[clang-tidy] openmp-use-default-none - a new check

Summary:
Finds OpenMP directives that are allowed to contain `default` clause,
but either don't specify it, or the clause is specified but with the kind
other than `none`, and suggests to use `default(none)` clause.

Using `default(none)` clause changes the default variable visibility from
being implicitly determined, and thus forces developer to be explicit about the
desired data scoping for each variable.

Reviewers: JonasToth, aaron.ballman, xazax.hun, hokein, gribozavr

Reviewed By: JonasToth, aaron.ballman

Subscribers: jdoerfert, openmp-commits, klimek, sbenza, arphaman, Eugene.Zelenko, ABataev, mgorny, rnkovacs, guansong, cfe-commits

Tags: #clang-tools-extra, #openmp, #clang

Differential Revision: https://reviews.llvm.org/D57113

llvm-svn: 356801

1 files changed, 36 insertions, 0 deletions

diff --git a/clang-tools-extra/clang-tidy/openmp/UseDefaultNoneCheck.h b/clang-tools-extra/clang-tidy/openmp/UseDefaultNoneCheck.h
new file mode 100644
index 0000000..c5ff882
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/openmp/UseDefaultNoneCheck.h
@@ -0,0 +1,36 @@
+//===--- UseDefaultNoneCheck.h - clang-tidy ---------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_OPENMP_USEDEFAULTNONECHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_OPENMP_USEDEFAULTNONECHECK_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace openmp {
+
+/// Finds OpenMP directives that are allowed to contain a ``default`` clause,
+/// but either don't specify it or the clause is specified but with the kind
+/// other than ``none``, and suggests to use the ``default(none)`` clause.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/openmp-use-default-none.html
+class UseDefaultNoneCheck : public ClangTidyCheck {
+public:
+  UseDefaultNoneCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace openmp
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_OPENMP_USEDEFAULTNONECHECK_H