[alpha.webkit.UncountedCallArgsChecker] Check CXXOperatorCallExpr's this argument (llvm#198688)

This PR fixes the bug that we were not checking "this" parameter of
CXXOperatorCallExpr.

Author: rniwa

clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefCallArgsChecker.cpp

@@ -120,6 +120,14 @@ class RawPtrRefCallArgsChecker
       if (auto *MemberCallExpr = dyn_cast<CXXMemberCallExpr>(CE))
         checkThisArg(MemberCallExpr, D);
 
+      if (ArgIdx) {
+        auto *Arg = CE->getArg(0);
+        QualType ArgType = Arg->getType().getCanonicalType();
+        std::optional<bool> IsUnsafe = isUnsafeType(ArgType);
+        if (IsUnsafe && *IsUnsafe && !isPtrOriginSafe(Arg))
+          reportBugOnThis(Arg, D);
+      }
+
       for (auto P = F->param_begin();
            P < F->param_end() && ArgIdx < CE->getNumArgs(); ++P, ++ArgIdx) {
         // TODO: attributes.

clang/test/Analysis/Checkers/WebKit/call-args.cpp

@@ -330,18 +330,30 @@ namespace cxx_member_operator_call {
     Foo& operator+(RefCountable* bad);
     friend Foo& operator-(Foo& lhs, RefCountable* bad);
     void operator()(RefCountable* bad);
+    int operator[](unsigned i);
   };
 
   RefCountable* global;
 
-  void foo() {
+  struct Container : public RefCountable {
+    int m[4];
+    int& operator[](unsigned i) {
+      some_function();
+      return m[i];
+    }
+  };
+  Container container();
+
+  void foo12() {
     Foo f;
     f + global;
     // expected-warning@-1{{Call argument for parameter 'bad' is uncounted and unsafe}}
     f - global;
     // expected-warning@-1{{Call argument for parameter 'bad' is uncounted and unsafe}}
     f(global);
     // expected-warning@-1{{Call argument for parameter 'bad' is uncounted and unsafe}}
+    container()[0] = 3;
+    // expected-warning@-1{{Call argument for 'this' parameter is uncounted and unsafe}}
   }
 }
 

clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp

@@ -480,14 +480,14 @@ class RefCounted {
 
   int nonTrivial13() { return ~otherFunction(); }
   int nonTrivial14() { int r = 0xff; r |= otherFunction(); return r; }
-  void nonTrivial15() { ++complex; }
-  void nonTrivial16() { complex++; }
+  void nonTrivial15() { ++complex; } // expected-warning{{Call argument for 'this' parameter is uncounted and unsafe}}
+  void nonTrivial16() { complex++; } // expected-warning{{Call argument for 'this' parameter is uncounted and unsafe}}
   ComplexNumber nonTrivial17() {
-    return complex << 2;
+    return complex << 2; // expected-warning{{Call argument for 'this' parameter is uncounted and unsafe}}
     // expected-warning@-1{{Call argument is uncounted and unsafe}}
   }
   ComplexNumber nonTrivial18() {
-    return +complex;
+    return +complex; // expected-warning{{Call argument for 'this' parameter is uncounted and unsafe}}
     // expected-warning@-1{{Call argument is uncounted and unsafe}}
   }
   ComplexNumber* nonTrivial19() {