[llvm] MCExpr-ify amd_kernel_code_t (PR #91587)

[Janek van Oirschot via llvm-commits]

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@@ -1229,7 +1229,13 @@ void initDefaultAMDKernelCodeT(AMDGPUMCKernelCodeT &KernelCode,
   KernelCode.amd_machine_version_minor = Version.Minor;
   KernelCode.amd_machine_version_stepping = Version.Stepping;
   KernelCode.kernel_code_entry_byte_offset = sizeof(amd_kernel_code_t);
-  KernelCode.wavefront_size = 6;
+  if (Version.Major >= 10 &&
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JanekvO wrote:

I should add that this is explicitly checked for in the parser: https://github.com/llvm/llvm-project/blob/82c5d350d200ccc5365d40eac187b9ec967af727/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp#L5905-L5908

https://github.com/llvm/llvm-project/pull/91587