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comparison: gfx/angle/src/compiler/preprocessor/MacroExpander.cpp
gfx/angle/src/compiler/preprocessor/MacroExpander.cpp
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- TOR_BUG_9701
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| -1:000000000000 | 0:99d3535a6e29 |
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| 1 // | |
| 2 // Copyright (c) 2011 The ANGLE Project Authors. All rights reserved. | |
| 3 // Use of this source code is governed by a BSD-style license that can be | |
| 4 // found in the LICENSE file. | |
| 5 // | |
| 6 | |
| 7 #include "MacroExpander.h" | |
| 8 | |
| 9 #include <algorithm> | |
| 10 #include <sstream> | |
| 11 | |
| 12 #include "DiagnosticsBase.h" | |
| 13 #include "Token.h" | |
| 14 | |
| 15 namespace pp | |
| 16 { | |
| 17 | |
| 18 class TokenLexer : public Lexer | |
| 19 { | |
| 20 public: | |
| 21 typedef std::vector<Token> TokenVector; | |
| 22 | |
| 23 TokenLexer(TokenVector* tokens) | |
| 24 { | |
| 25 tokens->swap(mTokens); | |
| 26 mIter = mTokens.begin(); | |
| 27 } | |
| 28 | |
| 29 virtual void lex(Token* token) | |
| 30 { | |
| 31 if (mIter == mTokens.end()) | |
| 32 { | |
| 33 token->reset(); | |
| 34 token->type = Token::LAST; | |
| 35 } | |
| 36 else | |
| 37 { | |
| 38 *token = *mIter++; | |
| 39 } | |
| 40 } | |
| 41 | |
| 42 private: | |
| 43 PP_DISALLOW_COPY_AND_ASSIGN(TokenLexer); | |
| 44 | |
| 45 TokenVector mTokens; | |
| 46 TokenVector::const_iterator mIter; | |
| 47 }; | |
| 48 | |
| 49 MacroExpander::MacroExpander(Lexer* lexer, | |
| 50 MacroSet* macroSet, | |
| 51 Diagnostics* diagnostics) : | |
| 52 mLexer(lexer), | |
| 53 mMacroSet(macroSet), | |
| 54 mDiagnostics(diagnostics) | |
| 55 { | |
| 56 } | |
| 57 | |
| 58 MacroExpander::~MacroExpander() | |
| 59 { | |
| 60 for (std::size_t i = 0; i < mContextStack.size(); ++i) | |
| 61 { | |
| 62 delete mContextStack[i]; | |
| 63 } | |
| 64 } | |
| 65 | |
| 66 void MacroExpander::lex(Token* token) | |
| 67 { | |
| 68 while (true) | |
| 69 { | |
| 70 getToken(token); | |
| 71 | |
| 72 if (token->type != Token::IDENTIFIER) | |
| 73 break; | |
| 74 | |
| 75 if (token->expansionDisabled()) | |
| 76 break; | |
| 77 | |
| 78 MacroSet::const_iterator iter = mMacroSet->find(token->text); | |
| 79 if (iter == mMacroSet->end()) | |
| 80 break; | |
| 81 | |
| 82 const Macro& macro = iter->second; | |
| 83 if (macro.disabled) | |
| 84 { | |
| 85 // If a particular token is not expanded, it is never expanded. | |
| 86 token->setExpansionDisabled(true); | |
| 87 break; | |
| 88 } | |
| 89 if ((macro.type == Macro::kTypeFunc) && !isNextTokenLeftParen()) | |
| 90 { | |
| 91 // If the token immediately after the macro name is not a '(', | |
| 92 // this macro should not be expanded. | |
| 93 break; | |
| 94 } | |
| 95 | |
| 96 pushMacro(macro, *token); | |
| 97 } | |
| 98 } | |
| 99 | |
| 100 void MacroExpander::getToken(Token* token) | |
| 101 { | |
| 102 if (mReserveToken.get()) | |
| 103 { | |
| 104 *token = *mReserveToken; | |
| 105 mReserveToken.reset(); | |
| 106 return; | |
| 107 } | |
| 108 | |
| 109 // First pop all empty macro contexts. | |
| 110 while (!mContextStack.empty() && mContextStack.back()->empty()) | |
| 111 { | |
| 112 popMacro(); | |
| 113 } | |
| 114 | |
| 115 if (!mContextStack.empty()) | |
| 116 { | |
| 117 *token = mContextStack.back()->get(); | |
| 118 } | |
| 119 else | |
| 120 { | |
| 121 mLexer->lex(token); | |
| 122 } | |
| 123 } | |
| 124 | |
| 125 void MacroExpander::ungetToken(const Token& token) | |
| 126 { | |
| 127 if (!mContextStack.empty()) | |
| 128 { | |
| 129 MacroContext* context = mContextStack.back(); | |
| 130 context->unget(); | |
| 131 assert(context->replacements[context->index] == token); | |
| 132 } | |
| 133 else | |
| 134 { | |
| 135 assert(!mReserveToken.get()); | |
