function->name_offset = 0; // ---- name |
| function->name_length = 0; // ---- name length |
| function->code_start_offset = off(pc_); // ---- code start |
| function->code_end_offset = off(limit_); // ---- code end |
| function->exported = false; // ---- exported |
| |
| if (ok()) VerifyFunctionBody(0, module_env, function); |
| |
| FunctionResult result; |
| result.CopyFrom(result_); // Copy error code and location. |
| result.val = function; |
| return result; |
| } |
| |
| // Decodes a single function signature at {start}. |
| FunctionSig* DecodeFunctionSignature(const byte* start) { |
| pc_ = start; |
| FunctionSig* result = consume_sig(); |
| return ok() ? result : nullptr; |
| } |
| |
| private: |
| Zone* module_zone; |
| ModuleResult result_; |
| ModuleOrigin origin_; |
| |
| uint32_t off(const byte* ptr) { return static_cast<uint32_t>(ptr - start_); } |
| |
| // Decodes a single global entry inside a module starting at {pc_}. |
| void DecodeGlobalInModule(WasmGlobal* global) { |
| global->name_offset = consume_string(&global->name_length, false); |
| DCHECK(unibrow::Utf8::Validate(start_ + global->name_offset, |
| global->name_length)); |
| global->type = mem_type(); |
| global->offset = 0; |
| global->exported = consume_u8("exported") != 0; |
| } |
| |
| // Decodes a single function entry inside a module starting at {pc_}. |
| // TODO(titzer): legacy function body; remove |
| void DecodeFunctionInModule(WasmModule* module, WasmFunction* function, |
| bool verify_body = true) { |
| byte decl_bits = consume_u8("function decl"); |
| |
| const byte* sigpos = pc_; |
| function->sig_index = consume_u16("signature index"); |
| |
| if (function->sig_index >= module->signatures.size()) { |
| return error(sigpos, "invalid signature index"); |
| } else { |
| function->sig = module->signatures[function->sig_index]; |
| } |
| |
| TRACE(" +%d <function attributes:%s%s>\n", static_cast<int>(pc_ - start_), |
| decl_bits & kDeclFunctionName ? " name" : "", |
| decl_bits & kDeclFunctionExport ? " exported" : ""); |
| |
| function->exported = decl_bits & kDeclFunctionExport; |
| |
| if (decl_bits & kDeclFunctionName) { |
| function->name_offset = |
| consume_string(&function->name_length, function->exported); |
| } |
| |
| uint16_t size = consume_u16("body size"); |
| if (ok()) { |
| if ((pc_ + size) > limit_) { |
| return error(pc_, limit_, |
| "expected %d bytes for function body, fell off end", size); |
| } |
| function->code_start_offset = static_cast<uint32_t>(pc_ - start_); |
| function->code_end_offset = function->code_start_offset + size; |
| TRACE(" +%d %-20s: (%d bytes)\n", static_cast<int>(pc_ - start_), |
| "function body", size); |
| pc_ += size; |
| } |
| } |
| |
| bool IsWithinLimit(uint32_t limit, uint32_t offset, uint32_t size) { |
| if (offset > limit) return false; |
| if ((offset + size) < offset) return false; // overflow |
| return (offset + size) <= limit; |
| } |
| |
| // Decodes a single data segment entry inside a module starting at {pc_}. |
| void DecodeDataSegmentInModule(WasmModule* module, WasmDataSegment* segment) { |
| const byte* start = pc_; |
| int length; |
| segment->dest_addr = consume_u32v(&length, "destination"); |
| segment->source_size = consume_u32v(&length, "source size"); |
| segment->source_offset = static_cast<uint32_t>(pc_ - start_); |
| segment->init = true; |
| |
| // Validate the data is in the module. |
| uint32_t module_limit = static_cast<uint32_t>(limit_ - start_); |
| if (!IsWithinLimit(module_limit, segment->source_offset, |
| segment->source_size)) { |
| error(start, "segment out of bounds of module"); |
| } |
| |
| // Validate that the segment will fit into the (minimum) memory. |
| uint32_t memory_limit = |
| WasmModule::kPageSize * (module ? module->min_mem_pages |
| : WasmModule::kMaxMemPages); |
| if (!IsWithinLimit(memory_limit, segment->dest_addr, |
| segment->source_size)) { |
| error(start, "segment out of bounds of memory"); |
| } |
| |
| consume_bytes(segment->source_size); |
| } |
| |
| // Verifies the body (code) of a given function. |
| void VerifyFunctionBody(uint32_t func_num, ModuleEnv* menv, |
| WasmFunction* function) { |
| if (FLAG_trace_wasm_decoder || FLAG_trace_wasm_decode_time) { |
| OFStream os(stdout); |
