clang-tools-extra/clang-tidy/performance/TriviallyDestructibleCheck.cpp

   1 //===--- TriviallyDestructibleCheck.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
   9 #include "TriviallyDestructibleCheck.h"
  10 #include "../utils/LexerUtils.h"
  11 #include "../utils/Matchers.h"
  12 #include "clang/AST/ASTContext.h"
  13 #include "clang/ASTMatchers/ASTMatchFinder.h"
  14
  15 using namespace clang::ast_matchers;
  16 using namespace clang::ast_matchers::internal;
  17 using namespace clang::tidy::matchers;
  18
  19 namespace clang::tidy::performance {
  20
  21 namespace {
  22
  23 AST_MATCHER(Decl, isFirstDecl) { return Node.isFirstDecl(); }
  24
  25 AST_MATCHER_P(CXXRecordDecl, hasBase, Matcher<QualType>, InnerMatcher) {
  26   for (const CXXBaseSpecifier &BaseSpec : Node.bases()) {
  27     QualType BaseType = BaseSpec.getType();
  28     if (InnerMatcher.matches(BaseType, Finder, Builder))
  29       return true;
  30   }
  31   return false;
  32 }
  33
  34 } // namespace
  35
  36 void TriviallyDestructibleCheck::registerMatchers(MatchFinder *Finder) {
  37   Finder->addMatcher(
  38       cxxDestructorDecl(
  39           isDefaulted(),
  40           unless(anyOf(isFirstDecl(), isVirtual(),
  41                        ofClass(cxxRecordDecl(
  42                            anyOf(hasBase(unless(isTriviallyDestructible())),
  43                                  has(fieldDecl(unless(
  44                                      hasType(isTriviallyDestructible()))))))))))
  45           .bind("decl"),
  46       this);
  47 }
  48
  49 void TriviallyDestructibleCheck::check(const MatchFinder::MatchResult &Result) {
  50   const auto *MatchedDecl = Result.Nodes.getNodeAs<CXXDestructorDecl>("decl");
  51
  52   // Get locations of both first and out-of-line declarations.
  53   SourceManager &SM = *Result.SourceManager;
  54   const auto *FirstDecl = cast<CXXMethodDecl>(MatchedDecl->getFirstDecl());
  55   const SourceLocation FirstDeclEnd = utils::lexer::findNextTerminator(
  56       FirstDecl->getEndLoc(), SM, getLangOpts());
  57   const CharSourceRange SecondDeclRange = CharSourceRange::getTokenRange(
  58       MatchedDecl->getBeginLoc(),
  59       utils::lexer::findNextTerminator(MatchedDecl->getEndLoc(), SM,
  60                                        getLangOpts()));
  61   if (FirstDeclEnd.isInvalid() || SecondDeclRange.isInvalid())
  62     return;
  63
  64   // Report diagnostic.
  65   diag(FirstDecl->getLocation(),
  66        "class %0 can be made trivially destructible by defaulting the "
  67        "destructor on its first declaration")
  68       << FirstDecl->getParent()
  69       << FixItHint::CreateInsertion(FirstDeclEnd, " = default")
  70       << FixItHint::CreateRemoval(SecondDeclRange);
  71   diag(MatchedDecl->getLocation(), "destructor definition is here",
  72        DiagnosticIDs::Note);
  73 }
  74
  75 } // namespace clang::tidy::performance