message: [XLA:CPU] Annotate start indices in dynamic-{,update-}slice with the HLO name.
  This makes the IR a bit easier to follow.
diff: @@ -44,8 +44,11 @@ limitations under the License.
  namespace xla {
  +using llvm_ir::AsStringRef;
  using llvm_ir::IrArray;
  +using llvm_ir::IrName;
  using llvm_ir::SetToFirstInsertPoint;
  +using tensorflow::strings::StrCat;
  StatusOr<llvm::Value*> ElementalIrEmitter::EmitUnaryOp(
  const HloInstruction* op, llvm::Value* operand_value) const {
  @@ -721,9 +724,9 @@ llvm_ir::ElementGenerator ElementalIrEmitter::MakeRngElementGenerator(
  if (ir_builder_->GetInsertPoint() == in_block->end()) {
  body_block = llvm_ir::CreateBasicBlock(
  - nullptr, llvm_ir::IrName(hlo, "rng_body"), ir_builder_);
  + nullptr, IrName(hlo, "rng_body"), ir_builder_);
  out_block = llvm_ir::CreateBasicBlock(
  - nullptr, llvm_ir::IrName(hlo, "rng_out"), ir_builder_);
  + nullptr, IrName(hlo, "rng_out"), ir_builder_);
  llvm::BranchInst::Create(body_block, in_block);
  } else {
  body_block = in_block->splitBasicBlock(
  @@ -892,12 +895,10 @@ llvm_ir::ElementGenerator ElementalIrEmitter::MakeElementGenerator(
  ++operand_idx) {
  const HloInstruction* operand = hlo->operand(operand_idx);
  auto true_block = llvm_ir::CreateBasicBlock(
  - exit_block, tensorflow::strings::StrCat(
  - "concat_index_from_operand", operand_idx),
  + exit_block, StrCat("concat_index_from_operand", operand_idx),
  ir_builder_);
  auto false_block = llvm_ir::CreateBasicBlock(
  - exit_block, tensorflow::strings::StrCat(
  - "concat_index_not_from_operand", operand_idx),
  + exit_block, StrCat("concat_index_not_from_operand", operand_idx),
  ir_builder_);
  auto concat_dim_size =
  llvm::ConstantInt::get(source_index[concat_dim]->getType(),
  @@ -972,6 +973,8 @@ llvm_ir::ElementGenerator ElementalIrEmitter::MakeElementGenerator(
  TF_ASSIGN_OR_RETURN(
  llvm::Value * start_index_value,
  operand_to_generator.at(hlo->operand(1))(dim_index));
  + start_index_value->setName(
  + AsStringRef(IrName(hlo, StrCat("start_idx", i))));
  slice_start_index[i] = start_index_value;
  }
  @@ -1004,6 +1007,8 @@ llvm_ir::ElementGenerator ElementalIrEmitter::MakeElementGenerator(
  llvm_ir::IrArray::Index dim_index(1, ir_builder_->getInt64(i));
  TF_ASSIGN_OR_RETURN(llvm::Value * start_index_value,
  operand_to_generator.at(start_hlo)(dim_index));
  + start_index_value->setName(
  + AsStringRef(IrName(hlo, StrCat("start_idx", i))));
  slice_start_index[i] = ir_builder_->CreateZExtOrBitCast(
  start_index_value, index[i]->getType());
  // Emit IR to compute: slice_limit_index = start_index + update_dim
  @@ -1163,7 +1168,7 @@ llvm_ir::ElementGenerator ElementalIrEmitter::MakeElementGenerator(
  std::unique_ptr<llvm_ir::ForLoop> inner_loop =
  llvm_ir::ForLoop::EmitForLoop(
  - llvm_ir::IrName(hlo, "inner"), ir_builder_->getInt64(0),
  + IrName(hlo, "inner"), ir_builder_->getInt64(0),
  ir_builder_->getInt64(contracted_dim_size),
  ir_builder_->getInt64(1), ir_builder_);
  