if (!interface) return false;
  return interface.onlyHasEffect<MemoryEffects::Read>();
}

// Get read only variable handles in `func`.
llvm::DenseSet<ResourceHandle> GetReadOnlyVariables(func::FuncOp func) {
  llvm::DenseMap<ResourceHandle, llvm::SmallVector<Operation *, 4>> resources;

  // Get all VarHandleOps in the function.
  func.walk([&](Operation *op) {
    if (llvm::isa<VarHandleOp>(op)) {