clang-tools  16.0.0git
NoexceptMoveConstructorCheck.cpp
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1 //===--- NoexceptMoveConstructorCheck.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 #include "clang/Lex/Lexer.h"
13 #include "clang/Tooling/FixIt.h"
14 
15 using namespace clang::ast_matchers;
16 
17 namespace clang {
18 namespace tidy {
19 namespace performance {
20 
21 void NoexceptMoveConstructorCheck::registerMatchers(MatchFinder *Finder) {
22  Finder->addMatcher(
23  cxxMethodDecl(anyOf(cxxConstructorDecl(), hasOverloadedOperatorName("=")),
24  unless(isImplicit()), unless(isDeleted()))
25  .bind("decl"),
26  this);
27 }
28 
30  const MatchFinder::MatchResult &Result) {
31  if (const auto *Decl = Result.Nodes.getNodeAs<CXXMethodDecl>("decl")) {
32  bool IsConstructor = false;
33  if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(Decl)) {
34  if (!Ctor->isMoveConstructor())
35  return;
36  IsConstructor = true;
37  } else if (!Decl->isMoveAssignmentOperator()) {
38  return;
39  }
40 
41  const auto *ProtoType = Decl->getType()->castAs<FunctionProtoType>();
42 
43  if (isUnresolvedExceptionSpec(ProtoType->getExceptionSpecType()))
44  return;
45 
46  if (!isNoexceptExceptionSpec(ProtoType->getExceptionSpecType())) {
47  auto Diag = diag(Decl->getLocation(),
48  "move %select{assignment operator|constructor}0s should "
49  "be marked noexcept")
50  << IsConstructor;
51  // Add FixIt hints.
52  SourceManager &SM = *Result.SourceManager;
53  assert(Decl->getNumParams() > 0);
54  SourceLocation NoexceptLoc = Decl->getParamDecl(Decl->getNumParams() - 1)
55  ->getSourceRange()
56  .getEnd();
57  if (NoexceptLoc.isValid())
58  NoexceptLoc = Lexer::findLocationAfterToken(
59  NoexceptLoc, tok::r_paren, SM, Result.Context->getLangOpts(), true);
60  if (NoexceptLoc.isValid())
61  Diag << FixItHint::CreateInsertion(NoexceptLoc, " noexcept ");
62  return;
63  }
64 
65  // Don't complain about nothrow(false), but complain on nothrow(expr)
66  // where expr evaluates to false.
67  if (ProtoType->canThrow() == CT_Can) {
68  Expr *E = ProtoType->getNoexceptExpr();
69  E = E->IgnoreImplicit();
70  if (!isa<CXXBoolLiteralExpr>(E)) {
71  diag(E->getExprLoc(),
72  "noexcept specifier on the move %select{assignment "
73  "operator|constructor}0 evaluates to 'false'")
74  << IsConstructor;
75  }
76  }
77  }
78 }
79 
80 } // namespace performance
81 } // namespace tidy
82 } // namespace clang
E
const Expr * E
Definition: AvoidBindCheck.cpp:88
NoexceptMoveConstructorCheck.h
clang::ast_matchers
Definition: AbseilMatcher.h:14
Decl
const FunctionDecl * Decl
Definition: AvoidBindCheck.cpp:100
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
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clang::clangd::check
bool check(llvm::StringRef File, const ThreadsafeFS &TFS, const ClangdLSPServer::Options &Opts)
Definition: Check.cpp:415