| os << "Verifying WASM function " << WasmFunctionName(function, menv) |
| << std::endl; |
| } |
| FunctionBody body = {menv, function->sig, start_, |
| start_ + function->code_start_offset, |
| start_ + function->code_end_offset}; |
| TreeResult result = VerifyWasmCode(module_zone->allocator(), body); |
| if (result.failed()) { |
| // Wrap the error message from the function decoder. |
| std::ostringstream str; |
| str << "in function " << WasmFunctionName(function, menv) << ": "; |
| str << result; |
| std::string strval = str.str(); |
| const char* raw = strval.c_str(); |
| size_t len = strlen(raw); |
| char* buffer = new char[len]; |
| strncpy(buffer, raw, len); |
| buffer[len - 1] = 0; |
| |
| // Copy error code and location. |
| result_.CopyFrom(result); |
| result_.error_msg.Reset(buffer); |
| } |
| } |
| |
| // Reads a single 32-bit unsigned integer interpreted as an offset, checking |
| // the offset is within bounds and advances. |
| uint32_t consume_offset(const char* name = nullptr) { |
| uint32_t offset = consume_u32(name ? name : "offset"); |
| if (offset > static_cast<uint32_t>(limit_ - start_)) { |
| error(pc_ - sizeof(uint32_t), "offset out of bounds of module"); |
| } |
| return offset; |
| } |
| |
| // Reads a length-prefixed string, checking that it is within bounds. Returns |
| // the offset of the string, and the length as an out parameter. |
| uint32_t consume_string(uint32_t* length, bool validate_utf8) { |
| int varint_length; |
| *length = consume_u32v(&varint_length, "string length"); |
| uint32_t offset = pc_offset(); |
| TRACE(" +%u %-20s: (%u bytes)\n", offset, "string", *length); |
| if (validate_utf8 && !unibrow::Utf8::Validate(pc_, *length)) { |
| error(pc_, "no valid UTF-8 string"); |
| } |
| consume_bytes(*length); |
| return offset; |
| } |
| |
| uint32_t consume_sig_index(WasmModule* module, FunctionSig** sig) { |
| const byte* pos = pc_; |
| int length; |
| uint32_t sig_index = consume_u32v(&length, "signature index"); |
| if (sig_index >= module->signatures.size()) { |
| error(pos, pos, "signature index %u out of bounds (%d signatures)", |
| sig_index, static_cast<int>(module->signatures.size())); |
| *sig = nullptr; |
| return 0; |
| } |
| *sig = module->signatures[sig_index]; |
| return sig_index; |
| } |
| |
| uint32_t consume_func_index(WasmModule* module, WasmFunction** func) { |
| const byte* pos = pc_; |
| int length; |
| uint32_t func_index = consume_u32v(&length, "function index"); |
| if (func_index >= module->functions.size()) { |
| error(pos, pos, "function index %u out of bounds (%d functions)", |
| func_index, static_cast<int>(module->functions.size())); |
| *func = nullptr; |
| return 0; |
| } |
| *func = &module->functions[func_index]; |
| return func_index; |
| } |
| |
| // Reads a single 8-bit integer, interpreting it as a local type. |
| LocalType consume_local_type() { |
| byte val = consume_u8("local type"); |
| LocalTypeCode t = static_cast<LocalTypeCode>(val); |
| switch (t) { |
| case kLocalVoid: |
| return kAstStmt; |
| case kLocalI32: |
| return kAstI32; |
| case kLocalI64: |
| return kAstI64; |
| case kLocalF32: |
| return kAstF32; |
| case kLocalF64: |
| return kAstF64; |
| default: |
| error(pc_ - 1, "invalid local type"); |
| return kAstStmt; |
| } |
| } |
| |
| // Reads a single 8-bit integer, interpreting it as a memory type. |
| MachineType mem_type() { |
| byte val = consume_u8("memory type"); |
| MemTypeCode t = static_cast<MemTypeCode>(val); |
| switch (t) { |
| case kMemI8: |
| return MachineType::Int8(); |
| case kMemU8: |
| return MachineType::Uint8(); |
| case kMemI16: |
| return MachineType::Int16(); |
| case kMemU16: |
| return MachineType::Uint16(); |
| case kMemI32: |
| return MachineType::Int32(); |
| case kMemU32: |
| return MachineType::Uint32(); |
| case kMemI64: |
| return MachineType::Int64(); |
| case kMemU64: |
| return MachineType::Uint64(); |
| case kMemF32: |
| return MachineType::Float32(); |
| case kMemF64: |
| return MachineType::Float64(); |
| default: |
| error(pc_ - 1, "invalid memory type"); |
| return MachineType::None(); |
| } |
| } |
| |
| // Parses a type entry, which is currently limited to functions only. |
| FunctionSig* consume_sig() { |
| const byte* pos = pc_; |
| byte form = consume_u8("type form"); |
