[clang] [NFC][analyzer] Replace BlockInCriticalSection MutexDescriptor with C… (PR #224230)

[Balázs Benics via cfe-commits]

================
@@ -25,16 +25,52 @@
 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
 #include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
 
 #include <iterator>
 #include <utility>
-#include <variant>
 
 using namespace clang;
 using namespace ento;
 
+static const MemRegion *getFirstArgRegion(const CallEvent &Call) {
+  return Call.getArgSVal(0).getAsRegion();
+}
+
+static const MemRegion *getCXXThisRegion(const CallEvent &Call) {
+  return cast<CXXMemberCall>(Call).getCXXThisVal().getAsRegion();
+}
+
+static const MemRegion *getObjectUnderConstruction(const CallEvent &Call) {
+  if (std::optional<SVal> Object = Call.getReturnValueUnderConstruction())
+    return Object->getAsRegion();
+  return nullptr;
+}
+
+static const MemRegion *getCXXDestructorThisRegion(const CallEvent &Call) {
+  // An explicit destructor call (p->~T()) is a CXXMemberCall, not a
+  // CXXDestructorCall, so accept both.
+  if (const auto *Dtor = dyn_cast<CXXDestructorCall>(&Call))
+    return Dtor->getCXXThisVal().getAsRegion();
+  if (const auto *Member = dyn_cast<CXXMemberCall>(&Call);
+      Member && isa_and_nonnull<CXXDestructorDecl>(Member->getDecl()))
+    return Member->getCXXThisVal().getAsRegion();
+  return nullptr;
+}
+
+static bool isNotDeferLockUniqueLock(const CallEvent &Call) {
+  // Use the constructor's declared parameter type to identify the defer_lock_t
+  // overload.
+  ArrayRef<ParmVarDecl *> Params = Call.parameters();
+  if (Params.size() < 2)
+    return true;
+  QualType ParamType = Params[1]->getType().getNonReferenceType();
+  if (const auto *RD = ParamType->getAsRecordDecl();
+      RD && RD->getName() == "defer_lock_t" && RD->isInStdNamespace())
----------------
steakhal wrote:

Same sentiment here.
```suggestion
  const auto *RD = ParamType->getAsRecordDecl();
  if (RD && RD->getName() == "defer_lock_t" && RD->isInStdNamespace())
```

Actually, thinking about this a bit longer we should just have:
```c++
return !(<cond>);
```

https://github.com/llvm/llvm-project/pull/224230