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 {
toString(ValType type)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 case ValType::FUNCREF:
36 return "funcref";
37 case ValType::EXTERNREF:
38 return "externref";
39 }
40 llvm_unreachable("Invalid wasm::ValType");
41 }
42
toString(const WasmSignature & sig)43 std::string toString(const WasmSignature &sig) {
44 SmallString<128> s("(");
45 for (ValType type : sig.Params) {
46 if (s.size() != 1)
47 s += ", ";
48 s += toString(type);
49 }
50 s += ") -> ";
51 if (sig.Returns.empty())
52 s += "void";
53 else
54 s += toString(sig.Returns[0]);
55 return std::string(s.str());
56 }
57
toString(const WasmGlobalType & type)58 std::string toString(const WasmGlobalType &type) {
59 return (type.Mutable ? "var " : "const ") +
60 toString(static_cast<ValType>(type.Type));
61 }
62
toString(const WasmEventType & type)63 std::string toString(const WasmEventType &type) {
64 if (type.Attribute == WASM_EVENT_ATTRIBUTE_EXCEPTION)
65 return "exception";
66 return "unknown";
67 }
68
69 namespace wasm {
debugWrite(uint64_t offset,const Twine & msg)70 void debugWrite(uint64_t offset, const Twine &msg) {
71 LLVM_DEBUG(dbgs() << format(" | %08lld: ", offset) << msg << "\n");
72 }
73
writeUleb128(raw_ostream & os,uint64_t number,const Twine & msg)74 void writeUleb128(raw_ostream &os, uint64_t number, const Twine &msg) {
75 debugWrite(os.tell(), msg + "[" + utohexstr(number) + "]");
76 encodeULEB128(number, os);
77 }
78
writeSleb128(raw_ostream & os,int64_t number,const Twine & msg)79 void writeSleb128(raw_ostream &os, int64_t number, const Twine &msg) {
80 debugWrite(os.tell(), msg + "[" + utohexstr(number) + "]");
81 encodeSLEB128(number, os);
82 }
83
writeBytes(raw_ostream & os,const char * bytes,size_t count,const Twine & msg)84 void writeBytes(raw_ostream &os, const char *bytes, size_t count,
85 const Twine &msg) {
86 debugWrite(os.tell(), msg + " [data[" + Twine(count) + "]]");
87 os.write(bytes, count);
88 }
89
writeStr(raw_ostream & os,StringRef string,const Twine & msg)90 void writeStr(raw_ostream &os, StringRef string, const Twine &msg) {
91 debugWrite(os.tell(),
92 msg + " [str[" + Twine(string.size()) + "]: " + string + "]");
93 encodeULEB128(string.size(), os);
94 os.write(string.data(), string.size());
95 }
96
writeU8(raw_ostream & os,uint8_t byte,const Twine & msg)97 void writeU8(raw_ostream &os, uint8_t byte, const Twine &msg) {
98 debugWrite(os.tell(), msg + " [0x" + utohexstr(byte) + "]");
99 os << byte;
100 }
101
writeU32(raw_ostream & os,uint32_t number,const Twine & msg)102 void writeU32(raw_ostream &os, uint32_t number, const Twine &msg) {
103 debugWrite(os.tell(), msg + "[0x" + utohexstr(number) + "]");
104 support::endian::write(os, number, support::little);
105 }
106
writeU64(raw_ostream & os,uint64_t number,const Twine & msg)107 void writeU64(raw_ostream &os, uint64_t number, const Twine &msg) {
108 debugWrite(os.tell(), msg + "[0x" + utohexstr(number) + "]");
109 support::endian::write(os, number, support::little);
110 }
111
writeValueType(raw_ostream & os,ValType type,const Twine & msg)112 void writeValueType(raw_ostream &os, ValType type, const Twine &msg) {
113 writeU8(os, static_cast<uint8_t>(type),
114 msg + "[type: " + toString(type) + "]");
115 }
116
writeSig(raw_ostream & os,const WasmSignature & sig)117 void writeSig(raw_ostream &os, const WasmSignature &sig) {
118 writeU8(os, WASM_TYPE_FUNC, "signature type");
119 writeUleb128(os, sig.Params.size(), "param Count");
120 for (ValType paramType : sig.Params) {
121 writeValueType(os, paramType, "param type");
122 }
123 writeUleb128(os, sig.Returns.size(), "result Count");
124 for (ValType returnType : sig.Returns) {
125 writeValueType(os, returnType, "result type");
126 }
127 }
128
writeI32Const(raw_ostream & os,int32_t number,const Twine & msg)129 void writeI32Const(raw_ostream &os, int32_t number, const Twine &msg) {
130 writeU8(os, WASM_OPCODE_I32_CONST, "i32.const");
131 writeSleb128(os, number, msg);
132 }
133
writeI64Const(raw_ostream & os,int64_t number,const Twine & msg)134 void writeI64Const(raw_ostream &os, int64_t number, const Twine &msg) {
135 writeU8(os, WASM_OPCODE_I64_CONST, "i64.const");
136 writeSleb128(os, number, msg);
137 }
138
writePtrConst(raw_ostream & os,int64_t number,bool is64,const Twine & msg)139 void writePtrConst(raw_ostream &os, int64_t number, bool is64,
140 const Twine &msg) {
141 if (is64)
142 writeI64Const(os, number, msg);
143 else
