[clang] Add the support for calling Ref::ptr accessor. (PR #80919)

[Ryosuke Niwa via cfe-commits]

https://github.com/rniwa updated https://github.com/llvm/llvm-project/pull/80919

>From 6476d4cbca68815a96cea56519e3f5c75b4f9738 Mon Sep 17 00:00:00 2001
From: Ryosuke Niwa <rniwa at webkit.org>
Date: Tue, 6 Feb 2024 17:56:01 -0800
Subject: [PATCH] [alpha.webkit.UncountedCallArgsChecker] Add the support for
 calling Ref::ptr accessor.

This accessor returns a pointer from Ref type and is therefore safe.
---
 .../Checkers/WebKit/PtrTypesSemantics.cpp            |  1 +
 clang/test/Analysis/Checkers/WebKit/mock-types.h     | 10 ++++++----
 .../Analysis/Checkers/WebKit/ref-ptr-accessor.cpp    | 12 ++++++++++++
 3 files changed, 19 insertions(+), 4 deletions(-)
 create mode 100644 clang/test/Analysis/Checkers/WebKit/ref-ptr-accessor.cpp

diff --git a/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp b/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp
index c1f180f31338cb..4bc3f7a8c9c3ce 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp
@@ -148,6 +148,7 @@ std::optional<bool> isGetterOfRefCounted(const CXXMethodDecl* M)
 
     if (((className == "Ref" || className == "RefPtr") &&
          methodName == "get") ||
+        (className == "Ref" && methodName == "ptr") ||
         ((className == "String" || className == "AtomString" ||
           className == "AtomStringImpl" || className == "UniqueString" ||
           className == "UniqueStringImpl" || className == "Identifier") &&
diff --git a/clang/test/Analysis/Checkers/WebKit/mock-types.h b/clang/test/Analysis/Checkers/WebKit/mock-types.h
index 5f570b8bee8cb8..f10d530e1109ef 100644
--- a/clang/test/Analysis/Checkers/WebKit/mock-types.h
+++ b/clang/test/Analysis/Checkers/WebKit/mock-types.h
@@ -2,13 +2,14 @@
 #define mock_types_1103988513531
 
 template <typename T> struct Ref {
-  T t;
+  T *t;
 
   Ref() : t{} {};
   Ref(T *) {}
-  T *get() { return nullptr; }
-  operator const T &() const { return t; }
-  operator T &() { return t; }
+  T *get() { return t; }
+  T *ptr() { return t; }
+  operator const T &() const { return *t; }
+  operator T &() { return *t; }
 };
 
 template <typename T> struct RefPtr {
@@ -39,6 +40,7 @@ template <typename T> bool operator!=(const RefPtr<T> &, T *) { return false; }
 template <typename T> bool operator!=(const RefPtr<T> &, T &) { return false; }
 
 struct RefCountable {
+  static Ref<RefCountable> create();
   void ref() {}
   void deref() {}
 };
diff --git a/clang/test/Analysis/Checkers/WebKit/ref-ptr-accessor.cpp b/clang/test/Analysis/Checkers/WebKit/ref-ptr-accessor.cpp
new file mode 100644
index 00000000000000..560dcfd4bdb094
--- /dev/null
+++ b/clang/test/Analysis/Checkers/WebKit/ref-ptr-accessor.cpp
@@ -0,0 +1,12 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=alpha.webkit.UncountedCallArgsChecker -verify %s
+// expected-no-diagnostics
+
+#include "mock-types.h"
+
+void someFunction(RefCountable*);
+
+void testFunction()
+{
+    Ref item = RefCountable::create();
+    someFunction(item.ptr());
+}