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

   1 //===--- NoexceptFunctionCheck.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 "NoexceptFunctionBaseCheck.h"
  10 #include "../utils/LexerUtils.h"
  11 #include "clang/AST/ASTContext.h"
  12 #include "clang/AST/Decl.h"
  13 #include "clang/ASTMatchers/ASTMatchFinder.h"
  14
  15 using namespace clang::ast_matchers;
  16
  17 namespace clang::tidy::performance {
  18
  19 void NoexceptFunctionBaseCheck::check(const MatchFinder::MatchResult &Result) {
  20   const auto *FuncDecl = Result.Nodes.getNodeAs<FunctionDecl>(BindFuncDeclName);
  21   assert(FuncDecl);
  22
  23   if (SpecAnalyzer.analyze(FuncDecl) !=
  24       utils::ExceptionSpecAnalyzer::State::Throwing)
  25     return;
  26
  27   // Don't complain about nothrow(false), but complain on nothrow(expr)
  28   // where expr evaluates to false.
  29   const auto *ProtoType = FuncDecl->getType()->castAs<FunctionProtoType>();
  30   const Expr *NoexceptExpr = ProtoType->getNoexceptExpr();
  31   if (NoexceptExpr) {
  32     NoexceptExpr = NoexceptExpr->IgnoreImplicit();
  33     if (!isa<CXXBoolLiteralExpr>(NoexceptExpr))
  34       reportNoexceptEvaluatedToFalse(FuncDecl, NoexceptExpr);
  35     return;
  36   }
  37
  38   auto Diag = reportMissingNoexcept(FuncDecl);
  39
  40   // Add FixIt hints.
  41   const SourceManager &SM = *Result.SourceManager;
  42
  43   const SourceLocation NoexceptLoc =
  44       utils::lexer::getLocationForNoexceptSpecifier(FuncDecl, SM);
  45   if (NoexceptLoc.isValid())
  46     Diag << FixItHint::CreateInsertion(NoexceptLoc, " noexcept ");
  47 }
  48
  49 } // namespace clang::tidy::performance