[clang] [SYCL] SYCL host kernel launch support for the sycl_kernel_entry_point attribute. (PR #152403)

[Tom Honermann via cfe-commits]

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@@ -28,6 +28,9 @@
 // A unique kernel name type is required for each declared kernel entry point.
 template<int, int=0> struct KN;
 
+template<typename KernelName, typename... Ts>
+void sycl_kernel_launch(const char *, Ts... Args) {}
+
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tahonermann wrote:

With this PR, any call to a `sycl_kernel_entry_point` attributed function requires a `sycl_kernel_launch` declaration to be in scope (similar to how a CUDA kernel call requires a `cudaConfigureCall()` declaration to be in scope).

https://github.com/llvm/llvm-project/pull/152403