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

[Matt Arsenault via llvm-commits]

================
@@ -1218,39 +1219,36 @@ unsigned getAllocatedNumVGPRBlocks(const MCSubtargetInfo *STI,
 }
 } // end namespace IsaInfo
 
-void initDefaultAMDKernelCodeT(amd_kernel_code_t &Header,
+void initDefaultAMDKernelCodeT(AMDGPUMCKernelCodeT &KernelCode,
                                const MCSubtargetInfo *STI) {
   IsaVersion Version = getIsaVersion(STI->getCPU());
-
-  memset(&Header, 0, sizeof(Header));
-
-  Header.amd_kernel_code_version_major = 1;
-  Header.amd_kernel_code_version_minor = 2;
-  Header.amd_machine_kind = 1; // AMD_MACHINE_KIND_AMDGPU
-  Header.amd_machine_version_major = Version.Major;
-  Header.amd_machine_version_minor = Version.Minor;
-  Header.amd_machine_version_stepping = Version.Stepping;
-  Header.kernel_code_entry_byte_offset = sizeof(Header);
-  Header.wavefront_size = 6;
+  KernelCode.amd_kernel_code_version_major = 1;
+  KernelCode.amd_kernel_code_version_minor = 2;
+  KernelCode.amd_machine_kind = 1; // AMD_MACHINE_KIND_AMDGPU
+  KernelCode.amd_machine_version_major = Version.Major;
+  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 the code object does not support indirect functions, then the value must
   // be 0xffffffff.
-  Header.call_convention = -1;
+  KernelCode.call_convention = -1;
 
   // These alignment values are specified in powers of two, so alignment =
   // 2^n.  The minimum alignment is 2^4 = 16.
-  Header.kernarg_segment_alignment = 4;
-  Header.group_segment_alignment = 4;
-  Header.private_segment_alignment = 4;
+  KernelCode.kernarg_segment_alignment = 4;
+  KernelCode.group_segment_alignment = 4;
+  KernelCode.private_segment_alignment = 4;
 
   if (Version.Major >= 10) {
     if (STI->getFeatureBits().test(FeatureWavefrontSize32)) {
-      Header.wavefront_size = 5;
-      Header.code_properties |= AMD_CODE_PROPERTY_ENABLE_WAVEFRONT_SIZE32;
+      KernelCode.wavefront_size = 5;
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arsenm wrote:

this can just move up to the first write of wavefront_size 

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