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

[Matt Arsenault 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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arsenm wrote:

This probably doesn't need the version check, if you do it's hiding another bug somewhere. I guess this can be a separate change since it's already doing it 

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