clang-tools  12.0.0git
ProBoundsPointerArithmeticCheck.cpp
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1 //===--- ProBoundsPointerArithmeticCheck.cpp - clang-tidy------------------===//
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 
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 
13 using namespace clang::ast_matchers;
14 
15 namespace clang {
16 namespace tidy {
17 namespace cppcoreguidelines {
18 
19 void ProBoundsPointerArithmeticCheck::registerMatchers(MatchFinder *Finder) {
20  if (!getLangOpts().CPlusPlus)
21  return;
22 
23  const auto AllPointerTypes = anyOf(
24  hasType(pointerType()), hasType(autoType(hasDeducedType(pointerType()))),
25  hasType(decltypeType(hasUnderlyingType(pointerType()))));
26 
27  // Flag all operators +, -, +=, -=, ++, -- that result in a pointer
28  Finder->addMatcher(
29  binaryOperator(
30  hasAnyOperatorName("+", "-", "+=", "-="), AllPointerTypes,
31  unless(hasLHS(ignoringImpCasts(declRefExpr(to(isImplicit()))))))
32  .bind("expr"),
33  this);
34 
35  Finder->addMatcher(
36  unaryOperator(hasAnyOperatorName("++", "--"), hasType(pointerType()))
37  .bind("expr"),
38  this);
39 
40  // Array subscript on a pointer (not an array) is also pointer arithmetic
41  Finder->addMatcher(
42  arraySubscriptExpr(
43  hasBase(ignoringImpCasts(
44  anyOf(AllPointerTypes,
45  hasType(decayedType(hasDecayedType(pointerType())))))))
46  .bind("expr"),
47  this);
48 }
49 
50 void ProBoundsPointerArithmeticCheck::check(
51  const MatchFinder::MatchResult &Result) {
52  const auto *MatchedExpr = Result.Nodes.getNodeAs<Expr>("expr");
53 
54  diag(MatchedExpr->getExprLoc(), "do not use pointer arithmetic");
55 }
56 
57 } // namespace cppcoreguidelines
58 } // namespace tidy
59 } // namespace clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//