[clang][bytecode][NFC] Check InitializingBlocks in _within_lifetime (#155378)

This kind of check is exactly why InterpState::InitializingBlocks
exists.

Author: tbaederr

clang/lib/AST/ByteCode/InterpBuiltin.cpp

@@ -2505,12 +2505,8 @@ static bool interp__builtin_is_within_lifetime(InterpState &S, CodePtr OpPC,
   }
 
   // Check if we're currently running an initializer.
-  for (InterpFrame *Frame = S.Current; Frame; Frame = Frame->Caller) {
-    if (const Function *F = Frame->getFunction();
-        F && F->isConstructor() && Frame->getThis().block() == Ptr.block()) {
-      return Error(2);
-    }
-  }
+  if (llvm::is_contained(S.InitializingBlocks, Ptr.block()))
+    return Error(2);
   if (S.EvaluatingDecl && Ptr.getDeclDesc()->asVarDecl() == S.EvaluatingDecl)
     return Error(2);