| // 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. |
| |
| #if !V8_ENABLE_WEBASSEMBLY |
| #error This header should only be included if WebAssembly is enabled. |
| #endif // !V8_ENABLE_WEBASSEMBLY |
| |
| #ifndef V8_WASM_WASM_CONSTANTS_H_ |
| #define V8_WASM_WASM_CONSTANTS_H_ |
| |
| #include <cstddef> |
| #include <cstdint> |
| |
| #include "src/common/globals.h" |
| |
| namespace v8 { |
| namespace internal { |
| namespace wasm { |
| |
| // Binary encoding of the module header. |
| constexpr uint32_t kWasmMagic = 0x6d736100; |
| constexpr uint32_t kWasmVersion = 0x01; |
| |
| // Binary encoding of value and heap types. |
| enum ValueTypeCode : uint8_t { |
| // Current wasm types |
| kVoidCode = 0x40, |
| kI32Code = 0x7f, |
| kI64Code = 0x7e, |
| kF32Code = 0x7d, |
| kF64Code = 0x7c, |
| // Simd proposal |
| kS128Code = 0x7b, |
| // reftypes, typed-funcref, and GC proposals |
| kI8Code = 0x7a, |
| kI16Code = 0x79, |
| kFuncRefCode = 0x70, |
| kExternRefCode = 0x6f, |
| kAnyRefCode = 0x6e, |
| kEqRefCode = 0x6d, |
| kOptRefCode = 0x6c, |
| kRefCode = 0x6b, |
| kI31RefCode = 0x6a, |
| kRttWithDepthCode = 0x69, |
| kRttCode = 0x68, |
| kDataRefCode = 0x67, |
| }; |
| // Binary encoding of other types. |
| constexpr uint8_t kWasmFunctionTypeCode = 0x60; |
| constexpr uint8_t kWasmStructTypeCode = 0x5f; |
| constexpr uint8_t kWasmArrayTypeCode = 0x5e; |
| constexpr uint8_t kWasmFunctionExtendingTypeCode = 0x5d; |
| constexpr uint8_t kWasmStructExtendingTypeCode = 0x5c; |
| constexpr uint8_t kWasmArrayExtendingTypeCode = 0x5b; |
| |
| // Binary encoding of import/export kinds. |
| enum ImportExportKindCode : uint8_t { |
| kExternalFunction = 0, |
| kExternalTable = 1, |
| kExternalMemory = 2, |
| kExternalGlobal = 3, |
| kExternalTag = 4 |
| }; |
| |
| enum LimitsFlags : uint8_t { |
| kNoMaximum = 0x00, // Also valid for table limits. |
| kWithMaximum = 0x01, // Also valid for table limits. |
| kSharedNoMaximum = 0x02, // Only valid for memory limits. |
| kSharedWithMaximum = 0x03, // Only valid for memory limits. |
| kMemory64NoMaximum = 0x04, // Only valid for memory limits. |
| kMemory64WithMaximum = 0x05 // Only valid for memory limits. |
| }; |
| |
| // Flags for data and element segments. |
| enum SegmentFlags : uint8_t { |
| kActiveNoIndex = 0, // Active segment with a memory/table index of zero. |
| kPassive = 1, // Passive segment. |
| kActiveWithIndex = 2, // Active segment with a given memory/table index. |
| }; |
| |
| // Binary encoding of sections identifiers. |
| enum SectionCode : int8_t { |
| kUnknownSectionCode = 0, // code for unknown sections |
| kTypeSectionCode = 1, // Function signature declarations |
| kImportSectionCode = 2, // Import declarations |
| kFunctionSectionCode = 3, // Function declarations |
| kTableSectionCode = 4, // Indirect function table and others |
| kMemorySectionCode = 5, // Memory attributes |
| kGlobalSectionCode = 6, // Global declarations |
| kExportSectionCode = 7, // Exports |
| kStartSectionCode = 8, // Start function declaration |
| kElementSectionCode = 9, // Elements section |
| kCodeSectionCode = 10, // Function code |
| kDataSectionCode = 11, // Data segments |
| kDataCountSectionCode = 12, // Number of data segments |
| kTagSectionCode = 13, // Tag section |
| |
| // The following sections are custom sections, and are identified using a |
| // string rather than an integer. Their enumeration values are not guaranteed |
| // to be consistent. |
| kNameSectionCode, // Name section (encoded as a string) |
| kSourceMappingURLSectionCode, // Source Map URL section |
| kDebugInfoSectionCode, // DWARF section .debug_info |
| kExternalDebugInfoSectionCode, // Section encoding the external symbol path |
| kCompilationHintsSectionCode, // Compilation hints section |
| kBranchHintsSectionCode, // Branch hints section |
| |
| // Helper values |
| kFirstSectionInModule = kTypeSectionCode, |
| kLastKnownModuleSection = kBranchHintsSectionCode, |
| kFirstUnorderedSection = kDataCountSectionCode, |
| }; |
| |
| // Binary encoding of compilation hints. |
| constexpr uint8_t kDefaultCompilationHint = 0x0; |
| constexpr uint8_t kNoCompilationHint = kMaxUInt8; |
| |
| // Binary encoding of name section kinds. |
| enum NameSectionKindCode : uint8_t { |
| kModule = 0, |
| kFunction = 1, |
| kLocal = 2, |
| // https://github.com/WebAssembly/extended-name-section/ |
| kLabel = 3, |
| kType = 4, |
| kTable = 5, |
| kMemory = 6, |
| kGlobal = 7, |
| kElementSegment = 8, |
| kDataSegment = 9, |
| // https://github.com/WebAssembly/gc/issues/193 |
| kField = 10 |
| }; |
| |
| constexpr size_t kWasmPageSize = 0x10000; |
| constexpr uint32_t kWasmPageSizeLog2 = 16; |
| static_assert(kWasmPageSize == size_t{1} << kWasmPageSizeLog2, "consistency"); |
| |
| // TODO(wasm): Wrap WasmCodePosition in a struct. |
| using WasmCodePosition = int; |
| constexpr WasmCodePosition kNoCodePosition = -1; |
| |
| constexpr uint32_t kExceptionAttribute = 0; |
| |
| constexpr int kAnonymousFuncIndex = -1; |
| |
| // The number of calls to an exported Wasm function that will be handled |
| // by the generic wrapper. Once the budget is exhausted, a specific wrapper |
| // is to be compiled for the function's signature. |
| // The abstract goal of the tiering strategy for the js-to-wasm wrappers is to |
| // use the generic wrapper as much as possible (less space, no need to compile), |
| // but fall back to compiling a specific wrapper for any function (signature) |
| // that is used often enough for the generic wrapper's small execution penalty |
| // to start adding up. |
| // So, when choosing a value for the initial budget, we are interested in a |
| // value that skips on tiering up functions that are called only a few times and |
| // the tier-up only wastes resources, but triggers compilation of specific |
| // wrappers early on for those functions that have the potential to be called |
| // often enough. |
| constexpr uint32_t kGenericWrapperBudget = 1000; |
| |
| #if V8_TARGET_ARCH_X64 |
| constexpr int32_t kOSRTargetOffset = 3 * kSystemPointerSize; |
| #endif |
| |
| } // namespace wasm |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_WASM_WASM_CONSTANTS_H_ |