[clang] [SYCL] The sycl_kernel_entry_point attribute. (PR #111389)

[Tom Honermann via cfe-commits]

tahonermann wrote:

This is the first in a series of PRs to provide core language support for SYCL-aware host and device compilation and support for SYCL library implementations. The following links present a preliminary set of changes for future PRs that depend on this one. Some of these need a little work yet (e.g., some of the diagnostics need a bit of tweaking), but will be submitted in order as dependencies are accepted.

- PR 1: [SYCL] The sycl_kernel_entry_point attribute. (this PR)
- PR 2: [\[SYCL\] Diagnostics for the sycl_kernel_entry_point attribute.](https://github.com/tahonermann/llvm-project/compare/sycl-upstream-fe-pr1...sycl-upstream-fe-pr2)
- PR 3: [\[SYCL\] AST support for SYCL kernel entry point functions.](https://github.com/tahonermann/llvm-project/compare/sycl-upstream-fe-pr2...sycl-upstream-fe-pr3)
- PR 4: [\[SYCL\] Offload kernel code generation for SYCL kernel entry point functions.](https://github.com/tahonermann/llvm-project/compare/sycl-upstream-fe-pr3...sycl-upstream-fe-pr4)
- ...
- PR X: [\[SYCL\] Remove the sycl_kernel attribute.](https://github.com/tahonermann/llvm-project/compare/sycl-upstream-fe-pr4...sycl-upstream-fe-rm-sycl_kernel-attr)

The last one listed above is to remove the existing `sycl_kernel` attribute pending further discussion. It is believed that there are no users of that attribute (other than Intel) and that it might be possible to remove it without a deprecation period. We'll follow up with an RFC for that at a later date.

https://github.com/llvm/llvm-project/pull/111389