| 136 mReserveToken.reset(new Token(token)); | |
| 137 } | |
| 138 } | |
| 139 | |
| 140 bool MacroExpander::isNextTokenLeftParen() | |
| 141 { | |
| 142 Token token; | |
| 143 getToken(&token); | |
| 144 | |
| 145 bool lparen = token.type == '('; | |
| 146 ungetToken(token); | |
| 147 | |
| 148 return lparen; | |
| 149 } | |
| 150 | |
| 151 bool MacroExpander::pushMacro(const Macro& macro, const Token& identifier) | |
| 152 { | |
| 153 assert(!macro.disabled); | |
| 154 assert(!identifier.expansionDisabled()); | |
| 155 assert(identifier.type == Token::IDENTIFIER); | |
| 156 assert(identifier.text == macro.name); | |
| 157 | |
| 158 std::vector<Token> replacements; | |
| 159 if (!expandMacro(macro, identifier, &replacements)) | |
| 160 return false; | |
| 161 | |
| 162 // Macro is disabled for expansion until it is popped off the stack. | |
| 163 macro.disabled = true; | |
| 164 | |
| 165 MacroContext* context = new MacroContext; | |
| 166 context->macro = ¯o; | |
| 167 context->replacements.swap(replacements); | |
| 168 mContextStack.push_back(context); | |
| 169 return true; | |
| 170 } | |
| 171 | |
| 172 void MacroExpander::popMacro() | |
| 173 { | |
| 174 assert(!mContextStack.empty()); | |
| 175 | |
| 176 MacroContext* context = mContextStack.back(); | |
| 177 mContextStack.pop_back(); | |
| 178 | |
| 179 assert(context->empty()); | |
| 180 assert(context->macro->disabled); | |
| 181 context->macro->disabled = false; | |
| 182 delete context; | |
| 183 } | |
| 184 | |
| 185 bool MacroExpander::expandMacro(const Macro& macro, | |
| 186 const Token& identifier, | |
| 187 std::vector<Token>* replacements) | |
| 188 { | |
| 189 replacements->clear(); | |
| 190 if (macro.type == Macro::kTypeObj) | |
| 191 { | |
| 192 replacements->assign(macro.replacements.begin(), | |
| 193 macro.replacements.end()); | |
| 194 | |
| 195 if (macro.predefined) | |
| 196 { | |
| 197 static const std::string kLine = "__LINE__"; | |
| 198 static const std::string kFile = "__FILE__"; | |
| 199 | |
| 200 assert(replacements->size() == 1); | |
| 201 Token& repl = replacements->front(); | |
| 202 if (macro.name == kLine) | |
| 203 { | |
| 204 std::ostringstream stream; | |
| 205 stream << identifier.location.line; | |
| 206 repl.text = stream.str(); | |
| 207 } | |
| 208 else if (macro.name == kFile) | |
| 209 { | |
| 210 std::ostringstream stream; | |
| 211 stream << identifier.location.file; | |
| 212 repl.text = stream.str(); | |
| 213 } | |
| 214 } | |
| 215 } | |
| 216 else | |
| 217 { | |
| 218 assert(macro.type == Macro::kTypeFunc); | |
| 219 std::vector<MacroArg> args; | |
| 220 args.reserve(macro.parameters.size()); | |
| 221 if (!collectMacroArgs(macro, identifier, &args)) | |
| 222 return false; | |
| 223 | |
| 224 replaceMacroParams(macro, args, replacements); | |
| 225 } | |
| 226 | |
| 227 for (std::size_t i = 0; i < replacements->size(); ++i) | |
| 228 { | |
| 229 Token& repl = replacements->at(i); | |
| 230 if (i == 0) | |
| 231 { | |
| 232 // The first token in the replacement list inherits the padding | |
| 233 // properties of the identifier token. | |
| 234 repl.setAtStartOfLine(identifier.atStartOfLine()); | |
| 235 repl.setHasLeadingSpace(identifier.hasLeadingSpace()); | |
| 236 } | |
| 237 repl.location = identifier.location; | |
| 238 } | |
| 239 return true; | |
| 240 } | |
| 241 | |
| 242 bool MacroExpander::collectMacroArgs(const Macro& macro, | |
| 243 const Token& identifier, | |
| 244 std::vector<MacroArg>* args) | |
| 245 { | |
| 246 Token token; | |
| 247 getToken(&token); | |
| 248 assert(token.type == '('); | |
| 249 | |
| 250 args->push_back(MacroArg()); | |
| 251 for (int openParens = 1; openParens != 0; ) | |
| 252 { | |
| 253 getToken(&token); | |
| 254 | |
| 255 if (token.type == Token::LAST) | |
| 256 { | |
| 257 mDiagnostics->report(Diagnostics::MACRO_UNTERMINATED_INVOCATION, | |
