| //===--- IncorrectRoundingsCheck.h - clang-tidy -----------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_INCORRECTROUNDINGSCHECK_H_ |
| #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_INCORRECTROUNDINGSCHECK_H_ |
| |
| #include "../ClangTidy.h" |
| |
| namespace clang { |
| namespace tidy { |
| namespace bugprone { |
| |
| /// \brief Checks the usage of patterns known to produce incorrect rounding. |
| /// Programmers often use |
| /// (int)(double_expression + 0.5) |
| /// to round the double expression to an integer. The problem with this |
| /// 1. It is unnecessarily slow. |
| /// 2. It is incorrect. The number 0.499999975 (smallest representable float |
| /// number below 0.5) rounds to 1.0. Even worse behavior for negative |
| /// numbers where both -0.5f and -1.4f both round to 0.0. |
| class IncorrectRoundingsCheck : public ClangTidyCheck { |
| public: |
| IncorrectRoundingsCheck(StringRef Name, ClangTidyContext *Context) |
| : ClangTidyCheck(Name, Context) {} |
| void registerMatchers(ast_matchers::MatchFinder *Finder) override; |
| void check(const ast_matchers::MatchFinder::MatchResult &Result) override; |
| }; |
| |
| } // namespace bugprone |
| } // namespace tidy |
| } // namespace clang |
| |
| #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_INCORRECTROUNDINGSCHECK_H_ |