Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 1 | //===--- LoopConvertCheck.cpp - clang-tidy---------------------------------===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | |
| 10 | #include "LoopConvertCheck.h" |
| 11 | #include "clang/AST/ASTContext.h" |
| 12 | #include "clang/ASTMatchers/ASTMatchFinder.h" |
| 13 | |
| 14 | using namespace clang; |
| 15 | using namespace clang::ast_matchers; |
| 16 | using namespace llvm; |
| 17 | |
| 18 | namespace clang { |
| 19 | namespace tidy { |
| 20 | namespace modernize { |
| 21 | |
| 22 | const char LoopNameArray[] = "forLoopArray"; |
| 23 | const char LoopNameIterator[] = "forLoopIterator"; |
| 24 | const char LoopNamePseudoArray[] = "forLoopPseudoArray"; |
| 25 | const char ConditionBoundName[] = "conditionBound"; |
| 26 | const char ConditionVarName[] = "conditionVar"; |
| 27 | const char IncrementVarName[] = "incrementVar"; |
| 28 | const char InitVarName[] = "initVar"; |
| 29 | const char BeginCallName[] = "beginCall"; |
| 30 | const char EndCallName[] = "endCall"; |
| 31 | const char ConditionEndVarName[] = "conditionEndVar"; |
| 32 | const char EndVarName[] = "endVar"; |
| 33 | const char DerefByValueResultName[] = "derefByValueResult"; |
| 34 | const char DerefByRefResultName[] = "derefByRefResult"; |
| 35 | |
| 36 | // shared matchers |
| 37 | static const TypeMatcher AnyType = anything(); |
| 38 | |
| 39 | static const StatementMatcher IntegerComparisonMatcher = |
| 40 | expr(ignoringParenImpCasts( |
| 41 | declRefExpr(to(varDecl(hasType(isInteger())).bind(ConditionVarName))))); |
| 42 | |
| 43 | static const DeclarationMatcher InitToZeroMatcher = |
| 44 | varDecl(hasInitializer(ignoringParenImpCasts(integerLiteral(equals(0))))) |
| 45 | .bind(InitVarName); |
| 46 | |
| 47 | static const StatementMatcher IncrementVarMatcher = |
| 48 | declRefExpr(to(varDecl(hasType(isInteger())).bind(IncrementVarName))); |
| 49 | |
| 50 | /// \brief The matcher for loops over arrays. |
| 51 | /// |
| 52 | /// In this general example, assuming 'j' and 'k' are of integral type: |
| 53 | /// \code |
| 54 | /// for (int i = 0; j < 3 + 2; ++k) { ... } |
| 55 | /// \endcode |
| 56 | /// The following string identifiers are bound to these parts of the AST: |
| 57 | /// ConditionVarName: 'j' (as a VarDecl) |
| 58 | /// ConditionBoundName: '3 + 2' (as an Expr) |
| 59 | /// InitVarName: 'i' (as a VarDecl) |
| 60 | /// IncrementVarName: 'k' (as a VarDecl) |
| 61 | /// LoopName: The entire for loop (as a ForStmt) |
| 62 | /// |
| 63 | /// Client code will need to make sure that: |
| 64 | /// - The three index variables identified by the matcher are the same |
| 65 | /// VarDecl. |
| 66 | /// - The index variable is only used as an array index. |
| 67 | /// - All arrays indexed by the loop are the same. |
| 68 | StatementMatcher makeArrayLoopMatcher() { |
| 69 | StatementMatcher ArrayBoundMatcher = |
| 70 | expr(hasType(isInteger())).bind(ConditionBoundName); |
| 71 | |
| 72 | return forStmt( |
Angel Garcia Gomez | 06d010c | 2015-08-25 15:44:00 +0000 | [diff] [blame] | 73 | unless(isInTemplateInstantiation()), |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 74 | hasLoopInit(declStmt(hasSingleDecl(InitToZeroMatcher))), |
| 75 | hasCondition(anyOf( |
| 76 | binaryOperator(hasOperatorName("<"), |
| 77 | hasLHS(IntegerComparisonMatcher), |
| 78 | hasRHS(ArrayBoundMatcher)), |
| 79 | binaryOperator(hasOperatorName(">"), hasLHS(ArrayBoundMatcher), |
| 80 | hasRHS(IntegerComparisonMatcher)))), |
| 81 | hasIncrement(unaryOperator(hasOperatorName("++"), |
| 82 | hasUnaryOperand(IncrementVarMatcher)))) |
| 83 | .bind(LoopNameArray); |
| 84 | } |
| 85 | |
| 86 | /// \brief The matcher used for iterator-based for loops. |
| 87 | /// |
| 88 | /// This matcher is more flexible than array-based loops. It will match |
| 89 | /// catch loops of the following textual forms (regardless of whether the |
| 90 | /// iterator type is actually a pointer type or a class type): |
| 91 | /// |
| 92 | /// Assuming f, g, and h are of type containerType::iterator, |
| 93 | /// \code |
| 94 | /// for (containerType::iterator it = container.begin(), |
| 95 | /// e = createIterator(); f != g; ++h) { ... } |
| 96 | /// for (containerType::iterator it = container.begin(); |
| 97 | /// f != anotherContainer.end(); ++h) { ... } |
| 98 | /// \endcode |
| 99 | /// The following string identifiers are bound to the parts of the AST: |
| 100 | /// InitVarName: 'it' (as a VarDecl) |
| 101 | /// ConditionVarName: 'f' (as a VarDecl) |
| 102 | /// LoopName: The entire for loop (as a ForStmt) |
| 103 | /// In the first example only: |
| 104 | /// EndVarName: 'e' (as a VarDecl) |
| 105 | /// ConditionEndVarName: 'g' (as a VarDecl) |
| 106 | /// In the second example only: |
| 107 | /// EndCallName: 'container.end()' (as a CXXMemberCallExpr) |
| 108 | /// |
| 109 | /// Client code will need to make sure that: |
| 110 | /// - The iterator variables 'it', 'f', and 'h' are the same. |
| 111 | /// - The two containers on which 'begin' and 'end' are called are the same. |
