1 //===- WriterUtils.cpp ----------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "WriterUtils.h" 10 #include "lld/Common/ErrorHandler.h" 11 #include "llvm/Support/Debug.h" 12 #include "llvm/Support/EndianStream.h" 13 #include "llvm/Support/LEB128.h" 14 15 #define DEBUG_TYPE "lld" 16 17 using namespace llvm; 18 using namespace llvm::wasm; 19 20 namespace lld { 21 std::string toString(ValType type) { 22 switch (type) { 23 case ValType::I32: 24 return "i32"; 25 case ValType::I64: 26 return "i64"; 27 case ValType::F32: 28 return "f32"; 29 case ValType::F64: 30 return "f64"; 31 case ValType::V128: 32 return "v128"; 33 case ValType::EXNREF: 34 return "exnref"; 35 } 36 llvm_unreachable("Invalid wasm::ValType"); 37 } 38 39 std::string toString(const WasmSignature &sig) { 40 SmallString<128> s("("); 41 for (ValType type : sig.Params) { 42 if (s.size() != 1) 43 s += ", "; 44 s += toString(type); 45 } 46 s += ") -> "; 47 if (sig.Returns.empty()) 48 s += "void"; 49 else 50 s += toString(sig.Returns[0]); 51 return s.str(); 52 } 53 54 std::string toString(const WasmGlobalType &type) { 55 return (type.Mutable ? "var " : "const ") + 56 toString(static_cast<ValType>(type.Type)); 57 } 58 59 std::string toString(const WasmEventType &type) { 60 if (type.Attribute == WASM_EVENT_ATTRIBUTE_EXCEPTION) 61 return "exception"; 62 return "unknown"; 63 } 64 65 namespace wasm { 66 void debugWrite(uint64_t offset, const Twine &msg) { 67 LLVM_DEBUG(dbgs() << format(" | %08lld: ", offset) << msg << "\n"); 68 } 69 70 void writeUleb128(raw_ostream &os, uint32_t number, const Twine &msg) { 71 debugWrite(os.tell(), msg + "[" + utohexstr(number) + "]"); 72 encodeULEB128(number, os); 73 } 74 75 void writeSleb128(raw_ostream &os, int32_t number, const Twine &msg) { 76 debugWrite(os.tell(), msg + "[" + utohexstr(number) + "]"); 77 encodeSLEB128(number, os); 78 } 79 80 void writeBytes(raw_ostream &os, const char *bytes, size_t count, 81 const Twine &msg) { 82 debugWrite(os.tell(), msg + " [data[" + Twine(count) + "]]"); 83 os.write(bytes, count); 84 } 85 86 void writeStr(raw_ostream &os, StringRef string, const Twine &msg) { 87 debugWrite(os.tell(), 88 msg + " [str[" + Twine(string.size()) + "]: " + string + "]"); 89 encodeULEB128(string.size(), os); 90 os.write(string.data(), string.size()); 91 } 92 93 void writeU8(raw_ostream &os, uint8_t byte, const Twine &msg) { 94 debugWrite(os.tell(), msg + " [0x" + utohexstr(byte) + "]"); 95 os << byte; 96 } 97 98 void writeU32(raw_ostream &os, uint32_t number, const Twine &msg) { 99 debugWrite(os.tell(), msg + "[0x" + utohexstr(number) + "]"); 100 support::endian::write(os, number, support::little); 101 } 102 103 void writeValueType(raw_ostream &os, ValType type, const Twine &msg) { 104 writeU8(os, static_cast<uint8_t>(type), 105 msg + "[type: " + toString(type) + "]"); 106 } 107 108 void writeSig(raw_ostream &os, const WasmSignature &sig) { 109 writeU8(os, WASM_TYPE_FUNC, "signature type"); 110 writeUleb128(os, sig.Params.size(), "param Count"); 111 for (ValType paramType : sig.Params) { 112 writeValueType(os, paramType, "param type"); 113 } 114 writeUleb128(os, sig.Returns.size(), "result Count"); 115 if (sig.Returns.size()) { 116 writeValueType(os, sig.Returns[0], "result type"); 117 } 118 } 119 120 void writeI32Const(raw_ostream &os, int32_t number, const Twine &msg) { 121 writeU8(os, WASM_OPCODE_I32_CONST, "i32.const"); 122 writeSleb128(os, number, msg); 123 } 124 125 void writeI64Const(raw_ostream &os, int32_t number, const Twine &msg) { 