// Copyright 2016 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. #if !V8_ENABLE_WEBASSEMBLY #error This header should only be included if WebAssembly is enabled. #endif // !V8_ENABLE_WEBASSEMBLY #ifndef V8_WASM_WASM_LIMITS_H_ #define V8_WASM_WASM_LIMITS_H_ #include <cstddef> #include <cstdint> #include <limits> #include "src/base/macros.h" #include "src/wasm/wasm-constants.h" namespace v8 { namespace internal { namespace wasm { // This constant limits the amount of *declared* memory. At runtime, memory can // only grow up to kV8MaxWasmMemoryPages. constexpr size_t kSpecMaxMemoryPages = 65536; // The following limits are imposed by V8 on WebAssembly modules. // The limits are agreed upon with other engines for consistency. constexpr size_t kV8MaxWasmTypes = 1000000; constexpr size_t kV8MaxWasmFunctions = 1000000; constexpr size_t kV8MaxWasmImports = 100000; constexpr size_t kV8MaxWasmExports = 100000; constexpr size_t kV8MaxWasmGlobals = 1000000; constexpr size_t kV8MaxWasmTags = 1000000; constexpr size_t kV8MaxWasmExceptionTypes = 1000000; constexpr size_t kV8MaxWasmDataSegments = 100000; // This indicates the maximum memory size our implementation supports. // Do not use this limit directly; use {max_mem_pages()} instead to take the // spec'ed limit as well as command line flag into account. // Also, do not use this limit to validate declared memory, use // kSpecMaxMemoryPages for that. constexpr size_t kV8MaxWasmMemoryPages = kSystemPointerSize == 4 ? 32767 // = 2 GiB : 65536; // = 4 GiB constexpr size_t kV8MaxWasmStringSize = 100000; constexpr size_t kV8MaxWasmModuleSize = 1024 * 1024 * 1024; // = 1 GiB constexpr size_t kV8MaxWasmFunctionSize = 7654321; constexpr size_t kV8MaxWasmFunctionLocals = 50000; constexpr size_t kV8MaxWasmFunctionParams = 1000; constexpr size_t kV8MaxWasmFunctionReturns = 1000; constexpr size_t kV8MaxWasmFunctionBrTableSize = 65520; // Don't use this limit directly, but use the value of FLAG_wasm_max_table_size. constexpr size_t kV8MaxWasmTableSize = 10000000; constexpr size_t kV8MaxWasmTableInitEntries = 10000000; constexpr size_t kV8MaxWasmTables = 100000; constexpr size_t kV8MaxWasmMemories = 1; // GC proposal. These limits are not standardized yet. constexpr size_t kV8MaxWasmStructFields = 999; constexpr uint32_t kV8MaxRttSubtypingDepth = 31; constexpr size_t kV8MaxWasmArrayInitLength = 999; static_assert(kV8MaxWasmTableSize <= 4294967295, // 2^32 - 1 "v8 should not exceed WebAssembly's non-web embedding limits"); static_assert(kV8MaxWasmTableInitEntries <= kV8MaxWasmTableSize, "JS-API should not exceed v8's limit"); constexpr uint64_t kWasmMaxHeapOffset = static_cast<uint64_t>( std::numeric_limits<uint32_t>::max()) // maximum base value + std::numeric_limits<uint32_t>::max(); // maximum index value // The following functions are defined in wasm-engine.cc. // Maximum number of pages we can allocate. This might be lower than the number // of pages that can be declared (e.g. as maximum): kSpecMaxMemoryPages. // TODO(wasm): Make this size_t for wasm64. Currently the --wasm-max-mem-pages // flag is only uint32_t. V8_EXPORT_PRIVATE uint32_t max_mem_pages(); inline uint64_t max_mem_bytes() { return uint64_t{max_mem_pages()} * kWasmPageSize; } uint32_t max_table_init_entries(); size_t max_module_size(); } // namespace wasm } // namespace internal } // namespace v8 #endif // V8_WASM_WASM_LIMITS_H_