| // 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::internal::wasm { |
| |
| // These constants limit the amount of *declared* memory. At runtime, memory can |
| // only grow up to kV8MaxWasmMemory{32,64}Pages. |
| constexpr size_t kSpecMaxMemory32Pages = 65'536; // 4GB |
| // TODO(clemensb): Adapt once the spec defines a limit here. For now, use 16GB. |
| constexpr size_t kSpecMaxMemory64Pages = 262'144; // 16GB |
| |
| // The following limits are imposed by V8 on WebAssembly modules. |
| // The limits are agreed upon with other engines for consistency. |
| constexpr size_t kV8MaxWasmTypes = 1'000'000; |
| constexpr size_t kV8MaxWasmFunctions = 1'000'000; |
| constexpr size_t kV8MaxWasmImports = 100'000; |
| constexpr size_t kV8MaxWasmExports = 100'000; |
| constexpr size_t kV8MaxWasmGlobals = 1'000'000; |
| constexpr size_t kV8MaxWasmTags = 1'000'000; |
| constexpr size_t kV8MaxWasmExceptionTypes = 1'000'000; |
| constexpr size_t kV8MaxWasmDataSegments = 100'000; |
| // This indicates the maximum memory size our implementation supports. |
| // Do not use this limit directly; use {max_mem{32,64}_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 |
| // kSpecMaxMemory{32,64}Pages for that. |
| constexpr size_t kV8MaxWasmMemory32Pages = kSystemPointerSize == 4 |
| ? 32'767 // = 2 GiB - 64Kib |
| : 65'536; // = 4 GiB |
| constexpr size_t kV8MaxWasmMemory64Pages = kSystemPointerSize == 4 |
| ? 32'767 // = 2 GiB - 64Kib |
| : 262'144; // = 16 GiB |
| constexpr size_t kV8MaxWasmStringSize = 100'000; |
| constexpr size_t kV8MaxWasmModuleSize = 1024 * 1024 * 1024; // = 1 GiB |
| constexpr size_t kV8MaxWasmFunctionSize = 7'654'321; |
| constexpr size_t kV8MaxWasmFunctionLocals = 50'000; |
| constexpr size_t kV8MaxWasmFunctionParams = 1'000; |
| constexpr size_t kV8MaxWasmFunctionReturns = 1'000; |
| constexpr size_t kV8MaxWasmFunctionBrTableSize = 65'520; |
| // Don't use this limit directly, but use the value of |
| // v8_flags.wasm_max_table_size. |
| constexpr size_t kV8MaxWasmTableSize = 10'000'000; |
| constexpr size_t kV8MaxWasmTableInitEntries = 10'000'000; |
| constexpr size_t kV8MaxWasmTables = 100'000; |
| constexpr size_t kV8MaxWasmMemories = 100'000; |
| |
| // GC proposal. |
| constexpr size_t kV8MaxWasmStructFields = 10'000; |
| constexpr uint32_t kV8MaxRttSubtypingDepth = 63; |
| constexpr size_t kV8MaxWasmArrayNewFixedLength = 10'000; |
| |
| // Stringref proposal. This limit is not standardized yet. |
| constexpr size_t kV8MaxWasmStringLiterals = 1'000'000; |
| |
| 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, for memory32 and memory64. This |
| // might be lower than the number of pages that can be declared (e.g. as |
| // maximum): kSpecMaxMemory{32,64}Pages. |
| // Even for 64-bit memory, the number of pages is still a 32-bit number for now, |
| // which allows for up to 128 TB memories (2**31 * 64k). |
| static_assert(kV8MaxWasmMemory64Pages <= kMaxUInt32); |
| V8_EXPORT_PRIVATE uint32_t max_mem32_pages(); |
| V8_EXPORT_PRIVATE uint32_t max_mem64_pages(); |
| |
| inline uint64_t max_mem32_bytes() { |
| return uint64_t{max_mem32_pages()} * kWasmPageSize; |
| } |
| |
| inline uint64_t max_mem64_bytes() { |
| return uint64_t{max_mem64_pages()} * kWasmPageSize; |
| } |
| |
| V8_EXPORT_PRIVATE uint32_t max_table_init_entries(); |
| V8_EXPORT_PRIVATE size_t max_module_size(); |
| |
| } // namespace v8::internal::wasm |
| |
| #endif // V8_WASM_WASM_LIMITS_H_ |