| 258 identifier.location, identifier.text); | |
| 259 // Do not lose EOF token. | |
| 260 ungetToken(token); | |
| 261 return false; | |
| 262 } | |
| 263 | |
| 264 bool isArg = false; // True if token is part of the current argument. | |
| 265 switch (token.type) | |
| 266 { | |
| 267 case '(': | |
| 268 ++openParens; | |
| 269 isArg = true; | |
| 270 break; | |
| 271 case ')': | |
| 272 --openParens; | |
| 273 isArg = openParens != 0; | |
| 274 break; | |
| 275 case ',': | |
| 276 // The individual arguments are separated by comma tokens, but | |
| 277 // the comma tokens between matching inner parentheses do not | |
| 278 // seperate arguments. | |
| 279 if (openParens == 1) args->push_back(MacroArg()); | |
| 280 isArg = openParens != 1; | |
| 281 break; | |
| 282 default: | |
| 283 isArg = true; | |
| 284 break; | |
| 285 } | |
| 286 if (isArg) | |
| 287 { | |
| 288 MacroArg& arg = args->back(); | |
| 289 // Initial whitespace is not part of the argument. | |
| 290 if (arg.empty()) token.setHasLeadingSpace(false); | |
| 291 arg.push_back(token); | |
| 292 } | |
| 293 } | |
| 294 | |
| 295 const Macro::Parameters& params = macro.parameters; | |
| 296 // If there is only one empty argument, it is equivalent to no argument. | |
| 297 if (params.empty() && (args->size() == 1) && args->front().empty()) | |
| 298 { | |
| 299 args->clear(); | |
| 300 } | |
| 301 // Validate the number of arguments. | |
| 302 if (args->size() != params.size()) | |
| 303 { | |
| 304 Diagnostics::ID id = args->size() < macro.parameters.size() ? | |
| 305 Diagnostics::MACRO_TOO_FEW_ARGS : | |
| 306 Diagnostics::MACRO_TOO_MANY_ARGS; | |
| 307 mDiagnostics->report(id, identifier.location, identifier.text); | |
| 308 return false; | |
| 309 } | |
| 310 | |
| 311 // Pre-expand each argument before substitution. | |
| 312 // This step expands each argument individually before they are | |
| 313 // inserted into the macro body. | |
| 314 for (std::size_t i = 0; i < args->size(); ++i) | |
| 315 { | |
| 316 MacroArg& arg = args->at(i); | |
| 317 TokenLexer lexer(&arg); | |
| 318 MacroExpander expander(&lexer, mMacroSet, mDiagnostics); | |
| 319 | |
| 320 arg.clear(); | |
| 321 expander.lex(&token); | |
| 322 while (token.type != Token::LAST) | |
| 323 { | |
| 324 arg.push_back(token); | |
| 325 expander.lex(&token); | |
| 326 } | |
| 327 } | |
| 328 return true; | |
| 329 } | |
| 330 | |
| 331 void MacroExpander::replaceMacroParams(const Macro& macro, | |
| 332 const std::vector<MacroArg>& args, | |
| 333 std::vector<Token>* replacements) | |
| 334 { | |
| 335 for (std::size_t i = 0; i < macro.replacements.size(); ++i) | |
| 336 { | |
| 337 const Token& repl = macro.replacements[i]; | |
| 338 if (repl.type != Token::IDENTIFIER) | |
| 339 { | |
| 340 replacements->push_back(repl); | |
| 341 continue; | |
| 342 } | |
| 343 | |
| 344 // TODO(alokp): Optimize this. | |
| 345 // There is no need to search for macro params every time. | |
| 346 // The param index can be cached with the replacement token. | |
| 347 Macro::Parameters::const_iterator iter = std::find( | |
| 348 macro.parameters.begin(), macro.parameters.end(), repl.text); | |
| 349 if (iter == macro.parameters.end()) | |
| 350 { | |
| 351 replacements->push_back(repl); | |
| 352 continue; | |
| 353 } | |
| 354 | |
| 355 std::size_t iArg = std::distance(macro.parameters.begin(), iter); | |
| 356 const MacroArg& arg = args[iArg]; | |
| 357 if (arg.empty()) | |
| 358 { | |
| 359 continue; | |
| 360 } | |
| 361 std::size_t iRepl = replacements->size(); | |
| 362 replacements->insert(replacements->end(), arg.begin(), arg.end()); | |
| 363 // The replacement token inherits padding properties from | |
| 364 // macro replacement token. | |
| 365 replacements->at(iRepl).setHasLeadingSpace(repl.hasLeadingSpace()); | |
| 366 } | |
| 367 } | |
| 368 | |
| 369 } // namespace pp | |
| 370 |
