[clang-tidy] initial version of readability-convert-member-functions-to-static

Summary:
Finds non-static member functions that can be made ``static``.

I have run this check (repeatedly) over llvm-project. It made 1708 member functions
``static``. Out of those, I had to exclude 22 via ``NOLINT`` because their address
was taken and stored in a variable of pointer-to-member type (e.g. passed to
llvm::StringSwitch).
It also made 243 member functions ``const``. (This is currently very conservative
to have no false-positives and can hopefully be extended in the future.)

You can find the results here: https://github.com/mgehre/llvm-project/commits/static_const_eval

Reviewers: alexfh, aaron.ballman

Subscribers: mgorny, xazax.hun, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61749

llvm-svn: 366265

1 files changed, 3 insertions, 0 deletions

diff --git a/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp b/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
index 5b2aed4..5005ba3 100644
--- a/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
+++ b/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
@@ -13,6 +13,7 @@
 #include "BracesAroundStatementsCheck.h"
 #include "ConstReturnTypeCheck.h"
 #include "ContainerSizeEmptyCheck.h"
+#include "ConvertMemberFunctionsToStatic.h"
 #include "DeleteNullPointerCheck.h"
 #include "DeletedDefaultCheck.h"
 #include "ElseAfterReturnCheck.h"
@@ -57,6 +58,8 @@ public:
         "readability-const-return-type");
     CheckFactories.registerCheck<ContainerSizeEmptyCheck>(
         "readability-container-size-empty");
+    CheckFactories.registerCheck<ConvertMemberFunctionsToStatic>(
+        "readability-convert-member-functions-to-static");
     CheckFactories.registerCheck<DeleteNullPointerCheck>(
         "readability-delete-null-pointer");
     CheckFactories.registerCheck<DeletedDefaultCheck>(