| 112 | /// - If the end iterator variable 'g' is defined, it is the same as 'f'. |
| 113 | StatementMatcher makeIteratorLoopMatcher() { |
| 114 | StatementMatcher BeginCallMatcher = |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 115 | cxxMemberCallExpr(argumentCountIs(0), |
| 116 | callee(cxxMethodDecl(hasName("begin")))) |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 117 | .bind(BeginCallName); |
| 118 | |
| 119 | DeclarationMatcher InitDeclMatcher = |
| 120 | varDecl(hasInitializer(anyOf(ignoringParenImpCasts(BeginCallMatcher), |
| 121 | materializeTemporaryExpr( |
| 122 | ignoringParenImpCasts(BeginCallMatcher)), |
| 123 | hasDescendant(BeginCallMatcher)))) |
| 124 | .bind(InitVarName); |
| 125 | |
| 126 | DeclarationMatcher EndDeclMatcher = |
| 127 | varDecl(hasInitializer(anything())).bind(EndVarName); |
| 128 | |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 129 | StatementMatcher EndCallMatcher = cxxMemberCallExpr( |
| 130 | argumentCountIs(0), callee(cxxMethodDecl(hasName("end")))); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 131 | |
| 132 | StatementMatcher IteratorBoundMatcher = |
| 133 | expr(anyOf(ignoringParenImpCasts( |
| 134 | declRefExpr(to(varDecl().bind(ConditionEndVarName)))), |
| 135 | ignoringParenImpCasts(expr(EndCallMatcher).bind(EndCallName)), |
| 136 | materializeTemporaryExpr(ignoringParenImpCasts( |
| 137 | expr(EndCallMatcher).bind(EndCallName))))); |
| 138 | |
| 139 | StatementMatcher IteratorComparisonMatcher = expr( |
| 140 | ignoringParenImpCasts(declRefExpr(to(varDecl().bind(ConditionVarName))))); |
| 141 | |
| 142 | StatementMatcher OverloadedNEQMatcher = |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 143 | cxxOperatorCallExpr(hasOverloadedOperatorName("!="), argumentCountIs(2), |
| 144 | hasArgument(0, IteratorComparisonMatcher), |
| 145 | hasArgument(1, IteratorBoundMatcher)); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 146 | |
| 147 | // This matcher tests that a declaration is a CXXRecordDecl that has an |
| 148 | // overloaded operator*(). If the operator*() returns by value instead of by |
| 149 | // reference then the return type is tagged with DerefByValueResultName. |
| 150 | internal::Matcher<VarDecl> TestDerefReturnsByValue = |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 151 | hasType(cxxRecordDecl(hasMethod(allOf( |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 152 | hasOverloadedOperatorName("*"), |
| 153 | anyOf( |
| 154 | // Tag the return type if it's by value. |
| 155 | returns(qualType(unless(hasCanonicalType(referenceType()))) |
| 156 | .bind(DerefByValueResultName)), |
| 157 | returns( |
| 158 | // Skip loops where the iterator's operator* returns an |
| 159 | // rvalue reference. This is just weird. |
| 160 | qualType(unless(hasCanonicalType(rValueReferenceType()))) |
| 161 | .bind(DerefByRefResultName))))))); |
| 162 | |
| 163 | return forStmt( |
Angel Garcia Gomez | 06d010c | 2015-08-25 15:44:00 +0000 | [diff] [blame] | 164 | unless(isInTemplateInstantiation()), |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 165 | hasLoopInit(anyOf(declStmt(declCountIs(2), |
| 166 | containsDeclaration(0, InitDeclMatcher), |
| 167 | containsDeclaration(1, EndDeclMatcher)), |
| 168 | declStmt(hasSingleDecl(InitDeclMatcher)))), |
| 169 | hasCondition( |
| 170 | anyOf(binaryOperator(hasOperatorName("!="), |
| 171 | hasLHS(IteratorComparisonMatcher), |
| 172 | hasRHS(IteratorBoundMatcher)), |
| 173 | binaryOperator(hasOperatorName("!="), |
| 174 | hasLHS(IteratorBoundMatcher), |
| 175 | hasRHS(IteratorComparisonMatcher)), |
| 176 | OverloadedNEQMatcher)), |
| 177 | hasIncrement(anyOf( |
| 178 | unaryOperator(hasOperatorName("++"), |
| 179 | hasUnaryOperand(declRefExpr( |
| 180 | to(varDecl(hasType(pointsTo(AnyType))) |
| 181 | .bind(IncrementVarName))))), |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 182 | cxxOperatorCallExpr( |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 183 | hasOverloadedOperatorName("++"), |
| 184 | hasArgument( |
| 185 | 0, declRefExpr(to(varDecl(TestDerefReturnsByValue) |
| 186 | .bind(IncrementVarName)))))))) |
| 187 | .bind(LoopNameIterator); |
| 188 | } |
| 189 | |
| 190 | /// \brief The matcher used for array-like containers (pseudoarrays). |
| 191 | /// |
| 192 | /// This matcher is more flexible than array-based loops. It will match |
| 193 | /// loops of the following textual forms (regardless of whether the |
| 194 | /// iterator type is actually a pointer type or a class type): |
| 195 | /// |
| 196 | /// Assuming f, g, and h are of type containerType::iterator, |
| 197 | /// \code |
| 198 | /// for (int i = 0, j = container.size(); f < g; ++h) { ... } |
| 199 | /// for (int i = 0; f < container.size(); ++h) { ... } |
| 200 | /// \endcode |
| 201 | /// The following string identifiers are bound to the parts of the AST: |
| 202 | /// InitVarName: 'i' (as a VarDecl) |
| 203 | /// ConditionVarName: 'f' (as a VarDecl) |
| 204 | /// LoopName: The entire for loop (as a ForStmt) |
| 205 | /// In the first example only: |
