Commit 4de6b158 authored by Vladimir Plyashkun's avatar Vladimir Plyashkun Committed by Aaron Ballman
Browse files

Add an option to hicpp-signed-bitwise for positive integer literals. 

This gives developers a way to deviate from the coding standard to reduce the
chattiness of the check.
parent 0de262d7

clang-tools-extra/clang-tidy/hicpp/SignedBitwiseCheck.cpp

+16 −1
Original line number Diff line number Diff line
@@ -17,9 +17,24 @@ namespace clang { 
namespace tidy {

namespace hicpp {



SignedBitwiseCheck::SignedBitwiseCheck(StringRef Name,

                                       ClangTidyContext *Context)

    : ClangTidyCheck(Name, Context),

      IgnorePositiveIntegerLiterals(

          Options.get("IgnorePositiveIntegerLiterals", false)) {}



void SignedBitwiseCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {

  Options.store(Opts, "IgnorePositiveIntegerLiterals",

                IgnorePositiveIntegerLiterals);

}



void SignedBitwiseCheck::registerMatchers(MatchFinder *Finder) {

  const auto SignedIntegerOperand =

      expr(ignoringImpCasts(hasType(isSignedInteger()))).bind("signed-operand");

      (IgnorePositiveIntegerLiterals

           ? expr(ignoringImpCasts(hasType(isSignedInteger())),

                  unless(integerLiteral()))

           : expr(ignoringImpCasts(hasType(isSignedInteger()))))

          .bind("signed-operand");



  // The standard [bitmask.types] allows some integral types to be implemented

  // as signed types. Exclude these types from diagnosing for bitwise or(|) and

clang-tools-extra/clang-tidy/hicpp/SignedBitwiseCheck.h

+5 −2
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@@ -22,10 +22,13 @@ namespace hicpp { 
/// http://clang.llvm.org/extra/clang-tidy/checks/hicpp-signed-bitwise.html

class SignedBitwiseCheck : public ClangTidyCheck {

public:

  SignedBitwiseCheck(StringRef Name, ClangTidyContext *Context)

      : ClangTidyCheck(Name, Context) {}

  SignedBitwiseCheck(StringRef Name, ClangTidyContext *Context);

  void registerMatchers(ast_matchers::MatchFinder *Finder) override;

  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;

  void storeOptions(ClangTidyOptions::OptionMap &Options) override;



private:

  bool IgnorePositiveIntegerLiterals;

};



} // namespace hicpp

clang-tools-extra/docs/ReleaseNotes.rst

+5 −0
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@@ -103,6 +103,11 @@ Improvements to clang-tidy 
  Finds uses of deprecated Googletest APIs with names containing ``case`` and

  replaces them with equivalent APIs with ``suite``.



- Improved :doc:`hicpp-signed-bitwise

  <clang-tidy/checks/hicpp-signed-bitwise>` check.



  The check now supports the ``IgnorePositiveIntegerLiterals`` option.



- New :doc:`linuxkernel-must-use-errs

  <clang-tidy/checks/linuxkernel-must-use-errs>` check.

clang-tools-extra/docs/clang-tidy/checks/hicpp-signed-bitwise.rst

+8 −0
Original line number Diff line number Diff line
@@ -7,3 +7,11 @@ Finds uses of bitwise operations on signed integer types, which may lead to 
undefined or implementation defined behaviour.



The according rule is defined in the `High Integrity C++ Standard, Section 5.6.1 <http://www.codingstandard.com/section/5-6-shift-operators/>`_.



Options

-------



.. option:: IgnorePositiveIntegerLiterals



   If this option is set to `true`, the check will not warn on bitwise operations with positive integer literals, e.g. `~0`, `2 << 1`, etc.

   Default value is `false`.