[clang] [alpha.webkit.UncountedCallArgsChecker] Allow a variable declaration in a trivial function. (PR #82291)

[Ryosuke Niwa via cfe-commits]

https://github.com/rniwa created https://github.com/llvm/llvm-project/pull/82291

None

>From b0519e342b2e145827d6d9de490f32d1dd9c5fe6 Mon Sep 17 00:00:00 2001
From: Ryosuke Niwa <rniwa at webkit.org>
Date: Sat, 17 Feb 2024 18:12:16 -0800
Subject: [PATCH] [alpha.webkit.UncountedCallArgsChecker] Allow a variable
 declaration in a trivial function.

---
 .../Checkers/WebKit/PtrTypesSemantics.cpp         |  7 +++++--
 .../Checkers/WebKit/uncounted-obj-arg.cpp         | 15 +++++++++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp b/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp
index a7891d2da07c18..eaaf207c462624 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/PtrTypesSemantics.cpp
@@ -309,8 +309,11 @@ class TrivialFunctionAnalysisVisitor
         return true;
       if (isa<EnumConstantDecl>(decl))
         return true;
-      if (auto *VD = dyn_cast<VarDecl>(decl))
-        return VD->hasConstantInitialization() && VD->getEvaluatedValue();
+      if (auto *VD = dyn_cast<VarDecl>(decl)) {
+        if (VD->hasConstantInitialization() && VD->getEvaluatedValue())
+          return true;
+        return Visit(VD->getInit());
+      }
     }
     return false;
   }
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp b/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
index ac16a31293f3de..a0b0111d5c4bed 100644
--- a/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
@@ -199,6 +199,7 @@ class RefCounted {
   bool trivial23() const { return OptionSet<Flags>::fromRaw(v).contains(Flags::Flag1); }
   int trivial24() const { ASSERT(v); return v; }
   unsigned trivial25() const { return __c11_atomic_load((volatile _Atomic(unsigned) *)&v, __ATOMIC_RELAXED); }
+  bool trivial26() { bool hasValue = v; return !hasValue; }
 
   static RefCounted& singleton() {
     static RefCounted s_RefCounted;
@@ -262,6 +263,15 @@ class RefCounted {
     return __c11_atomic_load((volatile _Atomic(unsigned) *)another(), __ATOMIC_RELAXED);
   }
 
+  void nonTrivial11() {
+    Number num(0.3);
+  }
+
+  bool nonTrivial12() {
+    bool val = otherFunction();
+    return val;
+  }
+
   unsigned v { 0 };
   Number* number { nullptr };
   Enum enumValue { Enum::Value1 };
@@ -309,6 +319,7 @@ class UnrelatedClass {
     getFieldTrivial().trivial23(); // no-warning
     getFieldTrivial().trivial24(); // no-warning
     getFieldTrivial().trivial25(); // no-warning
+    getFieldTrivial().trivial26(); // no-warning
     RefCounted::singleton().trivial18(); // no-warning
     RefCounted::singleton().someFunction(); // no-warning
 
@@ -334,6 +345,10 @@ class UnrelatedClass {
     // expected-warning at -1{{Call argument for 'this' parameter is uncounted and unsafe}}
     getFieldTrivial().nonTrivial10();
     // expected-warning at -1{{Call argument for 'this' parameter is uncounted and unsafe}}
+    getFieldTrivial().nonTrivial11();
+    // expected-warning at -1{{Call argument for 'this' parameter is uncounted and unsafe}}
+    getFieldTrivial().nonTrivial12();
+    // expected-warning at -1{{Call argument for 'this' parameter is uncounted and unsafe}}
   }
 };