| 1 | //===--- ProBoundsPointerArithmeticCheck.cpp - clang-tidy------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | |
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| 9 | #include "ProBoundsPointerArithmeticCheck.h" |
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| 10 | #include "clang/AST/ASTContext.h" |
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| 11 | #include "clang/ASTMatchers/ASTMatchFinder.h" |
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| 12 | |
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| 13 | using namespace clang::ast_matchers; |
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| 14 | |
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| 15 | namespace clang::tidy::cppcoreguidelines { |
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| 16 | |
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| 17 | void ProBoundsPointerArithmeticCheck::registerMatchers(MatchFinder *Finder) { |
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| 18 | const auto AllPointerTypes = |
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| 19 | anyOf(hasType(InnerMatcher: hasUnqualifiedDesugaredType(InnerMatcher: pointerType())), |
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| 20 | hasType(InnerMatcher: autoType( |
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| 21 | hasDeducedType(hasUnqualifiedDesugaredType(InnerMatcher: pointerType())))), |
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| 22 | hasType(InnerMatcher: decltypeType(hasUnderlyingType(pointerType())))); |
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| 23 | |
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| 24 | // Flag all operators +, -, +=, -= that result in a pointer |
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| 25 | Finder->addMatcher( |
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| 26 | NodeMatch: binaryOperator( |
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| 27 | hasAnyOperatorName("+" , "-" , "+=" , "-=" ), AllPointerTypes, |
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| 28 | unless(hasLHS(InnerMatcher: ignoringImpCasts(InnerMatcher: declRefExpr(to(InnerMatcher: isImplicit())))))) |
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| 29 | .bind(ID: "expr" ), |
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| 30 | Action: this); |
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| 31 | |
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| 32 | // Flag all operators ++, -- that result in a pointer |
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| 33 | Finder->addMatcher( |
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| 34 | NodeMatch: unaryOperator(hasAnyOperatorName("++" , "--" ), |
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| 35 | hasType(InnerMatcher: hasUnqualifiedDesugaredType(InnerMatcher: pointerType())), |
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| 36 | unless(hasUnaryOperand( |
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| 37 | InnerMatcher: ignoringImpCasts(InnerMatcher: declRefExpr(to(InnerMatcher: isImplicit())))))) |
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| 38 | .bind(ID: "expr" ), |
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| 39 | Action: this); |
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| 40 | |
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| 41 | // Array subscript on a pointer (not an array) is also pointer arithmetic |
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| 42 | Finder->addMatcher( |
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| 43 | NodeMatch: arraySubscriptExpr( |
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| 44 | hasBase(InnerMatcher: ignoringImpCasts( |
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| 45 | InnerMatcher: anyOf(AllPointerTypes, |
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| 46 | hasType(InnerMatcher: decayedType(hasDecayedType(InnerType: pointerType())))))), |
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| 47 | hasIndex(InnerMatcher: hasType(InnerMatcher: isInteger()))) |
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| 48 | .bind(ID: "expr" ), |
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| 49 | Action: this); |
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| 50 | } |
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| 51 | |
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| 52 | void ProBoundsPointerArithmeticCheck::check( |
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| 53 | const MatchFinder::MatchResult &Result) { |
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| 54 | const auto *MatchedExpr = Result.Nodes.getNodeAs<Expr>(ID: "expr" ); |
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| 55 | |
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| 56 | diag(Loc: MatchedExpr->getExprLoc(), Description: "do not use pointer arithmetic" ); |
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| 57 | } |
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| 58 | |
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| 59 | } // namespace clang::tidy::cppcoreguidelines |
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| 60 | |
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