[clang] [SYCL] Basic code generation for SYCL kernel caller offload entry point functions. (PR #133030)

[Fraser Cormack via cfe-commits]

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@@ -229,6 +229,12 @@ class CodeGenTypes {
   const CGFunctionInfo &arrangeBuiltinFunctionCall(QualType resultType,
                                                    const CallArgList &args);
 
+  /// A SYCL device kernel function is a free standing function with
+  /// spir_kernel calling convention
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frasercrmck wrote:

IIUC, using NVVM metadata to identify kernels is now legacy/deprecated. I believe the NVPTX target now uses the `ptx_kernel` calling convention exclusively. See https://github.com/llvm/llvm-project/pull/119261 and https://github.com/llvm/llvm-project/pull/120806 for example.

https://github.com/llvm/llvm-project/pull/133030