| 206 | /// EndVarName: 'j' (as a VarDecl) |
| 207 | /// ConditionEndVarName: 'g' (as a VarDecl) |
| 208 | /// In the second example only: |
| 209 | /// EndCallName: 'container.size()' (as a CXXMemberCallExpr) |
| 210 | /// |
| 211 | /// Client code will need to make sure that: |
| 212 | /// - The index variables 'i', 'f', and 'h' are the same. |
| 213 | /// - The containers on which 'size()' is called is the container indexed. |
| 214 | /// - The index variable is only used in overloaded operator[] or |
| 215 | /// container.at(). |
| 216 | /// - If the end iterator variable 'g' is defined, it is the same as 'j'. |
| 217 | /// - The container's iterators would not be invalidated during the loop. |
| 218 | StatementMatcher makePseudoArrayLoopMatcher() { |
| 219 | // Test that the incoming type has a record declaration that has methods |
| 220 | // called 'begin' and 'end'. If the incoming type is const, then make sure |
| 221 | // these methods are also marked const. |
| 222 | // |
| 223 | // FIXME: To be completely thorough this matcher should also ensure the |
| 224 | // return type of begin/end is an iterator that dereferences to the same as |
| 225 | // what operator[] or at() returns. Such a test isn't likely to fail except |
| 226 | // for pathological cases. |
| 227 | // |
| 228 | // FIXME: Also, a record doesn't necessarily need begin() and end(). Free |
| 229 | // functions called begin() and end() taking the container as an argument |
| 230 | // are also allowed. |
| 231 | TypeMatcher RecordWithBeginEnd = qualType( |
| 232 | anyOf(qualType(isConstQualified(), |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 233 | hasDeclaration(cxxRecordDecl( |
| 234 | hasMethod(cxxMethodDecl(hasName("begin"), isConst())), |
| 235 | hasMethod(cxxMethodDecl(hasName("end"), |
| 236 | isConst())))) // hasDeclaration |
| 237 | ), // qualType |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 238 | qualType(unless(isConstQualified()), |
| 239 | hasDeclaration( |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 240 | cxxRecordDecl(hasMethod(hasName("begin")), |
| 241 | hasMethod(hasName("end"))))) // qualType |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 242 | )); |
| 243 | |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 244 | StatementMatcher SizeCallMatcher = cxxMemberCallExpr( |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 245 | argumentCountIs(0), |
Aaron Ballman | b9ea09c | 2015-09-17 13:31:25 +0000 | [diff] [blame^] | 246 | callee(cxxMethodDecl(anyOf(hasName("size"), hasName("length")))), |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 247 | on(anyOf(hasType(pointsTo(RecordWithBeginEnd)), |
| 248 | hasType(RecordWithBeginEnd)))); |
| 249 | |
| 250 | StatementMatcher EndInitMatcher = |
| 251 | expr(anyOf(ignoringParenImpCasts(expr(SizeCallMatcher).bind(EndCallName)), |
| 252 | explicitCastExpr(hasSourceExpression(ignoringParenImpCasts( |
| 253 | expr(SizeCallMatcher).bind(EndCallName)))))); |
| 254 | |
| 255 | DeclarationMatcher EndDeclMatcher = |
| 256 | varDecl(hasInitializer(EndInitMatcher)).bind(EndVarName); |
| 257 | |
| 258 | StatementMatcher IndexBoundMatcher = |
| 259 | expr(anyOf(ignoringParenImpCasts(declRefExpr(to( |
| 260 | varDecl(hasType(isInteger())).bind(ConditionEndVarName)))), |
| 261 | EndInitMatcher)); |
| 262 | |
| 263 | return forStmt( |
Angel Garcia Gomez | 06d010c | 2015-08-25 15:44:00 +0000 | [diff] [blame] | 264 | unless(isInTemplateInstantiation()), |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 265 | hasLoopInit( |
| 266 | anyOf(declStmt(declCountIs(2), |
| 267 | containsDeclaration(0, InitToZeroMatcher), |
| 268 | containsDeclaration(1, EndDeclMatcher)), |
| 269 | declStmt(hasSingleDecl(InitToZeroMatcher)))), |
| 270 | hasCondition(anyOf( |
| 271 | binaryOperator(hasOperatorName("<"), |
| 272 | hasLHS(IntegerComparisonMatcher), |
| 273 | hasRHS(IndexBoundMatcher)), |
| 274 | binaryOperator(hasOperatorName(">"), hasLHS(IndexBoundMatcher), |
| 275 | hasRHS(IntegerComparisonMatcher)))), |
| 276 | hasIncrement(unaryOperator(hasOperatorName("++"), |
| 277 | hasUnaryOperand(IncrementVarMatcher)))) |
| 278 | .bind(LoopNamePseudoArray); |
| 279 | } |
| 280 | |
| 281 | /// \brief Determine whether Init appears to be an initializing an iterator. |
| 282 | /// |
| 283 | /// If it is, returns the object whose begin() or end() method is called, and |
| 284 | /// the output parameter isArrow is set to indicate whether the initialization |
| 285 | /// is called via . or ->. |
| 286 | static const Expr *getContainerFromBeginEndCall(const Expr *Init, bool IsBegin, |
| 287 | bool *IsArrow) { |
| 288 | // FIXME: Maybe allow declaration/initialization outside of the for loop. |
| 289 | const auto *TheCall = |
| 290 | dyn_cast_or_null<CXXMemberCallExpr>(digThroughConstructors(Init)); |
| 291 | if (!TheCall || TheCall->getNumArgs() != 0) |
| 292 | return nullptr; |
| 293 | |
| 294 | const auto *Member = dyn_cast<MemberExpr>(TheCall->getCallee()); |
| 295 | if (!Member) |
| 296 | return nullptr; |
| 297 | StringRef Name = Member->getMemberDecl()->getName(); |
