// them, and replace the fetch's input operands with the new yielded values.
//
// This allows our def-use based island coarsening algorithm to merge
// islands that independently feed into a fetch.
void InsertDummyIslandForFetch(FetchOp fetch) {
  llvm::SmallVector<Value, 4> data_fetches;
  llvm::SmallVector<Type, 4> data_types;
  llvm::SmallVector<Value, 4> control_fetches;
  data_fetches.reserve(fetch.getFetches().size());