[llvm] [AMDGPU] Rework architected SGPRs implementation (PR #79001)

[Jay Foad via llvm-commits]

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@@ -143,6 +143,11 @@ struct AMDGPUFunctionArgInfo {
   ArgDescriptor WorkGroupInfo;
   ArgDescriptor PrivateSegmentWaveByteOffset;
 
+  // System TTMPs.
+  ArgDescriptor ArchitectedWorkGroupIDX;
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jayfoad wrote:

OK. I started again from scratch: #79120

https://github.com/llvm/llvm-project/pull/79001