Adding config section

Author: chudur-budur

docs/source/user_guide/config.rst

@@ -0,0 +1,50 @@
+.. include:: ./../ext_links.txt
+
+Configuration Options for ``numba-dpex``
+========================================
+
+``numba-dpex`` provides a set of environment variables and flags for configuring different aspects of the compilation, debugging and execution of programs. The configuration flags of ``numba-dpex`` are mostly inherited from those of Numba*. They are defined in :file:`numba_dpex/core/config.py` and are listed as follows:
+
+``SAVE_IR_FILES``:
+    A flag to save the Numba* intermediate representation (IR) files generated by the compiler. Set to ``0`` by default.
+
+``SPIRV_VAL``:
+    A flag to turn Numba*'s ``SPIRV-VALIDATION`` switch. Set to ``0`` by default.
+
+``OFFLOAD_DIAGNOSTICS``:
+    A flag to dump the offload diagnostics. Set to ``0`` by default.
+
+``NATIVE_FP_ATOMICS``:
+    A flag to activate the native floating point (FP) atomcis support for supported devices. Requires ``llvm-spirv`` supporting the FP atomics extension. Set to ``0`` by default.
+
+``DEBUG``:
+    A flag to emit the debug info, inherited from `numba.core.config.DEBUG <https://github.com/numba/numba/blob/main/numba/core/config.py#L202>`__.
+
+``DEBUGINFO_DEFAULT``:
+    The default value for the `debug` flag. Inherited from `numba.core.config.DEBUGINFO_DEFAULT <https://github.com/numba/numba/blob/main/numba/core/config.py#L488>`__
+
+``DUMP_KERNEL_LLVM``:
+    A flag to emit LLVM assembly language format (``.ll``). Inherited from `numba.core.config.DUMP_OPTIMIZED <https://github.com/numba/numba/blob/main/numba/core/config.py#L301>`__
+
+``ENABLE_CACHE``:
+    A flag to enable caching, set ``NUMBA_DPEX_ENABLE_CACHE=0`` to turn off. Set to ``1`` by default.
+
+``CACHE_SIZE``:
+    A flag to specify the default cache size. Set to ``20`` by default.
+
+``DEBUG_CACHE``:
+    A flag to enable debugging of cahcing mechanism, set ``1`` to turn it on.
+
+``STATIC_LOCAL_MEM_PASS``:
+    A flag to turn on the ``ConstantSizeStaticLocalMemoryPass`` in the kernel pipeline. The pass is turned off by default.
+
+.. note::
+    In order to enable/disable each of the configuration flags, a ``NUMBA_DPEX``
+    prefix needs to be appended before each variable. For example, in order to
+    turn ``SAVE_IR_FILES`` flag on, it needs to be passed as ``NUMBA_DPEX_SAVE_IR_FILES=1``
+
+For example:
+
+.. code-block:: bash
+
+    user@host:~/NUMBA_DPEX_SAVE_IR_FILES=1 python numba_dpex_program.py

docs/source/user_guide/index.rst

@@ -17,4 +17,5 @@ User Guide
     dpnp_offload
     debugging/index
     caching
+    config
     useful_links