| 298 | StringRef TargetName = IsBegin ? "begin" : "end"; |
| 299 | if (Name != TargetName) |
| 300 | return nullptr; |
| 301 | |
| 302 | const Expr *SourceExpr = Member->getBase(); |
| 303 | if (!SourceExpr) |
| 304 | return nullptr; |
| 305 | |
| 306 | *IsArrow = Member->isArrow(); |
| 307 | return SourceExpr; |
| 308 | } |
| 309 | |
| 310 | /// \brief Determines the container whose begin() and end() functions are called |
| 311 | /// for an iterator-based loop. |
| 312 | /// |
| 313 | /// BeginExpr must be a member call to a function named "begin()", and EndExpr |
| 314 | /// must be a member. |
| 315 | static const Expr *findContainer(ASTContext *Context, const Expr *BeginExpr, |
| 316 | const Expr *EndExpr, |
| 317 | bool *ContainerNeedsDereference) { |
| 318 | // Now that we know the loop variable and test expression, make sure they are |
| 319 | // valid. |
| 320 | bool BeginIsArrow = false; |
| 321 | bool EndIsArrow = false; |
| 322 | const Expr *BeginContainerExpr = |
| 323 | getContainerFromBeginEndCall(BeginExpr, /*IsBegin=*/true, &BeginIsArrow); |
| 324 | if (!BeginContainerExpr) |
| 325 | return nullptr; |
| 326 | |
| 327 | const Expr *EndContainerExpr = |
| 328 | getContainerFromBeginEndCall(EndExpr, /*IsBegin=*/false, &EndIsArrow); |
| 329 | // Disallow loops that try evil things like this (note the dot and arrow): |
| 330 | // for (IteratorType It = Obj.begin(), E = Obj->end(); It != E; ++It) { } |
| 331 | if (!EndContainerExpr || BeginIsArrow != EndIsArrow || |
| 332 | !areSameExpr(Context, EndContainerExpr, BeginContainerExpr)) |
| 333 | return nullptr; |
| 334 | |
| 335 | *ContainerNeedsDereference = BeginIsArrow; |
| 336 | return BeginContainerExpr; |
| 337 | } |
| 338 | |
| 339 | /// \brief Obtain the original source code text from a SourceRange. |
| 340 | static StringRef getStringFromRange(SourceManager &SourceMgr, |
| 341 | const LangOptions &LangOpts, |
| 342 | SourceRange Range) { |
| 343 | if (SourceMgr.getFileID(Range.getBegin()) != |
Alexander Kornienko | 74a44d9 | 2015-08-20 13:18:23 +0000 | [diff] [blame] | 344 | SourceMgr.getFileID(Range.getEnd())) { |
| 345 | return StringRef(); // Empty string. |
| 346 | } |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 347 | |
| 348 | return Lexer::getSourceText(CharSourceRange(Range, true), SourceMgr, |
| 349 | LangOpts); |
| 350 | } |
| 351 | |
| 352 | /// \brief If the given expression is actually a DeclRefExpr, find and return |
| 353 | /// the underlying VarDecl; otherwise, return NULL. |
| 354 | static const VarDecl *getReferencedVariable(const Expr *E) { |
| 355 | if (const DeclRefExpr *DRE = getDeclRef(E)) |
| 356 | return dyn_cast<VarDecl>(DRE->getDecl()); |
| 357 | return nullptr; |
| 358 | } |
| 359 | |
| 360 | /// \brief Returns true when the given expression is a member expression |
| 361 | /// whose base is `this` (implicitly or not). |
| 362 | static bool isDirectMemberExpr(const Expr *E) { |
| 363 | if (const auto *Member = dyn_cast<MemberExpr>(E->IgnoreParenImpCasts())) |
| 364 | return isa<CXXThisExpr>(Member->getBase()->IgnoreParenImpCasts()); |
| 365 | return false; |
| 366 | } |
| 367 | |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 368 | /// \brief Returns true when it can be guaranteed that the elements of the |
| 369 | /// container are not being modified. |
| 370 | static bool usagesAreConst(const UsageResult &Usages) { |
| 371 | // FIXME: Make this function more generic. |
| 372 | return Usages.empty(); |
| 373 | } |
| 374 | |
| 375 | /// \brief Returns true if the elements of the container are never accessed |
| 376 | /// by reference. |
| 377 | static bool usagesReturnRValues(const UsageResult &Usages) { |
| 378 | for (const auto &U : Usages) { |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 379 | if (U.Expression && !U.Expression->isRValue()) |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 380 | return false; |
| 381 | } |
| 382 | return true; |
| 383 | } |
| 384 | |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 385 | /// \brief Returns true if the container is const-qualified. |
| 386 | static bool containerIsConst(const Expr *ContainerExpr, bool Dereference) { |
| 387 | if (const auto *VDec = getReferencedVariable(ContainerExpr)) { |
| 388 | QualType CType = VDec->getType(); |
| 389 | if (Dereference) { |
| 390 | if (!CType->isPointerType()) |
| 391 | return false; |
| 392 | CType = CType->getPointeeType(); |
| 393 | } |
| 394 | return CType.isConstQualified(); |
| 395 | } |
| 396 | return false; |
| 397 | } |
| 398 | |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 399 | LoopConvertCheck::LoopConvertCheck(StringRef Name, ClangTidyContext *Context) |
| 400 | : ClangTidyCheck(Name, Context), TUInfo(new TUTrackingInfo), |
| 401 | MinConfidence(StringSwitch<Confidence::Level>( |
| 402 | Options.get("MinConfidence", "reasonable")) |
| 403 | .Case("safe", Confidence::CL_Safe) |
| 404 | .Case("risky", Confidence::CL_Risky) |
| 405 | .Default(Confidence::CL_Reasonable)) {} |
| 406 | |
| 407 | void LoopConvertCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) { |
