[SYCL] Promote KHR extensions to supported status

[dyniols]

This PR removes __DPCPP_ENABLE_UNFINISHED_KHR_EXTENSIONS guard from KHR extensions
that are supported:

- khr_dynamic_addrspace_cast
- khr_static_addrspace_cast  
- khr_work_item_queries
- khr_group_interface
- khr_queue_empty

Guard sycl_khr_free_function_commands with __DPCPP_ENABLE_UNFINISHED_KHR_EXTENSIONS.

[Copilot]

Pull request overview

This PR promotes several SYCL KHR extensions from “unfinished” to supported status by removing the __DPCPP_ENABLE_UNFINISHED_KHR_EXTENSIONS gating, updating the generated feature-test macros accordingly, and adjusting end-to-end tests to no longer require the guard macro for these now-supported APIs.

Changes:

• Remove __DPCPP_ENABLE_UNFINISHED_KHR_EXTENSIONS guards from supported KHR APIs (address space casts, work item queries, group interface, queue empty query).
• Update feature_test.hpp.in so the promoted KHR feature-test macros are unconditionally defined, and move SYCL_KHR_FREE_FUNCTION_COMMANDS under the unfinished guard.
• Update e2e tests to stop defining __DPCPP_ENABLE_UNFINISHED_KHR_EXTENSIONS for the promoted extensions.

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
sycl/test-e2e/GroupInterface/work_group.cpp	Removes unfinished-extension guard macro from Group Interface e2e coverage.
sycl/test-e2e/GroupInterface/sub_group.cpp	Removes unfinished-extension guard macro from Group Interface e2e coverage.
sycl/test-e2e/GroupInterface/leader_of.cpp	Removes unfinished-extension guard macro from Group Interface-related e2e coverage.
sycl/test-e2e/Basic/work_item_queries/work_item_queries.cpp	Removes unfinished-extension guard macro from KHR work-item-queries e2e coverage.
sycl/test-e2e/Basic/out_of_order_queue_status_khr_empty.cpp	Removes unfinished-extension guard macro from queue::khr_empty() e2e coverage.
sycl/test-e2e/Basic/in_order_queue_status_khr_empty.cpp	Removes unfinished-extension guard macro from queue::khr_empty() e2e coverage.
sycl/test-e2e/AddressCast/khr_static_addrspace_cast.cpp	Removes unfinished-extension guard macro from KHR static addrspace cast e2e coverage.
sycl/test-e2e/AddressCast/khr_dynamic_addrspace_cast.cpp	Removes unfinished-extension guard macro from KHR dynamic addrspace cast e2e coverage.
sycl/source/feature_test.hpp.in	Promotes KHR feature-test macros to unconditional definitions; guards SYCL_KHR_FREE_FUNCTION_COMMANDS.
sycl/include/sycl/queue.hpp	Makes queue::khr_empty() declaration unconditional (supported).
sycl/include/sycl/khr/work_item_queries.hpp	Removes unfinished-extension gating so the KHR work-item-queries API is always available.
sycl/include/sycl/khr/static_addrspace_cast.hpp	Removes unfinished-extension gating so the KHR static addrspace cast API is always available.
sycl/include/sycl/khr/group_interface.hpp	Removes per-header SYCL_KHR_GROUP_INTERFACE define (macro now comes from feature-test header).
sycl/include/sycl/khr/dynamic_addrspace_cast.hpp	Removes unfinished-extension gating so the KHR dynamic addrspace cast API is always available.

[dyniols]

I think it's valid I will do it in separate PR.

[dyniols]

Regarding that issue with usage of deprecated query. I have opened separate PR.
#21751

[iclsrc]

Round 2 review of the KHR extension promotion changes. The header guards and test macro removals look correct. One important issue: SYCL_KHR_FREE_FUNCTION_COMMANDS is being demoted (moved into the unfinished guard), which is a breaking change that warrants explicit callout.

[iclsrc]

🟡 Important: SYCL_KHR_FREE_FUNCTION_COMMANDS is being demoted, not promoted

In the previous state of this file, SYCL_KHR_FREE_FUNCTION_COMMANDS 1 was defined unconditionally (alongside SYCL_KHR_QUEUE_EMPTY_QUERY and other stable macros). This PR moves it into the #ifdef __DPCPP_ENABLE_UNFINISHED_KHR_EXTENSIONS block, meaning it will no longer be defined by default.

This is a breaking change for any existing code that uses #ifdef SYCL_KHR_FREE_FUNCTION_COMMANDS or relies on the macro being present in a standard build. The PR title claims to only promote extensions; this is an intentional demotion that should be called out explicitly in the commit message and PR description so that users are aware of the regression.

[gmlueck]

Nice! Can you also update the list in README.md?

[dyniols]

Nice! Can you also update the list in README.md?

Yes will do :)