Add L-GPU and L-Kokkos as package extras (#515)

* Add L-GPU and L-Kokkos as package extras

* Auto update version

* Update changelog

* Temp enable the x86 wheel cache

* Return wheel storage functionality to normal

* Update readme

* Auto update version

* Trigger CI

* Update README.rst

Co-authored-by: Amintor Dusko <[email protected]>

---------

Co-authored-by: Dev version update bot <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Amintor Dusko <[email protected]>

Author: 3 people

.github/CHANGELOG.md

@@ -37,6 +37,9 @@
 
 ### Improvements
 
+* Add support for `pip install pennylane-lightning[kokkos]` for the OpenMP backend.
+  [(#515)](https://github.com/PennyLaneAI/pennylane-lightning/pull/515)
+
 * Update setup.py to allow for multi-package co-existence. The PennyLane_Lightning package now is the responsible for the core functionality, and will be depended upon by all other extensions.
   [(#504)] (https://github.com/PennyLaneAI/pennylane-lightning/pull/504)
 
@@ -62,6 +65,9 @@
 
 ### Bug fixes
 
+* Re-add support for `pip install pennylane-lightning[gpu]`.
+  [(#515)](https://github.com/PennyLaneAI/pennylane-lightning/pull/515)
+
 * Switch most L-Qubit default kernels to `LM`. Add `LM::multiQubitOp` tests, failing when targeting out-of-order wires clustered close to `num_qubits-1`. Fix the `LM::multiQubitOp` kernel implementation by introducing a generic `revWireParity` routine and replacing the `bitswap`-based implementation. Mimic the changes fixing the corresponding `multiQubitOp` and `expval` functors in L-Kokkos.
   [(#511)](https://github.com/PennyLaneAI/pennylane-lightning/pull/511)
 

README.rst

@@ -189,9 +189,27 @@ Note that OpenMP and BLAS are disabled in this setting.
 Lightning Kokkos installation
 =============================
 
+For linux systems, `lightning.kokkos` and be readily installed with an OpenMP backend by providing the optional ``[kokkos]`` tag: 
+
+.. code-block:: console
+
+    $ pip install pennylane-lightning[kokkos]
+
+This can be explicitly installed through PyPI as:
+
+.. code-block:: console
+
+    $ pip install pennylane-lightning-kokkos
+
+
+Building from source
+--------------------
+
+As Kokkos enables support for many different HPC-targetted hardware platforms, `lightning.kokkos` can be built to support any of these platforms when building from source.
+
 We suggest first installing Kokkos with the wanted configuration following the instructions found in the `Kokkos documentation <https://kokkos.github.io/kokkos-core-wiki/building.html>`_.
 Next, append the install location to ``CMAKE_PREFIX_PATH``.
-If an installation is not found, our builder will install it from scratch nevertheless.
+If an installation is not found, our builder will clone and install it during the build process.
 
 The simplest way to install PennyLane-Lightning-Kokkos (OpenMP backend) is using ``pip``.
 
@@ -220,7 +238,7 @@ To build the plugin directly with CMake:
    cmake -B build -DKokkos_ENABLE_OPENMP=ON -DPLKOKKOS_BUILD_TESTS=ON -DPL_BACKEND=lightning_kokkos -G Ninja
    cmake --build build
 
-Supported backend options are "SERIAL", "OPENMP", "THREADS", "HIP" and "CUDA" and the corresponding build options are ``-DKokkos_ENABLE_XXX=ON``, where ``XXX`` needs be replaced by the backend name, for instance ``OPENMP``.
+The supported backend options are "SERIAL", "OPENMP", "THREADS", "HIP" and "CUDA" and the corresponding build options are ``-DKokkos_ENABLE_XXX=ON``, where ``XXX`` needs be replaced by the backend name, for instance ``OPENMP``.
 One can activate simultaneously one serial, one parallel CPU host (e.g. "OPENMP", "THREADS") and one parallel GPU device backend (e.g. "HIP", "CUDA"), but not two of any category at the same time.
 For "HIP" and "CUDA", the appropriate software stacks are required to enable compilation and subsequent use.
 Similarly, the CMake option ``-DKokkos_ARCH_{...}=ON`` must also be specified to target a given architecture.

setup.py

@@ -207,6 +207,10 @@ def build_extension(self, ext: CMakeExtension):
     else [CMakeExtension(f"{backend}_ops")],
     "cmdclass": {"build_ext": CMakeBuild},
     "ext_package": "pennylane_lightning",
+    "extras_require": {
+        "gpu": ["pennylane-lightning-gpu"],
+        "kokkos": ["pennylane-lightning-kokkos"],
+    },
 }
 
 if backend == "lightning_qubit":