1 // Copyright 2017 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #if !V8_ENABLE_WEBASSEMBLY 6 #error This header should only be included if WebAssembly is enabled. 7 #endif // !V8_ENABLE_WEBASSEMBLY 8 9 #ifndef V8_WASM_LOCAL_DECL_ENCODER_H_ 10 #define V8_WASM_LOCAL_DECL_ENCODER_H_ 11 12 #include "src/common/globals.h" 13 #include "src/wasm/wasm-opcodes.h" 14 #include "src/zone/zone-containers.h" 15 #include "src/zone/zone.h" 16 17 namespace v8 { 18 namespace internal { 19 namespace wasm { 20 21 // A helper for encoding local declarations prepended to the body of a function. 22 class V8_EXPORT_PRIVATE LocalDeclEncoder { 23 public: 24 explicit LocalDeclEncoder(Zone* zone, const FunctionSig* s = nullptr) sig(s)25 : sig(s), local_decls(zone), total(0) {} 26 27 // Prepend local declarations by creating a new buffer and copying data 28 // over. The new buffer must be delete[]'d by the caller. 29 void Prepend(Zone* zone, const byte** start, const byte** end) const; 30 31 size_t Emit(byte* buffer) const; 32 33 // Add locals declarations to this helper. Return the index of the newly added 34 // local(s), with an optional adjustment for the parameters. 35 uint32_t AddLocals(uint32_t count, ValueType type); 36 37 size_t Size() const; 38 has_sig()39 bool has_sig() const { return sig != nullptr; } get_sig()40 const FunctionSig* get_sig() const { return sig; } set_sig(const FunctionSig * s)41 void set_sig(const FunctionSig* s) { sig = s; } 42 43 private: 44 const FunctionSig* sig; 45 ZoneVector<std::pair<uint32_t, ValueType>> local_decls; 46 size_t total; 47 }; 48 49 } // namespace wasm 50 } // namespace internal 51 } // namespace v8 52 53 #endif // V8_WASM_LOCAL_DECL_ENCODER_H_ 54