Split env vars

Author: Alexander Batashev

sycl/doc/EnvironmentVariables.md

@@ -47,7 +47,6 @@ subject to change. Do not rely on these variables in production code.
 | `SYCL_CACHE_THRESHOLD` | Positive integer | Cache eviction threshold in days (default value is 7 for 1 week). Set to 0 for disabling time-based cache eviction. |
 | `SYCL_CACHE_MIN_DEVICE_IMAGE_SIZE` | Positive integer | Minimum size of device code image in bytes which is reasonable to cache on disk because disk access operation may take more time than do JIT compilation for it. Default value is 0 to cache all images. |
 | `SYCL_CACHE_MAX_DEVICE_IMAGE_SIZE` | Positive integer | Maximum size of device image in bytes which is cached. Too big kernels may overload disk too fast. Default value is 1 GB. |
-| `INTEL_ENABLE_OFFLOAD_ANNOTATIONS` | Any(\*) | Enables ITT Annotations support for SYCL runtime. This variable should only be used by tools, that support ITT Annotations. |
 
 `(*) Note: Any means this environment variable is effective when set to any non-null value.`
 

sycl/doc/InternalEnvironmentVariables.md

@@ -0,0 +1,12 @@
+# Internal Environment Variables
+
+**Warning:** the environment variables described in this document are used for
+development and debugging of DPC++ compiler and runtime. Their semantics are
+subject to change. Do not rely on these variables in production code.
+
+| Environment variable | Values | Description |
+| -------------------- | ------ | ----------- |
+| `INTEL_ENABLE_OFFLOAD_ANNOTATIONS` | Any(\*) | Enables ITT Annotations support for SYCL runtime. This variable should only be used by tools, that support ITT Annotations. |
+
+`(*) Note: Any means this environment variable is effective when set to any non-null value.`
+

sycl/doc/index.rst

@@ -28,6 +28,7 @@ Developing oneAPI DPC++ Compiler
    CompilerAndRuntimeDesign
    KernelParameterPassing
    EnvironmentVariables
+   InternalEnvironmentVariables
    PluginInterface
    ABIPolicyGuide
    SpecializationConstants