144 writeI32Const(os, static_cast<int32_t>(number), msg);
145 }
146
writeMemArg(raw_ostream & os,uint32_t alignment,uint64_t offset)147 void writeMemArg(raw_ostream &os, uint32_t alignment, uint64_t offset) {
148 writeUleb128(os, alignment, "alignment");
149 writeUleb128(os, offset, "offset");
150 }
151
writeInitExpr(raw_ostream & os,const WasmInitExpr & initExpr)152 void writeInitExpr(raw_ostream &os, const WasmInitExpr &initExpr) {
153 writeU8(os, initExpr.Opcode, "opcode");
154 switch (initExpr.Opcode) {
155 case WASM_OPCODE_I32_CONST:
156 writeSleb128(os, initExpr.Value.Int32, "literal (i32)");
157 break;
158 case WASM_OPCODE_I64_CONST:
159 writeSleb128(os, initExpr.Value.Int64, "literal (i64)");
160 break;
161 case WASM_OPCODE_F32_CONST:
162 writeU32(os, initExpr.Value.Float32, "literal (f32)");
163 break;
164 case WASM_OPCODE_F64_CONST:
165 writeU64(os, initExpr.Value.Float64, "literal (f64)");
166 break;
167 case WASM_OPCODE_GLOBAL_GET:
168 writeUleb128(os, initExpr.Value.Global, "literal (global index)");
169 break;
170 case WASM_OPCODE_REF_NULL:
171 writeValueType(os, ValType::EXTERNREF, "literal (externref type)");
172 break;
173 default:
174 fatal("unknown opcode in init expr: " + Twine(initExpr.Opcode));
175 }
176 writeU8(os, WASM_OPCODE_END, "opcode:end");
177 }
178
writeLimits(raw_ostream & os,const WasmLimits & limits)179 void writeLimits(raw_ostream &os, const WasmLimits &limits) {
180 writeU8(os, limits.Flags, "limits flags");
181 writeUleb128(os, limits.Initial, "limits initial");
182 if (limits.Flags & WASM_LIMITS_FLAG_HAS_MAX)
183 writeUleb128(os, limits.Maximum, "limits max");
184 }
185
writeGlobalType(raw_ostream & os,const WasmGlobalType & type)186 void writeGlobalType(raw_ostream &os, const WasmGlobalType &type) {
187 // TODO: Update WasmGlobalType to use ValType and remove this cast.
188 writeValueType(os, ValType(type.Type), "global type");
189 writeU8(os, type.Mutable, "global mutable");
190 }
191
writeGlobal(raw_ostream & os,const WasmGlobal & global)192 void writeGlobal(raw_ostream &os, const WasmGlobal &global) {
193 writeGlobalType(os, global.Type);
194 writeInitExpr(os, global.InitExpr);
195 }
196
writeEventType(raw_ostream & os,const WasmEventType & type)197 void writeEventType(raw_ostream &os, const WasmEventType &type) {
198 writeUleb128(os, type.Attribute, "event attribute");
199 writeUleb128(os, type.SigIndex, "sig index");
200 }
201
writeEvent(raw_ostream & os,const WasmEvent & event)202 void writeEvent(raw_ostream &os, const WasmEvent &event) {
203 writeEventType(os, event.Type);
204 }
205
writeTableType(raw_ostream & os,const WasmTableType & type)206 void writeTableType(raw_ostream &os, const WasmTableType &type) {
207 writeU8(os, WASM_TYPE_FUNCREF, "table type");
208 writeLimits(os, type.Limits);
209 }
210
writeImport(raw_ostream & os,const WasmImport & import)211 void writeImport(raw_ostream &os, const WasmImport &import) {
212 writeStr(os, import.Module, "import module name");
213 writeStr(os, import.Field, "import field name");
214 writeU8(os, import.Kind, "import kind");
215 switch (import.Kind) {
216 case WASM_EXTERNAL_FUNCTION:
217 writeUleb128(os, import.SigIndex, "import sig index");
218 break;
219 case WASM_EXTERNAL_GLOBAL:
220 writeGlobalType(os, import.Global);
221 break;
222 case WASM_EXTERNAL_EVENT:
223 writeEventType(os, import.Event);
224 break;
225 case WASM_EXTERNAL_MEMORY:
226 writeLimits(os, import.Memory);
227 break;
228 case WASM_EXTERNAL_TABLE:
229 writeTableType(os, import.Table);
230 break;
231 default:
232 fatal("unsupported import type: " + Twine(import.Kind));
233 }
234 }
235
writeExport(raw_ostream & os,const WasmExport & export_)236 void writeExport(raw_ostream &os, const WasmExport &export_) {
237 writeStr(os, export_.Name, "export name");
238 writeU8(os, export_.Kind, "export kind");
239 switch (export_.Kind) {
240 case WASM_EXTERNAL_FUNCTION:
241 writeUleb128(os, export_.Index, "function index");
242 break;
243 case WASM_EXTERNAL_GLOBAL:
244 writeUleb128(os, export_.Index, "global index");
245 break;
246 case WASM_EXTERNAL_EVENT:
247 writeUleb128(os, export_.Index, "event index");
248 break;
249 case WASM_EXTERNAL_MEMORY:
250 writeUleb128(os, export_.Index, "memory index");
251 break;
252 case WASM_EXTERNAL_TABLE:
253 writeUleb128(os, export_.Index, "table index");
254 break;
255 default:
256 fatal("unsupported export type: " + Twine(export_.Kind));
257 }
258 }
259
260 } // namespace wasm
261 } // namespace lld
262