xref: /llvm-project/clang-tools-extra/clang-tidy/performance/NoexceptFunctionBaseCheck.cpp (revision 845618cf69e89313084a4e93f8ff31d8e6ea4499)

//===--- NoexceptFunctionCheck.cpp - clang-tidy ---------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "NoexceptFunctionBaseCheck.h"
#include "../utils/LexerUtils.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"

using namespace clang::ast_matchers;

namespace clang::tidy::performance {

void NoexceptFunctionBaseCheck::check(const MatchFinder::MatchResult &Result) {
  const auto *FuncDecl = Result.Nodes.getNodeAs<FunctionDecl>(BindFuncDeclName);
  assert(FuncDecl);

  if (SpecAnalyzer.analyze(FuncDecl) !=
      utils::ExceptionSpecAnalyzer::State::Throwing)
    return;

  // Don't complain about nothrow(false), but complain on nothrow(expr)
  // where expr evaluates to false.
  const auto *ProtoType = FuncDecl->getType()->castAs<FunctionProtoType>();
  const Expr *NoexceptExpr = ProtoType->getNoexceptExpr();
  if (NoexceptExpr) {
    NoexceptExpr = NoexceptExpr->IgnoreImplicit();
    if (!isa<CXXBoolLiteralExpr>(NoexceptExpr))
      reportNoexceptEvaluatedToFalse(FuncDecl, NoexceptExpr);
    return;
  }

  auto Diag = reportMissingNoexcept(FuncDecl);

  // Add FixIt hints.
  const SourceManager &SM = *Result.SourceManager;

  const SourceLocation NoexceptLoc =
      utils::lexer::getLocationForNoexceptSpecifier(FuncDecl, SM);
  if (NoexceptLoc.isValid())
    Diag << FixItHint::CreateInsertion(NoexceptLoc, " noexcept ");
}

} // namespace clang::tidy::performance