| 408 | SmallVector<std::string, 3> Confs{"risky", "reasonable", "safe"}; |
| 409 | Options.store(Opts, "MinConfidence", Confs[static_cast<int>(MinConfidence)]); |
| 410 | } |
| 411 | |
| 412 | /// \brief Computes the changes needed to convert a given for loop, and |
| 413 | /// applies it. |
| 414 | void LoopConvertCheck::doConversion( |
| 415 | ASTContext *Context, const VarDecl *IndexVar, const VarDecl *MaybeContainer, |
| 416 | StringRef ContainerString, const UsageResult &Usages, |
| 417 | const DeclStmt *AliasDecl, bool AliasUseRequired, bool AliasFromForInit, |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 418 | const ForStmt *TheLoop, RangeDescriptor Descriptor) { |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 419 | // If there aren't any usages, converting the loop would generate an unused |
| 420 | // variable warning. |
| 421 | if (Usages.size() == 0) |
| 422 | return; |
| 423 | |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 424 | auto Diag = diag(TheLoop->getForLoc(), "use range-based for loop instead"); |
| 425 | |
| 426 | std::string VarName; |
| 427 | bool VarNameFromAlias = (Usages.size() == 1) && AliasDecl; |
| 428 | bool AliasVarIsRef = false; |
| 429 | |
| 430 | if (VarNameFromAlias) { |
| 431 | const auto *AliasVar = cast<VarDecl>(AliasDecl->getSingleDecl()); |
| 432 | VarName = AliasVar->getName().str(); |
| 433 | AliasVarIsRef = AliasVar->getType()->isReferenceType(); |
| 434 | |
| 435 | // We keep along the entire DeclStmt to keep the correct range here. |
| 436 | const SourceRange &ReplaceRange = AliasDecl->getSourceRange(); |
| 437 | |
| 438 | std::string ReplacementText; |
| 439 | if (AliasUseRequired) { |
| 440 | ReplacementText = VarName; |
| 441 | } else if (AliasFromForInit) { |
| 442 | // FIXME: Clang includes the location of the ';' but only for DeclStmt's |
| 443 | // in a for loop's init clause. Need to put this ';' back while removing |
| 444 | // the declaration of the alias variable. This is probably a bug. |
| 445 | ReplacementText = ";"; |
| 446 | } |
| 447 | |
| 448 | Diag << FixItHint::CreateReplacement( |
| 449 | CharSourceRange::getTokenRange(ReplaceRange), ReplacementText); |
| 450 | // No further replacements are made to the loop, since the iterator or index |
| 451 | // was used exactly once - in the initialization of AliasVar. |
| 452 | } else { |
| 453 | VariableNamer Namer(&TUInfo->getGeneratedDecls(), |
| 454 | &TUInfo->getParentFinder().getStmtToParentStmtMap(), |
| 455 | TheLoop, IndexVar, MaybeContainer, Context); |
| 456 | VarName = Namer.createIndexName(); |
| 457 | // First, replace all usages of the array subscript expression with our new |
| 458 | // variable. |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 459 | for (const auto &Usage : Usages) { |
| 460 | std::string ReplaceText; |
| 461 | if (Usage.Expression) { |
| 462 | // If this is an access to a member through the arrow operator, after |
| 463 | // the replacement it must be accessed through the '.' operator. |
| 464 | ReplaceText = Usage.Kind == Usage::UK_MemberThroughArrow ? VarName + "." |
| 465 | : VarName; |
| 466 | } else { |
| 467 | // The Usage expression is only null in case of lambda captures (which |
| 468 | // are VarDecl). If the index is captured by value, add '&' to capture |
| 469 | // by reference instead. |
| 470 | ReplaceText = |
| 471 | Usage.Kind == Usage::UK_CaptureByCopy ? "&" + VarName : VarName; |
| 472 | } |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 473 | TUInfo->getReplacedVars().insert(std::make_pair(TheLoop, IndexVar)); |
| 474 | Diag << FixItHint::CreateReplacement( |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 475 | CharSourceRange::getTokenRange(Usage.Range), ReplaceText); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 476 | } |
| 477 | } |
| 478 | |
| 479 | // Now, we need to construct the new range expression. |
| 480 | SourceRange ParenRange(TheLoop->getLParenLoc(), TheLoop->getRParenLoc()); |
| 481 | |
| 482 | QualType AutoRefType = Context->getAutoDeductType(); |
| 483 | |
| 484 | // If the new variable name is from the aliased variable, then the reference |
| 485 | // type for the new variable should only be used if the aliased variable was |
| 486 | // declared as a reference. |
| 487 | if (!VarNameFromAlias || AliasVarIsRef) { |
| 488 | // If an iterator's operator*() returns a 'T&' we can bind that to 'auto&'. |
| 489 | // If operator*() returns 'T' we can bind that to 'auto&&' which will deduce |
| 490 | // to 'T&&&'. |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 491 | if (Descriptor.DerefByValue) { |
| 492 | if (!Descriptor.IsTriviallyCopyable) |
| 493 | AutoRefType = Context->getRValueReferenceType(AutoRefType); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 494 | } else { |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 495 | if (Descriptor.DerefByConstRef) |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 496 | AutoRefType = Context->getConstType(AutoRefType); |
| 497 | AutoRefType = Context->getLValueReferenceType(AutoRefType); |
