Dynamic Selection Adding ResourceAdapter to support queue*

[danhoeflinger]

This PR allows users to provide a resource_adapter alongside a resource where the resulting base_resource = resource_adapter(resource) defines the default backend implementation.

This enables a use case where a user may want a resource to contain more or even a different variant as compared to the core base resource which defines a backend implementation.

The motivating use case is using sycl::queue* as the resource type alongside an adapter which dereferences. This allows less overhead copying pointers rather than full queues. It also allows the pointer to be used as a unique identifier to do things like look up a memory space in a global map.

Alternatively, you could envision a resource being provided which is a std::pair<sycl::queue, usm_pointer>, and an adapter functor std::get<0> to solve a similar use case (without the potential benefit of reducing overhead).

[Copilot]

Pull Request Overview

This PR introduces support for resource adapters in the dynamic selection framework, allowing users to provide a resource_adapter alongside a resource where the resulting base_resource = resource_adapter(resource) defines the default backend implementation. This enables use cases like using sycl::queue* as the resource type with a dereference adapter to reduce copying overhead and enable pointer-based lookup patterns.

Key Changes

• Adds ResourceAdapter template parameter to policy classes and backend implementations
• Updates test utilities to support passing adapter arguments to policy constructors
• Extends test coverage to include pointer-based resource scenarios with dereference adapters

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/support/test_dynamic_selection_utils.h	Updated test utility functions to accept variadic arguments for adapter support
test/support/test_dynamic_load_utils.h	Enhanced dynamic load test utilities with adapter support and templated initialization
test/parallel_api/dynamic_selection/sycl/test_round_robin_policy_sycl.pass.cpp	Added tests for both direct sycl::queue and sycl::queue* with dereference adapter
test/parallel_api/dynamic_selection/sycl/test_fixed_resource_policy_sycl.pass.cpp	Extended tests to cover pointer-based resources with adapters
test/parallel_api/dynamic_selection/sycl/test_dynamic_load_policy_sycl.pass.cpp	Added comprehensive testing for dynamic load policy with adapter support
include/oneapi/dpl/internal/dynamic_selection_impl/sycl_backend.h	Refactored to support ResourceAdapter template parameter and adapter-based resource handling
include/oneapi/dpl/internal/dynamic_selection_impl/round_robin_policy.h	Added ResourceAdapter template parameter with default std::identity
include/oneapi/dpl/internal/dynamic_selection_impl/policy_base.h	Updated initialization to support variadic arguments for adapter passing
include/oneapi/dpl/internal/dynamic_selection_impl/fixed_resource_policy.h	Enhanced with ResourceAdapter support and updated constructor signatures
include/oneapi/dpl/internal/dynamic_selection_impl/dynamic_load_policy.h	Added ResourceAdapter template parameter and updated policy instantiation
include/oneapi/dpl/internal/dynamic_selection_impl/default_backend.h	Restructured with default_backend_impl base class and ResourceAdapter support

Comments suppressed due to low confidence (1)

[egfefey]

Looks like std::identity is c++20, are we able to implement its functionality for use with c++17?

[danhoeflinger]

yeah, we have an alternative in oneDPL we can use.