| if (form != kWasmFunctionTypeForm) { |
| error(pos, pos, "expected function type form (0x%02x), got: 0x%02x", |
| kWasmFunctionTypeForm, form); |
| return nullptr; |
| } |
| int length; |
| // parse parameter types |
| uint32_t param_count = consume_u32v(&length, "param count"); |
| std::vector<LocalType> params; |
| for (uint32_t i = 0; i < param_count; i++) { |
| LocalType param = consume_local_type(); |
| if (param == kAstStmt) error(pc_ - 1, "invalid void parameter type"); |
| params.push_back(param); |
| } |
| |
| // parse return types |
| const byte* pt = pc_; |
| uint32_t return_count = consume_u32v(&length, "return count"); |
| if (return_count > kMaxReturnCount) { |
| error(pt, pt, "return count of %u exceeds maximum of %u", return_count, |
| kMaxReturnCount); |
| return nullptr; |
| } |
| std::vector<LocalType> returns; |
| for (uint32_t i = 0; i < return_count; i++) { |
| LocalType ret = consume_local_type(); |
| if (ret == kAstStmt) error(pc_ - 1, "invalid void return type"); |
| returns.push_back(ret); |
| } |
| |
| // FunctionSig stores the return types first. |
| LocalType* buffer = |
| module_zone->NewArray<LocalType>(param_count + return_count); |
| uint32_t b = 0; |
| for (uint32_t i = 0; i < return_count; i++) buffer[b++] = returns[i]; |
| for (uint32_t i = 0; i < param_count; i++) buffer[b++] = params[i]; |
| |
| return new (module_zone) FunctionSig(return_count, param_count, buffer); |
| } |
| }; |
| |
| // Helpers for nice error messages. |
| class ModuleError : public ModuleResult { |
| public: |
| explicit ModuleError(const char* msg) { |
| error_code = kError; |
| size_t len = strlen(msg) + 1; |
| char* result = new char[len]; |
| strncpy(result, msg, len); |
| result[len - 1] = 0; |
| error_msg.Reset(result); |
| } |
| }; |
| |
| // Helpers for nice error messages. |
| class FunctionError : public FunctionResult { |
| public: |
| explicit FunctionError(const char* msg) { |
| error_code = kError; |
| size_t len = strlen(msg) + 1; |
| char* result = new char[len]; |
| strncpy(result, msg, len); |
| result[len - 1] = 0; |
| error_msg.Reset(result); |
| } |
| }; |
| |
| ModuleResult DecodeWasmModule(Isolate* isolate, Zone* zone, |
| const byte* module_start, const byte* module_end, |
| bool verify_functions, ModuleOrigin origin) { |
| size_t decode_memory_start = zone->allocation_size(); |
| HistogramTimerScope wasm_decode_module_time_scope( |
| isolate->counters()->wasm_decode_module_time()); |
| size_t size = module_end - module_start; |
| if (module_start > module_end) return ModuleError("start > end"); |
| if (size >= kMaxModuleSize) return ModuleError("size > maximum module size"); |
| // TODO(bradnelson): Improve histogram handling of size_t. |
| isolate->counters()->wasm_module_size_bytes()->AddSample( |
| static_cast<int>(size)); |
| WasmModule* module = new WasmModule(); |
| ModuleDecoder decoder(zone, module_start, module_end, origin); |
| ModuleResult result = decoder.DecodeModule(module, verify_functions); |
| // TODO(bradnelson): Improve histogram handling of size_t. |
| isolate->counters()->wasm_decode_module_peak_memory_bytes()->AddSample( |
| static_cast<int>(zone->allocation_size() - decode_memory_start)); |
| return result; |
| } |
| |
| FunctionSig* DecodeWasmSignatureForTesting(Zone* zone, const byte* start, |
| const byte* end) { |
| ModuleDecoder decoder(zone, start, end, kWasmOrigin); |
| return decoder.DecodeFunctionSignature(start); |
| } |
| |
| FunctionResult DecodeWasmFunction(Isolate* isolate, Zone* zone, |
| ModuleEnv* module_env, |
| const byte* function_start, |
| const byte* function_end) { |
| HistogramTimerScope wasm_decode_function_time_scope( |
| isolate->counters()->wasm_decode_function_time()); |
| size_t size = function_end - function_start; |
| if (function_start > function_end) return FunctionError("start > end"); |
| if (size > kMaxFunctionSize) |
| return FunctionError("size > maximum function size"); |
| isolate->counters()->wasm_function_size_bytes()->AddSample( |
| static_cast<int>(size)); |
| WasmFunction* function = new WasmFunction(); |
| ModuleDecoder decoder(zone, function_start, function_end, kWasmOrigin); |
| return decoder.DecodeSingleFunction(module_env, function); |
| } |
| } // namespace wasm |
| } // namespace internal |
| } // namespace v8 |