| 498 | } |
| 499 | } |
| 500 | |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 501 | StringRef MaybeDereference = Descriptor.ContainerNeedsDereference ? "*" : ""; |
Alexander Kornienko | e1292f8 | 2015-08-19 16:54:51 +0000 | [diff] [blame] | 502 | std::string TypeString = AutoRefType.getAsString(); |
| 503 | std::string Range = ("(" + TypeString + " " + VarName + " : " + |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 504 | MaybeDereference + ContainerString + ")") |
| 505 | .str(); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 506 | Diag << FixItHint::CreateReplacement( |
| 507 | CharSourceRange::getTokenRange(ParenRange), Range); |
| 508 | TUInfo->getGeneratedDecls().insert(make_pair(TheLoop, VarName)); |
| 509 | } |
| 510 | |
| 511 | /// \brief Determine if the change should be deferred or rejected, returning |
| 512 | /// text which refers to the container iterated over if the change should |
| 513 | /// proceed. |
| 514 | StringRef LoopConvertCheck::checkRejections(ASTContext *Context, |
| 515 | const Expr *ContainerExpr, |
| 516 | const ForStmt *TheLoop) { |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 517 | // If we already modified the range of this for loop, don't do any further |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 518 | // updates on this iteration. |
| 519 | if (TUInfo->getReplacedVars().count(TheLoop)) |
| 520 | return ""; |
| 521 | |
| 522 | Context->getTranslationUnitDecl(); |
| 523 | TUInfo->getParentFinder(); |
| 524 | TUInfo->getParentFinder().gatherAncestors(Context->getTranslationUnitDecl()); |
| 525 | // Ensure that we do not try to move an expression dependent on a local |
| 526 | // variable declared inside the loop outside of it. |
| 527 | DependencyFinderASTVisitor DependencyFinder( |
| 528 | &TUInfo->getParentFinder().getStmtToParentStmtMap(), |
| 529 | &TUInfo->getParentFinder().getDeclToParentStmtMap(), |
| 530 | &TUInfo->getReplacedVars(), TheLoop); |
| 531 | |
| 532 | // FIXME: Determine when the external dependency isn't an expression converted |
| 533 | // by another loop. |
| 534 | if (DependencyFinder.dependsOnInsideVariable(ContainerExpr)) |
| 535 | return ""; |
| 536 | |
| 537 | StringRef ContainerString; |
| 538 | if (isa<CXXThisExpr>(ContainerExpr->IgnoreParenImpCasts())) { |
| 539 | ContainerString = "this"; |
| 540 | } else { |
| 541 | ContainerString = |
| 542 | getStringFromRange(Context->getSourceManager(), Context->getLangOpts(), |
| 543 | ContainerExpr->getSourceRange()); |
| 544 | } |
| 545 | |
| 546 | return ContainerString; |
| 547 | } |
| 548 | |
| 549 | /// \brief Given a loop header that would be convertible, discover all usages |
| 550 | /// of the index variable and convert the loop if possible. |
| 551 | void LoopConvertCheck::findAndVerifyUsages( |
| 552 | ASTContext *Context, const VarDecl *LoopVar, const VarDecl *EndVar, |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 553 | const Expr *ContainerExpr, const Expr *BoundExpr, const ForStmt *TheLoop, |
| 554 | LoopFixerKind FixerKind, RangeDescriptor Descriptor) { |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 555 | ForLoopIndexUseVisitor Finder(Context, LoopVar, EndVar, ContainerExpr, |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 556 | BoundExpr, |
| 557 | Descriptor.ContainerNeedsDereference); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 558 | |
| 559 | if (ContainerExpr) { |
| 560 | ComponentFinderASTVisitor ComponentFinder; |
| 561 | ComponentFinder.findExprComponents(ContainerExpr->IgnoreParenImpCasts()); |
| 562 | Finder.addComponents(ComponentFinder.getComponents()); |
| 563 | } |
| 564 | |
| 565 | if (!Finder.findAndVerifyUsages(TheLoop->getBody())) |
| 566 | return; |
| 567 | |
| 568 | Confidence ConfidenceLevel(Finder.getConfidenceLevel()); |
| 569 | if (FixerKind == LFK_Array) { |
| 570 | // The array being indexed by IndexVar was discovered during traversal. |
| 571 | ContainerExpr = Finder.getContainerIndexed()->IgnoreParenImpCasts(); |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 572 | |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 573 | // Very few loops are over expressions that generate arrays rather than |
| 574 | // array variables. Consider loops over arrays that aren't just represented |
| 575 | // by a variable to be risky conversions. |
| 576 | if (!getReferencedVariable(ContainerExpr) && |
| 577 | !isDirectMemberExpr(ContainerExpr)) |
| 578 | ConfidenceLevel.lowerTo(Confidence::CL_Risky); |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 579 | |
| 580 | // Use 'const' if the array is const. |
| 581 | if (containerIsConst(ContainerExpr, Descriptor.ContainerNeedsDereference)) |
| 582 | Descriptor.DerefByConstRef = true; |
| 583 | |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 584 | } else if (FixerKind == LFK_PseudoArray) { |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 585 | if (!Descriptor.DerefByValue && !Descriptor.DerefByConstRef) { |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 586 | const UsageResult &Usages = Finder.getUsages(); |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 587 | if (usagesAreConst(Usages) || |
