return signalPassFailure();

  // Eliminate TPUCompilationResultOp now that the rewrite is complete.
  for (auto& it : compilation_results) {
    for (auto op : it.second) {
      if (!op.use_empty()) {
        mlir::InFlightDiagnostic err = op.emitError("uses remain post rewrite");
        for (auto user : op->getUsers())
          err.attachNote(user->getLoc()) << "remaining user";
        return signalPassFailure();

  }

  // Remove the read ops if they have no more uses.
  for (const auto& entry : var_access_info.per_resource_info) {
    const auto& info = entry.getSecond();
    if (info.read->use_empty()) info.read->erase();
  }
  return success();
}

// Checks if an ops parent is a tf_device.parallel_execute and the region the
// op is in is perfectly wrapped.

      then_name, else_name, if_region.getIsStateless());
  CopyAndOverrideAttributes(if_region, if_op, &builder);

  if_region.replaceAllUsesWith(if_op.getResults());
  if_region.erase();

  if (to_bool && to_bool.use_empty()) to_bool.erase();
  return success();
}

// Transform CaseRegion to Case.
LogicalResult RegionControlFlowToFunctional::ConvertCaseOp(
    SymbolTableCollection& symbol_table, CaseRegionOp case_region) {

    auto island_op = llvm::dyn_cast<IslandOp>(*iter);
    if (llvm::dyn_cast_or_null<TF::IdentityOp>(island_op.GetBody().front())) {
      if (island_op.getOutputs().use_empty()) {
        tpu_ops.erase(iter);
        return true;
      }
      std::vector<IslandOp> ops;
      if (incoming) {
        collect_output_users_islands(island_op, ops);
      } else {

    Value control_barrier = control_barrier_worklist.front();
    control_barrier_worklist.pop();

    // We can only erase control barriers whose uses have been erased as well.
    if (!control_barrier.use_empty()) continue;

    // Only values defined by IslandOp were inserted in the worklist.
    IslandOp current_island = cast<IslandOp>(control_barrier.getDefiningOp());

  LogicalResult matchAndRewrite(IslandOp op,
                                PatternRewriter &rewriter) const override {
    if (op.getNumOperands() != 0 || op.getNumResults() != 2 ||
        !op.getControl().use_empty() ||
        !HasSingleOpInBlock<YieldOp>(&op.GetBody()))
      return failure();

    rewriter.replaceOp(op, {op.GetYield().getOperand(0), nullptr});

    return success();
  }
};

    return;
  }

  auto value = values[0];
  auto replacement = replacements[0];
  auto tuple_type = mlir::dyn_cast<TupleType>(value.getType());
  if (!tuple_type) {
    if (!value.use_empty()) {
      auto new_element = builder.create<GetTupleElementOp>(replacement.getLoc(),
                                                           replacement, 0);
      value.replaceAllUsesWith(new_element.getResult());
    }

      op->getResult(0).replaceAllUsesWith(op->getOperand(0));

    // Leftover TPUReplicatedInput/TPUReplicatedOutput that are not of
    // `num_replicas` to 1.
    if (!op->use_empty()) {
      op->emitOpError() << "is expected to have no uses, but it is operand#"
                        << op->use_begin()->getOperandNumber() << " of "
                        << *op->use_begin()->getOwner();

  func.walk([&](quantfork::QuantizeCastOp q) {
    auto input_op = q.getArg().getDefiningOp();
    if (auto stats = dyn_cast_or_null<quantfork::StatisticsOp>(input_op)) {
      q.setOperand(stats.getArg());
      if (stats.use_empty()) stats.erase();
    }
  });

  // Step 1: forward pass: propagate any value scales which are not produces
  // by `SameOperandsAndResultsScale`. Additionally, remove the value scales

		si.AllocRange(PageBase(BaseChunkIdx, 0), PageBase(BaseChunkIdx+64, 0))
		si.NextGen()
		si.FreeRange(PageBase(BaseChunkIdx, 0), PageBase(BaseChunkIdx+64, 0))
		for ci := BaseChunkIdx; ci < BaseChunkIdx+64; ci++ {
			si.SetEmpty(ci)
		}
		si.ResetSearchAddrs()

		// Create and return test functions.
		mark = func(base, limit uintptr) {
			t.Helper()

			si.AllocRange(base, limit)
			si.FreeRange(base, limit)
		}