&while_op.getBody()};
  for (const auto& it : llvm::enumerate(regions)) {
    llvm::SetVector<Value> region_extern_values;
    getUsedValuesDefinedAbove(*it.value(), region_extern_values);

    // Sink down constants (including quantized constant) into the functions.
    for (auto extern_value : region_extern_values) {

llvm::SmallVector<Value, 4> CollectExternValues(mlir::RegionRange regions) {
  llvm::SetVector<Value> extern_values;

  for (Region* region : regions) {
    llvm::SetVector<Value> region_extern_values;
    getUsedValuesDefinedAbove(*region, region_extern_values);

    // Sink down constants into the functions.
    for (auto extern_value : region_extern_values) {
      if (!matchPattern(extern_value, m_Constant())) {