| 588 | containerIsConst(ContainerExpr, |
| 589 | Descriptor.ContainerNeedsDereference)) { |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 590 | Descriptor.DerefByConstRef = true; |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 591 | } else if (usagesReturnRValues(Usages)) { |
| 592 | // If the index usages (dereference, subscript, at) return RValues, |
| 593 | // then we should not use a non-const reference. |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 594 | Descriptor.DerefByValue = true; |
| 595 | // Try to find the type of the elements on the container from the |
| 596 | // usages. |
| 597 | for (const Usage &U : Usages) { |
| 598 | if (!U.Expression || U.Expression->getType().isNull()) |
| 599 | continue; |
| 600 | QualType Type = U.Expression->getType().getCanonicalType(); |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 601 | if (U.Kind == Usage::UK_MemberThroughArrow) { |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 602 | if (!Type->isPointerType()) |
| 603 | continue; |
| 604 | Type = Type->getPointeeType(); |
| 605 | } |
| 606 | Descriptor.IsTriviallyCopyable = |
| 607 | Type.isTriviallyCopyableType(*Context); |
| 608 | } |
Angel Garcia Gomez | 692cbb5 | 2015-09-01 15:05:15 +0000 | [diff] [blame] | 609 | } |
| 610 | } |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 611 | } |
| 612 | |
| 613 | StringRef ContainerString = checkRejections(Context, ContainerExpr, TheLoop); |
| 614 | |
| 615 | if (ContainerString.empty() || ConfidenceLevel.getLevel() < MinConfidence) |
| 616 | return; |
| 617 | |
| 618 | doConversion(Context, LoopVar, getReferencedVariable(ContainerExpr), |
| 619 | ContainerString, Finder.getUsages(), Finder.getAliasDecl(), |
| 620 | Finder.aliasUseRequired(), Finder.aliasFromForInit(), TheLoop, |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 621 | Descriptor); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 622 | } |
| 623 | |
| 624 | void LoopConvertCheck::registerMatchers(MatchFinder *Finder) { |
Aaron Ballman | 8b0583e | 2015-08-28 17:58:10 +0000 | [diff] [blame] | 625 | // Only register the matchers for C++. Because this checker is used for |
| 626 | // modernization, it is reasonable to run it on any C++ standard with the |
| 627 | // assumption the user is trying to modernize their codebase. |
| 628 | if (getLangOpts().CPlusPlus) { |
| 629 | Finder->addMatcher(makeArrayLoopMatcher(), this); |
| 630 | Finder->addMatcher(makeIteratorLoopMatcher(), this); |
| 631 | Finder->addMatcher(makePseudoArrayLoopMatcher(), this); |
| 632 | } |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 633 | } |
| 634 | |
| 635 | void LoopConvertCheck::check(const MatchFinder::MatchResult &Result) { |
| 636 | const BoundNodes &Nodes = Result.Nodes; |
| 637 | Confidence ConfidenceLevel(Confidence::CL_Safe); |
| 638 | ASTContext *Context = Result.Context; |
| 639 | |
| 640 | const ForStmt *TheLoop; |
| 641 | LoopFixerKind FixerKind; |
| 642 | |
| 643 | if ((TheLoop = Nodes.getStmtAs<ForStmt>(LoopNameArray))) { |
| 644 | FixerKind = LFK_Array; |
| 645 | } else if ((TheLoop = Nodes.getStmtAs<ForStmt>(LoopNameIterator))) { |
| 646 | FixerKind = LFK_Iterator; |
| 647 | } else { |
| 648 | TheLoop = Nodes.getStmtAs<ForStmt>(LoopNamePseudoArray); |
| 649 | assert(TheLoop && "Bad Callback. No for statement"); |
| 650 | FixerKind = LFK_PseudoArray; |
| 651 | } |
| 652 | |
| 653 | // Check that we have exactly one index variable and at most one end variable. |
| 654 | const auto *LoopVar = Nodes.getDeclAs<VarDecl>(IncrementVarName); |
| 655 | const auto *CondVar = Nodes.getDeclAs<VarDecl>(ConditionVarName); |
| 656 | const auto *InitVar = Nodes.getDeclAs<VarDecl>(InitVarName); |
| 657 | if (!areSameVariable(LoopVar, CondVar) || !areSameVariable(LoopVar, InitVar)) |
| 658 | return; |
| 659 | const auto *EndVar = Nodes.getDeclAs<VarDecl>(EndVarName); |
| 660 | const auto *ConditionEndVar = Nodes.getDeclAs<VarDecl>(ConditionEndVarName); |
| 661 | if (EndVar && !areSameVariable(EndVar, ConditionEndVar)) |
| 662 | return; |
| 663 | |
| 664 | // If the end comparison isn't a variable, we can try to work with the |
| 665 | // expression the loop variable is being tested against instead. |
| 666 | const auto *EndCall = Nodes.getStmtAs<CXXMemberCallExpr>(EndCallName); |
| 667 | const auto *BoundExpr = Nodes.getStmtAs<Expr>(ConditionBoundName); |
Angel Garcia Gomez | bb9ca54 | 2015-09-11 10:02:07 +0000 | [diff] [blame] | 668 | |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 669 | // If the loop calls end()/size() after each iteration, lower our confidence |
| 670 | // level. |
| 671 | if (FixerKind != LFK_Array && !EndVar) |
| 672 | ConfidenceLevel.lowerTo(Confidence::CL_Reasonable); |
| 673 | |
| 674 | const Expr *ContainerExpr = nullptr; |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 675 | RangeDescriptor Descriptor{false, false, false, false}; |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 676 | // FIXME: Try to put most of this logic inside a matcher. Currently, matchers |