126 writeU8(os, WASM_OPCODE_I64_CONST, "i64.const"); 127 writeSleb128(os, number, msg); 128 } 129 130 void writeMemArg(raw_ostream &os, uint32_t alignment, uint32_t offset) { 131 writeUleb128(os, alignment, "alignment"); 132 writeUleb128(os, offset, "offset"); 133 } 134 135 void writeInitExpr(raw_ostream &os, const WasmInitExpr &initExpr) { 136 writeU8(os, initExpr.Opcode, "opcode"); 137 switch (initExpr.Opcode) { 138 case WASM_OPCODE_I32_CONST: 139 writeSleb128(os, initExpr.Value.Int32, "literal (i32)"); 140 break; 141 case WASM_OPCODE_I64_CONST: 142 writeSleb128(os, initExpr.Value.Int64, "literal (i64)"); 143 break; 144 case WASM_OPCODE_GLOBAL_GET: 145 writeUleb128(os, initExpr.Value.Global, "literal (global index)"); 146 break; 147 default: 148 fatal("unknown opcode in init expr: " + Twine(initExpr.Opcode)); 149 } 150 writeU8(os, WASM_OPCODE_END, "opcode:end"); 151 } 152 153 void writeLimits(raw_ostream &os, const WasmLimits &limits) { 154 writeU8(os, limits.Flags, "limits flags"); 155 writeUleb128(os, limits.Initial, "limits initial"); 156 if (limits.Flags & WASM_LIMITS_FLAG_HAS_MAX) 157 writeUleb128(os, limits.Maximum, "limits max"); 158 } 159 160 void writeGlobalType(raw_ostream &os, const WasmGlobalType &type) { 161 // TODO: Update WasmGlobalType to use ValType and remove this cast. 162 writeValueType(os, ValType(type.Type), "global type"); 163 writeU8(os, type.Mutable, "global mutable"); 164 } 165 166 void writeGlobal(raw_ostream &os, const WasmGlobal &global) { 167 writeGlobalType(os, global.Type); 168 writeInitExpr(os, global.InitExpr); 169 } 170 171 void writeEventType(raw_ostream &os, const WasmEventType &type) { 172 writeUleb128(os, type.Attribute, "event attribute"); 173 writeUleb128(os, type.SigIndex, "sig index"); 174 } 175 176 void writeEvent(raw_ostream &os, const WasmEvent &event) { 177 writeEventType(os, event.Type); 178 } 179 180 void writeTableType(raw_ostream &os, const llvm::wasm::WasmTable &type) { 181 writeU8(os, WASM_TYPE_FUNCREF, "table type"); 182 writeLimits(os, type.Limits); 183 } 184 185 void writeImport(raw_ostream &os, const WasmImport &import) { 186 writeStr(os, import.Module, "import module name"); 187 writeStr(os, import.Field, "import field name"); 188 writeU8(os, import.Kind, "import kind"); 189 switch (import.Kind) { 190 case WASM_EXTERNAL_FUNCTION: 191 writeUleb128(os, import.SigIndex, "import sig index"); 192 break; 193 case WASM_EXTERNAL_GLOBAL: 194 writeGlobalType(os, import.Global); 195 break; 196 case WASM_EXTERNAL_EVENT: 197 writeEventType(os, import.Event); 198 break; 199 case WASM_EXTERNAL_MEMORY: 200 writeLimits(os, import.Memory); 201 break; 202 case WASM_EXTERNAL_TABLE: 203 writeTableType(os, import.Table); 204 break; 205 default: 206 fatal("unsupported import type: " + Twine(import.Kind)); 207 } 208 } 209 210 void writeExport(raw_ostream &os, const WasmExport &export_) { 211 writeStr(os, export_.Name, "export name"); 212 writeU8(os, export_.Kind, "export kind"); 213 switch (export_.Kind) { 214 case WASM_EXTERNAL_FUNCTION: 215 writeUleb128(os, export_.Index, "function index"); 216 break; 217 case WASM_EXTERNAL_GLOBAL: 218 writeUleb128(os, export_.Index, "global index"); 219 break; 220 case WASM_EXTERNAL_MEMORY: 221 writeUleb128(os, export_.Index, "memory index"); 222 break; 223 case WASM_EXTERNAL_TABLE: 224 writeUleb128(os, export_.Index, "table index"); 225 break; 226 default: 227 fatal("unsupported export type: " + Twine(export_.Kind)); 228 } 229 } 230 231 } // namespace wasm 232 } // namespace lld 233