[XLA] First step in adding Literal slice classes, to improve interface safety

and prepare for enabling more efficient interfacing from Tensor to Literal to
reduce host to device latency.

More specically:
* Introducing a new LiteralBase abstract base class that contains all immutable
methods of from the old Literal class.

* Introducing a subclass LiteralSlice to replace original LiteralView class.
LiteralSlice class is read-only and does not own Shape nor any buffer through
the Pieces. Change a number of callers to use LiteralSlice directly.

* Change Literal class to explicitly own the underlying Shape as well as owning
the underlying buffer via Piece.

* Conversion from Literal to LiteralSlice is now done via an implicit
conversion constructor instead of inheritance.

* Decouple ShapeTree from Literal classes.

* Use copy-and-swap for assignment constructors.

* Other minor cleanups.

PiperOrigin-RevId: 196016576

1 files changed, 1 insertions, 1 deletions

diff --git a/tensorflow/compiler/xla/service/generic_transfer_manager.h b/tensorflow/compiler/xla/service/generic_transfer_manager.h
index 0579099de4..3343eca851 100644
--- a/tensorflow/compiler/xla/service/generic_transfer_manager.h
+++ b/tensorflow/compiler/xla/service/generic_transfer_manager.h
@@ -49,7 +49,7 @@ class GenericTransferManager : public TransferManager {
                                  const ShapedBuffer& device_buffer) override;
 
   Status TransferLiteralToInfeed(se::StreamExecutor* executor,
-                                 const Literal& literal) override;
+                                 const LiteralSlice& literal) override;
   Status TransferLiteralFromOutfeed(se::StreamExecutor* executor,
                                     const Shape& literal_shape,
                                     Literal* literal) override;