| 677 | // don't allow the ight-recursive checks in digThroughConstructors. |
| 678 | if (FixerKind == LFK_Iterator) { |
| 679 | ContainerExpr = findContainer(Context, LoopVar->getInit(), |
| 680 | EndVar ? EndVar->getInit() : EndCall, |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 681 | &Descriptor.ContainerNeedsDereference); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 682 | |
| 683 | QualType InitVarType = InitVar->getType(); |
| 684 | QualType CanonicalInitVarType = InitVarType.getCanonicalType(); |
| 685 | |
| 686 | const auto *BeginCall = Nodes.getNodeAs<CXXMemberCallExpr>(BeginCallName); |
| 687 | assert(BeginCall && "Bad Callback. No begin call expression"); |
| 688 | QualType CanonicalBeginType = |
| 689 | BeginCall->getMethodDecl()->getReturnType().getCanonicalType(); |
| 690 | if (CanonicalBeginType->isPointerType() && |
| 691 | CanonicalInitVarType->isPointerType()) { |
| 692 | QualType BeginPointeeType = CanonicalBeginType->getPointeeType(); |
| 693 | QualType InitPointeeType = CanonicalInitVarType->getPointeeType(); |
| 694 | // If the initializer and the variable are both pointers check if the |
| 695 | // un-qualified pointee types match otherwise we don't use auto. |
| 696 | if (!Context->hasSameUnqualifiedType(InitPointeeType, BeginPointeeType)) |
| 697 | return; |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 698 | Descriptor.IsTriviallyCopyable = |
| 699 | BeginPointeeType.isTriviallyCopyableType(*Context); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 700 | } else { |
| 701 | // Check for qualified types to avoid conversions from non-const to const |
| 702 | // iterator types. |
| 703 | if (!Context->hasSameType(CanonicalInitVarType, CanonicalBeginType)) |
| 704 | return; |
| 705 | } |
| 706 | |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 707 | const auto *DerefByValueType = |
| 708 | Nodes.getNodeAs<QualType>(DerefByValueResultName); |
| 709 | Descriptor.DerefByValue = DerefByValueType; |
| 710 | if (!Descriptor.DerefByValue) { |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 711 | if (const auto *DerefType = |
| 712 | Nodes.getNodeAs<QualType>(DerefByRefResultName)) { |
| 713 | // A node will only be bound with DerefByRefResultName if we're dealing |
| 714 | // with a user-defined iterator type. Test the const qualification of |
| 715 | // the reference type. |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 716 | Descriptor.DerefByConstRef = (*DerefType) |
| 717 | ->getAs<ReferenceType>() |
| 718 | ->getPointeeType() |
| 719 | .isConstQualified(); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 720 | } else { |
| 721 | // By nature of the matcher this case is triggered only for built-in |
| 722 | // iterator types (i.e. pointers). |
| 723 | assert(isa<PointerType>(CanonicalInitVarType) && |
| 724 | "Non-class iterator type is not a pointer type"); |
| 725 | QualType InitPointeeType = CanonicalInitVarType->getPointeeType(); |
| 726 | QualType BeginPointeeType = CanonicalBeginType->getPointeeType(); |
| 727 | // If the initializer and variable have both the same type just use auto |
| 728 | // otherwise we test for const qualification of the pointed-at type. |
| 729 | if (!Context->hasSameType(InitPointeeType, BeginPointeeType)) |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 730 | Descriptor.DerefByConstRef = InitPointeeType.isConstQualified(); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 731 | } |
| 732 | } else { |
| 733 | // If the dereference operator returns by value then test for the |
| 734 | // canonical const qualification of the init variable type. |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 735 | Descriptor.DerefByConstRef = CanonicalInitVarType.isConstQualified(); |
| 736 | Descriptor.IsTriviallyCopyable = |
| 737 | DerefByValueType->isTriviallyCopyableType(*Context); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 738 | } |
| 739 | } else if (FixerKind == LFK_PseudoArray) { |
| 740 | if (!EndCall) |
| 741 | return; |
| 742 | ContainerExpr = EndCall->getImplicitObjectArgument(); |
| 743 | const auto *Member = dyn_cast<MemberExpr>(EndCall->getCallee()); |
| 744 | if (!Member) |
| 745 | return; |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 746 | Descriptor.ContainerNeedsDereference = Member->isArrow(); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 747 | } |
| 748 | |
| 749 | // We must know the container or an array length bound. |
| 750 | if (!ContainerExpr && !BoundExpr) |
| 751 | return; |
| 752 | |
| 753 | if (ConfidenceLevel.getLevel() < MinConfidence) |
| 754 | return; |
| 755 | |
| 756 | findAndVerifyUsages(Context, LoopVar, EndVar, ContainerExpr, BoundExpr, |
Angel Garcia Gomez | d930ef7 | 2015-09-08 09:01:21 +0000 | [diff] [blame] | 757 | TheLoop, FixerKind, Descriptor); |
Alexander Kornienko | 0497084 | 2015-08-19 09:11:46 +0000 | [diff] [blame] | 758 | } |
| 759 | |
| 760 | } // namespace modernize |
| 761 | } // namespace tidy |
| 762 | } // namespace clang |