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

[Jay Foad via llvm-commits]

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@@ -107,8 +107,8 @@ SIMachineFunctionInfo::SIMachineFunctionInfo(const Function &F,
       MayNeedAGPRs = false; // We will select all MAI with VGPR operands.
   }
 
-  if (!AMDGPU::isGraphics(CC) ||
-      (CC == CallingConv::AMDGPU_CS && ST.hasArchitectedSGPRs())) {
+  if (!AMDGPU::isGraphics(CC) || CC == CallingConv::AMDGPU_CS ||
+      ST.hasArchitectedSGPRs()) {
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jayfoad wrote:

But I need `WorkGroupIDZ` to be set correctly when architected SGPRs are enabled. It is used below, line 177.

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